Canadian Journal of Anaesthesia

The most frequently occurring irregularities of the cardiac rhythm during 25 operations on the opened heart were sinus tachycardia, ventricular premature contractions, atrioventricular block, and ventricular tachycardia and fibrillation. Other changes noted in the configuration of the electrocardiogram included flattening and/or disappearance of P waves and flattening of T waves In the majority of the patients, these changes were transient in character, they did not require any drug therapy, and they usually disappeared with temporary interruption or with termination of the surgical procedure. It was considered a good sign if the configuration of the electrocardiogram, after cessation of the cardiopulmonary bypass, was identical or similar to that observed before perfusion. Persistence of the electroencephalographic pattern of a light plane of anaesthesia before, during, and afer perfusion was usually consistent with a good prognosis Reduction, both in potentials and frequency during extracorporeal circulation or after it, usually carried a poor prognosis In all instances, changes in electroencephalographic patterns were noted in all leads, thus indicating equal perfusion of all parts of the brain during extracorporeal circulation We have no explanation as to why electroencephalographic evidence of brain damage developed in four patients postoperatively.

The effect of halothane on myocardial infarction caused by ligation of the left descending coronary artery was studied in rats. The extent of infarction was quantified 48 hours after ligation of the artery by planimetric measurement of left ventricular slices stained with nitrobluetetrazolium. Animals exposed to halothane one per cent for three hours after the coronary ligation were compared with a control group which received halothane for only 5-7 minutes during surgery. It was found that halothane caused a small increase in infarction size (31.3 ± 1.5 per cent of the left ventricle compared to 25.7 ± 2.3 percent, p < 0.05). This effect was accompanied by a decrease in systolic blood pressure (91 ± 2 mmHg compared to 113 ± 3 mm Hg, p < 0.001). Heart rate did not change significantly. Analysis of our results in comparison to previously reported data on the effect of halothane on myocardial ischaemia in different experimental conditions shows that halothane may produce beneficial as well as detrimental effects on ischaemic injury to the myocardium. The latter can result when the drug causes marked hypotension in the absence of a significant decrease in heart rate.

Thở tự phát trong quá trình phẫu thuật nội soi là nguy hiểm và cần phải bị lên án. Cần phải thiết lập thông khí được kiểm soát đầy đủ, đủ để loại bỏ carbon dioxide được bài tiết bởi phổi trong tất cả các trường hợp. Một số biến chứng nghiêm trọng hơn liên quan đến quy trình này đã được thảo luận, vì chúng ảnh hưởng trực tiếp đến việc quản lý gây mê của các bệnh nhân này. Những biến chứng này bao gồm giảm cung lượng tim do trở ngại dòng máu trở về, tắc mạch carbon dioxide, thủng tạng và chảy máu.