Impact of Enteral Albuterol on Bradycardic Events After Acute Cervical Spinal Cord Injury.

BACKGROUND: Acute cervical spinal cord injury (ACSCI) is commonly complicated by spinal shock, resulting in hemodynamic instability characterized by bradycardia and hypotension that can have fatal consequences. Current guidelines recommend the use of intravenous beta and dopamine agonists, such as norepinephrine and dopamine, respectively. We sought to determine whether enteral albuterol would be a safe and feasible treatment for bradycardia without an increase in the occurrence of known side effects of albuterol in patients with ACSCI. METHODS: A retrospective review of patients with ACSCI admitted to an intensive care unit at a level I trauma center and treated with enteral albuterol was conducted. Patients were excluded for the following reasons: pure beta blocker use prior to injury, concurrent use of pacemaker, age of less than 18 years, or age more than 75 years. As part of the standard of care, all patients underwent mean arterial pressure (MAP) augmentation to reach a goal of greater than 85 mm Hg during the first 7 days post injury. All eligible patient charts were reviewed for demographic characteristics, daily minimum and maximum heart rate and MAP, and concomitant vasoactive medication use. Bradycardia and tachycardia were defined as heart rate less than 60 beats per minute (bpm) and greater than 100 bpm, respectively. Factors found to be associated with bradycardia on univariate analysis were entered into a multivariable generalized estimating equation analysis to determine factors independently associated with bradycardia during the study period. RESULTS: There were 58 patients with cervical ASCI (age 45 ± 18 years, 76% men) admitted between January 1, 2016, and December 31, 2017, that met the study criteria. The mean time to initiation of albuterol was 1.5 ± 1.7 days post injury, with a duration of 9.3 ± 4.5 days and a mean daily dosage of 7.8 ± 4.5 mg. Bradycardia was observed in 136 of 766 patient days (17%). There were a few episodes of hyperglycemia (1%) and tachycardia (3%), but no episodes of hypokalemia. In a multivariable analysis, female sex (P = 0.006) and American Spinal Cord Injury Association grade A, B, or C (P < 0.001) were associated with a higher risk of developing bradycardia, whereas dosage of albuterol (P = 0.009) and norepinephrine use (P = 0.008) were associated with a lower risk of developing bradycardia. CONCLUSIONS: Albuterol administration in ASCI is a safe and feasible treatment for bradycardia, given that no significant side effects, such as hyperglycemia, hypokalemia, or tachycardia, were observed. The administration of enteral albuterol was well tolerated and, in a dose-dependent manner, associated with a lower occurrence of bradycardia. Further prospective trials for the use of enteral albuterol after SCI are warranted.

Measured vs Predicted Energy Expenditure in Mechanically Ventilated Adults With Acute, Traumatic Spinal Cord Injuries.

BACKGROUND: Research regarding the impact of acute spinal cord injury (aSCI) on energy expenditure is limited. Patients with aSCI are prone to complications of both over- and under-feeding, making appropriate nutrition support pivotal to patient care. The purpose of this study was to describe energy expenditure and assess the performance of predictive equations in mechanically ventilated adults with aSCI. METHODS: Adult patients admitted to a single trauma center from March 2017 through June 2018 with aSCI and a documented indirect calorimetry (IC) within 6 weeks of injury were included for analysis. Predictive equations evaluated included Penn State 2003b (PS 2003b), the derived Weir equation, 25 kcal/kg and 30 kcal/kg. Sub-set analysis was performed for patients with and without obesity, isolated aSCI, and concomitant traumatic injuries. RESULTS: On hundres fifteen IC studies in 51 patients were included for analysis. Median energy expenditure was 1747 kcal/day (interquartile range [IQR], 1492-2099 kcal/day), or 22.7 kcal/kg (IQR, 19.3-25.9 kcal/kg). When stratified by hospital day, energy expenditure ranged from 20 to 25 kcal/kg. PS 2003b and the derived Weir equation had similar correlation coefficients (r = 0.81 and 0.82, respectively). The 25 and 30 kcal/kg performed unacceptably (r = 0.61). PS 2003b predicted within 10% of measured energy expenditure most frequently. All equations were biased towards overfeeding, except for PS 2003b in the obese subset. CONCLUSION: In the absence of IC, PS 2003b or the derived Weir equation may be acceptable predictive equations in this population. However, bedside clinicians should monitor carefully for signs and symptoms of overfeeding.

Prognostication of Mortality and Long-Term Functional Outcomes Following Traumatic Brain Injury: Can We Do Better?

Accurate prognostication of outcomes following traumatic brain injury (TBI) affects not only the aggressiveness of intervention and therapeutic decision-making but also clinicians' ability to provide reliable expectations. To investigate the relative ability of clinicians to accurately predict a patient's outcomes, compared with point-of-care prognostic models, we surveyed clinical providers of 86 patients with moderate-severe TBI at admission, Day 3, and Day 7 post-injury for a patient's predicted mortality and functional outcome at 6 months. The predicted mortality and functional outcomes were compared with actual occurrence of 14-day mortality and functional outcomes at six months. A prognostic score was then calculated utilizing the Corticoid Randomization After Significant Head Injury (CRASH) and International Mission on Prognosis and Analysis of Clinical Trials (IMPACT) models and categorized as high, intermediate, and low likelihood of mortality or poor functional outcome, and compared with clinical predictions. Overall, clinicians of varying backgrounds showed an accurate prediction of survival (87.2-97.4%) but struggled in prognosticating poor functional outcomes (24.3-36.6%). These values did not statistically improve over 7 days. Stratified CRASH (87.2%) and IMPACT (84.9%) accuracy rates were statistically better than clinical judgment alone in predicting functional outcomes (p < 0.0001). Prognostic models calculated at admission showed to be potentially useful, in conjunction with clinical judgment, in accurately predicting both survival and 6-month functional outcomes.

Outcomes in patients with gunshot wounds to the brain.

INTRODUCTION: Gunshot wounds to the brain (GSWB) confer high lethality and uncertain recovery. It is unclear which patients benefit from aggressive resuscitation, and furthermore whether patients with GSWB undergoing cardiopulmonary resuscitation (CPR) have potential for survival or organ donation. Therefore, we sought to determine the rates of survival and organ donation, as well as identify factors associated with both outcomes in patients with GSWB undergoing CPR. METHODS: We performed a retrospective, multicenter study at 25 US trauma centers including dates between June 1, 2011 and December 31, 2017. Patients were included if they suffered isolated GSWB and required CPR at a referring hospital, in the field, or in the trauma resuscitation room. Patients were excluded for significant torso or extremity injuries, or if pregnant. Binomial regression models were used to determine predictors of survival/organ donation. RESULTS: 825 patients met study criteria; the majority were male (87.6%) with a mean age of 36.5 years. Most (67%) underwent CPR in the field and 2.1% (n=17) survived to discharge. Of the non-survivors, 17.5% (n=141) were considered eligible donors, with a donation rate of 58.9% (n=83) in this group. Regression models found several predictors of survival. Hormone replacement was predictive of both survival and organ donation. CONCLUSION: We found that GSWB requiring CPR during trauma resuscitation was associated with a 2.1% survival rate and overall organ donation rate of 10.3%. Several factors appear to be favorably associated with survival, although predictions are uncertain due to the low number of survivors in this patient population. Hormone replacement was predictive of both survival and organ donation. These results are a starting point for determining appropriate treatment algorithms for this devastating clinical condition. LEVEL OF EVIDENCE: Level II.

Validation of predictive equations to assess energy expenditure in acute spinal cord injury.

BACKGROUND: Acute spinal cord injury (SCI) is devastating with morbidities compounded by inadequate nutrition. The American Society for Parenteral and Enteral Nutrition recommends indirect calorimetry (IC) to evaluate energy needs in SCI because no predictive energy equations have been validated. We sought to determine the accuracy of predictive equations to predict measured energy expenditure (MEE). METHODS: A retrospective review was performed over 2 years. Patients 18 years or older with cervical SCI who received IC were included. Height, weight, maximum temperature and minute ventilation on day of IC, plus MEE and VCO2 from IC were obtained. Predicted energy expenditure (PEE) was calculated using Harris-Benedict (HB), Penn State (PS), Mifflin St. Jeor (MSJ), Weir, Ireton-Jones (IJ), and 25 kcal/kg formulas. MEE was then compared to the PEE of each method. RESULTS: Thirty-nine IC studies were completed for 20 patients. Weir had the strongest correlation to MEE (r = 0.98), followed by PS (r = 0.82). Correlations were similar among HB (r = 0.78), MSJ (r = 0.75), and IJ (r = 0.73), and weakest with 24 kcal/kg (r = 0.55). All had a p value <0.001. Deming regression confirmed strong correlations between Weir and PS to MEE, with coefficients of 1.03 and 1.515 (p < 0.001), respectively. Other formulas had comparatively higher coefficients and standard errors. Bland-Altman analysis confirmed Weir had the narrowest range of difference, with a mean difference of 25.5 kcal/day, followed by PS (-336.1 kcal/day). CONCLUSIONS: Weir is the best predictive energy equation, with all statistical tests demonstrating a strong correlation between MEE and Weir. The second best predictive equation is the Penn State formula, which predicts actual MEE measured by IC with high accuracy. LEVEL OF EVIDENCE: Diagnostic study, level III.

Intramedullary Lesion Length on Postoperative Magnetic Resonance Imaging is a Strong Predictor of ASIA Impairment Scale Grade Conversion Following Decompressive Surgery in Cervical Spinal Cord Injury.

BACKGROUND: Evidence indicates that, over time, patients with spinal cord injury (SCI) improve neurologically in various degrees. We sought to further investigate indicators of grade conversion in cervical SCI. OBJECTIVE: To detect predictors of ASIA impairment scale (AIS) grade conversion in SCI following surgical decompression. METHODS: In a retrospective study, demographics, clinical, imaging, and surgical data from 100 consecutive patients were assessed for predictors of AIS grade conversion. RESULTS: American Spinal Injury Association motor score was 17.1. AIS grade was A in 52%, B in 29%, and C in 19% of patients. Surgical decompression took place on an average of 17.6 h following trauma (≤12 h in 51 and >12 h in 49). Complete decompression was verified by magnetic resonance imaging (MRI) in 73 patients. Intramedullary lesion length (IMLL) on postoperative MRI measured 72.8 mm, and hemorrhage at the injury epicenter was noted in 71 patients. Grade conversion took place in 26.9% of AIS grade A patients, 65.5% of AIS grade B, and 78.9% of AIS grade C. AIS grade conversion had statistical relationship with injury severity score, admission AIS grade, extent of decompression, presence of intramedullary hemorrhage, American Spinal Injury Association motor score, and IMLL. A stepwise multiple logistic regression analysis indicated IMLL was the sole and strongest indicator of AIS grade conversion (odds ratio 0.950, 95% CI 0.931-0.969). For 1- and 10-mm increases in IMLL, the model indicates 4% and 40% decreases, respectively, in the odds of AIS grade conversion. CONCLUSION: Compared with other surrogates, IMLL remained as the only predictor of AIS grade conversion.

Predictors of intramedullary lesion expansion rate on MR images of patients with subaxial spinal cord injury.

OBJECT Studies of preclinical spinal cord injury (SCI) in rodents indicate that expansion of intramedullary lesions (IMLs) seen on MR images may be amenable to neuroprotection. In patients with subaxial SCI and motor-complete American Spinal Injury Association (ASIA) Impairment Scale (AIS) Grade A or B, IML expansion has been shown to be approximately 900 µm/hour. In this study, the authors investigated IML expansion in a cohort of patients with subaxial SCI and AIS Grade A, B, C, or D. METHODS Seventy-eight patients who had at least 2 MRI scans within 6 days of SCI were enrolled. Data were analyzed by regression analysis. RESULTS In this cohort, the mean age was 45.3 years (SD 18.3 years), 73 patients were injured in a motor vehicle crash, from a fall, or in sport activities, and 77% of them were men. The mean Injury Severity Score (ISS) was 26.7 (SD 16.7), and the AIS grade was A in 23 patients, B in 7, C in 7, and D in 41. The mechanism of injury was distraction in 26 patients, compression in 22, disc/osteophyte complex in 29, and Chance fracture in 1. The mean time between injury onset and the first MRI scan (Interval 1) was 10 hours (SD 8.7 hours), and the mean time to the second MRI scan (Interval 2) was 60 hours (SD 29.6 hours). The mean IML lengths of the first and second MR images were 38.8 mm (SD 20.4 mm) and 51 mm (SD 36.5 mm), respectively. The mean time from the first to the second MRI scan (Interval 3) was 49.9 hours (SD 28.4 hours), and the difference in IML lengths was 12.6 mm (SD 20.7 mm), reflecting an expansion rate of 366 µm/ hour (SD 710 µm/hour). IML expansion in patients with AIS Grades A and B was 918 µm/hour (SD 828 µm/hour), and for those with AIS Grades C and D, it was 21 µm/hour (SD 304 µm/hour). Univariate analysis indicated that AIS Grade A or B versus Grades C or D (p < 0.0001), traction (p= 0.0005), injury morphology (p < 0.005), the surgical approach (p= 0.009), vertebral artery injury (p= 0.02), age (p < 0.05), ISS (p < 0.05), ASIA motor score (p < 0.05), and time to decompression (p < 0.05) were all predictors of lesion expansion. In multiple regression analysis, however, the sole determinant of IML expansion was AIS grade (p < 0.005). CONCLUSIONS After traumatic subaxial cervical spine or spinal cord injury, patients with motor-complete injury (AIS Grade A or B) had a significantly higher rate of IML expansion than those with motor-incomplete injury (AIS Grade C or D).

Intramedullary lesion expansion on magnetic resonance imaging in patients with motor complete cervical spinal cord injury.

OBJECT: The authors performed a study to determine if lesion expansion occurs in humans during the early hours after spinal cord injury (SCI), as has been established in rodent models of SCI, and to identify factors that might predict lesion expansion. METHODS: The authors studied 42 patients with acute cervical SCI and admission American Spinal Injury Association Impairment Scale Grades A (35 patients) and B (7 patients) in whom 2 consecutive MRI scans were obtained 3-134 hours after trauma. They recorded demographic data, clinical information, Injury Severity Score (ISS), admission MRI-documented spinal canal and cord characteristics, and management strategies. RESULTS: The characteristics of the cohort were as follows: male/female ratio 37:5; mean age, 34.6 years; and cause of injury, motor vehicle collision, falls, and sport injuries in 40 of 42 cases. The first MRI study was performed 6.8 ±2.7 hours (mean ± SD) after injury, and the second was performed 54.5 ± 32.3 hours after injury. The rostrocaudal intramedullary length of the lesion on the first MRI scan was 59.2 ± 16.1 mm, whereas its length on the second was 88.5 ± 31.9 mm. The principal factors associated with lesion length on the first MRI study were the time between injury and imaging (p = 0.05) and the time to decompression (p = 0.03). The lesion's rate of rostrocaudal intramedullary expansion in the interval between the first and second MRI was 0.9 ± 0.8 mm/hour. The principal factors associated with the rate of expansion were the maximum spinal cord compression (p = 0.03) and the mechanism of injury (p = 0.05). CONCLUSIONS: Spinal cord injury in humans is characterized by lesion expansion during the hours following trauma. Lesion expansion has a positive relationship with spinal cord compression and may be mitigated by early surgical decompression. Lesion expansion may be a novel surrogate measure by which to assess therapeutic effects in surgical or drug trials.