Does A Low 6-Minute Walk Distance Predict Elevated Postoperative Troponin?

Our study of 100 major vascular and renal transplant patients evaluated the 6-minute walk test (6MWT) as an indicator of perioperative myocardial injury, using troponin as a marker. Using logistic regression and the area under the receiving operator characteristic curve, we compared the 6MWT to the Revised Cardiac Risk Index and metabolic equivalents. Only the 6MWT was associated with elevated postoperative troponins (95% CI, 0.98-0.99). However, the 6MWT area under the receiving operator characteristic curve (0.71 [95% CI, 0.57-0.85]) was not different from the Revised Cardiac Risk Index (P = .23) or metabolic equivalents (P = .14). The 6MWT may have a role in cardiac risk stratification in the perioperative setting.

Ventilator Failure Following Cardiopulmonary Bypass: A Case Report.

We present 3 cardiothoracic surgery cases during which the Drager Perseus A500 anesthesia machine and the iNOmax Delivery System were used concurrently, resulting in ventilator failures while attempting to separate from cardiopulmonary bypass (CPB). The failure was found to be caused by the iNOmax Delivery System sampling line, where negative pressure on the Perseus A500 breathing circuit precipitated a ventilator failure when the machine was brought out of "standby mode." To our knowledge, there is no discussion of this interaction in the literature, and we find this to be an important issue for patient safety during cardiothoracic surgery.