Long and short-term outcomes in patients requiring continuous renal replacement therapy post cardiopulmonary bypass.

OBJECTIVE: The development of acute renal failure following cardiac surgery is a rare but devastating complication with high morbidity and mortality. This study aimed to assess the incidence of acute renal failure necessitating continuous renal replacement therapy (CRRT) in patients who required cardiopulmonary bypass, to determine the factors associated with mortality and to evaluate long-term outcome. METHODS: Patients who underwent cardiac surgery between October 1997 and 2003 and treated with CRRT were included (n=98). Six patients were then excluded (already in established renal failure pre-operatively) and one patient lost to follow-up. A retrospective analysis was carried out. RESULTS: Overall CRRT was used in 2.9% (92/3172). The mean (SD) age of patients was 68 (10) years. Their mean pre-operative creatinine level and duration of cardiopulmonary bypass were 154 (87)micromol/l and 160 (84)min, respectively. Mean duration from surgery to establishment of CRRT was 50 (42)h. Mean creatinine level prior to hospital discharge was 168 (93)micromol/l. Thirty-day mortality was 42%. Significant risk factors for death were complex procedures (odds ratio=9.9), gastro-intestinal complications (OR=7.2), cross-clamp time over 88min (OR=5.9), re-exploration (OR=4.0) and patients age over 75 years (OR=3.3). Actuarial 1 and 5-year survivals (95% CI) were 53 (43, 63) % and 52 (42, 62) %, respectively. Only 2 (2.2%) patients required long term renal support. CONCLUSIONS: Acute renal failure necessitating the use of CRRT is a rare but serious complication post cardiopulmonary bypass. In the long-term, surviving patients are not likely to require further renal support.     

Severe rheumatic mitral stenosis with pericardial effusion causing left ventricular tamponade.

A woman of 38 was admitted for urgent surgery of severe mitral stenosis causing pulmonary oedema. Echocardiography showed a pericardial effusion with apparent distortion and collapse of the left ventricle. Urgent drainage of the effusion before mitral valve surgery led to an improvement in cardiac output with no detectable change in right heart pressures.     

Exploration of xenon as a potential cardiostable sedative: a comparison with propofol after cardiac surgery

Xenon anaesthesia is thought to have minimal haemodynamic side-effects. It is, however, expensive and requires special delivery systems for economic use. In this randomised cross-over study, we: (i) investigated the haemodynamic profile and recovery characteristics of xenon compared with propofol sedation in postoperative cardiac surgery patients, and (ii) evaluated a fully closed breathing system to minimise xenon consumption. We demonstrated a significantly faster recovery from xenon (3 min 11 s) than propofol sedation (25 min 23 s). Relative to propofol, xenon sedation produced no change in heart rate or mean arterial pressure and there were significantly higher mean values for central venous pressure (10.6 vs. 8.9 mmHg), pulmonary artery occlusion pressure (11.2 vs. 9.5 mmHg), mean pulmonary artery pressure (20.1 vs. 18.3 mmHg) and systemic vascular resistance index (2170 vs. 1896 dyn.s.cm-5.m-2). The haemodynamic profile seen with propofol reflected its known vasodilator effects. This was supported by the almost identical left ventricular stroke work indexes seen with both methods of sedation.     

Severe rheumatic mitral stenosis with pericardial effusion causing left ventricular tamponade.

A woman of 38 was admitted for urgent surgery of severe mitral stenosis causing pulmonary oedema. Echocardiography showed a pericardial effusion with apparent distortion and collapse of the left ventricle. Urgent drainage of the effusion before mitral valve surgery led to an improvement in cardiac output with no detectable change in right heart pressures.     

Nicorandil-induced peripheral vasodilatation during cardiopulmonary bypass.

Nicorandil is an antianginal agent with actions at epicardial coronary arteries and arterioles, systemic arterioles, and veins. We report our experience with 7 patients taking oral Nicorandil who had severe vasodilation and hypotension requiring significant vasoconstrictor support after cardiopulmonary bypass. Although the mechanism for this phenomenon remains unknown Nicorandil might be interacting with other factors present during cardiopulmonary bypass, as it has relatively mild hemodynamic effects outside this situation.