Lack of pupil reflex and loss of consciousness predict 30-day neurological sequelae in patients with carbon monoxide poisoning.
BACKGROUND
Predicting the neurological sequelae of carbon monoxide poisoning (COP) has not been well studied. We investigated the independent predictors of neurological sequelae in patients with COP and combined these predictors to predict the prognosis.


METHODS
This study was conducted at four hospitals in Shandong Province, China. Data were retrospectively collected from 258 patients with COP between November 1990 and October 2011. Thirty-day neurological sequelae were the primary endpoints.


RESULTS
A lack of pupil reflex and a loss of consciousness appear to be independent predictors for neurological sequelae in patients with COP. The presence of either one had a sensitivity of 77.0% (95% confidence interval [CI]: 69.3-83.2), a specificity of 47.1% (95% CI: 38.3-56.0), positive predictive value (PPV) of 62.9% (95% CI: 55.2-70.1), and a negative predictive value (NPV) of 63.6% (95% CI: 52.6-73.4). With both predictors present, the sensitivity was 11.5% (95% CI: 6.9 to 18.3), the specificity was 99.2 (95% CI: 94.7-100.0), the PPV was 94.1% (95% CI: 69.2-99.7), and the NPV was 49.0% (95% CI: 42.5-55.5).


CONCLUSIONS
The risk for neurological sequelae apparently increased with the number of independent predictors. In patients with both predictors, the risk for neurological sequelae was 94.1%. Almost all (99.2%) patients with neither predictor had no neurological sequelae. This finding may help physicians make decisions about and dispositions for patients with COP. For patients with a higher risk, earlier treatment and more appropriate utilization of health care services, including hyperbaric oxygen, should be considered.
Clinical Division of Occupational Medicine, Institute of Occupational Health and Occupational Medicine, Academy of Medical Science, Shandong Province, China.
Jian-Fang
JF
Zou
Clinical Division of Occupational Medicine, Institute of Occupational Health and Occupational Medicine, Academy of Medical Science, Shandong Province, China.
Qiming
Q
Guo
Clinical Division of Occupational Medicine, Institute of Occupational Health and Occupational Medicine, Academy of Medical Science, Shandong Province, China.
Hua
H
Shao
Division of Toxicology, National Institute of Occupational Health and Poison Control, Beijing, China.
Bin
B
Li
Department of Medicine, Second People's Hospital of Dongying, Shandong Province, China.
Yuxiu
Y
Du
Department of Medicine, Qilu Petrochemical Corporation Hospital, Shandong Province, China.
Maofeng
M
Liu
Department of Medicine, Qilu Petrochemical Corporation Hospital, Shandong Province, China.
Fengling
F
Liu
Department of Medicine, Second People's Hospital of Kenli, Shandong Province, China.
Lixin
L
Dai
Department of Emergency Medicine, Chi-Mei Medical Center, Tainan, Taiwan; Department of Biotechnology, Southern Taiwan University of Science and Technology, Tainan, Taiwan; Department of Emergency Medicine, Taipei Medical University, Taipei, Taiwan.
Hung-Jung
HJ
Lin
Department of Occupational Medicine, Chi-Mei Medical Center, Tainan, Taiwan; Department of Leisure, Recreation, and Tourism Management, Southern Taiwan University of Science and Technology, Tainan, Taiwan; Department of Medical Research, Chi Mei Medical Center, Liouying, Tainan, Taiwan.
Shih-Bin
SB
Su
Department of Environmental and Occupational Health, College of Medicine, National Cheng Kung University, Tainan, Taiwan; Department of Occupational and Environmental Medicine, National Cheng Kung University Hospital, Tainan, Taiwan.
How-Ran
HR
Guo
Department of Emergency Medicine, Chi-Mei Medical Center, Tainan, Taiwan; Department of Environmental and Occupational Health, College of Medicine, National Cheng Kung University, Tainan, Taiwan; Department of Child Care and Education, Southern Taiwan University of Science and Technology, Tainan, Taiwan; Department of Emergency Medicine, Kuo General Hospital, Tainan, Taiwan.
Chien-Cheng
CC
Huang
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002249:Carbon Monoxide Poisoning / Q000150:complications* / Q000175:diagnosis / Q000503:physiopathology*; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012025:Reflex, Pupillary; D012189:Retrospective Studies; D014474:Unconsciousness / Q000150:complications*; D055815:Young Adult