# Predictive Ability of the Classification of Ground Level Falls As Syncopal Versus Mechanical in a Mixed Intensive Care Unit Population: A Retrospective Cohort Study

## TL;DR

This study found that classifying falls as syncopal or mechanical in ICU patients helps predict outcomes like mortality and cardiovascular issues.

## Contribution

The study demonstrates that syncopal fall classification is a novel predictor of mortality and cardiovascular conditions in ICU patients.

## Key findings

- Syncopal falls were associated with lower mortality compared to mechanical falls.
- Syncopal falls were linked to higher rates of arrhythmia and need for pacemaker implantation.
- Cardiovascular conditions were more common in syncopal fall patients but also prevalent in mechanical fall cases.

## Abstract

Introduction

Ground-level falls are a common mechanism of trauma, especially in the elderly. They are typically classified by etiology as syncopal or mechanical, based on a report of syncope (loss of consciousness due to transient reduction of cerebral blood flow). Syncopal falls generally prompt an evaluation of the cause of syncope, but the utility of this investigation and hence this classification system remains uncertain.

Methods

This retrospective registry review compares outcomes for patients with falls classified as syncopal versus mechanical. The data source is the Medical Information Mart for Intensive Care (MIMIC) III database. Patients experiencing a fall documented in the history of present illness (HPI) or during the admission were included. Syncopal versus mechanical etiology was analyzed as a predictive factor for length of stay, mortality, and cardiovascular and neurologic outcomes. Significance for categorical variables was tested with a chi-square and continuous variables with a T-test. Multivariate analysis was performed with logistic regression for binary outcomes and linear regression for continuous outcomes.

Results

Overall mortality for mechanical falls was 384 (54.2%) versus 480 (45.2%) for syncopal (p<0.001). Conditions more common among the syncopal group include cardiac valve disorder - 151 (14.2%) versus 76 (10.7%) (p=0.038), arrhythmia - 540 (50.8%) versus 322 (45.5%) (p=0.03), orthostatic hypotension - 38 (3.6%) versus 8 (1.1%) (p=0.003), and need for pacemaker implant or revision - 87 (8.2%) versus 13 (1.8%) (p<0.001). The difference in myocardial infarction was not significant. Syncopal etiology was an independent predictor of outcomes including overall mortality - adjusted odds ratio (OR) 0.75 (p=0.005), gastrointestinal bleed- (OR) 1.74 (p=<0.001), orthostatic hypotension - OR 3.34 (p=0.002), and need for pacemaker placement or revision - OR 4.0 (p<0.001).

Conclusion

Mortality was lower for patients with syncopal falls. Cardiovascular conditions were significantly more common among syncopal fall patients, but the incidence, especially for arrhythmia, was high and nearly equal in the mechanical group. We believe that a standard workup for orthostasis and arrhythmia should be performed for both groups, regardless of syncopal versus mechanical etiology.