Evert A. Eriksson

Surgical rib fixation for flail chest deformity improves liberation from mechanical ventilation

PURPOSE The goal of this study was to determine the impact of surgical rib fixation (SRF) in a treatment protocol for severe blunt chest trauma. MATERIALS AND METHODS Patients with flail chest admitted between September 2009 and June 2010 to our level I trauma center who failed traditional management and underwent SRF were matched with an historical group. Outcome variables evaluated include age, injury severity score, intensive care unit length of stay (LOS), hospital LOS, ventilator days, total number of rib fractures, and total number of segmental rib fractures. RESULTS The 2 groups were similar in age, injury severity score, intensive care unit LOS, hospital LOS, total number of rib fractures, and total segmental rib fractures. The operative group demonstrated a significant reduction in total ventilator days as compared with the nonsurgical group (4.5 [0-30] vs 16.0 [4-40]; P = .040). Patients with SRF were permanently liberated from the ventilator within a median of 1.5 days (0-8 days). CONCLUSIONS Surgical rib fixation resulted in a significant decrease in ventilator days and may represent a novel approach to decreasing morbidity in flail chest patients when used as a rescue therapy in patients with declining pulmonary status. Larger studies are required to further identify these benefits.

Safety and efficacy of heparin or enoxaparin prophylaxis in blunt trauma patients with a head abbreviated injury severity score >2

BACKGROUND Timing and type of chemoprophylaxis (CP) that should be used in patients with traumatic brain injury (TBI) remains unclear. We reviewed our institutions experience with low-molecular-weight heparin (LMWH) and unfractionated heparin (UFH) in TBI. METHODS The charts of all TBI patients with a head abbreviated injury severity score >2 (HAIS) and an intensive care unit length of stay >48 hours admitted during a 42-month period between 2006 and 2009 were reviewed. CP was initiated after intracranial hemorrhage was considered stable. We reviewed all operative notes and radiologic reports in these patients to analyze the rate of significant intracranial hemorrhagic complications, deep venous thrombosis, or pulmonary embolus. RESULTS A total of 386 patients with TBI were identified; 158 were treated with LMWH and 171 were treated with UFH. HAIS was significantly different between the LMWH (3.8 ± 0.7) and UFH (4.1 ± 0.7) groups; the time to initiation of CP was not. The UFH group had a significantly higher rate of deep venous thrombosis and pulmonary embolus. Progression of ICH that occurred after the initiation of CP was significantly higher in the UFH-treated patients (59%) when compared with those treated with LMWH (40%). Two patients in the UFH group required craniotomy after the initiation of CP. CONCLUSION LMWH is an effective method of CP in patients with TBI, providing a lower rate of venous thromboembolic and hemorrhagic complications when compared with UFH. A large, prospective, randomized study would better evaluate the safety and efficacy of LMWH in patients suffering blunt traumatic brain injury.

Cerebral perfusion pressure and intracranial pressure are not surrogates for brain tissue oxygenation in traumatic brain injury.

OBJECTIVE Utilization of brain tissue oxygenation (pBtO(2)) is an important but controversial variable in the treatment of traumatic brain injury (TBI). We evaluated the correlation between pBtO(2)/CPP and pBtO(2)/ICP and determined the parameter most closely related to survival. METHODS Consecutive, adult patients with severe TBI and pBtO(2) monitors were retrospectively identified. Time-indexed measurements of pBtO(2), CPP and ICP were collected and correlation coefficients were determined. Patients were then stratified according to survival and pBtO(2), CPP and ICP values were compared between groups. RESULTS There were 4169 time-indexed data points (i.e., pBtO(2) with respective CPP and ICP values) in 15 patients. The cohort consisted of a mean age of 37±17 years, ISS of 27±7 and GCS of 4.5±1.5. Survival was 53% (8/15). In a normal regression models, neither the ICP (p=0.58) nor the CPP (p=0.71) predict pBtO(2) significantly. There was a significant difference in pBtO(2) in survivors (31.5±3.1 vs. 25.2±4.8, p=0.010) but not in CPP or ICP. Survivors had a lower proportion of time with pBtO(2)<25 mmHg [20% (3.4-44.6) vs. 40% (16.2-89), p=0.049]. In contrast, survivors had a greater proportion of time with CPP<70 and no difference in the proportion of time with and ICP>20. CONCLUSIONS CPP and ICP should not be used as surrogates for pBtO(2) since cerebral oxygenation varies independently of cerebral hemodynamics and pressures. Brain tissue oxygen monitoring in patients with TBI provides unique information regarding cerebral oxygenation the utility of which remains to be fully described. SIGNIFICANCE CPP and ICP are not surrogates for pBtO(2). Brain tissue oxygenation monitoring provides unique information for the treatment of traumatically injured patients.

Blunt abdominal aortic injury: A Western Trauma Association multicenter study

BACKGROUND Blunt abdominal aortic injury (BAAI) is a rare injury. The objective of the current study was to examine the presentation and management of BAAI at a multi-institutional level. METHODS The Western Trauma Association Multi-Center Trials conducted a study of BAAI from 1996 to 2011. Data collected included demographics, injury mechanism, associated injuries, interventions, and complications. RESULTS Of 392,315 blunt trauma patients, 113 (0.03%) presented with BAAI at 12 major trauma centers (67% male; median age, 38 years; range, 6–88; median Injury Severity Score [ISS], 34; range, 16–75). The leading cause of injury was motor vehicle collisions (60%). Hypotension was documented in 47% of the cases. The most commonly associated injuries were spine fractures (44%) and pneumothorax/hemothorax (42%). Solid organ, small bowel, and large bowel injuries occurred in 38%, 35%, and 28% respectively. BAAI presented as free aortic rupture (32%), pseudoaneurysm (16%), and injuries without aortic external contour abnormality on computed tomography such as large intimal flaps (34%) or intimal tears (18%). Open and endovascular repairs were undertaken as first-choice therapy in 43% and 15% of cases, respectively. Choice of management varied by type of BAAI: 89% of intimal tears were managed nonoperatively, and 96% of aortic ruptures were treated with open repair. Overall mortality was 39%, the majority (68%) occurring in the first 24 hours because of hemorrhage or cardiac arrest. The highest mortality was associated with Zone II aortic ruptures (92%). Follow-up was documented in 38% of live discharges. CONCLUSION This is the largest BAAI series reported to date. BAAI presents as a spectrum of injury ranging from minimal aortic injury to aortic rupture. Nonoperative management is successful in uncomplicated cases without external aortic contour abnormality on computed tomography. Highest mortality occurred in free aortic ruptures, suggesting that alternative measures of early noncompressible torso hemorrhage control are warranted. LEVEL OF EVIDENCE Epidemiologic study, level III; therapeutic study, level IV.

The first 72 hours of brain tissue oxygenation predicts patient survival with traumatic brain injury.

BACKGROUND: Utilization of brain tissue oxygenation (pBtO2) is an important but controversial variable in the treatment of traumatic brain injury. We hypothesize that pBtO2 values over the first 72 hours of monitoring are predictive of mortality. METHODS: Consecutive, adult patients with severe traumatic brain injury and pBtO2 monitors were retrospectively identified. Time-indexed measurements of pBtO2, cerebral perfusion pressure (CPP), and intracranial pressure (ICP) were collected, and average values over 4-hour blocks were determined. Patients were stratified according to survival, and repeated measures analysis of variance was used to compare pBtO2, CPP, and ICP. The pBtO2 threshold most predictive for survival was determined. RESULTS: There were 8,759 time-indexed data points in 32 patients. The mean age was 39 years ± 16.5 years, injury severity score was 27.7 ± 10.7, and Glasgow Coma Scale score was 6.6 ± 3.4. Survival was 68%. Survivors consistently demonstrated higher pBtO2 values compared with nonsurvivors including age as a covariate (F = 12.898, p < 0.001). Individual pBtO2 was higher at the time points 8 hours, 12 hours, 20 hours to 44 hours, 52 hours to 60 hours, and 72 hours of monitoring (p < 0.05). There was no difference in ICP (F = 1.690, p = 0.204) and CPP (F = 0.764, p = 0.389) values between survivors and nonsurvivors including age as a covariate. Classification and regression tree analysis identified 29 mm Hg as the threshold at which pBtO2 was most predictive for mortality. CONCLUSION: The first 72 hours of pBtO2 neurologic monitoring predicts mortality. When the pBtO2 monitor remains below 29 mm Hg in the first 72 hours of monitoring, mortality is increased. This study challenges the brain oxygenation threshold of 20 mm Hg that has been used conventionally and delineates a time for monitoring pBtO2 that is predictive of outcome. LEVEL OF EVIDENCE: III, prognostic study.

Applicability of the National Healthcare Safety Network's surveillance definition of ventilator-associated events in the surgical intensive care unit: A 1-year review

BACKGROUND In 2012, the National Healthcare Safety Network presented a new surveillance definition for ventilator-associated events (VAEs) to objectively define worsening pulmonary status in ventilated patients. VAE subcategories, ventilator-associated condition (VAC), infection-related VAC, and probable ventilator-associated pneumonia (PrVAP), were vetted predominantly in medical intensive care units. Our goal was to evaluate how well VAE criteria characterize pulmonary complications in surgical intensive care unit (SICU) patients. METHODS Since September 2012, all intubated SICU patients were screened prospectively for VAE and monitored for sustained respiratory dysfunction that did not meet VAE criteria. We diagnosed ventilator-associated pneumonia (VAP) using a clinical definition: Clinical Pulmonary Infection Score (CPIS) greater than 6 and catheter-directed bronchoalveolar lavage cultures with 104 or more colony-forming units per milliliter of pathogenic organisms. RESULTS We admitted 704 intubated patients. A total of 437 were intubated for two or more days (mean [SD], age 46 [18] years; 65% male; median ventilator days, 4 [range, 2–9]; median Sequential Organ Failure Assessment [SOFA] score, 8 [range, 5–10]). Using VAE criteria, we identified 37 patients with VAC, 31 with infection-related VAC, and 22 with PrVAP. While the remaining 400 patients did not meet VAE criteria, we identified 111 patients (28%) with respiratory deterioration and diagnosed 99 additional pneumonias. Of the 111 patients, 85 (77%) never had a period of stable/decreasing oxygenation, requiring elevated vent settings upon initiation of ventilation preventing them from meeting VAE criteria. Of the 99 pneumonia patients, 10% had sustained respiratory deterioration treated with elevations in mean airway pressure; they did not meet VAE criteria as the positive end-expiratory pressure or FIO2 was not elevated. Twenty-seven percent never had a period of stable/decreasing oxygenation. Fifty-eight percent had less than 2 days of respiratory deterioration. Agreement between PrVAP and clinical VAP was 77.3% (&kgr; = 0.243, p < 0.001). CONCLUSION The applicability of the new National Healthcare Safety Network categories of VAE to critically ill surgery patients is limited. Agreement between PrVAP and clinical VAP in SICU patients is poor. Most surgical patients are not well categorized by this new definition; a better method of surveillance should be created for this patient population. LEVEL OF EVIDENCE Diagnostic study, level III.

Cerebral fat embolism without intracardiac shunt: A novel presentation

Fat embolism syndrome (FES) is defined as an uncommon life-threatening disease process consisting of pulmonary, central nervous system (CNS), and cutaneous manifestations. The pathophysiology of this secondary injury is poorly understood. In the setting of the multiply injured patient, the diagnosis of FES is difficult to ascertain. A case report of a posttraumatic death caused by acute dissemination of diffuse fat emboli to the brain and lungs in the absence of a right-to-left heart defect after femur fracture is presented. The transesophageal echo cardiogram with bubble study failed to demonstrate an intracardiac defect or AV malformation in the lung further supporting a biochemical process. The acute decompensation of the patient within 2 h of the injury would favor mechanical emboli. Supportive care continues to be the mainstay of treatment for FES. Cerebral fat embolism should be considered in traumatically injured patients with unexplained decline in their neurologic examination. Cerebral fat embolism may occur without an intracardiac shunt.

Tight blood glucose control in trauma patients: Who really benefits?

Background: This study was designed to evaluate the effect of intensive insulin control (IIT) on outcomes for traumatically injured patients as a function of injury severity score (ISS) and age. Patients and Methods: A retrospective review of 2028 adult trauma patients admitted to the surgical intensive care unit (SICU) in a Level I trauma center was performed. Data were collected from a 48-month period before (Pre-IIT) (goal blood glucose 80–200 mg/dL) and after (Post-IIT) (goal blood glucose level 80–110 mg/dL), an IIT protocol was initiated. Patients were stratified by age and ISS. The primary endpoint was mortality. Results: There were 784 Pre-IIT and 1244 Post-IIT patients admitted. There was no significant difference between Pre-IIT vs. Post-IIT for the mechanism of injury or ISS. Values for the Pre-IIT group were significantly higher for mortality (21.5% vs. 14.7%, P<0.001) and hospital, but not ICU length of stay were decreased. A significant improvement in mortality was demonstrated between Pre-IIT vs. Post-IIT stratified within the age groups of 41–50, 51–60, and 61 but not the groups 18–30 and 31–40. Mean glucose levels (mg/dL) decreased significantly after the institution of IIT (144.7±1.4 vs. 130.9±0.9; P<0.001). In addition, the occurrence per patient of blood glucose levels <40 mg/dL increased (0.77% vs. 2.86%; P=0.001) and blood glucose levels greater than 200 mg/dL was similar (39.1% vs. 38.8%; P=0.892) in the Pre-IIT and Post-IIT groups, respectively. Glycemic variability, reflected by the standard deviation of each patients mean glucose level during ICU stay, as well as mean glucose level were lower in survivors than in nonsurvivors. Finally, multivariable logistic regression analysis identified both mean glucose level and glycemic variability as independent contributors to the risk of mortality. Conclusions: The implementation of IIT has been associated with a decrease in both hospital length of stay as well as mortality. Average glucose value and glucose variability are independent predictors of survival. Trauma patients with moderate, severe, and very severe injuries benefit most from IIT. These observational data suggest that patients over 40 years of age benefited a great deal more than their younger counterparts from IIT. This study supports the need for a randomized controlled trial to investigate the role of IIT in traumatically injured patients.

Cervical Spine Injuries and Helmet Laws: A Population-Based Study

BACKGROUND: To assess the incidence of cervical spine (C-spine) injuries in patients admitted after motorcycle crash in states with mandatory helmet laws (MHL) compared with states without helmet laws or selective helmet laws. METHODS: The Nationwide Inpatient Sample from the Healthcare and Utilization Project for the year 2008 was analyzed. International Classification of Diseases and Health Related Problems, Ninth Edition codes were used to identify patients with a diagnosis of motorcycle crash and C-spine injuries. National estimates were generated based on weighted analysis of the data. Outcome variables investigated were as follows: length of stay (LOS), in-hospital mortality, hospital teaching status, and discharge disposition. States were then stratified into states with MHL or selective helmet laws. RESULTS: A total of 30,117 discharges were identified. Of these, 2,041 (6.7%) patients had a C-spine injury. Patients in MHL states had a lower incidence of C-spine injuries (5.6 vs. 6.4%; p = 0.003) and less in-hospital mortality (1.8 vs. 2.6%; p = 0.0001). Patients older than 55 years were less likely to be discharged home (57.5% vs. 72.5%; p = 0.0001), more likely to die in-hospital (3.0% vs. 2.1%; p = 0.0001), and more likely to have a hospital LOS more than 21 days (7.7% vs. 6.2%; p = 0.0001). CONCLUSION: Patients admitted to the hospital in states with MHLs have decreased rate of C-spine injuries than those patients admitted in states with more flexible helmet laws. Patients older than 55 years are more likely to die in the hospital, have a prolonged LOS, and require services after discharge. LEVEL OF EVIDENCE: III.

Early nonbronchoscopic bronchoalveolar lavage: predictor of ventilator-associated pneumonia?

BACKGROUND Ventilator-associated pneumonia is a problem in trauma and emergency general surgery patients. Our hospital-acquired infection prevention committee approved the use of early nonbronchoscopic bronchoalveolar lavage (screening-BAL) in the surgical intensive care unit (SICU) to identify ventilated patients with bronchiolar bacteria before 48 hours. We reviewed the results of this quality improvement initiative. METHODS All ventilated patients in the SICU (March 2011 to June 2012) underwent a screening-BAL 36 hours to 48 hours after intubation; quantitative culture results (>5 × 104 colony-forming unit per milliliter) were used to identify positive specimens. Clinical pneumonia was defined as clinical pulmonary infection score greater than 6 with a subsequent positive diagnostic-BAL result. Sequential organ failure assessment scores were averaged for the first 48 hours in the SICU. Continuous and dichotomous data were compared, and a multivariate regression analysis was performed on the screening-BAL and pneumonia results. RESULTS Screening-BALs were performed in 150 patients (99 trauma and 51 emergency general surgery patients), 72 of these specimens had positive findings. Fifty-three clinical pneumonias were diagnosed, and 45 (positive predictive value, 0.85) identified the same organism as the screening-BAL. Clinical pneumonia developed in eight patients with a negative screening-BAL (negative predictive value, 0.85). Antibiotic therapy at the time of the screening-BAL was associated with a negative screen (odds ratio, 0.44; p = 0.026). Pneumonia developed on median postintubation Day 4 (2–15 days) in patients with a positive screening-BAL results as compared with day 7.5 in the patients with a negative screening-BAL results (3.5–15 days; p = 0.007). Field intubation is an independent risk factor (odds ratio, 3.5; p = 0.004). CONCLUSION Positive screening-BAL results in trauma and emergency general surgery patients are associated with the development of ventilator-associated pneumonia by the same organism and may play a role in identifying patients at risk for pneumonia. Further studies must be conducted to evaluate the role of screening-BAL in this patient population. LEVEL OF EVIDENCE Diagnostic/prognostic study, level III.