Risk of Venous Thromboembolism After Carbon Monoxide Poisoning: A Nationwide Population-Based Study

Bilateral superficial temporal vein thrombosis after acute carbon monoxide poisoning and prolonged immobilisation: a case report

A prolonged stay on the ground after acute carbon monoxide poisoning (COP) is a high-risk situation for venous thromboembolism (VTE), but unusual-site venous thrombosis is rare in this setting. An 81-year-old woman with no personal or family history of VTE who lied on the ground for several hours following massive COP had painful and oedematous temples, so a Doppler ultrasound was prompted and revealed a bilateral superficial temporal vein (STV) thrombosis. There was no heart failure, trauma, inflammatory disease, infection, or vascular malformation. The thrombosis regressed on fondaparinux 2.5 mg given as a daily subcutaneous injection for 45 days. Our observation emphasizes the need to look not only for arteritis but also for venous thrombosis before any temporal pain. STV thrombosis has been reported four times to date. We report the first case of bilateral STV thrombosis in the setting of massive COP and prolonged immobilisation in an elderly patient.

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 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.

Incidence, timing, location, risk factors, and nomogram of lower extremity deep venous thrombosis after acute carbon monoxide poisoning

INTRODUCTION

Data on lower extremity deep venous thrombosis (DVT) following acute carbon monoxide (CO) poisoning are lacking. This study aimed to identify the incidence rate, timing, locations, risk factors, and nomogram of lower extremity DVT after acute CO poisoning.

METHODS

A total of 203 patients with acute CO poisoning from October 2019 to April 2021 were included in this retrospective study. Multivariate logistic regression analysis was performed to identify the independent risk factors associated with lower extremity DVT. Nomogram was drawn and area under the curve (AUC) was calculated to predict lower extremity DVT.

RESULTS

Overall, 14.3% (29/203) had lower extremity DVT, with incidence rates of 2.5% (5/203) for proximal DVT and 11.8% (24/203) for distal DVT. The lower extremity DVTs involved intermuscular vein in 28 patients, popliteal vein in 5 patients, and posterior tibial vein in 3 patients. The mean time from end of exposure to diagnosis of lower extremity DVT was 1.24 days. Among 29 lower extremity DVT cases, 6 (23.1%) DVT cases had thrombolysis. Multivariate logistic regression analysis revealed that long coma duration (P < 0.001) and high D-dimer levels (P < 0.001) were significantly associated with lower extremity DVT. The discrimination of nomogram was good with AUC of 0.93 (95% CI, 0.89-0.98).

CONCLUSION

Clinicians should be aware of and concerned with lower extremity DVT after acute CO poisoning, especially in patients with long coma duration and high D-dimer levels.

Associations between ambient air pollution, meteorology, and daily hospital admissions for ischemic stroke: a time-stratified case-crossover study in Beijing

Air pollution and ischemic stroke (IS) are both vital factors affecting the health of Beijing citizens. This study aims at exploring the associations between air pollution, meteorology, and the hospital admission of IS (IS HA). Information on 476,659 IS inpatients in secondary and higher hospitals in Beijing from 2013 to 2018 were collected. A time-stratified case-crossover design with the generalized additive model and the distributed lag nonlinear model were used. In the single-pollutant models, an inter-quartile range increase in O_3, SO₂, CO, and NO₂ resulted in a significant highest increase in IS HA by 2.23% (95% CI: 1.56%, 2.90%), 1.53% (95% CI: 1.12%, 1.95%), 1.05% (95% CI: 0.70%, 1.40%), and 0.51% (95% CI: 0.24%, 0.79%) on the day of pollution, so did PM_2.5 and PM₁₀ by 1.13% (95% CI: 0.68%, 1.59%) and 1.19% (95% CI: 0.74%, 1.64%) at a lag of 0-5 days. There was a nonlinear relationship between meteorology and IS HA. In the multivariate model, the cumulative relative risks with a maximum lag time of 21 days of PM_2.5 and NO₂ were 1.11 (95% CI: 1.04, 1.19) and 0.88 (95% CI: 0.82, 0.94), while the effects of SO₂, O₃, and meteorology were insignificant. The findings suggested that particulate pollutants could increase the risk of IS, and the elderly were more sensitive to it, while the results of gaseous pollutants are still discordant. The control of air pollution and the protection of susceptible populations should receive higher attention from policymakers.

Air pollution increases the risk of pulmonary embolism: a meta-analysis

OBJECTIVES

Air pollution can lead to many cardiovascular and respiratory diseases, but the impact of air pollution on pulmonary embolism is still uncertain. We conducted a meta-analysis to assess the relationship between air pollution and pulmonary embolism.

CONTENT

We searched PubMed, EMBASE, Web of Science, and the Cochran Library for citations on air pollutants (carbon monoxide, sulfur dioxide, nitrogen dioxide, ozone and particulate matter) and pulmonary embolism. A total of nine citations met the inclusion criteria. There is no evidence of bias. CO, SO₂, PM₁₀ and PM_2.5 had no significant effect on the occurrence of pulmonary embolism. NO₂ and O₃ can increase the risk of pulmonary embolism to a small extent.

SUMMARY

This meta-analysis suggests that some air pollutants are associated with an increased risk of pulmonary embolism.

OUTLOOK

Reducing air pollution and improving air quality can effectively reduce the risk of pulmonary embolism.

Carbon Monoxide Poisoning and Developing Ischemic Heart Disease: A Nationwide Population-Based Nested Case-Control Study

Although there are several case reports showing that carbon monoxide (CO) poisoning causes ischemic heart disease (IHD), no large-scale epidemiological studies have shown a significant association between the two. To investigate the association between CO poisoning and IHD, a nested case-control study of 28,113 patients who experienced CO poisoning and 28,113 controls matched by sex and age was performed using the nationwide health database of South Korea. Based on a conditional logistic regression, there was a significantly higher risk of IHD among the CO poisoning group than among the control group (adjusted hazard ratio [HR], 2.16; 95% confidence interval [CI], 1.87–2.49). The risk of IHD after CO poisoning was higher among the younger age group under 40 years (adjusted HR, 4.85; 95% CI, 3.20–7.35), and it was much greater among those with comorbidities (adjusted HR, 10.69; 95% CI, 2.41–47.51). The risk of IHD was the highest within the first two years after CO poisoning (adjusted HR, 11.12; 95% CI, 4.54–27.22). Even if more than six years had passed, the risk was still significantly higher than among the control group (adjusted HR, 1.55; 95% CI, 1.27–1.89). The analyses imply that CO poisoning is associated with an increased risk of IHD.

Risk factors for venous thromboembolism after carbon monoxide poisoning: A nationwide population-based study

Introduction:

The risk of venous thromboembolism increases after acute carbon monoxide poisoning. However, studies on the characteristics of patients who develop venous thromboembolism after carbon monoxide poisoning are rare. The aim of this study was to identify the risk factors for venous thromboembolism within 3 months after carbon monoxide poisoning.

Methods:

This is a population-based study that employed nationwide claims data from South Korea. Among the carbon monoxide poisoning patients (⩾18 years), the characteristics of the groups with and without venous thromboembolism (pulmonary embolism or deep vein thrombosis) were identified. All the significant variables in the univariable analysis were included in the multivariable logistic regression to determine the risk factors for venous thromboembolism occurrence.

Results:

Among the 24,232 carbon monoxide poisoning patients, 130 subjects developed venous thromboembolism within 90 days of their carbon monoxide poisoning diagnosis. The significant risk factors for venous thromboembolism in the multivariable analysis were age (adjusted odds ratio (aOR) = 1.01; 95% confidence interval (CI) = 1.003–1.03), intensive care unit admission (aOR = 3.80; 95% CI = 2.34–6.12), length of stay (aOR = 1.02; 95% CI = 1.0001–1.04), congestive heart failure (aOR = 2.17; 95% CI = 1.36–3.42), and cancer (aOR = 1.94; 95% CI = 1.10–3.22). The adjusted odds ratios for intensive care unit admission for patients with pulmonary embolism and deep vein thrombosis were 3.05 (95% CI = 1.61–5.61) and 5.60 (95% CI = 2.89–10.90), respectively.

Conclusion:

Patients with older age, intensive care unit admission, a longer length of stay, congestive heart failure, or cancer are at greater risk of developing venous thromboembolism after carbon monoxide poisoning. In particular, intensive care unit admission was the strongest risk factor for venous thromboembolism, pulmonary embolism, and deep vein thrombosis. Monitoring and administering prophylactic treatments to prevent venous thromboembolism would be helpful in high-risk in carbon monoxide poisoning patients.

Association Between Carbon Monoxide Intoxication and Incidence of Ischemic Stroke: A Retrospective Nested Case-Control Study in South Korea

OBJECTIVES

Severe neurological sequelae occur in patients with carbon monoxide (CO) intoxication; however, whether the latter increases the long-term risk of developing ischemic stroke is unclear. We investigated the association between CO intoxication and ischemic stroke using data from the Korean National Health Information Database.

MATERIALS AND METHODS

We performed a retrospective, nested case-control study of 27,984 individuals treated for CO intoxication and 27,984 sex- and age-matched controls. Initially, we calculated the overall incidence and hazard ratio (HR) of ischemic stroke using conditional logistic regression. Thereafter, we calculated the incidences and HRs according to covariates and follow-up periods.

RESULTS

The CO intoxication group had a significantly higher risk of developing ischemic stroke than the control group (adjusted HR 2.31, 95% CI [confidence interval] = 2.01-2.65). Male sex (adjusted HR 2.73, 95% CI = 2.23-3.34), age <40 (adjusted HR 3.53, 95% CI = 2.15-5.82), low income (adjusted HR 2.55, 95% CI = 1.56-4.15), comorbidities (adjusted HR 2.59, 95% CI = 1.48-4.52), and current smokers (adjusted HR 3.55, 95% CI = 1.67-7.60) had a higher risk of ischemic stroke. The risk of ischemic stroke was highest within 2 years after CO intoxication (adjusted HR 7.47, 95% CI = 2.76-20.26), and even >6 years after, the risk remained significantly higher than in the control group (adjusted HR 1.84, 95% CI = 1.53-2.20).

CONCLUSIONS

CO intoxication and the long-term risk of ischemic stroke are associated.

Stroke Incidence in Survivors of Carbon Monoxide Poisoning in South Korea: A Population-Based Longitudinal Study

Background

Carbon monoxide (CO) poisoning is a suspected risk factor for stroke. However, the association between stroke occurrence and carbon monoxide poisoning remains unclear. This nationwide study in Korea analyzed the incidence of stroke in survivors of CO poisoning.

Material/Methods

In this nationwide, population-based longitudinal study, the database of the Health Insurance Review and Assessment Service was searched to identify patients diagnosed with CO poisoning from 2012 to 2018. Their incidence of ischemic and hemorrhagic strokes, the patterns of stroke incidences, the annual incidence rates in sequential time, the standardized incidence ratio (SIR), and the effects of hyperbaric oxygen therapy (HBOT) were analyzed.

Results

Of the 29 301 patients diagnosed with CO poisoning during the study period, 984 (3.36%) were diagnosed with stroke after CO poisoning, with approximately 50% occurring within 1 year after CO poisoning. The overall SIR for stroke was 19.49 (95% confidence interval [CI], 17.92–21.12) during the first year, decreasing to 5.64 (95% CI, 4.75–6.66) during the second year. Overall stroke hazard ratio (HR) in the patients admitted to the ICU for CO poisoning was 2.28 (95% CI, 1.19–2.27), compared with 2.35 (95% CI, 1.94–2.84) for ischemic stroke and 1.76 (95% CI, 1.11–2.78) for hemorrhagic stroke. Cumulative HRs did not differ between patients who were and were not treated with HBOT for stroke.

Conclusions

CO poisoning is a high-risk factor for the development of stroke, evidenced by high incidences of stroke after CO poisoning. Practical strategies for preventing stroke after CO poisoning are needed, because stroke after CO poisoning affects adults of almost all ages, significantly increasing their socioeconomic burden.