Ronald M. Stewart

Seven hundred fifty-three consecutive deaths in a level I trauma center: the argument for injury prevention

BACKGROUND The past century has seen improvement in trauma care, with a resulting decrease in therapeutically preventable deaths. We hypothesize that further major reduction in injury mortality will be obtained through injury prevention, rather than improvements in therapy. METHODS Seven hundred fifty-three deaths in an American College of Surgeons-verified, Level I trauma center were reviewed as they occurred. Deaths were classified as therapeutically not preventable, possibly preventable, or preventable. These charts were also reviewed for factors that might have prevented or lessened the severity of the injury. RESULTS Mean age was 43, mean Glasgow Coma Scale score was 5, mean Revised Trauma Score was 4, mean Injury Severity Score was 41, and mean probability of survival was 0.25 (according to TRISS). Forty-six percent underwent cardiopulmonary resuscitation in the field, 52% died within 12 hours, 74% died within 48 hours, and 86% died within 7 days. Primary causes of death included central nervous system injury in 51%, irreversible shock in 21%, multiple injuries (shock plus central nervous system injury) in 9%, multiple organ failure/sepsis and other causes in 3%, and pulmonary embolus in 0.1%. Seven hundred one (93%) were classified as not preventable with a change in therapy, 32 (4.2%) were classified as potentially preventable with a change in therapy, and 20 were classified as preventable with a change in therapy (2.6%). Forty-six percent had cardiopulmonary resuscitation performed before or immediately on arrival to the hospital. Another 23% had vital signs present on arrival, but had a Glasgow Coma Scale score of <or= 4. Of the 546 unintentionally injured patients, 58% had an identifiable factor that contributed to the presence and/or severity of the injury (intoxication, restraint and helmet use), with 28% of patients having a positive blood alcohol level. Of the 206 patients with intentional injuries, 44% were intoxicated at the time of their death. Commensurate with driving-while-intoxicated prevention program(s), the percentage of intoxicated patients significantly ( p= 0.03) decreased from 45% to 34% over the same 7-year period. CONCLUSION Dramatically improving therapy (no errors, cure for multiple organ failure, sepsis, and pulmonary embolus) in a modern trauma system would decrease trauma mortality by 13%. In contrast, more than half of all deaths are potentially preventable with preinjury behavioral changes. Injury prevention is critical to reducing deaths in the modern trauma system.

Blunt splenic injuries: Dedicated trauma surgeons can achieve a high rate of nonoperative success in patients of all ages

BACKGROUND Selective nonoperative management (NOM) of blunt splenic injuries is becoming a more prevalent practice. Inclusion criteria for NOM, which have been a source of controversy, continue to evolve. Age > or = 55 years has been proposed as a predictor for failure of and even a contraindication to NOM of blunt splenic trauma. Additionally, the high rate of NOM in children (up to 79%) has been attributed to their management by pediatric surgeons. We evaluated our experience with NOM of blunt splenic injury with special attention to these age groups. METHODS By using our trauma registry, all patients with blunt splenic injuries (documented by computed tomography, operative findings, or both) cared for over a 36-month period, at a single American College of Surgeons verified Level I trauma center were reviewed. Detailed chart reviews were performed to examine admission demographics, laboratory data, radiologic findings, outcome measures, and patient management strategy. All patients were managed by nonpediatric trauma surgeons. We then compared our adult data with that in the recent literature and our pediatric data with that of the National Pediatric Trauma Registry over the same time period. RESULTS We identified 251 consecutive patients with blunt splenic injuries. Eighteen patients who expired in the immediate postinjury period were excluded from statistical evaluation. No deaths occurred as a result of splenic injury. Of the remaining 233 patients, 73 patients (31%) required early celiotomy, 160 patients (69%) were selected for NOM, with 151 patients (94%) being successfully managed without operation. Blunt splenic injury occurred in 23 patients age 55 years or older. Eighteen patients (78%) were selected for NOM and 17 patients (94%) were successfully treated without operation. Blunt splenic injury occurred in 35 patients less than 16 years of age. Thirty-two patients (91%) were selected for NOM. Thirty-one patients (89% of all pediatric patients) were successfully treated without operation. CONCLUSION Age > or = 55 years is not a contraindication to nonoperative management of blunt splenic injuries. Children with blunt splenic injuries can be successfully managed nonoperatively by nonpediatric trauma surgeons.

The incidence and risk of early postoperative small bowel obstruction: A cohort study☆

Early postoperative small bowel obstruction is a rare (0.69 percent incidence) but serious postoperative complication with a relatively high mortality rate (17.8 percent). Operations performed below the transverse mesocolon impose an increased risk, whereas those limited to the upper abdomen are virtually free of risk. The clinical picture of a patient who initially manifests a return of gut function and advances to a diet, but then has loss of bowel function with distention and pain is most characteristic of early postoperative small bowel obstruction. Any patient in the high-risk group demonstrating this clinical picture should be presumed to have a mechanical small bowel obstruction, and early operation should be considered.

Less Is More: Improved Outcomes in Surgical Patients with Conservative Fluid Administration and Central Venous Catheter Monitoring

BACKGROUND The ARDS Clinical Trials Network Fluid and Catheter Treatment Trial (FACTT) addressed fluid management and central monitoring of patients with acute respiratory distress syndrome/acute lung injury (ARDS/ALI). Because surgical patients may have been fundamentally different from the overall FACTT cohort, we set out to separately analyze the surgery patients in the trial. STUDY DESIGN We performed a posthoc, surgical subgroup analysis of 1,000 patients enrolled in the FACTT. Patients were randomized using a 2x2 factorial design comparing a conservative (CON) versus a liberal (LIB) strategy of fluid management and the use of a pulmonary artery catheter (PAC) or a central venous catheter (CVC). The primary end point was death at 60 days. Secondary end points included the number of ventilator-free days, ICU-free days, and dialysis-free days until hospital discharge up to day 90. We defined surgical patients as those admitted to a surgical ICU, burn ICU, or cardiac surgical ICU; trauma patients; or those with an APACHE III surgical admission type. RESULTS There were 244 surgical patients. Risk of death within 60 days of randomization did not vary with catheter or fluid management, and a corresponding lack of effect was evident with regard to dialysis-free days. Ventilator-free days were increased in the fluid-conservative group (LIB, 13+/-1 days; CON, 15+/-1 days; p=0.04) at 28 days. CVC patients had more ventilator-free days at 28 and 90 days (28 days: CVC, 16+/-1 days; PAC, 13+/-1 days; p=0.03; 90 days: CVC, 64+/-3 days; PAC, 57+/-4 days; p=0.03). CVC patients had more ICU-free days at 90 days (90 days: CVC, 63+/-3 days; PAC, 55+/-3 days; p=0.04). CONCLUSIONS The risk of death did not vary with fluid management or catheter. A conservative fluid-administration strategy and central venous catheter monitoring resulted in more ventilator-free and ICU-free days in surgical patients with acute lung injury, and conservative fluid administration did not result in more renal failure.

The appropriate diagnostic threshold for ventilator-associated pneumonia using quatititative cultures

BACKGROUND The use of quantitative cultures of the bronchoalveolar lavage (BAL) effluent to distinguish between posttraumatic inflammatory response and ventilator-associated pneumonia (VAP) is becoming more common. However, the diagnostic threshold of either 10 or 10 colonies/mL remains debatable. Because mortality from VAP is related to treatment delay, some have chosen a lower diagnostic threshold (>10 colonies/mL). This may result in unnecessary antibiotic use with its sequelae: increased resistant organisms, antibiotic-related complications, and increased costs. The purpose of this study is to determine the optimal diagnostic threshold for VAP diagnosis using quantitative cultures of the BAL effluent. METHODS Data on patients with fiberoptic bronchoscopy with BAL are maintained in a prospectively collected database at our Level I trauma center. This database was reviewed for timing and frequency of BAL and the colony counts of each organism identified. Indication for bronchoscopy was clinical evidence of VAP. VAP was defined as >10 colonies/mL in the BAL effluent. A false-negative BAL was defined as any patient who had <10 colonies/mL and developed VAP with the same organism up to 7 days after the previous culture. RESULTS Over a 46-month period, 526 patients underwent 1,372 fiberoptic bronchoscopy procedures with BAL. Of these, 72% were male patients, 91% followed blunt injury, and mean age and Injury Severity Score were 43 years and 30, respectively. Overall mortality was 14%. There were 1,898 organisms identified (42% were gram-positive and 58% were gram-negative). VAP was diagnosed in 38% of BAL. Overall, there were 43 episodes in 38 patients defined as false-negative (3%). The false-negative rate was 9% in patients with 10 organisms. The most common false-negative organisms were Pseudomonas and Acinetobacter species. CONCLUSION The VAP diagnostic threshold for quantitative BAL in trauma patients should be >10 colonies/mL. One may consider a threshold of >10 colonies/mL in severely injured patients with Pseudomonas or Acinetobacter species.

Improving Outcomes Following Penetrating Colon Wounds: Application Of A Clinical Pathway

IntroductionDuring World War II, failure to treat penetrating colon injuries with diversion could result in court martial. Based on this wartime experience, colostomy for civilian colon wounds became the standard of care for the next 4 decades. Previous work from our institution demonstrated that primary repair was the optimal management for nondestructive colon wounds. Optimal management of destructive wounds requiring resection remains controversial. To address this issue, we performed a study that demonstrated risk factors (pre or intraoperative transfusion requirement of more than 6 units of packed red blood cells, significant comorbid diseases) that were associated with a suture line failure rate of 14%, and of whom 33% died. Based on these outcomes, a clinical pathway for management of destructive colon wounds was developed. The results of the implementation of this pathway are the focus of this report. MethodsPatients with penetrating colon injury were identified from the registry of a level I trauma center over a 5-year period. Records were reviewed for demographics, injury characteristics, and outcome. Patients with nondestructive injuries underwent primary repair. Patients with destructive wounds but no comorbidities or large transfusion requirement underwent resection and anastomosis, while patients with destructive wounds and significant medical illness or transfusion requirements of more than 6 units/blood received end colostomy. The current patients (CP) were compared to the previous study (PS) to determine the impact of the clinical pathway. Outcomes examined included colon related mortality and morbidity (suture line leak and abscess). ResultsOver a 5.5-year period, 231 patients had penetrating colon wounds. 209 survived more 24 hours and comprise the study population. Primary repair was performed on 153 (73%) patients, and 56 patients had destructive injuries (27%). Of these, 40 (71%) had resection and anastomosis and 16 (29%) had diversion. More destructive injuries were managed in the CP group (27% vs. 19%). Abscess rate was lower in the CP group (27% vs. 37%), as was suture line leak rate (7% vs. 14%). Colon related mortality in the CP group was 5% as compared with 12% in the PS group. ConclusionsThe clinical pathway for destructive colon wound management has improved outcomes as measured by anastomotic leak rates and colon related mortality. The data demonstrated the need for colostomy in the face of shock and comorbidities. Institution of this pathway results in colostomy for only 7% of all colon wounds.

Oscope identifies oscillatory genes in unsynchronized single-cell RNA-seq experiments

Oscillatory gene expression is fundamental to development, but technologies for monitoring expression oscillations are limited. We have developed a statistical approach called Oscope to identify and characterize the transcriptional dynamics of oscillating genes in single-cell RNA-seq data from an unsynchronized cell population. Applying Oscope to a number of data sets, we demonstrated its utility and also identified a potential artifact in the Fluidigm C1 platform.

Antivenin and fasciotomy/debridement in the treatment of the severe rattlesnake bite

This experimental study of severe rattlesnake envenomation compares antivenin alone, fasciotomy and debridement alone, and a combination of the two methods as definitive treatment. Superior survival and preservation of muscle function were observed in the animals treated with antivenin alone.

The use of laparoscopic surgery in pregnancy: evaluation of safety and efficacy

BACKGROUND Laparoscopic surgery in pregnant women has become increasingly more common since the 1990s; however, the safety of laparoscopy in this population has been widely debated, particularly in emergent and urgent situations. METHODS A retrospective chart review of all pregnant women following a nonobstetric abdominal operation at a University hospital between 1993 and 2007. Perioperative morbidity and mortality for the mother and fetus were evaluated. RESULTS Ninety-four subjects were identified; 53 underwent laparoscopic procedures and 41 underwent open procedures. Cholecystectomy and appendectomy were performed in both groups with salpingectomy/ovarian cystectomy only in the laparoscopic group. No maternal deaths occurred, while fetal loss occurred in 3 cases within 7 days of the operation and in 1 case 7 weeks postoperatively. This and other perinatal complications occurred in 36.7% of the laparoscopic group and 41.7% of the open group. CONCLUSION Laparoscopic appendectomy and cholecystectomy appear to be as safe as the respective open procedures in pregnant patients; however, this population in particular remains at risk for perinatal complications regardless of the method of abdominal access.

Pediatric radiation exposure during the initial evaluation for blunt trauma.

BACKGROUND Increased utilization of computed tomography (CT) scans for evaluation of blunt trauma patients has resulted in increased doses of radiation to patients. Radiation dose is relatively amplified in children secondary to body size, and children are more susceptible to long-term carcinogenic effects of radiation. Our aim was to measure radiation dose received in pediatric blunt trauma patients during initial CT evaluation and to determine whether doses exceed doses historically correlated with an increased risk of thyroid cancer. METHODS A prospective cohort study of patients aged 0 years to 17 years was conducted over 6 months. Dosimeters were placed on the neck, chest, and groin before CT scanning to measure surface radiation. Patient measurements and scanning parameters were collected prospectively along with diagnostic findings on CT imaging. Cumulative effective whole body dose and organ doses were calculated. RESULTS The mean number of scans per patient was 3.1 ± 1.3. Mean whole body effective dose was 17.43 mSv. Mean organ doses were thyroid 32.18 mGy, breast 10.89 mGy, and gonads 13.15 mGy. Patients with selective CT scanning defined as ≤2 scans had a statistically significant decrease in radiation dose compared with patients with >2 scans. CONCLUSIONS Thyroid doses in 71% of study patients fell within the dose range historically correlated with an increased risk of thyroid cancer and whole body effective doses fell within the range of historical doses correlated with an increased risk of all solid cancers and leukemia. Selective scanning of body areas as compared with whole body scanning results in a statistically significant decrease in all doses.