Carbon monoxide-related hospitalizations in the U.S.: evaluation of a web-based query system for public health surveillance

Diagnostic value of systemic immune-inflammation index and red cell distribution width-lymphocyte ratio in predicting troponin elevation in carbon monoxide poisoning

Purpose: The aim of our study was to assess the significant value of the systemic inflammatory index (SII) and red cell distribution width/lymphocyte ratio (RLR) in patients with carbon monoxide poisoning (COP). Materials and Methods: Based on a retrospective cross-sectional study design, this study was conducted among patients 18 years and older who presented to the hospital's emergency department with COP. The patients were separated into troponin positive and negative groups as an outcome of serial troponin measurements. Receiver operating characteristic (ROC) analysis was used to determine the cut-off value of neutrophil/lymphocyte ratio (NLR), monocyte-to-lymphocyte ratio (MLR), RLR, and SII to predict troponin positivity. Results: This study included 195 patients with CO exposure, 50 of whom had positive troponin tests. It was discovered that the diagnostic power of NLR, RLR, MLR, and SII was acceptable for identifying troponin positivity (AUC: 0.71-0.77). According to ROC curve comparisons, there was no diagnostic difference between these inflammatory biomarkers. Increased NLR, RLR, MLR, and SII were found to be independent predictors of troponin positivity after CO exposure (Odds ratio respectively: 8.65, 4.31, 7.24, 6.31). Conclusion: SII and RLR, which are simple, inexpensive, and easily accessible parameters, are valuable in predicting troponin positivity in COP cases.

Temporal trends and demographic risk factors for hospital admissions due to carbon monoxide poisoning in England

Unintentional non-fire related (UNFR) carbon monoxide (CO) poisoning is a preventable cause of morbidity and mortality. Epidemiological data on UNFR CO poisoning can help monitor changes in the magnitude of this burden, particularly through comparisons of multiple countries, and to identify vulnerable sub-groups of the population which may be more at risk. Here, we collected data on age- and sex- specific number of hospital admissions with a primary diagnosis of UNFR CO poisoning in England (2002-2016), aggregated to small areas, alongside area-level characteristics (i.e. deprivation, rurality and ethnicity). We analysed temporal trends using piecewise log-linear models and compared them to analogous data obtained for Canada, France, Spain and the US. We estimated age-standardized rates per 100,000 inhabitants by area-level characteristics using the WHO standard population (2000-2025). We then fitted the Besag York Mollie (BYM) model, a Bayesian hierarchical spatial model, to assess the independent effect of each area-level characteristic on the standardized risk of hospitalization. Temporal trends showed significant decreases after 2010. Decreasing trends were also observed across all countries studied, yet France had a 5-fold higher risk. Based on 3399 UNFR CO poisoning hospitalizations, we found an increased risk in areas classified as rural (0.69, 95% CrI: 0.67; 0.80), highly deprived (1.77, 95% CrI: 1.66; 2.10) or with the largest proportion of Asian (1.15, 95% CrI: 1.03; 1.49) or Black population (1.35, 95% CrI: 1.20; 1.80). Our multivariate approach provides strong evidence for the identification of vulnerable populations which can inform prevention policies and targeted interventions.

Temporal trends and demographic risk factors for hospital admissions due to carbon monoxide poisoning in England

Unintentional non-fire related (UNFR) carbon monoxide (CO) poisoning is a preventable cause of morbidity and mortality. Epidemiological data on UNFR CO poisoning can help monitor changes in the magnitude of this burden, particularly through comparisons of multiple countries, and to identify vulnerable sub-groups of the population which may be more at risk. Here, we collected data on age- and sex- specific number of hospital admissions with a primary diagnosis of UNFR CO poisoning in England (2002-2016), aggregated to small areas, alongside area-level characteristics (i.e. deprivation, rurality and ethnicity). We analysed temporal trends using piecewise log-linear models and compared them to analogous data obtained for Canada, France, Spain and the US. We estimated age-standardized rates per 100,000 inhabitants by area-level characteristics using the WHO standard population (2000-2025). We then fitted the Besag York Mollie (BYM) model, a Bayesian hierarchical spatial model, to assess the independent effect of each area-level characteristic on the standardized risk of hospitalization. Temporal trends showed significant decreases after 2010. Decreasing trends were also observed across all countries studied, yet France had a 5-fold higher risk. Based on 3399 UNFR CO poisoning hospitalizations, we found an increased risk in areas classified as rural (0.69, 95% CrI: 0.67; 0.80), highly deprived (1.77, 95% CrI: 1.66; 2.10) or with the largest proportion of Asian (1.15, 95% CrI: 1.03; 1.49) or Black population (1.35, 95% CrI: 1.20; 1.80). Our multivariate approach provides strong evidence for the identification of vulnerable populations which can inform prevention policies and targeted interventions.

Carbon monoxide poisoning surveillance in the Veterans Health Administration, 2010-2017

BACKGROUND

Exposure to carbon monoxide (CO), the odorless, colorless gas resulting from incomplete combustion of hydrocarbons, is preventable. Despite the significant risk of morbidity and mortality associated with CO poisoning, there currently exists no active national CO surveillance system in the United States (U.S.). Our study aims to use electronic health record data to describe the epidemiology of CO poisoning in the Veterans Health Administration healthcare population.

METHODS

We identified unique inpatient and outpatient encounters coded with International Classification of Diseases (ICD) codes for CO poisoning and analyzed relevant demographic, laboratory, treatment, and death data from January 2010 through December 2017 for Veterans across all 50 U.S. states and Puerto Rico. Statistical methods used were 95% CI calculations and the two-tailed z test for proportions.

RESULTS

We identified 5491 unique patients with CO poisoning, of which 1755 (32%) were confirmed/probable and 3736 (68%) were suspected. Unintentional poisoning was most common (72.9%) overall. Age less than 65 years, residence in Midwest U.S. Census region versus South or West, and winter seasonal trend were characteristics associated with confirmed/probable CO poisoning. Twenty-six deaths (1.5%) occurred within 30 days of confirmed/probable CO poisoning and were primarily caused by cardiovascular events (42%) or anoxic encephalopathy (15%).

CONCLUSIONS

Our findings support the use of ICD-coded data for targeted CO poisoning surveillance, however, improvements are needed in ICD coding to reduce the percentage of cases coded with unknown injury intent and/or CO poisoning source. Prevalence of CO poisoning among Veterans is consistent with other U.S. estimates. Since most cases are unintentional, opportunities exist for provider and patient education to reduce risk.

National unintentional carbon monoxide poisoning estimates using hospitalization and emergency department data

Unintentional non-fire-related (UNFR) carbon monoxide (CO) poisoning is a leading cause of poisoning in the US and a preventable cause of death. We generated national estimates of accidental CO poisoning and characterized the populations most at risk. UNFR CO poisoning cases were assessed using hospitalization and emergency department (ED) data from the Healthcare Costs and Utilization Project National Inpatient Sample and Nationwide Emergency Department Sample databases. We used hospitalization data from 2003 to 2013 and ED data from 2007 to 2013. We calculated trends using a linear regression of UNFR CO poisonings over the study period and age-adjusted rates using direct standardization and U.S. Census Bureau estimates. During 2003-2013, approximately 14,365 persons (4.1 cases/million annually) with confirmed or probable UNFR CO poisoning were admitted to hospitals and the annual rate of poisonings showed a weak downward trend (p = 0.12). During 2007-2013, approximately 101,847 persons (48.3 visits/million annually) visited the ED and the annual rate of poisonings showed a significant downward trend (p ≤ 0.01). Most UNFR CO hospital cases involved patients who were older (aged 45-64 years), white, male, or living in the South or Midwest. Overall, the rate of hospitalizations did not change over the study period. Unintentional CO poisoning is preventable and these cases represent the most recent national estimates. ED visits declined over the study period, but the hospitalization rates did not change. This emphasizes the need for prevention efforts, such as education in the ED setting, increased use of CO alarms, and proper use and maintenance of fuel-powered household appliances.

Clinical chameleons: an emergency medicine focused review of carbon monoxide poisoning

Carbon monoxide (CO) is a colorless, odorless gas that is found in the environment, in the home, and in the human body as a normal part of mammalian metabolism. Poisoning from CO, a common exposure, is associated with significant morbidity and mortality if not recognized and treated in a timely manner. This review evaluates the signs and symptoms of CO poisoning, conditions that present similar to CO poisoning, and an approach to the recognition and management for CO poisoning. CO poisoning accounts for thousands of emergency department visits annually. If not promptly recognized and treated, it leads to significant morbidity and mortality. CO poisoning poses a challenge to the emergency physician because it classically presents with non-specific symptoms such as headache, dizziness, nausea, and vomiting. Due to nonspecific presentations, it is easily mistaken for other, more benign diagnoses such as viral infection. The use of specific historical clues such as exposure to non-conventional heat sources or suicide attempts in garages, as well as the use of targeted diagnostic testing with CO-oximetry, can confirm the diagnosis of CO poisoning. Once diagnosed, treatment options range from observation to the use of hyperbaric oxygen. CO poisoning is an elusive diagnosis. This review evaluates the signs and symptoms CO poisoning, common chameleons or mimics, and an approach to management of CO poisoning.

Carbon monoxide toxicity after lighting coals at a hookah bar

INTRODUCTION

Unintentional non-fire-related (UNFR) carbon monoxide (CO) poisonings continue to account for a significant health and economic burden in the United States. While most of these poisonings are related to faulty central heating or water heaters in private dwellings, less common sources should also be considered when a patient presents with any signs or symptoms suggestive of CO toxicity.

CASE REPORT

The authors present a case where a patient was found to have severe CO poisoning, a COHgb level of 33.8 %, after lighting coals for a water pipe called a hookah. The patient was initially unconscious and was found to have electrocardiogram (ECG) changes consistent with cardiac ischemia that resolved following treatment with hyperbaric oxygen therapy.

DISCUSSION

In recent years, hookah bars have gained in popularity, especially in urban areas and around college campuses. This was the first case to identify the potential occupational exposure of employees working at hookah bars to CO. Furthermore, the patient's COHb level of 33.8 % was higher than any previously reported in the literature with exposure via hookah pipe. The practitioner should consider CO poisoning in patients who smoke tobacco via a hookah and consider early hyperbaric oxygen therapy in those experiencing significant symptoms.

Mortality and hospital admission rates for unintentional nonfire-related carbon monoxide poisoning across Canada: a trend analysis

BACKGROUND

The epidemiology of mortality and morbidity from carbon monoxide poisoning in Canada has received little attention. Our objective was to evaluate trends in mortality and hospital admission rates for unintentional nonfire-related carbon monoxide poisoning across Canada.

METHODS

Age- and sex-standardized mortality (1981-2009) and hospital admission (1995-2010) rates by age group, sex and site of carbon monoxide exposure were calculated for each province and for all of Canada. We quantified the long-term trends by calculating the average annual percent change. Multivariable Poisson regression was used to estimate incidence rate ratios (IRRs) of carbon monoxide poisoning across age groups, sex and month of occurrence.

RESULTS

In Canada, there were 1808 unintentional nonfire-related carbon monoxide poisoning deaths between 1981 and 2009 and 1984 admissions to hospital between 1995 and 2010. Average annual decreases of 3.46% (95% confidence interval [CI] -4.59% to -2.31%) and 5.83% (95% CI -7.79% to -3.83%) were observed for mortality and hospital admission rates, respectively. Mortality (IRR 5.31, 95% CI 4.57 to 6.17) and hospital admission (IRR 2.77, 95% CI 2.51 to 3.03) rates were elevated in males compared with females. Decreased trends in the rates were observed for all sites of carbon monoxide exposure, but the magnitude of this decrease was lowest in residential environments. Deaths and admissions to hospital were most frequent from September to April, with peaks in December and January.

INTERPRETATION

Mortality and hospital admission rates for unintentional nonfire-related carbon monoxide poisoning in Canada have declined steadily. Continued efforts should focus on reducing carbon monoxide poisoning during the cooler months and in residential environments.

Implications of leading crop production practices on environmental quality and human health

Globally, much weight is currently being placed on agriculture to provide food for the growing population as well as feedstock for the bioenergy industry. Unfortunately, the intensification of agricultural operations to satisfy these growing needs has been associated with a number of environmental and human health risks. A review of publications on the subject was conducted and emphasis was placed on articles focusing on agriculture, environment, and public health as well as their interactions. Supporting information was also gathered from publications of various agricultural and environmental agencies. Agricultural practices with potential negative implications on the environment and human health were identified broadly as: (a) utilization of biosolids and animal manures, (b) use of agricultural chemicals, (c) management of post-harvest residue, (d) irrigation, and (e) tillage operations. Soil, water, and air contamination by nutrients, heavy metals, pathogens, and pesticides, as well as air contamination by particulate matters, noxious gases, and pathogens were among the leading environmental impacts. Some of the human-health impacts identified included neurological and reproductive defects, cardiovascular risks, cancers and other diseases (of kidney, liver, lung, and skin), skin allergies, gastroenteritis, and methemoglobinemia. Continual awareness on the impacts of the reviewed agricultural practices on environmental quality and human health and the implementation of experimentally-backed best management practices in agricultural systems remain indispensable.

National carbon monoxide poisoning surveillance framework and recent estimates

OBJECTIVES

Unintentional, non-fire-related (UNFR) carbon monoxide (CO) poisoning is a leading cause of poisoning in the United States. A comprehensive national CO poisoning surveillance framework is needed to obtain accurate estimates of CO poisoning burden and guide prevention efforts. This article describes the current national CO poisoning surveillance framework and reports the most recent national estimates.

METHODS

We analyzed mortality data from the National Vital Statistics System multiple cause-of-death file, emergency department (ED) and hospitalization data from the Healthcare Cost and Utilization Project's Nationwide Emergency Department Sample and Nationwide Inpatient Sample, hyperbaric oxygen treatment (HBOT) data from HBOT facilities, exposure data from the National Poison Data System, and CO alarm prevalence data from the American Housing Survey and the National Health Interview Survey.

RESULTS

In the United States, 2,631 UNFR CO deaths occurred from 1999 to 2004, an average of 439 deaths annually. In 2007, there were 21,304 (71 per one million population) ED visits and 2,302 (eight per one million population) hospitalizations for confirmed cases of CO poisoning. In 2009, 552 patients received HBOT, and from 2000 to 2009, 68,316 UNFR CO exposures were reported to poison centers. Most nonfatal poisonings were among children (<18 years of age) and females; hospitalizations and deaths occurred more frequently among males and elderly people (>65 years of age). More poisonings occurred during winter months and in the Midwest and Northeast.

CONCLUSIONS

UNFR CO poisoning poses a significant public health burden. Systematic evaluation of data sources coupled with modification and expansion of the surveillance framework might assist in developing effective prevention strategies.

A review of disaster-related carbon monoxide poisoning: surveillance, epidemiology, and opportunities for prevention

OBJECTIVES

We conducted a systematic literature review to better understand aspects of disaster-related carbon monoxide (CO) poisoning surveillance and determine potentially effective prevention strategies.

METHODS

This review included information from 28 journal articles on disaster-related CO poisoning cases occurring between 1991 and 2009 in the United States.

RESULTS

We identified 362 incidents and 1888 disaster-related CO poisoning cases, including 75 fatalities. Fatalities occurred primarily among persons who were aged 18 years or older (88%) and male (79%). Hispanics and Asians accounted for 20% and 14% of fatal cases and 21% and 7% of nonfatal cases, respectively. Generators were the primary exposure source for 83% of fatal and 54% of nonfatal cases; 67% of these fatal cases were caused by indoor generator placement. Charcoal grills were a major source of exposure during winter storms. Most fatalities (94%) occurred at home. Nearly 89% of fatal and 53% of nonfatal cases occurred within 3 days of disaster onset.

CONCLUSIONS

Public health prevention efforts could benefit from emphasizing predisaster risk communication and tailoring interventions for racial, ethnic, and linguistic minorities. These findings highlight the need for surveillance and CO-related information as components of disaster preparedness, response, and prevention.

A survey of residential carbon monoxide detector utilization among Connecticut Emergency Department patients

CONTEXT

The use of carbon monoxide detectors may prevent deaths due to unintentional carbon monoxide poisoning. Currently, there is limited data regarding the characteristics of residential carbon monoxide detector use.

OBJECTIVE

To determine the characteristics of residential carbon monoxide detector use.

METHODS

A survey was administered to a convenience, cross-sectional sample of Emergency Department patients between June and August 2011. Inclusion criteria included patients who were older than 18 years, able to understand written or spoken English or Spanish, and lived in independent residential settings. Survey questions assessed the presence or absence of carbon monoxide and smoke detectors within the participant's home, the frequency of regular battery changes for both devices, location of carbon monoxide detectors within the home, and reasons for not installing carbon monoxide detectors (if applicable). Correlations between racial background, geographical area of residence (urban versus suburban), and income were also assessed.

RESULTS

A total of 1030 patients were surveyed. While 97.8% of respondents reported smoke detector use, only 44.4% had home carbon monoxide detectors installed. Only 17.2% had carbon monoxide detectors installed in or near their sleeping area, the correct location for detector placement. Carbon monoxide detector usage was found to be lowest among households earning less than $25,999 per year (27.3% reported having detectors), non-Caucasians (only 42.0% of African-Americans and 24.7% of Hispanics surveyed reported using detectors compared with 57.8% of Caucasians), renters, and urban residents. Reasons given for not having a carbon monoxide detector varied; many answers were consistent with a lack of awareness of the importance of using carbon monoxide detectors.

DISCUSSION AND CONCLUSIONS

Residential carbon monoxide detectors were underutilized compared to smoke detectors. Increased public education, especially for minorities and lower income populations, is necessary regarding the use of carbon monoxide detectors for poisoning prevention.

Carbon monoxide poisoning: case studies and review

This article describes carbon monoxide poisoning. Using a case study approach, the article covers pathophysiology, epidemiology, clinical presentation, and complications. A nursing care plan is presented to guide the critical care nurse in the care of patients in this type of condition.

Evaluation of animal and public health surveillance systems: a systematic review

Disease surveillance programmes ought to be evaluated regularly to ensure they provide valuable information in an efficient manner. Evaluation of human and animal health surveillance programmes around the world is currently not standardized and therefore inconsistent. The aim of this systematic review was to review surveillance system attributes and the methods used for their assessment, together with the strengths and weaknesses of existing frameworks for evaluating surveillance in animal health, public health and allied disciplines. Information from 99 articles describing the evaluation of 101 surveillance systems was examined. A wide range of approaches for assessing 23 different system attributes was identified although most evaluations addressed only one or two attributes and comprehensive evaluations were uncommon. Surveillance objectives were often not stated in the articles reviewed and so the reasons for choosing certain attributes for assessment were not always apparent. This has the potential to introduce misleading results in surveillance evaluation. Due to the wide range of system attributes that may be assessed, methods should be explored which collapse these down into a small number of grouped characteristics by focusing on the relationships between attributes and their links to the objectives of the surveillance system and the evaluation. A generic and comprehensive evaluation framework could then be developed consisting of a limited number of common attributes together with several sets of secondary attributes which could be selected depending on the disease or range of diseases under surveillance and the purpose of the surveillance. Economic evaluation should be an integral part of the surveillance evaluation process. This would provide a significant benefit to decision-makers who often need to make choices based on limited or diminishing resources.

Hospital burden of unintentional carbon monoxide poisoning in the United States, 2007

BACKGROUND

Unintentional, non-fire-related (UNFR) carbon monoxide (CO) poisoning is a leading cause of poisoning in the United States, but the overall hospital burden is unknown. This study presents patient characteristics and the most recent comprehensive national estimates of UNFR CO-related emergency department (ED) visits and hospitalizations.

METHODS

Data from the 2007 Nationwide Inpatient and Emergency Department Sample of the Hospitalization Cost and Utilization Project were analyzed. The Council of State and Territorial Epidemiologists' CO poisoning case definition was used to classify confirmed, probable, and suspected cases.

RESULTS

In 2007, more than 230,000 ED visits (772 visits/million) and more than 22,000 hospitalizations (75 stays/million) were related to UNFR CO poisoning. Of these, 21,304 ED visits (71 visits/million) and 2302 hospitalizations (8 stays/million) were confirmed cases of UNFR CO poisoning. Among the confirmed cases, the highest ED visit rates were among persons aged 0 to 17 years (76 visits/million) and 18 to 44 years (87 visits/million); the highest hospitalization rate was among persons aged 85 years or older (18 stays/million). Women visited EDs more frequently than men, but men were more likely to be hospitalized. Patients residing in a nonmetropolitan area and in the northeast and midwest regions of the country had higher ED visit and hospitalization rates. Carbon monoxide exposures occurred mostly (>60%) at home. The hospitalization cost for confirmed CO poisonings was more than $26 million.

CONCLUSION

Unintentional, non-fire-related CO poisonings pose significant economic and health burden; continuous monitoring and surveillance of CO poisoning are needed to guide prevention efforts. Public health programs should emphasize CO alarm use at home as the main prevention strategy.