Central Circulatory Function Early After Pulmonary Surgery

In 45 patients with a clinically normal circulation the circulatory function was studied before and on three consecutive days after pulmonary surgery. After operation a consistent decrease in stroke volume was found in combination with an increased heart rate and an unaltered or slightly elevated cardiac output. The pulmonary arterial mean pressure tended to increase while the left atrial pressure decreased consistently. The calculated pulmonary vascular resistance was consistently increased after operation. The 10 patients who later developed cardiac arrhythmias were compared with those who did not. The postoperative “blood loss” was found to be significantly higher in the patients who developed arrhythmias than in those who did not but more blood was also supplied. As postoperative blood loss often is underestimated the findings indicate that the arrhythmia patients may have been more hypovolemic than the others. Certain other factors such as arterial hypoxaemia, carbon-dioxide retention, blood electrolyte alterations or cardiac failure could be excluded as general causes of the arrhythmia.