Routine preoperative "one-shot" intravenous pyelography is not indicated in all patients with penetrating abdominal trauma.

BACKGROUND: To determine which patients need a "one-shot" intravenous pyelogram (IVP) before laparotomy for penetrating abdominal trauma. STUDY DESIGN: Over a 15-month period, 240 laparotomies were performed for penetrating trauma at our urban level I trauma center. Prospectively collected data included clinical suspicion of genitourinary injury, results of preoperative IVP, intraoperative findings, and operative decisions influenced by the IVP. RESULTS: Preoperative IVP was performed in 175 patients (73%). Of these, 71 (41%) had suspicion of a renal injury based on the presence of a flank wound or gross hematuria. The IVP was believed to influence operative decisions in six patients, all in this group. Each of these six patients had either a shattered kidney or a renovascular injury and had a nephrectomy performed with the knowledge that a normal functioning kidney was present on the contralateral side. No patient without a flank wound or gross hematuria had an IVP that was judged to be helpful intraoperatively. Preoperative IVP was helpful only in patients with flank wounds or gross hematuria. Nephrectomy was performed in two additional patients who did not undergo IVP, both of whom presented in shock. CONCLUSIONS: Routine preoperative IVP is not necessary in all patients undergoing laparotomy for penetrating trauma. The number of IVPs can be safely reduced by 60% if the indications are narrowed to include only those stable patients with a flank wound or gross hematuria.

Safety of 65 degrees C intravenous fluid for the treatment of hypothermia.

BACKGROUND: To demonstrate the safety and efficacy of 65 degrees C (149 degrees F) centrally administered intravenous fluid (CIVF) compared to conventional 40 degrees C (104 degrees F) CIVF in the treatment of hypothermia. METHOD: Ten beagles (9-13 kg) were prospectively randomized to receive 65 degrees C or 40 degrees C CIVF. They were anesthetized and data were collected at baseline, during hypothermia, and after 1 and 2 hours of rewarming. The plasma free/total hemoglobin (PFHb/THb) was measured to detect hemolysis. Each subject was cooled to 30 degrees C (86 degrees F) and then received either 65 degrees C or 40 degrees C CIVF through a specialized catheter in the superior vena cava for 2 hours in addition to conventional rewarming techniques. All subjects survived 7 days, after which they were sacrificed and a complete autopsy was performed. RESULTS: The rewarming rate was 3.7 degrees C/hr in the 65 degrees C CIVF group and 1.75 degrees C/hr in the 40 degrees C CIVF group. Core temperatures were significantly different after 1 hour (33.4 degrees +/- 0.77 degrees versus 31.7 degrees +/- 0.57 degrees, P < 0.01) and 2 hours (37 degrees +/- 1.03 degrees versus 33.4 degrees +/- 0.89 degrees, P < 0.001). PFHb/THb was not different. Two intimal injuries occurred in each group but these were remote from the infusion site. Blinded examination by two pathologists could not differentiate the etiology of these injuries from mechanical trauma. CONCLUSION: CIVF at 65 degrees C is a safe and effective means of treating hypothermia.

Computed tomography screens stable patients at risk for penetrating cardiac injury.

OBJECTIVE: To determine the accuracy of CT of the chest in diagnosing the presence of cardiac injury in stable patients with penetrating chest injuries. METHODS: A retrospective chart review of a convenience sample of stable patients with penetrating thoracic wounds evaluated for hemopericardium using chest CT at an urban level I trauma center. RESULTS: 60 stable patients with penetrating wounds in proximity to the heart underwent CT. Three patients had radiographic evidence of pericardial fluid, and 1 had an equivocal study. These 4 patients underwent subxiphoid pericardial window exploration: 2 had only clear fluid present, the other 2 had hemopericardium. The latter patients had a total of 3 cardiac and 1 diaphragmatic injuries, which were repaired at subsequent sternotomy. None of the 56 patients who had negative CTs had further clinical evidence of cardiac injury. The sensitivity, specificity, and accuracy of CT in this setting for hemopericardium are 100% (95% CI 18-100%), 96.6% (95% CI 88-100%), and 96.7% (95% CI 89-100%), respectively. CONCLUSION: Chest CT may be a useful test for diagnosing the presence of hemopericardium in the setting of penetrating thoracic injury. With the caveat that the patient must be removed from a closely monitored environment, the authors the use of CT in stable patients with penetrating chest wounds whenever echocardiography is unavailable.

Limiting cardiac evaluation in patients with suspected myocardial contusion.

A great deal of time and effort is spent attempting to diagnose myocardial contusion in patients with blunt thoracic trauma. Many diagnostic protocols have been proposed in the past. However, there is no test with sufficient specificity to predict which patients will develop complications that will require therapy. Recent studies have raised the question of limiting the cardiac evaluation in certain selected patients with blunt thoracic trauma. We prospectively studied the safety of limiting the cardiac evaluation in patients who were hemodynamically stable, had no history of cardiac disease, had a normal baseline ECG, did not require surgery or neurological observation for associated injuries, and were less than 55 years of age. These patients represent the majority of patients considered at risk for myocardial contusion when mechanism is the sole criterion. These patients were simply admitted for 24 hours of continuous cardiac monitoring. No patient developed any complications of myocardial contusion requiring therapy. We conclude that it is safe to limit the cardiac evaluation in this group of patients.

Experience with three prosthetic materials in temporary abdominal wall closure.

There are circumstances that make abdominal wall closure unsafe and technically impossible after laparotomy for trauma. In these difficult cases, prosthetic materials may be necessary to temporarily close the abdominal wall. To determine the optimal prosthetic in these instances, a retrospective chart review was conducted in our urban Level I trauma center. Twenty-five patients received 31 abdominal wall prostheses over a 4-year period. There were 7, 8, and 10 patients with 7 Marlex, 9 Dexon, and 15 Goretex prostheses, respectively. Each patient had only one type of prosthesis placed. The average age was 30.7 +/- 12.0 years, injury severity score was 20.3 +/- 7.4, and abdominal trauma index was 35.9 +/- 18.0; there was no significant difference in these values between groups. Eight patients died soon after the prosthesis was placed (average, 12.9 days) secondary to ongoing shock or multiple organ failure. Three of the seven surviving Goretex patients (43%) were intentionally left with small hernias. Three of the six Dexon patients (50%) were left with hernias; one of these eviscerated on day 150 and subsequently died, and the others have disabling gigantic hernias. Three of the four Marlex patients (75%) developed fistulae as a result of erosion into the small bowel or colon. One Marlex patient suffered with a chronically draining abdominal wound for 398 days prior to definitive closure. Goretex appears to be the best prosthetic for temporary abdominal wall closure because it causes less inflammatory reaction because of its smooth surface. It is therefore easier to retrieve at the time of definitive closure and carries less risk of fistula formation than other prostheses. Our Dexon patients suffered with gigantic hernias and one died because of complications of evisceration. We have abandoned the use of Marlex in abdominal wall closure because of the high incidence of fistula formation. We advocate the use of Goretex in temporary abdominal wall closure in this challenging group of patients.

Aspiration of free blood from the peritoneal cavity does not mandate immediate laparotomy.

The objective was to establish the relationship between the aspiration of free blood (+ASP) versus diagnostic peritoneal lavage (DPL), abdominal injury severity, hemodynamic instability, and the need for immediate operative intervention. We prospectively compared the significance of +ASP to +DPL in our level I trauma center. Consecutive patients received sequential needle tap, catheter aspiration (ASP), and DPL. If gross blood was withdrawn during the tap or ASP, it was returned to the peritoneal cavity before completing the DPL. The DPL was considered positive if there were > 100,000 RBCs for blunt injuries or anterior abdominal stab wounds, or > 10,000 RBCs for other penetrating injuries. During a 12-month period, 566 patients fulfilled the study criteria; they were 50 per cent blunt and 50 per cent penetrating trauma. There were 70 patients with both +ASP/+DPL, 30 with -ASP/+DPL and 4 with +ASP but -DPL. Exploratory laparotomy was performed on these 104 patients (18.4%), 22 of which were considered nontherapeutic. The ATI was statistically higher in the +ASP patients (14.9 +/- 12.9 versus 8.5 +/- 8.2, P < 0.05) but was not clinically different. Overall injury severity and hemodynamic stability were not different in the two groups. The sensitivity of DPL at detecting intra-abdominal injury was higher than the ASP group (98% versus 72%), but the specificities were equal (98%). Because +ASP patients are not more critically injured or unstable than +DPL patients, and because DPL is more accurate in detecting the need for operative intervention, aspiration should be abandoned as part of the DPL procedure in patients with abdominal trauma.

Buckshot colic: case report and review of the literature.

Three weeks after a shotgun wound to the chest and abdomen, a patient developed acute ureteral colic caused by a migrating shotgun pellet. The pellet passed spontaneously. A search of the literature revealed 25 similar cases of this unusual complication of missile injuries to the abdomen. These cases are reviewed and analyzed. Ureteral obstruction from migrating retained missiles is an unusual complication of missile injuries to the abdomen. Cases have been described occurring after shotgun, gunshot, and shrapnel wounds. Cases involving bullets and shrapnel fragments usually have had long latent periods after the initial injury and required surgery to remove the obstructing projectile. In contrast, cases of "buckshot colic" from shotgun pellets present earlier and often resolve with spontaneous passage of the pellet. The following report illustrates how conservative management can be successful in cases of "buckshot colic."

Risks of human immunodeficiency virus infection to patients and healthcare personnel.

The risk of nosocomial human immunodeficiency virus (HIV) infection among hospitalized patients comes almost exclusively from transfusion of fresh blood products. Current estimates of the risk of HIV infection from the transfusion of blood or components vary from 1/40,000 to 1/250,000 (0.0025% to 0.0004%), with the most probable likelihood estimated to be 1/153,000 (0.0007%). The major route of transmitting such HIV infection is via blood collected during the interval between infection of the donor and development of a detectable circulating antibody level to the AIDS virus (i.e., the "window period"). The current risk to hemophiliacs receiving treated coagulation factor concentrates is negligible. The risk to healthcare personnel of acquiring HIV infection from accidental puncture wounds and from handling HIV-infected blood or body fluids is 0.42% per episode. Most reported seroconversions have resulted from penetrating injuries with sharp objects contaminated with HIV-positive blood. The degree of risk to healthcare workers will vary with the community, the patient population served, and the frequency of penetrating injuries.

Optimal prosthetic for acute replacement of the abdominal wall.

OBJECTIVE: To compare two prostheses for use in acute abdominal wall replacement in the presence and absence of peritonitis. MATERIALS AND METHODS: Forty male Sprague-Dawley rats underwent full-thickness removal of a 2 x 3 cm portion of their anterior abdominal wall. Twenty rats had intraperitoneal contamination with stool slurry. Ten rats in each group (contaminated and noncontaminated) had a 2 x 3 cm piece of Gore-Tex dual-mesh expanded polytetrafluoroethylene (PTFE) sewn full-thickness to cover the abdominal wall defect. The remaining 10 rats in each group had replacement with a 2 x 3 cm piece of Dexon polyglycolic acid mesh (PGA). The rats were then awakened and returned to their cages. Rats were humanely killed at the end of a 3-week observation period or at the time of fistula formation or evisceration. At necropsy, the density of intraabdominal adhesions was graded on a scale of 0 to 3, and the extent of reepithelialization was noted. Results were analyzed with the Student's t test or Fisher's exact method of chi2 test as indicated. RESULTS: Nineteen PTFE rats and 10 PGA rats survived the observation period, The PTFE rats had significantly fewer adhesions (0.10+/-0.30 vs. 1.27+/-1.49,p < 0.005) and significantly more reepithelialization of their wounds (78.2+/-23.4% vs. 43.6+/-50.4%,p < 0.05) than the PGA rats. Evisceration and fistula formation occurred more frequently in the PGA group. The mortality in the PTFE rats was significantly less than the PGA rats (5% vs. 50%,p < 0.001.) Notably, the contaminated PGA rats had a significantly higher mortality (90%,p < 0.001) than any of the other subgroups. CONCLUSION: PTFE is superior to PGA as a replacement prosthesis for acute abdominal wall defects. There are significantly fewer adhesions, improved epithelialization of the wound, and less morbidity and mortality when PTFE is used. This finding is especially true in the presence of intraperitoneal fecal soilage.