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P A DeValeria

Publications and source records attributed to P A DeValeria.

5 recordsLinked to original sources
PubMed1993

Complement inhibition with soluble complement receptor type 1 in cardiopulmonary bypass.

Although complement activation during cardiopulmonary bypass (CPB) is well documented, its pathogenic role in postperfusion organ injury is unproven. In this study, soluble human complement receptor type 1 (sCR1), a potent inhibitor of complement activation, was used to determine the contribution of complement activation to pulmonary injury in a porcine model of CPB. In vitro experiments demonstrated that sCR1 inhibits both classic and alternative complement pathways in the pig. Seven control piglets and 6 piglets treated with sCR1 (12 mg/kg intravenously) underwent 2 hours of hypothermic (28 degrees C) CPB followed by 2 hours of observation. In control piglets, total hemolytic complement activity and functional activities of C3 and C5 declined to 61.3%, 67.8%, and 61.4% of prebypass values, respectively, after 2 hours of CPB. Plasma from animals treated with sCR1 had virtually no hemolytic activity (total hemolytic complement activity < 5% of baseline), demonstrating effective complement inhibition. Similar degrees of neutropenia developed in the two groups during CPB, and there was no difference in post-CPB lung tissue myeloperoxidase level. Two hours after CPB, pulmonary vascular resistance increased 338% in control piglets but only 147% in piglets pretreated with sCR1 (p < 0.05); the alveolar-arterial gradient was not significantly different between controls (331 +/- 52 mm Hg) and piglets receiving sCR1 (290 +/- 85 mm Hg). Histologic examination revealed similar degrees of pulmonary edema in both groups. These data constitute direct evidence that complement activation plays a pathogenic role in lung injury after CPB.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1991

Current indications, risks, and outcome after pericardiectomy.

A retrospective analysis of the records of 60 patients who underwent pericardiectomy over a 10-year period (1980 to 1990) at The Johns Hopkins Hospital was performed. Indications for operation were effusive disease in 24 patients and constriction in 36 patients. Six patients (10%) with pericardial effusion had pain as the primary symptom necessitating intervention. The operative approach for pericardiectomy was median sternotomy in 52 patients (4 patients required cardiopulmonary bypass) and left anterior thoracotomy in 8 patients. Nine patients (5 with constriction and 4 with effusion) with a prior limited pericardial procedure required formal pericardiectomy. The operative mortality rate for pericardial effusion and constriction was 4.2% and 5.6%, respectively. Follow-up (median follow-up, 56.9 +/- 38.2 months) was obtained on 56 patients (93.3%). Actuarial survival at 1 year, 5 years, and 10 years for all patients was 82.1% +/- 5.1%, 71.7% +/- 6.7%, and 59.8% +/- 12.2%, respectively. A Cox proportional hazards regression analysis was performed using 20 clinical variables. A history of malignancy, previous pericardial procedure, and preoperative New York Heart Association class IV were found to be predictors of poor survival. All patients who underwent operation primarily for effusion with associated pain are alive and have improved functional capacity without steroid use. We conclude that pericardiectomy can be performed with low mortality and can result in good long-term survival and improved functional capacity. Patients who are seen primarily with pain refractory to steroid therapy can be relieved of symptoms with operation.

Actuarial Analysis↗
PubMed1987

Combined heart-lung transplantation in the rat. Comparison of thoracic and abdominal operation techniques.

Recently, we developed two techniques for the combined transplantation of heart and the left lung into the left hemithorax of rats. One technique, with two vessel anastomoses, comprised the microsurgical repair of aorta, anterior vena cava, and left main bronchus. With the other, single vessel technique, only the aorta and bronchus were anastomosed. In this study, we determined the function and histology of syngeneic and cyclosporine (CsA)-treated allogeneic grafts transplanted with both techniques, and compared the results with those of heterotopic heart-lung grafts transplanted with a previously described technique for transplantation into the rat's abdomen. The survival rate of rats operated with either of the thoracic transplantation techniques was high (83%). Lungs and hearts of the grafts functioned well for over two months and had normal morphology when the double vessel technique was used. With the single vessel technique, the function of the lungs started to deteriorate from the third postoperative week onward, probably secondary to congestion. The results of thoracic grafts were superior to those of abdominal transplants, where the nonventilated lungs--especially during immunosuppression--were frequently infected. We conclude that these new techniques for thoracic transplantation are most suitable for research of combined heart-lung transplantation.

Abdomen↗
PubMedDate not supplied

Twelve-hour cardiopulmonary preservation using donor core cooling, leukocyte depletion, and liposomal superoxide dismutase.

Because leukocytes and oxygen radical species contribute to ischemic and reperfusion injury during organ preservation, we examined the effects of a long-acting liposomal superoxide dismutase (liposomal SOD) and mechanical filtration of leukocytes on cardiopulmonary graft function after 12 hours of static preservation. Bovine heart-lung blocks were harvested, core cooled to 15 degrees C, stored in 4 degrees C donor blood for 12 hours, and then orthotopically transplanted (control group, n = 6). In the leukocyte-depletion group (n = 6), a leukocyte filter was incorporated in the bypass circuits of the donor and recipient. In the SOD group (n = 6), liposomal SOD (5000 U/kg) was administered in the cardioplegic solution, in the prime of the bypass circuits of donor and recipient, and immediately before recipient heart-lung reperfusion. In the combination group (n = 6), both leukocyte depletion (LD) and liposomal SOD were used. Only four of six control animals survived more than 2 hours after weaning from bypass, whereas all LD, SOD, and LD + SOD animals survived to be studied at 6 hours. Pulmonary function was assessed at 6 hours by arterial oxygen tension on 100% inspired oxygen (PO2), pulmonary vascular resistance (PVR), and postmortem wet/dry lung weight ratios. Arterial pO2 values (mm Hg) were as follows: control, 102 +/- 51; LD, 437 +/- 60*; SOD, 278 +/- 83; and LD + SOD, 504 +/- 54* (*p less than 0.05 vs controls). PVR values (dynes . sec . cm5) were as follows: control, 1975 +/- 697; LD, 682 +/- 131*; SOD, 607 +/- 191*; and LD + SOD 367 +/- 87* (*p less than 0.05 vs controls).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗