Predicting poor outcome in patients with intentional carbon monoxide poisoning and acute respiratory failure: A retrospective study

Carbon Monoxide Poisoning: From Microbes to Therapeutics

Carbon monoxide (CO) poisoning leads to 50,000-100,000 emergency room visits and 1,500-2,000 deaths each year in the United States alone. Even with treatment, survivors often suffer from long-term cardiac and neurocognitive deficits, highlighting a clear unmet medical need for novel therapeutic strategies that reduce morbidity and mortality associated with CO poisoning. This review examines the prevalence and impact of CO poisoning and pathophysiology in humans and highlights recent advances in therapeutic strategies that accelerate CO clearance and mitigate toxicity. We focus on recent developments of high-affinity molecules that take advantage of the uniquely strong interaction between CO and heme to selectively bind and sequester CO in preclinical models. These scavengers, which employ heme-binding scaffolds ranging from organic small molecules to hemoproteins derived from humans and potentially even microorganisms, show promise as field-deployable antidotes that may rapidly accelerate CO clearance and improve outcomes for survivors of acute CO poisoning.

Prediction of troponin I and N-terminal pro-brain natriuretic peptide levels in acute carbon monoxide poisoning using advanced electrocardiogram analysis, Alexandria, Egypt

The study aimed at assessing the diagnostic ability of advanced electrocardiogram (ECG) analysis to predict the levels of NT-proBNP and Troponin I. ECG and the blood NT-proBNP and Troponin I were taken from 50 acutely carbon monoxide poisoned patients and 21 control subjects matched with age and sex. The severity of the studied cases was classified into mild, moderate, and severe using clinical classification. ECG parameters (RR interval, corrected QT (QTc) interval, P wave dispersion (Pwd)), and cardiac biomarkers (NT-proBNP and Troponin I) were significantly higher in cases than in control (p= 0.015, 0.008, 0.002, <0.001, and <0.001 respectively). Cut-off values resulted from combined ROC curves analysis can predict blood Troponin I more than 0.05 ng/ml and NT-proBNP more than 125 pg/ ml (with 88% and 84% accuracy respectively). In addition, two regression equations were developed using all studied ECG parameters to predict Troponin I and NT-proBNP (with 68% and 43% accuracy respectively). RR average, PR average, QRS average, QTd, QTc, and Pwd could be used to predict Troponin I and NT-proBNP levels with good accuracy in carbon monoxide poisoning patients.

Diagnostic performance and optimal cut-off values of cardiac biomarkers for predicting cardiac injury in carbon monoxide poisoning

OBJECTIVE

This study aimed to compare the diagnostic performance of cardiac biomarkers and to evaluate the optimal cut-off values for echocardiographic cardiac injury prediction in patients with carbon monoxide (CO) poisoning.

METHODS

This retrospective observational cohort study included adult patients with acute CO poisoning. Patients who did not undergo transthoracic echocardiography, which was used to define patients with cardiac injury (ejection fraction <55%), were excluded. The area under the curve was used to evaluate diagnostic performance for cardiac injury prediction. Mann-Whitney U, chi-square, and Fisher exact tests were used to analyze data.

RESULTS

After excluding the 27 patients who did not undergo echocardiography, 114 patients were included in the study. Fifteen (13.2%) patients had cardiac injury. The area under the curve values for the B-type natriuretic peptide, creatine kinase-myocardial band, and troponin I were 0.711 (95% confidence interval [CI], 0.527-0.895; P=0.011), 0.766 (95% CI, 0.607-0.926; P=0.001), and 0.801 (95% CI, 0.647-0.955; P<0.001), respectively, with optimal cut-off values of 330 pg/mL, 10.1 ng/mL, and 0.455 ng/mL, respectively. The sensitivity, specificity, and positive and negative predictive values of troponin I were 67%, 91%, 53%, and 95%, respectively.

CONCLUSION

Troponin I showed the best diagnostic performance for predicting cardiac injury in patients with CO poisoning. A cut-off value of 0.455 ng/mL appeared optimal for cardiac injury prediction. However, further studies on cardiac biomarkers and other diagnostic tools in CO poisoning are needed given the low sensitivity of troponin I.

WITHDRAWN: "Hyperbaric oxygen treatment resistant carbon monoxide poisoning" [JCA 55 (2019) 102-102]

The Publisher regrets that this article is an accidental duplication of an article that has already been published in Abbreviated Journal Title, volume (year) first page - last page, http://dx.doi.org/10.1016/j.jclinane.2018.06.035. The duplicate article has therefore been withdrawn. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/our-business/policies/article-withdrawal

Impact of Hyperbaric Oxygen Therapy on Subsequent Neurological Sequelae Following Carbon Monoxide Poisoning

The purpose of this study was to evaluate the effects of hyperbaric oxygen therapy (HBOT) on reducing neurological sequelae (NS) in patients with carbon monoxide poisoning (COP). Using a nationwide database of insurance claims in Taiwan, we conducted a population-based cohort study to identify 24,046 patients with COP diagnosed between 1999 and 2012, including 6793 (28.2%) patients who received HBOT and 17,253 (71.8%) patients who did not. We followed the two cohorts of patients and compared the occurrence of NS. The two cohorts had similar sex ratios, but patients who received HBOT were younger (34.8 ± 14.8 vs. 36.1 ± 17.2 years, p < 0.001). Patients who received HBOT had a higher risk for NS (adjusted hazard ratio [AHR]: 1.4; 95% confidence interval [CI]: 1.4⁻1.5), after adjusting for age, sex, underlying comorbidities (hypertension, diabetes, chronic obstructive pulmonary disease, hyperlipidemia, malignancy, coronary artery disease, congestive heart failure, liver disease, renal disease, connective tissue disease, human immunodeficiency virus [HIV] infection, and alcoholism), monthly income, suicide, drug poisoning, and acute respiratory failure. We observed similar findings when we stratified the patients by age, sex, underlying comorbidities, and monthly income. The increased risk was most prominent in the first 2 weeks (AHR: 2.4; 95% CI: 2.1⁻2.7) and remained significant up to 6 months later (AHR: 1.6; 95% CI: 1.4⁻1.7). The risk for NS was higher in patients with COP who received HBOT than in those who did not, even after considering the possible impact of longer observation periods on survivors. Further studies that included the potential confounding factors we did not measure are needed to confirm findings in this study.