Use of ECMO support in pediatric patients with severe thoracic trauma.

BACKGROUND: Extracorporeal membrane oxygenation (ECMO) has been used in the non-trauma setting for over 30 years. However, the use of ECMO in trauma remains a difficult question, as the risk of bleeding must be weighed against the benefits of cardiopulmonary support. METHODS: Retrospective review of children who sustained severe thoracic trauma (chest abbreviated injury score ≥3) and required ECMO support between 2009 and 2016. RESULTS: Of the 425 children who experienced severe thoracic trauma, 6 (1.4%) underwent ECMO support: 67% male, median age 4.8 years, median ISS 36, median GCS 3, and overall survival 83%. The median hospital day of ECMO initiation was 2 with a median ECMO duration of 7 days. All cannulations occurred through the right neck regardless of the size of the child. Five initially had veno-venous support with 1 requiring conversion to veno-arterial (VA) support. Both children on VA support suffered devastating cerebrovascular accidents, one of which ultimately led to withdrawal of care and death. Complications in the cohort included: paraplegia (1), neurocognitive defects/dysphonia (1), infected neck hematoma (1), deep femoral venous thrombosis (1), bilateral lower extremity spasticity (1). CONCLUSION: This small cohort supports the use of ECMO in children with severe thoracic injuries as a potentially lifesaving intervention, however, not without significant complication. LEVEL OF EVIDENCE: IV.

Weight-Based Dosing for Once-Daily Enoxaparin Cannot Provide Adequate Anticoagulation for Venous Thromboembolism Prophylaxis.

BACKGROUND: Surgeons commonly provide enoxaparin prophylaxis to high-risk patients to decrease venous thromboembolism risk. The authors' prior work demonstrated that most patients receive inadequate venous thromboembolism prophylaxis, based on anti-factor Xa level, when enoxaparin 40 mg/day is provided and that peak anti-factor Xa level correlates with weight. This study models a weight-based strategy for daily enoxaparin prophylaxis and its impact on anti-factor Xa levels. METHODS: The authors enrolled plastic surgery patients who received enoxaparin 40 mg/day and had anti-factor Xa levels drawn. The enoxaparin dose of 40 mg was converted to a milligram-per-kilogram dose for each patient. Stratified analysis examined the milligram-per-kilogram dose that produced low, in-range, and high anti-factor Xa levels to identify the appropriate milligram-per-kilogram dose to optimize venous thromboembolism prevention and bleeding events. RESULTS: Among 94 patients, weight-based dosing ranged from 0.28 to 0.94 mg/kg once daily. For peak and trough anti-factor Xa levels, there was nearly complete overlap for milligram-per-kilogram dosing that produced low versus in-range anti-factor Xa levels. For peak anti-factor Xa, there was nearly complete overlap for milligram-per-kilogram dosing that produced in-range versus high anti-factor Xa levels. Mean milligram-per-kilogram dose was not significantly different between patients who did or did not have postoperative venous thromboembolism (0.41 mg/kg versus 0.52 mg/kg; p = 0.085) or clinically relevant bleeding (0.48 mg/kg versus 0.51 mg/kg; p = 0.73). CONCLUSIONS: Alterations in enoxaparin dose magnitude based on patient weight cannot allow a high proportion of patients to achieve appropriate anti-factor Xa levels when once-daily enoxaparin prophylaxis is provided. Future research should examine the impact of increased enoxaparin dose frequency on anti-factor Xa levels, venous thromboembolism events, and bleeding. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

The utility of a "trauma 1 OP" activation at a level 1 pediatric trauma center.

PURPOSE: To expedite flow of injured children suspected to require operative intervention, a "trauma 1 OP" (T1OP) activation classification was created. The purpose of this study was to review this strategy at a level 1 pediatric trauma center. METHODS: A retrospective review of T1OP activations between 2003 and 2015 was performed. Children suspected of requiring neurosurgical intervention were classified as trauma 1 OP neuro (T1OP(N)). Comparisons were made to trauma 1 (T1) patients who required emergent operative intervention, excluding orthopedic injuries. RESULTS: Overall, 461 T1OP activations occurred (72% T1OP(N)) compared to 129 T1 activations requiring emergent surgery. Demographics were not significantly different between groups, although T1OP patients were slightly younger and more often experienced falls or were victims of abuse. Compared to T1 activations, T1OP activations had a significantly higher mortality rate (21% vs. 7%, p<0.001). Repeat head imaging was more common in the T1OP(N) group compared to imaged children in the T1 group (20% vs. 37%, p=0.05). T1OP(N) patients more often went directly to the OR (45% vs. 33%, p=0.02) and did so in a significantly faster period of time (32min vs. 53min, p<0.001). CONCLUSIONS: Use of the T1OP activations appropriately triaged surgical patients, resulting in significantly faster transport times to the OR. LEVEL OF EVIDENCE: II, prognosis study.

Prior methamphetamine self-administration attenuates serotonergic deficits induced by subsequent high-dose methamphetamine administrations.

BACKGROUND: Pre-clinical studies indicate that high-dose, non-contingent methamphetamine (METH) administration both rapidly and persistently decreases serotonergic neuronal function. Despite research indicating the hippocampus plays an important role in METH abuse and is affected by METH use, effects of METH self-administration on hippocampal serotonergic neurons are not well understood, and were thus an important focus of the current study. Because humans often administer METH in a binge-like pattern, effects of prior METH self-administration on a subsequent "binge-like" METH treatment were also examined. METHODS: Rats were treated as described above, and sacrificed 1 or 8d after self-administration or 1h or 7d after the final binge METH or saline exposure. Hippocampal serotonin (5-hydroxytryptamine; 5HT) content and transporter (SERT) function were assessed. RESULTS: METH self-administration per se had no persistent effect on hippocampal 5HT content or SERT function. However, this treatment attenuated the persistent, but not acute, hippocampal serotonergic deficits caused by a subsequent repeated, high-dose, non-continent METH treatment administered 1 d the last self-administration session. No attenuation in persistent deficits were seen when the high-dose administration of METH occurred 15d after the last self-administration session. CONCLUSIONS: The present findings demonstrate that METH self-administration alters serotonergic neurons so as to engender "tolerance" to the persistent serotonergic deficits caused by a subsequent METH exposure. However, this "tolerance" does not persist. These data provide a foundation to investigate complex questions including how the response of serotonergic neurons to METH may contribute to contingent-related disorders such as dependence and relapse.