Search PubMed⌕ Search

Biomedical subjects

G Lemole

Publications and source records attributed to G Lemole.

14 recordsLinked to original sources
PubMed1989

Simultaneous use of microfibrillar collagen hemostat and blood saving devices in a canine kidney perfusion model.

Intraoperative autotransfusion and topical microfibrillar collagen hemostats have been increasingly used, often simultaneously, in various surgical procedures to minimize intraoperative blood loss and thus reduce the inherent risks of homologous blood transfusion. As moderate amounts of small particles have been shown to pass through filtering devices during intraoperative autotransfusion, concern has been raised over the amount of heterologous collagen fibrils transfused and their effect on the host. We found that 2% of microfibrillar collagen hemostat particles pass through the 20-microns millipore filter contained in the tested autotransfusion device (William Harvey H-4700 cardiotomy reservoir). Using a canine kidney perfusion model, we found multifocal perivascular inflammatory reactions within the renal parenchyma five days after transfusion of filtered autologous blood containing minute amounts of microfibrillar collagen hemostat. The findings demonstrate a strong inflammatory foreign body response to heterologous collagen particles trapped in the microcirculation of the perfused kidneys. It is concluded that despite using filters with a pore size of 20 microns, using intraoperative autotransfusion and microfibrillar collagen hemostats simultaneously creates a potential risk because adverse reactions can be elicited especially within the microvasculature of tissues containing end-arterial circulation.

Animals↗
PubMed1987

Improved survival with coronary bypass surgery in patients with three-vessel coronary disease and abnormal left ventricular function. Matched case-control study in patients with potentially operable disease.

Recent studies have suggested that patients with three-vessel coronary disease and abnormal left ventricular function have better survival rates with bypass surgery than with medical therapy alone. Case-control studies may give accurate survival estimates, but to be valid, selection biases must be taken into account. A matched case-control method was used to compare survival patterns in patients treated medically or surgically during the 1980s. Fifty medical patients with potentially operable coronary disease and 46 surgical patients were matched for significant three-vessel disease and abnormal ventricular function. These two groups had no significant differences with regard to 24 variables, including age (64 +/- 8 versus 63 +/- 10 years), chest pain class, congestive heart failure signs, ejection fraction (36 +/- 8 versus 37 +/- 9 percent), segmental wall score, or a coronary score evaluating lesion site and severity. There were slight differences between the two groups with regard to congestive heart failure symptoms (p = 0.04). Patients undergoing bypass surgery had improved four-year survival rates compared with the medical group (89 versus 55 percent; p = 0.01). Thus, this study used an effective case-control method to suggest that, in the 1980s, coronary surgery improves prognosis substantially in surgically approachable patients with severe coronary disease and ventricular dysfunction.

Aged↗
PubMed1985

The effect of ventilation on systemic blood gases in the presence of left ventricular ejection during cardiopulmonary bypass.

The effect of pulmonary ventilation upon systemic arterial blood gases during cardiopulmonary bypass in the presence of left ventricular ejection was evaluated in 20 adult male patients undergoing coronary artery bypass grafting. Following rewarming, establishment of a sinus rhythm, and production of a pulse pressure of at least 20 mm Hg on the arterial pressure trace caused by left ventricular ejection, arterial blood gases were obtained from the arterial and venous extracorporeal circuits and the radial arterial cannula. Patients were then randomly assigned to a nonventilation (n = 10) or a ventilation (n = 10) group. The ventilation group was given 10 breaths/min with 100% oxygen at a tidal volume of 10 ml/kg. Whereas the nonventilation group received apneic oxygenation at zero end-expiratory pressure. After 5 minutes the arterial blood gas data were again obtained. Significant findings (p less than 0.05) included decreases in systemic carbon dioxide tension and increases in systemic pH in the ventilation group and decreases in systemic oxygen tension in the nonventilation group. Although the changes in the arterial blood gases were significant, these changes occurred well within the limits of clinical acceptability. It is concluded that left ventricular ejection for short periods during full cardiopulmonary bypass does not necessitate pulmonary ventilation.

Aged↗
PubMed1981

Ventricular function before and after mitral valve replacement.

To evaluate right ventricular function following mitral valve replacement, we studied 84 patients with isolated mitral valve disease with the use of first-pass radionuclide angiography before, 1 week after, and up to 1 year after operation. The right ventricular ejection fraction for the entire group improved from 29% +/- 11% to 43% +/- 10% (p less than 0.001) at 1 week. This increase was maintained at 3 months (41% +/- 10%) and up to year after operation (40% +/- 12%). The improvement was found not to be influenced by either the type of valvular lesion or the presence and/or level of pulmonary hypertension. When the patients were grouped according to the type of prosthetic valve placed at operation, the right ventricular ejection fraction increased in all patients within 1 week of operation, with sustained improvement at 3 months postoperatively. Thereafter, it began to decline in patients receiving a Carpentier bioprosthesis while being maintained in those patients who received disc valves. Further analysis revealed that those patients who receiving the larger Carpentier bioprostheses had a greater deterioration of right ventricular function than those receiving the smaller Carpentier valves. Left ventricular function in the entire group was normal preoperatively (62% +/- 16%) and was unchanged at 1 week (60% +/- 16%) and a 1 year (59% +/- 16%) after operation.

Adult↗
PubMed1976

Results of mitral valve replacement with the Beall prosthesis in 209 patients.

In this 3 year study of 209 patients who underwent mitral valve replacement with the newer Beall prostheses (Models 104 and 105) the operative mortality rate was 5.2 per cent. None of these deaths was related to the valve. This prosthesis features a larger frustrum area and a "turtle-neck" sewing ring which permits its rapid insertion with a continuous suture technique. Of the 20 (9.5 per cent) late deaths, two were due to thrombosis of the valve. Among the 178 survivors, 17 developed thromboembolic complications; however, 10 of these patients recovered. Late clinical results have been quite satisfactory in over 90 per cent of the survivors. In the 15 patients who underwent hemodynamic studies postoperatively, the cardiac index and pulmonary artery pressure showed significant improvement; however, they still had transvalvular gradients at rest. The improvement in the design of this prosthesis has been an important factor in lowering the operative risk and improving the late results of mitral valve replacement.

Adult↗
PubMed1975

Preliminary experience with the use of a programmable pacemaker.

One hundred sixty-four patients, in whom new externally programmable pacemakers had been inserted, were studied over a two year period, beginning July, 1972. Following implantation, the rate and current output of this pacemaker could be changed at any time by a non-invasive technique involving electromagnetic pulse trains emitted by an external "programmer". In 89 percent of the patients it was possible to reduce battery output by half, implying greater longevity of the pacer in these cases. In 15 percent of the patients, manipulative control of the pacemaker rate was employed and found beneficial.

Adult↗
PubMedDate not supplied

New technique for infusion of cardioplegic solution in aortic valve incompetence.

Direct coronary cannulation for induction of cardioplegia in patients with aortic valve incompetence may result in ostial stenosis. In order to circumvent this problem, a technique by which the valve was made competent by suturing the cusps together has been recently applied. Thus, an effective aortic cardioplegic infusion could be accomplished.

Aortic Valve↗