Higher Carboxyhemoglobin Levels Research Articles

Biochemical parameters and clinical outcomes of carbon monoxide poisoning in special groups: children, pregnant women, and the elderly.

Carbon monoxide (CO), a toxic gas, poses a significant threat to human health. Children, pregnant women, and elderly individuals are particularly vulnerable to this toxicity. This study aims to evaluate the demographic and clinical characteristics of pediatric, pregnant, and geriatric patients. The study included pediatric, pregnant, and geriatric patients with a confirmed diagnosis of CO poisoning, excluding those with complete file data and those with carboxyhemoglobin (COHb) levels below 5% (for children and pregnant patients) and 10% (for elderly patients). Patients aged < 18 years, > 65 years, and pregnant patients admitted to the adult and pediatric emergency departments were included in the study; statistical analyses were conducted using SPSS Inc., with a p-value of < 0.05 considered statistically significant. For pediatric patients, a statistically significant difference was observed between the two groups in terms of their main complaints, which were primarily attributed to neurological and general symptoms. A positive correlation was found between follow-up time and several factors, including white blood cell (WBC) count and troponin, lactate, lactate dehydrogenase (LDH), and COHb levels. For pregnant patients, no in-hospital mortality was observed in the patients included in this study. A significant negative correlation was identified between age and both COHb and hemoglobin (Hb) levels. A strong positive correlation was found between the COHb levels and hospital follow-up time. For elderly patients, no significant differences were found between the two treatment modalities. Notably, higher COHb levels on admission were associated with a more fatal in-hospital course, with COHb levels > 40% of all patients requiring intubation. Vulnerable populations are at increased risk of exposure to CO, and the study results emphasize the necessity of heightened awareness and preventive measures to safeguard these individuals from CO poisoning.

Pathological alterations and COHb evaluations as tools for investigating fire-related deaths in veterinary forensic pathology.

Fire-related deaths are usually a consequence of carbon monoxide (CO) poisoning or shock from thermal injuries. In humans, high levels of carboxyhemoglobin (COHb) concentrations in the blood can support a diagnosis of CO poisoning. In veterinary medicine, few studies investigated the pathological changes and blood COHb% in fire victims, and no data are available on post-mortem changes in blood gas composition due to fire. This study aims to investigate the pathological changes and COHb levels in both animal victims of fire and cadavers experimentally exposed to fire. For this purpose, dogs were selected and subdivided into three groups. Group A comprised 9 adult dogs, and Group B comprised 7 puppies that died under fire-related conditions. Group C was represented by 4 dog cadavers experimentally exposed to heat and smoke. A complete macroscopic, histological, and COHb evaluation were performed on each animal. Animals in Groups A and B showed cherry-red discoloration, thermal-injuries and soot deposits along the respiratory tract. Animals in Group C showed thermal injuries and soot deposits limited to the upper respiratory tract. The mean COHb% values in cadavers in Group C were lower than those observed in the other groups but higher compared to the values detected before the heat and smoke treatment. These findings suggest that both pathological changes and COHb analysis are valid tools for investigating fire-related deaths in dogs. However, the increase of COHb levels in cadavers exposed post-mortem to heat and smoke highlights how the COHb analysis should always be evaluated together with macroscopical and microscopical findings to avoid significant misjudgments in investigating fire-related fatalities in veterinary forensic practice.

Carboxyhemoglobin predicts oxygenator performance and imminent oxygenator change in extracorporeal membrane oxygenation

BackgroundThe continuous exposure of blood to a non-biological surface during extracorporeal membrane oxygenation (ECMO) may lead to progressive thrombus formation in the oxygenator, hemolysis and consequently impaired gas exchange. In most centers oxygenator performance is monitored only on a once daily basis. Carboxyhemoglobin (COHb) is generated upon red cell lysis and is routinely measured with any co-oximetry performed to surveille gas exchange and acid–base homeostasis every couple of hours. This retrospective cohort study aims to evaluate COHb in the arterial blood gas as a novel marker of oxygenator dysfunction and its predictive value for imminent oxygenator change.ResultsOut of the 484 screened patients on ECMO 89, cumulatively requiring 116 oxygenator changes within 1833 patient days, including 19,692 arterial COHb measurements were analyzed. Higher COHb levels were associated with lower post-oxygenator pO2 (estimate for log(COHb): − 2.176 [95% CI − 2.927, − 1.427], p < 0.0001) and with a shorter time to oxygenator change (estimate for log(COHb): − 67.895 [95% CI − 74.209, − 61.542] hours, p < 0.0001). COHb was predictive of oxygenator change within 6 h (estimate for log(COHb): 5.027 [95% CI 1.670, 15.126], p = 0.004).ConclusionCOHb correlates with oxygenator performance and can be predictive of imminent oxygenator change. Therefore, longitudinal measurements of COHb in clinical routine might be a cheap and more granular candidate for ECMO surveillance that should be further analyzed in a controlled prospective trial design.

Evaluation of a Portable Blood Gas Analyzer for Prehospital Triage in Carbon Monoxide Poisoning: Instrument Validation Study.

Carbon monoxide (CO) poisoning is an important cause of morbidity and mortality worldwide. Symptoms are mostly aspecific, making it hard to identify, and its diagnosis is usually made through blood gas analysis. However, the bulkiness of gas analyzers prevents them from being used at the scene of the incident, thereby leading to the unnecessary transport and admission of many patients. While multiple-wavelength pulse oximeters have been developed to discriminate carboxyhemoglobin (COHb) from oxyhemoglobin, their reliability is debatable, particularly in the hostile prehospital environment. The main objective of this pilot study was to assess whether the Avoximeter 4000, a transportable blood gas analyzer, could be considered for prehospital triage. This was a monocentric, prospective, pilot evaluation study. Blood samples were analyzed sequentially with 2 devices: the Avoximeter 4000 (experimental), which performs direct measurements on blood samples of about 50 µL by analyzing light absorption at 5 different wavelengths; and the ABL827 FLEX (control), which measures COHb levels through an optical system composed of a 128-wavelength spectrophotometer. The blood samples belonged to 2 different cohorts: the first (clinical cohort) was obtained in an emergency department and consisted of 68 samples drawn from patients admitted for reasons other than CO poisoning. These samples were used to determine whether the Avoximeter 4000 could properly exclude the diagnosis. The second (forensic) cohort was derived from the regional forensic center, which provided 12 samples from documented CO poisoning. The mean COHb level in the clinical cohort was 1.7% (SD 1.8%; median 1.2%, IQR 0.7%-1.9%) with the ABL827 FLEX versus 3.5% (SD 2.3%; median 3.1%, IQR 2.2%-4.1%) with the Avoximeter 4000. Therefore, the Avoximeter 4000 overestimated COHb levels by a mean difference of 1.8% (95% CI 1.5%-2.1%). The consistency of COHb readings by the Avoximeter 4000 was excellent, with an intraclass correlation coefficient of 0.97 (95% CI 0.93-0.99) when the same blood sample was analyzed repeatedly. Using prespecified cutoffs (5% in nonsmokers and 10% in smokers), 3 patients (4%) had high COHb levels according to the Avoximeter 4000, while their values were within the normal range according to the ABL827 FLEX. Therefore, the specificity of the Avoximeter 4000 in this cohort was 95.6% (95% CI 87%-98.6%), and the overtriage rate would have been 4.4% (95% CI 1.4%-13%). Regarding the forensic samples, 10 of 12 (83%) samples were positive with both devices, while the 2 remaining samples were negative with both devices. The limited difference in COHb level measurements between the Avoximeter 4000 and the control device, which erred on the side of safety, and the relatively low overtriage rate warrant further exploration of this device as a prehospital triage tool.

Carboxyhemoglobin Does Not Predict the Need of Mechanical Ventilation and Prognosis during COPD Exacerbation.

Background Carboxyhemoglobin (COHb) is a complex formed by the binding of carbon monoxide to hemoglobin in blood. Higher COHb levels have been associated with poor prognosis in a variety of pulmonary disorders. However, little is known regarding the prognostic significance of COHb among individuals with chronic obstructive pulmonary disease (COPD) exacerbation. Methods In a retrospective study, we evaluated associations of venous COHb levels on hospital admission with the need for invasive mechanical ventilation, in-hospital mortality, and rehospitalization, among 300 patients hospitalized for COPD exacerbation in internal medical wards. Results Rates of in-hospital death and 1-year recurrent hospitalizations were 11.0% and 59.6%, respectively. COHb levels were not significantly associated with in-hospital mortality (OR = 0.82, P=0.25, 95% CI 0.59–1.15) or with 1-year rehospitalizations (OR = 0.91, P=0.18, 95% CI 0.79–1.04). The mean COHb level did not differ significantly between patients who needed invasive mechanical ventilation and those who were not invasively mechanically ventilated during the current hospitalization (2.01 ± 1.42% vs. 2.19 ± 1.68%, P=0.49). Conclusions Among patients hospitalized with COPD exacerbation in internal medicine wards, COHb levels on admission were not associated with invasive mechanical ventilation treatment, rehospitalizations, or mortality.

Impact of vehicular pollution on carboxyhemoglobin levels and respiratory response in urban cyclists

BACKGROUND AND AIM: The present case-crossover study evaluated changes in carboxyhemoglobin (COHb) levels and spirometry values of 37 volunteers caused by vehicular pollution on a bike path parallel to a road with a high vehicular flow in two exposure scenarios (high exposure on weekdays and low exposure on Sundays) in the city of Bogotá, Colombia METHODS: For each scenario, ultrafine particles (UFP), carbon monoxide (CO), nitrogen dioxide (NO2), sulfur dioxide (SO2), and carbon black concentrations were measured, as well as vehicular flow and speed at two points on the road of interest, to explore the possible associations among these variables and exposure to each pollutant. RESULTS:Significant differences were obtained for UFP, CO, NO2, and SO2 concentrations between the high- and low-exposure scenarios, and between the estimated exposure doses (EED) of UFP, CO, and SO2. A strong correlation was found between the EED of CO and the percentage change in COHb before and after each bike ride (r=0.7571). Concerning UFP, a greater weight of background pollution was found in the high exposure scenario, followed by the impact of meteorological variables, and emission sources along the road under study. CONCLUSIONS:To explain the variability of respiratory parameters, the only statistically significant model was obtained for peak expiratory flow (25-75%) of the forced expiratory maneuver (MMEF25-75%), having EED of CO and average UFP size as explanatory variables. Cyclists arrived at the endpoint of the ride with high COHb levels due to exposure to air pollutants along the route they used to arrive at the study site. KEYWORDS: Air pollution, Mixtures, Biomarkers of exposure, Respiratory outcomes, Short-term exposure

Carboxyhemglobin and Drainage Pressure During Venovenous Extracorporeal Membrane Oxygenation.

To the Editor: We read with interest the article1 recently published by Nisar et al. on ASAIO Journal. The authors describe the frequent development of carboxyhemoglobinemia in patients treated with venovenous (V-V) extracorporeal membrane oxygenation (ECMO). As highlighted in the article, high carboxyhemoglobin levels cause significant discrepancies between pulse oximetry and actual oxyhemoglobin levels. This may lead to erroneous interpretation of patient oxygenation when the latter is assessed noninvasively. Carboxyhemoglobinemia has been described since 19492 as a marker for hemolysis. Hemolysis during V-V ECMO occurs in up to 18% of patients.3 The principal causes of mechanical hemolysis during ECMO support include circuit components (oxygenator, pump,4 cannula size) as well as patient’s characteristics.5 Centrifugal pump could be a major source of hemolysis when rotating in unsuitable conditions. High rotation speed (e.g., >3000 rpm) may result in high negative pressures at the pump head, thus promoting hydrodynamic cavitation and a high level of hemolysis.6 We performed a retrospective analysis of prospectively collected data of our historical cohort of acute respiratory distress syndrome patients treated with V-V ECMO, to compare our findings with Nisar et al. We included adult patients admitted to our ECMO unit (Rianimazione Generale, ASST Monza, Italy) between 2014 and 2020. We excluded patients with veno-venoarterial ECMO and COVID-19 patients, who may present coagulopathy as a part of the underlying disease.7 Arterial blood gas (ABG) analysis was performed with the RAPIDPoint 500e System (Siemens Healthcare, Erlangen, Germany). Elevated carboxyhemoglobin was defined according to the authors’ threshold (i.e., >3%).1 Eighty-four patients (39% females, 53 ± 10 years) were included in our analysis. ECMO configuration was femoro-femoral (86% of patients) or femoro-jugular. Median duration of ECMO support was 20 days, ranging from 3 to 83 days. Average blow flow was 3.5 ± 0.5 (2,520 ± 287 rpm), whereas mean drainage pressure was −42 ± 14 mm Hg. Overall, mean carboxyhemoglobin level was 1.1 ± 0.8%. Carboxyhemoglobin level at ECMO connection was 0.6 ± 0.5%%, and its average increase was 0.011% for each ECMO day. Among 1,653 ABG analyses, carboxyhemoglobin was >3% in only 23 samples (1.4%). A carboxyhemoglobin higher than 3% occurred at least once in eight (9.5%) patients. In our study, we found a lower incidence of hemolysis compared with Nisar et al.1 This finding may have different explanations. First, at our institution, we are used to carefully monitor the drainage pressure and adjusting the ECMO blood flow to avoid drainage pressures lower than −60/−70 mm Hg. This may limit hemolysis due to hydrodynamic cavitation. Moreover, a minor difference due to technical reason (i.e., two different blood gas analyzers) cannot be excluded. In absence of recirculation, a BF of 3–4 L/min usually allows achieving a safe oxygenation in adult patients.8 If adequate drainage cannulae are used (i.e., 21–25 Fr), this blood flow range can be usually achieved with drainage pressure of −30 to −60 mm Hg.9,10 Therefore, we hypothesize that limiting the blood flow rate to maintain “safe” drainage pressures may help in reducing the increase of carboxyhemoglobinemia during the ECMO course.

Analysis of risk factors of mortality for pediatric burned patients with inhalation injury and comparison of different treatment protocols.

We present our approach of pediatric burned patients with the suspicion of inhalation injury. This retrospective study was conducted on children with the suspicion of inhalation injury admitted to our burn center from December 2009 to December 2019. We collected data on patient demographics, total burn surface area (TBSA), presence of inhalation injury, level of carboxyhemoglobin, grade of inhalation injury, duration of mechanical ventilation, reintubation rate, total length of hospital stay, and the mortality rate. We also reviewed the required treatment of patients with inhalation injury. A total of sixty pediatric burn patients were suspected inhalation injury were included in this retrospective study. 40 pa-tients included in the study were male. Age average of the patients was 87.7 months. Total burned surface area average was 32%. 46 of these patients had inhalation injury. Patients with larger cutaneous burn and needed early intubation have a higher risk of inhalation injury. There was no significant relation between inhalation injury grades and mortality and treatment protocols. Higher levels of car-boxyhemoglobin and larger TBSA are the risk factors for mortality at univariate analysis. Pediatric patient with inhalation injury whose TBSA is higher than 47.5% has a 5 times higher risk of mortality at multivariate analysis. This study demonstrated that TBSA is the risk factor that independently affects the mortality in pediatric patients with inhalation injury. Among the patients with higher than 47.5% burn surface area, the mortality rate rises 5 times.

CARBON MONOXIDE RELATED DEATHS IN ALQURAYYATE, SAUDI ARABIA FROM 2004 TO 2018

The current work aimed to study carbon monoxide (CO) related deaths in Alqurayyate during the period from 2004-2018. Among 461 autopsied cases, 52 cases [11.3%] show carboxy-hemoglobin (COHb) levels≥ 10%. Higher COHb levels were significantly more common among males, young and elderly and Saudi people [0.012, 0.009, and 0.3 respectively]. was the cause of death in 19 cases [4.1%] while CO poisoning was suggested as a contributing factor in another 33 [7.2%] deaths. The mode of deaths was mainly accidental [78.8%]. Houses were the most common place of death [63.5%] and most CO related deaths happened in the winter months [73.1%]. The most common suggested source for exposure to CO among carbon monoxide poisoning (COP) deaths were car exhaust [36.8%], followed by charcoal heaters [31.6%]. Regarding autopsy findings, the external appearance revealed cherry red hypostasis in only 26.9% of CO related cases. The most common findings were pulmonary edema, cerebral edema, and congested lungs [96.2,82.7, and 80.8 % respectively]. Therefore, COP remains a common cause of death, inspite of the safety precautions. More public awareness programs about COP are recommended. Also, COHb levels should be routinely estimated in the autopsied cases, especially with suggestive history and death scene.

Usefulness of N-terminal pro-B-type natriuretic peptide (NT-ProBNP) as a marker for cardiotoxicity and comparison with echocardiography in paediatric carbon monoxide poisoning.

To demonstrate the usefulness of N-Terminal Pro-B-Type natriuretic peptide (NT-proBNP) as an early biomarker of carbon monoxide-induced myocardial injury in children. It also aimed to identify the correlation between NT-proBNP and left ventricular systolic dysfunction findings shown by echocardiography. Prospective, observational study conducted at a paediatric emergency department between October 2017 and April 2019 which involved children aged 0-17 years. The patients were divided into three groups based on severity; mild, moderate and severe groups. The patient characteristics, carboxyhaemoglobin, CK-MB Mass (CKMB-M), troponin-T, and NT-proBNP levels were measured, and echocardiography was performed and left ventricular ejection fraction was measured. Sixty-nine patients and 60 healthy controls were included. Male gender, younger age, higher carboxyhaemoglobin levels, and altered mental status were found as independent predictors of carbon monoxide-induced myocardial injury. If the cut-off value for NT-proBNP level is >480 pg/ml, the sensitivity-specificity for decreased left ventricular ejection fraction, which is the strongest carbon monoxide-induced myocardial injury sign, were 100-96%, respectively. A high negative correlation was found between NT-proBNP levels and left ventricular ejection fraction (r=-0.769, p < 0.01) in the carbon monoxide poisoning group, and there was a positive correlation between the carboxyhaemoglobin and NT-proBNP levels (r = 0.583, p < 0.01). Echocardiography is an ideal tool and very sensitive, but its routine use is limited due to its non-availability. An increased level of NT-proBNP (>480pg/ml) may be useful as an ideal biomarker for early detection of carbon monoxide-induced myocardial injury sign and reduced left ventricular ejection fraction which is the most crucial point in making a decision on hyperbaric oxygen therapy.

Clinical Characteristics of Pediatric Patients With Carbon Monoxide Poisoning.

Carbon monoxide (CO) poisoning is a common and deadly form of poisoning that is often treated with hyperbaric oxygen. The characteristics of children exposed to CO and then treated with hyperbaric oxygen have not been delineated. The purpose of this study was to describe the clinical characteristics of children treated with hyperbaric oxygen therapy for CO poisoning at a regional hyperbaric referral center. The study is based on a retrospective review of data extracted from the medical records of children (age <19 years) who were referred to our center for hyperbaric oxygen therapy for CO poisoning between 2008 and 2013. Inferential analyses were used to compare demographic characteristics, serum carboxyhemoglobin (COHb) levels, and presenting symptoms. Forty-seven children met our study criteria. Their mean age was 8.9 years, and their mean COHb level was 14.3% (range, 3.4%-30.1%). Severity of symptoms did not correlate with serum COHb levels; however, neurologic symptoms at presentation were more common in patients with a COHb level greater than 25%. There was a correlation between increasing age and higher COHb levels and between COHb and lactate levels. Our retrospective review of patients' records showed no correlation of serum COHb levels with symptoms on presentation; however, a correlation was found between increasing age and COHb level as well as lactate level and COHb level.

Critically High Carboxyhemoglobin Level following Extensive Hysteroscopic Myomectomy

Studies have demonstrated that during hysteroscopic myomectomy with bipolar diathermy, carbon monoxide is produced and enters the patient's circulation. However, little is known regarding the immediate or long-term sequelae of transient rises in carboxyhemoglobin levels during hysteroscopic surgery. This paper aims to suggest recommendations for acute evaluation, management, patient counseling, and future research. We present a case of a 36-year-old woman (Gravida 0, Para 0) with abnormal uterine bleeding-leiomyoma and resultant anemia, undergoing hysteroscopic resection of a large submucous myoma. During surgery, the patient was found to have a critically elevated level of carboxyhemoglobin and accompanying electrocardiogram derangements. She was managed with prolonged intubation, 100% O2, and trending of her carboxyhemoglobin levels before extubation. This demonstrates the importance of being cognizant of the potentially toxic gaseous byproducts of bipolar resection and of including intravasation of these byproducts in one's consideration of patient safety during extensive resections. Bipolar hysteroscopic resection of large leiomyomas may result in critically high carboxyhemoglobin levels, which can impair end-organ oxygen delivery with resultant ischemia; the risks of myocardial ischemia should be discussed with the anesthesia team before attempting an extensive resection. Electrocardiogram changes indicative of ischemia should prompt discontinuation of the case. Finally, carboxyhemoglobin poisoning should be included in the differential diagnosis of patients who demonstrate longer-than-expected anesthesia recovery times after bipolar resection of large submucous leiomyomas, and they should be managed with repeat evaluation of carboxyhemoglobin levels, supplemental oxygen, and cardiac monitoring.

Elevated blood carboxyhemoglobin levels as an early predictor of phototherapy requirement in moderate and late preterm infants

Objective: Preterm infants are prone to increased bilirubin burden and display adverse outcomes if left unmonitored; therefore, predicting an increased bilirubin production is of paramount importance.Methods: We aimed to evaluate carboxyhemoglobin (COHb) levels in moderate (GA: 320/7–336/7) and late preterm (GA: 340/7–366/7) infants to assess whether this molecule could be used as an early predictor of phototherapy requirement.Results: A total of 221 infants were enrolled in the study. On admission, carboxyhemoglobin levels of infants who received phototherapy were significantly higher than that of infants who did not require this treatment, and this difference persisted in the consecutive hours (median (min–max): 1.2% (0.3–1.7) versus 0.8% (0.4–1.1); p < .001). The initial and consecutive COHb levels showed positive correlation (r = 0.77, p < .001). In the post-hoc analysis, direct antiglobulin test positivity significantly affected phototherapy requirement (p < .001). Receiver operating characteristics analysis showed that a COHb level of ≥0.95% was found to have a sensitivity of 90% and a specificity of 88%. Multinomial logistic regression analysis demonstrated that high COHb levels on admission significantly increased the likelihood of phototherapy requirement when adjusted for covariants (adjusted odds ratio: 2.2; 95% confidence interval: 1.4–3.5; p < .001).Conclusion: Carboxyhemoglobin measurement can be simply used to predict preterm infants who will require phototherapy.

Use of carboxyhemoglobin as a biomarker of environmental CO exposure: critical evaluation of the literature.

Carbon monoxide (CO) poisoning is the primary cause for access to emergency department (ED) services for more than 50,000 persons in Europe and the USA every year. CO poisoning diagnosis is based on multiple factors and is usually confirmed by high carboxyhemoglobin (COHb) levels in the blood. We conducted a systematic evaluation of literature to investigate the usefulness of COHb as a biomarker of environmental CO exposure. We conducted an electronic search in Medline, Embase, and the Cochrane Library databases. We selected studies reporting high or low environmental CO concentrations, as well as COHb levels in exposed subjects presenting in ED or staying at home. We included 19 studies, but only 7 studies reported environmental CO concentration and proved a correlation between COHb and CO exposure in healthy and non-smoker subjects only. However, confounding factors were often incompletely assessed. The main symptoms reported were headache, nausea, vertigo and vomiting. COHb data stored in healthcare databases were used in six studies and provided useful information about symptoms, CO sources and patient characteristics. Most studies were classified at risk of bias. This review indicates that COHb is the most commonly used biomarker to assess CO exposure and seems to be useful. Further studies are needed to establish the reliability of COHb as a biomarker and/or explore other possible biomarkers. Surveillance systems of the general population, correlated with geographical locations and other confounding factors, could be important for CO exposure monitoring and the development of focused prevention programs.

Toxic Smoke Inhalation in Fire Victim Dogs

Fifteen dogs were found dead in a house that was on fire. Several of these dogs were partially burned. Four dogs were submitted for postmortem examination, 2 of which were determined to have died prior to the fire. Of the 2 submitted fire fatalities, only 1 dog had burns on its body (dorsum and right side of body). Internally, both dogs had soot deposits mixed with mucus in the larynx, trachea, and primary bronchi. Microscopically, soot was identified within both airways and alveolar spaces. There were no macroscopic or microscopic indications of vital heat exposure. High levels of carboxyhemoglobin were detected in the 2 dogs tested. The findings in this case support the use of postmortem examination and toxicology testing to allow for determination of vital reaction to heat and fire fumes.

Mass carbon monoxide poisoning at an ice-hockey game

A mass carbon monoxide (CO) intoxication during an ice-hockey game is described. Two hundred and thirty-five patients were seen in different hospitals, 88 of them the same night at the nearby emergency department. To evaluate long-term implications and to identify relevant indicators, a follow-up study was organized 1 year after the incident. Apart from the file data from the emergency departments, a 1-year follow-up mailing was sent to all patients. One hundred and ninety-one patients returned their questionnaire (86%). The mean age of the patients was 28 years, with 61% men. The mean carboxyhaemoglobin (COHb) was 9.9%. COHb levels were significantly higher for individuals on the ice (referee, players and maintenance personnel). There was a significant relationship with the initial presence of dizziness, fatigue and the COHb level. Headache, abdominal pain, nausea and vomiting were not significantly related to the COHb levels. The relationship between symptoms and CO level, however, should be interpreted with caution as there was a wide range between exposure and blood tests. 5.2% of patients had residual complaints, all including headache, with a significant higher incidence with high COHb levels. Only two patients had an abnormal neurological control (one slightly disturbed electroencephalography and one persistent encephalopathic complaint). Work incapacity was also significantly related to COHb levels. CO mass poisonings remain a risk in indoor sporting events. Although it causes an acute mass casualty incident, it is limited in time and delayed problems are scarce. Symptomatology is a poor tool for triage. The best prevention is the use of nonmineral energy sources such as for example electricity.

Implications of Alcohol Intoxication at the Time of Burn and Smoke Inhalation Injury

Up to 50% of burn patient fatalities have a history of alcohol use, and for those surviving to hospitalization, alcohol intoxication may increase the risk of infection and mortality. Yet, the effect of binge drinking on burn patients, specifically those with inhalation injuries, is not well described. We aimed to investigate the epidemiology and outcomes of this select patient population. In a prospective study, 53 patients with an inhalation injury and a documented blood alcohol content (BAC) were grouped as BAC negative (n = 37), BAC = 1 to 79 mg/dl (n = 4), and BAC ≥ 80 mg/dl (n = 12). Those in the last group were designated as binge drinkers according to National Institute on Alcohol Abuse and Alcoholism criteria. Binge drinkers with an inhalation injury had considerably smaller %TBSA burns than did their nondrinking counterparts (mean %TBSA 10.6 vs 24.9; P = .065) and significantly lower revised Baux scores (mean 75.9 vs 94.9; P = .030). Despite binge drinkers having smaller injuries, the groups did not differ in terms of outcomes and resource utilization. Finally, those in the binge-drinking group had considerably higher carboxyhemoglobin levels (median 5.2 vs 23.0; P = .026) than did nondrinkers. Binge drinkers with inhalation injuries surviving to hospitalization had less severe injuries than did nondrinkers, although their outcomes and burden to the healthcare infrastructure were similar to the nondrinking patients. Our findings affirm the effect of alcohol intoxication at the time of burn and smoke inhalation injury, placing renewed emphasis on injury prevention and alcohol abuse education.

Relationship between carbon monoxide intoxication and sister chromatid exchange in lymphocytes

Carbon monoxide (CO) intoxication can be serious and is reported to be the cause of more than half of all fatal intoxications. In this study, we aimed to identify its genotoxic effects based on sister chromatid exchange (SCE). CO-poisoned patients presented to the emergency services department were identified. Their demographic characteristics, vital findings, laboratory markers, source of CO gas, risk factors, and smoking habits were recorded. The genotoxic effect was assessed using the SCE method. A total of 38 patients were recruited. Their ages ranged from 16-64years (mean: 29.79±10.92years). In all the cases, the source of CO gas was a flash heater. The mean carboxyhemoglobin (COHb) level was 25.05±7.15%. Of all the patients, 12 (31.6%) had a the Glasgow Coma Scale (GCS) scores of less than 15, and an important negative correlation was found between the GCS and COHb level (r=-0.825; p<0.001). Genotoxicity investigations revealed a significantly higher SCE frequency among patients with high COHb levels compared with that of control subjects with physiological COHb levels (p<0.001). However, no correlation between increased SCE frequency and COHb level was found (r=0.16; p=0.34). CO poisoning was shown to result in genotoxicity via an increase in the frequency of SCE. This study is the first to demonstrate a genotoxic effect of CO independent of other chemicals.

Significance of the carboxyhemoglobin level for out-of-hospital cardiopulmonary arrest

Background:At low concentrations, carbon monoxide (CO) can confer cyto and tissue-protective effects, such as endogenous Heme oxygenase 1 expression, which has antioxidative, anti-inflammatory, antiproliferative, and antiapoptotic effects. The level of carboxyhemoglobin in the blood is an indicator of the endogenous production of CO and inhaled CO.Aim of study:To investigate the significance of the value of carboxyhemoglobin for out-of-hospital (OH) cardiopulmonary arrest (CPA).Materials and Methods:This study involved a medical chart review of cases treated from January to December 2005. The inclusion criteria included a patient who was transported to this department due to an OH CPA. The exclusion criteria included a patient who did not undergo blood gas analysis on arrival and who experienced CPA due to acute carbon monoxide intoxication. The subjects were divided into two groups based on their final outcome of either survival or non-survival.Results:There was no significant difference associated with the sex, age, frequency of witness collapse, bystander cardiopulmonary arrest, electrocardiogram at scene, cause of CPA, value of PCO2, HCO3-, and methemoglobin. The frequency of OH return of spontaneous circulation and the value of pH, PO2, base excess, and carboxyhemoglobin in the survival group were greater than those values in the non-survival group. There were no subjects whose carboxyhemoglobin level was 0% on arrival in the survival groups.Conclusion:There appeared to be an association between higher carboxyhemoglobin levels and survival in comparison with non-survival patients.

Mainstream smoke of the waterpipe: Does this environmental matrix reveal as significant source of toxic compounds?

In recent years the number of waterpipe smokers has increased substantially worldwide. Here we report on the concentrations of tobacco-specific nitrosamines (TSNAs) and polycyclic aromatic hydrocarbons (PAHs) in waterpipe smoke and the analysis of selected biomarkers indicative for the body burden in waterpipe users. We further identify high amounts of unburned humectants (glycerol and propylene glycol) in the waterpipe smoke as main part of the so-called “tar” fraction. These results give cause for serious concern. For standardization we applied a machine smoking protocol. Smoke was collected on glass fiber filters and analyzed for nicotine, water, humectants, TSNAs, and PAHs. In addition, we determined carbon monoxide and found high amounts in the smoke being causative for high levels of carboxyhemoglobin (COHb) in the blood of smokers. In comparison to the reference cigarette 3R4F, the nicotine contents were 10-times higher, but TSNA levels were found lower in waterpipe smoke. This finding explained the low levels of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol detected in the urine of waterpipe smokers. Finally, the levels of benzo[ a]pyrene were three times higher in waterpipe smoke compared to the reference cigarette. Altogether, the data presented in this study point to the health hazards associated with the consumption of waterpipes.