Lucy Z. Kornblith

One Thousand Bedside Percutaneous Tracheostomies in the Surgical Intensive Care Unit: Time to Change the Gold Standard

BACKGROUND Bedside percutaneous tracheostomy (BPT) is a cost-effective alternative to open tracheostomy. Small series have consistently documented minimal morbidity, but BPT has yet to be embraced as the standard of care. Because this has been our preferred technique in the surgical ICU for more than 20 years, we reviewed our experience to ascertain its safety. We hypothesize that BPT has acceptably minimal morbidity, even in high-risk patients. STUDY DESIGN Patients undergoing BPT from January 1998 to June 2008 were reviewed. High-risk patients were defined as those with cervical collar or halo, cervical spine injuries, systemic heparinization, positive end-expiratory pressure >10 cm H(2)O or fraction of inspired oxygen > 50%. RESULTS During the study period, 1,000 patients underwent BPT (74% men; mean ± SEM age 46 ± 0.6 years; 70% trauma). BPT was performed 8.9 ± 0.2 days (mean ± SEM) after admission. Patients remained ventilator dependent for an additional 9.7 ± 0.4 days (mean ± SEM). There were 482 (48%) patients undergoing BPT who were considered high-risk: 1 risk category, 273 patients; 2 risk categories, 139 patients; 3 risk categories, 56 patients; 4 risk categories, 12 patients; 5 risk categories, 2 patients. Complications occurred in 14 (1.4%) patients. Early complications included tracheostomy tube misplacement requiring revision (n = 4), bleeding requiring intervention (n = 2), infection (n = 1), and procedure failure requiring cricothyroidotomy (n = 1). Late complications included persistent stoma requiring operative closure (n = 4) and subglottic stenosis (n = 2). There were 6 complications (1.2%) in normal risk and 8 complications (1.7%) in high-risk patients. There were no deaths related to BPT. CONCLUSIONS BPT in the surgical intensive care unit is a safe procedure, even in high-risk patients. We believe BPT is the new gold standard for patients requiring tracheostomy for mechanical ventilation.

A paradigm shift in trauma resuscitation: evaluation of evolving massive transfusion practices.

IMPORTANCE The evolution of damage control strategies has led to significant changes in the use of resuscitation after traumatic injury. OBJECTIVE To evaluate changes in the administration of fluids and blood products, hypothesizing that a reduction in crystalloid volume and a reduced red blood cell (RBC) to fresh frozen plasma (FFP) ratio over the last 7 years would correlate with better resuscitation outcomes. DESIGN Observational prospective cohort study. SETTING Urban level I trauma center. PARTICIPANTS A total of 174 trauma patients receiving a massive transfusion (>10 units of RBCs in 24 hours) or requiring the activation of the institutional massive transfusion protocol from February 2005 to June 2011. EXPOSURE Patients had to either receive a massive transfusion or require the activation of the institutional massive transfusion protocol. MAIN OUTCOMES AND MEASURES In-hospital mortality. RESULTS The mean (SD) Injury Severity Score was 28.4 (16.2), the mean (SD) base deficit was -9.8 (6.3), and median international normalized ratio was 1.3 (interquartile range, 1.2-1.6); the mortality rate was 40.8%. Patients received a median of 6.1 L of crystalloid, 13 units of RBCs, 10 units of FFP, and 1 unit of platelets over 24 hours, with a mean RBC:FFP ratio of 1.58:1. The mean 24-hour crystalloid infusion volume and number of the total blood product units given in the first 24 hours decreased significantly over the study period (P < .05). The RBC:FFP ratio decreased from a peak of 1.84:1 in 2007 to 1.55:1 in 2011 (P = .20). Injury severity and mortality remained stable over the study period. When adjusted for age and injury characteristics using Cox regression, each decrease of 0.1 achieved in the massive transfusion protocols RBC:FFP ratio was associated with a 5.6% reduction in mortality (P = .005). CONCLUSIONS AND RELEVANCE There has been a shift toward a reduced crystalloid volume and the recreation of whole blood from component products in resuscitation. These changes are associated with markedly improved outcomes and a new paradigm in the resuscitation of severely injured patients.

Fibrinogen and platelet contributions to clot formation: implications for trauma resuscitation and thromboprophylaxis.

BACKGROUND Thromboelastography (TEG) is used to diagnose perturbations in clot formation and lysis that are characteristic of acute traumatic coagulopathy. With novel functional fibrinogen (FF) TEG, fibrin- and platelet-based contributions to clot formation can be elucidated to tailor resuscitation and thromboprophylaxis. We sought to describe the longitudinal contributions of fibrinogen and platelets to clot strength after injury, hypothesizing that low levels of FF and a low contribution of fibrinogen to clot strength on admission would be associated with coagulopathy, increased transfusion requirements, and worse outcomes. METHODS A total of 603 longitudinal plasma samples were prospectively collected from 251 critically injured patients at a single Level 1 trauma center from 0 hour to 120 hours. TEG maximal amplitude (MA), FF MA, FF levels, von Clauss fibrinogen, and standard coagulation measures were performed in parallel. Percentage contributions of FF (%MAFF) and platelets (%MAplatelets) were calculated as each MA divided by overall kaolin TEG MA. RESULTS Coagulopathic patients (international normalized ratio ≥ 1.3) had significantly lower admission %MAFF than noncoagulopathic patients (24.7% vs. 31.2%, p < 0.05). Patients requiring plasma transfusion had a significantly lower admission %MAFF (26.6% vs. 30.6%, p < 0.05). Higher admission %MAFF was predictive of reduced mortality (hazard ratio, 0.815, p < 0.001). %MAplatelets was higher than %MAFF at all time points, decreased over time, and stabilized at 72 hours (69.4% at 0 hour, 56.2% at 72 hours). In contrast, %MAFF increased over time and stabilized at 72 hours (30.6% at 0 hour, 43.8% at 72 hours). CONCLUSION FF TEG affords differentiation of fibrin- versus platelet-based clot dynamics. Coagulopathy and plasma transfusion were associated with a lower %MAFF. Despite this importance of fibrinogen, platelets had a greater contribution to clot strength at all time points after injury. This suggests that attention to these relative contributions should guide resuscitation and thromboprophylaxis and that antiplatelet therapy may be of underrecognized importance to thromboprophylaxis after trauma. LEVEL OF EVIDENCE Prognostic study, level III.

The whole is greater than the sum of its parts: Hemostatic profiles of whole blood variants

BACKGROUND Mounting evidence highlighting the benefits of hemostatic resuscitation has led to a renewed interest in whole blood (WB) and reconstituted WB (RWB). However, few data exist to characterize the clotting profiles of these variants. This study characterizes banked WB variants and RWB in standard 1:1:1 and 2:1:1 transfusion ratios of packed red blood cells, fresh frozen plasma, and platelets (PLTs). We hypothesized that the global hemostatic profile of 1:1:1 RWB is superior to 2:1:1 RWB and that PLT-modified WB (MWB) is superior to 1:1:1 RWB. METHODS Twenty-three units of packed red blood cells, fresh frozen plasma, and PLTs were obtained from the regional blood collection center and mixed to create 23 1:1:1 and 23 2:1:1 RWB units. Freshly donated WB units were obtained and used to create 11 of each nonmodified WB (NMWB) (room temperature and cooled) and MWB (room temperature and cooled) variants. International normalized ratio (INR)/partial thromboplastin time (PTT), complete blood cell count, functional studies, and an extensive panel of procoagulant and anticoagulant factor assays were performed on all products. RESULTS The 1:1:1 RWB had significantly lower INR and PTT (1.31 vs. 1.55, p = 0.0029; 42 seconds vs. 50 seconds, p = 0.0008) and higher activity of factors II, V, VII, VIII, IX, and X; antithrombin III, as well as protein C and higher fibrinogen levels than did 2:1:1 RWB (factor IX, 86% vs. 70%, p = 0.0313; fibrinogen, 242 mg/dL vs. 202 mg/dL, p = 0.0385). There were no differences in INR/PTT or factor activity between MWB and NMWB. However, MWB had greater maximum clot firmness (MCF) by rotational thromboelastometry tissue factor–activated extrinsic clotting cascade measures than did NMWB (MCF, 61 mm vs. 50 mm, p = 0.0031). MWB also had greater MCF by rotational thromboelastometry tissue factor–activated extrinsic clotting cascade measures than did 1:1:1 RWB (MCF, 61 mm vs. 45 mm, p = 0.0005). CONCLUSION Although 1:1:1 RWB had a superior clotting profile relative to 2:1:1 RWB, MWB exhibited even better global hemostasis than did 1:1:1 RWB. Characterization of factor-level and functional clotting differences between WB variants is imperative for understanding the clinical benefits of hemostatic resuscitation.

Blunt cerebrovascular injuries in the child.

BACKGROUND Although blunt cerebrovascular injuries (BCVIs) are a well-recognized sequela of trauma in adults, there have been few reports in children. The investigators questioned whether adult screening protocols are appropriate in the pediatric population. The purpose of this study was to describe the incidence, injury patterns, and stroke rates of pediatric patients sustaining BCVIs. METHODS Pediatric patients (aged ≤ 18 years) diagnosed with BCVIs at a regional level I trauma center and a pediatric level I trauma center since 1996 were reviewed. RESULTS Forty-five patients sustained BCVIs (60% male; mean age, 13 ± .7 years; mean Injury Severity Score, 23 ± 2). Three patients exsanguinated, and 10 presented with stroke; neurologic changes occurred 17 ± 6 hours after injury (range, 1-72 hours). Screening indications were present in 30%. Thirty-two asymptomatic patients were diagnosed. All but 1 received antithrombotic agents; 1 patient had neurologic deterioration despite heparinization. Comparing asymptomatic patients with those with stroke, there was a significant difference in age (15 vs 11 years). CONCLUSIONS More than two-thirds of patients presenting with stroke did not have screening indications according to adult protocols. With the availability of noninvasive diagnostic imaging such as computed tomographic angiography, broader screening guidelines for children should be instituted.

Future of acute care surgery: a perspective from the next generation.

Background: Access to emergent surgical care has been identified as a crisis in the United States. To address this challenge, the American Association for Surgery of Trauma has developed a fellowship in acute care surgery (ACS) to reestablish broad-based surgical capabilities. But the viability of this new discipline will rest on the interests of the next generation of surgeons. The objective of this study was to determine key factors influencing the choice of surgical specialties among medical students with a focus on their interest in trauma/ACS (T/ACS). Methods: An online questionnaire was distributed to students at four medical schools affiliated with Level I trauma centers, one of which also has an ACS fellowship. The survey was sent to medical students at all levels (first to fourth year). Students with an interest in surgery as a career were asked to complete the survey and rank factors and experiences influencing career selection on a scale of 1 (no influence) to 10 (critical). Students were also asked to select their top five surgical specialties. Results: Three hundred thirty-seven students interested in surgery responded. Mean age was 26 years ± 0.2 years (range, 20–37 years), 58% were men, and 86% were single. Respondents were distributed evenly over medical schools and medical school years. The three most popular career choices were orthopedics (16%), T/ACS (12%), and pediatric surgery (8%). As students progressed through medical school, lifestyle factors such as predictable hours and family time became more important in influencing their career choice. Overall, 115 students (34%) selected emergent surgery (T/ACS) as one of their top three career choices. Factors that were ranked significantly higher by students interested in T/ACS were related to professional satisfaction. These students also placed less emphasis on lifestyle factors when choosing a surgical career. Conclusions: Our results indicate that there is a reassuring interest to address the growing demand for emergency surgery among current medical students exposed to a broad range of T/ACS patients in Level I trauma centers. The T/ACS model is in accordance with the drives of these students looking for a diverse and challenging profession. Academic societies should make further efforts to encourage medical students to pursue T/ACS.

Differences in degree, differences in kind: characterizing lung injury in trauma

BACKGROUND Acute lung injury following trauma remains a significant source of morbidity and mortality. Although multiple trauma studies have used hypoxemia without radiographic adjudication as a surrogate for identifying adult respiratory distress syndrome (ARDS) cases, the differences between patients with hypoxemia alone and those with radiographically confirmed ARDS are not well described in the literature. We hypothesized that nonhypoxemic, hypoxemic, and ARDS patients represent distinct groups with unique characteristics and predictors. METHODS Laboratory, demographic, clinical, and outcomes data were prospectively collected from 621 intubated, critically injured patients at an urban Level 1 trauma center from 2005 to 2013. Hypoxemia was defined as PaO2/FIO2 ratio of 300 or lower. ARDS was adjudicated using Berlin criteria, with blinded two-physician consensus review of chest radiographs. Group comparisons were performed by hypoxemia and ARDS status. Logistic regression analyses were performed to separately assess predictors of hypoxemia and ARDS. RESULTS Of the 621 intubated patients, 64% developed hypoxemia; 46% of these hypoxemic patients developed ARDS by chest radiograph. Across the three groups (no hypoxemia, hypoxemia, ARDS), there were no significant differences in age, sex, or comorbidities. However, there was an increase in severity of shock, injury, and chest injury by group, with corresponding trends in transfusion requirements and volume of early fluid administration. Outcomes followed a similar stepwise pattern, with pneumonia, multiorgan failure, length of intensive care unit stay, number of ventilator days, and overall mortality highest in ARDS patients. In multiple logistic regression, early plasma transfusion, delayed crystalloid administration, body mass index, and head and chest injury were independent predictors of hypoxemia, while head and chest injury, early crystalloid infusion, and delayed platelet transfusion were independent predictors of ARDS. CONCLUSION Hypoxemia and ARDS exist on a spectrum of respiratory dysfunction following trauma, with increasing injury severity profiles and resuscitation requirements. However, they also represent distinct clinical states with unique predictors, which require directed research approaches and targeted therapeutic strategies. LEVEL OF EVIDENCE Prognostic and epidemiologic study, level III.

Blunt trauma induced splenic blushes are not created equal

BackgroundCurrently, evidence of contrast extravasation on computed tomography (CT) scan is regarded as an indication for intervention in splenic injuries. In our experience, patients transferred from other institutions for angioembolization have often resolved the blush upon repeat imaging at our hospital. We hypothesized that not all splenic blushes require intervention.MethodsDuring a 10-year period, we reviewed all patients transferred with blunt splenic injuries and contrast extravasation on initial postinjury CT scan.ResultsDuring the study period, 241 patients were referred for splenic injuries, of whom 16 had a contrast blush on initial CT imaging (88% men, mean age 35 ± 5, mean ISS 26 ± 3). Eight (50%) patients were managed without angioembolization or operation. Comparing patients with and without intervention, there was a significant difference in admission heart rate (106 ± 9 vs 83 ± 6) and decline in hematocrit following transfer (5.3 ± 2.0 vs 1.0 ± 0.3), but not in injury grade (3.9 ± 0.2 vs 3.5 ± 0.3), systolic blood pressure (125 ± 10 vs 115 ± 6), or age (38.5 ± 8.2 vs 30.9 ± 4.7). Of the 8 observed patients, 3 underwent repeat imaging immediately upon arrival with resolution of the blush. In the intervention group, 4 patients had ongoing extravasation on repeat imaging, 2 patients underwent empiric embolization, and 2 patients underwent splenectomy for physiologic indications.ConclusionsFor blunt splenic trauma, evidence of contrast extravasation on initial CT imaging is not an absolute indication for intervention. A period of observation with repeat imaging could avoid costly, invasive interventions and their associated sequelae.

The acute respiratory distress syndrome following isolated severe traumatic brain injury.

BACKGROUND Acute respiratory distress syndrome (ARDS) is common after traumatic brain injury (TBI) and is associated with worse neurologic outcomes and longer hospitalization. However, the incidence and associated causes of ARDS in isolated TBI have not been well studied. METHODS We performed a subgroup analysis of 210 consecutive patients with isolated severe TBI enrolled in a prospective observational cohort at a Level 1 trauma center between 2005 and 2014. Subjects required endotracheal intubation and had isolated severe TBI defined by a head Abbreviated Injury Scale (AIS) score of 3 or greater and AIS score lower than 3 in all other categories. ARDS within the first 8 days of admission was rigorously adjudicated using Berlin criteria. Regression analyses were used to test the association between predictors of interest and ARDS. RESULTS The incidence of ARDS in the first 8 days after severe isolated TBI was 30%. Patients who developed ARDS were administered more crystalloids (4.3 L vs. 3.5 L, p = 0.005) and blood products in the first 12 hours of admission. Patients with ARDS had significantly worse clinical outcomes measured at 28 days, including longer median intensive care unit and hospital stays (4 days vs. 13 days, p < 0.001, and 7.5 days vs. 14.5 days, p < 0.001, respectively). In unadjusted logistic regression analyses, the odds of developing ARDS were significantly associated with head AIS score (odds ratio [OR], 1.8; p = 0.018), male sex (OR, 2.9; p = 0.012), and early transfusion of platelets (OR, 2.8; p = 0.003). These associations were similar in a multivariate logistic regression model. CONCLUSION In the era of balanced hemostatic resuscitation practices, severity of head injury, male sex, early crystalloids, and early transfusion of platelets are associated with a higher risk of ARDS after severe isolated TBI. Early transfusion of platelets after severe TBI may be a modifiable risk factor for ARDS, and these findings invite further investigation into causal mechanisms driving this observed association. LEVEL OF EVIDENCE Prognostic/epidemiologic study, level III.

Obesity and clotting: Body mass index independently contributes to hypercoagulability after injury.

BACKGROUND Although obese patients have high thrombosis rates following injury, the role of obesity in coagulation after trauma remains unknown. We hypothesized that body mass index (BMI) is independently associated with increased measures of hypercoagulability longitudinally after injury. METHODS Data were prospectively collected for 377 consecutive highest-level trauma activation patients with a BMI of 18.5 kg/m2 or greater. Standard coagulation measures, citrated kaolin and functional fibrinogen thromboelastography, as well as clotting factors were measured at 0 hour to 120 hours. BMI categories were defined as normal weight (18.5–24.99 kg/m2), overweight (25–29.99 kg/m2), and obese (≥30 kg/m2). RESULTS The 377 patients were mostly male (81%) and had blunt injury (61%), with a median BMI of 25.8 kg/m2. Of the patients, 42% were normal weight (median BMI, 22.5 kg/m2). There were no differences in age, sex, Injury Severity Score (ISS), or base deficit between groups. There were no differences in admission international normalized ratio/partial thromboplastin time or factors II, V, VII, VIII, and X; antithrombin III; or protein C. However, obese patients had higher admission platelet counts (303 × 109/L vs. 269 × 109/L, p = 0.004), lower D-dimer (1.88 &mgr;g/mL vs. 4.00 &mgr;g/mL, p = 0.004), and a trend toward higher factor IX (134% vs. 119% activity, p = 0.042) compared with normal weight patients. Measured by thromboelastography, clot strength (maximum amplitude) and functional fibrinogen level (FLEV) were also higher on admission for obese patients (maximum amplitude, 65.7 mm vs. 63.4 mm, p = 0.016; FLEV, 407 mg/dL vs. 351 mg/dL, p = 0.008). In multiple linear regression, the relationship of BMI to clot strength, FLEV, and factor IX persisted through 24 hours. Similarly, the relationship of BMI and platelet count persisted through 120 hours (all p < 0.05). In multiple logistic regression, for every 5-kg/m2 increase in BMI, there was an 85% increase in odds of thromboembolic complication (odds ratio, 1.85; 95% confidence interval, 1.13–3.08; p = 0.017). CONCLUSION Obese trauma patients are hypercoagulable compared with their similarly injured normal-weight counterparts, which persists longitudinally after injury. The significance of this hypercoagulability requires elucidation for guidance of anticoagulation in this at-risk group. LEVEL OF EVIDENCE Prognostic study, level III.