Long-term outcome of delayed neuropsychiatric sequelae after carbon monoxide poisoning

Yoo, Joo Young; Kim, Gap Teog; Koh, Chan Young

Abstract

OBJECTIVE
Delayed neuropsychiatric sequelae (DNS) following carbon monoxide (CO) poisoning, which may result from a demyelinating leukoencephalopathy, is a disease with a poor prognosis. This study examined the factors affecting the long-term prognosis of DNS and the efficacy of hyperbaric oxygen therapy (HBOT) in patients with DNS.
METHODS
This retrospective study included 84 patients with DNS following CO poisoning from January 2013 to June 2016. HBOT was given to 24 patients. The patients were divided into an improvement group and non-improvement group based on their clinical condition on a telephone interview at intervals between 3 months and 3 years after the onset of DNS. The improvement group was defined as having Cerebral Performance Category (CPC) scores in their daily life that improve to 1 or 2 grade.
RESULTS
Of the 594 patients, DNS were found in 18.2%, and 70.2% (59 of 84) of the patients with DNS improved. The prognostic factors for the improvement of DNS were an age of 45 years or less (odds ratio [OR], 12.068; 95% confidence interval [CI], 2.393-60.858; P < 0.005), CPC score of 1 or 2 group at the time of DNS onset (OR, 12.361; 95% CI, 3.161-48.330; P < 0.005), and a lucid interval longer than 20 days (OR, 5.164; 95% CI, 1.393-19.141; P < 0.01). HBOT was not associated with the improvement of DNS in CO poisoning (OR, 0.467; 95% CI, 0.172-1.269; P>0.1).
CONCLUSION
Patients aged less than 45 years, low grade CPC score of 1 and 2, and lucid interval longer than 20 days are more likely to have a good prognosis. On the other hand, HBOT failed to produce a benefit for DNS patients.