Predicting of neuropsychosis in carbon monoxide poisoning according to the plasma troponin, COHb, RDW and MPV levels: Neuropsychoses in carbon monoxide poisoning

Red blood cell distribution width (RDW) reflects disease severity in patients with carbon monoxide poisoning: systematic literature review and meta-analysis

No definitive prognostic biomarkers for carbon monoxide (CO) poisoning have been proposed. The aim of this study is to investigate, through a systematic literature review and pooled analysis, whether red blood cell distribution width (RDW) can predict disease severity in CO-poisoned patients. We performed an electronic search in Scopus and PubMed using the keywords: 'red blood cell distribution width' OR 'RDW' AND 'carbon monoxide' AND 'poisoning,' with no time or language restrictions (i.e. through August 2023) to find clinical studies that examined the value of RDW in patients with varying severity of CO poisoning. The analysis was performed according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) 2020 reporting checklist. We identified 29 articles, seven of which were included in our analysis, with a total of 1979 CO-poisoned patients, 25.9% of whom were severely ill. In all but one of the studies, the RWD mean or median value was higher in CO-poisoned patients with severe disease. The weighted mean difference (WMD) of RDW was 0.36 (95% confidence interval (CI), 0.26-0.47)%. In the three articles in which the severity of illness in CO-poisoned patients was defined as cardiac injury, the WMD of the RDW was 1.26 (95%CI, 1.02-1.50)%. These results suggest that monitoring RDW in CO-poisoned patients may help to determine the severity of disease, particularly cardiac injury.

Predicting acute brain lesions on magnetic resonance imaging in acute carbon monoxide poisoning: a multicenter prospective observational study

An acute brain lesion (ABL) identified by brain magnetic resonance imaging (MRI) after acute carbon monoxide (CO) poisoning is a strong prognostic factor for the development of delayed neuropsychiatric syndrome (DNS). This study aimed to identify predictors of ABLs on MRI in patients with acute CO poisoning. This was a multicenter prospective registry-based observational study conducted at two tertiary hospitals. A total of 1,034 patients were included. Multivariable logistic regression analysis showed that loss of consciousness (LOC) (adjusted odds ratio [aOR] 2.68, 95% Confidence Interval [CI]: 1.49-5.06), Glasgow Coma Scale (GCS) score < 9 (aOR 2.41, 95% CI: 1.49-3.91), troponin-I (TnI) (aOR 1.22, 95% CI: 1.08-1.41), CO exposure duration (aOR 1.09, 95% CI: 1.05-1.13), and white blood cell (WBC) (aOR 1.05, 95% CI: 1.01-1.09) were independent predictors of ABLs on MRI. LOC, GCS score, TnI, CO exposure duration, and WBC count can be useful predictors of ABLs on MRI in patients with acute CO poisoning, helping clinicians decide the need for an MRI scan or transfer the patient to an appropriate institution for MRI or hyperbaric oxygen therapy.

Carbon monoxide poisoning: Diagnosis and management

ABSTRACT

Diagnosis of carbon monoxide (CO) poisoning is challenging, as it is generally based on a history of present illness leading to clinical suspicion. CO is a tasteless, odorless, and colorless gas that has become known as the "silent killer." CO poisoning affects approximately 50,000 people in the United States each year and presents with wide range of nonspecific symptoms. Patients often do not know that they are being exposed to CO gas; it is therefore important to ask pertinent questions when taking a patient's history. Treatment consists of oxygen therapy. If a diagnosis is not made and treatment is not administered promptly, complications may occur.

Association of carbon monoxide poisonings and carboxyhemoglobin levels with COVID-19 and clinical severity

BACKGROUND

Coronavirus disease 2019 (COVID-19), which recently spread throughout the entire world, is still a significant health issue. Additionally, the most common cause of risky poisoning in emergency services is carbon monoxide (CO) poisoning. Both disorders seem to merit more research as they have an impact on all bodily systems via the lungs.

AIM

To determine how arterial blood gas and carboxyhemoglobin (COHb) levels affect the clinical and prognostic results of individuals requiring emergency treatment who have both COVID-19 and CO poisoning.

METHODS

Between January 2018 and December 2021, 479 CO-poisoning patients participated in this single-center, retrospective study. Patients were primarily divided into two groups for analysis: Pre-pandemic and pandemic periods. Additionally, the pandemic era was divided into categories based on the presence of COVID-19 and, if present, the clinical severity of the infection. The hospital information system was used to extract patient demographic, clinical, arterial blood gas, COVID-19 polymerase chain reaction, and other laboratory data.

RESULTS

The mean age of the 479 patients was 54.93 ± 11.51 years, and 187 (39%) were female. 226 (47%) patients were in the pandemic group and 143 (30%) of them had a history of COVID-19. While the mean potential of hydrogen (pH) in arterial blood gas of all patients was 7.28 ± 0.15, it was 7.35 ± 0.10 in the pre-pandemic group and 7.05 ± 0.16 in the severe group during the pandemic period (P < 0.001). COHb was 23.98 ± 4.19% in the outpatients and 45.26% ± 3.19% in the mortality group (P < 0.001). Partial arterial oxygen pressure (PaO2) was 89.63 ± 7.62 mmHg in the pre-pandemic group, and 79.50 ± 7.18 mmHg in the severe group during the pandemic period (P < 0.001). Despite the fact that mortality occurred in 35 (7%) of all cases, pandemic cases accounted for 30 of these deaths (85.7%) (P <0.001). The association between COHb, troponin, lactate, partial arterial pressure of carbon dioxide, HCO3, calcium, glucose, age, pH, PaO2, potassium, sodium, and base excess levels in the pre-pandemic and pandemic groups was statistically significant in univariate linear analysis.

CONCLUSION

Air exchange barrier disruption caused by COVID-19 may have pulmonary consequences. In patients with a history of pandemic COVID-19, clinical results and survival are considerably unfavorable in cases of CO poisoning.

Clinical and Laboratory Characteristics Predicting the Severity of Carbon Monoxide Poisoning in Children: A Single-Center Retrospective Study

OBJECTIVES

Carbon monoxide poisoning (COP) is extremely common throughout the world. The purpose of this study was to assess the demographic, clinical, and laboratory characteristics predicting the severity COP in children.

METHODS

The study included 380 children diagnosed with COP between January 2017 and January 2021 and 380 healthy controls. Carbon monoxide poisoning was diagnosed based on the medical history and a carboxyhemoglobin (COHb) level of more than 5%. The patients were classified as mild (COHb 10%), moderate (COHb 10%-25%), or severely (COHb > 25%) poisoned.

RESULTS

The mean age of the severe group was 8.60 ± 6.30, for the moderate group was 9.50 ± 5.81, for the mild group was 8.79 ± 5.94, and for the control group was 8.95 ± 5.98. The most common place of exposure was at home and all cases were affected accidentally. The coal stove was the most common source of exposure, followed by natural gas. The most common symptoms were nausea/vomiting, vertigo, and headache. Neurologic symptoms such as syncope, confusion, dyspnea, and seizures were more common in the severe group. A total of 91.3% of the children had hyperbaric oxygen therapy, 3.8% were intubated, and 3.8% were transferred to intensive care in the severe group, whereas no death or sequela was observed. Mean platelet volume and red cell distribution width had the highest area under the curve in the receiver operating characteristic analysis (0.659; 0.379). A positive and low statistically significant relationship was found between COHb levels and troponin and lactate levels in the severe group ( P < 0.05).

CONCLUSIONS

Carbon monoxide poisoning progressed more severely in children presented with neurological symptoms and have elevated red cell distribution width and mean platelet volume. Even in severe COP cases, satisfactory results have been obtained with early and appropriate treatment.

The Value of Neutrophil:Lymphocyte Ratio and Platelet:Lymphocyte Ratio in Predicting Clinical Severity in Children with Carbon Monoxide Poisoning

OBJECTIVE

To compare the values of neutrophil:lymphocyte ratio (NLR), platelet:lymphocyte ratio (PLR), and mean platelet volume (MPV) with carboxyhemoglobin (COHb) and lactate levels in children with acute CO intoxication.

METHODS

In this retrospective study, the patients were divided into two groups: mild-to-moderate carbon monoxide poisoning (COP) (COHb 10%-20%) and severe COP (COHb > 20%) according to the COHb levels in the application. All patients were compared in terms of NLR, PLR, and MPV parameters according to the severity of poisoning and the high lactate levels (≥ 2.2 mmol/L).

RESULTS

A total of 261 children with COP were included in the study. The number of patients with mild-to-moderate COP was 183 (70.1%), and the number of patients with severe COP was 78 (29.9%). NLR [2.57 (3.27), 1.65 (1.93), (p = 0.001)] and PLR [123.0 (88.24), 92.8 (54.1), (p = 0.001)] values of mild-to-moderate COP were statistically significantly lower than the severe COP group. In the group with high lactate level, PLR values were significantly lower [120.1 (71.9), 100.2 (85.4), (p = 0.017)]. NLR and PLR values were found to be predictive of severe COP.

CONCLUSION

NLR and PLR can be used for detection of clinical severity in patients with COP. PLR can be used in conjunction with lactate levels to detect tissue-level exposure in patients with COP.

Usefulness of a modified poisoning severity score for predicting prognosis in acute carbon monoxide poisoning

INTRODUCTION

The poisoning severity score (PSS) was developed to grade the severity of various types of poisoning. However, in its current form, it requires investigating many variables, some of which have been found not to be associated with carbon monoxide (CO) poisoning severity. Therefore, in this study, we modified the PSS for CO poisoning and compared its usefulness to that of the original PSS, as an early prognostic factor of short-term outcome in CO poisoning patients.

METHODS

This was a retrospective observational study conducted in patients with CO poisoning who visited the emergency department between January 2014 and December 2020. Patients' primary outcome was their Cerebral Performance Category (CPC) scale score at discharge, which classified those with CPC 1-2 as having a favorable outcome and those with CPC 3-5 as having a poor outcome. We calculated the patients' PSS and their CO-modified PSS by replacing blood and metabolic balance category in the original PSS with carboxyhemoglobin (COHb) and lactate levels, respectively.

RESULTS

This study included 891 patients, of which 852 (95.6%) and 39 (4.4%) were classified into the favorable and poor outcome groups, respectively. Using multivariate analysis, the PSS (odds ratio [OR], 22.961; 95% confidence interval [CI], 10.641-49.546; p < 0.001) and CO-modified PSS (OR, 28.856; 95% CI, 12.874-64.679; p < 0.001) were both found to be associated with poor outcomes at hospital discharge. The areas under the receiver operating characteristic curves for the PSS and CO-modified PSS were 0.874 (95% CI, 0.850-0.895) and 0.881 (95% CI, 0.858-0.901), respectively.

CONCLUSION

The CO-modified PSS, with fewer variables than the original PSS, was not inferior to predict poor outcomes, and if COHb level is considered together with other parameters, then it can be used both for predicting prognosis and in diagnosis.

The prognostic value of red cell distribution width for in-hospital mortality in patients with methanol poisoning

AIM

Red blood cell distribution width (RDW) is a numerical measure of variability in the size of circulating erythrocytes and is routinely reported as a component of a complete blood count panel. It has been shown that higher RDW is associated with increased mortality and morbidity in several types of intoxication. This study was designed to evaluate the prognostic value of RDW for in-hospital mortality and need of invasive mechanical ventilation in patients with methanol poisoning.

METHODS

A retrospective chart review of patients with methanol poisoning was performed using data from Adana City Training and Research Hospital obtained between January 2019 and January 2020. Patients' demographics, clinical features, the time elapsed between ingestion and presentation, the treatment applied, blood gas analysis, laboratory measures including RDW on admission, and clinical outcome were obtained.

RESULTS

A total of 42 patients with methanol poisoning were included in the study with a mean age of 45 ± 11 years. The overall mortality was 21.4%. Values of RDW on admission were significantly higher in non-survivors than in survivors. The area under the receiver operating curve of RDW was 0.778 (95% CI: 0.567-0.988) for predicting in-hospital mortality and 0.762 (95% CI: 0.592-0.932) for predicting mechanical ventilator requirement.

CONCLUSION

This study suggests that increased RDW on the first admission is associated with mortality and with mechanical ventilator requirement in patients with methanol poisoning.

Clinical predictors of delayed neurological sequelae in charcoal-burning carbon monoxide poisoning

BACKGROUND

The main objective of the treatment of acute carbon monoxide (CO) poisoning is to prevent delayed neurological sequelae (DNS). However, today there is still no objective screening tool to identify patients at high risk of developing DNS. The aim of this study was to identify clinical factors that could predict DNS after acute charcoal-burning CO poisoning.

METHODS

This prospective observational study was conducted from September 1, 2019 to August 31, 2020 in a single academic medical center. Patients older than 18 years of age suffering from charcoal-burning CO poisoning were included in the study. After acute recovery, patients were followed up for six weeks to investigate for DNS development. The clinical predictors of DNS were determined using a multivariate logistic regression model.

RESULTS

Of the 217 patients-113 males (52.1%), median age 37.0 (27.5-51.5) years-included, 49 (22.6%) developed DNS. The multivariate logistic regression analysis revealed the independent predictors of DNS as a lower initial Glasgow Coma Scale (GCS) score (adjusted odds ratio (AOR): 0.73, 95% confidence interval (CI): 0.62-0.87), a longer duration of CO exposure (AOR: 2.18, 95% CI: 1.65-2.88), and the presence of acute brain lesions with high signal intensity on diffusion-weighted imaging (AOR: 5.22, 95% CI: 1.50-18.08). The created multivariate regression model predicted DNS development with high accuracy (area under the curve: 0.93, 95% CI: 0.89-0.97).

CONCLUSION

A low initial GCS score, longer exposure to CO and abnormal findings on diffusion-weighted magnetic resonance imaging can assist in the early identification of patients at high risk of DNS development.

The predictive value of neutrophil-lymphocyte ratio at presentation for delayed neurological sequelae in carbon monoxide poisoning

OBJECTIVE

To explore the predictive value of neutrophil-lymphocyte ratio (NLR) at presentation for delayed neurological sequelae (DNS) in carbon monoxide (CO) poisoning.

METHODS

This single-center retrospective observational study included a total of 253 consecutive patients who visited the emergency department (ED) due to acute CO intoxication between 7 October 2015 and 31 December 2019. The included patients had a history of coma and their blood routine was measured within one hour of ED admission. They were divided into two groups according to the presence of DNS, including those who developed DNS (DNS group) and those who did not (non-DNS group).

RESULTS

A total of 171 patients were included in this research, and 49 (28.7%) developed DNS. The median NLR at ED admission was obviously higher in the DNS group (10.60 [9.69-15.34]) than in the non-DNS group (7.53 [5.86-8.56]) (p < 0.001). Multivariate analysis indicated that a high NLR (adjusted odds ratio (AOR): 1.78, 95% confidence interval (CI): 1.46-2.18) and the occurrence of acute brain lesions (AOR: 7.50, 95%CI: 2.86-19.68) on diffusion-weighted imaging were independent predictors of DNS. The NLR was more than 8.97. The prediction of occurrence of DNS had a sensitivity of 93.88% and a specificity of 84.43%. Kappa value was 0.713. The predicted results showed good authenticity and consistency.

CONCLUSION

The level of NLR at presentation had good predictive value for the development of DNS, showing the superior value for clinical application.