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Dive into the research topics where R. M. Stewart is active.

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Featured researches published by R. M. Stewart.


Annals of Surgery | 1993

A prospective analysis of diagnostic laparoscopy in trauma.

Timothy C. Fabian; Martin A. Croce; R. M. Stewart; F. Elizabeth Pritchard; Gayle Minard; Kenneth A. Kudsk

OBJECTIVE This study was performed to assess current and potential future application for laparoscopy (DL) in the diagnosis of penetrating and blunt injuries. Efficacy, safety, and cost analyses were performed. SUMMARY BACKGROUND DATA Diagnostic peritoneal lavage (DPL) and computed tomography (CT) have been the mainstays in recent years for diagnosis of equivocal nontherapeutic laparotomy, whereas CT is not helpful for the vast majority of penetrating wounds. DL may be a useful adjunct to fill in these gaps. METHODS Hemodynamically stable patients with equivocal evidence of intraabdominal injury were prospectively entered into the protocol. DL was performed under general anesthesia; patients with wounds penetrating the peritoneum or blunt injury with significant organ injury underwent laparotomy. RESULTS Over 19 months, 182 patients (55% stab, 36% GSW, 9% blunt) were studied. No peritoneal penetration was found at DL in 55% of penetrating wounds with 66% of the remainder having therapeutic laparotomy, 17% nontherapeutic laparotomy, and 17% negative laparotomy. Therapeutic laparotomy was performed in 53% of blunt injuries after DL. Tension pneumothorax occurred in one patient and one had an iatrogenic small bowel injury. Charges for DL were


American Journal of Surgery | 1994

Is resection with primary anastomosis following destructive colon wounds always safe

R. M. Stewart; Timothy C. Fabian; Martin A. Croce; F. Elizabeth Pritchard; Gayle Minard; Kenneth A. Kudsk

3,325 per patient compared with


Journal of Trauma-injury Infection and Critical Care | 1992

Correlation of Abdominal Trauma Index and Injury Severity Score with abdominal septic complications in penetrating and blunt trauma

Martin A. Croce; Timothy C. Fabian; R. M. Stewart; F. E. Pritchard; Gayle Minard; Kenneth A. Kudsk

3,320 for a similar group undergoing negative laparotomy before this protocol. CONCLUSIONS DL is a safe modality for trauma. With current technology, DL is most efficacious for evaluation of equivocal penetrating wounds. Significant cost savings would be gained by performance under local anesthesia. Development of miniaturized optics, bowel clamps, retractors, and stapling devices will reduce overall costs and permit some therapeutic applications for laparoscopy in trauma management.


Surgery | 1995

Gastric and extragastric actions of the histamine antagonist ranitidine during posttraumatic sepsis

R. M. Stewart; Timothy C. Fabian; Matthew J. Fabian; Lisa L. Trenthem; F. Elizabeth Pritchard; Martin A. Croce; Kenneth G. Proctor

Resection with primary anastomosis was associated with a 14% anastomotic leak rate in this review of 60 patients with destructive colon wounds. The presence of an underlying medical illness or massive blood transfusion was associated with anastomotic complications. In the high-risk subset of patients who had one or both of these risk factors, the anastomotic leak rate was 42%. The incidence of anastomotic leak in previously healthy patients without massive transfusion was 3%. Ileocolostomies were no safer than colocolostomies. We conclude that resection with anastomosis should not be performed on all patients with destructive colon injuries, as the risk of anastomotic leak is prohibitive in those with either massive blood loss or underlying medical illness. We continue to perform primary anastomosis in healthy patients without excessive blood loss.


Shock | 1994

Plasma tumor necrosis factor and post-traumatic hyperdynamic sepsis evoked by endotoxin.

John D. Wilson; R. M. Stewart; Timothy C. Fabian; Joseph A. Weinberg; Lisa L. Trenthem; Kenneth G. Proctor

The Abdominal Trauma Index (ATI) was designed to stratify patients with penetrating injuries, and has been used to classify patients with blunt trauma. The Injury Severity Score (ISS) was originally designed to stratify victims of blunt trauma, and it has also been used for victims of penetrating trauma. We attempted to validate the use of ISS and ATI for both penetrating and blunt trauma. A total of 592 penetrating and 334 blunt trauma patients who underwent laparotomy over a 5-year period were evaluated. The overall rate of abdominal sepsis was 7.5% for blunt trauma and 7.6% for penetrating trauma. Mortality (excluding deaths within 48 hours) was 7% for blunt trauma and 1% for penetrating trauma. In the penetrating injury population, an ATI value greater than 15 and an ATI value greater than 25 were significantly associated with abdominal septic complications (ASCs) (p less than 0.001, both comparisons). An ISS greater than or equal to 16 was also associated with ASCs (p less than 0.001). The ASC rate for gunshots was higher than that for stab wounds (11% vs. 2%; p less than 0.001). In the blunt group, an ATI value greater than 15 and an ATI value greater than 25 were associated with ASCs (p less than 0.01 and p less than 0.001, respectively). The association of ASCs and ISS was linear with increasing ISS in patients with blunt abdominal trauma.(ABSTRACT TRUNCATED AT 250 WORDS)


Journal of Trauma-injury Infection and Critical Care | 1993

Analysis of charges associated with diagnosis of nosocomial pneumonia: Can routine bronchoscopy be justified?

Martin A. Croce; Timothy C. Fabian; B. Shaw; R. M. Stewart; F. E. Pritchard; Gayle Minard; Kenneth A. Kudsk; Vickie S. Baselski

BACKGROUND Histamine H2 antagonists (e.g., ranitidine) are generally thought to specifically reduce gastric acid secretion and are commonly used for stress ulcer prophylaxis in critically ill patients because of their efficacy and safety profile. A few reports suggest that ranitidine might also bind to extragastric sites and/or act as an immunomodulator. The potential effects on posttraumatic sepsis are unknown. METHODS Mongrel pigs (n = 24) were anesthetized with fentanyl, injured by a 10 kg steel bar dropped from a height of 1 m onto the fleshy portion of the posterior thigh, and then 35% of their blood volume was drained through the arterial catheter. All the shed blood plus two times the hemorrhage volume as lactated Ringers solution was infused after a 1-hour shock period. Either vehicle or ranitidine (1.5 mg/kg) was intravenously administered at the time of resuscitation and every 12 hours thereafter in a blinded fashion. After 72 hours a septic challenge was administered (15 micrograms/kg Escherichia coli lipopolysaccharide [LPS] x 30 min). Serial gastroscopy, gastric pH, hemodynamics, leukocyte counts, cortisol, and tumor necrosis factor were recorded for 180 minutes after LPS. RESULTS Immediately before LPS all hemodynamic variables were identical between treatments, but gastric pH was slightly higher and stress gastritis was marginally lower with ranitidine. LPS caused profound leukopenia and a hyperdynamic circulatory response (i.e., tachycardia, increased cardiac output, and decreased peripheral vascular resistance at relatively constant blood pressure); these changes were not altered by ranitidine. Gastric pH remained elevated after LPS with ranitidine, but LPS-induced gastritis was not modified. Ranitidine delayed the LPS-induced ventilation-perfusion imbalance and attenuated the peak increase in the proinflammatory cytokine, tumor necrosis factor, without altering its antiinflammatory opponent, cortisol. Similar changes were observed in four additional animals treated with cimetidine. The proportion of circulating neutrophils and lymphocytes was slightly altered 180 minutes after LPS, but there was no obvious effect on T lymphocytes in vivo, and no effect on the LPS-induced increase in neutrophil CD18 expression in vitro was seen. CONCLUSIONS (1) Ranitidine increased gastric pH, which blunted the stress gastritis caused by trauma but not that caused by LPS; (2) ranitidine delayed the early LPS-evoked pulmonary changes and reduced the tumor necrosis factor spike, which is consistent with a favorable immunomodulatory action that has been reported in patients who are critically ill or are undergoing an elective abdominal surgical procedure; (3) the mechanism is probably related to H2 receptor antagonism rather than to a nonspecific side effect of ranitidine, which suggests that histamine may have a previously unrecognized role in posttraumatic septic responses; and (4) the site of action is probably not in the heart or peripheral resistance vessels, but salutary effects on circulating lymphocytes or neutrophils cannot be excluded.


Current Problems in Surgery | 2002

Current issues in trauma.

Timothy C. Fabian; Tiffany K. Bee; Catherine Cagianos; Preston R. Miller; Martin A. Croce; R. M. Stewart; Gayle Minard; Louis J. Magnotti; Joe H. Patton

To examine the role of systemic plasma tumor necrosis factor (TNF) in the septic response following trauma, an endotoxin (lipopolysaccharide (LPS)) challenge was administered to anesthetized mongrel pigs 72 h following either hemorrhagic shock/resuscitation or sham shock. For TNF to be considered a mediator, at least two conditions should be satisfied: a TNF increase should precede other manifestations of the septic response and the magnitude of that increase should correlate with the symptoms. Immediately following resuscitation from shock, hemodynamics were stable, but heart rate, cardiac index (Cl), and systemic oxygen delivery (DO2) were elevated 20–60%, and systemic vascular resistance (SVR) was decreased 40%, relative to the preshock baseline. After 72 h, the animals were reanesthetized, reinstrumented, and all hemodynamic values were near normal in both groups. At this point, either 1.5 (shock, n = 2; sham, n = 2), 15 (shock, n = 7; sham, n = 6) or 150 (shock, n = 11; sham, n = 4) μg/kg of Escherichia coli LPS was administered intravenously over 30 min. Serial hemodynamic data, complete blood counts, and TNF were recorded for 3 h post-LPS. LPS evoked profound leukopenia and pulmonary hypertension within 15 min that was followed by a hyperdynamic septic response (i.e., progressive arterial desaturation, tachypnea, tachycardia, increased Cl, and decreased SVR) and rise in plasma TNF at 60–90 min. In the shock group, LPS-evoked TNF changes were less than or equal to those in the sham group, even though mortality was higher after shock. By 60 min after 15 μg/kg LPS, plasma TNF was 10 ± 2 vs. 21 ± 4 units/ml in shock vs. sham (p < .05). The corresponding mortality after 3 h was 2/7 in shock and 0/6 in sham. After 150 μg/kg LPS, plasma TNF increased to 16–18 units/ml in both groups, but the 3 h mortality was 8/11 in shock and 1/4 in sham. Since plasma TNF did not rise until after other symptoms of an LPS-evoked inflammatory response were already apparent and since the increment in plasma TNF was not potentiated by a prior bout of resuscitated shock, it is unlikely that the response evoked by a septic challenge following traumatic shock can be directly attributed to excessive levels of systemic TNF.


Surgery | 1994

Gamma-scintigraphy and early hepatocellular dysfunction during posttraumatic sepsis

M. P. McGinty; R. M. Stewart; Matthew J. Fabian; Timothy C. Fabian; Kenneth G. Proctor


Surgery | 1994

Splanchnic and systemic hemodynamic responses to portal vein endotoxin after resuscitation from hemorrhagic shock

T. J. Gavin; Timothy C. Fabian; J. D. Wilson; Lisa L. Trenthem; F. E. Pritchard; Martin A. Croce; R. M. Stewart; Kenneth G. Proctor


Critical Care Medicine | 1993

HEMORRHAGIC SHOCK DECREASES THE CYTOKINE RESPONSE TO ENDOTOXEMIA

John D. Wilson; R. M. Stewart; Timothy C. Fabian; Lisa L. Trenthem; Kenneth G. Proctor

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Timothy C. Fabian

University of Tennessee Health Science Center

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Martin A. Croce

University of Tennessee Health Science Center

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Gayle Minard

University of Tennessee Health Science Center

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Kenneth A. Kudsk

University of Wisconsin-Madison

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Lisa L. Trenthem

University of Tennessee Health Science Center

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F. E. Pritchard

University of Tennessee Health Science Center

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F. Elizabeth Pritchard

University of Tennessee Health Science Center

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Matthew J. Fabian

University of Tennessee Health Science Center

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B. Shaw

University of Tennessee Health Science Center

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