Transient abnormal Q waves during exercise electrocardiography.

Myocardial ischaemia during exercise electrocardiography is usually manifested by ST segment depression or elevation. Transient abnormal Q waves are rare, as Q waves indicate an old myocardial infarction. The case of a patient with exercise induced transient abnormal Q waves is reported. The potential mechanisms involved in the development of such an abnormality and its clinical implications are discussed.

Outcome of coronary revascularization in patients on renal dialysis.

Previous retrospective studies showed high periprocedure mortality rate and poor outcome after percutaneous transluminal coronary angioplasty (PTCA) or coronary artery bypass grafting (CABG) among renal dialysis patients. The purpose of this study was to compare mortality and clinical event rates in renal dialysis patients after PTCA or CABG. We identified 252 patients from the Emory Cardiovascular Database who were on dialysis and who received PTCA (122 patients) or CABG (130 patients) at Emory University Hospital and Crawford W. Long Hospital between March 1987 and December 1997. Baseline and angiographic characteristics, in-hospital, and 1-year outcome were compared between the 2 groups. Left main disease and 3-vessel coronary artery disease were significantly more common in the CABG group. There was a higher periprocedure and in-hospital mortality in the CABG group (6.9% vs 1.6%, p = 0.04). Patients in the PTCA group underwent repeat revascularization 11 times more frequently within 1 year (22% vs 2%). At 1 year, mortality was 23% in the PTCA group and 27% in the CABG group, with no statistical difference between the 2 groups. This nonrandomized comparison reveals that PTCA and CABG can be performed in selected renal dialysis patients with an acceptable in-hospital major complication rate; however, 1-year mortality remains high in dialysis patients after coronary revascularization. Therefore, attempts at improving outcome in dialysis patients should focus on the prevention and treatment of coronary artery disease before they require coronary revascularization.

Patient-controlled analgesia and postoperative urinary retention after hysterectomy for benign disease.

BACKGROUND: Because postoperative urinary retention can result in considerable morbidity and the rate of retention after hysterectomy has recently increased at our institutions, we conducted a study to determine risk factors for the disorder. STUDY DESIGN: A cohort of 366 consecutive patients who had undergone uncomplicated abdominal or vaginal hysterectomy for benign disease and who met strict inclusion criteria were studied retrospectively by means of a review of their medical records. Student's t test and multivariate logistic regression analysis were used to assess the effects of operative time, amount of fluid given perioperatively, type and amount of analgesic agent administered postoperatively, age of the patient, performance of a vaginal versus an abdominal hysterectomy, and the postoperative use of patient-controlled analgesia on the rate of postoperative urinary retention in these patients. RESULTS: After adjustment for confounding factors, only the use of patient-controlled analgesia (p = 0.0001) and vaginal hysterectomy (p = 0.0003) were significantly related to postoperative urinary retention. Patients who used patient-controlled analgesia were 5.7 times (95 percent confidence interval, 2.6 to 12.4) more likely to have urinary retention than those given an intramuscular agent. CONCLUSIONS: Urinary retention after hysterectomy might be avoided by administering analgesic agents intramuscularly or inserting a suprapubic cystostomy catheter postoperatively, especially in patients who have undergone a vaginal procedure.

Platelet cytosolic free calcium concentration and parathyroid hormone: changing relationships with haemodialysis in end-stage renal disease.

1. Twelve patients receiving haemodialysis for end-stage renal failure were studied at a single dialysis session. Platelet cytosolic calcium concentration, plasma ionized calcium concentration and serum parathyroid hormone concentration were measured before dialysis, mid-dialysis and 30 min after dialysis. 2. Plasma ionized calcium concentration increased towards dialysate calcium concentrations, falling insignificantly after cessation of dialysis. Serum parathyroid hormone concentration fell by 39% during dialysis, with incomplete recovery afterwards. There was no overall change in platelet cytosolic calcium concentration. 3. Patients were divided into two subgroups: low parathyroid hormone (serum parathyroid hormone concentration less than 10 pmol/l) and high parathyroid hormone (serum parathyroid hormone concentration greater than 10 pmol/l). Before dialysis, values of platelet cytosolic calcium concentration or plasma ionized calcium concentration were not statistically different between the subgroups, but the platelet cytosolic calcium concentration was higher in the high-parathyroid hormone subgroup during and after dialysis. 4. Before haemodialysis there was a linear correlation between plasma ionized calcium concentration and platelet cytosolic calcium concentration, which disappeared during dialysis. In contrast, there was no relationship between serum parathyroid hormone concentration and platelet cytosolic calcium concentration before dialysis, but after dialysis a hyperbolic relationship was evident. 5. These results suggest that uraemic toxins may interfere with cytosolic calcium homoeostasis, allowing passive diffusion of extracellular calcium to influence the resting concentration, and that this effect is reversible by haemodialysis.