Effect of a behavioral intervention on anxiety and perceived performance of non-technical skills during surgical simulations.

BACKGROUND: Surgical trainees experience intrinsic stress and anxiety during high-acuity clinical situations which can negatively impact performance. Emerging data suggests that education in mindfulness-based coping techniques may improve performance. We evaluated the effects of a stress recovery intervention on novice trainees' perceived level of anxiety during an intentionally stressful simulation. METHODS: Participants were recruited from surgical intern classes over three consecutive years. All participants completed a simulation intentionally designed to evoke a stress response. Participants then completed a stress recovery intervention or received no additional training. All participants then completed a second novel simulation. RESULTS: Intervention participants had significantly higher self-reported ability to manage stress (intervention 2.4 to 3.6, p < 0.01; control 2.8 to 3.3, p = 0.06), and stop, think, and observe (intervention 2.5 to 3.7, p < 0.01; control 2.6 to 3.3, p = 0.08) during the second simulation. Both groups also had significantly lower levels of state anxiety during the second simulation as compared to the first (intervention 45.1 vs 59.3, p < 0.01; control 49.3 vs 57.4, p < 0.05). During the second simulation, trainees in both groups reported improvements in perceived abilities to: recognize stress (intervention 2.7 to 4.1, p < 0.01; control 2.9 to 3.6, p < 0.05), communicate with and lead their team (intervention 2.4 to 3.3, p < 0.05; control 2.3 to 3.3, p < 0.01), and to prioritize, plan, and prepare (intervention 2.1 to 3.1, p < 0.05; control 2.1 to 3.0, p < 0.01). CONCLUSION: Our research shows that a brief intervention was associated with a significant increase in trainee ability to both recognize internal stress and engage in proactive coping mechanisms. This research also shows that while repeated stress-inducing simulations may themselves decrease perceived anxiety levels in novice surgical trainees, training in coping strategies may potentiate this effect.

Nonparticulate components of diesel exhaust promote constriction in coronary arteries from ApoE-/- mice.

Air pollution is positively associated with increased daily incidence of myocardial infarction and cardiovascular mortality. We hypothesize that air pollutants, primarily vapor phase organic compounds, cause an enhancement of coronary vascular constriction. Such events may predispose susceptible individuals to anginal symptoms and/or exacerbation of infarction. To develop this hypothesis, we studied the effects of nonparticulate diesel exhaust constituents on (1) electrocardiographic traces from ApoE-/- mice exposed whole-body and (2) isolated, pressurized septal coronary arteries from ApoE-/- mice. ApoE-/- mice were implanted with radiotelemetry devices to assess electrocardiogram (ECG) waveforms continuously throughout exposures (6 h/day x 3 days) to diesel exhaust (0.5 and 3.6 mg/m3) in whole-body inhalation chambers with or without particulates filtered. Significant bradycardia and T-wave depression were observed, regardless of the presence of particulates. Pulmonary inflammation was present only in the whole exhaust-exposed animals at the highest concentration. Fresh diesel exhaust or air was bubbled through the physiologic saline tissue bath prior to experiments to enable the isolated tissue exposure; exposed saline contained elevated levels of several volatile carbonyls and alkanes, but low to absent levels of polycyclic aromatic hydrocarbons. Vessels were then assayed for constrictive and dilatory function. Diesel components enhanced the vasoconstrictive effects of endothelin-1 and reduced the dilatory response to sodium nitroprusside. These data demonstrate that nonparticulate compounds in whole diesel exhaust elicit ECG changes consistent with myocardial ischemia. Furthermore, the volatile organic compounds in the vapor phase caused enhanced constriction and reduced dilatation in isolated coronary arteries caused by nonparticulate components of diesel exhaust.

Extracorporeal membrane oxygenation support improves survival of patients with Hantavirus cardiopulmonary syndrome refractory to medical treatment.

OBJECTIVE: The aim of the study was to evaluate the outcome of extracorporeal membrane oxygenation (ECMO) support in Hantavirus cardiopulmonary syndrome (HCPS) patients with a predicted mortality of 100%, and the complications associated with this treatment modality and different cannulation techniques. METHODS: A total of 51 patients with refractory HCPS were supported with ECMO between April 1994 and June 2010. They were divided into group A consisting of the 26 patients treated between 1994 and 2000 and group B consisting of 25 patients treated between 2003 and 2010. No patients were treated between September 2000 and December 2003. Patients in group A were intubated when they became hypoxic and placed on ECMO when they became hemodynamically unstable, whereas patients in group B had elective insertion of vascular sheaths and were almost concurrently intubated and placed on ECMO when they decompensated. Cannulation of the femoral vessels was performed percutaneously in 18 (35.3%) patients and with an open technique in 33 (64.7%) patients. RESULTS: Complications from percutaneous cannulation occurred in 4/18 (22.27%) patients: retroperitoneal hematoma in 2/18 (11.1%) and lower-extremity ischemia in 2/18 (11.1%) patients. Complications from open femoral cannulation occurred in 12/33 (36.3%) patients: bleeding in 10/33 (30.3%) patients and ischemia in 2/33 (6.1%) patients. The overall survival was 66.6% (34 of 51 patients); 56% (14/26) for group A and 80% (20/25) for group B (p = 0.048). There was no difference in mortality regarding the method of cannulation. A trend toward increased mortality in patients with cannulation complications was recognized, but it was not statistically significant. Mortality was not associated with ECMO duration (average 121.7h, range: 5-276h). All survivors recovered and were discharged from the hospital after a mean hospital stay of 19.8 days (range: 10-39 days). CONCLUSIONS: Two-thirds of 51 HCPS patients with a predicted mortality of 100%, who were supported with ECMO, survived and recovered completely. Survival was significantly higher in the second half of the study. Complications associated with both types of femoral cannulation were associated with a trend toward decreased survival, which was not significant.

Extracorporeal membrane oxygenation support improves survival of patients with severe Hantavirus cardiopulmonary syndrome.

OBJECTIVE: The purposes of this study are to evaluate the outcome of extracorporeal membrane oxygenation support in a subgroup of patients with Hantavirus cardiopulmonary syndrome who had a predicted mortality of 100% and to assess the complications associated with this treatment modality and with different cannulation techniques. METHODS: Thirty-eight patients with severe Hantavirus cardiopulmonary syndrome were supported with extracorporeal membrane oxygenation between April 1994 and June 2006. Cannulation of the femoral vessels was performed on an emergency basis by a percutaneous approach in 15 (39.5%) and by an open technique in 23 (60.5%) patients. Duration of extracorporeal membrane oxygenation averaged 132 hours (range: 5-276 hours). RESULTS: Complications from percutaneous cannulation occurred in 4 (26.6%) of 15 patients: retroperitoneal hematoma in 2 (13.3%) and lower extremity ischemia in 2 (13.3%) patients, which resolved after insertion of a distal perfusion cannula. Complications from open femoral cannulation occurred in 8 (34.8%) of 23 patients: severe bleeding in 7 (30.4%) patients and lower extremity ischemia in 1 (4.3%) patient who required a leg amputation. The overall survival was 60.5% (23/38 patients). Six (40%) of the 15 patients cannulated percutaneously and 9 (39.1%) of 23 patients who had open cannulation died. All survivors recovered completely and were discharged from the hospital after a mean hospital stay of 20.8 days (range: 10-39 days). CONCLUSIONS: Almost two thirds of the patients with severe Hantavirus cardiopulmonary syndrome who were supported with extracorporeal circulation survived and recovered completely. The complications associated with both types of femoral cannulation may be attributed to the fact that all patients were in shock or in full cardiac arrest, and the procedure had to be done expeditiously. Earlier institution of extracorporeal membrane oxygenation may decrease the complication rates and improve the overall survival.

Ischemia, reperfusion, and the role of surgery in the treatment of cardiogenic shock secondary to acute myocardial infarction: an interpretative review.

Cardiogenic shock (CS) is the leading cause of death for patients hospitalized with acute myocardial infarction (AMI). Despite contemporary management of AMI, the incidence of shock due to left ventricular failure has not declined and its mortality continues to be in excess of 50%. Furthermore, the role and indications of the different means of acute revascularization remain unclear. Recent observational and randomized studies have shown improved survival in patients acutely revascularized by either percutaneous interventions or conventional surgery, particularly in patients younger than 75 years of age. Current guidelines recommend surgical revascularization in selected patients with multiple vessel disease who develop shock due to progressive ischemia of the remote myocardium up to 18 h from the onset of shock. However, patients with single-vessel disease who develop shock as a consequence of the initial infarction can only be helped if revascularization is achieved during the first 4 to 6 h after the occlusion of the infarct related artery, preferable by percutaneous techniques. Not all ischemic myocytes become irreversibly injured at the same time. Due to variability in the distribution of collateral flow, there is great variability in the severity of ischemia. Myocytes can exhibit different metabolic responses including hibernation, ischemic preconditioning, stunning, reperfusion injury, and necrosis. Precise knowledge of these biochemical and metabolic changes that take place in the myocardium after arterial occlusion and following reperfusion is paramount to the understanding of the indications for acute revascularization, the implementation of the different management strategies to enhance myocardial preservation and recovery, and the role of circulatory support in these exceedingly sick patients.