Risk Factors and Outcome Analysis in Children with Carbon Monoxide Poisoning

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.

Practical Recommendations for the Evaluation and Management of Cardiac Injury Due to Carbon Monoxide Poisoning

Carbon monoxide (CO) is a relatively frequent cause of poisoning evaluated in emergency departments. The risk of neurologic injuries, such as cognitive, psychological, vestibular, and motor deficits, is 25% to 50%. However, the risk of cardiac injuries should also be considered. Among patients with CO poisoning, the mortality in patients with myocardial injury is approximately 3 times greater than that in patients without myocardial injury. In large-scale studies, up to 69.2% of patients with acute CO poisoning exhibiting elevated troponin I levels and no underlying cardiovascular illnesses had late gadolinium enhancement on cardiac magnetic resonance, suggesting covert CO-induced myocardial fibrosis. Myocardial damage can be evaluated using electrocardiography, echocardiography, computed tomography, and cardiac magnetic resonance. This paper offers recommendations for cardiac evaluations based on our collective experience of managing >2,000 cases of acute CO poisoning with supporting information taken from peer-reviewed published reports on CO poisoning.

Diagnostic challenge in a 2-year-old boy poisoned with carbon monoxide: A case report

Key Clinical Message

Carbon monoxide poisoning diagnosis is sometimes very difficult and should be considered in the differential diagnosis list of children's consciousness disorders even in summer.

Abstract

Carbon monoxide poisoning is very dangerous, and sometimes, it is difficult to diagnose. Especially, this poisoning may have non-specific manifestations in children and can be confused with other diseases. Here we present a 2-year-old child who suffered a disturbance of consciousness during the summer season. He and his family were travelers who had come to Mashhad from Kerman and were staying in a hotel room, after various investigations. It has been found that he was poisoned with carbon monoxide gas due to the leakage of carbon monoxide gas from the chimney pipe of the engine room related to the hotel's water heating into the room. After receiving oxygen and supportive treatments, he recovered and was discharged with good health. Poisoning with carbon monoxide gas is very dangerous, and the awareness of health and medical personnel in this field is essential.

Assessment of Paediatric Forensic Cases Under the Age of 18 Who Presented to the Emergency Clinic: The Case of Kilis, a Border City with Syria

AIM

This study was conducted to determine the paediatric forensic cases under the age of 18 from of the year of the outbreak of war.

DESING AND METHODS

The population of the study included 16,970 people under the age of 18, who were accepted as forensic cases among 88,052 cases, who presented to the emergency department of Kilis State Hospital between January 2011 and November 2019. The application time of the patients, their nationality, age, gender, their types of application to the emergency department, the event causing the forensic case, and the follow-up and treatment methods in the emergency department were recorded on the standard data entry form.

RESULTS

Among all the paediatric forensic cases, it was determined that 52.0% were Syrian, 70.8% were boys, 30.0% were in the age range of 11 and 15 years and 20.5% had an outpatient treatment.

CONCLUSIONS

In this study, although juvenile forensic rates are consistent with the literature, the higher forensic cases of Syrian nationality was determined as a striking result.

PRACTICE IMPLICATIONS

Today, considering extraordinary situations such as wars and armed conflicts, more refugees may benefit from Turkish healthcare services in the in the forthcoming periods and it is important for community health to conduct studies in this field.

The effect of full blood count and cardiac biomarkers on prognosis in carbon monoxide poisoning in children

AIMS

In this study, cardiac biomarkers, blood parameters, electrocardiography (ECG), and echocardiography were investigated in children with carbon monoxide (CO) poisoning, and the diagnostic value of these parameters was investigated.

METHODS

The demographical, clinical, and laboratory data of children aged 0-18 years who were admitted to the pediatric emergency department due to CO poisoning between January 2019 and January 2022 were retrospectively scanned from medical records. The patients were divided into two groups as troponin-I positive and troponin-I negative.

RESULTS

There were 107 children aged 0-18 years (average age, 10.46 ± 5.77 years; 51% female) with CO poisoning. There were 13 patients with troponin-I positive myocardial injury. Troponin-I was positive in 3 patients whose carboxyhemoglobin (COHb) level was below 2% at the time of admission. In one patient, troponin-I, which was normal at admission, increased by the 24th hour of hospitalization. Hyperbaric oxygen therapy was given due to headache in one patient, although the COHb level of that patient was below 25%. An NT-proBNP level of ≥ 219.5 ng/L predicted the development of troponin-I positivity with a sensitivity of 70% and a specificity of 86.7% (AUC, 0.967 (0.58-0.994); p = 0.017). White blood cell (WBC), neutrophil, neutrophil-to-lymphocyte ratio (NLR), immature granulocyte (IG), and IG% levels were found to be significantly higher in the troponin-positive patient group. DISCUSSION AND CONCLUSION: NT-proBNP has been shown to be an early diagnostic marker for myocardial dysfunction. Additionally, when cardiac markers are not available, full blood parameters may assist clinicians for patient treatment and referral.

[Carbon monoxide intoxication-New aspects and current guideline-based recommendations]

Carbon monoxide poisoning is a common and potentially life-threatening intoxication, showing an interindividual variety of unspecific symptoms as well as late neurological and other sequelae. Two new German guidelines (S2k guidelines diagnosis and treatment of carbon monoxide poisoning as well as S3 guidelines oxygen therapy in the acute care of adult patients) focus on current evidence-based information on diagnostics as well as therapeutic options with considerable uncertainty remaining. This review summarizes current information and presents a flow scheme for daily practical use.

Long Short Term Memory Neural Network-Based Model Construction and Fne-Tuning for Air Quality Parameters Prediction

Air pollution has increased worries regarding health and ecosystems. Precise prediction of air quality parameters can assist in the effective action of air pollution control and prevention. In this work, a deep learning framework is proposed to predict parameters such as fine particulate matter and carbon monoxide. Long Short Term Memory (LSTM) neural network-based model that processes sequences in forward and backward direction to consider the influence of timesteps in both directions is employed. For further learning, unidirectional layers’ stacking is implemented. The performance of the model is optimized by fine-tuning hyperparameters, regularization techniques for overfitting resolution, and various merging options for the bidirectional input layer. The proposed model achieves good optimization and performs better than the simple LSTM and a Recurrent Neural Network (RNN) based model. Moreover, an attention-based mechanism is adopted to focus on more significant timesteps for prediction. The self-attention approach improves performance further and works well especially for longer sequences and extended time horizons. Experiments are conducted using real-world data collected, and results are evaluated using the mean square error loss function.

Delayed Neuropsychiatric Sequel Following Pediatric Carbon Monoxide Poisoning: A Case Report and Literature Review

Carbon monoxide (CO) poisoning is a serious health problem. The main pathophysiological mechanism of acute CO poisoning is hypoxia due to the formation of carboxyhemoglobin (COHb). Delayed neuropsychiatric sequel (DNPS) occurs following an interval of several days to several weeks post-CO exposure and can present in many different manifestations, ranging from behavioral and mood disorders to encephalopathy and seizures and cause long-term neuropsychiatric sequel. The pathogenesis of DNPS following CO poisoning is a complex one that encompasses hypoxia-induced encephalopathy as well as inflammation, direct cellular changes and damage. The incidence varies and treatment is debated. We display a case of a previously healthy 13-year-old boy suffering from DNPS, presenting with seizures and encephalopathy and later developing optic nerve damage. Increased awareness to this condition might help diagnose future patients and aid in the understanding of the pathogenesis and treatment options for this poorly understood condition.

S2k guideline diagnosis and treatment of carbon monoxide poisoning

Carbon monoxide (CO) can occur in numerous situations and ambient conditions, such as fire smoke, indoor fireplaces, silos containing large quantities of wood pellets, engine exhaust fumes, and when using hookahs. Symptoms of CO poisoning are nonspecific and can range from dizziness, headache, and angina pectoris to unconsciousness and death. This guideline presents the current state of knowledge and national recommendations on the diagnosis and treatment of patients with CO poisoning. The diagnosis of CO poisoning is based on clinical symptoms and proven or probable exposure to CO. Negative carboxyhemoglobin (COHb) levels should not rule out CO poisoning if the history and symptoms are consistent with this phenomenon. Reduced oxygen-carrying capacity, impairment of the cellular respiratory chain, and immunomodulatory processes may result in myocardial and central nervous tissue damage even after a reduction in COHb. If CO poisoning is suspected, 100% oxygen breathing should be immediately initiated in the prehospital setting. Clinical symptoms do not correlate with COHb elimination from the blood; therefore, COHb monitoring alone is unsuitable for treatment management. Especially in the absence of improvement despite treatment, a reevaluation for other possible differential diagnoses ought to be performed. Evidence regarding the benefit of hyperbaric oxygen therapy (HBOT) is scant and the subject of controversy due to the heterogeneity of studies. If required, HBOT should be initiated within 6 h. All patients with CO poisoning should be informed about the risk of delayed neurological sequelae (DNS).

Neurocognitive sequelae after carbon monoxide poisoning and hyperbaric oxygen therapy

Carbon monoxide (CO) has been the leading cause of poisoning mortality in many countries and hyperbaric oxygen (HBO) is a widely accepted treatment for CO poisoning. However, some patients with CO poisoning will still develop neurocognitive sequelae regardless of HBO therapy, which can persist since CO poisoning or be present days to weeks after a recovery from CO poisoning. HBO has been used in the prevention and treatment of neurocognitive sequelae after CO poisoning, and some mechanisms are also proposed for the potential neuroprotective effects of HBO on the neurocognitive impairment after CO poisoning, but there is still controversy on the effectiveness of HBO on neurocognitive sequelae after CO poisoning. In this paper, we briefly introduce the neurocognitive sequelae after CO poisoning, summarize the potential predictive factors of neurocognitive sequelae, and discuss the use of HBO in the treatment and prevention of neurocognitive sequelae after CO poisoning.

Delayed Neurological Sequelae in an Infant after Carbon Monoxide Intoxication

Delayed neurological sequelae are symptoms that appear over a period of time after an acute event of carbon monoxide poisoning. The incidence of delayed neurological sequelae is lower in children than in adults and is even more uncommon in infants. Here, we present a case of a 4-month-old infant who developed delayed neurological sequelae after carbon monoxide intoxication. She presented with neurologic symptoms, including opisthotonus, athetoid movements, anterior tongue thrust, and opsoclonus. Because these symptoms are starkly different from those of adults, they should be compared with age-appropriate developmental milestones. Because of their faster metabolic rate and presence of fetal hemoglobin, infants with developing brains may be especially vulnerable to carbon monoxide toxicity. Therefore, thorough neurologic examination and prompt treatment are critical for infants who experience carbon monoxide intoxication.

The occurrence of delayed neuropsychologic sequelae in acute carbon monoxide poisoning patients after treatment with hyperbaric or normobaric oxygen therapy

This study aimed at assessing which one of the 2 therapies is better for treating carbon monoxide (CO) poisoning from the perspective of reducing delayed neuropsychologic sequelae (DNS).We used Taiwan's National Health Insurance Research Database (NHIRD) to conduct a nationwide population-based cohort study to assess which therapy is better for CO poisoning patients. To accurately identify patients with DNS, the definition of DNS is included neurological sequelae, and cognitive and psychological sequele. The independent variable was therapy and the dependent variable was DNS occurred within 1 year after discharge from a medical institution. The control variables were age, gender, the severity of CO poisoning, and comorbidities present before CO poisoning admission.The risk of developing DNS in patients treated with Hyperbaric Oxygen (HBO) was 1.87-fold (P < .001) than normobaric oxygen (NBO) therapy. The severity of CO poisoning and comorbidities were also found to have significant influences on the risk of developing DNS.HBO may be a risk therapy for treating CO poisoning.

Unreliable Early Neuroprognostication After Severe Carbon Monoxide Poisoning Is Likely Due to Cytopathic Hypoxia: A Case Report and Discussion

A 17-year-old girl was found unconscious in a running vehicle. She developed very severe acute respiratory distress syndrome (which was treated with rescue high-frequency oscillation), hemodynamic instability, acute kidney injury, rhabdomyolysis, and remained comatose with a Glasgow Coma Scale score of 3 and gasping respirations for 67 hours (when the Glasgow Coma Scale score improved to 6, with tachypnea to Paco ₂ 28 and pH 7.5). By 92 hours, she was obeying commands, and she was extubated at 96 hours, shortly after which she was conversing with family and texting on her phone. A magnetic resonance imaging (MRI) scan 6 days after being found showed subacute infarctions affecting the medial aspect of the globus pallidus bilaterally as well as a small cortical/subcortical infarction in the right parietal lobe. At a 7-week follow-up, she had no delayed-onset signs of brain injury. This case demonstrated that neurologic prognostication after carbon monoxide poisoning may be unreliable for more than 72 hours after injury. We discuss that it is possible that the mitochondrial dysfunction induced by carbon monoxide was responsible for a functional coma without irreversible brain injury, similar to the mechanism of cytopathic hypoxia in multiple-organ dysfunction that allows some other organ recovery without necrosis in survivors.

The Diagnosis and Treatment of Carbon Monoxide Poisoning

BACKGROUND

The symptoms of carbon monoxide (CO) poisoning are nonspecific, ranging from dizziness and headache to unconsciousness and death. A German national guideline on the diagnosis and treatment of this condition is lacking at present.

METHODS

This review is based on a selective literature search in the PubMed and Cochrane databases, as well as on existing guidelines from abroad and expert recommendations on diagnosis and treatment.

RESULTS

The initiation of 100% oxygen breathing as early as possible is the most important treatment for carbon monoxide poisoning. In case of CO poisoning, the reduced oxygen-carrying capacity of the blood, impairment of the cellular respiratory chain, and immune-modulating processes can lead to tissue injury in the myocardium and brain even after lowering of the carboxyhemoglobin (COHb) concentration. In patients with severe carbon monoxide poisoning, an ECG should be obtained and biomarkers for cardiac ischemia should be measured. Hyperbaric oxygen therapy (HBOT) should be critically considered and initiated within six hours in patients with neurologic deficits, unconsciousness, cardiac ischemia, pregnancy, and/or a very high COHb concentration. At present, there is no general recommendation for HBOT, in view of the heterogeneous state of the evidence from multiple trials. Therapeutic decision-making is directed toward the avoidance of sequelae such as cognitive dysfunction and cardiac complications, and the reduction of mortality. Smoke intoxication must be considered in the differential diagnosis. The state of the evidence on the diagnosis and treatment of this condition is not entirely clear. Alternative or supplementary pharmacological treatments now exist only on an experimental basis.

CONCLUSION

High-quality, prospective, randomized trials that would enable a definitive judgment of the efficacy of HBOT are currently lacking.

Analysis of the effects of COHb, lactate, and troponin levels on the clinical process and outcome in patients who were admitted to the emergency service due to carbon monoxide poisoning

OBJECTIVE

The aim of the present study was to determine the demographic, medical, and treatment characteristics of patients followed up with the diagnosis of carbon monoxide (CO) poisoning in emergency care and also to determine the relationship of these patients' clinical process and outcome between carboxyhemoglobin (COHb), lactate, and troponin levels.

METHODS

The present study was conducted retrospectively between 01/01/2013 and 01/01/2016 by examining 450 patients who were referred to the emergency service for CO poisoning. The ages; sexualities; manners of application; clinical findings; levels of blood COHb, lactate, and troponin; applied oxygen treatment method; and outcome of patients were evaluated. Data analysis was done by Shapiro-Wilk, Student's t, Mann-Whitney U, and chi-square tests.

RESULTS

A total of 450 patients were included in the study. The median age of the patients was 35 (interquartile range (IQR) 26.75-45.00) years. In the study where data are not homogeneously distributed, the median levels of COHb, lactate, and troponin were 11.80% (IQR 3-23), 1.60 (IQR 1.10-2.5) mmol/l, and 0.00 (IQR 0.000-0.003) ng/ml, respectively. The levels of lactate were detected to be statistically high in patients who had syncope and who received hyperbaric oxygen treatment (p<0.05). In addition, the levels of lactate and troponin were significantly higher in patients who were hospitalized (p<0.05).

CONCLUSION

The levels of COHb, lactate, and troponin can provide an insight to the clinician about hospitalization and the type of treatment.

Hyperbaric oxygenation in pediatrics: indications in the light of evidence - based medicine

Hyperbaric oxygen therapy (HBOT), which is a centuries-old treatment, has now increasingly often been used in the pediatric population. The basic indications for HBOT are well-known disease entities, i.e. carbon monoxide poisoning or decompression sickness. Due to the immunomodulatory properties of hyperbaric oxygen, attempts are made to use HBOT in the treatment of atopic dermatitis or inflammatory bowel diseases. The close cooperation between pediatricians and hyperbaric medicine teams is very important to obtain optimal results. The aim of this article is to present the mechanism of hyperbaric oxygen activity, and its influence on selected disease entities. The paper outlines new perspectives for HBOT in the pediatric population.

Predictive Role of QTc Prolongation in Carbon Monoxide Poisoning-Related Delayed Neuropsychiatric Sequelae

Objective

Delayed neuropsychiatric sequelae (DNS) are serious complications of carbon monoxide (CO) poisoning that adversely affect poisoned patients' quality of life as well as socioeconomic status. This study aimed to determine clinical predictors of DNS in patients with CO poisoning.

Methods

This retrospective study included all CO-poisoned patients admitted to the emergency department (ED) of Linkou Chang Gung Memorial Hospital in Taiwan from 1 January 2009 to 31 December 2015. The medical records of all patients with CO poisoning were carefully reviewed, and relevant data were abstracted into a standardised form. Univariate and multivariate logistic regression models were used to identify predictors of DNS after CO poisoning. Receiver operating characteristic (ROC) curve analysis was used to determine the ideal cut-off value for continuous variables that predict the development of DNS.

Results

A total of 760 patients with CO poisoning were identified during the study period. Among them, 466 were eligible for the analysis of predictors of DNS. In multivariate analysis, Glasgow Coma Scale <9 (odds ratio [OR], 2.74; 95% confidence interval [CI], 1.21-6.21), transient loss of consciousness (OR, 3.59; 95% CI, 1.31-9.79), longer duration from CO exposure to ED presentation (OR, 1.05; 95% CI, 1.03-1.08), and corrected QT (QTc) prolongation (OR, 2.61; 95% CI, 1.21-5.61) were found to be associated with a higher risk of DNS. The area under the ROC curve (AUC) for QTc interval measured within 6 h after exposure best predicted the development of DNS, with a result of 0.729 (95% CI 0.660-0.791). Moreover, the best cut-off value of the QTc interval was 471 ms, with a sensitivity of 53.3% and a specificity of 85.1%.

Conclusions

We identified several potential predictors of DNS following CO poisoning. Among them, QTc prolongation found within 6 h after exposure is a novel predictor of DNS, which may be helpful in the future care of patients with CO poisoning.

Fatal carbon monoxide poisoning: A lesson from a retrospective study at All India Institute of Medical Sciences, New Delhi

Background:

Carbon monoxide (CO) is a colorless, odorless, tasteless, and nonirritating gas which makes it difficult for those who are exposed, to detect it, leading to unexpected death. This study was undertaken to see the pattern of fatal CO poisoning and to discuss preventive aspect.

Materials and Methods:

It was a retrospective descriptive study of fatal CO cases which were autopsied at All India Institute of Medical Sciences, New Delhi, from the year 2010 to the year 2015. The cases were analyzed as per age groups, circumstances of death, season of death, and sources of CO formation.

Results and Discussion:

The study involved 40 cases of fatal CO poisoning. About 80% of cases were reported in winter months. The maximum cases were reported in the month of January followed by November and December. All the cases except one, died with a source of CO nearby and the person was inside a room or some closed space without ventilation. Source of CO was firepot and electric room heater in most of the cases. Some cases were of CO build inside the car with a running engine. Most of the cases occurred accidentally.

Conclusion:

Clustering of cases is seen in winters. Poisoning can occur in different ways. The study documents the various possibilities of CO poisoning and advocates community education targeting the high-risk groups and masses, especially during the winter season.

Protective Effect of Edaravone against Carbon Monoxide Induced Apoptosis in Rat Primary Cultured Astrocytes

Objective. To observe the protective effect of edaravone (Eda) on astrocytes after prolonged exposure to carbon monoxide (CO) and further to investigate the potential mechanisms of Eda against CO-induced apoptosis. Methods. The rat primary cultured astrocytes were cultured in vitro and exposed to 1% CO for 24 h after being cultured with different concentrations of Eda. MTT assay was used to detect the cytotoxicity of CO. Flow cytometry was used to detect the apoptosis rate, membrane potential of mitochondria, and ROS level. The mRNA and protein expressions of Bcl-2, Bax, and caspase-3 were assessed by real-time PCR and Western blotting analysis, respectively. Results. Eda can significantly suppress cytotoxicity of CO, and it can significantly increase membrane potential of mitochondria and Bcl-2 expressions and significantly suppress the apoptosis rate, ROS level, Bax, and caspase-3 expressions. Conclusion. Eda protects against CO-induced apoptosis in rat primary cultured astrocytes through decreasing ROS production and subsequently inhibiting mitochondrial apoptosis pathway.