Ultrashort acting remifentanil is not superior to long-acting sufentanil in preserving cognitive function-a randomized study.

STUDY OBJECTIVE: Postoperative cognitive dysfunction (POCD) is a well-known complication after cardiac surgery and may cause permanent disabilities with severe consequences for quality of life. The objectives of this study were, first, to estimate the frequency of POCD after on-pump cardiac surgery in patients randomized to remifentanil- or sufentanil-based anesthesia and, second, to evaluate the association between POCD and quality of recovery and perioperative hemodynamics, respectively. DESIGN: Randomized study. SETTING: Postoperative cardiac recovery unit, University Hospital. PATIENTS: Sixty patients with ischemic heart disease scheduled for elective coronary artery bypass grafting ± aortic valve replacement. INTERVENTIONS AND HANDLING: Randomized to either remifentanil or sufentanil anesthesia as basis opioid. Postoperative pain management consisted of morphine in both groups. MEASUREMENTS: Cognitive functioning evaluated preoperatively and on the 1st, 4th, and 30th postoperative day using the cognitive test from the Palo Alto Veterans Affairs Hospital. Perioperative invasive hemodynamics and the quality of recovery was evaluated by means of invasive measurements and an intensive care unit discharge score. MAIN RESULTS: No difference between opioids in POCD at any time. A negative correlation was found between preoperative cognitive function and POCD on the first postoperative day (r=-0.47; P=.0002). The fraction of patients with POCD on the first postoperative day was statistically greater in patients with more than 15minutes of Svo2 <60 (P=.037; χ(2) test). Among patients with postoperative ventilation time exceeding 300minutes, more patients had POCD on postoperative day 4 (P=.002). CONCLUSIONS: We could not demonstrate differences in POCD between remifentanil and sufentanil based anaesthesia, but in general, the fraction of patients with POCD seemed smaller than previously reported. We found an association between POCD and both perioperative low Svo2 and postoperative ventilation time, underlining the importance of perioperative stable hemodynamics and possible fast-track protocols with short ventilation times to attenuate POCD.

Outcome of accidental hypothermia with or without circulatory arrest: experience from the Danish Præstø Fjord boating accident.

BACKGROUND: Resuscitation guidelines for the treatment of accidental hypothermia are based primarily on isolated cases. Mortality rates are high despite aggressive treatment aimed at restoring spontaneous circulation and normothermia. METHODS: The present report is based on a boating accident where 15 healthy subjects (median age 16 (range 15-45) years) were immersed in 2 °C salt water. Seven victims were recovered in circulatory arrest with a median temperature of 18.4 °C (range 15.5-20.2 °C). They were all rewarmed with extracorporeal membrane oxygenation (ECMO) and were subsequently evaluated with advanced neuroradiological and functional testing. The remaining 7 had established spontaneous circulation without the use of ECMO. One victim drowned in the accident. RESULTS: The victims that survived the accident without circulatory arrest were predominantly females with a higher body mass index. Victims with circulatory arrest pH on arrival was a median of 6.61 (range 6.43-6.94), with ECMO being established a median of 226 (178-241)min after the accident. Magnetic resonance spectroscopy showed neuronal dysfunction in five. In five victims initial normal white matter spectra progressed to show evidence of abnormal axonal membranes. Based on the seven-level Functional Independence Measure test functional outcome was good in six circulatory arrest victims and in all without circulatory arrest. Mild to moderate cognitive dysfunction was seen in six and severe dysfunction in one circulatory arrest victim. CONCLUSION: Seven patients with profound accidental hypothermic circulatory arrest were successfully resuscitated using a management approach that included extracorporeal rewarming, followed by successive periods of therapeutic hypothermia and sedated normothermia and intensive neurorehabilitation. Seven other hypothermic victims (core temperature as low as 23 °C) that did not suffer circulatory arrest also survived the accident.

Central venous oxygen saturation cannot replace mixed venous saturation in patients undergoing cardiac surgery.

OBJECTIVE: It has been argued that venous oxygen saturation from a central venous catheter (ScvO(2)) could be an inexpensive alternative to mixed venous oxygen saturation (SvO(2)). The aim was to evaluate whether ScvO(2) measurements could replace SvO(2) readings after cardiac surgery and to analyze factors influencing any differences found. DESIGN: A prospective observational study. SETTING: A university hospital. PARTICIPANTS: Twenty patients scheduled for elective cardiac surgery. INTERVENTIONS: Patients were followed postoperatively with corresponding ScvO(2)/SvO(2) measurements. MEASUREMENTS AND MAIN RESULTS: The overall bias between ScvO(2) and SvO(2) was 1.9. In coronary artery bypass graft (CABG) patients, the bias was 0.6 compared with 6.4 in procedures involving aortic valve replacement. In situations with peripheral saturation (SAT) <92%, the bias was 10.7 compared with 0.8 when SAT was >or=99%. In 25.5% of measurements, the ScvO(2) was more than 10% different from SvO(2), and in only 50% the difference was less than 5%. CONCLUSIONS: The ScvO(2) and SvO(2) measurements are not interchangeable, and, especially in patients undergoing aortic valve surgery, this lack of agreement is crucial. However, the present data indicate that ScvO(2) may be used in CABG patients, although it is not completely accurate in terms of absolute venous saturations. A low SAT, low hemoglobin, or low cardiac index increased the venous gap.