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D K Cooper

Publications and source records attributed to D K Cooper.

334 records · Page 19Linked to original sources
PubMedDate not supplied

Is pulmonary ischemia a factor in the reperfusion response? An experimental study in the chacma baboon.

A reimplantation or reperfusion response has been described in both the experimental animal and the human patient after various procedures involving pulmonary ischemia. We have investigated this phenomenon in a primate model. Ten chacma baboons were placed on cardiopulmonary bypass and cooled to 20 degrees C. Circumferential segments of the right main bronchus and pulmonary artery were denuded of all surrounding tissue. Each structure was then cross-clamped, which rendered the lung ischemic, during which time the organ was immersed in cold saline solution. Ischemia was maintained for 1.5 to 5 hours; after reperfusion and discontinuation of bypass, the right lung was biopsied and the chest closed. Chest radiographs, lung biopsies, and arterial blood gases were taken at intervals for up to 16 to 28 days. Right lung shadowing on chest radiography with concomitant histopathologic changes, indicative of a reperfusion reaction, were seen in only one animal, which had undergone lung ischemia for 1.5 hours. In one other animal that was ischemic for 5 hours, patchy opacification of the lung was seen on two occasions (days 8 and 15) with concomitant mild histopathologic changes. In conclusion, therefore, a major reperfusion response after pulmonary ischemia in the chacma baboon is possible but unusual. This would suggest that the appearance of pulmonary opacification on chest radiography within the first 4 weeks after heart-lung transplantation in humans is most likely attributable to some other condition, such as isolated lung rejection or infection.

Animals↗
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Does the electrocardiogram detect early acute heart rejection.

Changes in electrocardiographic parameters, particularly a reduction of the voltage of the QRS complex, have been held to indicate acute rejection of a transplanted heart. In a series of heterotopic heart recipients, changes in electrocardiographic parameters were correlated with histopathological evidence of acute rejection seen on endomyocardial biopsies obtained by the percutaneous transvenous technique. No statistically significant correlation was found between the electrocardiographic changes and the histopathological features. The electrocardiogram appears to be an unreliable predictor of early acute rejection in patients with heterotopic heart transplants.

Adolescent↗
PubMedDate not supplied

The value of recipient heart assistance during severe acute rejection following heterotopic cardiac transplantation.

Acute rejection remains a major complication of cardiac transplantation. One of the advantages of heterotopic as opposed to orthotopic heart transplantation is that the recipient heart remains in situ, and may provide valuable support for the circulation if donor heart function is severely reduced during an acute rejection episode. Details are presented of 11 patients who underwent acute rejection severe enough to cause loss of significant function of the donor heart, during which time life was maintained by the patient's own diseased heart. In 5 cases the acute rejection proved reversible, with patient survival extending from 10 weeks to 61/2 years, though only 2 remain alive today. In 6 cases rejection was irreversible; 4 of these patients underwent a second heart transplant, but only 1 remains alive today.

Adult↗
PubMedDate not supplied

A comparison of two prophylactic antibiotic regimes for open-heart surgery.

Two groups of patients undergoing open-heart surgery were given prophylactic courses of antibiotic lasting five days. One group (61 patients) received a cephalosporin and the second (57 patients) received a combination of penicillin, flucloxacillin and streptomycin. The overall major infection rate was low (3--4%), particularly so in the cephalosporin group (1.6%). There was no increased nephrotoxic effectt of the cephalosporin, and any nephrotoxic effect that was present was temporary and clinically unimportant. The major infecting organism in both groups was Staphylococcus albus (Staph. epidermidis). The efficiency, therefore, of any prophylactic regime which omits gentamicin, to which Staph. albus in usually sensitive, remains in doubt.

Adult↗
PubMedDate not supplied

Study of the relative incidences of psychosocial factors before and after heart transplantation and the influence of posttransplantation psychosocial factors on heart transplantation outcome.

Psychosocial factors substance abuse, noncompliance, psychiatric problems, and obesity in relation to the outcome of heart transplantation have been investigated. Data were gathered at the time of initial assessment, and patients (n = 53) were monitored during the follow-up after heart transplantation (mean 18 months). Noncompliance, psychiatric problems, or excessive weight before heart transplantation continued after heart transplantation. Significantly fewer substance abusers exhibited similar behavior after heart transplantation (p < 0.01), although in many cases this exposed other psychiatric or compliance problems. Patients with psychiatric problems after heart transplantation had a higher risk of infection (p < 0.01). Both these patients and those who were noncompliant had higher incidences of hospital readmission (p < 0.01) which were reflected in higher medical costs (p < 0.01) during the second year after heart transplantation in both subgroups. We conclude that (1) heart transplant recipients do not alter previous behavior after heart transplantation except with regard to substance abuse, (2) patients exhibiting substance abuse before heart transplantation and abstaining after heart transplantation have other psychosocial problems, (3) psychosocial problems after heart transplantation do not increase the risk for medical complications in the early posttransplantation period except with regard to infection, and (4) the presence of noncompliance and psychiatric problems after heart transplantation is related to increased readmissions and higher total medical costs.

Age Factors↗
PubMedDate not supplied

Returning to work after heart transplantation.

The purpose of this study was to determine what factors influence a patient's return to work after heart transplantation. Two hundred fifty patients who had undergone heart transplantation were surveyed at seven regional centers in the United States (five of which were Medicare-certified). Of these patients, 45% were employed, 36% were unemployed, 13% were medically disabled, and 6% had retired. A stepwise discriminant analysis resulted in the selection of six variables that helped differentiate those patients who did and those who did not return to work after the transplantation. The factors associated with a patient's return to work included (1) self report of being physically able to work, (2) no loss of health insurance, (3) longer length of time after transplantation, (4) education level of more than 12 years, (5) no loss of disability income, and (6) shorter length of disability before heart transplantation. This information could accurately profile 91% of the patients who were employed, 69% of the patients who were unemployed, and 80% for the entire group. The implication of this study is that social rehabilitation is not synonymous with the medical results of heart transplantation. More attention to social rehabilitation is required if heart transplant recipients are to enjoy a better quality of life and become fully productive members of the community.

Adult↗