# Incidence and risk factors for cardiac arrest following upper cervical spine fractures in the elderly after minor trauma

## TL;DR

This study finds that upper cervical spine fractures in elderly patients after minor trauma can lead to cardiac arrest, with specific risk factors identified.

## Contribution

The study provides new insights into the incidence and risk factors for cardiac arrest following upper cervical spine fractures in the elderly.

## Key findings

- OHCA incidence was 9.9% in elderly patients with upper cervical spine fractures.
- Younger age, Anderson type II odontoid fracture, and nighttime trauma significantly predicted OHCA.
- Non-shockable rhythms like PEA and asystole were common in resuscitated patients.

## Abstract

Cardiac etiologies are one of the main causes for out of hospital cardiopulmonary arrest (OHCA). Other etiologies might be easily overlooked, leading to delayed causal treatment. One such representative is neurogenic shock following upper cervical spine fractures after minor impact trauma in the elderly with little data on prevalence and risk factors, a drawback that we address in the present study.

Between 01/2013 and 12/2023, all patients ≥ 65 years with a fracture of the first and/or second vertebra after minor impact trauma were retrospectively reviewed to evaluate the incidence and character of OHCA. Resuscitated and non-resuscitated patients were compared regarding risk factors such as age, BMI, fracture classification and displacement, cardiac illness, laboratory parameters and bone mineral density.

Final data included 141 patients, 82.5 ± 7.6 years; 73 female and 68 male. The OHCA incidence was 9.9%. Pulseless electrical activity (PEA) (71,4%) and asystole (28.6%) were the only initial cardiac rhythms in these resuscitated patients. Patients were resuscitated for 14.4 ± 9.5 min before the return of spontaneous circulation (ROSC). The in-hospital survival rate was 21.4% (n = 3). Younger patient age (OR0.992 per year), a Anderson type II odontoid fracture (OR 1.145), as well as trauma during nighttime (6 pm–7am) significantly predicted OHCA (p < 0.05). Sex, BMI, bone density, fracture displacement and laboratory parameters (serum electrolytes (Sodium and Potassium), Lactate, pH, Hemoglobin, and Creatinine) revealed no direct impact on the likelihood to suffer from OHCA.

With an occurrence of almost 10%, OHCA resulting from an upper cervical spine injury following low impact trauma is frequent in the elderly patient, and appears to be associated with non-shockable primary rhythms (PEA or asystole). If cardiac output is successfully restored, clinicians should always exclude an upper cervical spine fracture (especially an odontoid fracture). We therefore recommend an interdisciplinary primary assessment and cervical spine immobilization.