Postoperative cardiac surgical care: an alternative approach

Combined appropriate anaesthetic and surgical techniques have allowed increasing numbers of patients to be successfully managed in a general surgical recovery ward after cardiac surgery rather than in an intensive care unit. From 1983 to 1989, 933 of 1542 patients undergoing open heart surgery were transferred to the general surgical recovery ward in the immediate postoperative period. Of these, 718 (77%) had undergone coronary artery bypass grafts, sometimes combined with other procedures and 168 (18%) had had cardiac valve replacements with or without other procedures. The remaining 47 (5%) had had miscellaneous cardiac operations. Significant cardiac complications occurred in 29 (3%) patients. The 24 hour chest radiograph was reported as abnormal (mainly atelectasis and effusion) in 63% of patients. Most resolved spontaneously or with physiotherapy. Twenty nine (3%) patients were re-explored to achieve haemostasis. There were no deaths in the general surgical recovery ward. Thirty seven (4%) patients had to be transferred to the intensive care unit for various reasons. The remaining 896 patients were transferred to the general ward after one night (871 patients) or two nights (25 patients) in the general surgical recovery ward. The average duration of stay in hospital for these patients was 9·3 days. Because of the overall success of such management and the low rate of complications over 80% of patients are now managed in the general surgical recovery ward after open heart surgery. The resulting savings in capital expenditure of equipment, medical, nursing, and technical personnel are substantial, and there are major implications for the planning of new cardiothoracic units.     

Patterns of 8-hydroxydeoxyguanosine formation in DNA and indications of oxidative stress in rat and human pleural mesothelial cells after exposure to crocidolite asbestos

Oxidative damage is a proposed mechanism of asbestos-induced carcinogenesis, but the detection of oxidative DNA lesions in target cells of asbestos-induced mesothelioma has not been examined. In studies here, DNA was isolated from both rat pleural mesothelial (RPM) cells and a human mesothelial cell line (MET5A) after exposure in vitro to crocidolite asbestos at various concentrations. DNA was then examined for formation of 8-hydroxydeoxyguanosine (8-OHdG) at 24, 48 and 72 h using HPLC with electrochemical detection. In addition, steady- state mRNA levels of manganese-containing superoxide dismutase (MnSOD) were assessed as an indication of oxidative stress. Whereas RPM cells showed dose-dependent and significant increases in 8-OHdG formation in response to crocidolite asbestos or iron-chelated crocidolite fibers (but not after exposure to glass beads), MET5A cells showed decreases in 8-OHdG. Both cell types exhibited elevations in message levels of MnSOD. In comparison with human MET5A cells, RPM cells exhibited increased cytotoxicity and apoptosis in response to asbestos, as documented by cell viability assays and flow cytometry analysis using propidium iodide. Results in RPM cells indicate that asbestos causes oxidative damage that may result in potentially mutagenic lesions in DNA and/or apoptosis, despite compensatory increases in expression of an antioxidant enzyme.      

Blue toe syndrome: treatment with percutaneous atherectomy

"Blue toe syndrome" refers to digital ischemia of the foot in the presence of palpable or Doppler audible pedal pulses. This clinical syndrome is caused by microembolization to small vessels from a proximal source. The use of percutaneous transluminal atherectomy is described in the treatment of embologenic superficial femoral artery lesions in seven patients. All seven had prompt healing of the ischemic toes, and none required surgical revascularization or amputation. One patient developed a recurrent stenosis at the atherectomy site and had a second episode of digital ischemia, which was treated by means of atherectomy with a larger device. Histologic study of atherectomy specimens suggests that emboli arise from adherent fibrinoplatelet aggregates or thrombus and less often from cholesterol-rich atheromatous plaque. Although either percutaneous transluminal angioplasty or atherectomy can be used to treat the underlying stenosis, percutaneous atherectomy offers the advantage of nonsurgical removal of embologenic material and provides material for histologic study. Percutaneous atherectomy is an effective method of treating embologenic superficial femoral stenoses in patients with ipsilateral blue toe syndrome.     

Dietary administration of an extract from rosemary leaves enhances the liver microsomal metabolism of endogenous estrogens and decreases their uterotropic action in CD-1 mice

We evaluated the effects of a methanol extract from the leaves of the plant Rosmarinus officinalis L. (rosemary) on the metabolism and action of estradiol and estrone. Treatment of female CD-1 mice with 2% rosemary in AIN-76A diet for 3 weeks increased the liver microsomal 2- hydroxylation of estradiol and estrone by approximately 150%, increased their 6-hydroxylation by approximately 30% and inhibited the 16alpha- hydroxylation of estradiol by approximately 50%. Treatment of female CD- 1 mice with 2% rosemary diet for 3 weeks also stimulated the liver microsomal glucuronidation of estradiol and estrone by 54-67% and 37- 56%, respectively. In additional studies, feeding 2% rosemary diet to ovariectomized CD-1 mice for 3 weeks inhibited the uterotropic action of estradiol and estrone by 35-50% compared with animals fed a control diet. The results of this study showed that feeding female mice a 2% rosemary diet increased the liver microsomal oxidation and glucuronidation of estradiol and estrone and inhibited their uterotropic action.