Mild hypothermia during cardiopulmonary bypass assisted CABG is associated with improved short- and long-term survival, a 18- year cohort study

Data substantiating the optimal patient body temperature during cooling procedures in cardiac operations are currently unavailable. To explore the optimal temperature strategy, we examined the association between temperature management and survival among patients during cardiopulmonary bypass assisted coronary artery bypass grafting (CABG) procedures on 30-days and 5-year postoperative survival. Adult patients (n = 5,672, 23.6% female and mean (SD) age of 66 (10) years) operated between 1997 and 2015 were included, with continuous measured intraoperative nasopharyngeal temperatures. The association between mortality and patient characteristics, laboratory parameters, the lowest intraoperative plateau temperature and intraoperative cooling/rewarming rates were examined by multivariate Cox regression analysis. Machine learning-based cluster analysis was used to identify patient subgroups based on pre-cooling parameters and explore whether specific subgroups benefitted from a particular temperature management. Mild hypothermia (32- 35°C) was independently associated with improved 30-days and 5-year survival compared to patients in other temperature categories regardless of operation year. 30 days and 5-year survival were 98% and 88% in the mild hypothermia group, whereas it amounted 93% and 80% in the severe hypothermia (<30°C). Normothermia (35-37°C) showed the lowest survival after 30 days and 5 years amounting 93% and 72%, respectively. Cluster analysis identified 8 distinct patient subgroups principally defined by gender, age, kidney function and weight. The full cohort and all patient subgroups displayed the highest survival at a temperature of 32°C. Given these associations, further prospective randomized controlled trials are needed to ascertain optimal patient temperatures during CPB

A randomized study comparing three bronchial blockers, Arndt®, Coopdech® and EZ-blocker® and a double-lumen tube for lung isolation:A manikin study

Background and Goal of Study: Double-lumen tubes (DLT) and bronchial blockers (BB) are used for lung isolation and one lung ventilation during thoracic surgery. Recently1 a new Y shaped bronchial blocker was developed, the EZ-Blocker, with two distal extensions to be placed in the two main stem bronchi. In a manikin model we compared lung isolation achieved with this new Y shaped blocker to the conventional Arndt BB and Coopdech BB, and a left sided DLT. Materials and Methods: After instruction, 20 anesthesiologists intubated a manikin (Laerdal, Stavanger, Norway) with a single lumen tube (SLT) and a DLT as training. Next the sequence of the SLT (Mallinckrodt 8.0) versus DLT (Mallinckrodt 37Fr, leftsided) and BB (Arndt BB 9Fr, Cook Critical Care, Bloomington, USA; Coopdech BB, Smith Medical, Rosmalen, NL; EZ-blocker, AnaesthetIQ, Rotterdam, NL) were randomized. Intubation time and success rate (checked by fiber optic bronchoscopy, FOB) were recorded. After intubating with the SLT the different BB were introduced under guidance of a FOB into the left main stem bronchus. Time from introduction of the BB in the SLT until reaching appropriate position was recorded and position was checked. Data are expressed as mean ± SD, failure rate as percentage and compared using T-test and χ2 test respectively, with p< 0.05 considered statistically different. Results and Discussion: This study demonstrates that lung isolation with a DLT was achieved significantly faster compared to the different blockers. Isolation time between the blockers (table) did not differ significantly. However, the blockers had a higher success rate compared to the DLT (55%). The Arndt BB was the least successful BB (75%). Lung isolation with the EZ-blocker and Coopdech was successful in all cases. Malpositioning of the Arndt BB consisted of introduction into the right main stem bronchus. Malpositioning of the DLT consisted of introduction into the right main stem bronchus or because the tip was placed too deep.  Conclusion(s): Because of the high success rates the EZ-Blocker and the Coopdech BB seem to be preferable to both the Arndt BB and the DLT. References: 1. BJA 2010;104:119-12