Related Factors Of Delayed Encephalopathy After Carbon Monoxide Poisoning In Part Areas Of Sichuan Province

Objective:To study the incidence,risk factors and prognosis of delayed-encephalopathy after carbon monoxide poisoning in part areas of Sichuan Province.Methods:(1)Using the electronic or paper questionnaires to collect the incidence and clinical data of patients with acute carbon monoxide poisoning in8 regions(14 hospitals)of Sichuan Province from November 2016 to February2019.Patients with delayed encephalopathy were diagnosed by follow-up 3months after carbon monoxide poisoning,we did statistic the incidence of delayed encephalopathy of acute carbon monoxide poisoning in part area of Sichuan Province.(2)Univariate analysis of the incidence and clinical data of all patients,including:gender,age,coma,coma time,work labor type,the previous medical history/Personal history,first treatment time of hyperbaric oxygen,Glasgow coma score,white blood cell count,high-sensitivity C-reactive protein,Alanine aminotransferase,D-dimer,creatinine,creatine kinase,lactate dehydrogenase,CT/MRI outcome.Multi-factor binary Logistic regression analysis was performed on the indicators that are meaningful in the single factor.We can learn the risk factors of delayed encephalopathy after carbon monoxide poisoning.(3)Patients with delayed encephalopathy were followed up in the first,third,and sixth months after acute carbon monoxide poisoning.We had recorded the patient’s morbidity,treatment plan,and recovery.At the same time,scoring patients symptoms using the modified Rankin scale and Functional independence scale.(4)The statistical methods in the study include:measurement data subject to normal distribution were expressed as mean±standard deviation,using t test(homogeneity of variance)or t’test(heterogeneity of variance);measurement that did not obey normal distribution data were expressed by Md(P25,P75)and used non-parametric tests.Counting data was expressed as a composition ratio,and theχ~2 test or Fisher test of the data of the four tables was used.For comparison of patients’prognosis analysis,the independent sample t test or repeated measurement analysis of variance was used for the comparison,Classification and repeated measurement data were analyzed by Generalized estimating equation(GEE).P value was adjusted by least significant difference after the comparison.The test level(P)was 0.05.Results:(1)A total of 318 patients with acute carbon monoxide poisoning were enrolled in the questionnaire,35 of them were shed.A total of 283 patients were included in the study at last.There were 46 patients(including 6 deaths)with delayed encephalopathy after carbon monoxide poisoning,237(including 2deaths)patients without delayed encephalopathy.The incidence of delayed encephalopathy of acute carbon monoxide poisoning was 16.3%in part areas of Sichuan Province from 2016 to 2019.(2)Univariate analysis showed that age(χ~2=34.21,P<0.001),gender(χ~2=12.911,P<0.001),the previous medical history/Personal history(χ~2=17.286,P<0.001),the first hyperbaric oxygen treatment time(χ~2=20.693,P<0.001),coma(χ~2=19.264,P<0.001),coma time(Z=-8.006,P<0.001),work Labor Type(χ~2=4.179,P=0.048),Glasgow coma score(Z=-6.159,P<0.001),hypersensitive C-reactive protein(Z=-2.637,P=0.008),alanine aminotransferase(Z=-2.669,P=0.008),creatinine(Z=-3.328,P=0.001),lactate dehydrogenase(Z=-1.792,P=0.073),CT/MRI imaging results(χ~2=20.527,P<0.001)were statistically different in patients with and without delayed encephalopathy.Multivariate binary logistic regression model results showed age(OR=0.050,95%CI(0.011,0.216),P<0.001),the first treatment time of hyperbaric oxygen(OR=0.184,95%CI(0.065,0.523),P=0.001),Glasgow coma score(OR=0.159,95%CI(0.043,0.590),P=0.006)and coma time(OR=0.049,95%CI(0.013,0.185),P<0.001)were independent risk factors for delayed encephalopathy.(3)All the functional independence score(F(1.478,57.623)=16.512,P<0.001),the motor function score(F(1.598,62.326)=12.73,P<0.001)and the cognitive function score(F(1.465,57.132)=20.631,P<0.001)of the patients with delayed encephalopathy after carbon monoxide poisoning were improved,when recorded respectively at the first,the third and the sixth month after these patients’being poisoned.By pairwise comparison between any two treatments’duration,all these three scores after treatments of six months were better than those after three months or one month,which was a statistically significant result.By the same means,all these three scores after treatments of three months were better than those after one month,which was not a statistically significant result.Patients’disability(Waldχ~2=40.471,P<0.001)was also improved gradually.By pairwise comparison between any two treatments’duration,the score after treatments of six months was lower than that after three months or one month,which was a statistically significant result.By the same means,the score after treatments of three months was lower than that after one month,which was not a statistically significant result.(4)The difference was statistically significant in mortality,when it differed between the times of the hyperbaric oxygen therapy treatments(namely≤40 times,41-80times and≥81 times)for patients with delayed encephalopathy after carbon monoxide poisoning.The more hyperbaric oxygen treatments were received,the lower the mortality rate was.Conclusions:1.The incidence of delayed encephalopathy of acute carbon monoxide poisoning in part areas of Sichuan Province from 2016 to 2019 was16.3%.2.The risks of developing delayed encephalopathy after carbon monoxide poisoning were higher for patients with older age,more than 24hours of the first hyperbaric oxygenation treatment time,lower Glasgow coma score and longer-time coma.3.Patients with delayed encephalopathy after carbon monoxide poisoning can effectively improve nerve function from three to six months.4.Increasing the number of times for hyperbaric oxygen therapy can effectively reduce the mortality rate in patients with delayed encephalopathy after carbon monoxide poisoning.