Factors affecting postoperative ventilatory support in patients with cardiac cachexia

Factors affecting early v late weaning from ventilatory support after cardiac surgery were retrospectively compared in 15 patients with cardiac cachexia. These patients were divided into two groups based on the duration of postoperative ventilatory support, group I (n = 7) less than two days (22 +/- 8 hours) and group II (n = 8) over three days (140 +/- 125 hours). Findings in 14 randomly selected patients without cardiac cachexia who underwent cardiac valve replacement were also examined. Comparisons were made between the groups in regards to the following parameters: (1) preoperatively: anthropometric, biochemical, and immunologic parameters of nutritional status, hepatic function, cardiothoracic ratio (CTR) on chest x-ray, and data from cardiac catheterization; (2) intraoperatively and postoperatively: anesthetic drugs, duration of surgery, cardiopulmonary bypass (CPB), aortic cross-clamp, and postoperative use of inotropes. The anthropometric measurements, cell-mediated immunity, and hepatic function were significantly decreased in all patients with cachexia, but with no significant differences between the groups. Serum transferrin levels, which increased in patients with cachexia, showed no significant difference between the groups. The levels of serum albumin were significantly lower in cachectic patients than in patients without cachexia; they were significantly higher in group II than in group I. The durations of surgery and CPB were significantly longer in group II, but there was no significant difference in the duration of aortic clamping between the groups. The postoperative use of inotropes was higher in group II. These results indicate that group II patients were nutritionally as well sustained as group I. However, they had less satisfactory cardiac function, and therefore required a longer duration of postoperative ventilatory support.