By H. Topork. University of the Pacific.
As with particles and flters buy macrobid 100mg without prescription, deposition and retention of droplets within the airways is a minimum for droplets 2 purchase macrobid 100mg on-line. The mass In this device generic macrobid 100mg otc, a plate containing a piezo-electric crystal of the droplets is also important discount macrobid 100mg otc. The mass of the droplet vibrates at an ultrasonic frequency, typically around is proportional to r3, where r is the radius. Water is either dropped onto the plate, or the plate 10 times the radius will carry 1000 times the mass, or is placed in the water. However, droplets of this size carry only a very to deliver them to the patient (Fig. Note that maximum deposition occurs in the alveoli for particles with an aerodynamic diameter of approximately 0. Depo- ensure that the temperature of the delivered gas is that sition in the alveoli will be greater during oral breathing required by the user. The temperature of the gas in the and particularly when the upper airways are bypassed. If the temperature sensors are not sited correctly Problems with flters, humidifers in the middle of the gas fow the temperature of the delivered gas may be much greater than that indicated on and nebulizers the humidifer and required by the user and injury may When added at the Y-piece of a breathing system, flters result. A heater wire can be used to of one-ffth of the tidal volume to the dead space, so that reduce the condensation. Also, if the dead space is reduced, by With nebulizers, it is relatively easy to add a large using a smaller device, the resistance to gas fow increases, amount of moisture to the delivered gas, leading to exces- and the fltration effciency and moisture output decreases. Some nebulized drugs ifying the inspired gas, this method produced droplets of can block some types of flter. This increased the risk medication will also be lost into the expiratory limb of of infection to a patient. This proportion heated humidifers is low, as the gas passes over, rather depends on the inspiratory : expiratory ratio of the breath- than through, the water. Eur J Anaesthesiol for respiratory humidifcation systems anaesthetic gasses on the respiratory 1997;14:368–73. Part 1 – history, approach to the theory and applications breathing system flters. Equipment 290 Anatomical differences in the Children neither look nor behave like small adults. Their requirements in the perioperative setting differ, including airway between adults and children those of anaesthetic technique and equipment. Some of the items we take for granted airway is the cricoid ring: a tube passing easily appear too simple to have been the subject of invention, an through the laryngeal inlet may be too tight at the example of this being the T-piece breathing system devel- 1 cricoid ring. Should insertion of a tracheal tube be oped from Magill’s system by Dr Phillip Ayre. Too small a tube leads to be the easiest to use, but lightly modifed, remains popular an increase in resistance, large leak, and possible with paediatric anaesthetists the world over (Fig. Too tight a ft creates The differences, both between adults and children and a risk of mucosal ischaemia and oedema, leading to within children of different ages, affect the design of stridor at extubation equipment. This is particularly so for those items relating • the larynx is smaller, so the reduction in diameter to control of the airway and breathing. Small pieces of imposed by a tracheal tube will have a signifcantly equipment designed for use on small patients, must be larger effect on airway resistance to fow. The handled by unwieldy adult hands, and be compatible with signifcance of apparatus dead space in comparison international standard fttings. Bulky equipment increases to the child’s total dead space becomes greater the the chance of technical complications, particularly acci- smaller the child (Fig. Neonates • The chest wall of the child is more compliant, and and infants present the largest variation, the older child contributes little to ventilation. For adult patients, single-use breathing systems Apparatus for management of the paediatric airway, from may be reused, provided an effective airway flter is used facemasks through to tracheostomy tubes, is outwardly to isolate the system and anaesthetic machine from trans- similar to the adult equivalent. Evidence is accumulating that paediatric in both adult and paediatric practice has been revolution- flters are as effcient as the adult versions,4 but as yet the ized by the introduction of the laryngeal mask airway. For more Similar airway management devices introduced following information see the section on breathing system humidi- the laryngeal mask have not so far enjoyed the same level fcation and fltration later in this chapter. Facemasks Regulation of equipment These should be available in a range of appropriate sizes manufacture and form a good seal at the edges, with minimal dead The development and testing of new apparatus, and its space. Clear plastic masks are less frightening to awake ease of use, have been reviewed. To turer provides details of risk analyses, performance in reduce dead space, the Rendell-Baker-Soucek mask was standard tests and technical data relating to manufacture designed anatomically, from casts of children’s faces in the same way as a dental plate is made. Other masks require some form of fexible lip devices are classifed and tested according to potential risk or air flled cushion. Disposable masks generally employ a cushion not imply specifc clinical testing; most pre-use testing is seal, the rest of the mask being of rigid construction. An urge to release a new device meeting minimum standards onto the market is balanced against the need for commercial success; this provides manufac- turers with an incentive to produce equipment with C demonstrable clinical value. As an example, the laryngeal mask whilst scaled down from adult versions was still B subject to specifc testing to confrm it retained anatomical suitability for paediatric use. Below the age of 10 years, uncuffed tracheal tubes were the norm and A were believed to minimize the chance of mucosal damage and post extubation stridor. Despite this perceived advan- B tage, the lack of an airway seal with uncuffed tubes can permit fuid to enter the tracheobronchial tree, contribute to atmospheric pollution, lead to inadequate ventilation D and induce anaesthesia in surgeons working around the upper airway. Oral north work still remains to be done, particularly on cuff position facing tube; B. Coexisting medical conditions may infuence tube size, for example: children with Down syn- drome often require a tube 1–2 mm smaller than expected for their age. Some tubes incorporate marks intended to guide how far to advance the tube into the larynx under direct vision. The placing of such marks is inconsistent across tube sizes and manufacturers, and they should not be relied upon. Flow at the interface of breathing system and tube is Tracheal tubes disturbed by changes in diameter and direction. Connec- Tracheal tubes are available in sizes and shapes to suit tors aim to minimize this by smooth internal surfaces, different patients and surgical procedures (Fig. Connectors do not reduce to each patient is determined by external diameter which the available lumen as they dilate the tube at the point varies with tube wall thickness. Endotracheal tubes allow suction to The decision to intubate, and which tracheal tube to be applied to the lower airway. Previous attempts to circum- for use, doubling the tube diameter in mm, gives the vent the problem of tube resistance included the use of appropriate French gauge catheter size. The same device locked onto the tube, self-adhesive strips (arrowed) are used to fx the device to the face. Tracheostomy tubes A full range of uncuffed tracheostomy tubes exists for use in children (Fig. To avoid endobronchial intubation, the intratracheal length is kept short; hence accidental decannulation is easily achieved. Gaining access to the airway Airway instrumentation and visualization differs in paedi- atric practice due to the anatomical differences previously mentioned. Management plans need to take account of the additional challenges posed by small and rightfully uncooperative patients. The laryngoscope procedure, compared with jet entrainment or apnoeic The larynx is usually seen with the direct laryngoscope. Care is needed with laryngeal mask cuff pres- variety of laryngoscope blade profles exist. The choice is sures, particularly if nitrous oxide is employed; unchecked usually dependent upon the age of the patient and the pressures are usually higher than expected and may injure personal preference of the anaesthetist (Fig. The little fnger of the hand holding the laryngoscope may be used to apply external Other supraglottic airway devices laryngeal pressure to improve the view. Flexible tracheal tube introducers can be used to railroad a tube into a A number of other supraglottic airways have followed in larynx when a direct view cannot be obtained. Once in 296 Equipment for paediatric anaesthesia Chapter | 12 | A A B B C Figure 12.
There is no evidence vided for national and local use including information that these fgures have changed signifcantly since then cheap macrobid 100 mg on line. Clinical correspondence with coding Electronic prescribing Medicolegal The record should be accurate generic macrobid 100mg free shipping, complete and legible macrobid 100mg, as its quality may be seen as a refection of the quality of care given cheap 100 mg macrobid. It may also protect from litigation where the onus the introduction of a computerized record. A modern computerised anaesthetic record system should also have comprehensive links to other clinical information systems to ensure that up-to-date information Computerized anaesthetic records is available, and to avoid duplicate entry of pre-existing Computerized anaesthetic record systems have been avail- information (e. Now it is anticipated that One of the diffculties in providing a business case is the ‘Clinical Five’6 (see Box 22. It – Appropriate user interface may be argued that the act of keeping a manual record – Anaesthetic preoperative assessment record focuses the attention, but this is unsupported and is out- – Validation of staff weighed by the provision of a clear detailed graphical – Capture of all patient monitor data record (Fig. Any anaesthetist keeping a manual – Capture of all machine monitor data record will be aware of the tendency during long cases – Confgurable display of all trend data for the interval between recordings to increase as the – Comprehensive data dictionary case progresses. An automatic record will maintain record- ings with the same granularity throughout – including – Rapid entry of narrative from menus times when the anaesthetist is occupied directly with the – Automatic coding patient. The latter is – Postoperative instructions now the most common scenario for electronic patient – Recovery progress record systems, generally as it is far easier to maintain. This ensures that it can continue in the – Data for audit event of a network failure, and in the event of a local – Financial analysis. However, the improved reliability of most networks and the ease of maintenance of client/ server applications will make web-based solutions more common in the future. This will normally be a keyboard or mation from the patient’s medical record to be accessible touch screen, together with some pointing device. This has now been developed and is being must all be suitable for use in the theatre, and should rolled out throughout England so the anaesthetist will be easy to clean to avoid cross infection. Washable, sealed, have online access to key features of the patient’s medical plastic-coated keyboards, which may even be cycled history, including medications and allergies. Qualifed assistant present Context, cause, effect Duty consultant informed Operating surgeon Hazard fags Operation planned/performed Warnings for future care Apparatus Check performed, anaesthetic room, theatre (Royal College of Anaesthetists Newsletter 36 (1997) – reproduced with permission. Pharmacology display systems should also adhere to a standard schema and terminol- ogy to ensure information is comparable wherever it is Decision support systems mentioned above should not collected. Response surface pharmacodynamic interaction models can be used to guide anaesthetic drug dosing. Such a system is the SmartPilot View in the main medication administration record. This can the operating theatre was, until recently, prohibited due be defned as any method that takes input information to the perceived risk of electromagnetic interference about a clinical situation and then produces inferences causing malfunction of therapeutic and monitoring that can assist practitioners in their decision-making. Thankfully this is no longer the case as it is rec- example a prescribing system (and, hence, also an anaes- ognized that the benefts of mobile phones far outweigh thetic system) should be able to give the clinician informa- the risks. It is vital that the anaesthetist can communicate tion about dosage, interactions, and alternatives on the with pre- and postoperative areas and many organizations basis of embedded knowledge about the patient and drug invest in sophisticated communication systems using (Fig. Br J Anaesth automatic record keeping on Confdential Enquiry into Perioperative 1998;80:58–62. However, in most modern electricity supply 449 diathermy machines, this plate is isolated from earth as far as mains current is concerned (see Chapter 24). However, because the live cable is Most electromedical devices, including anaesthetic appa- still functioning, any contact with the (‘live’) casing would ratus and monitors, are powered by mains electricity. These frequencies may be a good choice for 60601-1, lays down quite specifc testing regimens for power transmission, but they are more hazardous to the electromedical equipment before use. It also shows how these secondary 240 V within the monitor (2) to render the apparatus dangerous windings are linked together and connected to earth at the to the patient. This may be installed in the mains Because of this earthing of the neutral conductor at the supply circuit, in the plug of the electrical lead to the appa- power station, any person or object who is also connected ratus, or in the apparatus itself. Power station transformer reduction of three Earth phase 16 kV supply to 240V supply. However, there is a risk that the fuse may not protect injury are tissue resistance (R), current (I), potential dif- against electric shock. This can happen if someone is in ference (V), current frequency, current pathway and dura- contact with the equipment as the fault develops and before tion and current density. Fuses are used mainly the tissues depends on the power dissipated (P), which to interrupt the electric supply in the event that the current can be calculated from: passing through the equipment exceeds a predetermined 2 P = V × I = I R level that might cause overheating or damage. The body may be considered electrically to be an elec- trolyte (a good conductor) in a leathery bag (a poor con- ductor, an insulator). At low voltages, 25–100 volts, it depends similar current fows on the state of the skin and area of contact. At 250 volts • produces continuous muscle contractions (tetany) at and higher, the total body impedance falls to 2000–5000 40–110 Hz ohm, irrespective of the contact area and the current • induces grip and pull as fexor muscles are much pathway. If a person were to The effects of electric current upon excitable tissues such be holding onto a faulty conductor, he would be as muscle and nerve depend not only on current and time, unable to let go. Clinical studies suggest that sudden death from As indicated above, there are four ways in which the mains ventricular fbrillation is more likely with current passing electric current, or equipment powered by it, endanger the ‘horizontally’ from hand to hand, whereas heart muscle patient. These are: 449 Ward’s Anaesthetic Equipment Cannot let go Pain and asphyxia ( > 50 mA ) 1+mA Tingling sensation 15+mA 240 V Slow death A B Rapid death 75–100+mA Ventricular fibrillation C Figure 23. A current in excess of 1 mA passing through the body may produce a tingling sensation. If the current exceeds about 15 mA, muscles are held in tonic spasm, the victim cannot let go and will eventually die of asphyxia. When the current exceeds 100 mA, ventricular fbrillation and rapid death will occur. This difference in potential along the • electrochemical effects neutral lead may facilitate stray capacitative or inductive • ignition of fammable materials. Similarly, earthed electrodes may be attached to more than one part of the patient and from more than one piece of equipment supplied by different mains Electrocution sockets, which may also facilitate stray capacitative or inductive currents in a circuit, which includes the patient. Therefore, it is recommended relatively slowly by tonic contraction of the respiratory that the earth connections on all the socket outlets in a muscles, leading to asphyxia, or more rapidly by ventricu- single clinical area be interconnected by a low-resistance lar fbrillation. The onset of ventricular fbrillation may be conductor to minimize voltage differences between them. As discussed earlier, the neutral pole of the mains elec- Microshock tricity supply is connected to earth at the star point, a point at the power station which is thus remote from the patient. The patient end of medical, surgical and critical care procedures involve the 450 Electrical hazards and their prevention Chapter | 23 | 10000 1 2 3 4 5 5000 2000 1000 500 200 100 50 30 20 0. Zone 1, usually no effect; zone 2, usually no dangerous effect; zone 3, usually no danger of ventricular fbrillation; zone 4, ventricular fbrillation possible; zone 5, ventricular fbrillation probable. Under these circumstances, a very much smaller current, possibly as low as 100 µA, can result in ventricular fbrillation (Fig. A very small potential, such as the stray voltage in the mains neutral lead, could be suffcient to produce electrocution in this way. Installing an isolating transformer, the output of diathermy which is carefully isolated from earth Resistance between 2. Detecting unwanted currents passing to earth by a different earth points device that will sound a warning or automatically switch the supply. Should earth leakage occur above a pre-arranged level, the relay will either disconnect the supply to the input of the transformer or sound a warning device. It may be manually reset and may also have a test that the output from the transformer is free from earth. The sum of all these currents may be by a high standard of earthing of the fxed wiring, by suffcient to trip the relay and cut off the power to a good earthing of enclosures and fully foating patient cir- monitor or other mains powered anaesthetic equipment. Safety may be further improved Likewise, a fault in one piece of apparatus may cause the by using battery-operated equipment. If the relay operates an alarm battery may be recharged from the mains between uses. A better alternative is to include a small isolating trans- former in the circuitry of each individual item of mains Classifcation of electromedical operated electromedical equipment, which can be con- equipment to ensure nected to the patient. The patient circuit is, therefore, 1,8 electrical safety earth-free and said to be fully foating. The enclosure of the equipment may be earthed (or completely insulated The international standard governing electromedical see below). This may be installed in the electrical patient or, indeed, the operator of the equipment, so that supply to the whole operating room or theatre suite, or even if one level fails, harm may yet be avoided.
More recent data from California and New York do not support an increase in infective endocarditis with the current approach to prophylaxis generic macrobid 100 mg line. Meningococcus (Neisseria For prophylaxis of close contacts generic 100mg macrobid amex, including house- A single dose of ciprofloxacin should not present a signifi- meningitidis)15 discount 100 mg macrobid with amex,16 hold members order macrobid 100 mg visa, child care center contacts, and cant risk of cartilage damage, but no prospective data anyone directly exposed to the patient’s oral exist in children for prophylaxis of meningococcal dis- secretions (eg, through kissing, mouth-to-mouth ease. For a child, an equivalent exposure for ciprofloxacin resuscitation, endotracheal intubation, endotra- to that in adults would be 15–20 mg/kg as a single dose cheal tube management) in the 7 days before (max 500 mg). Close con- tact can be considered as face-to-face exposure within 3 feet of a symptomatic person; direct contact with respi- ratory, nasal, or oral secretions; or sharing the same con- fined space in close proximity to an infected person for $1 h. Azithromycin and clarithromycin are better tolerated than erythromycin (see Chapter 5); azithromycin is preferred in exposed very young infants to reduce pyloric stenosis risk. Antimicrobial Prophylaxis/Prevention of Symptomatic Infection Antimicrobial Prophylaxis/Prevention of Symptomatic Infection A. Neonatal: Following symp- See recommendations in Section C of this chapter (Table 14C). Bites of squirrels, hamsters, guinea pigs, gerbils, chip- munks, rats, mice and other rodents, rabbits, hares, and pikas almost never require anti-rabies prophylaxis. For bites of bats, skunks, raccoons, foxes, most other carni- vores, and woodchucks, immediate rabies immune glob- ulin and immunization (regard as rabid unless geographic area is known to be free of rabies or until ani- mal proven negative by laboratory tests). However, antimicrobial prophylaxis may alter the nasopharyngeal flora and foster colonization with resistant organ- isms, compromising long-term efficacy of the prophylactic drug. Although prophylactic administration of an antimicrobial agent limited to a period when a person is at high risk of otitis media has been sug- gested (eg, during acute viral respiratory tract infection), this method has not been evaluated critically. Early treatment of new infections is recom- mended for children not given prophylaxis. Resistance eventually develops to every antibiotic; follow resistance patterns for each patient. Anecdotally, some children may children quent recurrence (no pediatric data): require tid dosing to prevent recurrences. Antimicrobial Prophylaxis/Prevention of Symptomatic Infection Antimicrobial Prophylaxis/Prevention of Symptomatic Infection D. The virulence/pathogenicity of bacteria inoculated and the presence of foreign debris/devitalized tissue/surgical material in the wound are also considered risk factors for infection. For all categories of surgical prophylaxis, dosing recommendations are derived from (1) choosing agents based on the organisms likely to be responsible for inoculation of the surgical site; (2) giving the agents at an optimal time (,60 min for cefazolin, or ,60 to 120 min for vancomy- cin and ciprofloxacin) before starting the operation to achieve appropriate serum and tissue exposures at the time of incision; (3) providing addi- tional doses during the procedure at times based on the standard dosing guideline for that agent; and (4) stopping the agents at the end of the procedure or for no longer than 24–48 h after the end of the procedure. Bathing with soaps or an antiseptic agent the night before surgery is recommended, with alcohol-based presurgical skin preparation. Begin postoperative prophylaxis 30 mg/kg at 8 h after intra- operative rewarming dose. Giardia intestinalis (formerly Giardia lamblia and Giardia duodenalis) infections. American Association for the Study of Liver Diseases, Infectious Diseases Society of America. See AmB deoxycholate (AmB-D) Acinetobacter spp, 21, 130–131 AmB deoxycholate (AmB-D). See AmB deoxycholate neonates, 51 (AmB-D) obese children, 242 dosage form/usual dosage, 214 Anthim, 226 fungal pathogens, 156–157 Anthrax, 63, 119 L-AmB. See Liposomal amphotericin B Anthrax meningoencephalitis, 119 (L-AmB) Antibiotic(s). See Candidiasis Famciclovir chromoblastomycosis, 166 dosage form/usual dosage, 222 coccidioidomycosis, 166–167 viral pathogens, 174 cryptococcosis, 168 Famvir, 222 dermatophytoses, 172 Fasciola hepatica, 200 fungal pathogens, 156–157 Febrile neutropenia, 120–121 histoplasmosis, 170 Fetal risk, 56 hyalohyphomycosis, 168–169 Fifh-generation cephalosporins, 3 localized mucocutaneous infections, 172 Filariasis, 198–199 mucormycosis, 170–171 First-generation cephalosporins, 2 newborns, 32–35 Flagyl, 225 paracoccidioidomycosis, 171 Flavivirus, 113 phaeohyphomycosis, 160 Floxin Otic, 239 Pneumocystis jiroveci pneumonia, 171 Fluconazole prophylaxis, 158, 255 azole, 11–12 sporotrichosis, 171 dosage form/usual dosage, 222 systemic infections, 158–171 fungal pathogens, 156–157 tinea infections, 172 neonates, 53 Fungal pathogens, 156–157. See also Diarrhea Gram-negative bacteria, 131 Gastrointestinal anthrax, 119 neonates, 55 Gastrointestinal infections, 101–107 obese children, 241 abdominal tuberculosis, 106 Gentamicin 1 prednisolone, 237 antibiotic-associated colitis, 103 Giardia spp, 190 appendicitis, 106 Giardia intestinalis, 104, 200–201 diarrhea. See Cytoisospora belli Legionella spp, 143 Itraconazole Legionella pneumophila, 90 azole, 12 Legionnaires disease, 90 dosage form/usual dosage, 223 Leishmania spp, 202–203 fungal pathogens, 156–157 Leishmaniasis, 202–203 Ivermectin Lemierre syndrome, 79, 99 dosage form/usual dosage, 223, 237 Leprosy, 121 parasitic pathogens, 190–191 Leptospira spp, 143 Leptospirosis, 122 J Letermovir, 174, 224 Jock itch (tinea cruris), 172 Leuconostoc, 143 Jublia, 236 Levaquin, 224 304 — Index Levofoxacin pertussis, 83 dosage form/usual dosage, 224, 237 pneumonia. See also Newborns Mycamine, 225 Metronidazole Mycelex, 219 anaerobes, 133 Mycobacterial pathogens. See Bacterial and dosage form/usual dosage, 225, 238 mycobacterial pathogens 306 — Index Mycobacterium abscessus, 144 Neisseria gonorrhoeae, 146 Mycobacterium avium complex Neisseria meningitidis, 114, 130–131, 146 description of, 144 Neomycin 1 polymyxin B 1 hydrocorti- pneumonia, 90 sone, 236 Mycobacterium bovis, 106, 115, 144 Neomycin 1 polymyxin 1 dexamethasone, Mycobacterium chelonae, 144 237 Mycobacterium fortuitum complex, 145 Neomycin sulfate, 225 Mycobacterium leprae, 145 Neonatal therapy. See Bacterial and mycobacterial creeping eruption, 196 pathogens cryptosporidiosis, 196 fungal, 156–157 cutaneous larva migrans, 196 parasitic. See Francisella tularensis, 88 Antimicrobial prophylaxis Histoplasma, 88 Prevotella spp, 147 immunosuppressed, 86 Prevotella melaninogenica, 147 infuenza virus, 89 Prevymis, 224 interstitial pneumonia syndrome of early Prifin, 230 infancy, 86 Primaquine phosphate, 229 Klebsiella pneumoniae, 89 Primaxin, 223 Legionnaires disease, 90 Proctitis, 108 Mycobacterium avium complex, 90 Prophylaxis of infections. See Genital and sexually transmitted late latent, 110 infections neurosyphilis, 110 St. Choosing Among Antibiotics Within a Class: Beta-lactams and Beta-lactamase Inhibitors, Macrolides, Aminoglycosides, and Fluoroquinolones 2. How Antibiotic Dosages Are Determined Using Susceptibility Data, Pharmacodynamics, and Treatment Outcomes 4. Approach to Antibiotic Therapy of Drug-Resistant Gram-negative Bacilli and Methicillin-Resistant 2019 Staphylococcus aureus 5. Sequential Parenteral-Oral Antibiotic Therapy (Oral Step-down Therapy) for Serious Infections David W. Nutrition and infection are often at cross-roads interacting with each other, infu- encing human health in a way that has implications for both the developed and developing world. Infectious morbidity is huge in the malnourished, both in the def- cient and excess nutritional states. Infections, both systemic and gastrointestinal, signifcantly affect enteral nutrition and absorption. A book that describes nutrition– infection interactions is not only extremely useful but also essential for health-care staff, nutritionists, and epidemiologists. We strongly believe that such a book will not only improve care of patients in health-care facilities but also the health of the vulnerable population. The book’s frst chapter explores the role of nutrition in health and disease, espe- cially the effects of malnutrition, both undernutrition and overnutrition. We then describe the relation between malnutrition and immunity followed by a chapter exploring micronutrient defciency and immunity. The concept of nutrition–infection interaction pertaining to the developing world in transition is introduced. The fnal common pathway for many human diseases may be unbalanced infammation and oxidant injury. A chapter discussing the role of oxidant stress and therapy with antiox- idants explores the infammation concept. An interesting link in nutrition–infection interactions is how nutrients and drugs interact, both anti-infective drugs and others. We devote the next few chapters to nutrient–infection interactions in specifc infections. We discuss the interactions in human immunodefciency virus, tuberculosis, malaria, and parasitic infections, with special emphasis on nutritional interventions. The role of the gastro- intestinal tract and its infuence on nutrition, focusing on the human gastrointestinal microbiota and enteric syndromes, are presented next. The human gastrointestinal microbiome is essential in the maturation of immune responses and prevention of pathogen colonization, both of which infuence infectious risk. The pattern of gastrointestinal microbiota is altered by the dietary intake and conversely alters dietary components, which in turn affect nutrient absorption and immune responses. Modifying indigenous microbiota for health benefts is discussed in the chapter on probiotics and prebiotics. Current research lays emphasis on immunonutrients that can enhance immunity and prevent infections, and a chapter that discusses immu- nonutrients has been included. We also discuss infection–nutrition interactions in special age groups: children, adolescents, and the elderly. We close the book with a review on nutritional and anti-infective strategies emerging from the horizon and identify future research directions. We have kept in mind the broad audi- ence to this book and hence tailored to enhance the book’s applicability to both the developed and the developing world. We sincerely hope that we have conveyed our perspective on nutrition–infection interactions to everyone’s beneft.
The hemostasis laboratory technologist performs a mixing study on a plasma specimen from a 13-year- old Caucasian female of European descent with complaints of easy bruising cheap macrobid 100 mg fast delivery, menorrhagia trusted 100mg macrobid, and frequent epistaxis discount macrobid 100 mg amex. If the initial mix result indicates correction cheap macrobid 100mg, the assay is repeated after a 1–2 h incubation at 37°C. Most specifc inhibitors are of IgG isotype and are time- and temperature-dependent. In either event, for this case, it does not matter because the immediate and incubated mixing study results indicate correction, implying a factor defciency. Anticardiolipin antibody assay would not be contributory in a bleeding patient, but is sometimes performed in patients with thrombosis (Answer E). Failure to correct the prolonged clot time when mixing with normal platelet-poor control plasma and repeating the test (i. Shortening or complete correction of the prolonged screen assay result by addition of a reagent formulated with excess phospholipidsa 4. Which immunoassay is the most reliable in supporting the diagnosis of antiphospholipid antibody syndrome? Answer: B—Anti-β2-glycoprotein I antibody assay is the best choice among the given options. Answer: D—Enoxaparin is a low molecular weight heparin, as are dalteparin and tinzaparin. These preparations are effective and safe, and may be self-administered subcutaneously daily throughout pregnancy. Factors X and V Concept: The two most common acquired coagulopathies are liver disease and vitamin K defciency. Thus, it is the frst to be affected by warfarin therapy, vitamin K defciency, or liver disease. Factor V is chosen because it is not vitamin K-dependent, and its activity level diminishes in liver disease but not in vitamin K defciency. The platelet count or platelet functional assays (Answer B) and D-dimer (Answer A) are also unreliable since changes may be related to a variety of disorders. Microthrombi are gradually degraded through fbrinolysis, in which plasmin digests the fbrin clot, forming an array of fragments called fbrin degradation products, labeled D, E, X, and Y. Several manufacturers have developed kits that employ D-dimer-specifc monoclonal antibodies. Although most coagulation factors are diminished, the most consistent abnormal laboratory result is the D-dimer level that may be elevated to 50–100 times the reference range limit, indicating ongoing fbrinolysis. Platelet aggregometry and factor assays are high-complexity tests, whereas the D-dimer is an automated assay available in acute care facilities with a relatively quick turnaround time. A patient being prepared for a valve replacement undergoes a platelet aggregometry test with the following results: Agonist Percent aggregation Reference interval Arachidonic acid 18% Thrombin 85% > 65% for all agonists Collagen 41% Ristocetin 71% What is the most likely reason for these results? Thrombin is the most avid agonist; it also binds a specifc platelet membrane receptor and triggers full aggregation and platelet secretion. Because aspirin irreversibly acetylates platelet cyclooxygenase, the frst of several enzymes in the eicosanoid synthesis pathway, arachidonic acid fails to be converted to thromboxane A2, a platelet-activating product, reducing aggregation. When drug ingestion is excluded, the clinician may diagnose the uncommon platelet secretion (aspirin-like) disorder. This is a hereditary reduction of one of the eicosanoid synthesis pathway enzymes that suppresses platelet activation and reduces platelet secretions. The effect of aspirin is also partially expressed in a decreased response to collagen. Since the results show response to thrombin and collagen, it is unlikely to be Glanzmann thrombasthenia (Answer D) (Figs. Ristocetin-induced agglutination is reduced in Bernard-Soulier syndrome and severe von Willebrand disease (Figure 13. The transfusion service technologist prospectively reviews the order and calls the pathology resident. Her bleeding is more likely due to an inherited platelet defect, and platelet transfusion is indicated C. There is no evidence of hemostatic abnormality and her oozing is likely due to a localized problem Concept: The type of bleeding and the patient’s clinical history are often more informative in the construction of the differential diagnosis than the results of the initial coagulation assays. While patients sometimes have unexpected bleeding without an abnormal laboratory test result, others have laboratory abnormalities that are unrelated to the bleeding. Answer: C—Goodpasture syndrome (or Goodpasture disease) is an acquired fulminant autoimmune disorder of unknown origin characterized by the development of antiglomerular basement membrane collagen autoantibodies that cross-react with the collagen of pulmonary alveoli. Goodpasture syndrome causes acute glomerulonephritis with renal failure and pulmonary hemorrhage. Decreased platelet function causes a characteristic mucocutaneous bleeding diathesis that may require systemic treatment (Answer E). As a follow-up, you suggest a complete blood count for the Goodpasture syndrome patient. The anemia is probably due to iron defciency and should be treated with oral iron supplementation B. She has a signifcant risk of hemoptysis and should be given a platelet transfusion to prevent bleeding D. The correlation between the hematocrit and uremic platelet dysfunction suggests that increasing the platelet count is useful E. Additionally, donor platelets will become dysfunctional by the same mechanism (incompletely described) as the patient’s own platelets, so platelet transfusions are contraindicated (Answers C and D) unless there is life-threatening bleeding in the absence of response from all other measures. With no evidence of massive bleeding, transfusing in a 1:1:1 ratio is not indicated (Answer E). The mother was receiving unfractionated heparin Concept: Preop laboratory tests are unnecessary in the absence of a bleeding history, though they are often ordered. Since congenital heart defects often cause hepatic congestion and the liver produces most of our coagulation factors, testing this child is warranted. Newborns’ expected factor levels differ from adults, making it essential to interpret their test results with age-matched reference ranges. Cryoprecipitate is unlikely to provide the necessary coagulation factors and plasma brings the risk of circulatory overload (Answer D). The surgeon consults with the pediatric hematologist who orders various factor activity level assays. His liver is affected by severe congestion and he should receive preoperative plasma D. These factor levels are expected for a newborn and he is not at increased risk of bleeding E. Answer: D—These factor levels are expected for a newborn and he is not at an increased risk of bleeding. Their slight elevation in this case may be an acute response to infammation, but do not signal thrombotic risk in a newborn (Answer E). The parents of a 1-year-old boy report that he has begun to experience episodes of severe pain in his ankles and knees since beginning to walk. The immediate and 2-h incubated mixing study corrections indicate a factor defciency. This patient’s clinical symptoms are not typical for a platelet disorder, which usually manifests with mucocutaneous bleeding (Answer A), as compared to his joint bleeding. Because the calibrator is diluted 1:10, the frst patient’s plasma dilution is 1:10 and is paradoxically considered “undiluted” for computation purposes. If all the dilutions generate results within 10% of the frst result after multiplying by their respective dilution factors, the results are deemed “parallel,” the assay is validated, and there is no inhibitor (Table 13. The identical results for dilutions 1:80 and 1:160 indicate that the inhibitor has been “diluted out. Based on the results, this is not an adequate response to the dose given (Answers A and B). Lupus anticoagulant (Answer D) may generate similar nonparallel dilution results and must be considered in the laboratory differential identifcation; however, the patient’s diagnosis is long-established. These results do not imply the possibility of a second factor defciency (Answer E). Based on these results and the clinical history, what is the most likely diagnosis for this patient?
Physical examination is often unrewarding but it may disclose a hepatic purchase macrobid 100mg line, rectal discount 100mg macrobid with mastercard, or pelvic source for the diarrhea; it may also indicate that the diarrhea is a sign of a systemic disease (e buy 100mg macrobid free shipping. A warm stool examination for pus generic 100mg macrobid with visa, pH (acid stool suggests lactase deficiency), fat and meat fibers, blood, ova, and parasites is most essential. Colonoscopy and biopsy (ulcerative colitis, amebic colitis, 270 granulomatous colitis) 11. Perinuclear-staining of anti-neutrophil cytoplasmic antibodies (ulcerative colitis) Case Presentation #15 A 54-year-old white man complained of chronic diarrhea for the past year. He had also noted frequent indigestion and heartburn and occasional midepigastric pain. Utilizing the methods provided above, what is your list of possibilities at this point? Further history reveals that he has had occasional black stools and does not abuse alcohol or drugs. His physical examination is unremarkable, but stools test positive for occult blood. Mechanical obstruction may result from intrinsic disease of the pharynx, larynx, and esophagus or extrinsic disease of the organs around the esophagus. I—Inflammatory should suggest pharyngitis, tonsillitis, esophagitis, and mediastinitis. N—Neoplasm should bring to mind esophageal and bronchogenic carcinoma, and dermoid cysts of the mediastinum. D—Degenerative and deficiency disease should suggest Plummer– Vinson syndrome or iron deficiency anemia. C—Congenital and acquired anomalies should suggest esophageal atresia and diverticula. T—Trauma would prompt the recall of ruptured esophagus, pulsion diverticulum, and foreign bodies that obstruct or injure the wall of the esophagus. Table 23 Diarrhea—Physiologic Classification E—Endocrine disorders suggest the enlarged thyroid of endemic goiter and Graves disease. Physiologic obstruction results from neuromuscular disorders at the end organ, myoneural junction, and lower and upper motor neurons. End organ: This should suggest myotonic dystrophy, dermatomyositis, achalasia, and diffuse esophageal spasm. Lower motor neuron: In this category one would recall poliomyelitis, diphtheritic polyneuritis, and brainstem tumors or 272 infarctions. It should also bring to mind Parkinson disease and other extrapyramidal disorders. Approach to the Diagnosis The age of onset is significant because carcinoma of the esophagus is rare before age 50, whereas achalasia and reflux esophagitis are more common in young and middle-aged adults. The onset is gradual in carcinoma and aortic aneurysms but more acute in reflux esophagitis and foreign bodies. Patients with achalasia have trouble swallowing both food and water, but those with carcinoma suffer the most, and often the only difficulty is swallowing food. Neurologic findings will focus on the diagnosis of bulbar and pseudobulbar palsy whereas hematemesis and heartburn will suggest esophageal carcinoma or reflux esophagitis. However, esophagoscopy and biopsy will lead to a definitive diagnosis in most cases of mechanical obstruction. If esophagoscopy is negative, one may resort to a Mecholyl test to diagnose achalasia, a Tensilon test to exclude myasthenia gravis, and esophageal manometry to diagnose reflux esophagitis, scleroderma, and diffuse esophageal spasm. Difficulty urinating must be distinguished from dysuria (page 148), which is painful urination, and anuria or oliguria (page 60), which is absent or reduced volume of urine. If we then visualize the urinary tree from the prepuce on up to the bladder, we can visualize the causes of obstruction at each level. Prepuce—Phimosis and paraphimosis Meatus—Meatal stricture Urethral—Urethral stricture, urethral calculus Prostate—Prostatitis, prostatic hypertrophy, prostatic carcinoma, prostatic calculus Bladder—Bladder neck obstruction due to stricture, median bar hypertrophy, calculus or neoplasm Extrinsic lesions of the bladder or urethra—Uterine fibroids, pregnant retroverted uterus, or carcinoma of the vagina Lesions of the innervation of the bladder wall—This may be due to lower motor neuron disorders such as poliomyelitis, cauda equina tumors, or disks; tabes dorsalis; or diabetic neuropathy. Approach to the Diagnosis The first thing to do is to establish that there is an obstruction to the flow of urine. This may now be done with ultrasonography, but catheterization may still be done in the acute situation. Difficulty voiding in a young person will most likely point to a urethral stricture or prostatitis from previous gonorrhea or urethral injury, whereas difficulty voiding in an older man would suggest prostatic hypertrophy. A history of hematuria would suggest the possibility of a vesicle or urethral calculus. A complete physical including a rectal and pelvic examination (in women) is done next. If these tests are negative, an urologist needs to be consulted for cystoscopy and cystometric testing. A dilated pupil, however, may also signify a lesion of the optic nerve and its pathways. Lesions of the oculomotor nerve and pathways End organ: Lesions of the eye that cause dilated pupils include glaucoma, high myopia, anticholinergic drugs (e. Peripheral portion of the oculomotor nerve: Important lesions here include aneurysms of the internal carotid artery and its branches; herniation of the brain in brain tumors, subdural hematomas, and other space-occupying lesions; cavernous sinus thrombosis; sellar and suprasellar tumors; tuberculosis and syphilitic meningitis; and sphenoid ridge meningiomas. Diabetic neuropathy of the third cranial nerve does not usually 275 cause mydriasis. Most of these lesions are associated with ptosis and paralysis of the other extraocular muscles supplied by the oculomotor nerve. Barbiturates and other drugs may cause dilated pupils by their central nervous system effects. Optic nerve and pathways End organ: Keratitis, cataracts, retinitis, and occlusion of the ophthalmic artery are included here. Peripheral portion of the optic nerve: Aneurysms; optic neuritis; sellar and suprasellar tumors; optic nerve gliomas; primary optic atrophy from lues and other conditions; orbital fractures; exophthalmos; and cavernous sinus thrombosis are recalled in this category. Brainstem: The lesions involving the optic tract here are similar to those that involve the oculomotor nerve discussed above. Optic cortex (calcarine fissure) lesions may cause blindness, but there is no mydriasis. Approach to the Diagnosis The clinical picture will often help to pinpoint the diagnosis. Unilateral dilated pupil with ptosis would suggest oculomotor palsy, which may be due to a cerebral aneurysm or tumor or other space-occupying lesion. Early compression of the oculomotor nerve by a subdural hematoma or other mass may be indicated by a dilated pupil. Diabetic neuropathy may cause ptosis and extraocular muscle palsy without a dilated pupil. Unilateral or bilateral dilated pupils with blurred vision may be due to glaucoma or iritis. A dilated pupil with other neurologic findings is a clear indication for referral to a neurologist or neurosurgeon. He or she may be able to do tonometry to rule out glaucoma and a slit lamp examination to evaluate for iritis and other conditions. Mecholyl test (Adie pupil) Case Presentation #16 A 26-year-old Hispanic man came to the emergency room complaining of drooping of the right eyelid and double vision. Further history reveals that he has had frequent headaches for the past week, and neurologic examination revealed nuchal rigidity in addition to the right oculomotor palsy. The causes of lightheadedness are developed under the section on syncope (see page 404). The diagnostic approach to dizziness or true vertigo uses anatomy, beginning with the external ear and working inward toward the middle ear, labyrinth, auditory artery and nerve, and vestibular nuclei in the brainstem. Otitis media, especially when it invades the mastoid or petrous bone, is the most important cause of vertigo in the middle ear. If the drum is perforated, however, or if there is a perforation into the perilymph system, vertigo will occur, especially when water enters the ear. The inner ear is the site of two important causes of vertigo: acute labyrinthitis and Ménière disease.
Eur Inﬂammatory diseases of the aorta are associated with sys- Radiol 2006; 16: 676−684 cheap macrobid 100mg on-line. Cardiac imaging tis buy 100 mg macrobid mastercard, Bechet’s disease purchase macrobid 100 mg on line, giant cell aortitis discount macrobid 100mg without a prescription, Kawasaki disease, using gated magnetic resonance. Radiology 1985; tis are common in Asian countries and rare in Caucasian 155: 681−686. Radiology 1995; 195: which can lead to vascular stenoses, aneurysms of the 297-315. Quantitation of collateral blood flow in coarctation of the aorta by velocity encoded cine magnetic resonance imaging. Gadolinium- lar structures, especially between the lumen and the ves- enhanced 3D magnetic resonance angiography of the sel wall, without radiation exposure. Radiology 1997; or without the administration of intravenous contrast, 202: 183–193. Magnetic resonance helpful for prompt, accurate diagnosis of congenital and imaging of congenital abnormalities of the thoracic aorta. Demonstration of procedure times, lack of true real-time monitoring, and coarctation of the aorta by magnetic resonance imaging. Cine magnetic resonance imaging for evaluation of anatomy and flow rela- References tions in infants and children with coarctation of the aorta. Eur Radiol 2006; balloon angioplasty of coarctation restenosis by magnetic 16: 852−865. Dissection of the a “cost-effective” approach to identify complications in thoracic aorta: pre- and postoperative findings of turbo- adults. Am Heart 1994; 128: ization of human thrombus using a novel fibrin-targeted 1210–1217. J Interv Cardiol 2005; 18: nance evaluation of atherosclerotic plaques in the human 193−200. Improved progno- nance evaluation of atherosclerotic plaques in the human sis of thoracic aortic aneurysm: a population based study. Ultrasound propagates poorly through bone Echocardiography is a diagnostic technique that uses or air-ﬁlled tissue, such as lung, that eﬀectively blocks the ultrasound to image cardiac and vascular structures [1−3]. The amplitude of the returning frequency of the reﬂected sound wave is shifed based on ultrasound signal provides information on the charac- the speed of the moving object. The time it takes for used to calculate the speed of the moving object relative a transmited impulse to return is used to calculate the to the transducer. In practice, ultrasound scatering from distance between the transducer and the acoustic inter- blood cells within the heart or blood vessels can be used to face. Modern ultrasound transducers with piezoelectric quantify the velocity of blood ﬂow toward or away from elements are able to scan a two-dimensional (2D) sector the ultrasound transducer. Transmiting ultrasound in by aiming the ultrasound beam into tissue over a deﬁned pulsed waves, that is, pulsed Doppler imaging, provides arc. Transmission and recording of ultrasound pulses depth resolution of blood ﬂow velocities, but the maxi- over this 2D sector generates a cross-sectional image of mum velocity of blood ﬂow that can be quantiﬁed is lim- underlying structures. Combining pulsed phy describes the technique of continuous transmission Doppler imaging with 2D sector scanning can be used to and recording of ultrasound pulses over time over a 2D generate a 2D map of blood-ﬂow velocities superimposed sector to generate images in real time and display the on the anatomic cross-section. In color Doppler ﬂow structures using ultrasound imaging is generally twice the imaging, the color red is generally used to indicate blood distance of the ultrasound wavelength. Transducers with ﬂow toward the transducer and blue as blood ﬂow away a frequency of 2. The ability intensity of the colors are used to indicate the velocity of to image structures at diﬀerent depths from the transducer blood ﬂow. In contrast to pulsed Doppler echocardiog- is dependent on the ability of ultrasound to penetrate the raphy, continuous wave Doppler echocardiography pro- biologic medium. The amount of sound energy lost or vides a means of quantifying high velocity blood ﬂow, but atenuated as it passes through tissue, through absorption has limited ability to resolve the depth of the returning and scatering, is dependent on the ultrasound frequency signals on the sector scan. Low-frequency Two-dimensional echocardiography provides anatomic transducers provide beter penetration and imaging of information about the heart and vascular structures. In contrast, high-frequency trans- echocardiography to quantify blood-ﬂow velocities and ducers provide beter resolution of structures close to the generate a blood-ﬂow velocity map within the heart and transducer in sector scans with a smaller depth of ﬁeld. Epicardial echocardi- in examination of the entire aorta, especially in emergency ography is performed also with a hand-held ultrasound situations’. The The echocardiographic examination of the thoracic close proximity of the thoracic aorta to the esophagus and aorta can be performed using three separate techniques: favorable acoustic windows provided high-resolution images of almost the entire thoracic aorta. These early sys- Aortic intramural hematoma tems also had limited capability for performing Doppler Aortic rupture echocardiography. Arrows point to left common carotid artery (top arrow) and left subclavian artery (bottom arrow). The term ‘short axis’ indicates that the The anatomic cross-section displayed on any given imaging plane is oriented perpendicular to the direction echocardiographic image can be deﬁned by the location of blood ﬂow through the structure being imaged. The aortic isthmus is the proximal of blood ﬂow within the structure being imaged. The descending aorta between the origin of the lef subclavian multiplane angle of rotation used to generate the anatomic artery and the ligamentum arteriosum and a common cross-section provides additional information about site for aortic coarctation, patent ductus arteriosus, or the imaging plane. Calciﬁcation produces specular echoes appear- the aortic root, ascending aorta, aortic arch and descend- ing as bright areas within the image which block or cause ing aorta (Figure 7. Thrombus within a valve annulus, aortic valve, sinuses of Valsalva and blood vessel has a greater echo-density compared to blood. The ascending aorta contin- Blood stasis or low-ﬂow states within the cardiac chambers ues superiorly to the origin of the innominate artery. Fluid outside the descending aorta in carotid artery, and lef subclavian artery, extending pos- the pleural cavity may indicate pleural eﬀusion or hemo- teriorly and laterally, ending in the lef pleural cavity thorax. Fluid within the pericardium causing compression immediately distal to the origin of the lef subclavian of the cardiac chambers indicates cardiac tamponade. Hypertension in response to esophageal intubation in an incompletely anesthetized patient may also increase the risk of aneurysm rupture or hemodyamic decompensation. Compression of the right ventricular outﬂow tract may precipitate cardiogenic shock. At this level, 30−60° multiplane rota- tion provides an image of the aortic valve in short-axis (Figure 7. The mid-esophageal short-axis view of the aortic valve at a multiplane angle of 30−60° permits imag- ing of the aortic valve and aortic valve cusps. Slight ante- ﬂexion of the probe tip brings the imaging plane through the sinuses of Valsalva and the ostia of both coronary arter- ies can normally be visualized. The short-axis view of the aortic valve can be used to determine the number of aortic valve cusps, assess cusp opening and calciﬁcation, or detect Figure 7. Color-flow the presence of an intimal ﬂap caused by aortic dissection Doppler sector (blue lines) surrounds aortic valve. Color Doppler ﬂow imag- flow (blue jet) detected between the three cusps during diastole. This short- the lef ventricular outﬂow tract in diastole, or the presence axis view of the ascending aorta permits the diameter of of an intimal ﬂap in the aortic root and its relation to the the ascending aorta at the level of the right pulmonary suspension of the aortic valve cusps (i. Color Doppler vides the mid-esophageal ascending aorta long-axis view imaging in the aortic valve long-axis image can be used to (Figure 7. The inability to reliably image the dis- scan the entire descending thoracic aorta in short-axis tal ascending aorta and proximal aortic arch represents one view. At any level, multiplane rotation to 90° provides of the major limitations of transesophageal echocardiogra- a long-axis image of the descending aorta (Figure 7. Anterior wall is of the left subclavian artery and the long-axis image of the pulmonary closest to the probe. The upper esophageal aortic arch tive repair of descending thoracic aortic aneurysms. Multiplane rotation to 90° generates the determine the feasibility of endovascular stent repair. Aortic to the right images the mid- or proximal aortic arch in short dissection conﬁned to the descending thoracic aorta can axis. Recently, the sensitivities of the four imag- experienced in the diagnosis of aortic dissection.
When the one turned to is also in a nurturing role macrobid 100mg discount, this second injury becomes a component of betrayal trauma generic 100mg macrobid with mastercard. Later in adulthood generic macrobid 100mg, when an institution does not respond and instead scapegoats the victim buy macrobid 100 mg without a prescription, supports the perpetrator, and covers up the occurrence, institu- tional betrayal is said to occur—the betrayal trauma of adulthood. Nachträglichkeit, a concept coined by Freud (1914) over a century ago, is another sort of second injury—a generic, repetitive additional effect that crosses the spec- trum of trauma and neglect. It was clumsily translated into English by Strachey as “deferred action” (literally, afterwardsness), and cleverly translated into French by Rudolphe Loewenstein (1991) as après coup, or “aftershock” (or knock, blow, bump, strike, etc. Loewenstein’s analysand, Jacques Lacan, made it a central concept in French psychoanalysis. Après coup occurs whenever personal maturation (especially puberty) or new knowledge or life experience occasions a revision of past experi- ence. For example, sexual molestation by a parent at a young age, and one’s response to it, may be more confusing than trau- matic. But with puberty, the perpetrator’s motivation and perverse manipulation may become experientially clear, and the full horror of the earlier events is retraumatiz- ing. Similarly, with maturity, the nonabusing parent, formerly forgiven with lame rationalizations, may be seen more clearly to have been grossly negligent and even complicit in the abuse. Both objective severity (ranging from relatively mild to torturous) and impact can differ markedly. Reexperiencing includes flashbacks, nightmares, and intrusive memories, but also responses to triggers. Numbing has extended beyond amnesia and emotional numbing to negative beliefs and expectations, as well as to anhedonia and other negative emotions (fear, horror, anger, guilt, shame). Arousal (exaggerated star- tle, hypervigilance) is now extended to anger and irritability, reckless behavior, and so on. Dis- sociative amnesia and emotional blunting are best viewed as effects of strong dis- sociative defenses. The offending trauma is successfully removed from memory, and its accompanying affect is erased. The amnesia and blunting are often stronger than necessary, such that many good memories and feelings are dissociated together with the traumatic memories and emotions, leaving sufferers emotionally blunted and with little sense of their own history. Dissociative flashbacks and other intrusions are best interpreted as effects of periodic weakening of dissociative defenses. The dissociated good memories and feelings may likewise be liberated during such flashbacks, but are generally overshadowed by the trauma and dysphoria, to which the person attempts to respond by dissociating the material once again. Full hallucinatory reliving pro- vides its own “narrative context,” whereas an isolated visual, auditory, tactile, olfac- tory, gustatory, or affective flashback may be misinterpreted as either a hallucination indicative of psychosis or a conversion symptom. Isolated affective flashbacks (experi- enced as affective intrusions of fear, sadness, revulsion, etc. This further complicates the negative crite- rion D symptoms by increasing social isolation and defensive withdrawal, or specific trigger-focused phobias. A patient with a spider phobia, after some years of therapy, worked through a childhood trauma that began in an outhouse. She was sitting in the dark; the door opened; a man stood there, legs apart, arms up and to either side, a black outline of his central body with appendages against the daytime sky. Once she had worked through the trauma, the spider phobia resolved (as did several other symptoms connected to the rape). Other strategies to prevent or blunt flashbacks are chemical—the use of alcohol and other intoxicants. These responses explain the high prevalence of comorbid substance-related disorders. Trauma has been described by memoirists and clinicians alike as time-distorting, causing time to stand still and to conflate. In the traumatized mind, the past event can overtake the present when a post- traumatic response is evoked by a strong enough trigger (something internal or exter- nal to the individual that serves as a reminder of what took place). Victims describe feeling helpless and out of control, at the mercy of outside forces; overwhelmed and disoriented; wrenched from their normal way of being in the world, and losing a sense of ongoing security; challenged to make sense of what happened to them; overcome by loss and grief; terrified; and fearful of injury and death. Many cope through the use of dissociation at the time of the trauma or utilize it in the aftermath to split and avoid painful reminders of the experience. Attempts to master the traumatic experiences, usually Symptom Patterns: The Subjective Experience—S Axis 187 unconscious, are common, and involve reenactments, repetition compulsions, and revictimization. Psychodynamic formulations have emphasized the shock, helplessness, vulner- ability, and terror specific to trauma. Traumatic experience may overwhelm men- tal functioning; interrupt initiative; disturb affective experience, identification, and expression; and interfere with the capacity for symbolization and fantasy. In these ways, it challenges the individual’s meaning, personal relevance, and vocation in life. Trauma-related memories and fantasies are more difficult to work through, as psychic trauma alters the sense of self and of the familiar, as well as the quality of interper- sonal relationships. Clinical literature from the time of Freud and Janet has highlighted persistent reexperiencing and repetition of traumatic events through recurring nightmares/flash- backs/reminiscences, as well as through unconsciously or dissociatively driven reen- actments of traumatic themes—sometimes in psychotherapy, where it is an important source of information leading to understanding of what the individual is struggling with. The importance of the individual meaning of traumatic experience and the fact that trauma may constitute a psychic organizer of sorts have also received emphasis, in the psychodynamic literature and more generally, as shifts in personal assumptions and meaning making. Affective States Affective states include both unmanageably overwhelming feeling reactions expressed in explosions of affect, on the one hand, and their dissociation (numbing) on the other, manifest especially in affective detachment (emotional numbness, blankness, apathy, dissociation of disturbing feelings from the events that gave rise to them) and somatic states (sensory numbness, depersonalization, derealization). Horowitz (1997) and Herman (1992), among others, have identified a host of subjective emotions that accompany severe psychic trauma: •• Fear/terror that the trauma will be repeated; fear of identification with the per- petrator and of becoming similarly destructive; fear of identifying with victims and of defining oneself as a victim. This alternation causes constant shift- ing in one’s perception of reality, which can lead to “realistic” paranoia. The thinking of traumatized individuals is variably affected by the kind of trauma suffered (see above) and the prior personal history, against the background of constitutional tem- perament. Thought content may be dominated by convictions of having been betrayed (especially following interpersonal trauma, betrayal trauma, institutional betrayal, and related secondary injury) or by defensively wishful convictions of the benevolence of abusers or failed protectors (trauma accommodation). There may be the inability to think about the trauma, or an uncompromising avoidance of thinking or talking about the trauma. There may be either total amnesia for the trauma or partial amnesia for certain components of the trauma. This amnesia typically alternates with hypermnesia, rumi- nating about nothing but the trauma, and formulating theories about how one could have avoided the trauma (omen formation). Flashbacks may blur past and present, leading to transient disorientation to time and place. Beliefs may develop to counteract the terrifying experience of helplessness: What one did, what one failed to do, and/or something that one fantasized that led to the trauma, concretely or magically—with the concomitant price of relentless self-criticism and the compulsive urge to punish or avenge oneself. There may be a loss of, or substantial interference with, the capaci- ties for ongoing autobiographical as well as traumatic memory, compromising self- reflection, problem solving, and intentional action. The broad compromising of critical ego functions, sense of reality, judgment, defense, and organization/integration of memory may lead to disorders of the self. There tends to be a decreased ability to integrate experiences, as well as a discontinuity of self and personal experience. Damage to ego functions varies, depending on both the prior stability of specific functions and the patient’s particular defenses (flexible or rigid, adaptive or maladaptive). Somatic States Somatic states characteristic of posttraumatic disorders (also frequently found in other anxiety conditions) include irritability, physiological hyperarousal, sleep disturbances, nightmares, and efforts at self-medication through substance abuse or behavioral or process addictions (food, sex, shopping, workaholism, self-injury). Psychosomatic complaints are frequent, with some traumatized individuals reexperiencing physical states and reactions that occurred in conjunction with the trauma (partial tactile post- traumatic flashbacks). For example, a woman forced to perform fellatio as part of sexual abuse may feel strong sensations of choking or nausea, which she may or may not connect to the childhood experience; or the reactions may be connected more concretely to eating meat, leading to posttraumatic vegetarianism. A growing body Symptom Patterns: The Subjective Experience—S Axis 189 of research suggests the previous lack of recognition of the role of trauma (especially childhood trauma) in later physical illness and somatic response. Relationship Patterns Relationship patterns may include changes in relating to others based on decreased trust and increased insecurity, and/or on states of numbness, alienation, fearfulness, withdrawal, chronic rage, and guilt. Traumatized individuals who are highly shamed may fear rejection or keep themselves away from others for fear of contaminating them. The reality-shifting alternations between reex- periencing and numbing can also lead to guardedness around others based on alien- ation and mistrust and to associated difficulty in developing intimate relationships with trustworthy others. Dissociation, substance abuse, and other consequences of trauma may be helpful in the short term, but over the longer term significantly inter- fere with relationships and the ability to be intimate with others. Working through implies accepting rather than trying to ward off the trauma, approaching rather than avoiding trauma memories, and facing the intolerable.