Peter P. Lopez

Massive transfusion in trauma patients: tissue hemoglobin oxygen saturation predicts poor outcome.

BACKGROUND Severely bleeding trauma patients requiring massive transfusion (MT) often experience poor outcomes. Our purpose was to determine the potential role of near infrared spectrometry derived tissue hemoglobin oxygen saturation (StO2) monitoring in early prediction of MT, and in the identification of those MT patients who will have poor outcomes. METHODS Data from a prospective multi-institution StO2 monitoring study were analyzed to determine the current epidemiology of MT (defined as transfusion volume >/=10 units packed red blood cells in 24 hours of hospitalization). Multivariate logistic regression was used to develop prediction models. RESULTS Seven US level I trauma centers (TC) enrolled 383 patients. 114 (30%) required MT. MT progressed rapidly (40% exceeded MT threshold 2 hours after TC arrival, 80% after 6 hours). One third of MT patients died. Two thirds of deaths were due to early exsanguination and two thirds of early exsanguination patients died within 6 hours. One third of the early MT survivors developed multiple organ dysfunction syndrome. MT could be predicted with standard, readily available clinical data within 30 minutes and 60 minutes of TC arrival (area under the receiver operating characteristic curve = 0.78 and 0.80). In patients who required MT, StO2 was the only consistent predictor of poor outcome (multiple organ dysfunction syndrome or death). CONCLUSION MT progresses rapidly to significant morbidity and mortality despite level I TC care. Patients who require MT can be predicted early, and persistent low StO2 identifies those MT patients destined to have poor outcome. The ultimate goal is to identify these high risk patients as early as possible to test new strategies to improve outcome. Further validation studies are needed to analyze appropriate allocation and study appropriate use of damage control interventions.

Secondary ultrasound examination increases the sensitivity of the FAST exam in blunt trauma.

INTRODUCTION Approximately one third of stable patients with significant intra-abdominal injury do not have significant intraperitoneal blood evident on admission. We hypothesized that a delayed, repeat ultrasound study (Secondary Ultrasound--SUS) will reveal additional intra-abdominal injuries and hemoperitoneum. METHODS We performed a prospective observational study of trauma patients at our Level I trauma center from April 2003 to December 2003. Patients underwent an initial ultrasound (US), followed by a SUS examination within 24 hours of admission. Patients not eligible for a SUS because of early discharge, operative intervention or death were excluded. All US and SUS exams were performed and evaluated by surgical/emergency medicine house staff or surgical attendings. RESULTS Five hundred forty-seven patients had both an initial US and a SUS examination. The sensitivity of the initial US in this patient population was 31.1% and increased to 72.1% on SUS (p < 0.001) for intra-abdominal injury or intra-abdominal fluid. The specificity for the initial US was 99.8% and 99.8% for SUS. The negative predictive value was 92.0% for the initial US and increased to 96.6% for SUS (p = 0.002). The accuracy of the initial ultrasound was 92.1% and increased to 96.7% on the SUS (p < 0.002). No patient with a negative SUS after 4 hours developed clinically significant hemoperitoneum. CONCLUSION A secondary ultrasound of the abdomen significantly increases the sensitivity of ultrasound to detect intra-abdominal injury.

Development of a sleeve gastrectomy weight loss model in obese Zucker rats.

BACKGROUND Obesity promotes the development of diabetes and cardiovascular disease. The most effective weight loss treatment is bariatric surgery, but results greatly vary depending on the procedure. Sleeve gastrectomy (SG) has recently emerged as a reduced risk weight loss procedure for super obese patients. However, the mechanism of weight loss from SG and its effects on obesity-induced complications are yet to be determined. Our goal was to develop an experimental model of SG in genetically obese rats. MATERIALS AND METHODS Male obese Zucker rats (400-500 g, leptin-insensitive) were anesthetized with isoflurane. After a midline laparotomy, the stomach was clamped, the greater curvature was excised, and a triple suture line was used to close the gastric remnant. Sham rats underwent laparotomy only. Metabolic parameters were followed for 14 d after surgery. RESULTS Caloric intake and body weight decreased in SG rats over 14 d by 98 +/- 10 kcal/d and 74 +/- 14 g, respectively. Blood total cholesterol levels were lower in rats that lost weight. Furthermore, blood glucose levels were lower in rats that lost weight. Active ghrelin levels were unchanged in SG rats 14 d after surgery. CONCLUSIONS These results show that SG promotes weight loss in obese Zucker rats. Furthermore, SG-induced weight loss is accompanied by improved plasma cholesterol and glucose profile. However, SG does not promote a prolonged decrease in ghrelin levels. These results suggest that SG is an effective weight loss procedure in leptin insensitivity to improve the lipid profile and decrease insulin resistance and these effects might be independent of changes in ghrelin levels.

Is there an optimal time for laparoscopic cholecystectomy in acute cholecystitis

BackgroundLaparoscopic cholecystectomy (LC) is safe in acute cholecystitis, but the exact timing remains ill-defined. This study evaluated the effect of timing of LC in patients with acute cholecystitis.MethodsProspective data from the hospital registry were reviewed. All patients admitted with acute cholecystitis from June 1994 to January 2004 were included in the cohort.ResultsLaparoscopic cholecystectomy was attempted in 1,967 patients during the study period; 80% were women, mean patient age was 44 years (range, 20–73 years). Of the 1,967 LC procedures, 1,675 were successful, and 292 were converted to an open procedure (14%). Mean operating time for LC was 1 h 44 min (SD ± 50 min), versus 3 h 5 min (SD ± 79 min) when converted to an open procedure. Average postoperative length of stay was 1.89 days (± 2.47 days) for the laparoscopic group and 4.3 days (± 2.2 days) for the conversion group. No clinically relevant differences regarding conversion rates, operative times, or postoperative length of stay were found between patients who were operated on within 48 h compared to those patients who were operated on post-admission days 3–7.ConclusionsThe timing of laparoscopic cholecystectomy in patients with acute cholecystitis has no clinically relevant effect on conversion rates, operative times, or length of stay.

Screening cervical spine MRI after normal cervical spine CT scans in patients in whom cervical spine injury cannot be excluded by physical examination

BACKGROUND Cervical spine injuries can occur in as many as 10% of patients with blunt trauma with mental status changes from closed head injuries. Despite normal results on cervical spine computed tomography (CT), magnetic resonance imaging (MRI) is often recommended to exclude ligamentous or soft tissue injury. METHODS A retrospective review was conducted of trauma patients admitted to a level I trauma center from 2002 to 2006, in whom cervical spine injuries could not be excluded by physical examination. All patients with normal results on cervical spine CT followed by cervical spine MRI were included in the analysis. RESULTS One hundred twenty patients underwent MRI to examine their cervical spines. Seven patients had abnormal MRI findings suggestive of acute traumatic injury. No MRI studies led to operative intervention. Screening MRI increased from 1% of comatose patients in 2002 to 18% in 2006. CONCLUSIONS The use of MRI in patients with normal results on cervical spine CT does not appear to alter treatment.

Complications of percutaneous endoscopic and fluoroscopic gastrostomy tube insertion procedures in 378 patients.

Gastrostomy tubes are used for primary and supplemental feeding and gastric decompression. The purpose of the study was to compare the complication rate of gastrostomy tube placement by either endoscopic or fluoroscopic technique. Between 1996 and 2004, the surgical and radiological services at a Level I trauma hospital placed gastrostomy tubes in 378 patients (endoscopy = 268, fluoroscopy = 110). The percutaneous gastrostomy group comprised 71% of the cohort with a mean age of 51 ± 21 (range: 1–93 years of age), and the percutaneous radiographic gastrostomy group comprised the remaining cohort (29%) with a mean age of 57 ± 19 (range: 17–95 years of age). Fifty-eight percent of the percutaneous gastrostomy group were female (n = 155) and 42% were male (n = 113), whereas the gender distribution for the percutaneous radiographic gastrostomy group was 33% female (n = 36) and 67% male (n = 74). There was an overall complication rate of 36% (22% and 70% for the endoscopic and fluoroscopic methods, respectively). The most frequent complication in both types of techniques was tube dislodgement (endoscopic = 32% [19/268]; fluoroscopic = 27% [21/110]). There were very few serious complications. Women had a higher rate of postprocedure complications than did men, at 35% versus 27%. We conclude that gastrostomy tube placement by either endoscopic or fluoroscopic methods results in a number of complications, though most of them are minor. Patients must therefore be informed that this is not a complication-free procedure.

The incision of choice for pregnant women with appendicitis is through McBurney’s point

BACKGROUND There is uncertainty over the optimal incision for gravid patients with appendicitis. METHODS Data were collected retrospectively from January 1, 1995, through December 31, 2000, on 374 women of childbearing age who underwent appendectomies. Of these, 23 gravid patients were evaluated. RESULTS Eighteen incisions were made over McBurneys point and five were created superior to McBurneys point. Patients in the third trimester of pregnancy all received incisions over McBurneys point. The appendix was located without difficulty in all 4 of the third trimester patients. The appendix was easily located in 94% of the incisions made through McBurneys point and 80% of the incisions made above McBurneys point. CONCLUSIONS Our clinical experience indicates that the incision for the removal of the appendix in pregnant patients in all trimesters can be successfully made over McBurneys point.

How can trauma surgeons maintain their operative skills

BACKGROUND The operative experience of the dedicated trauma surgeon is declining. Much attention has focused on the operative workload of trauma surgeons as it is critical in both maintaining operative skills and promoting the interest of surgical residents in trauma careers. We examined the operative experience of our surgical service which includes trauma, emergency general surgery, and elective general surgery to analyze changes occurring over the past decade. METHODS A retrospective study was performed by extracting data from the operative database at our Level I trauma center from January 1995 to December 2005. The cases were classified as trauma, emergency general surgery, or elective general surgery. Data were analyzed using weighted linear regression to analyze statistical significance. RESULTS Although the total number of cases performed by the trauma service remained constant, the proportion of initial operative trauma cases (<24 hours from arrival to operation) decreased from 14% to 8% (r2 = 0.91, p < 0.001) over the study period. In contrast, emergency general surgery cases increased over this time period (r2 = 0.57, p < 0.01). Elective case volume was unchanged. The majority of the waning of trauma cases was due to decreased surgery on the liver and spleen and fewer neck explorations. CONCLUSIONS Trauma operative experience decreased but emergency general surgery increased over a decade at our trauma center. It appears possible to maintain a busy operative trauma service by the inclusion of emergency general surgery consultations.

Complications of acute fatty liver of pregnancy treated with activated protein C.

IntroductionAcute fatty liver (AFL) of pregnancy is a difficult and challenging diagnosis. The treatment plan is usually supportive.Case report We present a case of a patient with AFL of pregnancy and Gram-negative endomyometritis and sepsis. Our treatment plan included the use of activated protein C (APC).Conclusion This is the first case report of the use of APC in a post-partum patient with AFL and sepsis.

CT scanning in the management of acute appendicitis.

e read with interest the article by Pritchett and coleagues concerning the use of CT scanning in the mangement of acute appendicitis as a model for assessing he financial performance of a surgical unit. They conluded that CT scan is commonly used to diagnose ppendicitis, but its use delayed time to operative ntervention. We previously reported 2 prospective randomized trils in adults with equivocal right lower quadrant pain. he first compared delineation of appendicitis by clinial examination alone, with clinical examination augented with abdominal CT scans, and found no differnces in diagnostic accuracy (90% clinical versus 92% T). Our second trial focused on women of childearing age and again identified no differences (diagnosic accuracy was 93% in both groups). We performed hese studies to prove that clinical examination by a ompetent surgeon makes CT unnecessary, but the reults have instead been interpreted as “a CT is as good s a surgeon” when making the diagnosis of acute ppendicitis. One unexpected result of widespread CT scanning in atients with right lower quadrant pain has been the apid rise in the number of appendectomies for “early ppendicitis.” The increase in nonperforated appendiitis occurred after 1995 in all age groups older than 5 ears, and paralleled increasing rates of CT imaging and aparoscopic surgery on the appendix but did not result n the expected reduction in the rate of perforation. This ork suggests that many patients who previously would ave been observed are now being subjected to unnecssary surgery.