Pulmonary toxicity of Expancel microspheres in the rat.

Expancel microspheres are thermoplastic microspheres enclosing hydrocarbon. These microspheres expand when heated, producing many applications. Because they have unknown biological persistence and toxicity, we investigated the toxicity of two unexpanded (11.1 and 15.4 micro m mean diameter) and two expanded (3.1 and 5.5 micro m mass median aerodynamic diameter) Expancel microspheres in intratracheally-instilled, male, Sprague-Dawley rats. Pulmonary histopathology was evaluated at 28 days postexposure. Bronchoalveolar lavage fluid was evaluated at days 1, 7, 14, and 28 days postexposure. Crystalline silica was the positive control. By histopathology, both unexpanded and expanded microspheres caused granulomatous bronchopneumonia characterized by macrophages and giants cells, suggesting a persistent foreign body response. Expanded, but not unexpanded microspheres, also caused eosinophilic bronchitis and bronchiolitis, mucous metaplasia of airways and organized granulomatous inflammation with associated fibrosis and frequent airway obstruction. In contrast, alveolar macrophage activation, polymorphonuclear leukocytes, LDH and albumin in bronchoalveolar laveage fluid were initially elevated but returned to near control levels at 28 days, and did not reflect the persistent granulomatous bronchopneumonia caused by Expancel microspheres. These findings emphasize the importance of histopathology for evaluating pulmonary toxicity, suggest that Expancel microspheres are a potential occupational hazard, and indicate a need for additional studies on their potential pulmonary toxicity. [Supplementary materials are available for this article. Go to the publisher's online edition of Toxicology Pathology for the following free supplemental resources: motion within unexpected microspheres in H&E-stained lung (supplementary Figure 1); broncholar epithelium 28 days following exposure to 551 DE 20 microspheres (supplementary Figure 2); membrane ruffling and some instances of phagocytosis within the microspheres (supplementary Figure 3)]

The Buffalo Cardio-Metabolic Occupational Police Stress (BCOPS) pilot study: methods and participant characteristics.

PURPOSE: The Buffalo Cardio-Metabolic Occupational Police Stress (BCOPS) study is one of the first population-based studies to integrate psychological, physiological, and subclinical measures of stress, disease, and mental dysfunction. This pilot study was undertaken to establish a methodology and descriptive results for a larger police study. METHODS: A stratified sample of 100 officers was randomly selected from the Buffalo, NY Police Department. Salivary cortisol served as a stress biomarker. Flow mediated dilation (FMD) and carotid intima-media thickness (IMT) were performed with ultrasound. Dual Energy X-Ray Absorptiometry (DEXA) and anthropometric measures assessed body composition. Self-report measures of depression and posttraumatic stress disorder (PTSD) were obtained. RESULTS: Recruitment attained for the study was 100%. Seventy-five percent showed a cortisol increase upon awakening, 90% a negative diurnal slope, and 77% an increased cortisol response after a high protein lunch challenge. Dexamethasone suppression was evident. FMD showed an increase in mean brachial artery diameter of 3.2% in men and 3.9% in women, and mean IMT was lower (male=0.67 mm; female=0.62 mm) compared to populations of similar age. For males, the mean body-mass index (BMI) was 29.8 kg/m2 and total body fat 23.4%. For females, the mean BMI was 26.7 kg/m2 and total body fat 31.5%. For all officers, 16% met criteria for depression; 36% reported elevated PTSD symptoms. CONCLUSIONS: Compared to populations of similar age, police officers had slightly lower FMD, lower carotid IMT, elevated BMI, and higher reported rates of depression and PTSD. Standardized physiological and psychological data collection and descriptive results confirmed that the methodology of the study is feasible in a working police population.

Current transfusion practices of members of the american society of anesthesiologists: a survey.

BACKGROUND: The last published survey of transfusion practices among members of the American Society of Anesthesiologists (ASA) was conducted in 1981. The ASA Committee on Transfusion Medicine conducted a new transfusion survey in 2002. METHODS: The survey was mailed to 2,500 randomly selected active ASA members. The previous survey was modified to incorporate questions based on the ASA Practice Guidelines for Blood Component Therapy. The chi-square test was used for comparisons. Two-tailed P values of 0.05 or less were considered as nonchance differences. RESULTS: A total of 862 survey responses were completed by anesthesiologists who provided or directly supervised anesthesia for patients who may have required transfusion. In a given week, 62% rarely or never transfused 3 or more units of blood to the same patient. The percentage of anesthesiologists who responded that it is never or rarely (1% or less of the time) necessary to cancel elective surgery because of unavailability of blood products was 96% in 2002. In 1981, 92% responded that it was rarely necessary, and 8% said that it was occasionally necessary. The percentage of anesthesiologists who required patients undergoing elective surgery to have a hemoglobin concentration of at least 10 g/dl decreased from 65% to 9% (P < 0.001). Before intraoperative erythrocyte transfusion, 89% of respondents performed hemoglobin or hematocrit determinations routinely or sometimes. Intraoperative autologous transfusion equipment availability increased from 39% to 95% (P < 0.001). Awareness of the ASA Guidelines was 72%. CONCLUSIONS: Transfusion practices have changed considerably since 1981. Current transfusion practices are, in general, consistent with the ASA Guidelines.

A comparison of psoas compartment block and spinal and general anesthesia for outpatient knee arthroscopy.

UNLABELLED: The optimal anesthetic technique for outpatient knee arthroscopy remains controversial. In this study, we evaluated surgical operating conditions, patient satisfaction, recovery times, and postoperative analgesic requirements associated with psoas compartment block, general anesthetic, or spinal anesthetic techniques. Sixty patients were randomized to receive a propofol/nitrous oxide/fentanyl general anesthetic, spinal anesthesia with 6 mg of bupivacaine and 15 micro g of fentanyl, or psoas compartment block with 40 mL of 1.5% mepivacaine. All patients received IV ketorolac and intraarticular bupivacaine. The frequency of postanesthesia recovery room admission was 13 (65%) of 20 for patients receiving general anesthesia, compared with 0 of 21 for patients receiving spinal anesthesia and 1 (5%) of 19 for patients receiving psoas block (P < 0.001). The median time from the end of surgery to meeting hospital discharge criteria did not differ across groups (131, 129, and 110 min for general, spinal, and psoas groups, respectively). In the hospital, 45% of general anesthesia patients received opioid analgesics, compared with 14% of spinal anesthesia and 21% of psoas block patients (P = 0.087). There was no difference among groups with respect to the time of first analgesic use or the number of patients requiring opioid analgesia. Pain scores were highest in patients receiving general anesthesia at 30 min (P = 0.032) and at 60, 90, and 120 min (P < 0.001). Patient satisfaction with anesthetic technique (P = 0.025) and pain management (P = 0.009) differed significantly across groups; patients receiving general anesthesia reported lower satisfaction ratings. We conclude that spinal anesthesia or psoas block is superior to general anesthesia for knee arthroscopy when considering resource utilization, patient satisfaction, and postoperative analgesic management. IMPLICATIONS: Outpatient knee arthroscopy may be performed using a variety of anesthetic techniques. We report that spinal anesthesia and psoas compartment block are superior to general anesthesia when considering resource utilization, patient satisfaction, and postoperative analgesic management.

Predictors of survival following cardiac arrest in patients undergoing noncardiac surgery: a study of 518,294 patients at a tertiary referral center.

BACKGROUND: The authors determined the incidence of cardiac arrest and predictors of survival following perioperative cardiac arrest in a large population of patients at a tertiary referral center. METHODS: Medical records of patients who experienced cardiac arrest in the perioperative period surrounding noncardiac surgery between January 1, 1990, and December 31, 2000, were reviewed. Logistic regression identified characteristics associated with immediate (>or= 1 h) and hospital survival, with P