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Study objective To describe the adverse events associated with the intraoperative injection of isosulfan blue in a large group of patients having a wide range of surgical procedures, and to identify risk factors for these events. Design Retrospective chart review. Setting University-affiliated institution specializing in malignancies Patients 1835 patients representing a total of 1852 surgical procedures. Measurements Incidence, type, severity, onset time, duration, management, and the presence of potential risk factors for adverse events. Events were considered "major" if potentially life-threatening hypotension occurred. Main results Adverse events occurred in 28 procedures (1.5%) and 14 of these adverse events (0.75%) were classified as major. The types of events were: skin reactions in 21 patients, hypotension in 14 patients, edema in 1 patients, and unspecified in 1 patient. The time of onset for adverse events was 42.2 ± 53.9 minutes (median, 17.5; range, 1 to 180 min) after isosulfan blue injection, and was significantly longer for minor reactions compared with major events (p = 0.015). The longest adverse event lasted at least 21 hours. Treatment was successful with usual antiallergy/antianaphylaxis medications. Ten patients received diphenhydramine alone, and four patients received intravenous epinephrine infusions. Factors associated with a significantly increased incidence of adverse events were isosulfan blue injection in the vulvar area ( p = 0.000038), and the chronic preoperative use of angiotensin-converting enzyme inhibitors or angiotensin receptor-blocking agents ( p = 0.043). Trends toward an increased risk of an adverse event were noted with isosulfan blue injection in the breast area ( p = 0.19), and having more than one surgical procedure with isosulfan blue ( p = 0.14). Conclusions Although the most frequent adverse event associated with injection of isosulfan blue was a skin reaction, potentially life-threatening hypotension occurred in 0.75% of all procedures. Anesthesiologists must be aware of the variable onset time and potentially prolonged duration of the adverse events. They should recognize the need for extra vigilance in patients with potential risk factors, and have the usual antiallergy/antianaphylaxis medications available for administration if necessary.

Traumatic coagulopathy manifests as a hypocoagulable state associated with hypothermia, acidosis, and coagulation factor dilution. The diagnosis must be made clinically because traditional coagulation tests are neither sensitive nor specific and take too long to be used for intraoperative monitoring. We hypothesized that the activated coagulation time (ACT) would reflect the global coagulation status of traumatized patients and would become elevated as coagulation reserves become exhausted. A prospective protocol was used to study 31 victims of major trauma who underwent immediate surgical intervention. Victims of major head trauma were excluded and patients were selected at random over an 8-month period. At least two serial intraoperative blood samples were obtained at 15-min intervals via indwelling arterial catheters. A Hemochron model 801 coagulation monitor was used to measure the ACT. Of the 31 patients studied, 7 became clinically coagulopathic and 24 did not. The ACT measurements of coagulopathic and noncoagulopathic trauma patients were significantly different by multiple statistical comparisons. Both groups differed from normal, nontraumatized patients. The coagulopathic trauma patients had significantly elevated values when compared with other trauma patients or to normal values. We conclude that a low ACT reflects the initial hypercoagulability associated with major trauma and an elevated ACT is an objective indicator that the coagulation system reserve is near exhaustion. An elevated ACT may represent an indication for considering damage control maneuvers or more aggressive resuscitation.

Study objective To examine current practice regarding the performance of tracheal extubation of adult surgical patients while deeply anesthetized (deep extubation). Design and setting Survey comprised of an anonymous written questionnaire mailed to 1,000 randomly selected active American Society of Anesthesiologists members. Measurements and main results Questionnaires were mailed between February and April 1998. Five hundred eighty-three completed forms were returned, 538 of which were suitable for data analysis. Responses from anesthesiologists who infrequently or never administer general anesthetics to adult surgical patients were excluded. The overall frequency of deep extubation of adults was "never" for 106 respondents (19.7%), "rarely" for 87 (16.2%), and "more frequently" for 345 (64.1%). The most common reasons for never performing deep extubations were lack of necessity and concern regarding potential laryngospasm and aspiration. The most frequent indications for deep extubations were unclipped intracranial aneurysm, reactive airway disease, and open-globe eye surgery. The most frequent contraindications to deep extubations for those who otherwise perform the technique were difficult airway, aspiration risk, and obesity. After performing a deep extubation, 44.0% of respondents remain with the patient in the operating room until he or she is awake. Deep extubations were perceived to have no consistent effect on operating room turnover time by 61.6% of anesthesiologists who perform them. Conclusions Most anesthesiologists in this survey perform deep extubations in adult surgical patients. Lack of necessity and potential respiratory complications were the main reasons cited by those who do not use the technique. Future investigations are necessary to examine the risk-to-benefit ratio of the technique in adults. Our results may be used to determine which potential indications should be examined in such studies and to help delineate the standard of care followed in this country.

This prospective, double-blind, randomized trial assessed the effectiveness of high-dose tranexamic acid given in the preoperative period on blood loss in patients undergoing cardiopulmonary bypass. One hundred fifty patients scheduled to undergo cardiac operations with cardiopulmonary bypass were randomized into three groups of equal size. The first group received 10 gm of tranexamic acid intravenously over 20 minutes before sternotomy and a placebo infusion over 5 hours. The second group received 10 gm of tranexamic acid over 20 minutes and then another 10 gm infused intravenously over 5 hours. The control group received a placebo bolus and a placebo infusion over 5 hours (0.9% normal saline solution). The blood loss after the operation was measured at 6 hours and 24 hours. The homologous blood and blood products given during and up to 48 hours after operation were recorded. Eighteen percent of the control group patients shed more than 750 ml blood in 6 hours compared with only 2% in both tranexamic acid groups. Patients who shed more than 750 ml blood required 93% more red blood cell transfusions than patients without excessive bleeding. Tranexamic acid (10 gm) given intravenously in the period before cardiopulmonary bypass reduced blood loss over 6 hours by 50% and over 24 hours by 35%. Continued tranexamic acid infusion (10 gm over 5 hours) did not reduce bleeding further. There was no difference in the coagulation profile before operation between patients with and without excessive bleeding. However, coagulation tests done in the postoperative period indicated ongoing fibrinolysis and platelet dysfunction in patients with excessive bleeding. (J THORAC CARDIOVASC SURG 95;110:835-42)

In this institution, two antifibrinolytic agents have been in routine use before cardiopulmonary bypass (CPB) to prevent bleeding due to fibrinolysis; ϵ-aminocaproic acid (EACA) or tranexamic acid (TA) are administered as intravenous infusions over 2 hours, from the time of anesthetic induction until the onset of CPB. TA is 10 times more potent and binds more strongly to plasminogen than EACA. Data were collected retrospectively on 411 patients undergoing first-time coronary artery bypass grafting with cardiopulmonary bypass who had received one of four therapy regimens: 10 g of EACA (65 patients), 15 g of EACA (60 patients), 6 g of TA (100 patients), or 10 g of TA (75 patients). Patients who did not receive any drug (91) served as controls. Anesthestic technique and the heparin/protamine protocol did not differ. Blood collected by mediastinal and pleural tubes was auto transfused up to 6 hours postoperatively. Both TA and EACA reduced post-CPB bleeding in the first 24 hours. Ten grams of TA was the most effective, resulting in a 52% and 36% reduction in blood loss over controls at 6 and 24 hours, respectively. Although 10 g of TA was more effective than 6 g of TA in blood loss control for the first 6 hours, the difference was not significant at 24 hours. A significantly lower number of patients in the 10 g TA group received blood products than in control (28% v 49%) patients (P = 0.02). Pretreatment with 10 g of TA prevented excessive (over 750 mL in 6 hours) bleeding after CPB.

BACKGROUND: Aprotinin has been used to decrease blood loss with complicated cardiac surgery but has not been investigated in extrapleural pneumonectomy, an operation that does not use cardiopulmonary bypass. In this prospective, randomized, placebo-controlled, double-blind trial, the authors investigated whether aprotinin decreased blood loss in patients who underwent this operation. METHODS: After appropriate statistical design and institutional review board approval, eligible patients who were scheduled for extrapleural pneumonectomy were randomized to receive either aprotinin or placebo during the operation. Blood loss and survival data were obtained from electronic medical records and surgical databases. RESULTS: Of 20 patients who were enrolled, 16 patients met criteria for blood loss analysis. Four patients were excluded from the blood loss analysis: Three patients were inoperable because of tumor spread and underwent limited surgery, and 1 patient died intraoperatively because of acute, massive hemorrhage. The mean blood loss was 769 mL with aprotinin versus 1832 mL with placebo (P = .05; Wilcoxon test). All 20 patients were included in survival analyses. All 9 patients who received placebo died. In contrast, 7 of 11 patients who received aprotinin remained alive at the time of the current report. Kaplan-Meier survival curves differed significantly between the 2 groups (P = .0004). A Bayesian multivariate survival analysis of 18 patients who had complete data available on 8 prognostic variables indicated a posterior probability of .99 that aprotinin was beneficial. CONCLUSIONS: Aprotinin decreased blood loss. After accounting for covariate effects, there was a significant comparative benefit with aprotinin in postoperative survival. This finding was unexpected and could not be considered conclusive because of the small size of the current study. A confirmatory study may be warranted. Cancer 2009. © 2009 American Cancer Society.

Continuous pulse oximetry was performed on 173 adults after general anaesthesia for elective inpatient surgery, throughout their post-anaesthesia care unit (PACU) stay. Supplemental oxygen was administered for greater than or equal to 30 min after arrival and subsequently discontinued before discharge to the ward. The mean and minimum oxyhaemoglobin saturation (SpO2) after discontinuing oxygen were lower than those values achieved during oxygen administration and preoperatively (P less than 0.001). At least one hypoxaemic episode (SpO2 less than or equal to 90% for greater than or equal to 15 sec) occurred in 70 subjects (41%) and 45 of these had a moderate-severe episode (SpO2 greater than or equal to 90% for less than or equal to 2 min or SpO2 less than or equal to 85%). The hypoxaemic episodes began 20 +/- 20 min (range 1-100; median 15) after discontinuing supplemental oxygen. Cyanosis was detected in only four of the 70 patients who desaturated. Factors associated with hypoxaemia were: ASA physical status class; surgical duration greater than or equal to 90 min; and preoperative mean SpO2 less than 95%. Factors not associated with hypoxaemia were: age, sex, % ideal body weight, smoking history, preoperative minimum SpO2, premedication and type of surgery. In conclusion, after discontinuing supplemental oxygen in the PACU, hypoxaemia was common, difficult to detect clinically, and associated with ASA class, surgical duration and preoperative mean SpO2.

b fi l 1 s g s v f d s w i e w a l d o EDIASTINOSCOPY IS CONSIDERED the “gold standard” for mediastinal staging in lung cancer.1,2 owever, it is an invasive procedure requiring general ansthesia with invasive arterial catheter monitoring and often ostoperative hospitalization. More recently with the develpment of new minimally invasive technology, endobronhial ultrasonography (EBUS) has been reported to be useful n detecting mediastinal and hilar lymphadenopathy. A new inear array ultrasonic bronchoscope (Fig 1) with the ability o perform real-time transbronchial needle aspiration (TBNA) nder direct ultrasound (US) guidance was developed by lympus Corporation (Tokyo, Japan). EBUS has high senitivity and specificity when compared with computed toography or positron-emission tomography imaging for meiastinal staging of patients with potentially resectable lung ancer.3-5 Tissue confirmation obtained by EBUS-TBNA is specially important for accurate staging, for detecting hisologic types of lung malignancy, and for differential diagosis of mediastinal lymphadenopathy.

Antiemetics currently in use are not totally effective. Neurokinin-1 receptor antagonists are a new class of antiemetic that have shown promise for chemotherapy-induced nausea and vomiting. This is the first study evaluating the efficacy and tolerability of the neurokinin-1 receptor antagonist, aprepitant, for the prevention of postoperative nausea and vomiting.In this multicenter, double-blind trial, we randomly assigned 805 patients receiving general anesthesia for open abdominal surgery to a preoperative dose of aprepitant 40 mg orally, aprepitant 125 mg orally, or ondansetron 4 mg IV. Vomiting, nausea, and use of rescue therapy were assessed over 48 h after surgery. Treatments were compared using logistic regression.Incidence rates for the primary end point (complete response [no vomiting and no use of rescue] over 0-24 h after surgery, tested for superiority of aprepitant) were not different across groups (45% with aprepitant 40 mg, 43% with aprepitant 125 mg, and 42% with ondansetron). The incidence of no vomiting (0-24 h) was higher with aprepitant 40 mg (90%) and aprepitant 125 mg (95%) versus ondansetron (74%) (P0.001 for both comparisons), although between-treatment use of rescue and nausea control was not different. Both aprepitant doses also had higher incidences of no vomiting over 0-48 h (P0.001). No statistically significant differences were seen among the side effect profiles of the treatments.Aprepitant was superior to ondansetron for prevention of vomiting in the first 24 and 48 h, but no significant differences were observed between aprepitant and ondansetron for nausea control, use of rescue, or complete response.

Drs Bottle and Sanders present an interesting concept that implies that patients who have surgery on Friday may have a poorer prognosis. Many patient factors are mentioned, including lack of office advice on the weekend and a greater propensity for utilization of emergency rooms. Nevertheless, it could be the perceived need to operate on those patients before their condition deteriorates over the weekend that leads to the poor outcomes – they felt sick enough that surgery should not be delayed until the following Monday’s schedule but actually would have improved without the surgery and its attendant risks. Importantly, there may also be other non-medical ‘‘political’’ factors that may be more accountable. For example, in my observance, the more ‘‘powerful’’ (i.e., in seniority within the hospital/university infrastructure) the individual, the less likely they are to work on Friday. Perhaps the more junior and less accomplished surgeons are relegated to the Friday operating room and on-call slots. Furthermore, the responsible operating surgical faculty member may be more likely to ‘‘flee’’ for the weekend before the surgery is completed, leaving the trainees to finish the operation. This may be true in anesthesia as well. Indeed, I recall being very loosely supervised (i.e., the last faculty member was covering many rooms) at a well-known pediatric hospital as a fourth year resident on a Friday!

Studies of the respiratory effects of perioperative analgesic and anesthetic agents are complicated by evidence that healthy subjects and those with COPD may have abnormalities of oxygenation and ventilation during sleep. This report thus characterizes respiration during sleep preoperatively in a population frequently examined in postoperative analgesia studies. Sixty-two thoracic surgical patients were monitored by continuous respiratory inductive plethysmography, 49 of whom also had continuous pulse oximetry and bi-hourly blood gas measurements. The mean respiratory rate (RR) at each hour during sleep was similar to the awake RR (P > 0.06). The minimum RR during sleep was 7.6 ± 2.1 (2.6–9.8; median 7.9). At least 1 apnea (tidal volume - 15 sec) occurred in 77% of subjects, and 32% had >-1 slow respiratory rate (SRR; 5-min RR -1 desaturation (DESAT90; SpO2 - 15 sec) episode. The pH at hours 2 and 4 was significantly (P 0.02). Interpatient variability was high, especially for episodic abnormalities. The percentage ideal body weight correlated with the number of DESAT90 episodes, and the awake RR correlated with the number of SRR and apneic episodes. Factors associated with minimum SpO2 were age, V25, V50, DCO, awake PaO2 and SpO2 The highest coefficient for any correlation was 0.55. In summary, a high percentage of subjects had >- 1 episode of desaturation, SRR, and/or apnea; no single set of respiratory parameters defined a “typical” thoracic surgical patient. Eight demographic and awake respiratory factors correlated with various respiratory events during sleep, but their predictive value was low.

Background Intermittent self-administered nitrous oxide has long had widespread use as an analgesic in labor, but its efficacy has not been adequately established. Questions about its effect on maternal oxygenation between labor contractions also have been raised. Methods Twenty-six women were recrulted to participate in a randomized, double-blind, cross-over, placebo-controlled study to assess the effect of intermittent nitrous oxide inhalation on labor pain and maternal hemoglobin oxygen saturation (SpO2) during the first stage of labor. Visual analog scale pain scores for each of five consecutive labor contractions were measured after administration of either nitrous oxide or compressed air. Results Mean visual analog scale pain scores for five contractions were 5.1, 5.2, 5.7, 5.2, and 5.6 (nitrous oxide) and 4.9, 5.2, 6.1, 5.6, and 5.7 (compressed air). There were no statistically significant differences in pain when nitrous oxide as compared with compressed air was administered. Pain scores did not differ significantly over time as a function of inhaled substance (F = 0.41, P = 0.53). The mean lowest SpO2 observed between these contractions after self-administration of nitrous oxide and air were 97, 97, 97, 97, and 97% (nitrous oxide) and 97, 96, 96, 96, and 96% (compressed air). SpO2 was significantly higher after nitrous oxide administration (F = 8.8, P = 0.007). Conclusions While intermittent self-administered 50% nitrous oxide in oxygen does not appear to predispose parturient women to hemoglobin oxygen desaturation, its analgesic effect has yet to be clearly demonstrated.

Although they account for less than 1 % of operable congenital cardiac anomalies,' vascular rings are not an uncommon cause of airway obstruction in children . 2 Approximately 5% of vascular rings are caused by an aberrant left pulmonary artery (PA), which originates from the right PA, compresses the trachea and/or right main-stem bronchus as it passes from right to left between the trachea and esophagus, and finally enters the left hilum (Fig 1). This condition is rarely present in adults. A case is presented of an adult who required correction of this congenital abnormality. The anesthetic course was also complicated by other congenital abnormalities that are associated with PA slings.

INTRODUCTION: Aprotinin (TrasylolTM Bayer Corporation, West Haven, CT) is a serine protease inhibitor, which inhibits all serine proteases including plasmin. It has been used to significantly decrease blood loss during repeat cardiac surgery utilizing cardiopulmonary bypass and is currently the only pharmacologic agent approved by the FDA for this purpose. The operation of extrapleural pneumonectomy (EPP), done almost exclusively for mesothelioma, is associated with the potential for significant blood loss due to the large raw surface of the hemithorax left behind after resection of the parietal pleura. We investigated whether aprotinin would decrease blood loss and transfusion requirement in this major operation.

Proper functioning of every item of anesthetic equipment is of utmost importance in ensuring the safety of modern-day anesthesia. Accordingly, guidelines have been developed by several regulatory agencies for the safe manufacturing and use of most equipment used in anesthesia. As well, the Food and Drug Administration (FDA) has developed recommendations to test the integrity of all anesthetic apparatus prior to use (1). However, mishaps due to equipment failure still occur. Here we describe a case of breathing circuit obstruction due to failure to remove the packaging from a CO, absorber canister.

To the Editor: Neuromuscular blockers (NMBs) may be added to intravenous regional anesthesia (IVRA) to enhance both the motor and sensory blockade.1 , 2Most reports indicated lack of systemic effects with these agents but we encountered a case of weakness upon tourniquet deflation with the use of pancuronium despite a tourniquet inflation time of 89 min. A healthy 41-yr-old, 81 kg man presented for repair of a lacerated right extensor pollicis longus tendon and IVRA was performed with 40 lidocaine ml 0.7% plus 2 mg pancuronium. This quantity of pancuronium was inadvertently administered instead of the 1 mg dose typically used at our institution. The block was performed in the standard manner, with exsanguination of the arm and inflation of a double-cuffed tourniquet to 300 mmHg. The tourniquet was deflated after 89 min. Three minutes later the patient experienced diplopia and was unable to lift his head. Intravenous administration of 2.5 mg neostigmine (with 0.5 mg glycopyrrolate) terminated the diplopia and allowed a sustained head lift for > 5 sec. The apparent systemic release of a substantial quantity of NMB in this case is in contrast to that of local anesthetics, in which one would expect no systemic effects after deflation of a tourniquet which had been inflated for 89 min. The differences probably relate to the lesser extremity tissue binding with NMBs due to their greater ionization and lower lipid solubility. Clinicians who add NMBs to IVRA should be aware of the potential for systemic weakness, even after prolonged tourniquet inflation.

A randomized, double-blind, placebo-controlled trial was conducted to assess the analgesic, pharmacokinetic, and clinical respiratory effects of 72-h application of two transdermal fentanyl (TTSF) patch sizes in patients undergoing abdominal hysterectomy.TTSF patches releasing 50 micrograms/h (TTSF-50) or 75 micrograms/h (TTSF-75) fentanyl or placebo patches were applied to 120 women 2 h before abdominal hysterectomy under general anesthesia. Postoperatively, all patients had access to supplemental morphine using patient-controlled analgesia pumps. Each patient was attended continuously by a research nurse for 8 h on the night before surgery and for 84 h after patch application. The following data were collected: visual analog scale pain scores, supplementary analgesia, fentanyl plasma concentration (4-h intervals), continuous hemoglobin saturation (pulse oximetry), respiratory pattern (continuous respiratory inductive plethysmography), and adverse effects (nausea, vomiting, pruritus). Data analysis included analysis of variance, Kruskal-Wallis, and chi-squared. P0.05 was considered significant.There were no demographic differences among groups. Visual analog scale pain scores were significantly lower for the TTSF-75 group, and supplemental morphine was significantly decreased in the TTSF-75 group in the postanesthesia care unit and for both the TTSF-50 and the TTSF-75 group for 8-48 h postoperatively. Between 5 and 36 h, the TTSF groups had significantly increased abnormal respiratory pattern including apneic episodes (tidal volume of less than 100 ml for more than 15 s) and episodes of slow respiratory rate (less than 8 breaths/min persisting for more than 5 min) and significantly increased requirement for oxygen supplementation. Nine patients in the TTSF groups were withdrawn because of severe respiratory depression compared to none in the placebo group. No significant between-group differences were present in the incidence of nausea, vomiting, or pruritus. Although fentanyl plasma concentration was higher in the TTSF-75 group than in the TTSF-50 group, the differences were not significant. Fentanyl plasma concentration decreased significantly 48 h after patch application.Application of TTSF patches 2 h preoperatively is associated with moderate supplementary opioid requirements for analgesia in the early postoperative period and ongoing opioid supplementation for at least 72 h. Although good analgesia is the result of this combination therapy, it is associated with a high incidence of respiratory depression requiring intensive monitoring oxygen supplementation, removal of the TTSF patches in approximately 11% of the patients and opioid reversal with naloxone in approximately 8% of the patients.

Two cases of cardiac tamponade caused by dissections of the ascending thoracic aorta are described. Despite uneventful induction of anaesthesia one patient exsanguinated following sternotomy and release of pericardial tamponade as the resulting increase in blood pressure caused aortic rupture. The second patient was managed with femoral-femoral bypass, propranolol and vasodilators prior to sternotomy to avoid this complication, and he survived. The anaesthetic management of a patient with cardiac tamponade is directed towards maintaining cardiac filling pressures and contractility. When the tamponade is released the sudden increase in cardiac output and blood pressure may cause the already weakened aorta to rupture.