Characteristics of the most severely ill and injured patients in a Norwegian Helicopter Emergency Medical Service: A retrospective cohort study

Abstract

Bakgrunn Legebemannet luftambulanse i Norga kalles ut til et bredt spekter hendelser, fra mindre alvolige til livstruende. Ferdihetene en lege tilbyr kan være viktige for å tilby adekvat helsehjelp til de meste skadde- og syke pasientene. En bedre forståelse av disse pasientene kan derfor være viktig for å optimalisere varslingskriterier, trening og utstyrskonfigurasjon for luftambulansen. Målet til denne studien er å beskrive de dårligste pasientene som behandles i luftambulansen. De vil beskrives med hensyn til diagnosegruppe og intervensjoner.

Metode Retrospektiv cohort-studie på oppsamlede data fra luftambulansebasen i Trondheim, Norge. Alle pasienter med national advisory committee on aeronautics (NACA) score 5 og 6, i perioden 2013 - 2022 ble inkludert. Pasienter med return of spontaneous circulation (ROSC) etter velykket gjenopplivning ble beskrevet som en egen gruppe.

Resultater Av 9546 pasienter behandlet av luftambulansetjenesten i Trondeim, ble 2598 inkludert. 1640 NACA 5 og 958 NACA 6. Pasientenes medianalder var 64 (Variasjonsbredde i kvartiler 45-75) og 64% av pasienten var menn. Post-ROSC-pasienter utgjorde 24% av pasientene. Av de øvrige pasientene var den største diagnosegruppen traume (16%), hjerte (15%), nevrologi (14%) og respirasjon (11%). Intervensjonene gitt til høyeste andel pasienter var generell anestesi (22%), intubasjon (21%), arteriekran (21%) og ventilatorbehandling (18%). Gjennomsnittlig antall intervensjoner per oppdrag var konsistent gjennom studieperioden (1,78, SD 0,25).

Konklusjon Kompetansen som en legebemannet luftambulansetjeneste tilbyr er til nytte for et høyt antall alvorlig syke- og skadde pasienter.

Abstract Background Physician-staffed helicopter emergency medical services (HEMS) are dispatched to a variety of incidents, ranging from less serious to life-threatening. The skillset of a physician may be important to provide appropriate care for the most critically ill and severely injured patients. A better understanding of these patients may therefore be important to optimize dispatch criteria, training, and equipment setups for HEMS units. The aim of this study was to describe the characteristics of patients with the national advisory committee on aeronautics (NACA) score 5 and 6, primarily by diagnostic group and interventions performed.

Methods Retrospective cohort study on aggregated data from the HEMS-base in Trondheim, Norway. All patients with NACA score 5 and 6 in the ten-year period from 2013 to 2022 were included. Patients with return of spontaneous circulation (ROSC) after successful cardiopulmonary resuscitation were described separately from non-cardiac arrest patients.

Results Out of 9546 patient encounters, 2598 patients were included, with 1640 in the NACA 5 and 958 in NACA 6 group. Patient age was median 63 (interquartile range 45-74) and 64% of the patients were male. Post-ROSC patients accounted for 24% of patients. Of the non-cardiac arrest patients, the most frequent aetiology was trauma (16 %), cardiac (15 %), neurologic (14 %) and respiratory (11 %). The most common physician-requiring advanced interventions were general anaesthesia (22 %), intubation (21 %), invasive blood pressure monitoring (21 %) and ventilator treatment (18 %). The mean number of advanced interventions per mission were consistent during the study period (1,78, SD 0,25).

Conclusion Twenty-seven percent of all HEMS dispatches were to NACA 5 and 6 patients. Twenty-four percent of these were post-ROSC patients. Sixty-three percent of all patients received at least one advanced physician-requiring intervention and the average number of interventions were consistent during the last ten years. Hence, the competence a physician-staffed HEMS resource provide is utilized in a high number of critically ill and injured patients.