Comparison of minithoracotomy with conventional sternotomy methods in valve surgery.

BACKGROUND: To determine the differences in the operative findings between the two groups of patients who had undergone either minithoracotomy or conventional sternotomy. METHODS: We compared 12 valve operations that were performed in our clinic with minithoracotomy (group I) between January 1997 and November 1999 with 13 valve operations that were performed with conventional median sternotomy (group II) in the same period in regard to preoperative, perioperative and postoperative variables, retrospectively. Preoperative variables were age, sex, bleeding time, clotting time, platelet count, and additional diseases like diabetes mellitus, hypertension, etc. Perioperative variables were extracorporeal circulation (ECC) time, cross-clamp (CC) time, and operation time. Postoperative variables were mechanical ventilation period, stay in the postoperative intensive care unit and hospital, mediastinal drainage amount, the amount of blood and blood products for transfusions, and costs. Group I consist of six mitral valve replacements (MVRs), three aortic valve replacements (AVRs), one aortic valve replacement combined with mitral valvuloplasty, and two tricuspid valve replacements (TVRs). Group II consist of nine MVRs and four AVRs. RESULTS: Statistical results are given with mean standard error (SEM) deviations. There were significant differences between the two groups in respect to operation time (in group I, mean operation time was 328 +/- SEM 22 minutes in group II, 271 +/- SEM 14 minutes (p < 0.04)); mediastinal drainage (in group I, mean drainage time was 283 +/- SEM 57 cc/m2, in group II, 490 +/- SEM 74 cc/m2 (p < 0.04)); and amounts of transfused blood and blood products (in group I, mean transfused blood products amount was 375 +/- SEM 115 cc/m2, in group II, 874 +/- SEM 184 cc/m2 (p < 0.03)). CONCLUSION: The operation times are apparently longer in the minithoracotomy group. On the other hand, less mediastinal drainage occurred and less blood and blood products transfusion needs were determined to exist in the minithoracotomy group.

Coronary artery stabilization causes endothelial damage: an electron microscopic study on dogs.

In recent years, to protect patients from adverse effects of cardiopulmonary bypass, off-pump coronary artery bypass operations are performed. In these operations, effective coronary artery immobilization is the standard for a fine anastomosis. This is usually maintained with the help of prolene immobilization sutures, bulldog occluders or mechanical epicardial devices. The aim of this study is to show whether these stabilization devices cause any damage to the coronary artery endothelium. Sixteen dogs are included in this study and are divided into four groups. The control group consisted of one dog (Group I) and different immobilization techniques are applied to the other groups, which were five dogs each (Groups II, III, and IV). Coronary artery biopsies are obtained, then the samples are studied under scanning electron microscope (SEM) for endothelial injury and all samples are scored. Among the techniques used, bulldog occluders caused less injury on the coronary endothelium than the prolene sutures.

Effects of hypothermia on blood endogenous endotoxin levels during cardiopulmonary bypass.

Endotoxin activates white blood cells and complement and produces a spectrum of clinical syndromes ranging from fever to septic shock. Although production of endogenous endotoxemia during cardiopulmonary bypass (CPB) has recently been reported, the role of hypothermia on endotoxemia is not clear. In this study, we evaluated the effects of moderate (24-28 degrees C) and mild (32-34 degrees C) hypothermia on blood endotoxin levels. The study population consisted of 20 patients who underwent coronary artery bypass grafting (CABG) with CPB. Moderate systemic hypothermia was applied during aortic cross-clamping in ten patients (group 1) and mild hypothermia in the remaining ten patients (group 2). The mean rectal temperatures were 26.8 +/- 1.2 degrees C in group 1 and 33.8 +/- 0.8 degrees C in group 2. The blood samples for endotoxin level measurements were obtained before CPB, during aortic cross-clamping, immediately after the release of the cross-clamp, 20 minutes after the release of the cross-clamp, after CPB, and 2 hours postoperatively. There were no endotoxins in any of the samples before CPB, but it was detected after CPB in both groups. The endotoxin levels were significantly higher in group 1 than in group 2. The present study suggests that when hypothermia is the technique of choice, the deleterious effects of endotoxemia on patients with comorbidity must be considered.