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N Odom

Publications and source records attributed to N Odom.

5 recordsLinked to original sources
PubMed1996

A pilot study of blood antioxidant and free radical marker profiles in patients awaiting coronary artery bypass grafting.

Coronary artery bypass grafting (CABG) carries a high risk of acute pancreatitis. We report a pilot study to investigate whether pre-existing oxidative stress might underlie this susceptibility, in that a burst of free radical activity not only accompanies the reperfusion stage of CABG but seems to be a pivotal step in the pathogenesis of pancreatitis. Samples of peripheral venous blood were obtained on the morning of surgery from 8 consecutive patients (age, median and range, 62, 35-70 years) with > 75% stenosis in at least three coronary vessels and a further 8 (64, 49-70 years) who had received 1200 mg allopurinol in divided doses in the previous 48 h: the results were compared with profiles of 8 healthy controls (56, 50-60 years) with normal exercise ECG. None of the patients or controls currently smoked cigarettes and the majority drank alcohol on a social basis. Compared with controls, untreated patients had lower levels of glutathione (P < 0.001) and ascorbate (P < 0.05) in plasma, alpha-tocopherol (vitamin E as molar ratio of cholesterol, P < 0.025 and beta-carotene (P < 0.05) in serum. There was no difference in serum selenium levels, but values in patients and controls were lower than in younger controls from this area (P < 0.02). Samples from the patients contained higher concentrations of lipid peroxides than control samples (P < 0.25) but there was no evidence of excessive isomerisation of linoleic acid or oxidation of ascorbate and erythrocytes showed normal ATP and energy charge with no increase in membrane lipid peroxidisability. Treatment with allopurinol did not alter this pattern, such that the ratio of oxidised to total glutathione in plasma was higher among the 16 patients than 8 controls (P < 0.025). Habitually inadequate intakes are the best explanation for the patients' deficits in aqueous phase antioxidants; prescribed low cholesterol diets would exacerbate any prior insufficiency of lipid-phase antioxidants. Correction of these deficits during the months leading up to surgery should reduce the risk of CABG-induced acute pancreatitis.

Adult↗
PubMed1994

Early and late results following combined coronary bypass surgery and mitral valve replacement.

To study the effect of various perioperative and operative variables, we analysed the results of 66 consecutive patients undergoing mitral valve replacement (MVR) and coronary artery bypass grafting (CABG). The mean age was 61.2 years (34 males and 32 females), the mean follow-up 54.71 +/- 7.8 months. The hospital mortality rate was 7.6% (5/66). New York Heart Association (NYHA) functional class (P < 0.01), left ventricular global wall motion score (increased scores indicating impaired function, P = 0.005) and cross-clamp time (P < 0.05) were associated with hospital mortality. There was no significant relationship of age (certainly up to the age of 70), cause of mitral valve disease, severity of mitral regurgitation, number of grafts, presence of angina, or previous myocardial infarction with hospital mortality. There were eight late deaths, survival at 1, 3 and 5 years was 92.4%, 83.2% and 80.2%, respectively. Although there was a trend for pulmonary vascular resistance (P = 0.15), NYHA class (P = 0.18) and aortic cross-clamp time (P = 0.09) to be associated with late survival, the only factor significantly related to late survival was global wall motion score (P = 0.001), i.e. those with scores of more than 10. Severity of mitral regurgitation and cause of mitral valve disease have been reported as being related to late survival in patients undergoing combined CABG and MVR, but we have found no such relationship. Our results indicate that both hospital and late mortality after this operation are strongly correlated with left ventricular function.

Adult↗
PubMed1992

Transient ultrastructural injury and repair of pulmonary capillaries in transplanted rat lung: effect of preservation and reperfusion.

A donor lung is injured during preservation and is generally thought to be further injured by reperfusion on transplantation. Donor lungs from 15 adult male Lewis rats preserved by flush perfusion with cold Marshall's solution at 4 degrees C were examined by scanning and by quantitative transmission electron microscopy after 2, 4, or 7 h of storage at 4 degrees C and after transplantation (syngeneic) at 4 or 12 h (six animals per time interval). During preservation of the donor lung, capillary morphology changed rapidly. Both endothelial cells and type I pneumonocytes thinned (surface/volume ratio increased by 2 h in both; P less than 0.001). Pericapillary edema developed involving the blood-gas barrier. Basement membrane thickness increased significantly (P less than 0.001). Occasional breakage of the endothelial cell sheet occurred after 4 h of preservation, but even after 7 h of preservation there was no evidence of irreversible cell damage. The lamellar bodies of type II pneumocytes aggregated. Changes increased in severity with increase in preservation time. After transplantation, type I and type II pneumonocytes recovered after 12 h, but it took longer for the endothelial cell morphology to recover. Edema decreased rapidly during the first 4 h, despite the number of adherent neutrophils increasing 3-fold. The pulmonary capillaries of the transplanted lung showed no structural evidence of additional reperfusion injury, indicating a satisfactory method of preservation.

Animals↗