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Cephalothin was used as a prophylactic antibiotic in 100 consecutive patients undergoing open-heart surgery. Twenty-eight grammes of cephalothin sodium were given by continuous infusion over 48 h. The incidence of post-operative infections was low and the infections were of late onset. No immune reaction to the drug was observed, and no nephrotoxic effects were seen, despite the relatively high dose schedule and the simultaneous use of frusemide in these patients. We conclude that cephalothin sodium is a safe and effective antibiotic for use during and after open-heart surgery. [ABSTRACT FROM PUBLISHER]

Possible aetiological factors, presentation, and management were reviewed in 18 patients with posterior left ventricular rupture complicating mitral valve replacement seen at one centre over six and a half years. The patients were elderly (mean age 57), predominantly women (16 of the 18), and suffering from mitral stenosis. Rupture was much more common after isolated replacement of the mitral valve (16 out of 797 operations) than after double valve replacement (one out 236) or mitral valve replacement and coronary artery bypass graft (one out of 70). A total of 1221 mitral valve replacements were performed over this period, with an overall incidence of rupture of 1.47%. Damage to the valve annulus occurred five times. On four occasions haemorrhage followed a vigorous response to a bolus dose of an inotrope. With the exception of these features, it was difficult to define specific risk factors. Eleven patients bled while still in theatre; one of them survived long term and another four lived for four to 10 days. Repair after restarting cardiopulmonary bypass made short term survival much more likely. In seven rupture developed after return to the intensive therapy unit; again only one survived long term. In nearly all cases bleeding was at, or just below, the atrioventricular groove. Rupture probably occurs after endocardial damage to a thin myocardium that has lost the internal buttress of the subvalvar apparatus. With the rise in intraventricular pressure at the end of bypass blood dissects into the myocardium, resulting in a large haematoma and eventual rupture. [ABSTRACT FROM AUTHOR]

Thrombotic obstruction is the most feared complication of the Björk-Shiley tilting disc prosthesis. From 1971 to 1982 1186 Björk-Shiley valves were implanted in 900 patients. There were 93 deaths in hospital. Eight hundred and seven patients have been followed for a total of 4146 patient years; 14 patients were lost to follow up. Nineteen cases of thrombotic obstruction were identified at necropsy or at a repeat operation in the study group. The mitral prosthesis was thrombosed in 16 patients, the aortic in two, and the tricuspid in one. The incidence for this complication has been calculated to be 0.46 per 100 patient years for all valve positions, 0.79 for single mitral valve replacements, 0.18 for aortic replacements, and 0.63/100 for the tricuspid position. The maximum possible incidence of this complication in this population has been calculated to be 1.4 per 100 patient years. The mortality rate was 41.7% for reoperation and 63% for the development of the complication. Risk factors that have been identified are inadequate anticoagulant control, poor preoperative exercise capacity, and possibly also the implantation of small prostheses. [ABSTRACT FROM AUTHOR]

Pulsatile perfusion has been shown to offer significant haemodynamic advantages over non-pulsatile perfusion in many experimental studies. Clinical acceptance of pulsatile perfusion during cardiac surgical procedures has, however, been hampered by the lack of technologically satisfactory pulsatile pump systems, and by inadequate clinical experience of routine use of pulsatile perfusion. The recent introduction of reliable pulsatile pump systems with low haemolysis characteristics has made possible the clinical validation of the previous experimental studies. We describe the results of a prospective study of mortality, haemodynamic morbidity, and haematological status, in 350 consecutive adult patients submitted to cardiopulmonary bypass procedures in a surgical unit over a 12-month period. One hundred and seventy five patients were perfused with conventional non-pulsatile flow and 175 with pulsatile flow, using a modified roller-pump pulsatile system (Cobe-Stockert). The groups were closely similar in terms of preoperative characteristics, referral category, and pathology requiring surgery. Operative techniques, bypass parameters, and anaesthetic regime were standardised in both groups. The results were as follows. (1) Total mortality was significantly lower in the pulsatile group (4.6%) compared with the non-pulsatile group (10.3%), p = 0.06. (2) The incidence of deaths attributable to post-perfusion low cardiac output was significantly lower in the pulsatile group (1.1% compared with 6.3%, p = 0.02). (3) Requirement for mechanical (intra-aortic balloon) or drug circulatory support was significantly lower in the pulsatile group. (4) The use of pulsatile perfusion was not associated with any increase in haemolysis, blood cell depletion, or postoperative bleeding problems. [ABSTRACT FROM AUTHOR]

The effects of pulsatile and non-pulsatile cardiopulmonary bypass (CPB) on levels of peripheral vascular resistance and plasma angiotensin II (AII) have been studied in 24 patients submitted to elective cardiac surgical procedures. Twelve patients had conventional non-pulsatile perfusion throughout the period of CPB (non-pulsatile group), while 12 had pulsatile perfusion during the central period of total CPB, using the Stockert pulsatile pump system (pulsatile group). There were no significant differences between the groups in respect of age, weight, bypass time, cross-clamp time, or in mean pump flow or mean perfusion pressure at the onset of CPB. Peripheral vascular resistance index (PVRI) and plasma AII levels were measured at the onset of total CPB and at the end of total CPB. In the non-pulsatile group PVRI rose from 19.6 units to 29.96 units during perfusion. In the pulsatile group PVRI showed little change from 20.89 units to 21.45 units during perfusion (P less than 0.001). Plasma AII levels (normal less than 35 pg/ml) rose during perfusion from 49 pg/ml to 226 pg/ml in the non-pulsatile group. The rise in the pulsatile group from 44 pg/ml to 98 pg/ml was significantly smaller than that in the non-pulsatile group (P less than 0.01). These results indicate that pulsatile cardiopulmonary bypass prevents the rise in PVRI associated with non-pulsatile perfusion, and that this effect may be achieved by preventing excessive activation of the renin-angiotensin system, thus producing significantly lower plasma concentrations of the vasoconstrictor angiotensin II. [ABSTRACT FROM AUTHOR]

An unusual case of chylothorax is described in a 4-year-old child after repair of a ventricular septal defect and ligation of a patent ductus arteriosus through a median sternotomy. Left chylothorax developed after a latent period of six days and was treated initially with continuous drainage and parenteral supplementation of proteins and lipids. Operative intervention with oversewing of the site of the leak in the anterior mediastinum proved necessary after three weeks. The anatomical variations of the thoracic duct are outlined to explain the occurrence of chylothorax after diverse intrathoracic operations. The physiological effects of a thoracic duct fistula and various aspects of management are reviewed. [ABSTRACT FROM PUBLISHER]

Thirty patients with severe preoperative pulmonary hypertension (pulmonary artery pressure range 90-165 mmHg, mean 118 mmHg) were reviewed following single mitral valve replacement, with prosthetic valves, within the last 10 years (1964-74). The early and late mortality for this group was no different from that of the total series of mitral valve replacements performed over the same period. Marked postoperative clinical improvement was accompanied by corresponding radiological and electrocardiographic changes. In addition there was a statistically highly significant haemodynamic improvement in the 21 survivors (mean survival time 5 1/2 years). At recatheterization the mean pulmonary artery pressure was 41-5%, the mean wedge pressure 46-3%, and the transpulmonary gradient (PAm-LAm) 36-1% of the preoperative values. It is concluded that gross pulmonary hypertension is not per se a contraindication to mitral valve replacement surgery. [ABSTRACT FROM AUTHOR]

Organic disease of the tricuspid valve required surgery in 18% of all patients undergoing valve replacement over a five-year period. Differentiation of organic from functional disease is difficult and may be made only at open-heart surgery. The results of a series of 56 patients who underwent tricuspid valve replacement are presented; of these, 53 had organic disease. Operative mortality at the end of five years had fallen to 7% with significant clinical improvement in 79% of patients, a reduction in cardiothoracic ratio in 81%, and a low incidence of postoperative tricuspid incompetence. [ABSTRACT FROM PUBLISHER]

, , 624-632. A comparison was made of the haemolytic complications in 85 patients with two different types of Starr-Edwards cloth-covered ball and cage prosthesis with those in 44 patients with the Björk-Shiley tilting disc valve. Intravascular haemolysis, as detected by the presence of haemosiderinuria, occurred significantly less often with the Björk-Shiley than with the Starr-Edwards valve, the overall incidence with aortic, mitral or multiple replacements being 31%, 15%, and 20% for Björk-Shiley and 94%, 92%, and 88% for Starr-Edwards valves respectively. There was no significant difference in the frequency of haemolysis between each of the two types of Starr-Edwards prosthesis studied at either the aortic (2300 versus 2310 model) or mitral (6300 versus 6310) site. Haemolytic anaemia developed in only one patient with a Björk-Shiley valve but was common though usually mild with Starr-Edwards prostheses, particularly aortic valve replacements with the 2300 model and in aortic plus mitral (± tricuspid) replacements. The greater severity of haemolysis produced by Starr-Edwards valves, again especially of the latter types, was further demonstrated by higher serum lactate dehydrogenase and 24-hour urinary iron levels. It is concluded that the Björk-Shiley tilting disc valve represents a significant advance in the amelioration of the haemolytic complications of prosthetic valves. [ABSTRACT FROM PUBLISHER]

The Doppler echocardiographic characteristics of 70 prosthetic valves in 35 patients are reported. Twenty nine patients had a Björk-Shiley prosthesis in both mitral and tricuspid positions and six had Carpentier-Edwards valves in both sites. Five of the patients had abnormal tricuspid prostheses on the basis of clinical and echocardiographic criteria. Pulsed wave Doppler echocardiography was used in all examinations. The pressure half times for the normal tricuspid prosthetic valves, 105 (40) ms (Björk-Shiley) and 97 (53) ms (Carpentier-Edwards), were significantly longer than those of normal mitral prosthetic valves, 75 (18) ms (Björk-Shiley) and 83 (15) ms (Carpentier-Edwards). The range of pressure half times for the abnormal tricuspid valves (237-530 ms) was distinct from that of the apparently normal tricuspid prosthetic valves (38-197 ms). There was an increase in the peak velocity of the obstructed tricuspid prosthetic valves (1.69 (0.12) m/s) in comparison with normal prostheses (1.06 (0.26) m/s). The normal range of pressure half times for the Björk-Shiley and Carpentier-Edwards valves in the mitral position is not applicable to the same valves in the tricuspid position. The valve appears to function well with very long pressure half times but a pressure half time of greater than 200 ms coupled with a peak velocity of greater than 1.60 ms without significant valve regurgitation indicates tricuspid obstruction of the tricuspid prosthetic valve. [ABSTRACT FROM PUBLISHER]