S-100 levels after aortic surgery with deep hypothermic arrest correlate with the duration of circulatory arrest, indicating that the duration of circulatory arrest is damaging to the brain despite the use of deep hypothermia and partial retrograde cerebral perfusion. The highest correlation between S-100 and duration of arrest was seen on the first postoperative day. S-100 appears to perform well under clinical circumstances as a sensitive and discriminative marker for neuronal injury.

Pericardectomy was performed on 28 men and 8 women (mean age 56, range 18-74 years) with diagnosis constrictive pericarditis. The etiology was unknown in 16 cases. Left anterior thoracotomy was employed in all but one case, in which median sternotomy was preferred because of extensive left pleural calcifications. There were three early and 11 late deaths. Actuarial survival at 5 and 10 years was 77% and 64%, respectively. Relief of symptoms was reported by 16 of the 33 patients (49%), who survived the postoperative period. These 16 were among the 22 survivors observed for a median of 8 (range 2-17) years postoperatively. Complete pericardectomy was achieved in all 16 asymptomatic patients, but in only nine of the 17 hospital survivors (53%), with persistent heart failure (p less than 0.01). Pericardial calcifications were significantly less common in the former than in the latter group. Lack of postoperative improvement was related to severe, nonresectable calcifications, and probably in some cases to associated fibrous epicarditis or restrictive myocardial disease. Left thoracotomy permits easier and more complete left ventricular pericardectomy, but is less safe when severe calcifications involve the right ventricle and atrium.

Correct positioning of the venous cannula draining blood to the cardiopulmonary bypass circuit is important. Intraoperative transesophageal echocardiography allows satisfactory determination of the cannula position in nearly all patients. Ten percent of venous cannulae are primarily positioned in the right hepatic vein and not in the inferior vena cava as intended.

Nitric oxide is present in high concentration in the human nasal airways. During inspiration through the nose a bolus is transported to the lungs. In a randomized cross-over study the effect of two different patterns of breathing, nasal breathing and mouth breathing, was evaluated in 10 patients (mean age 65 years), breathing room air the morning of the first post-operative day after open heart surgery. Nasal breathing is defined as inspiration through the nose and expiration through the mouth, whilst mouth breathing is the converse of this: inspiration through the mouth and expiration through the nose. Pressure in the pulmonary artery and left atrium or pulmonary artery wedge was measured together with thermodilution cardiac output and arterial and mixed venous oxygenation and acid-base parameters. Pulmonary vascular resistance index (PVRI), venous admixture and alveolar-arterial gradient were calculated. Nasal breathing resulted in a lower PVRI, 256 dyn s cm-5 cm-2 vs. 287 (P < 0.01). The oxygen and carbon dioxide tension and pH of arterial and mixed venous blood, venous admixture and the alveolar-arterial gradient remained unchanged. The decreased level of PVRI during nasal breathing compared to that during mouth breathing supports the notion, that endogenous nitric oxide acts as an airborne messenger to modulate the pulmonary vascular tone during normal breathing.