M.V. Braimbridge

Thoracoscopic debridement and pleural irrigation in the management of empyema thoracis

As a sequel to a paper reporting good results obtained in 12 patients with empyema thoracis treated by thoracoscopic debridement and irrigation in our department, subsequent experience with a further 18 patients is reported. Drainage of pus and irrigation resulted in resolution of pyrexia with improvement in general condition in all patients. Overall, complete resolution was obtained by this technique alone in 60% (18/30). Of the 12 patients in whom complete resolution was not obtained, secondary surgical measures resulted in resolution of empyema in 8. Four patients died; all were elderly and severely debilitated, 3 with advanced malignancy. Their deaths were not related to the technique, which was well tolerated in all cases. Thoracoscopic debridement and irrigation used routinely as a first-line measure in empyema thoracis is a safe and relatively atraumatic procedure, does not exclude the use of any subsequent surgical measure, and provides valuable time to improve the condition of debilitated patients so that they may tolerate more aggressive surgical procedures.

The Management of Empyema Thoracis by Thoracoscopy and Irrigation

A technique of irrigation for the management of empyema is described. Initial thoracoscopy under general anesthesia enabled full debridement and division of loculi within the empyema cavity under direct vision. Irrigation with two tubes was instituted until three consecutive cultures of irrigation fluid became sterile; then the chest drains were removed. The results in 12 patients are presented. Using this method, irrigation was required for an average of 14 days and chest drains were removed after an average of 20 days. Patients remained in the hospital for an average of 4.8 weeks. Tuberculous empyema was not found to be a contraindication to the irrigation technique.

Reperfusion-induced arrhythmias in the conscious rat: A comparative study with three calcium antagonists

The effects of three calcium antagonists (diltiazem, verapamil, and nifedipine) on reperfusion-induced arrhythmias were compared in a conscious rat preparation with coronary artery occlusion and implanted electrocardiogram limb electrodes. Upon reperfusion after a 5-min period of occlusion, all (15/15) untreated control rats exhibited immediate ventricular tachycardia, which rapidly deteriorated to ventricular fibrillation; 87% (13/15) of the rats died as a consequence of these rhythm disturbances. In the groups treated with calcium antagonists, each drug (diltiazem, verapamil, or nifedipine) was given as an intravenous bolus 10 min prior to coronary occlusion (n = 12 in each group). The incidence of ventricular fibrillation was significantly reduced by all three calcium antagonists and this antifibrillatory effect resulted in a significantly lower mortality in all drug-treated groups. With diltiazem (0.5 and 2.0 mg/kg) mortality fell from 87 to 42% (P less than 0.05) and 35% (P less than 0.01), respectively; with verapamil (0.5 and 5.0 mg/kg) it fell to 25% (P less than 0.01) and 0% (P less than 0.001); and with nifedipine (5.0 and 50 micrograms/kg), it fell to 25% (P less than 0.01) and 8% (P less than 0.001). At a dose of 5.0 mg/kg, verapamil caused a large reduction in heart rate both prior to and during coronary occlusion and reperfusion; however, with other doses and drugs no significant changes in heart rate were observed. ST segment elevation during the 5-min ischemic period was reduced by pretreatment with all drugs. In conclusion, in the conscious rat, pretreatment with diltiazem, verapamil, or nifedipine affords some protection against reperfusion-induced arrhythmias.(ABSTRACT TRUNCATED AT 250 WORDS)

The Effect of Ionized Calcium, pH, and Temperature on Bioactive Parathyroid Hormone during and after Open-Heart Operations

Normal myocardial function is dependent on the metabolic balance of a number of electrolytes and hormones. The calcium ion plays a major role in muscle contraction and is rigorously controlled within narrow limits. Open-heart surgery imposes metabolic disturbances on both electrolytes and hormones, especially ionized calcium. Normally, ionized calcium levels are controlled by parathyroid hormone with a negative feedback from the ionized calcium controlling the system, but the results from this study suggest that during open-heart procedures, ionized calcium does not impose its normal negative feedback on bioactive parathyroid hormone secretion. The low blood pH levels that occurred during the operative conditions of the patients studied and the level of hypothermia imposed on the circulating blood during cardiopulmonary bypass appeared to influence the control of parathyroid hormone secretion, causing high levels of hormone to be secreted during this period.

Cardioplegia with an extracellular formulation

The clinical use of cardioplegia is now accepted world-wide for all aspects of cardiac surgery. Myocardial protection can be achieved with a number of cardioplegic solutions but, essentially, there are only two types of solution — the ‘extracellular-type’ and the ‘intracellular-type’. The latter has been covered in the preceding chapter.

Cytochemical Analysis of Left Ventricular Biopsies in Open-Heart Surgery: A Pilot Study

Summary 1. In previous studies three histochemical tests have been useful in detecting myocardial dysfunction. 2. These have been applied to left ventricular biopsies from 37 patients who underwent prolonged open-heart surgery. The immediate objective was to investigate whether these tests could be used as a guide to prognosis. 3. There was good correlation between the graded response to the histochemical tests and the clinical assessment of the myocardium. The tests over-warned in 3 cases out of 15, and did not warn of myocardial dysfunction in 2 cases out of 22 which showed clinical dysfunction. 4. One of the most difficult aspects of the pre-operative assessment of left heart lesions is the evaluation of the state of the myocardium. The development of cardiac biopsy methods that can be performed at the time of catheterisation would allow such histochemical analyses of myocardial function to be more widely used.

The international cardiothoracic surgeon

Our honored speaker, I believe, wants to say something about Dr Sloan, so 1 shall only mention that we all are aware and in awe of the tremendous contributions he has made to thoracic surgery at the University of Michigan, at the American Board of Thoracic Surgery, and as Editor of The Annals of Thoracic Surgery, as well as all of the service that he has given both to the American Association for Thoracic Surgery and The Society of Thoracic Surgeons. And 1 would ask Dr Sloan to stand and be recognized. (Applause.) Our honored guest today to give the Sloan Lecture is M r Mark Braimbridge, who 1 am pleased to announce was just made an honorary member of this Society. He will speak today on the International Cardiothoracic Surgeon, and because of that he has asked that 1 not give you dates and details of his illustrious career because that will be part of his talk. 1 will say, however, that he was born in London, almost by mistake, because his father was a surgeon in Kenya, East Africa, and was home on leave when Mark was born. He and the family returned, however, to Kenya in the Nairobi area, where he grew up. He was in World War 11 from the beginning, serving in the artillery in the British army, both in East Africa and in India from 1939 to 1945. He then went to London, where he qualified for the equivalent of our M D , and we met in Palo Alto in 1956 and 1957 when he was doing a fellowship with Dr Frank Gerbode in San Francisco. W e became good friends, and we were reminiscing last night about the wonderful experiences and fun that we had together. Mark then returned to London, where he has remained to this day. He had residencies at the Hammersmith Hospital, at the Brompton Chest Hospital, and at the London Chest Hospital, working under such giants as M r Cleland, Lord Brock, Sir Thomas Holmes, and many others. In 1963 he was appointed Consultant to the National Health Service at St. Thomas Hospital, where he became head of the heart surgery team until his retirement last year. His main research projects have been in myocardial protection, advocating a cellular approach with biopsies at a time when the international focus was on physiological Sarnoff curves. His research also was in mitral valve repair, bacterial endocarditis, esophagobronchial fistula, empyema management, and the financial implications of cardiothoracic surgery. He retired last year from surgery, but knowing Mark as well as 1 do, 1 know he won’t retire from life. 1 found out last night from Elizabeth that he has a graduate degree now in English literature, and 1 quizzed him on Shakespeare all the way home, 1 might add. Without further ado 1 would like to present our new honorary member of this Society, M r Mark Braimbridge, who will deliver the Herbert Sloan Lecture.

Variations in the amount and distribution of phosphorylated compounds in ischemia and reactive hyperemia in the dog heart

Abstract A study has been made of the concentration and location of phosphorylated compounds in serial myocardial biopsies taken from the left ventricle of dogs during and after brief coronary occlusion. Ischemia reduced the amount of phosphorylated substances, such as ATP and phosphocreatine. During reactive hyperemia these substances were lost into the intimate coronary circulation around the fibers. This raises the possibility that the leakage of such vasodilator substances from the myocardium into the vascular bed, either themselves or through their hydrolytic products, may account for the vasodilation of reactive hyperemia.