During the period 1974-1983, 13 857 subclavian or internal jugular vein catheterizations were analysed in the same hospital. The data on the catheterizations have been collected prospectively in the hospital computer. In 93% of the cases, catheterization was subclavian vein cannulation performed through the infraclavicular route. In 15% of the cases the catheter position was not ideal, verified with x-ray; e.g. the catheter tip was turned into the internal jugular vein. Of the catheters 70% were kept in place for less than 7 days, and only 6% for over 2 weeks. More than one catheterization was required in 26% of the cases during the same hospitalization. Recatheterization is an important prophylactic measure for preventing septic complications, if suspicion of infection arises. In 5% of the cases, some complications occurred, but they were mostly minor, such as haematoma at the puncture site. More serious complications were 19 pneumothoraces (0.1%). The results suggest that subclavian vein catheterization is a fairly safe method for large-scale use in a hospital, if only a limited group of physicians perform it. Certain precautions should, however, be taken.

A series of 89 surgical patients (1 11 operations) with preoperative myocardial infarction (MI) was analysed for factors predisposing to the development of a postoperative reinfarction. Six of them suffered postoperative MI, and three of these patients died. In the statistical analysis the following risk factors emerged: age over 60 years, anaemia, hypertension, and the fact that the previous MI had been posterior. Abdominal operations were more dangerous concerning reinfarction than other operations. In the other series of 11 deceased patients with postoperative reinfarction collected from the autopsy material, about the same risk factors were found. The most important factor seemed to be hypotension, which complicated the surgery. All 11 patients had arrhythmias in their preoperative electrocardiogram. Previously treated heart failure was present in five of these patients. Postoperative symptoms analysed in the first series suggest that if a patient with preoperative MI has arrhythmias, hypotension, dyspnoea, diffuse unlocalized pain or chest pain after sugery, he is very likely to have a reinfarction.

The abrupt cessation of clonidine therapy can induce a withdrawal syndrome. This may also appear immediately after anaesthesia if clonidine medication is discontinued during the operation day. We studied (1) whether the withdrawal syndrome occurs postoperatively as often as otherwise when clonidine therapy is discontinued, and (2) the action of this clonidine withdrawal on the circulation as compared to patients who received clonidine without interruption during the operation day. During the recovery period in 2 out of 10 patients in whom clonidine medication was discontinued, a hypertensive crisis occurred, which was relieved by clonidine readministration. Clonidine given with premedication eliminated high rises in blood pressure during anaesthesia. During the recovery period, the regular intramuscular administration of the same dose of clonidine as the patients had used orally decreased blood pressure to almost normotensive levels. The slightly increased urinary catecholamine excretion and plasma renin activity in these patients might, however, indicate that the circulatory homeostasis was disturbed in some degree. The results suggest that it is important to give clonidine continuously, even during the operation day. The dose may be the same as, or preferably somewhat smaller than that which the patients have previously received orally.

A series of 89 surgical patients (111 operations) with preoperative myocardial infarction (MI) was analysed for factors predisposing to the development of a postoperative reinfarction. Six of them suffered postoperative MI, and three of these patients died. In the statistical analysis the following risk factors emerged: age over 60 years, anaemia, hypertension, and the fact that the previous MI had been posterior. Abdominal operations were more dangerous concerning reinfarction than other operations. In the other series of 11 deceased patients with postoperative reinfarction collected from the autopsy material, about the same risk factors were found. The most important factor seemed to be hypotension, which complicated the surgery. All 11 patients had arrhythmias in their preoperative electrocardiogram. Previously treated heart failure was present in five of these patients. Postoperative symptoms analysed in the first series suggest that if a patient with preoperative MI has arrhythmias, hypotension, dyspnoea, diffuse unlocalized pain or chest pain after surgery, he is very likely to have a reinfarction.

No abstract