Alberto Aiolfi, Desmond Khor, Jayun Cho, Elizabeth Benjamin, Kenji Inaba and Demetrios Demetriades
Intracranial pressure (ICP) monitoring has become the standard of care in the management of severe head trauma. Intraventricular devices (IVDs) and intraparenchymal devices (IPDs) are the 2 most commonly used techniques for ICP monitoring. Despite the widespread use of these devices, very few studies have investigated the effect of device type on outcomes. The purpose of the present study was to compare outcomes between 2 types of ICP monitoring devices in patients with isolated severe blunt head trauma.
This retrospective observational study was based on the American College of Surgeons Trauma Quality Improvement Program database, which was searched for all patients with isolated severe blunt head injury who had an ICP monitor placed in the 2-year period from 2013 to 2014. Extracted variables included demographics, comorbidities, mechanisms of injury, head injury specifics (epidural, subdural, subarachnoid, intracranial hemorrhage, and diffuse axonal injury), Abbreviated Injury Scale (AIS) score for each body area, Injury Severity Score (ISS), vital signs in the emergency department, and craniectomy. Outcomes included 30-day mortality, complications, number of ventilation days, intensive care unit and hospital lengths of stay, and functional independence.
During the study period, 105,721 patients had isolated severe traumatic brain injury (head AIS score ≥ 3). Overall, an ICP monitoring device was placed in 2562 patients (2.4%): 1358 (53%) had an IVD and 1204 (47%) had an IPD. The severity of the head AIS score did not affect the type of ICP monitoring selected. There was no difference in the median ISS; ISS > 15; head AIS Score 3, 4, or 5; or the need for craniectomy between the 2 device groups. Unadjusted 30-day mortality was significantly higher in the group with IVDs (29% vs 25.5%, p = 0.046); however, stepwise logistic regression analysis showed that the type of ICP monitoring was not an independent risk factor for death, complications, or functional outcome at discharge.
This study demonstrated that compliance with the Brain Trauma Foundation guidelines for ICP monitoring is poor. In isolated severe blunt head injuries, the type of ICP monitoring device does not have any effect on survival, systemic complications, or functional outcome.
Jennifer T. Cone, Elizabeth R. Benjamin, Daniel B. Alfson and Demetrios Demetriades
Obesity has been widely reported to confer significant morbidity and mortality in both medical and surgical patients. However, contemporary data indicate that obesity may confer protection after both critical illness and certain types of major surgery. The authors hypothesized that this “obesity paradox” may apply to patients with isolated severe blunt traumatic brain injuries (TBIs).
The Trauma Quality Improvement Program (TQIP) database was queried for patients with isolated severe blunt TBI (head Abbreviated Injury Scale [AIS] score 3–5, all other body areas AIS < 3). Patient data were divided based on WHO classification levels for BMI: underweight (< 18.5 kg/m2), normal weight (18.5–24.9 kg/m2), overweight (25.0–29.9 kg/m2), obesity class 1 (30.0–34.9 kg/m2), obesity class 2 (35.0–39.9 kg/m2), and obesity class 3 (≥ 40.0 kg/m2). The role of BMI in patient outcomes was assessed using regression models.
In total, 103,280 patients were identified with isolated severe blunt TBI. Data were excluded for patients aged < 20 or > 89 years or with BMI < 10 or > 55 kg/m2 and for patients who were transferred from another treatment center or who showed no signs of life upon presentation, leaving data from 38,446 patients for analysis. Obesity was not found to confer a survival advantage on univariate analysis. On multivariate analysis, underweight patients as well as obesity class 1 and 3 patients had a higher rate of mortality (OR 1.86, 95% CI 1.48–2.34; OR 1.18, 95% CI 1.01–1.37; and OR 1.41, 95% CI 1.03–1.93, respectively). Increased obesity class was associated with an increased risk of respiratory complications (obesity class 1: OR 1.19, 95% CI 1.03–1.37; obesity class 2: OR 1.30, 95% CI 1.05–1.62; obesity class 3: OR 1.55, 95% CI 1.18–2.05) and thromboembolic complications (overweight: OR 1.43, 95% CI 1.16–1.76; obesity class 1: OR 1.45, 95% CI 1.11–1.88; obesity class 2: OR 1.55, 95% CI 1.05–2.29) despite a decreased risk of overall complications (obesity class 2: OR 0.82, 95% CI 0.73–0.92; obesity class 3: OR 0.83, 95% CI 0.72–0.97). Underweight patients had a significantly increased risk of overall complications (OR 1.39, 95% CI 1.24–1.57).
Although there was an obesity-associated decrease in overall complications, the study data did not demonstrate a paradoxical protective effect of obesity on mortality after isolated severe blunt TBI. Obese patients with isolated severe blunt TBI are at increased risk of respiratory and venous thromboembolic complications. However, underweight patients appear to be at highest risk after severe blunt TBI, with significantly increased risks of morbidity and mortality.
Peep Talving, Efstathios Karamanos, Pedro G. Teixeira, Dimitra Skiada, Lydia Lam, Howard Belzberg, Kenji Inaba and Demetrios Demetriades
The Brain Trauma Foundation (BTF) has established guidelines for intracranial pressure (ICP) monitoring in severe traumatic brain injury (TBI). This study assessed compliance with these guidelines and the effect on outcomes.
This is a prospective, observational study including patients with severe blunt TBI (Glasgow Coma Scale score ≤ 8, head Abbreviated Injury Scale score ≥ 3) between January 2010 and December 2011. Demographics, clinical characteristics, laboratory profile, head CT scans, injury severity indices, and interventions were collected. The study population was stratified into 2 study groups: ICP monitoring and no ICP monitoring. Primary outcomes included compliance with BTF guidelines, overall in-hospital mortality, and mortality due to brain herniation. Secondary outcomes were ICU and hospital lengths of stay. Multiple regression analyses were deployed to determine the effect of ICP monitoring on outcomes.
A total of 216 patients met the BTF guideline criteria for ICP monitoring. Compliance with BTF guidelines was 46.8% (101 patients). Patients with subarachnoid hemorrhage and those who underwent craniectomy/craniotomy were significantly more likely to undergo ICP monitoring. Hypotension, coagulopathy, and increasing age were negatively associated with the placement of ICP monitoring devices. The overall in-hospital mortality was significantly higher in patients who did not undergo ICP monitoring (53.9% vs 32.7%, adjusted p = 0.019). Similarly, mortality due to brain herniation was significantly higher for the group not undergoing ICP monitoring (21.7% vs 12.9%, adjusted p = 0.046). The ICU and hospital lengths of stay were significantly longer in patients subjected to ICP monitoring.
Compliance with BTF ICP monitoring guidelines in our study sample was 46.8%. Patients managed according to the BTF ICP guidelines experienced significantly improved survival.