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Background: Few data exist regarding the effectiveness of simulation in resident education in critical care. The purpose of this study was to determine whether multiple-simulation exposure (MSE) or single-simulation exposure (SSE) improved residents' recognition of shock and initial management of the critically ill simulated surgical patient., Methods: Data were collected at a level 1 trauma center. Surgery, anesthesiology, and emergency medicine residents were given a multiple-choice question (MCQ) pretest before a tutorial on the recognition and management of shock followed by high-fidelity simulation/debriefing and MCQ post-test. MSE residents had 1.5 hours of simulation per resident over 3 days, and SSE residents had 1.5 hours of simulation as a group in 1 day. Pre- and posttest comparisons overall and subgroup analysis for MSE versus SSE were performed., Results: Data was available for 45 MSE residents and 15 SSE residents. Overall posttest percent correct was greater than pretest percent correct (81% ± 9% vs 75% ± 13%, post- versus pre-, P = .01). Subgroup analysis demonstrated significantly improved post- versus pretest performance for MSE residents only. There were no differences in pre- or posttest performance for MSE residents during the first 4 months of the academic year versus the last 4 months. Pretest performance over 12 months of observation for MSE residents showed no significant differences., Conclusion: Repeated simulation exposure was more effective than single simulation exposure at improving MCQ performance designed to measure the recognition and management of shock in the critically ill simulated surgical patient. Duration of training did not impact MCQ performance., (Copyright © 2013 Mosby, Inc. All rights reserved.)

Background: The management of severe hepatic trauma frequently involves exposing the liver to varying periods of warm ischemia. The ischemic tolerance of the liver, in the setting of hemorrhagic shock (HS) and trauma, is presently unknown. We tested the hypothesis that warm ischemic tolerance of the porcine liver will be decreased following resuscitation from HS., Materials and Methods: Twenty-three Yorkshire pigs were divided into three groups: 1) hepatic ischemia alone (HI, n = 9); 2) hemorrhagic shock alone (HS, n = 3); and 3) hemorrhagic shock plus hepatic ischemia combined (HSHI, n = 11). Following reperfusion, a liver biopsy was obtained and serial blood chemistries were sampled., Results: Post-operative day 7 mortality was increased in the HSHI group (7/11) compared to the HI (0/9) group, P = 0.038. Notably, deaths did not result from acute liver failure, but rather from intra-operative hemodynamic collapse shortly following hepatic reperfusion. In addition, the HSHI group experienced significantly elevated lactic acid, serum creatinine and liver enzyme levels. Analysis of the liver biopsy samples is consistent with a more severe liver injury in the HSHI group., Conclusions: The warm ischemic tolerance of the liver following resuscitation from HS is significantly decreased in this porcine model compared to HS or HI alone. Mortality was associated with acute intra-operative hemodynamic collapse occurring shortly after hepatic reperfusion.

Flow-through chip thermocyclers can be used in miniaturized rapid polymerase chain reaction (PCR) despite their high surface to volume ratio of samples. We demonstrated that a thermocycler made of silicon and glass chips and containing thin film transducers for heating and temperature control can be adapted to the amplification of various DNA templates of different sources and properties. Therefore, the concept of serial flow in a liquid/liquid two-phase system was combined with a surface management of inner side walls of the microchannel and an adaptation of PCR mixture composition. In addition, the process temperatures and the flow rates were optimized. Thus, a synthetic template originating from investigations on nucleic acid evolution with 106 base pairs [cooperative amplification of templates by cross hybridization (CATCH)], a house keeping gene with 379 base pairs [glutaraldehyde 3-phosphate dehydrogenase (GAPDH)] and a zinc finger protein relevant in human pathogenesis with 700 base pairs [Myc-interacting zinc finger protein-1, knock-out (Miz1-KO)] were amplified successfully. In all three cases the selectivity of priming and amplification could be shown by gel electrophoresis. The typical amplification time was 1 min per temperature cycle. So, the typical residence time of a sample volume inside the 25 cycle device amounts to less then half an hour. The energy consumption of the PCR chip for a 35 min PCR process amounts to less than 0.012 kW h.

Background: A new Definitive Surgical Trauma Care course was developed to educate surgeons in operative management of injuries. The course consists of an interactive CD-ROM and a live porcine animal laboratory., Method: A five-hour session was conducted. Penetrating injuries to stomach, bowel, diaphragm, spleen, pancreas, kidney, ureter, inferior vena cava, liver, and heart were created by the senior surgeon and managed by the junior surgeon. Participants rated their expertise in 26 maneuvers pre- and post-lab. The evaluation scale used was: no prior experience; able to perform skill with assistance; proficient at procedure; able to teach procedure to another surgeon., Results: In 26 procedures, a maximum score of 78 was possible. There was an increase from pre- to post-session scores of 22.6 for PGY-4 residents (n = 3); 23.3 for PGY-5 residents (n = 4); 11.25 for fellows (n = 4); and 0 for attendings (n = 4)., Conclusion: The operative animal session had the greatest educational benefit among surgeons without formal training in trauma surgery. By exposing them to a range of trauma-induced surgical conditions, the DSTC course develops their operative repertoire and should increase their effectiveness in managing trauma patients.

To evaluate the effects of programmed ventricular stimulation on resultant plasma concentrations of intravenously administered procainamide, drug dosing was performed with and without ventricular stimulation on two separate days (48 hours apart) in 12 dogs (13 dosing trials) at > or = 14 days after myocardial infarction (mean: 62 days). During infarct surgery, three bipolar electrodes were plunged into left ventricular epicardium, externalized, and later used for ventricular stimulation. On the first study day, procainamide was dosed to achieve two sequential plateau plasma levels (I and II), with a 20-minute equilibrium period at each plateau before ventricular stimulation. Plasma procainamide concentrations were measured before initiation of ventricular stimulation and at the completion of ventricular stimulation for each sequential plateau level. Stimulation involved delivery of one, two, and three extrastimuli at three paced cycle lengths at three left ventricular sites before procainamide dosing and at each of the two procainamide plateau levels. Three dogs were excluded from analysis due to induction of lethal ventricular arrhythmias. No ventricular arrhythmias were induced in the remaining nine animals. On the second study day, procainamide was dosed identically, but no ventricular stimulation was performed. Intravenous drug administration and collection of plasma concentration samples were performed with +/- 1 minute on both study days. Mean plasma procainamide concentrations at the end of ventricular stimulation at dosage Levels I & II were 10% and 12% greater (P < 0.02 and P < 0.005, respectively) than plasma concentrations measured at comparable times on the study day when no ventricular stimulation was performed.(ABSTRACT TRUNCATED AT 250 WORDS)

We constructed and surgically implanted 114 chronic bipolar epicardial plunge electrodes for programmed left ventricular stimulation in closed chest dogs; 88 electrodes could be analyzed in animals surviving infarct surgery. Electrode plunges were constructed of silver wire, with conduction strands of silver-plated copper wire, in medical grade silicone tubing. Electrodes were implanted epicardially through left thoracotomy and secured with prolene. Wires exited the fifth intercostal space and were tunneled subcutaneously and secured at the dorsal aspect of the neck. Baseline thresholds (mA) were recorded at a paced cycle length of 300 ms and pulse duration of 1 ms. At least 5 days after implantation, under light Nembutal sedation, thresholds were reassessed before programmed stimulation. Each lead was tested repeatedly over 5-177 (mean 28) days. The number of leads decreased with time due to animal attrition from ventricular arrhythmias. Mean pacing threshold at implantation was 0.25 mA. Mean and median threshold values reached plateau after 1 week and showed little change thereafter for the duration of the study. More than 50% of the leads maintained thresholds less than 1.5 mA through the entire study. In animals that survived, 86% of the electrodes remained useful for the duration of the protocol. These data support the use of this electrode system as effective and reliable for chronic electrophysiologic studies in dogs.