Search

Diffusion tensor imaging of the brain tissue microstructure was performed to predict or diagnose the pathophysiological mechanism underlying delayed encephalopathy after carbon monoxide poisoning and the treatment effect was analyzed. The changes in the diffusion parameters (average diffusion coefficient and fractional anisotropy) in adult patients after hyperbaric oxygen therapy of delayed encephalopathy after carbon monoxide poisoning were not significant differences of the two lateral ventricles or anterior or posterior limb of the internal capsule. In the group exposed to hyperbaric oxygen therapy, the fractional anisotropy values of the white matter in the ventricles of the brain and anterior and posterior limbs of the internal capsule were higher than those recorded before therapy, while the average diffusion coefficient values were significantly lower. These finding provide important monitoring indicators for clinicians., Competing Interests: All authors declare no conflict of interest., (© 2019 Wu et al. Published by IMR press.)

Introduction: Approximately 50,000 patients per year present at emergency departments (EDs) because of carbon monoxide (CO) intoxication. The hypothesis of this study was that the half-life of CO and the regression period of complaints could be reduced more rapidly by applying oxygen with the Continuous Positive Airway Pressure (CPAP) modality using a non-invasive mechanical ventilator., Methods: The patients were divided into Group 1 and Group 2 in terms of the treatment method applied. Patients in Group 1 received FiO2 1.0 15 l/minute oxygen at room temperature for at least 30 minutes with a non-rebreather mask. Patients in Group 2 received FiO2 1.0 oxygen at 12 cmH2O pressure with non-invasive mechanical ventilation for at least 30 minutes with an oronasal mask in the CPAP modality., Results: The median values (interquartile range) of carboxyhemoglobin (COHb) levels at zero and 30 minutes of patients were 19% (8) and 14% (6) in Group 1 and 22% (8) and nine percent (3) in Group 2; a median difference of six percent (2) was detected in Group 1 and of 13% (4) in Group 2 in the first 30 minutes (P <.001). When the symptoms of the patients were examined, the median values of Group 1 and Group 2 at zero minutes were both eight units and at 30 minutes were five and three units, respectively. A decrease of five units was determined in the median of Group 2 in the first 30 minutes, and a decrease of two units in the median of Group 1 (P <.001)., Conclusion: The use of CPAP was determined to more rapidly reduce COHb level as opposed to high-flow oxygen therapy. It is also thought that it may enable earlier discharge by reducing the duration of the emergency follow-up since it provides a faster improvement in the symptoms of the patients.

Objectives: To identify the risk factors related to the prognosis of carbon monoxide (CO)-poisoned patients in the hospital., Design: Retrospective observational study., Setting: Tri-Service General Hospital, Taiwan., Methods: We conducted a review of the medical records of 669 CO-poisoned patients, who were admitted to the Department of Emergency, Tri-Service General Hospital, Taiwan, from 2009 to 2014. Demographic, clinical and laboratory data were collected for analysis. In the study, the end points for poor outcome were patients who either still had sequelae, were bedridden or died after treatment. The independent t-test, χ 2 test and binary logistic regression were used to identify the association between the prognostic factors and the outcomes., Results: The logistic regression analysis confirmed that the Glasgow Coma Scale (GCS) score (p=0.008) and blood urea nitrogen (BUN) (p=0.002) were related to poor outcomes. Furthermore, the receiver operating characteristic (ROC) curve showed that the cut-off point of intubation days was 1.5 days (area under the ROC curve [AUC]=0.793) for all patients and 2.5 days (AUC=0.817) for patients with intubation when predicting poor outcomes., Conclusion: We identified the factors that most strongly predict the prognosis of CO poisoning, including the GCS score, serum BUN and intubation days. Moreover, the number of hyperbaric oxygen treatments seems to have impact of the outcome., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2019. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Objective: In this study, we aimed to investigate oxidative stress and antioxidant parameter levels in patients with carbon monoxide (CO) poisoning., Methods: The study was conducted prospectively between March 1, 2015 and April 30, 2016 in the pediatric emergency department. Eligible patients included children aged 0-18 years old with a diagnosis of CO poisoning. To determination of oxidative stress and antioxidant parameter levels, venous blood with heparinized and urine samples were drawn during the admission and after normobaric oxygen (NBO) and hyperbaric oxygen (HBO) treatment., Results: Forty-seven children with CO poisoning for study group and 29 patients as control group were included to the study. Sixteen patients treated with HBO. Basal plasma malondialdehyde levels were found to be significantly higher in the CO poisoning group when compared with the control group ( p = 0.019). There is no significant difference in oxidative stress and antioxidant parameter levels except erythrocyte catalase enzyme levels in patients treated with NBO when comparing before and after NBO treatment ( p > 0.05). Decreasing of basal erythrocyte catalase enzyme levels were found statistically significant after NBO treatment ( p = 0.04). There was no significant difference in oxidative stress and antioxidant parameter levels in patients treated with HBO before and after therapy ( p > 0.05)., Conclusions: CO poisoning is associated with increased lipid peroxidation in children immediately after the poisoning. However, both treatment modalities including NBO or HBO do not have a significant effect on oxidative stress or antioxidant parameter levels.

BACKGROUND Hyperbaric oxygen (HBO) is used in patients with carbon monoxide (CO) poisoning to prevent the occurrence of delayed neurological sequelae. However, inconsistent results were obtained regarding the treatment effects of HBO. Therefore, the current meta-analysis was conducted based on published randomized controlled trials (RCTs) to determine the effect of HBO on neurologic sequelae and all-cause mortality in patients with CO poisoning. MATERIAL AND METHODS Electronic databases MedLine, EmBase, and the Cochrane Library were searched for relevant RCTs from inception to March 1, 2019. The pooled relative risks (RRs) and weighted mean differences (WMDs) with corresponding 95% confidence intervals (CIs) were calculated to evaluate the outcomes by using a random-effects model. Sensitivity, subgroup, and publication bias analyses were also conducted. RESULTS Seven RCTs, including 9 cohorts and a total of 2023 patients with CO poisoning, were enrolled in this study. The summary results revealed that HBO showed an association with lower risk of memory impairment compared to patients receiving normobaric oxygen (NBO), whereas 2 sessions of HBO showed an association with higher risk of memory impairment compared to those who received 1 session of HBO. Moreover, HBO was associated with increased neuropsychologic scores of block design and trail making when compared with NBO. No other significant differences regarding the treatment effects of HBO were observed. CONCLUSIONS These results indicate that HBO therapy significantly reduces the risk of memory impairment compared to NBO, but 2 sessions of HBO might not be better for memory impairment than 1 session of HBO.

Inhaled carbon monoxide (CO) displaces oxygen from hemoglobin, reducing the capacity of blood to carry oxygen. Current treatments for CO-poisoned patients involve administration of 100% oxygen; however, when CO poisoning is associated with acute lung injury secondary to smoke inhalation, burns, or trauma, breathing 100% oxygen may be ineffective. Visible light dissociates CO from hemoglobin. We hypothesized that the exposure of blood to visible light while passing through a membrane oxygenator would increase the rate of CO elimination in vivo. We developed a membrane oxygenator with optimal characteristics to facilitate exposure of blood to visible light and tested the device in a rat model of CO poisoning, with or without concomitant lung injury. Compared to ventilation with 100% oxygen, the addition of extracorporeal removal of CO with phototherapy (ECCOR-P) doubled the rate of CO elimination in CO-poisoned rats with normal lungs. In CO-poisoned rats with acute lung injury, treatment with ECCOR-P increased the rate of CO removal by threefold compared to ventilation with 100% oxygen alone and was associated with improved survival. Further development and adaptation of this extracorporeal CO photo-removal device for clinical use may provide additional benefits for CO-poisoned patients, especially for those with concurrent acute lung injury., (Copyright © 2019 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.)

Objectives: To describe health care quality indicators in cases of carbon monoxide (CO) exposure attended by prehospital services and to explore factors associated with the use of pulse CO-oximetry (SpCO) for the noninvasive estimation of CO saturation of arterial blood., Material and Methods: Cohort study of patients exposed to CO and transported by advanced life support units of the Emergency Medical Services of Catalonia between January 2015 and December 2017. We selected 11 applicable quality indicators and used multivariate analysis to explore factors associated with the recording of SpCO., Results: We studied 1676 cases of CO exposure. SpCO was recorded in 1108 cases (66.1%). CO saturation exceeded 10% in 358 patients (32.3%). Adherence was deficient in 5 of the 11 applicable quality indicators. Multivariate analysis showed less use of pulse CO-oximetry when another toxic exposure was present (odds ratio [OR], 0.34; 95% CI, 0.11- 1.00) and when the first responder was from the advanced life support service (OR, 0.43; 95% CI, 0.31-0.59). SpCO was used more in the presence of a history of mental health problems (OR, 3.01; 95% CI,1.27-7.17), headache (OR, 2.13; 95% CI, 1.2-3.72), and along with use of oxygen therapy (OR, 10.33; 95% CI, 5.46-19.53)., Conclusion: Prehospital attendance of episodes of CO exposure is marked by failure to comply with some health care quality indicators. We detected factors associated with under use of SpCO as well as areas to target for improvement.

Background and Objectives: Carbon monoxide is one of the most common causes of fatal intoxications in the United States, and multiple previous studies have demonstrated that cigarette smokers have higher levels of carbon monoxide in their blood. However, the potential negative effects due to acute carbon monoxide poisoning from excessive cigarette smoking have not been well established., Methods: This is a single patient case report., Results: In this case report, a 40-year-old male with a past medical history of depression, anxiety, panic attacks, and substance use disorder developed symptomatic, acute carbon monoxide poisoning secondary to heavy cigarette smoking in a confined space. In this patient, the cessation of clonazepam therapy coincided with increasing anxiety and panic disorder with agoraphobia triggering an escalation in his cigarette smoking. The patient smoked three packs of cigarettes in 3 hours and developed worsening of his symptoms. He required inpatient treatment with benzodiazepines and hyperbaric oxygen., Discussion and Conclusions: Therefore, it is important to recognize cigarette smoke as a significant source of carbon monoxide exposure., Scientific Significance: While the negative effects of cigarette smoking are often perceived as being chronic and only coming to fruition after numerous years of exposure, it is important for both physicians and patients to recognize the possibility for potentially life-threatening acute toxicity secondary to carbon monoxide exposure. (Am J Addict 2019;28:413-415)., (© 2019 American Academy of Addiction Psychiatry.)

Oxygen is the main treatment of carbon monoxide (CO) poisoning. In two simultaneous cases, the efficacy of conventional and continuous positive airway pressure (CPAP)-administered oxygen therapy was compared. A 63-year-old man and his 58-year-old wife were brought to the emergency department with complaints of dizziness, headache, and nausea. The man had a history of congestive heart failure and additionally had shortness of breath. Initial carboxyhemoglobin (COHb) values were 26% in the male patient and 24% in his wife. For the female patient, oxygen therapy was performed with a reservoir balloon mask; a CPAP device was used for the male patient. The COHb levels decreased below five percent after approximately two hours in the male patient and at the end of five hours in his wife. In follow-up, symptomatic relief was achieved in both patients and no additional complications were observed. According to our experience, CPAP ventilation can be a new and effective method for oxygen therapy in CO poisoning.

Objective: Carbon monoxide is produced by the incomplete combustion of organic fuel. In the United States, it is responsible for about 500 deaths annually. Increased carboxyhemoglobin concentration and hypoxia disrupt cardiac myocyte integrity and cause dysrhythmias, acute cardiac failure and coronary artery disease. We described a case of a patient with CO-poisoning and ST elevation at ECG precordial leads who developed severe transient heart failure., Case Presentation: A 57-year-old man was admitted to the emergency department for acute carbon monoxide poisoning that led to respiratory and cardiac failure. The electrocardiogram showed ST elevation in precordial leads, but the coronary angiography was normal. The patient was successfully treated and discharged. Three days later he was readmitted for similar symptoms and subsequently died. We hypothesize that the ECG findings were related to transient coronary vasospasm due to CO poisoning and that acute respiratory and cardiac failure related to carbon monoxide toxicity caused death., Conclusions: The management of patients poisoned by carbon monoxide requires early identification and intensive treatment and a careful evaluation of the home environment prior to discharge. ST elevation in such patients may be related to coronary vasospasm.

Background: Acute carbon monoxide poisoning is a common environmental emergency worldwide. Treatment options are limited to normobaric oxygen therapy with a nonrebreather face mask or endotracheal tube and hyperbaric oxygen. The aim of this study is to determine the half-life of carboxyhemoglobin (COHb) in adult patients admitted to the emergency department with acute carbon monoxide poisoning receiving high flow nasal cannula (HFNC) oxygen. Device tolerability and patient comfort with the high flow nasal cannula were also evaluated. Methods: This study was conducted between January 2017 and February 2018 in two academic emergency departments. Venous blood samples were obtained at 10 minute intervals to determine the rate of elimination of COHb. Patient comfort was evaluated by a verbal numeric rating scale. The primary outcome was the determination of the half-life of COHb. The secondary outcome was device tolerability and patient comfort with the high flow nasal cannula oxygen delivery system. Results: A total of 33 patients were enrolled in the study. The mean baseline COHb level of the patients was 22.5% (SD 8%). The mean half-life of carboxyhemoglobin was determined as 36.8 minutes (SD 9.26 min) with high flow nasal cannula oxygen. COHb levels were halved during the first 40 minutes in 22 (67%) of the study patients. Twenty of the patients receiving HFNC oxygen did not report intolerance or discomfort. Among the 11 patients who requested a change in the flow rate, the median verbal numeric rating score was 7. After decreasing the flow rate, the median verbal numeric rating score was 9. Conclusion: High flow nasal cannula oxygen is an easy, safe, comfortable and effective method to reduce COHb. HFNC may be a promising alternative method if it is validated as effective in future studies with clinical outcomes.

Hyperbaric oxygen therapies may have grown out of emergencies such as those for Decompression Sickness (DCS), but more commonly in the U.S., hyperbaric oxygen is used for much more elective problems. Wound healing applications lead this trend. Nationally many more hyperbaric centers exist to treat elective problems adjunctively, and this is a concise review of these indications as well as pointing out where even elective centers might be able to broaden their practices.

Objective: Extracorporeal membrane oxygenation (ECMO) has been widely used to stabilize patients with impairment of cardiac/respiratory function, and ECMO has been used to stabilize cardiopulmonary insufficiency caused by carbon monoxide (CO) poisoning in a porcine model. Airborne transportation in fixed wing aircraft of patients suffering from CO poisoning is challenging because as the air pressure drops, the oxygen content falls correspondingly. The aim of this study was to show the feasibility of cannulating and establishing ECMO therapy during airborne transportation after severe CO poisoning in a porcine model., Methods: An anesthetized pig was subjected to severe CO poisoning and loaded onto a Hercules aircraft. Cardiac arrest was induced at an altitude of 8,000 feet, after which cannulation and the establishment of venoarterial (VA) ECMO were performed. Vital signs were monitored, and arterial blood samples were analyzed while airborne., Results: CO poisoning was induced with carboxyhemoglobin at 58% before takeoff. We successfully cannulated the animal in-flight during cardiac arrest and initiated VA ECMO. The animal regained spontaneous circulation and was successfully weaned from ECMO. During VA ECMO, PaO 2 was maintained at high levels (420-615 mm Hg)., Conclusion: It is possible to cannulate and initiate VA ECMO treatment as airborne en route therapy for cardiac arrest and severe CO intoxication in a porcine model., (Copyright © 2019 Air Medical Journal Associates. Published by Elsevier Inc. All rights reserved.)

Introduction: Waterpipe (hookah) smoking is popular; in Dutch surveys, 26% of the respondents have smoked a waterpipe at least once. However, waterpipe smoking is not without risk. We present a series of carbon monoxide (CO) poisonings after waterpipe smoking and discuss the etiology and treatment of CO intoxication after waterpipe smoking., Case Descriptions: We present three patients who presented with syncopial episodes and a variety of other neurological and circulatory symptoms after smoking a waterpipe. All patients had significantly elevated carboxyhaemoglobin levels (26%, 19% and 26%). Patients were treated with oxygen, following Dutch guidelines; one patient was admitted for eight hours of oxygen therapy. The other two patients were observed shortly, diverging from the guidelines because symptoms passed and the carboxyhaemoglobin normalised., Discussion: Reviewing combustion chemistry, the formation of CO is a logical consequence of using burning coals as a heat source. This is due to CO2 reduction with carbon. This chemical process has not previously been related to waterpipe smoking. Dutch guidelines advise eight hours of oxygen therapy. The research this guideline is based on, justifies therapy directed at symptom relief and carboxyhaemoglobin normalisation. This strategy may prevent unnecessary hospital admissions and exposure to high-dose oxygen., Conclusion: We described three cases of CO intoxication after waterpipe smoking and argue why this may not be an incidental finding. Greater awareness of this risk is urgently needed. We conclude that the literature does not firmly support a fixed treatment duration.

Rationale: Acute kidney injury (AKI), rhabdomyolysis, and delayed leukoencephalopathy after carbon monoxide (CO) poisoning are very rare. We report a case presenting with AKI, rhabdomyolysis, and delayed leukoencephalopathy after CO poisoning., Patient Concerns: The patient was admitted to our emergency department due to loss of consciousness after CO exposure during a suicide attempt., Diagnoses: Laboratory findings revealed elevated carboxyhemoglobin, serum creatinine, and serum muscle enzyme levels. Initially, this patient was diagnosed with AKI and rhabdomyolysis due to CO poisoning. A month after the CO poisoning, she showed neuropsychiatric symptoms. Brain magnetic resonance imaging showed white-matter hyperintensity on the T2 flair image. Therefore, she was diagnosed with delayed leukoencephalopathy after CO poisoning., Interventions: At the same time as diagnosis of AKI and rhabdomyolysis, the normobaric oxygen and hydration therapies were performed. A month later, rehabilitation was started due to delayed leukoencephalopathy., Outcomes: Her renal function and muscle enzyme levels were completely restored with alert mental status. She could walk with the aid of a walker at last visit., Lessons: This case shows that we should consider about rare acute and late complications such as AKI, rhabdomyolysis, and delayed leukoencephalopathy after CO poisoning.

Carbon monoxide (CO) is a toxic, color-, taste- and odorless gas with fatal consequences if undetected. Intoxication caused by CO is frequent possibly leading to a high morbidity and mortality. The disease involves multiple organ systems without a typical clinical presentation. The clinical picture is furthermore unrelated to levels of carboxyhemoglobin - the routine biomarker. Therefore the diagnosis and treatment can be very demanding. This article in detail reviews epidemiology, symptoms, diagnosis and the therapy of this multidisciplinary challenge., (Copyright © 2018 Elsevier Ltd and ISBI. All rights reserved.)

Background: The symptoms of acute carbon monoxide (CO) poisoning are unspecific, ranging from headaches to unconsciousness and death. In addition to acute symptoms, delayed severe neurological sequelae may occur. While a total of 440 deaths by CO poisoning were registered in Germany in 1999, a total of 594 patients died (0.73 per 100,000 inhabitants) in 2014 and in 2015 the number even increased to 648 deaths. A national database on clinical symptoms, course of illness or quality of care concerning CO poisoning does not yet exist., Methods: The treatment data of patients admitted to the Hyperbaric Emergency Centre Wiesbaden (HEC) from 2013 to 2017 with CO poisoning formed the basis of the study. This was a comparative evaluation of patient demographics, poisoning sources, symptom spectrum, course of treatment and time intervals registered on the preclinical and clinical levels., Results: From 2013 to 2017 a total of 476 patients (282 men and 194 women) with an average non-invasively measured CO-Hb of 15% (Q 0.25  = 7.6%, Q 0.75  = 22.3%) were treated with hyperbaric oxygen. Heaters (n = 131), charcoal barbecues (n = 93), fires (n = 90), hookahs (n = 78) and combustion engines (n = 37) were the most frequent CO sources identified. Headaches, vertigo, nausea and syncope were the most prevalent symptoms. A median of 91 min (Q 0.25  = 53 min; Q 0.75  = 147 min) passed between first medical contact and BGA-validated diagnosis. In total, 151 patients were transferred directly to the HEC, whereas 325 patients were secondarily transferred. The delay in this subgroup took 183 min (median Q 0.25  = 138 min; Q 0.75  = 248 min). After receiving the first hyperbaric treatment, 80% were free of symptoms. Remaining symptoms included headache (10%), fatigue (8%), vertigo (5%) and nausea (3%) and 45 patients terminated further treatment. Of the patients 417 received a second hyperbaric treatment and 370 patients were treated 3 times. After the third treatment, 89% were free of symptoms and 5% still reported headaches, 3% vertigo and 2% fatigue. In total, 6 patients died and 430 patients were symptom-free after treatment., Conclusion: Commonly known sources (fire, charcoal grills) aside, many poisonings by smoking a hookah were observed. This study highlights the importance of considering CO poisoning as a differential diagnosis when encountering patients, especially of younger age, with non-specific neurological symptoms, as well as the importance of early initiation of treatment. A direct correlation between CO-Hb values (whether measured noninvasively or by invasive BGA) and the initial symptoms could not be demonstrated. In total, substantial time expired between the diagnosis and start of treatment of patients transported to a primary care hospital compared to those transported directly to the HEC. Although analysis showed adequate treatment with oxygen in the preclinical interval, administration of oxygen during primary hospital stay showed room for improvement. Introducing a national CO poisoning register and uniform treatment guidelines could improve in-house clinical processes. Multicenter studies are needed to close the gaps identified in the quality of care in Germany.

Rationale: Carbon monoxide (CO) poisoning can cause severe damage to the nervous system, and can also cause serious damage to organs, such as the heart, kidneys, and lungs. CO damage to myocardial cells has been previously reported. This can lead to serious complications, such as myocardial infarction., Patient Concerns: A 47-year-old female patient complained of sudden chest pain for 30 minutes. Before admission, the patient had non-radiating burning chest pain after inhalation of soot., Diagnosis: An electrocardiogram showed that myocardial ischemia was progressively aggravated, manifested by progressive ST-segment elevation, and accompanied by T wave inversion and other changes. No obvious coronary stenosis was observed in a coronary angiographic examination. Therefore, the patient was considered to have developed variant angina resulting from CO poisoning-induced coronary artery spasm., Interventions: The patient was treated with drugs for improving blood circulation and preventing thrombosis, and underwent hyperbaric oxygen therapy., Outcomes: Clinical symptoms relieved after the treatment., Lessons: Findings from this case suggest that CO can cause coronary artery spasm and it is one of the predisposing factors of variant angina. For these patients, hyperbaric oxygen therapy can improve blood circulation and prevent formation of thrombus and encephalopathy.

Background: Carbon monoxide (CO), a colorless and odorless gas, is one of the common causes of poisoning-related deaths worldwide. CO poisoning can result in hypoxic brain damage and death, but intensive care can improve the likely outcome for critically ill patients. However, there is a paucity of clinical data regarding the prognostic factors and association between organ dysfunction and clinical outcome of patients treated for CO poisoning in the intensive care unit (ICU)., Methods: We performed a retrospective study of patients admitted to a university affiliated hospital ICU between July 2001 and December 2010 following CO poisoning. Outcomes were survival to ICU discharge and to hospital discharge., Results: Seven hundred and eighty-seven patients were admitted to the university hospital following CO poisoning, of which 140 (17.8%) were admitted to the hospital ICU. The overall mortality rate of the patients admitted to the ICU was 14.3% (20/140). Univariate analysis indicated that non-surviving patients with CO poisoning were more likely to have initial blood carboxyhemoglobin (COHb) level > 30%, shock, acute respiratory failure, Acute Physiology and Chronic Health Evaluation II (APACHE II) score ≥ 25, Glasgow coma scale (GCS) score of 3, acute renal failure, dysfunction or failure of more than 3 organs, low blood pH, low HCO3- level, high potassium level, and high glucose level. They were also more likely to have not received hyperbaric oxygen (HBO) intervention. Multivariate logistical regression analysis indicated that the mortality rate of patients treated in the ICU for CO poisoning was higher if their initial APACHE II score was ≥25, GCS was 3, and more than 3 organs were dysfunctional. Moreover, HBO intervention in ICU significantly decreased patients' risk of mortality due to CO poisoning., Conclusion: In conclusion, we observed that APACHE II score >25, GCS 3, and dysfunction of more than 3 organ systems on admission to emergency department was associated with a significant mortality risk in patients treated in the ICU for CO poisoning. Moreover, HBO therapy could reduce the risk of mortality in patients with CO poisoning in ICU., (Copyright © 2018. Published by Elsevier B.V.)

In The Boston Medical and Surgical Journal of 1847 (later to be called The New England Journal of Medicine), Boston chemist George Washington Frost Mellen claimed that inhaled nitrous oxide gas supports human life in the manner of oxygen gas, and he proposed the use of nitrous oxide in resuscitation from drowning and from carbon monoxide poisoning. The claim was reprinted in at least one dental journal and was long cited as justification for the use of 100% nitrous oxide for inhaled anesthesia. Advocates included anesthesia pioneer and painless dentist Gardner Quincy Colton. Though misguided as to nitrous oxide, Mellen was a prominent member of the Boston community for the abolition of slavery., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Rationale: Acute myocardial infarction is a rare complication of carbon monoxide poisoning. there is often no chest pain and other typical manifestations. We report a patient with mild carbon monoxide poisoning who had acute dyspnea as the earliest symptom and was later diagnosed with non-ST elevation myocardial infarction (NSTEMI) and acute left heart failure., Patient Concerns: A 73-year-old woman complained of dizziness and fatigue with shortness of breath after carbon monoxide intoxication., Diagnoses: This patient had a clear history of carbon monoxide poisoning, acute respiratory distress, bilateral lung dry and moist rale, chest X-ray showed bilateral pulmonary edema, Electrocardiograph indicated general depression of the ST segment of the leads in the chest, cardiac troponin I (CTNI) increased progressively, cardiac ultrasonography indicated abnormal ventricular wall movement, coronary angiography suggested left main trunk and 3-vessel lesions, suggesting diagnosis acute carbon monoxide poisoning, acute coronary syndrome, acute left heart failure., Interventions: She was treated with a high concentration of oxygen, an inhibitor of platelet aggregation (aspirin plus clopidogrel), an anticoagulant (low molecular weight heparin), an antimicrobial (ceftizoxime), an expectorant (mucosolvan), diuresis (furosemide and spironolactone), and myocardial support (Metoprolol). Coronary angiography and stent placement were performed 8 days later., Outcome: On the 10th day after onset of the condition, echocardiography was performed, which showed that cardiac function was improved. Mild segmental wall motion abnormality was observed on echocardiography. After 14 days, the patient had recovered well and was discharged without chest tightness, chest pain, dizziness, headache, or unresponsiveness., Lessons: This case suggests that the symptoms of carbon monoxide poisoning are complex and diverse. It can be manifested as a primary hypoxic symptom, or cause the exacerbation of underlying diseases due to hypoxia. Therefore, patients with carbon monoxide poisoning should actively seek comprehensive cardiac examination to ensure early diagnosis. Whenever necessary, coronary angiography and stent implantation should be performed to improve the likelihood of the patient's survival.

Purpose: Hyperbaric medicine is nascent in Korea when compared to other developed countries, such as the United States and Japan. Our facility has been managed by physicians with certifications from the Undersea and Hyperbaric Medical Society (UHMS) and National Oceanic and Atmospheric Administration in diving and clinical diseases since October 2016. This study was conducted to share similar issues that are encountered during the establishment of a program in a new area through our experiences in the operation of a hyperbaric oxygen (HBO2) therapy center., Methods: In this retrospective observational study we collected data on HBO2 patients treated at our center between October 2016 and June 2018 after HBO2 was conducted by HBO2-certified physicians. We then compared demographic data of patients with data from January 2011 to September 2015 - before HBO2 operations were conducted by HBO2-certified physicians., Result: A total of 692 patients received 5,130 treatments. Twelve indicated diseases were treated using HBO2 therapy. Fifty-six critically ill patients with intubation received HBO2. Although two patients experienced seizure due to oxygen toxicity during the study period, certified physicians and inside attendant took immediate corrective action., Conclusion: After the establishment of the HBO2 center operated by physicians with certification, more patients, including critically ill patients, received HBO2 safely for various diseases. In order to improve the practice of hyperbaric medicine in Korea, the Korean Academy of Undersea and Hyperbaric Medicine (KAUHM), an advanced and well-organized academic society, should communicate often with HBO2 centers, with the aim to set Korean education programs at UHMS course levels and increase reimbursement for HBO2 therapy., Competing Interests: The authors of this paper declare no conflicts of interest exist with this submission., (Copyright© Undersea and Hyperbaric Medical Society.)

Objective: Carbon monoxide poisoning (COP) is the leading cause of mortality and morbidity due to poisoning worldwide. Because children are affected more quick and severely from COP, they may require a longer treatment period, even if carboxyhemoglobin (CO-Hb) and/or lactate levels return to normal. Therefore, a new marker that predicts the duration of treatment and the final outcomes of COP is needed., Methods: This case control study was conducted on 32 carbon monoxide-poisoned patients younger than 18 years who had been admitted to pediatric emergency department. The control group included age- and sex-matched 30 healthy children. Blood samples were obtained for analysis of arterial blood gases, CO-Hb percent, methemoglobine, lactate, and asymmetric dimethylarginine (ADMA)., Results: Asymmetric dimethylarginine levels were significantly increased (P < 0.05) in patients with COP on admission and after the treatment when compared with controls (1.36 [0.89-6.94], 1.69 [0.76-7.81], 1.21 [0.73-3.18] nmol/L, respectively). There was no positive correlation between CO-Hb and ADMA levels on admission and at 6 hours (P = 0.903, r = 0.218, P = 0.231, r = 0.022, respectively). Positive correlation was found between lactate and CO-Hb levels on admission (P = 0.018, r = 0.423)., Conclusions: This study showed that ADMA levels were still high after 6 hours of 100% oxygen therapy in children with COP, even CO-Hb and/or lactate levels return to normal range. On the basis of these results, we consider that ADMA may be a useful biomarker in patient with COP.

Background: Carbon monoxide poisoning (COP) is the most common cause for poisoning by inhalation in Germany. In the past 8 years, a marked increase in the number of COP-related deaths has been registered nationwide. A national German guideline is missing., Methods: The national and international literature was screened systematically. Existing international guidelines and expert recommendations for the diagnosis and treatment of COP were compared and evaluated. Furthermore, quality of health care was analyzed by a prospective preclinical dataset of emergency rescue services and retrospective analysis of routine data from 2014 to 2016 in Germany., Results: There is not a single evidence-based guideline worldwide. We determined 8 key performance indicators based on the five recommendations available for treatment of COP. These indices were subdivided into prehospital terms, hospital facilities, and diagnostic and therapeutic measures performed; they act as indicators for quality of care. In particular, the key figure "start oxygen" revealed that up to 41 % of the patients had not been treated with inhaled oxygen. In summary, data capture showed considerable incompleteness that is mainly due to missing time stamps., Conclusion: In order to achieve a consistent treatment of patients with COP which meets the standard of recommended care, there is an urgent need for a consented national guideline. Another objective is to establish a nationwide prospective registry evaluating the treatment of carbon monoxide poisoning., (Copyright © 2018. Published by Elsevier GmbH.)

Objective: The Florida Department of Health in Miami-Dade County (DOH-Miami-Dade) investigated 106 reported carbon monoxide (CO) exposures over a 9-day timeframe after Hurricane Irma. This report evaluates risk factors for CO poisoning and the importance of heightened surveillance following natural disasters., Methods: Data on CO poisoning cases from September 9 to 18, 2017 were extracted from Merlin, the Florida Department of Health Surveillance System. Medical records were obtained and follow-up interviews were conducted to collect data on the confirmed CO poisoning cases. Data were analyzed using SAS v9.4., Results: Ninety-one of the 106 people exposed to CO met the case definition for CO poisoning: 64 confirmed, 7 probable, and 20 suspect cases. Eighty-eight percent of the affected individuals were evaluated in emergency departments and 11.7% received hyperbaric oxygen treatment. The most frequently reported symptoms included headache (53.3%), dizziness (50.7%), and nausea (46.7%). Three patients expired due to their exposure to CO., Conclusions: Post Hurricane Irma, the DOH-Miami-Dade investigated numerous cases for CO exposure. By understanding who is most likely to be impacted by CO and the impact of generators' location on people's health, education efforts can be tailored to the population most at risk and further CO exposures and related mortalities following natural disasters can be reduced. (Disaster Med Public Health Preparedness. 2019;13:94-96).

BACKGROUND High-flow nasal cannula (HFNC) is an alternative to conventional normobaric oxygen therapy (NBO) for hypoxemic patients. Since nothing is known about its effect on carbon monoxide (CO) poisoning, we hypothesized that HFNC might be a useful device in the treatment of CO poisoning victims. MATERIAL AND METHODS We retrospectively reviewed the medical records of patients who were admitted consecutively to the emergency department with CO intoxication. Patients were divided into 2 groups: patients treated with HFNC and patients treated with conventional face mask (CFM). Demographic data, pretreatment, and control (after 1 hour) arterial blood gas analyses values of the patients were evaluated. RESULTS Sixty-eight patients (mean age 35.8±18.7 years) were included in this study. NBO was given via HFNC to 38 patients (55.9%), and via CFM to 30 patients (44.1%). The demographic characteristics and pretreatment values of carboxy-hemoglobin (COHb) were similar in the 2 groups. The mean COHb value of the HFNC group at the first hour was found significantly lower than the CFM group: 9.5±4.7 and 12.0±5.1, respectively (P=0.041). Improvement of COHb level was significantly higher in the HFNC group compared to the CFM group: 12.5±4.5 versus 6.7±3.7, respectively (P=0.001). CONCLUSIONS HFNC was superior than CFM in alleviating COHb levels in the victims of CO poisoning. We believe that using HFNC will increase patient comfort by shortening the duration of treatment in emergency department settings, especially in patients who have mild clinical findings of CO poisoning.

Introduction: Carbon monoxide (CO) poisoning is frequent worldwide but knowledge regarding the epidemiology is insufficient. The aim of this study was to clarify the extent of this intoxication, its mortality and factors associated with mortality., Materials and Methods: National databases from Statistics Denmark were used to identify individuals who suffered from CO-poisoning during 1995-2015, as well as information regarding co-morbidities, mortality and manner of death., Results: During the period from 1995 to 2015, 22,930 patients suffered from CO-poisoning in Denmark, and 21,138 of these patients (92%) were hospitalized. A total of 2,102 patients died within the first 30 days after poisoning (9.2%). Among these, 1,792 (85% of 2,102) were declared dead at the scene and 310 (15% of 2,102) died during hospitalization. Deaths due to CO-poisoning from smoke were intentional in 6.3% of cases, whereas deaths due to CO containing gases were intentional in 98.0% of cases. Among patients who survived >30 days, there was no significant difference in survival when comparing hyperbaric oxygen therapy (HBO) treatment with no HBO treatment after adjustment for age and co-morbidities such as drug abuse, psychiatric disease, stroke, alcohol abuse, arterial embolism, chronic obstructive pulmonary disease, cerebrovascular disease and atrial fibrillation. Several co-morbidities predicted poorer outcomes for patients who survived the initial 30 days., Conclusions: Poisoning from smoke and/or CO is a frequent incident in Denmark accounting for numerous contacts with hospitals and deaths. Both intoxication and mortality are highly associated with co-morbidities interfering with cognitive and physical function. Treatment with HBO was not seen to have an effect on survival., Competing Interests: The authors have declared that no competing interests exist.

Objectives: Delayed neuropsychiatric sequelae (DNS) are serious complications of carbon monoxide poisoning; neuropsychiatric disorders can occur within a few days of recovery from acute poisoning. Hyperbaric oxygen therapy (HBOT) has been the main treatment of carbon monoxide (CO) poisoning and was recommended as the treatment choice for CO poisoning by the American Undersea and Hyperbaric Medical Society and the Tenth European Consensus Conference on Hyperbaric Medicine of the European Underwater and Baromedical Society. However, the optimal timing for commencing HBOT in patients with CO poisoning remains unknown. We therefore conducted a retrospective study in an attempt to target the optimal time of HBOT for DNS prevention., Methods: A retrospective review of patient files/medical records was conducted on all patients with CO poisoning admitted to the Emergency Department of Linkou Chang-Gung Memorial Hospital, Taiwan between January 1, 2009 and December 31, 2015. A total of 279 patients who received HBOT were eligible for further DNS detection. DNS was defined as the presence of one of the following neurological, cognitive, or psychological sequelae that were documented in the medical record during hospital stay or outpatient clinic follow-up for at least 6 months. A multivariable logistic regression analysis was employed to identify potential determinants of DNS after receiving HBOT for CO poisoning. A receiver operating characteristic (ROC) curve was used to analyse the influence of duration from CO exposure to HBOT on DNS development., Results: A Glasgow coma score of <9 (odds ratio [OR], 3.20; 95% confidence interval [CI], 1.19-8.60) and a longer duration from CO exposure to HBOT (OR, 1.06; 95% CI, 1.03-1.09) were associated with a higher risk of DNS. By contrast, the presence of multiple victims from the same incident was associated with a lower risk of DNS. The ROC curve for the duration between CO exposure and HBOT in predicting DNS development demonstrated an area under the curve of 0.638 (95% CI, 0.575-0.698). The optimal cut-off point according to the Youden index was 22.5 h, with a sensitivity of 41.7% and a specificity of 85.9%. We also stratified the duration from CO exposure to HBOT into 5 intervals (< 6 h, 6-11 h, 12-23 h, 24-47 h and ≥ 48 h) and revealed a trend of increasing DNS risk with time., Conclusions: We identified several potential predictors of DNS in patients with CO poisoning who received HBOT. Multivariable logistic regressions further revealed that longer duration from CO exposure to HBOT, loss of consciousness, and the presence of multiple victims were independent predictors of DNS development. HBOT should be performed as early as possible and preferably within 22.5 h after CO poisoning., (Copyright © 2018 Elsevier B.V. All rights reserved.)

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.

Shisha smoking has spread to many countries since the 1990s and is now a global phenomenon among adolescents. Notwithstanding the connotations of conviviality of shisha smoking, it is in fact highly dangerous since the smoke inhaled contains toxic substances. Carbon monoxide (CO) poisoning carries a high risk of neurological and neuropsychological sequelae such as memory loss, impaired concentration, mood disorders, and various other symptoms. We report a case of severe CO poisoning in a 13-year-old boy after smoking shisha that caused loss of consciousness and seizure. To our knowledge, there have as yet been no reports of cases involving children. We present some epidemiological data on shisha smoking in adolescents as well as on CO intoxication., (Copyright © 2018 Elsevier Masson SAS. All rights reserved.)

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.

Background: Severe intoxication with carbon monoxide (CO) is extremely lethal and causes numerous deaths due to cardiac or respiratory failure. Conventional intensive treatment may not be sufficient. The aim of this study was to investigate the treatment effect of extracorporeal veno-arterial extracorporeal membrane oxygenation (ECMO) following severe CO poisoning in an experimental porcine model., Methods: A total of twelve pigs were anaesthetized, routinely monitored and intoxicated by inhalation of CO until the beginning of cardiac failure and randomized to a treatment (ventilator using an FiO 2 of 100% or ECMO). In the case of cardiac arrest, advanced resuscitation using standard guidelines was performed for at least 10 min. ECMO was also initiated in the ventilation group if the return of spontaneous circulation did not occur within 10 min. Lung tissue biopsies were obtained before and after CO intoxication., Results: All animals in the ECMO group survived; however, one had to be resuscitated due to cardiac arrest. A single animal survived in the ventilator group, but five animals suffered from cardiac arrest at an average of 11.8 min after initiation of treatment. Conventional resuscitation failed in these animals, but four animals were successfully resuscitated after the establishment of ECMO. A significant decrease was noticed in PO 2 with increasing HbCO, but there was no increase in pulmonary vascular resistance. No differences in H&E-stained lung tissue biopsies were observed., Conclusions: The use of ECMO following severe CO poisoning greatly improved survival compared with conventional resuscitation in an experimental porcine model. This study forms the basis for further research among patients.

Although carbon monoxide (CO) poisoning presents infrequently, it is a consequential and serious component of burn-related injuries, especially those injured via structure fire. A multitude of retrospective reviews and prospective trials have attempted to establish evidence demonstrating the ideal modality for oxygen administration in CO-poisoned patients; however, a consensus recommendation has not been reached. Given that half of fire-related patients succumb to CO poisoning, this is an imperative area of research.

Carbon monoxide (CO) is one of the most common causes of death due to intoxications. No biochemical marker is available to evaluate the severity of CO intoxication. We measured high-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6) and interleukin-10 (IL-10) levels in patients with different degrees of CO poisoning. We prospectively included 40 CO-poisoned patients admitted to emergency services. Blood samples were collected from the patients at admission (0 hour) and after treatment (six hours). While all patients received normobaric oxygen (NBO2) therapy, patients with severe CO poisoning received additional sessions of hyperbaric oxygen (HBO2) therapy. Blood samples were also collected from a group of healthy volunteers (n=40). Serum IL-6 and IL-10 levels were measured with the ELISA method while hs-CRP was quantified by turbidimetric analysis. At admission, IL-6 levels were significantly higher in the patient group compared to the control group (P=0.001), but IL-10 and hs-CRP levels were not significantly different between the groups. Compared to admission levels, IL-6 levels were higher at six hours (P=0.014). The patients were grouped according to treatment type (NBO2, HBO2) and history of syncope, but no significant differences were detected in patient subgroups regarding IL-6, IL-10 and hs-CRP levels. A weak positive correlation was found between COHb and lactate levels in patients (P=0.013; r=0.390).This study shows that IL-6 level increases in CO-poisoned patients, but it is not correlated with the severity of the intoxication., Competing Interests: The authors of this paper declare no conflicts of interest exist with this submission., (Copyright© Undersea and Hyperbaric Medical Society.)

Myocardial injury is a frequent consequence of moderate to severe CO (carbon monoxide) poisoning and a significant predictor of mortality in CO injury. Electrocardiography (ECG) is an easily accessible diagnostic tool for evaluating myocardial damage. Increased QT interval and QT dispersion are related to heterogeneity of regional ventricular repolarization and can develop into arrhythmias. It has been reported that QT interval and QT dispersion increase in patients with CO poisoning. Hyperbaric oxygen (HBO2) therapy has been used successfully in treating patients with CO poisoning. The aim of this study was to investigate change of corrected QT (QTc) interval and QTc dispersion after HBO2 therapy. This study included 31 patients with CO poisoning. QTc dispersion increased in patients with CO poisoning. The mean QTc dispersion was 54.94 milliseconds (ms) on admission. The mean QTc dispersion decreased to 35.74 ms after HBO2 therapy (P=0.003). There was also a correlation between carboxyhemoglobin level and QTc dispersion (P=0.029). HBO2 therapy, which decreases QTc dispersion, may improve the myocardial electrical homogeneity and reduce the risk of ventricular arrhythmia and cardiac death. Physicians should be aware of the effect of HBO2 therapy on myocardial damage when treating patients with CO poisoning. The ECGs should be examined carefully before referring or excluding HBO2 therapy., Competing Interests: The authors of this paper declare no conflicts of interest exist with this submission., (Copyright© Undersea and Hyperbaric Medical Society.)

Evidence on the acute effects of ambient carbon monoxide (CO) pollution on morbidity risk in developing countries is scarce and inconsistent. We conducted a multicity case-crossover study in 26 largest cities in China from January, 2014 to December, 2015 to examine the association between short-term exposure to CO and daily hospital admission. We fitted conditional logistic regression to obtain effect estimates of the associations. We also performed subset analyses to explore the health effects of CO at low levels. During the study period, a total of 14,569,622, 2,008,786 and 916,388 all-cause, cardiovascular and respiratory admissions were identified, respectively. A 1 mg/m 3 increase in the CO concentrations corresponded to a 3.75% (95% CI, 3.63-3.87%), 4.39% (95% CI, 4.07-4.70%), and 4.44% (95% CI, 3.97-4.92%) increase in all-cause, cardiovascular, and respiratory admissions on the same day, respectively. The associations were robust to controlling for criteria co-pollutants. In subset analyses, negative effects of short-term CO exposure on hospital admission were observed at lower concentrations (<1 mg/m 3 ), while positive effects were observed at higher concentrations (>2 mg/m 3 ). In conclusion, current CO levels in China were significantly associated with increased daily hospital admissions.

Carbon monoxide (CO) is a leading cause of morbidity and mortality. Treatment focuses on the rapid elimination of CO and management of hypoxia. Oxygen is the cornerstone of therapy, and usually applied via a reservoir face mask. Hyperbaric oxygen therapy eliminates CO faster, but requires extensive equipment and expertise. Non-invasive continuous positive airway pressure (CPAP) ventilation using a tight mask provides a higher inspired fraction of oxygen (FiO 2 ) compared to a reservoir face mask, and increases gas exchange. As this modality is widely available, it might represent a supplemental approach to current treatment of CO poisoning. We present two simultaneous cases of a married couple of 31- and 34-year-old patients, who concurrently suffered CO intoxication due to a faulty gas heater in their apartment. Both reported similar symptoms of headache and weakness, and carboxyhemoglobin (COHb)-levels at admission were 21% in both patients. One patient was treated by non-invasive CPAP-ventilation support with a FiO 2 of 100%, whereas the other was treated by conventional oxygen inhalation. In the patient treated by CPAP, COHb-levels fell quickly to 6% within one hour, and reached 3% after 90 min, whereas it took six hours to reach the same levels in the patient with conventional treatment. This vividly illustrates the potential of CPAP therapy as an alternative to conventional oxygen inhalation in the treatment of CO poisoning., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Background: Carbon monoxide (CO) poisoning may result in acute neurological sequelae, cognitive sequelae, and delay neurological sequelae. The administration of hyperbaric oxygen (HBO) to prevent the development of delayed neurological sequelae in CO poisoning have extensively investigated but conflicting results have been reported. We performed a systematic literature review and meta-analysis of randomized controlled trials (RCTs) evaluating HBO treatment and its effect on neuropsychometric dysfunction after CO poisoning., Methods: We searched Medline, Embase, Pubmed, and the Cochrane Register of Controlled Trials from inception to December 2017. Eligible studies compared HBO therapy with normobaric oxygen (NBO) in patients with CO poisoning., Results: Six studies compared HBO with NBO in CO poisoning patients. Compared with patients treated with NBO, a lower percentage of patients treated with HBO reported headache (16.2% vs 16.5%, relative risk [RR] = 0.83, 95% CI = 0.38-1.80), memory impairment (18.2% vs 23.8%, RR = 0.80, 95% CI = 0.43-1.49), difficulty concentrating (15.0% vs 18.4%, RR = 0.86, 95% CI = 0.55-1.34), and disturbed sleep (14.7% vs 16.2%, RR = 0.91, 95% CI = 0.59-1.39). Two sessions of HBO treatment exhibited no advantage over one session., Conclusions: The meta-analysis indicated that compared with CO poisoning patients treated with NBO, HBO treated patients have a lower incidence of neuropsychological sequelae, including headache, memory impairment, difficulty concentrating, disturbed sleep, and delayed neurological sequelae. Taking into consideration the cost-effectiveness of one session of HBO, one session of HBO treatment could be an economical option for patients with CO poisoning with high severity.

Carbon monoxide poisoning is the most commonly seen cause of poisoning in the emergency room (ER). The high affinity between carbon monoxide and hemoglobin and their complex biological characteristics greatly increase the risks of cardiac, nervous, muscular, and kidney diseases. In severe cases, patients may lose consciousness or die in just a few minutes. In recent years, hyperbaric oxygen therapy has been applied extensively in patients with severe conditions such as carbon monoxide poisoning and cerebral hypoxia. Hyperbaric oxygen accelerates the decomposition of carbon monoxide in hemoprotein. Therefore, treating patients with similar conditions in the ER with hyperbaric oxygen as soon as possible will improve their cognitive disorder and postpone their neuropsychological sequelae. ER nurses typically play a decisive role in saving patients with carbon monoxide poisoning. This research scrutinizes a case analysis of using hyperbaric oxygen to treat carbon monoxide poisoning and offers general rules for the use of hyperbaric oxygen. Further, the research elaborates from the perspective of ER nursing staffs the management and care of acute carbon monoxide poisoning and hyperbaric oxygen therapy nursing care. The aim of this research is to offer references for members of the ER nursing team and to enable this team to provide accurate and effective medical measures to patients during the "golden hours" of nursing care. Achieving this will help ensure that patients receive comprehensive nursing and care, thus reducing the harm suffered by patients and increasing the rate of survival.

Carbon monoxide (CO) poisoning, the most frequent type of poisoning, alters hemodynamics and creates tissue hypoxia that ultimately leads to thromboembolism. We herein describe a previously healthy 17-year-old male patient who developed acute CO poisoning while bathing in the same room as a gas heater. He was first treated with urokinase thrombolytic therapy at a local hospital, which proved ineffective. The patient was admitted to our hospital with unstable circulation and was diagnosed with massive pulmonary embolism combined with multiple organ dysfunction syndrome. His Acute Physiology and Chronic Health Evaluation II score was 22, and his Sequential Organ Failure Assessment score was 15. We faced a difficult decision regarding whether to perform surgical embolectomy or to repeat the thrombolysis. We opted to repeat the thrombolysis with successful results. Our experience may help clinicians manage similar cases in the future.

The effectiveness of hyperbaric oxygen treatment for acute cardiac diseases is unknown. Similarly, the effectiveness of hyperbaric oxygen treatment for carbon monoxide intoxication is also unknown, particularly for cases in which carboxyhemoglobin (COHb) levels return to normal. Our case study revolved around a healthy twenty-year-old male patient, who suffered from carbon monoxide intoxication. The patient presented to the Emergency Department unconscious. Blood workup revealed significant carbon monoxide intoxication and cardiac injury (COHb = 41%, troponin T = 0.38 ng/dl, ST depression). He was intubated and transferred to a specialist Centre for hyperbaric oxygenation treatment, whilst mechanically ventilated. COHb on arrival (5 hours later) was 4.3%. First echocardiography revealed estimated ejection fraction of 30%, moderate-severe left ventricular dysfunction and global hypokinesis. Patient received 3 rounds of HBOT; each round was 2.4 ATA, 100% O 2 and 120 minutes long within the following 24 hours. Afterwards, the patient was successfully extubated. Three days later, a second echocardiography showed remarkable improvement with normal left ventricular size and function. The patient discharged the following day without complaints or the need for long-term medication. Hyperbaric treatment for carbon monoxide intoxication with compromised cardiac function should be considered even when carboxyhaemoglobin levels have returned to normal. This is due to mitochondrial impairment caused by carbon monoxide intoxication that eventually can lead to significant cardiac deterioration., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Competing Interests: No conflicts of interest were reported.