Citation

Zhou C, Ye L, Luo C, Wang G, Xu P. Resuscitation 2022; 175: 171-172.

Copyright

(Copyright © 2022, Elsevier Publishing)

DOI

10.1016/j.resuscitation.2022.03.031

PMID

35595497

Abstract

We read with interest the paper by Hüser and coworkers comparing the cohort characteristics and outcome of patients with out-of-hospital cardiac arrest (OHCA) attributed to poisoning (P-OHCA) versus patients with OHCA attributed to other medical causes. This study indicated that poisoning was an independent protective factor of good neurological outcome. The authors make a valid point on the importance of prolonged times of resuscitation efforts in P-OHCA patients, we therefore thank the authors for their efforts. However, we question the relationship between P-OHCA and good neurological outcome, and the article has several issues on which we intend to invite the authors' comments.

Firstly, the diagnosis of poisoning was only based on the physician in the field, but not assured by laboratory or other objective parameters, and the etiology of poisoning was presumed and underlying toxicant remained unclear, thus patients with P-OHCA were screened for inclusion without the rigorous fulfillment of diagnostic procedures, which might be an effect modifier for the relationship between P-OHCA and outcomes. Consequently, further study is required to make more definitive diagnoses of poisoning by objective indicators, such as toxicant detection and autopsy.

Secondly, the authors performed a multivariate logistic analysis to calculate the adjusted odds ratios (ORs) of prognostic factors (variables with p < 0.10 in univariate analysis) for survival at hospital discharge with good neurological function, and the multivariate logistic model had 28 prognostic factors while the effective sample size (the number of patients with favorable outcome) for this study was 3618 (Table S3). Due to overparameterisation and overfitting of the model, however, the sample size must not be too large.2
Reasons for restricting sample size include...

Language: en