Analysis of prognosis of neurological sequelae in children with carbon monoxide poisoning

This study retrospectively analyzed children admitted to the Fourth Affiliated Hospital of Guangxi Medical University for CO (carbon monoxide) poisoning from January 2018 to December 2022 and followed up on their neurological sequelae for a long time. The study was approved by the Ethics Committees of the Fourth Affiliated Hospital of Guangxi Medical University (the identification code was KY2023131) and informed consent was obtained from all participants and/or their legal guardians. The study complied with the Declaration of Helsinki. Through Global Deterioration Scale [GDS], we further compared the differences between children with and without cognitive impairment, and identified some risk factors for long-term cognitive impairment in children after CO poisoning. The GDS score of the patient was based on the follow-up score, and we only conducted one follow-up and recorded the GDS score throughout the entire study period. The follow-up time interval is defined as the time from the first discharge of the patient to our follow-up. A total of 113 children were encompassed in the study, with an average follow-up of 3.6 years (3.6 ± 1.5 years). Among them, 13 children (11.5%, 13/113) had cognitive abnormalities. The utilization of gas water heaters in enclosed bathrooms (101 cases, 89.4%) constituted the most frequent cause of CO poisoning among children in this study, followed by heating with fire (11 cases, 9.7%). Furthermore, one child was left by his father in a running car, thereby resulting in poisoning. The clinical manifestations of CO poisoning in children were mainly consciousness disorders (67 cases, 59.3%), dizziness or headache (37 cases, 32.7%), and other manifestations including irritability, crying, vomiting, limb weakness, and limb twitching, a total of 9 cases. The duration of consciousness disorders in children with cognitive abnormalities was mostly more than one day, with a median of 5 days, and the hospitalization time was longer. Children with cognitive abnormalities had higher C-reactive protein (CRP) levels, higher D-dimer levels, and higher liver enzyme levels. The most common imaging change after CO poisoning in children was cerebral edema, with two cases of subarachnoid hemorrhage observed and one case of demyelinating changes observed. For children with coma time less than one hour, there were few abnormal changes in cranial imaging. Children with cognitive abnormalities were more likely to develop epilepsy (38.5%, 5/13) and other system damage (53.8%, 7/13) during hospitalization, including pulmonary infection (3 cases), stressful gastrointestinal bleeding (2 cases), electrolyte imbalance (2 cases), dysfunction of liver, kidney or myocardial (3 cases), and some children had multiple system damage at the same time. There were statistical differences in the admission CO hemoglobin level, fibrinogen, D-dimer, high-sensitivity CRP, neuron enolase, alanine aminotransferase or aspartate aminotransferase (ALT or AST), lactate dehydrogenase, length of hospital stay, discharge and admission Glasgow Coma Scale (GCS), seizure frequency, duration of consciousness disorders more than one day, cranial imaging changes, use of ventilators, presence of other system damage, the number of hyperbaric oxygen (HBO) treatments, and whether the patients were transferred to another hospital between the two groups of children. Multivariate logistic regression analysis showed that head imaging changes and consciousness disorders lasting for more than a day were statistical differences. For children with unconsciousness lasting for more than one hour, it is advisable to contemplate conducting a head imaging examination as soon as possible within 3 days after CO exposure to guide the treatment during the acute phase.Characteristic alterations in cranial imaging and a longer duration of consciousness disorders (exceeding one day) might be correlated with subsequent neurological sequelae. For children with CO poisoning presenting these characteristics, active treatment can be implemented, encompassing but not restricted to HBO treatments, to minimize subsequent damage to the greater extent possible. So, for children who were unconscious for more than one day or presented characteristic changes in cranial imaging, long-term follow-up should be carried out to determine whether delayed encephalopathy or subsequent cognitive impairment occurs.