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D Prough

Publications and source records attributed to D Prough.

11 recordsLinked to original sources

Peritonitis after cecal perforation. An experimental model to study the therapeutic role of antibiotics associated with allopurinol and catalase.

This work uses cecal perforation on the rat as a model of intra-abdominal sepsis. Under these conditions, various antibiotics were tested alone or in association with free radical scavengers, such as allopurinol and catalase. It can be concluded that the scavengers were not effective alone, but when combined with antibiotics they rendered good results in the majority of the groups when given postsepsis. Further studies are needed to determine the real role of agents like the free radical scavengers in infectious situations such as the one discussed here.

Allopurinol↗

Effectiveness of high-frequency jet ventilation in management of an experimental bronchopleural fistula.

An animal model was prepared to compare the effectiveness of high-frequency jet ventilation (HFJV) with that of conventional intermittent positive pressure ventilation (IPPV) in managing bronchopleural fistula. In ten adult beagles, the left upper pulmonary lobe was resected and the left upper lobe bronchus was cannulated to establish a permanent bronchopleural fistula. Apposition of the middle lobe to the chest wall was examined via an open thoracotomy. Fistula leakage was measured with the thoracotomy closed, and chest tube drainage was set at 20 cm H2O. With HFJV, lung apposition was attained at lower peak (8.9 cm H2O) and expiratory (5.7 cm H2O) pressures than with IPPV (21.2 cm H2O Peak pressure and 10.7 cm H2O expiratory pressure). With equivalent arterial blood gases, fistula leakage was 47 per cent higher with IPPV than with HFJV (P less than .001). Each 5 cm of positive end expiratory pressure (PEEP) added increased fistula leakage similarly to both systems. Varying the frequency of HFJV did not alter leakage significantly, but increasing the driving pressure markedly increased leakage. Thus, experimentally, HFJV proved superior to IPPV in the management of bronchopleural fistula. When HFJV is used clinically to manage a bronchopleural fistula, the driving pressure should be kept as low as possible and PEEP should be limited. The ventilatory rate may be varied to achieve the desired PaCO2 without significantly affecting leakage through the fistula.

Animals↗

The 1996 Moyer Award. Effects of endotoxin on the Th1/Th2 response in humans.

Monocyte/T-cell interactions play a critical role in the systemic response to infection. Distinct patterns of cytokines are produced by two different types of T-helper cells (Th). Th1 cells secrete interleukin-2 (IL-2) and interferon-gamma (IFN-gamma), whereas Th2 cells produce IL-4, IL-5, IL-6, IL-10, and IL-13. In volunteers systemic endotoxin administration initiates many features of gram-negative sepsis including cytokine release, but the patterns (i.e., Th1/Th2 patterns) have not yet been studied. In this institutional review board-approved study we investigated the effect of an intravenous bolus of endotoxin from Escherichia coli (4 ng/kg body weight) on the Th1/Th2 response in four female and four male volunteers (mean age 27.1 +/- 0.8 years). Plasma cytokine levels for IL-2, IL-4, IL-10, IL-12, and IFN-gamma and heart rate, mean arterial pressure, temperature, white blood cell, and differential blood count were determined before and hourly for 5 hours after endotoxin administration. All volunteers had tachycardia, decreased mean arterial pressure, fever, and leukocytosis. IL-10 was significantly (p < 0.05) elevated (9.4 +/- 3.9 pg/ml vs 60.9 +/- 19.3 pg/ml) 3 hours after endotoxin was administered, whereas IL-2 levels were decreased (69 +/- 26 U/ml vs 30.6 +/- 14.9 U/ml). IL-4 and IFN-gamma were not detectable in plasma. No changes were seen in the plasma levels of IL-12. Systemic responses did not correlate with changes in cytokine levels. Cytokine patterns found in this study suggest that after low-dose endotoxin administration the T-cell immune response is shifted towards the Th2 cell type response. This early shift towards a Th2 cell response may contribute to the depressed cell-mediated immune response associated with sepsis.

Adult↗