Do pre‐hospital anaesthesiologists reliably predict mortality using the NACA severity score? A retrospective cohort study

Abstract

IntroductionThe National Advisory Committee on Aeronautics' (NACA) severity score is widely used in pre-hospital emergency medicine to grade the severity of illness or trauma in patient groups but is scarcely validated. The aim of this study was to assess the score's ability to predict mortality and need for advanced in-hospital interventions in a cohort from one anaesthesiologist-manned helicopter service in Northern Norway.MethodsAll missions completed by one helicopter service during January 1999 to December 2009 were reviewed. One thousand eight hundred forty-one patients were assessed by the NACA score. Pre-hospital and in-hospital interventions were collected from patient records. The relationship between NACA score and the outcome measures was assessed using receiver operating characteristic (ROC) curves.ResultsA total of 1533 patients were included in the analysis; uninjured and dead victims were excluded per protocol. Overall mortality rate of the patients with NACA score 1–6 was 5.2%. Trauma patients with NACA score 1–6 had overall mortality rate of 1.9% (12/625) and non-trauma patients 7.4% (67/908). The NACA score's ability to predict mortality was assessed by using ROC area under curve (AUC) and was 0.86 for all, 0.82 for non-trauma and 0.98 for trauma patients. The NACA score's ability to predict a need for respiratory therapy within 24 h revealed an AUC of 0.90 for all patients combined.ConclusionThe NACA score had good discrimination for predicting mortality and need for respiratory therapy. It is thus useful as a tool to measure overall severity of the patient population in this kind of emergency medicine system.

Helicopter‐based emergency medical services for a sparsely populated region: A study of 42,500 dispatches

“…The NACA score is a crude scale but is reported to be useful for predicting mortality and the need for early respiratory therapy 20. Applying NACA, we showed that one third of the patients in our primary missions were severely ill or injured (NACA 5–7).…”

“…All external impacts causing injury were classified as trauma, including drowning, foreign body airway obstruction, and cardiac arrest caused by trauma. Patients were already categorized according to the NACA severity score 19, 20. Missing NACA scores in table, 827 (3.3%).…”

“…Activation time were defined as time from dispatch to helicopter take‐off or car moving, response time from dispatch to encountering the patient, on‐scene time from encountering the patient to start of patient transport from the scene, and transport time from start of patient transport from scene to end of patient care. The National Advisory Committee for Aeronautics score (NACA, Supplemental files, Table S1) was modified to be used for pre‐hospital medical emergencies and trauma in 1980 19, 20. This severity score from level 0 (no injury or disease) to level 7 (death) is used in Norwegian HEMS.…”

Helicopter Emergency Medical Services Response Times in Norway: Do They Matter?

“…The data included the municipality where the mission was flown, the flying time taken to reach the scene from where the helicopter was positioned when requested, and the National Committee on Aeronautics (NACA) score for each patient. 21 NACA is an international severity score that is often used within the air medical society to grade the severity of the illness using values ranging from 0 (no health problems) to 7 (death) ( Table 1). 21 The score assigned to every transported patient within the National Air Ambulance service gives an estimate of the level of patients' clinical severity as evaluated by the treating physician.…”

Pain Management Strategies and Time Spent on Scene for Pre-Hospital Analgesia Provision in an Alpine Environment: A Retrospective Study

“…Injury severity was graded according to the 8-level National Advisory Committee for Aeronautics (NACA) scale from zero (no injury) to seven [6]. Pain intensity was assessed at the scene and at the hospital using the 11-point Verbal Numeric Rating Scale (VNRS), which ranges from no pain (VNRS=0) to the worst pain possible (VNRS=10).…”