Transfusion-related acute lung injury secondary to biologically active mediators.

Transfusion-related acute lung injury is seen following the transfusion of blood components. The reported incidence is approximately 1 in 2000 transfusions. Clinically, it is similar to adult respiratory distress syndrome. The pathophysiology is unclear but has been attributed to HLA antibodies, granulocyte antibodies, and more recently to biologically active mediators in stored blood components. We report a case with laboratory evidence that supports the role of biologically active mediators in the pathogenesis of transfusion-related acute lung injury. To our knowledge, the case reported here is the first to use lipid extractions of patient samples to determine that lipid-priming activity was present at the time transfusion-related acute lung injury was identified clinically.

Operative times, postanesthesia recovery times, and complications during sinonasal surgery using general anesthesia and local anesthesia with sedation.

OBJECTIVE: The goal was to compare complication rates and recovery times in patients undergoing elective septoplasty or endoscopic sinus surgery using local anesthesia with sedation (LAS) versus general anesthesia (GA). METHODS AND PATIENTS: A retrospective chart review of a consecutive sample of 177 patients undergoing elective septoplasty or endoscopic sinus surgery between July 1, 1994, and June 30, 1996, was carried out at our university-based outpatient surgery unit. Outcome measures included total operative time, surgical time, recovery time, and perioperative complications. RESULTS: Total operative and recovery times were shorter in patients undergoing LAS. The frequency of emesis, epistaxis, and nausea were less in the LAS population than in the GA population. Three patients who underwent GA required unplanned admissions. CONCLUSION: This study suggests that in selected patients undergoing sinonasal surgery, LAS may result in shorter total operative times, shorter recovery times, and less frequent nausea, emesis, and epistaxis than GA.

Initial United States clinical trial of robotically assisted endoscopic coronary artery bypass grafting.

OBJECTIVES: With traditional instruments, endoscopic coronary artery bypass grafting has not been possible. This study was designed to determine the clinical feasibility of using a robotically assisted microsurgical system to create endoscopic coronary anastomoses. METHODS AND RESULTS: Ten patients underwent endoscopic coronary artery bypass grafting of the left internal thoracic artery to the left anterior descending artery. Subxiphoid endoscopic ports (2 for instruments, 1 for a camera) were placed, and a robotic system was used to perform the left internal thoracic artery-left anterior descending artery bypass graft. Conventional techniques were used to perform the other grafts. Blood flow through the left internal thoracic artery graft was measured in the operating room and was adequate in 8 of 10 patients. The 2 inadequate grafts were revised successfully by hand. Six weeks after the operation, selective coronary angiography demonstrated a graft patency of 100% (8/8). There were no technical failures of the robotic system. The only postoperative complication was mediastinal hemorrhage in 1 patient. CONCLUSIONS: This pilot study demonstrates the feasibility of robotically assisted endoscopic coronary artery bypass grafting.

The effects of haemofiltration on cefazolin levels during cardiopulmonary bypass.

Ultrafiltration has been shown to affect cardiac drug concentrations during cardiopulmonary bypass (CPB), based on their respective pharmacological properties. In an attempt to understand the aetiology of sternal wound infections, a study was performed to eliminate the use of ultrafiltration as a possible cause. We compared cefazolin levels at three time intervals during the course of routine CPB with ultrafiltration to those levels in a control group in which ultrafiltration was not used. Our results indicate that there is little difference in the rate of decay of antibiotic levels with or without the use of a haemoconcentrator. This implies that ultrafiltration procedures do not put the patient at any increased risk for infection and that additional measures beyond that which we would normally use at our institution need not be taken.

A conscious baboon model for evaluation of hemodynamics in altered gravity.

A model was developed for evaluation of cardiovascular parameters in conscious baboons exposed to altered gravitational environments. Baboons were trained to sit quietly in a confinement chair of unique design which allowed a range of normal physical activity. They were then instrumented with high-fidelity blood pressure transducers in the aorta and left ventricle, electromagnetic flow probes encircling the proximal ascending aorta, left and right atrial fluid catheters, left ventricular sonomicrometer crystals in a 3-axis configuration, and a hydraulic occluder cuff encircling the inferior vena cava. Catheters and transducer wires were exteriorized at the midscapular region of the back. Viability of percutaneous exit sites was enhanced by use of velour cuffs on the transducer wires, providing a scaffold for wound healing. Pressure transducers and flow probes were calibrated and balanced during postoperative cardiac catheterization procedures. This instrumentation allowed measurement of beat-to-beat stroke volume and cardiac output not reliant on thermodilution techniques. Postoperative longevity was from 1 to 10 months. Instrumentation failure included endocardial trapping of ventricular pressure transducers, corrosion of ventricular sonomicrometer crystals, and catheter tip thrombosis. Acquisition of high quality data was possible with this model in several different environments of altered gravitational stress, allowing characterization of aortic flow and ventricular performance.

Effect of volume on spinal anesthesia level with hyperbaric tetracaine.

The purpose of this prospective, randomized, double-blind study was to determine if the volume of a fixed milligram dose of hyperbaric tetracaine hydrochloride injected into the subarachnoid space affected the average maximal dermatomal spread of sensory anesthesia, determined by pinprick testing. One hundred two adults received spinal hyperbaric tetracaine in a volume of 2 mL, 3 mL, or 4 mL with the dose based on the patient's height. The addition of 0.2 mg of epinephrine to the anesthetic solution was allowed at the discretion of the attending anesthesiologist. A two-way analysis of variance (ANOVA) demonstrated that neither the dose selected nor the use of epinephrine affected anesthetic spread. ANOVA showed that anesthetic volume insignificantly affects the spread of sensory anesthesia. A Tukey HSD multiple comparisons test demonstrated a mean difference greater than 1 sensory dermatome between volumes of 2 mL and 4 mL, which was clinically detectable but statistically insignificant. Increasing the volume of hyperbaric spinal tetracaine solutions to improve anesthetic spread is unjustified.

Computer software for the on-line measurement of the left ventricular end-systolic pressure-dimension relationship.

A microcomputer system was designed to measure the end-systolic pressure-dimension relationship (ESPDR), an index of cardiac contractility that is independent of preload, afterload, and heart rate. To test the system, pressure-dimension data were obtained from swine left ventricles and from a mathematical model of the heart. Algorithms for filtering, location of end-systole, selection of the measurement interval, and calculation of the ESPDR were evaluated on the basis of speed, precision, accuracy, and robustness. The resulting program runs on an IBM-AT and measures ESPDR on-line within 60 seconds of the start of data acquisition. By reducing the time spent in data analysis and providing rapid feedback of information, the on-line software has increased productivity and facilitated improvements in experimental technique.

Success of reentry into anesthesiology training programs by residents with a history of substance abuse.

To determine incidence and outcome of reentry into anesthesiology training programs by residents with histories of substance abuse, a survey was sent to the 159 US anesthesiology training programs. One hundred thirteen (71%) responded, with 82 (73%) submitting at least one case report of substance abuse. A total of 180 case reports were submitted, including 26 in which the resident died as a result of substance abuse. The prevalence of substance abuse among trainees was 2%. Sixty-one (74%) of the responding training programs submitted a total of 113 case reports of resident reentry into anesthesiology training. The success rate of reentry in the parenteral opioid abuser group was 34% (27/79). The success rate of reentry for the nonopioid abuser group was 70% (16/23). There were 14 cases of suicide or lethal overdose among trainees who were allowed to reenter anesthesiology training. Death as the initial relapse symptom occurred in 16% (13/79) of the parenteral opioid abusers who were allowed to reenter anesthesiology training. This study suggests that drug rehabilitation followed by redirection into another specialty may be the most prudent course for the anesthesiology trainee who abuses parenteral opioids.

Drawover anesthesia. A review of equipment, capabilities, and utility under austere conditions.

Anesthesia care may be required under austere conditions during military operations and natural disasters. Drawover anesthesia devices that provide inhalational anesthetic agents in air or an air/oxygen mixture are useful in these circumstances. This equipment must be portable, rugged, lightweight, and capable of functioning with an absolute requirement for compressed gas supplies. The historical experience, available equipment and literature on this subject are reviewed.