Impact of Cervical Spine Management Brain Injury on Functional Survival Outcomes in Comatose, Blunt Trauma Patients with Extremity Movement and Negative Cervical Spine CT: Application of the Monte Carlo Simulation

Abstract

Cervical spine (CS) magnetic resonance imaging (MRI) and collar use may prevent quadriplegia, yet create brain injury. We developed a computer model to assess the effect of CS management strategies on outcomes in comatose, blunt trauma patients with extremity movement and a negative CS CT scan. Strategies include early collar removal (ECR), ECR & MRI, late collar removal (LCR), and LCR & MRI. MRI risks include hypoxia, hypotension, increased intracranial pressure (↑ICP), and ventilator-associated pneumonia (VAP). LCR risks include ↑ICP, VAP, and delirium. Model elements include Quadriplegia and Primary, Secondary, LCR, and MRI Brain Injury. The Monte Carlo simulation determines health outcomes (Functional Survival versus Quadriplegia, Severe Brain Disability, or Dead). Utility values are Functional Survival 0.90, Quadriplegia 0.20, Severe Brain Disability 0.10, and Dead 0.00. Years of life expectancy are Functional Survival 39.5, Quadriplegia 20.0, Severe Brain Disability 20.0, and Dead 0.0. Unstable CS rate 2.5%: Functional Survival/1,000: Unstable Patients: ECR 384, LCR 350, LCR & MRI 332, ECR & MRI 331; High-Risk Patients: ECR 161, LCR 151, LCR & MRI 140, ECR & MRI 153; Stable Patients: ECR 596, LCR 587, LCR & MRI 573, ECR & MRI 595. Quality-Adjusted Life Months for Unstable, High-Risk, and Stable Patients are greater with ECR; Stable Patient ECR and ECR & MRI are similar. Unstable CS rate 0.5%: Functional Survival/1000: Unstable Patients: ECR 394, LCR 352, LCR & MRI 332, ECR & MRI 332; High-Risk Patients: ECR 164, LCR 151, LCR & MRI 140, ECR & MRI 152; Stable Patients: ECR 611, LCR 592, LCR & MRI 576, ECR & MRI 598. Quality-Adjusted Life Months for Unstable, High-Risk, and Stable Patients are greater with ECR. LCR and MRI brain injury results in losses of functional survivorship that exceed those from quadriplegia. Model results suggest that early collar removal without cervical spine MRI is a reasonable, and likely the preferable, cervical spine management strategy for comatose, blunt trauma patients with extremity movement and a negative cervical spine CT scan.