Assessing the Impact of 3% Hypertonic Saline Hyperosmolar Therapy on Intubated Children With Isolated Traumatic Brain Injury by Cerebral Oximetry in a Pediatric Emergency Setting

Prehospital Hypertonic Saline Administration After Severe Traumatic Brain Injury

A 25-year old male paient was critically injuried in a high speed motor vehicle collision over an hour from the nearest trauma center. Paramedics diagnosed the patient with a traumatic brain injury and increasing intracranial pressure and transported the patient to a predesignated landing zone for helicopter intercept. During transport paramedics initiated a severe traumatic brain injury protocol which included the adminisration of 3% hypertonic saline. The flight crew continued 3% hypertonic saline managment which was later transferred to the receiving trauma team. Upon trauma center arrival the patient was diagnosed with a skull fracture and subdural hematoma. The patient was transitioned to a 3% hypertonic saline infusion for the next 24 h. The need for integrating systems of care is particularly important when managing patients with severe traumatic brain injury. This case report describes a patient with a severe TBI who received prehospital 3% hypertonic saline based on an integrated protocol developed between multiple prehosptial systems and a tertiary care trauma center. Severe traumatic brain injuries (TBIs) are a potentially catastrophic event, and morbidity can rise precipitously without early interventions to prevent hypoxia and hypotension and control for rising intracranial pressure. In recent years, hypertonic saline (HTS) has shown efficacy in lowering intracranial pressures for patients experiencing TBIs, the leading cause of death and disability among children and young adults in the United States.¹ Integrating care between health care providers across the acute care continuum, from prehospital systems to discharge, is paramount in providing the best patient outcomes possible, especially in health care system expansions such as air medical transport. The need for integrating systems of care is particularly important when managing patients with severe TBI. Statewide prehospital care protocols vary greatly; 78% provide ventilation guidance, 77.3% have targeted end-tidal carbon dioxide levels below < 35 mm Hg, and only 1 (of 38 reviewed) includes HTS (3%).² One barrier to consistency in protocol development is the available literature. One trial demonstrated that a prehospital bolus of 7.5% HTS in severe TBI did not improve mortality.³ However, the Brain Foundation guidelines continue to recommend the prehospital use of hyperosmolar therapy for patients with severe TBI and evidence of impending herniation.⁴ Hyperosmolar therapy is also recommended as an inpatient strategy for lowering increased intracranial pressure (ICP).⁴ One reason for this apparent disconnect is because the ideal timing of HTS administration and its concentration have not been determined.⁴ A meta-analysis previously determined no one prehospital fluid is superior to another in improving the outcomes of patients with severe TBI.⁵ However, none of the reviewed research investigated the continued use of HTS across an integrated system of care. This case report describes a patient with a severe TBI who received 3% HTS initiated in the prehospital setting with the infusion continued upon arrival at the trauma center using a system-wide integrated protocol.

Comparison of Intracranial Pressure Measurements Before and After Hypertonic Saline or Mannitol Treatment in Children With Severe Traumatic Brain Injury

IMPORTANCE

Hyperosmolar agents are cornerstone therapies for pediatric severe traumatic brain injury. Guideline recommendations for 3% hypertonic saline (HTS) are based on limited numbers of patients, and no study to date has supported a recommendation for mannitol.

OBJECTIVES

To characterize current use of hyperosmolar agents in pediatric severe traumatic brain injury and assess whether HTS or mannitol is associated with greater decreases in intracranial pressure (ICP) and/or increases in cerebral perfusion pressure (CPP).

DESIGN, SETTING, AND PARTICIPANTS

In this comparative effectiveness research study, 1018 children were screened and 18 were excluded; 787 children received some form of hyperosmolar therapy during the ICP-directed phase of care, with 521 receiving a bolus. Three of these children were excluded because they had received only bolus administration of both HTS and mannitol in the same hour, leaving 518 children (at 44 clinical sites in 8 countries) for analysis. The study was conducted from February 1, 2014, to September 31, 2017, with follow-up for 1 week after injury. Final analysis was performed July 20, 2021.

INTERVENTIONS

Boluses of HTS and mannitol were administered.

MAIN OUTCOMES AND MEASURES

Data on ICP and CPP were collected before and after medication administration. Statistical methods included linear mixed models and corrections for potential confounding variables to compare the 2 treatments.

RESULTS

A total of 518 children (mean [SD] age, 7.6 [5.4] years; 336 [64.9%] male; 274 [52.9%] White) were included. Participants' mean (SD) Glasgow Coma Scale score was 5.2 (1.8). Bolus HTS was observed to decrease ICP and increase CPP (mean [SD] ICP, 1.03 [6.77] mm Hg; P < .001; mean [SD] CPP, 1.25 [12.47] mm Hg; P < .001), whereas mannitol was observed to increase CPP (mean [SD] CPP, 1.20 [11.43] mm Hg; P = .009). In the primary outcome, HTS was associated with a greater reduction in ICP compared with mannitol (unadjusted β, -0.85; 95% CI, -1.53 to -0.19), but no association was seen after adjustments (adjusted β, -0.53; 95% CI, -1.32 to 0.25; P = .18). No differences in CPP were observed. When ICP was greater than 20 mm Hg, greater than 25 mm Hg, or greater than 30 mm Hg, HTS outperformed mannitol for each threshold in observed ICP reduction (>20 mm Hg: unadjusted β, -2.51; 95% CI, -3.86 to -1.15, P < .001; >25 mm Hg: unadjusted β, -3.88; 95% CI, -5.69 to -2.06, P < .001; >30 mm Hg: unadjusted β, -4.07; 95% CI, -6.35 to -1.79, P < .001), with results remaining significant for ICP greater than 25 mm Hg in adjusted analysis.

CONCLUSIONS AND RELEVANCE

In this comparative effectiveness research study, bolus HTS was associated with lower ICP and higher CPP, whereas mannitol was associated only with higher CPP. After adjustment for confounders, both therapies showed no association with ICP and CPP. During ICP crises, HTS was associated with better performance than mannitol.