Tiffany K. Bee

Blunt cerebrovascular injuries: diagnosis and treatment.

BACKGROUND Blunt cerebrovascular injuries (BCVIs), once thought to be rare, have been recognized with increasing frequency in recent years. An incidence of 0.33% for carotid artery injury (CAI) was noted from our institution, with 24% stroke-related mortality. Vertebral artery injury (VAI) has been thought both rare and of questionable significance. Incidence, associated injury patterns, and outcomes were examined during a period of aggressive screening (four-vessel angiography). METHODS Patients with BCVI were identified from the registry of a Level I trauma center over a 5-year period (1995-1999). RESULTS One hundred thirty-nine BCVIs were identified in 96 patients: 75 were CAIs (14 bilateral), 64 were VAIs (14 bilateral), and 15 patients had both CAI and VAI. The incidence of CAI was 0.5% of all blunt trauma admissions, significantly higher than our earlier experience (p < 0.0002), whereas that for VAI was 0.4%. Thirty-four percent of CAIs were diagnosed because of ischemic changes and 38% because of injury pattern (neck, Horner syndrome, basilar skull fracture); only 12% of VAIs were diagnosed because of posterior circulation ischemia, with 64% because of injury pattern (cervical spine, soft tissue, facial fracture). Stroke-related mortality for CAI was 13%, and that for VAI was 4%. Forty-three of the 75 CAIs were treated (anticoagulation/antiplatelet) before development of ischemia. Thirty-nine of the 50 VAI patients were treated before development of ischemia. Stroke rate for CAI was 31% (hemiplegia/hemiparesis) and for VAI was 14% (brain stem dysfunction). Stroke rate for treated vessels (heparin, antiplatelet therapy) with CAI was 6.8% compared with 64% in untreated vessels (p < 0.001). Treated patients with VAI had a stroke rate of 2.6%, whereas untreated patients developed stroke 54% of the time. CONCLUSION Increased awareness and aggressive screening have resulted in significantly increased incidence of diagnosis of CAI, with associated lower stroke-related mortality. VAIs have been noted with similar incidence, and though the stroke rate is lower with VAI, stroke outcomes are generally catastrophic. Anticoagulation therapy is effective for both varieties of BCVI.

Staged Management of Giant Abdominal Wall Defects: Acute and Long-Term Results

Introduction Shock resuscitation leads to visceral edema often precluding abdominal wall closure. We have developed a staged approach encompassing acute management through definitive abdominal wall reconstruction. The purpose of this report is to analyze our experience with this technique applied to the treatment of patients with open abdomen and giant abdominal wall defects. Methods Our management scheme for giant abdominal wall defects consists of 3 stages: stage I, absorbable mesh insertion for temporary closure (if edema quickly resolves within 3–5 days, the mesh is gradually pleated, allowing delayed fascial closure); stage II, absorbable mesh removal in patients without edema resolution (2–3 weeks after insertion to allow for granulation and fixation of viscera) and formation of the planned ventral hernia with either split thickness skin graft or full thickness skin closure over the viscera; and stage III, definitive reconstruction after 6–12 months (allowing for inflammation and dense adhesion resolution) by using the modified components separation technique. Consecutive patients from 1993 to 2001 at a single institution were evaluated. Outcomes were analyzed by management stage, with emphasis on wound related morbidity and mortality, and fistula and recurrent hernia rates. Results Two hundred seventy four patients (35 with sepsis, 239 with hemorrhagic shock) were managed. There were 212 males (77%), and mean age was 37 (range, 12–88). The average size of the defects was 20 × 30 cm. In the stage I group, 108 died (92% of all deaths) because of shock. The remaining 166 had temporary closure with polyglactin 910 woven absorbable mesh. As visceral edema resolved, bedside pleating of the absorbable mesh allowed delayed fascial closure in 37 patients (22%). In the stage II group, 9 died (8% of all deaths) from multiple organ failure associated with their underlying disease process, and 96% of the remaining 120 had split-thickness skin graft placed over the viscera. No wound related mortality occurred. There were a total of 14 fistulae (5% of total, 8% of survivors). In the stage III group, to date, 73 of the 120 have had definitive abdominal wall reconstruction using the modified components separation technique. There were no deaths. Mean follow-up was 24 months, (range 2–60). Recurrent hernias developed in 4 of these patients (5%). Conclusions The staged management of patients with giant abdominal wall defects without the use of permanent mesh results in a safe and consistent approach for both initial and definitive management with low morbidity and no technique-related mortality. Absorbable mesh provides effective temporary abdominal wall defect coverage with a low fistula rate. Because of the low recurrent hernia rate and avoidance of permanent mesh, the components separation technique is the procedure of choice for definitive abdominal wall reconstruction.

ARDS after pulmonary contusion: accurate measurement of contusion volume identifies high-risk patients.

BACKGROUND The pathophysiology of pulmonary contusion (PC) is poorly understood, and only minimal advances have been made in management of this entity over the past 20 years. Improvement in understanding of PC has been hindered by the fact that there has been no accurate way to quantitate the amount of pulmonary injury. With this project, we examine a method of accurately measuring degree of PC by quantifying contusion volume relative to pulmonary function and outcome. METHODS Patients with PC from isolated chest trauma who had admission chest computed tomographic scan were identified from the registry of a Level I trauma center over a 1.5-year period. Subsequently, prospective data on all patients admitted to the intensive care unit with PC during a 5-month period were collected and added to the retrospective database. Using computer-generated three-dimensional reconstruction from admission chest computed tomographic scan, contusion volume was measured and expressed as a percentage of total lung volume. Admission pulmonary function variables (Pao2/FiO2, static compliance), injury descriptors (chest Abbreviated Injury Score, Injury Severity Score, injury distribution), and indicators of degree of shock (admission systolic blood pressure, admission base deficit) were documented. Outcomes included maximum positive end-expiratory pressure, ventilator days, pneumonia, and acute respiratory distress syndrome (ARDS). RESULTS Forty-nine patients with PC (35 bilateral) were identified. The average severity of contusion was 18% (range, 5-55%). Patients were classified using contusion volume as severe PC (> or =20%, n = 17) and moderate PC (< 20%, n = 32). Injury Severity Score was similar in the severe and moderate groups (23.3 vs. 26.5, p = 0.33), as were admission Glasgow Coma Scale score (12 vs. 13, p = 0.30), admission blood pressure (131 vs. 129 mm Hg, p = 0.90), and admission Pao2/Fio2 (197 vs. 255, p = 0.14). However, there was a much higher rate of ARDS in the severe group as compared with the moderate group (82% vs. 22%, p < 0.001). There was a trend toward higher pneumonia rate in the severe group, with 50% of patients in the severe group developing pneumonia as compared with 28% in the moderate group (p = 0.20). CONCLUSION Extent of contusion volumes measured using three-dimensional reconstruction allows identification of patients at high risk of pulmonary dysfunction as characterized by development of ARDS. This method of measurement may provide a useful tool for the further study of PC as well as for the identification of patients at high risk of complications at whom future advances in therapy may be directed.

Temporary abdominal closure techniques: a prospective randomized trial comparing polyglactin 910 mesh and vacuum-assisted closure.

OBJECTIVE The options for abdominal coverage after damage control laparotomy or abdominal compartment syndrome vary by institution, surgeon preference, and type of patient. Some advocate polyglactin mesh (MESH), while others favor vacuum-assisted closure (VAC). We performed a single institution prospective randomized trial comparing morbidity and mortality differences between MESH and VAC. METHODS Patients expected to survive and requiring open abdomen management were prospectively randomized to either MESH or VAC. After randomization, an enteral feeding tube was inserted and the closure device placed. VAC patients returned to the operating room every 3 days for a total of three changes at which time polyglactin mesh was placed if closure was not possible. The MESH group had twice daily assessments for the possibility of bedside mesh cinching and closure. Both groups underwent split thickness skin grafting when granulation tissue was evident, if delayed primary closure was not possible. RESULTS Fifty-one patients were randomized. Both cohorts were matched for Injury Severity Scale score, gender, blunt/penetrating/abdominal compartment syndrome and age. Three patients died within 7 days and were excluded from closure rate calculation. There were no differences between delayed primary fascial closure rates in the VAC (31%) or MESH (26%) groups. The fistula rate in the VAC group was 21% but not statistically different from the 5% rate for MESH. Intraabdominal rates were not statistically different. All VAC fistulas were related to feeding tubes and suture line areas; the MESH fistula followed a retroperitoneal colon leak remote from the mesh. CONCLUSIONS MESH and VAC are both useful methods for abdominal coverage, and are equally likely to produce delayed primary closure. The fistula rate for VAC is most likely due to continued bowel manipulation with VAC changes with a feeding tube in place-enteral feeds should be administered via nasojejunal tube. Neither method precludes secondary abdominal wall reconstruction.

Does Optimal Timing for Spine Fracture Fixation Exist

ObjectiveTo evaluate the effect of timing of spine fracture fixation on outcome in multiply injured patients. Summary Background DataThere is little consensus regarding the optimal timing of spine fracture fixation after blunt trauma. Potential advantages of early fixation include earlier patient mobilization and fewer septic complications; disadvantages include compounded complications from associated injuries and inconvenience of surgical scheduling. MethodsPatients with spine fractures from blunt trauma admitted to an urban level 1 trauma center during a 42-month period who required surgical spine fracture fixation were identified from the registry. Patients were analyzed according to timing of fixation, level of spine injury, and impact of associated injuries (measured by injury severity score). Early fixation was defined as within 3 days of injury, and late fixation was after 3 days. Outcomes analyzed were intensive care unit and hospital stay, ventilator days, pneumonia, survival, and hospital charges. ResultsTwo hundred ninety-one patients had spine fracture fixation, 142 (49%) early and 149 (51%) late. Patients were clinically similar relative to age, admission blood pressure, injury severity score, and chest abbreviated injury scale score. The intensive care unit stay was shorter for patients with early fixation. The incidence of pneumonia was lower for patients with early fixation. Charges were lower for patients with early fixation. Patients were stratified by level of spine injury. There were 163 cervical (83 early, 80 late), 79 thoracic (30 early, 49 late), and 49 lumbar fractures (29 early, 20 late). There were no differences in injury severity between early and late groups for each fracture site. The most striking differences occurred in the thoracic fracture group. Early fixation was associated with a lower incidence of pneumonia, a shorter intensive care unit stay, fewer ventilator days, and lower charges. High-risk patients had lower pneumonia rates and less hospital resource utilization with early fixation. ConclusionsEarly spine fracture fixation is safely performed in multiply injured patients. Early fixation is preferred in patients with thoracic spine fractures because it allows earlier mobilization and reduces the incidence of pneumonia. Although delaying fixation in the less severely injured may be convenient for scheduling, it increases hospital resource utilization and patient complications.

Associated injuries in blunt solid organ trauma: implications for missed injury in nonoperative management.

BACKGROUND During the past decade, nonoperative management (NOM) of hemodynamically stable blunt trauma patients with liver (L) or spleen (S) injury has become the standard of care. This trend has led to concerns over missed associated intra-abdominal injuries with concomitant morbidity. To better understand the incidence and risk of missed injury, patterns of associated intra-abdominal injury were examined in all patients with blunt liver and spleen injuries, and missed injuries were reviewed in patients undergoing NOM. METHODS Patients were identified from the registry of a Level I trauma center over a 3-year period. Records were reviewed for demographics, injury characteristics, and associated injuries. Indications for primary operation were hemodynamic instability or significant associated intra-abdominal injury. Missed injury was defined as unsuspected intra-abdominal injury requiring laparotomy in patients otherwise undergoing NOM for liver or spleen injury. RESULTS Eight hundred three patients (338 in the L group, 345 in the S group, and 120 in the L + S group) were treated between December 1995 and December 1998. Rates of planned NOM were 89% (L group), 78% (S group), and 75% (L + S group). On examination of all patients with blunt liver or spleen injuries, the incidence of associated intra-abdominal injury was higher in the L group at 5% as compared with 1.7% in the S group (p = 0.02). The associated intra-abdominal injury rate in the L + S group was similar to the L group at 4.2%. Although in the L and S groups, rates of diaphragm (0.5% vs. 1%, p = 0.45) and intra-abdominal bladder injury (0.3% vs. 0.3%, p = 0.99) were similar, bowel injury was more common in the L group (11% vs. 0%, p = 0.0004), as was pancreatic injury (7% vs. 0%, p = 0.007). In NOM patients, missed injury occurred in seven (2.3%) L patients versus zero S patients (p = 0.012). No L + S patient had unexpected injuries. Missed injuries included two small bowel, three diaphragm, one pancreas, and one mesenteric tear. CONCLUSION Damage to the pancreas and bowel is significantly associated with liver as opposed to spleen injuries. Actual missed intra-abdominal injury with NOM mirrors this pattern, occurring more often with liver than with spleen injuries. However, the overall incidence of missed injury is quite low, and should not influence decisions concerning eligibility for NOM. We speculate that the greater amount and/or different vector of energy transfer needed to injure the liver versus the spleen accounts for the greater rate of associated injuries to the pancreas/small bowel.

Failures of splenic nonoperative management: is the glass half empty or half full?

BACKGROUND Published contraindications to nonoperative management (NOM) of blunt splenic injury (BSI) include age > or = 55, Glasgow Coma Scale score < or = 13, admission blood pressure < 100 mm Hg, major (grades 3-5) injuries, and large amounts of hemoperitoneum. Recently reported NOM rates approximate 60%, with failure rates of 10% to 15%. This study evaluated our failures of NOM for BSI relative to these clinical factors. METHODS All patients with BSI at a Level I trauma center over a 46-month period ending September 1999 were reviewed. Failures of NOM included patients initially selected for NOM who subsequently required splenectomy/splenorrhaphy. RESULTS Five hundred fifty-eight had BSI. Twenty-three percent (128) underwent emergent laparotomy for hemodynamic instability and 77% (430) were observed. The NOM failure rate was only 8%. Univariate analysis identified moderate to large hemoperitoneum (p < 0.03), grades 3 to 5 (p < 0.004), and age > or = 55 (p < 0.0006) as being significantly associated with failure. Multivariate analysis identified age > or = 55 and grades 3 to 5 injuries as independent predictors of failure. The highest failure rates (30-40%) occurred in patients age > or = 55 with major injury for moderate to large hemoperitoneum. Mortality rates for successful NOM were 12%, and 9% for failed NOM. CONCLUSION Inclusion of all high-risk patients increased the NOM rate while maintaining a low failure rate. Although age > or = 55 and major BSI were independently associated with failure of NOM, approximately 80% of these high-risk patients were successfully managed nonoperatively. There was no increased mortality associated with failure. Although these factors may indeed predict failure, they do not necessarily contraindicate NOM.

Open abdominal management after damage-control laparotomy for trauma: A prospective observational American Association for the Surgery of Trauma multicenter study

BACKGROUND We conducted a prospective observational multi-institutional study to examine the natural history of the open abdomen (OA) after trauma and identify risk factors for failure to achieve definitive primary fascial closure (DPC) after OA use in trauma. METHODS Adults requiring OA for trauma were enrolled during a 2-year period. Demographics, presentation, and management variables were used to compare primary fascial closure and non–primary fascial closure patients, with logistic regression used to identify independent risk factors for failure to achieve primary fascial closure. RESULTS A total of 572 patients from 14 American College of Surgeons–verified Level I trauma centers were enrolled. The majority were male (79%), mean (SD) age 39 (17) years. Injury Severity Score (ISS) was 15 or greater in 85% of patients and 84% had an abdominal Abbreviated Injury Scale (AIS) score of 3 or greater. Overall mortality was 23%. Initial primary fascial closure with unaltered native fascia was achieved in 379 patients (66%). Patients surviving at least 48 hours were grouped into those achieving DPC and those who did not achieve DPC after OA use. After logistic regression, independent risk factors for failure to achieve DPC included the number of reexplorations required (adjusted odds ratio [AOR], 1.3; 95% confidence interval (CI), 1.2–1.6; p < 0.001) the development of intra-abdominal abscess/sepsis (AOR, 2.4; 95% CI, 1.2–4.8; p = 0.011) bloodstream infection (AOR, 2.6; 95% CI, 1.2–5.7; p = 0.017), acute renal failure (AOR, 2.3; 95% CI, 1.2–5.7; p = 0.007), enteric fistula (AOR, 6.4; 95% CI, 1.2–32.8; p = 0.010) and ISS of greater than 15 (AOR, 2.5; 95% CI, 1.1–5.9; p = 0.037). CONCLUSION Our study identifies independent risk factors associated with failure to achieve primary fascial closure during initial hospitalization after OA use for trauma. Additional study is required to validate appropriate algorithms that optimize the opportunity to achieve primary fascial closure and outcomes in this population. LEVEL OF EVIDENCE Prognostic study, level III.

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.

Multiplicity of solid organ injury: influence on management and outcomes after blunt abdominal trauma.

OBJECTIVE The current study was undertaken to examine how concomitant injury to liver and spleen after blunt abdominal trauma affects management and outcomes. METHODS This study was a retrospective chart review of all blunt abdominal trauma patients admitted with a diagnosis of liver or spleen injury at two Level I trauma centers over a 4-year period. Presentation, injury grade, management, and outcomes were analyzed. Patients with single-organ injury (liver or spleen) were compared with patients having injury to both organs (liver and spleen). Significance was set at 95% confidence intervals. RESULTS Of 1,288 patients who met entry criteria, 1,125 had single (spleen, 573; liver, 552) organ injury (group S) and 163 had injury to both organs (group B). Group B patients had significantly higher Injury Severity Score, higher admission lactate, and lower admission systolic blood pressure and base excess. Eighty-one percent (915 of 1,125) of group S and 69% (112 of 163) of group B patients were managed nonoperatively (p < 0.05). Of the nonoperatively managed patients, 5.8% (53 of 915) in group S and 11.6% (13 of 112) in group B failed this form of therapy (p < 0.05). Higher failure rate in group B was because of bleeding from injured solid organ(s), and not non-solid organ related failures. Mortality, intensive care unit and hospital lengths of stay, and transfusion requirements were all significantly higher in group B. CONCLUSION Blunt trauma patients with concomitant injury to liver and spleen have higher Injury Severity Score, mortality, lengths of stay, and transfusion requirements. There is a higher failure rate with nonoperative management, and therefore extra vigilance is warranted when choosing this form of therapy in the presence of injury to both organs.