الفهرس 
REVIEW OF LITERATUREOnly 14 pages are availabe for public view
Abstract
C
arbon monoxide poisoning is one of the most frequent intoxications in the world. It is produced by incomplete combustion of carbonaceous substances. Exposure to high levels of CO may induce tissue hypoxia, cause tissue injury and even death.
Cardiac toxicity after CO poisoning includes arrhythmias, heart failure and myocardial infarction. As these cardiac injuries may increase mortality in patients with CO poisoning, it is very important to detect cardiac injuries at the emergency department. However, the prevalence and clinical course in patients with acute CO poisoning has been insufficiently reported.
The current study was carried out on 30 patients admitted to the PCC-ASUH with moderate or severe acute CO poisoning during the period from the beginning of October 2018 to the end of March 2020.
The aim of this study was to assess the role of Pentraxin 3 and B type natriuretic peptide in comparison with cardiac Troponin I as early predictor biomarkers of cardiotoxicity in patients presented with acute CO poisoning to the PCC-ASUH.
The current study showed that the majority of cases were males with mean age 35.40 ± 13.33 years. Most of the cases were from Cairo (86.7%), while (13.3%) of the cases were from Giza.
As regard the intoxication data, all patients included in the current study were accidentally exposed to CO poisoning by inhalation. Most of the patients (83.3 %) were exposed to CO poisoning at home. Concerning the seasonal variation, the majority of cases were exposed to CO poisoning mainly in winter. The duration of exposure to CO poisoning ranged between 1-2 hours. The mean delay time in the current study was 4.19 ± 1.73 hours.
According to hospital disposition most of the patients were admitted in the ICU of PCC-ASUH (60%) with severe CO toxicity, while 40% of the patients were admitted in the in-patient department with moderate CO toxicity.
As regard the manifestations before and on admission of acute CO poisoned patients in the current study, all the patients were presented with vomiting. Headache was found in 33.3 % of the patients. Only 6.7% of the patients were presented with difficulty in breathing.
In the current study, the conscious level was assessed by Reed′s scale where 60% of the patients had disturbed conscious level and 33.3% of the patients were conscious. Most of comatose patients were in coma grade I (30%).
Regarding the vital data, most of the patients (56.7%) were normotensive. Tachycardia was presented in 86.7 % of the patients. All patients had normal body temperature. Concerning the respiratory rate, the majority of the patients were presented with normal respiratory rate (86.7%), and only (13.3%) of the patients were presented with tachypnea.
As regards the cardiovascular manifestations, (16.7%) of the patients had signs of shock. Concerning the respiratory system manifestations, (60%) of the patients required mechanical ventilation. Abnormal pattern of breathing was detected in (6.7%) of the patients and (23.3%) of the patients had adventitious sounds. Regarding the gastrointestinal manifestations, vomiting was observed in all patients included in the current study.
In the present study, comparison was done between the first and the second serum samples of cardiac biomarkers that include Troponin I, Pentraxin 3 and BNP. Significant relation was found between the first and the second serum samples of Troponin I and BNP. While no relation was found between the first and the second serum samples of Pentraxin 3.
In the current study, significant relation was found between the first and the second serum samples of cardiac biomarkers in acute CO poisoning cases in comparison with the control group.
Negative correlation was found between the first serum levels of Troponin I and the duration of exposure and between the first serum levels of Pentraxin 3 and the partial pressure of oxygen. In addition, negative correlation was also found between the second serum levels of BNP, the bicarbonate level and base deficit. While positive correlation was reported between the first serum levels of Pentraxin 3 with COHb level.
Receiver Operating characteristic curve was applied to analyze the sensitivity and the specificity of the first and the second serum samples of cardiac biomarkers in predicting the cardiotoxicity in acutely CO poisoned patients in the current study.
Concerning the first serum samples of the cardiac biomarkers, it was found that the best cut off point of serum levels of Troponin I, Pentraxin 3and BNP were more than 0.8 ng/mL , 3 ng/mL and 160 ng/L respectively.
The cut off level of > 0.8 ng/mL of the first serum samples of Troponin I achieved 96.67 % sensitivity and 85.71% specificity. While, the cut off level of >3 ng/ mL of the first serum samples of Pentraxin 3 achieved 83.3 % sensitivity and 89.29 % specificity to discriminate between CO poisoning cases with cardiotoxicity and the control group.
As regards the first serum samples of BNP, it was found that the cut off level >160 ng/ L achieved 96.6 % sensitivity and 100 % specificity. This cut off point had the best positive predictive value and negative predictive value to discriminate between CO poisoning cases with cardiotoxicity and the control group, in comparison with the first serum levels of Troponin I and Pentraxin 3.
As regard the second serum samples of cardiac biomarkers, it was found that the best cut off point of Troponin I, Pentraxin 3 and BNP were >0.8 ng/mL , >3 ng/mL and >120 ng/L respectively.
The cut off level of > 0.8 ng/mL of the second serum samples of Troponin I achieved 50 % sensitivity and 100 % specificity to discriminate between CO poisoning cases with cardiotoxicity and the control group.
The cut off level of >3 ng/ mL of the serum level of the second serum sample of Pentraxin 3 achieved 66.6 % sensitivity and 89.92 % specificity to discriminate between CO poisoning cases with cardiotoxicity and the control group.
As regard the second serum samples of BNP, it was found that cut off level >120 ng/ L achieved 93.33% sensitivity and 82.14 % specificity to discriminate between CO poisoning cases with cardiotoxicity and the control group.
This mean that, the cut off level > 0.8 ng/mL of the second serum samples of Troponin I had the best specificity to discriminate between CO poisoning cases with cardiotoxicity and the control group. Also cut off level >120 ng/ L of the second serum samples of BNP had the best sensitivity to discriminate between CO poisoning cases with cardiotoxicity and the control group.
As regards the outcome of the patients in the current study, (83.3%) of the patient were recovered and (16.7%) of the patients were died.
Concerning the correlation between the outcome and the cardiac biomarkers, no significant correlation was found between the cardiac biomarkers and the outcome of acutely CO poisoned patients.
This study found that, the first serum samples of BNP had the best positive predictive value and negative predictive value to discriminate between CO poisoning cases with cardiotoxicity and the control group, in comparison with the first serum levels of Troponin I and Pentraxin 3.
The second serum samples of Troponin I with cut off level > 0.8 ng/mL had the best specificity to discriminate between CO poisoning cases with cardiotoxicity and the control group. Also cut off level >120 ng/ L of the second serum samples of BNP had the best sensitivity to discriminate between CO poisoning cases with cardiotoxicity and the control group.
In addition serum Pentraxin 3 level had the least specificity and sensitivity to discriminate between CO poisoning cases with cardiotoxicity and the control group in comparing with Troponin I and BNP.
According to the results of the current study, further prospective studies involving large number of patients are needed to evaluate the role of cardiac biomarkers as Troponin I, Pentraxin 3 and BNP in predicting the cardiotoxicity in acute CO poisoning.