By H. Ben. State University of New York at Binghamton.
Unfortunately discount tadalis sx 20mg line, these patients had also received a preoperative dose of sustained release oxycodone order cheap tadalis sx on line, which likewise put them at an increased risk for postoperative respiratory depression buy tadalis sx online from canada. In another placebo-controlled crossover study buy 20mg tadalis sx fast delivery, the effects of pregabalin and remifentanil, alone and in combination, on analgesia, ventilation, and cognitive function were examined. The authors concluded that the53 combination of the two drugs produced additive analgesia but potentiated respiratory depression and produced greater cognitive side effects. Prudence therefore dictates that great care should be taken when dosing gabapentinoids in combination with opioids. In the opioid-naive patient, the preoperative dose of gabapentin should rarely exceed 300 mg orally. In addition, gabapentinoids should not be combined with a preoperative dose of sustained release opioid. Only in rare circumstances, such as in the opioid-dependent patient or in the patient at increased risk for chronic postsurgical pain (e. This binding appears to modulate the function and traffic of these channels, which appear on the synaptic bulb of presynaptic neurons. Calcium influx through these channels after a pain-evoked action potential is believed to trigger the fusion of synaptic vesicles with the neuronal membrane and consequent release of neurotransmitters in the dorsal horn of the spinal cord. Gabapentin may exert its analgesic effect by inhibiting or modulating this process. In addition, gabapentin may exert an analgesic effect by activating descending inhibitory noradrenergic pathways that regulate neurotransmission of pain signals in the dorsal horn of the spinal cord. Perioperative gabapentinoids: choice of agent, dose, timing, and effects on chronic postsurgical pain. However, because it takes gabapentin and pregabalin 4 to 6 hours and 8 hours, respectively, to reach peak cerebrospinal fluid levels dosing of the drug the evening prior to surgery may ultimately prove to be the most beneficial method of administration. Unfortunately, side effects such as dizziness, sedation, and49 confusion may preclude this approach. The postoperative dosing of the gabapentinoid may therefore be titrated based on side effects, with larger doses being prescribed during the evening. Dosing should be adjusted accordingly based on the patient’s age, weight, and comorbidities (e. The ideal gabapentinoid dosing regimen that can optimize 3959 immediate postoperative pain and minimize the risk of postoperative respiratory depression, while reducing the development of chronic postsurgical pain, has yet to be elucidated and merits further investigation. Following intravenous administration, the local anesthetic lidocaine has been shown to be analgesic, antihyperalgesic, and anti-inflammatory. The perioperative infusion of56 lidocaine has been shown to not only improve postoperative analgesia in patients recovering from laparoscopic colectomy but also decrease postoperative opioid requirements, attenuate postoperative ileus, and accelerate time to discharge from the hospital. These recommendations result in56 serum concentrations in the therapeutic range, which is considered to be 1 to 5 μg/mL. Serum concentrations greater than 5 μg/mL are associated with cardiovascular and central nervous system toxicity. Lidocaine infusion is contraindicated in any patient with arrhythmia, heart failure, coronary artery disease, Stokes–Adams disease (cardiovascular syncope) and heart block. Future studies are warranted that will identify surgical indications and ideal dosing regimens that are both safe and efficacious. Recent meta-analyses indicate that the perioperative administration of intravenous magnesium may also be an effective adjunct in the treatment of perioperative pain. In a recent trial of 50 patients undergoing scoliosis surgery, the combination of intraoperative intravenous magnesium (bolus dose: 50 mg/kg over 30 minutes, maintenance dose: 8 mg/kg/hr) with low-dose ketamine (bolus dose: 0. The glucocorticoids are well known for their analgesic, anti-inflammatory, and antiemetic effects. The mechanism of the 3960 antiemetic effect of the corticosteroids is less clearly understood but appears to be centrally mediated. Because the drug has been reported to cause perineal irritation in 50% to 70% of individuals following rapid administration, prudence dictates that the drug be diluted in 50 mL of normal saline and injected over 10 minutes prior to surgery. In the opioid-tolerant patient, acute perioperative pain61 management can be challenging, and high dose intravenous dexamethasone, combined with a proton pump inhibitor, has been recommended as a useful therapeutic option. Dexamethasone has also been administered via the62 perineural route as part of a four-drug cocktail. In the United States, the most commonly used drugs are64 morphine, hydromorphone, and fentanyl. Hydromorphone is recommended as an alternative in renal failure; however, fentanyl might be a better choice as it has no active metabolites. The authors do not recommend a background infusion of opioid in the opioid-naive patient. Opioid-related side effects include nausea and vomiting, pruritus, sedation, and confusion. Consensus guidelines for the treatment of nausea and vomiting include prescribing various combinations of dopamine antagonists, serotonin antagonists, and glucocorticoids. Pruritus can be ameliorated with the66 use of diphenhydramine, hydroxyzine, or a low dose of an opioid antagonist (e. Excessive sedation may respond to a change in the opioid; however, use of a multimodal analgesic technique, which incorporates the use of a regional anesthetic (e. Table 55-16 Relative Risk Factors Associated with the Use of Patient-controlled Analgesia Neuraxial Analgesia Although opioid analgesics have been prescribed to patients for many centuries, the exact mechanism of action was not completely understood until 1971, when the opioid receptor was discovered. Within 5 years’ time, Yaksh reported that morphine could produce spinally mediated analgesia in a rat 3962 model. Soon thereafter, in 1979 and 1981, respectively, Wang and then Onofrio reported significant pain relief following the neuraxial administration of morphine in patients with severe cancer-related pain. Since these discoveries, the intrathecal administration of opioids and the epidural administration of opioids plus a local anesthetic has produced significant comfort for our patients. Epidural analgesia is a critical component of multimodal perioperative pain management and improved patient outcome. Meta-analysis investigating the efficacy of epidural analgesia found epidural analgesia to be superior to systemically administered opioids. The efficacy of an epidural67 technique is determined by numerous factors that can include (1) catheter incision site congruency, (2) choice of analgesic drugs, (3) rates of infusion, (4) duration of epidural analgesia, and (5) type of pain assessment (rest versus dynamic). Ideally, the epidural catheter is positioned congruent with the surgical incision (Fig. Thoracic epidural catheter placement is recommended for both thoracic and upper abdominal surgical procedures because of the observed improvement in coronary artery blood flow, attenuation of pulmonary complications, and the reduction in the duration of postoperative ileus. Combining a local anesthetic plus an opioid in the epidural space is believed to have a synergistic effect. The optimal duration67 of epidural analgesia has not been determined, but recommendations are that the infusion be continued for at least 2 to 4 days. Other than analgesia, epidural infusions lasting less than 24 hours do not appear to offer any clear cardiovascular advantages. Epidurally administered opioids have the distinct advantage of producing analgesia without causing significant sympatholytic effect or motor blockade. Analgesia occurs by way of a spinal mechanism and through a supraspinal mechanism following systemic adsorption. The spinal mechanism occurs following diffusion of the drug into the spinal fluid, and is determined by meningeal permeability. In general, the epidural administration of hydrophilic opioids tends to have a slow onset, long duration, and a mechanism of action that is primarily spinal in nature. The epidural administration of lipophilic opioids, on the other hand, has a quick onset, short duration, and a mechanism of action that is primarily supraspinal, secondary to rapid systemic uptake. However, the data are controversial and the site of action of lipophilic opioids such as 3963 fentanyl may primarily be determined by the mode of administration. Bolus administration of fentanyl appears to have a segmental analgesic effect whereas epidural infusion of fentanyl appears to have a nonsegmental (systemic) effect. There are some data, however, that suggest that there can be significant spinal mechanisms of action of the lipophilic opioids, particularly with the thoracic epidural infusion of fentanyl. In the opioid- tolerant patient taking more than 250 mg/day of oral morphine, sufentanil may be considered to be the epidural opioid of choice because of its high intrinsic activity. As previously mentioned, local anesthetic–opioid combinations are the most common form of epidural infusion because the combination is considered to be synergistic. Local anesthetics have the unique ability to block the stress response by blocking afferent input to the spinal cord. Although bupivacaine plus fentanyl may be the most common combination, bupivacaine plus morphine makes more sense from a bioavailability point of view.
With permission of Oxford University Press) erative anatomical assessment of the coronary bed  generic tadalis sx 20 mg without prescription. Speciﬁc guidelines are needed to clearly deﬁne the appropriate situations in which this modality should be used purchase discount tadalis sx online. A major factor associated with in-hos- pital mortality is Staphylococcus aureus infection  discount tadalis sx uk, as the in-hospital mortality rate was particularly high (36%) in the case of Staphylococcus aureus buy tadalis sx, followed by coagulase-negative Staphylococcus spp. Patients with complicated prosthetic valve endo- carditis (new or changing heart murmur, new or worsening heart failure, new or progressive cardiac conduction abnormalities, or prolonged fever during therapy) had a higher mortality than patients with uncomplicated infection (Odds Ratio: 6. Ten-year survival has been reported at 28% in medically man- aged patients compared with 58% in surgically managed patients (p=0. The only predictor of all-cause mortality in this report was the presence of chronic kidney disease (hazard ratio: 3. However, most patients do not undergo valve intervention, resulting in high in-hospital and 1-year follow-up mortality rates . However, the results of a another recent pooled analysis of data from the literature suggest that this condition 13 Prosthetic Valve Endocarditis 181 is not inevitably fatal in these fragile patients and that aggressive treatment may be justiﬁed by a 6-month survival of 60 % [48 ]. In addition, a selection bias in favour of surgery is frequently observed, as some patients are denied surgery despite a surgi- cal indication due to their comorbidities or the presence of septic shock . In addition, a minimal follow-up of 188 days is required to ﬁnd an overall survival advantage of early surgery . It is noteworthy that the decision to operate should be based on a consensus from a heart team involving cardiologists, infectiologists and surgeons. The main objectives of surgery are to control infection by debride- ment with removal of infected and necrotic tissue and reconstruction of cardiac morphology including replacement of the prosthesis. However, some authors con- sider that the beneﬁt of homograft surgery is related more to the surgeon’s ability to extirpate all infected tissues than to the type of valve used for replacement [54 ], as Avierinos et al found that in-hospital mortality, ten-year survival and risk of recur- rence were not inﬂuenced by the type of prosthesis implanted (homograft vs con- ventional prosthesis) . However, an advantage of homograft tissue is that it can be potentially extended into the distal ascending and transverse aortic arch when necessary . The treatment of fungal endocarditis consists of valve replacement associated with intravenous amphoteri- cin B and azole. For mechanical prostheses, vitamin K antagonists should be stopped and replaced by heparin until the need for invasive procedures and neurological complications appears unlikely . Preeminence of Staphylococcus aureus in infec- tive endocarditis: a 1-year population-based survey. Incidence and clinical impact of infective endocarditis after transcatheter aortic valve implantation. Infective endocarditis after trans- catheter aortic valve implantation: results from a large multicenter registry. Is the Bentall procedure for ascending aorta or aortic valve replacement the best approach for long-term event-free survival? The David procedure in different valve patholo- gies: a single-center experience in 236 patients. Late outcomes of mitral valve repair for mitral regurgitation due to degenerative disease. Active infective prosthetic endocarditis after percutaneous edge-to-edge mitral valve repair. Severe infective endocarditis after MitraClip implanta- tion treated by cardiac surgery. Deﬁnition, clinical proﬁle, microbiological spectrum, and prognostic factors of early-onset prosthetic valve endocarditis. Coagulase-negative staphylococcal prosthetic valve endocar- ditis – a contemporary update based on the International Collaboration on Endocarditis: pro- spective cohort study. Relevance of clinical presentation and period of diagnosis in prosthetic valve endocarditis. Investigation of blood culture-negative early prosthetic valve endocarditis reveals high prevalence of fungi. Enterococcal prosthetic valve infective endocar- ditis: report of 45 episodes from the International Collaboration on Endocarditis-merged data- base. Periannular complications in infective endocarditis involving prosthetic aortic valves. Suggested modiﬁcations to the Duke criteria for the clinical diagnosis of native valve and prosthetic valve endocarditis: analysis of 118 pathologically proven cases. Value of transesophageal echocardiography as an adjunct to transthoracic echocardiography in evaluation of native and prosthetic valve endocar- ditis. Evaluation of the Duke criteria in 93 episodes of prosthetic valve endocarditis: could sensitivity be improved? Early diagnosis of abscess in aortic bioprosthetic valve by 18F-ﬂuorodeoxyglucose positron emission tomography-computed tomography. Positron emission tomography/computed tomography for diagnosis of prosthetic valve endocarditis: increased valvular 18F-ﬂuorodeoxyglucose uptake as a novel major criterion. Cardiac computed tomography angiography results in diagnostic and therapeutic change in prosthetic heart valve endocarditis. Multislice computed tomography in infective endocarditis: comparison with transesophageal echocardiography and intraoperative ﬁndings. The use and effect of surgical therapy for prosthetic valve infective endocarditis: a propensity analysis of a multicenter, international cohort. Prognostic factors of overall survival in a series of 122 cases and consequences for treat- ment decision. Staphylococcus aureus prosthetic valve endocarditis: optimal management and risk factors for death. Prosthetic valve endocarditis: early and late outcome following medical or surgical treatment. Surgical treatment for active infective prosthetic valve endocarditis: 22-year single-centre experience. Composite aortic root replace- ment for complex prosthetic valve endocarditis: initial clinical results and long-term follow-up of high-risk patients. Prosthetic endocarditis after transcatheter aortic valve implantation: pooled individual patient outcome. In-hospital and 1-year mortality in patients undergoing early surgery for prosthetic valve endocarditis. Impact of early valve surgery on outcome of Staphylococcus aureus prosthetic valve infective endocarditis: analysis in the International Collaboration of Endocarditis-Prospective Cohort study. The impact of valve surgery on short- and long-term mor- tality in left-sided infective endocarditis: do differences in methodological approaches explain previous conﬂicting results? Medical versus surgical management of Staphylococcus aureus prosthetic valve endocarditis. Treatment of complicated prosthetic aortic valve endocarditis with annular abscess formation by homograft aortic root replacement. Surgical treatment of active aortic endocarditis: homografts are not the cornerstone of outcome. Homograft use in reoperative aortic root and proximal aortic surgery for endocarditis: a 12-year experience in high-risk patients. Ross operation for active culture-positive aortic valve endocarditis with extensive paravalvular involvement. Candida infective endocarditis: an observational cohort study with a focus on therapy. Antithrombotic and thrombolytic therapy for valvular disease: antithrombotic therapy and prevention of thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines. Data from the National Hospital Discharge Survey show that between 1996 and 2003, there was a 49 % rise in the number of new cardiac devices being implanted in the United States. It was also noted that the rate of device infections was two-fold higher in the African American population in com- parison to Caucasians. It may be partly due to aging population and frequent comorbid conditions in the device recipients. Moreover, as patients receiving device therapy are living longer, they are more likely to undergo device exchanges or develop infections. Infections are more common during revision procedures than primary device implantation .
They found no differences among the groups in the time taken to insert these lung isolation devices or in the quality of the lung collapse order tadalis sx 20mg without prescription. The grading was done by the97 operating surgeons who were blinded as to which device was used purchase 20 mg tadalis sx free shipping. It is important order 20mg tadalis sx with amex, however purchase tadalis sx with visa, that the clinician does not limit his/her practice to the use of only one device but rather be versatile and comfortable in the use of several. The anesthesiologist should become familiar with the various devices used to achieve lung separation. Bronchial blockers can be safely and effectively used either for simple procedures such as a brief wedge resections or for more complexes extended procedure such as lobectomy or pneumonectomy. In these cases, when planning to provide lung separation, the postoperative period should be considered and the appropriate tube placed. Many procedures that are not considered to represent absolute indications for lung separation are lengthy and complex. Complex lung resection, with or without chest wall resection, thoracoabdominal esophagogastrectomy, thoracic aortic aneurysm resection with or without total circulatory arrest, or an extensive vertebral tumor resection, may result in facial edema, secretion, and hemoptysis, requiring postoperative ventilatory support. Other indications for postoperative ventilatory support are marginal respiratory reserve, unexpected blood loss or fluid shift, hypothermia, and inadequate reversal of residual neuromuscular blockade. In addition, it is more difficult to suction through the lumens, and a longer, narrower suction catheter is needed to reach the tip of the endobronchial lumen. Alternatively, the tube exchange may be performed under direct vision using one of several commercially available video laryngoscopes, such as the GlideScope (Verathon Medical), C-Mac (Karl Storz), or the Mc Grath (Aircraft Medical) (see Chapter 28). In addition, one should always plan in advance for the 2601 postoperative period when selecting the method of lung separation. Finally, in these cases, a close dialog with the surgical team is of vital importance. It is a common practice to visualize the tip of the blue bronchial cuff at the level of the carina to ensure that the left upper lobe orifice is not obstructed. High oxygen concentration serves to protect against hypoxemia during the procedure and provides a higher margin of safety. Some clinicians use an O 80%/N O 20% mixture as long that2 2 the SpO is maintained in a safe range. Tidal volumes (V ) ranging between 8 and 15T T mL/kg produced no significant effect on transpulmonary shunt or PaO. A V greater than 15 mL/kg may recruitT the atelectatic alveoli in the dependent lung. Retrospective clinical studies, however, suggest that the use of large V favors the development of lung injury in theseT patients. In this study, neither time course nor concentrations of2 pulmonary or systemic inflammatory mediators (cytokines) differed between the two ventilatory settings within 3 hours. In one study of patients undergoing pneumonectomy, 18% developed postoperative respiratory failure. The patients who developed respiratory failure had been ventilated with larger intraoperative V than those who did not (median, 8. In patients undergoing general anesthesia, lung recruitment maneuvers proved to be easy to perform and effective in reversing alveolar collapse, hypoxemia, and decreased compliance. The beneficial effect of an alveolar recruitment strategy on arterial oxygenation and respiratory compliance in anesthetized patients undergoing nonthoracic surgery in the supine position has been demonstrated by Tusman et al. It is important to apply the maneuvers over several minutes with a pressure of at least 20 cm H O and a peak of 40 cm H O. Because hypocarbia can only be achieved by hyperventilating the dependent lung, it raises the mean intra- alveolar pressure and therefore increases the vascular resistance in that lung. No severe adverse effects2 2 were reported in relation to the therapeutic hypercarbia. If this increase in resistance is limited to the dependent lung, blood flow can be diverted only to the nondependent (nonventilated) lung, increasing shunt fraction and further decreasing PaO2. Insufflation of oxygen without maintaining a positive pressure failed to improve PaO2. Intermittent reinflation of the collapsed (nondependent) lung with oxygen also resulted in a significant improvement in PaO. In addition, it is difficult to place the stapler on a lung that is not completely collapsed, and there is an increase in incidence of postoperative air leak. At this2 pressure, the lung becomes overdistended, which interferes with surgical exposure. The catheter to the nondependent lung is usually insufflated with 5 L/min of oxygen using a modified Ayre’s T- piece (pediatric) circuit, and the valve on the expiratory limb is adjusted to the desired pressure as read on the attached gauge. This is2 2 usually monitored indirectly with the use of a capnometer or other multigas analyzer. Frequent monitoring of arterial blood gases and use of a pulse oximeter continue throughout the operative period. It is also essential to work closely with the surgeon in case reinsufflation of the lung is necessary. Also, depending on the stage of surgical dissection, if a pneumonectomy is being performed, ligation of the pulmonary artery eliminates the shunt. A sudden increase in peak airway pressure may be secondary to tube dislocation because of surgical manipulation, resulting in impaired ventilation. In addition, the ability to auscultate by a stethoscope over the dependent lung is extremely important. If there is any doubt about the stability of the patient, or if the patient becomes hypotensive, dusky, or tachycardic, two-lung ventilation should be resumed until the problem has been resolved. Because of pericardial manipulation (during left thoracotomy in particular) and pulling on the great vessels, cardiac dysrhythmias and hypotension are not uncommon. Cardiotonic drugs should be prepared and kept available for use during any thoracic surgical procedure. They should be applied with a sustained peak pressure of 40 cm H O to be effective. Fluid administration during the2 procedure must be limited to avoid fluid overload that could increase pulmonary capillary permeability. Thoracic surgical patients are more likely than others to have increased airway reactivity and a propensity to develop bronchoconstriction. The potent inhaled anesthetic agents have all been shown to decrease airway reactivity and bronchoconstriction provoked by hypocapnia or inhaled or irritant aerosols. Their mechanism of action is probably a direct one on the airway musculature itself, and potent inhaled anesthetic agents are therefore the drugs of choice in patients with reactive airways. For an inhalation induction, halothane or sevoflurane might be preferable because they are the least pungent of the three drugs, although once the patient is asleep, isoflurane may be the preferred drug because it raises the cardiac dysrhythmia threshold and provides greater cardiovascular stability than halothane (see Chapter 18). Fentanyl does not appear to influence bronchomotor tone, but morphine may increase tone by a central vagotonic effect and by releasing histamine. In most patients, anesthesia is safely induced with propofol or etomidate (since thiopental is no longer available in the United States). In patients with reactive airways, ketamine may be the drug of choice for induction because it has a bronchodilator effect and has been successfully used in the treatment of asthma. However, propofol was associated with a reduction in cardiac index and right ventricular ejection fraction. Studies have shown that ventilation with increased V and pressures can produce a proinflammatoryT reaction (e. Compared with propofol there 2611 was a significant reduction in inflammatory mediators and a significantly better clinical outcome defined by postoperative adverse events with sevoflurane. In this respect, pancuronium, vecuronium, rocuronium, and cisatracurium probably represent the drugs of choice. Succinylcholine is useful to provide rapid profound relaxation for intubation of the trachea and is not associated with an increase in airway reactivity. Atropine or glycopyrrolate may be used to block the muscarinic effects of acetylcholine and thereby protect against cholinergically induced bronchoconstriction. They concluded that the increased pressure during hypoxia was caused by a direct effect on the pulmonary vessels. Whereas they delivered hypoxic gas mixtures to both lungs, others have studied the effects of the size of the hypoxic segment and the size of the hypoxic stimulus on perfusion pressure and on flow diversion. Flow diversion, as a percentage of flow to the test segment under normoxic conditions, decreased with increasing size of the hypoxic test segment from a maximum of 75% for very small segments to zero when the whole lung was made hypoxic. Flow diversion increased linearly as PaO2 was decreased over the range of 128 to 28 mmHg.
The taboo of cardiac surgery was summarized by Theodore Billroth when he supposedly said “any surgeon who would attempt an operation on the heart should lose the respect of his colleagues purchase genuine tadalis sx on-line. Fortunately cheap tadalis sx 20mg without a prescription, the turn of the 20th century saw many advances in anesthesia practice order tadalis sx in united states online, blood typing and transfusion cheap 20mg tadalis sx visa, anticoagulation, and antibiosis as well as surgical instrumentation and technique. Some continued to attempt procedures like closed mitral valvotomy in the midst of these technologic advancements, but outcomes were still very poor with mortality rates exceeding 80%. Many believe that the successful ligation of a 7-year-old girl’s patent ductus arteriosus by Robert Gross in 1938 served as the landmark case for modern cardiac surgery. Soon after Gross’ achievement, a host of new procedures were developed for repairing congenital cardiac lesions, including the first Blalock–Taussig shunt performed on a 15-month-old “blue baby” in 1944. Although the shunt had been successfully demonstrated in animal68 models, Austin Lamont, Chief of Anesthesia at Johns Hopkins, was not supportive of the procedure. He emphatically stated “I will not put that child to death” and left the open drop ether–oxygen anesthetic to resident anesthesiologist Merel Harmel. Together, Harmel and Lamont116 would publish the first article on anesthesia for cardiac surgery in 1946 based on 100 cases with Alfred Blalock and repair of congenital pulmonic stenosis. Closed cardiac surgery ensued, and anesthesia pioneers like William McQuiston and Kenneth Keown worked side by side with surgeons during procedures like the first aortic–pulmonary anastomosis and the first transmyocardial mitral commissurotomy. Never before had anesthesia providers worked as intimately with surgeons for the patient’s welfare. The first successful use of Gibbon’s 98 cardiopulmonary bypass machine in humans in May 1953 was a monumental advance in the surgical treatment of complex cardiac pathology that stimulated international interest in open heart surgery and the specialty of cardiac anesthesia. Over the next decade, rapid growth and expanded applications of cardiac surgery, including artificial valves and coronary artery bypass grafting, required many more anesthesiologists acquainted with these specialized techniques. Earl Wynands published one of the first articles on anesthetic management of patients undergoing surgery for coronary artery disease. As cardiac surgery evolved, so did the perioperative monitoring and care of patients undergoing cardiac surgery. Postoperative mechanical ventilation and surgical intensive care units appeared by the late 1960s. Devices like the left atrial pressure monitor and the intra-aortic balloon pump offered new methods of understanding cardiopulmonary physiology and treating postoperative ventricular failure. At Texas Heart Institute, Stephen Slogoff and Arthur Keats demonstrated the negative impact of myocardial ischemia on clinical outcome. By the end of the 1980s, the same duo would reveal that the choice of anesthetic agent had little impact on outcome, challenging the earlier paradigm of “isoflurane steal” proposed by Sebastian Reiz. Developments like cold potassium cardioplegia, monitoring and reversal of heparin, and reduction of blood loss with aprotinin would change the practice of cardiac anesthesia. Transesophageal echocardiography, introduced into cardiac surgery by Roizen, Cahalan, and Kremer in the 1980s, helped to further define the subspecialty of cardiac anesthesia. Neuroanesthesia Brain surgery is considered by some to be the oldest of the practiced medical arts. Prehistoric brain surgery was also practiced by civilizations in South America, Africa, and Asia. Macewen, well known for introducing the technique of orotracheal intubation, promoted the idea of teaching medical students at Glasgow Royal Infirmary the art of chloroform anesthesia. Like Macewen, Sir Victor Horsely was a neurosurgeon with an interest in anesthesia. His experiments of how ether, chloroform, and morphine affected intracranial contents led him to conclude that “the agent of choice was chloroform and that morphine had some value because of its cerebral constriction effects. Meanwhile, Harvard medical student and aspiring neurosurgeon Harvey Cushing developed the first charts to record heart rate, temperature, and respiration during anesthesia. Cushing was one of the first surgeons to recognize the importance of dedicated, specially trained anesthesia personnel versed in neurosurgery. Charles Frazier,121 a neurosurgical contemporary of Cushing, also recognized this need, stating that “no [cranial] operation be undertaken unless the services of a skilled anesthetizer are available. Part of the motivation driving this change was the increased duration in surgical time. Cushing and colleagues used a “slow” surgical technique for most surgical procedures, where the average duration for cranial operations was 5 hours. Therefore, prolonged patient exposure to chloroform or ether anesthesia was likely to result in increased bleeding, postoperative headache, confusion, and/or vomiting. Cushing and his contemporaries thought the use of local or regional anesthesia lessened the risk of these complications. After a decade, it was realized that the remote positioning of the anesthetist was troublesome when managing the airway of an awake or lightly sedated patient undergoing cranial surgery with regional anesthesia. Also, endotracheal tubes, although introduced at the beginning of the century, had become popular instruments for securing a patient’s airway and providing inhalation anesthesia. Combined, these circumstances led to the rapid resurgence of popularity in general anesthesia for cranial surgery, a trend that would continue to the present day. Although the introduction of agents like thiopental, curare, and halothane advanced the practice of anesthesiology in general, the development of methods to measure brain electrical activity, cerebral blood flow, and 100 metabolic rate by Kety and Schmidt and intracranial pressure by Lundburg “put neuroanesthesia practice on a scientific foundation and opened doors to neuroanesthesia research. Many lessons learned during this period of groundbreaking research are still commonly used in modern neuroanesthesia practice. Obstetric Anesthesia Social attitudes about pain associated with childbirth began to change in the 1860s, and women started demanding anesthesia for childbirth. Societal pressures were so great that physicians, although unconvinced of the benefits of analgesia, felt obligated to offer this service to their obstetric patients. This method gained popularity after German obstetricians Carl Gauss and Bernhardt Krönig widely publicized the technique. Numerous advertisements touted the benefits of Twilight Sleep (analgesia, partial pain relief, and amnesia) as compared to ether and chloroform, which resulted in total unconsciousness. Because of the effects of scopolamine, many patients became disoriented and would scream and thrash about during labor and delivery. Gauss believed that he could minimize this reaction by decreasing the sensory input; therefore, he would put patients in a dark room, cover their eyes with gauze, and insert oil- soaked cotton into their ears. The patients were often confined to a padded bed and restrained with leather straps during the delivery. Virginia Apgar’s landmark 1953 publication of a system for evaluating newborns (the Apgar Score) helped to demonstrate that there actually was a difference in the neonates of mothers who had general versus regional anesthesia. Her physicians claimed her death was not related to complications from the method of Twilight Sleep that was used. However, their benefits were underappreciated for many years because the obstetricians seldom used these techniques. Initially, spinal anesthesia could be administered by inexperienced personnel without monitoring. The combination of inexperienced providers and lack of patient monitoring led to higher rates of morbidity and mortality than those observed for general anesthesia. At the onset of the 21st century, anesthesia-related deaths during cesarean sections under general anesthesia were reported as being more likely than neuraxial anesthesia-related deaths, making regional anesthesia the method of choice. Transfusion Medicine Paleolithic cave drawings found in France depict a bear losing blood from multiple spear wounds, indicating that primitive man understood the simple relationship between blood and life. Denis had learned of Richard Lower’s transfusion of lamb’s blood into a dog the previous year. Lamb’s blood was most frequently used because the donating animal’s essential qualities were thought to be transferred to the recipient. His next two patients were not as fortunate, 102 however, and Denis avoided further attempts. Given the poor outcomes of these early blood transfusions, and heated religious controversy regarding the implications of transferring animal-specific qualities across species, blood transfusion in humans was banned for more than a 100 years in both France and England beginning in 1670. Landsteiner, an Austrian physician, originally organized human blood into three groups based on substances present in the red blood cells. On the basis of these findings, Reuben Ottenberg performed the first type-specific blood transfusion in 1907. Transfusion of physiologic solutions occurred in 1831, independently performed by O’Shaughnessy and Lewins in Great Britain.