Alteration in Kupffer cell function after mild hemorrhagic shock.

Functional changes in Kupffer cells occur after profound hemorrhagic shock. This study was performed to demonstrate if Kupffer cell changes also occur after mild hemorrhagic shock. Sprague-Dawley rats were bled to a systolic blood pressure of 60 to 70 mmHg and resuscitated with Lactated Ringers solution (twice the shed blood volume) after 30 min. Resuscitation produced immediate recovery of blood pressure and allowed long-term recovery of the animals. Sham animals received anesthesia and monitoring only. Thirty minutes after resuscitation, Kupffer cells were isolated by centrifugal elutriation and cultured for 48 h. In Kupffer cells isolated from shocked animals, phorbol ester-stimulated superoxide production increased 7-fold and lipopolysaccharide- (LPS) stimulated prostaglandin E2 (PGE2) production increased 4-fold. Tumor necrosis factor-alpha (TNFalpha) production, on the other hand, was decreased by 50%. A non-significant trend toward increased phagocytosis was also observed, whereas LPS-stimulated nitric oxide production was unchanged. In conclusion, mild hemorrhagic shock produced increases in superoxide and PGE2 production, and decreases in TNFalpha production by Kupffer cells, changes that may be appropriate to defend against the infectious challenges that often follows trauma and hemorrhage.

Diagnosis and management of blunt small bowel injury: a survey of the membership of the American Association for the Surgery of Trauma.

BACKGROUND: Blunt small bowel injury (SBI) may be difficult to diagnose accurately. Diagnostic delays are associated with increased morbidity and mortality. METHODS: A cross-sectional survey of members of the American Association for the Surgery of Trauma was conducted. A Likert-type multiple-choice scale was used to evaluate use and usefulness of diagnostic and laboratory tests. Data were analyzed by using univariate and multivariate techniques. RESULTS: A total of 461 of the 702 members (68%) surveyed responded, of which 133 members (29%) were excluded because they did not currently manage adult SBI. Of the remaining 328 respondents, 244 members (74%) reported prior experience as the most important influence on their current practice of diagnosing blunt SBI. None of the standard laboratory tests were reported as useful. Seventy-seven percent of respondents use computed tomographic (CT) scan most or all of the time for diagnosis (p < 0.05 compared with other modalities). Most respondents estimated their annual incidence of SBI at 5% with a >15% frequency of delay in diagnosis. Forty-four percent of the respondents estimated the mortality associated with a delay in diagnosis at < or =5%. Respondents varied significantly in their management of the patient with an unreliable abdominal exam and a CT scan finding of isolated free fluid. In patients with head injuries, 28% observe, 12% repeat the CT scan, 42% perform diagnostic peritoneal lavage, and 16% operate. For intoxicated patients, 51% observe, 11% repeat the CT scan, 26% perform diagnostic peritoneal lavage, and 10% operate. A more aggressive approach with diagnostic and operative intervention was significantly (p < 0.05) advocated by respondents practicing without residents, more than 15 years out from residency, or by those with a perception of higher morbidity and mortality from delays in diagnosis. CONCLUSION: There is significant variation in the diagnostic approach to the patient with suspected SBI. The perceived mortality of delayed diagnosis is much less than reported. Those surgeons with more experience or perception of greater morbidity and mortality from a delayed diagnosis are more aggressive. Further investigation into the diagnosis and treatment of this injury is needed.

Bovine hemoglobin-based oxygen carrier (HBOC-201) for resuscitation of uncontrolled, exsanguinating liver injury in swine. Carolina Resuscitation Research Group.

In the setting of rapidly exsanguinating hemorrhage, resuscitation with intravenous (i.v.) crystalloid solution may not sustain survival before availability of allogenic blood transfusion and surgery. This study tested the hypothesis that bovine hemoglobin-based oxygen carrier, HBOC-201, would improve resuscitation and extend early survival from exsanguinating hemorrhage. This study simulated the prehospital scenario of rapidly exsanguinating hemorrhage with prolonged prehospital time and lack of blood availability. Severe hemorrhagic shock was induced in swine by using multiple liver lacerations. At 9 min after the onset of bleeding, swine were randomized to receive approximately 10 mL/kg/min of i.v. lactated Ringer's solution (n = 10) or HBOC-201 (n = 7) to achieve a mean aortic pressure (MAP) of 60 mmHg. Thereafter, infusion rate was adjusted to maintain MAP at 60 mmHg for up to 2 h. All animals were initially successfully resuscitated. The results showed 2-h survival was 1 of 10 with lactated Ringer's and 7 of 7 with HBOC-201 (P = 0.0004). Nine lactated Ringer's swine had cardiovascular collapse at 36 +/- 10 min. Lactate at 30 min was 18 +/- 3 mmol/L with lactated Ringer's and 12 +/- 2 mmol/L with HBOC-201 (P < 0.05). Hematocrit was <1% in 9 of 10 lactated Ringer's and 6 of 7 HBOC-201 animals. These data indicate that HBOC-201 improved early survival and stabilized hemodynamic and metabolic parameters vs. lactated Ringer's in this swine model of liver injury with uncontrolled, lethal hemorrhage that simulates the prehospital care environment where allogenic blood is unavailable.

Prospective randomized trial of early initiation and hospital discharge on a liquid diet following elective intestinal surgery.

Length of hospital stay after elective intestinal surgery may be related to patient tolerance of a diet. We hypothesized that early initiation and discharge home on a clear liquid diet would decrease the length of hospital stay without increasing morbidity. The aim of this study was to determine if early initiation and discharge on a clear liquid diet decreases the length of hospital stay and is safe. Forty-four patients were randomly assigned to either a standard diet or a clear liquid diet. A standard diet (n = 17) was begun after the passage of flatus or stool, and consisted of clear liquids to a volume of approximately 750 ml, then three solid meals, and discharge thereafter. Patients randomized to a clear liquid diet (n = 27) received 30 ml/hr of clear liquids on postoperative day 2, unlimited clear liquids on postoperative day 3, and were dismissed on a clear liquid diet on postoperative day 4. All patients were followed by a daily telephone call and clinic visit. The primary outcome variable was length of hospital stay. The incidence of postoperative intestinal-related sequelae, complications, and readmission rates did not differ between groups. Postdischarge intestinal symptoms were common in both groups but tended to resolve faster in the patients on a standard diet. The length of hospital stay was decreased in the patients on a clear liquid diet compared to those on a standard diet (6.1 +/- 1.1 days vs. 4.4 +/- 0.2 days; P = 0.09), but total hospital costs did not differ. Early initiation and hospital discharge on a clear liquid diet after elective intestinal surgery decreases the length of hospital stay and is safe.

The effector component of the cytotoxic T-lymphocyte response has a biphasic pattern after burn injury.

INTRODUCTION: Burn injury delays allograft rejection and impairs the host defense against infection. These functions are mediated via the cytotoxic T-lymphocyte (CTL) response. The CTL response is divided into antigen recognition/processing and effector phases. Presensitization allows selective analysis of changes, induced by burn injury, in the effector limb of the CTL response in relation to time and burn size. METHODS: Anesthetized CBA mice were primed with either a flank allograft from C57BL/6 (B6) mice or an autograft (negative control). Five weeks after grafting, animals were anesthetized and received either a 0, 20, or 40% burn. Spleens were harvested 3, 7, 10, and 14 days after burn injury (n = 96), cocultured with B6 stimulator splenocytes, and assessed for CTL response to radiolabeled allogeneic targets in a 51Cr release assay. In experiment 2, spleens were harvested from unburned and 40% burned animals on Postburn Days 3 and 14. After triple staining, cells were analyzed by flow cytometry for CD4, CD8, and CD25 antigens. In experiment 3, splenocytes from 0 and 40% burned animals on Postburn Days 3 and 14, were cocultured with B6 stimulators for 5 days. Supernatants were evaluated for interleukin (IL)-2, IL-5, and interferon-gamma (IFN-gamma) using ELISA: RESULTS: The CTL response for 20 and 40% burned animals decreased 3 days postburn (-11.9 and -30.1%, P < 0.05), returned to baseline in 7-10 days, and was increased by 14 days postburn (15.8 and 22.6%, P < 0.05). The T-helper lymphocyte population (CD4) from 40% burn animals was significantly decreased on Postburn Days 3 and 14 (10.12 +/- 0.45% vs 11.78 +/- 0.29% and 10.19 +/- 0.24% vs 14.21 +/- 0.97%, respectively, P < 0.05). The CTL effector (CD8) splenocyte population was significantly higher in the burned animals on Postburn Day 14 (4.55% vs 3.71%, P < 0.05). On Postburn Day 3, average IL-5 production was higher in the burned animals (1.80 pg/ml vs 0.59 pg/ml, respectively, P < 0.05). The burn group, on Postburn Days 3 and 14, showed a decrease in mean IL-2 production (212.81 pg/ml vs 263.6 pg/ml and 342.7 pg/ml vs 421.4 pg/ml, respectively, P < 0.05). Mean IFN-gamma production on Postburn Days 3 and 14 was decreased in burned mice (263.75 pg/ml vs 285.57 pg/ml and 218.16 pg/ml vs 263.42 pg/ml, P < 0.05). CONCLUSIONS: Burn injury impairs the effector limb of the CTL response as a function of burn size in the immediate postburn period. CTL activity returns to baseline within 7-10 days postburn and has a rebound increase by Day 14. Early CTL suppression, after burn injury, may be due to a decrease in the T-helper subpopulation. The late increase in cytotoxicity may be secondary to an increase in the effector CTL population in the late postburn period. Burn injury causes a T-helper-2 phenotype as demonstrated by depressed IL-2 and IFN-gamma production and increased IL-5 production.