Treatment Of Acute Carbon Monoxide Poisoning Research Articles

Comparison of high-flow nasal cannula oxygen therapy and non-rebreather face mask in the treatment of mild carbon monoxide poisoning

Objective: To compare the efficacy of high-flow nasal cannula oxygen therapy (HFNC) and non-rebreather face mask (NRFM) in the treatment of mild acute carbon monoxide poisoning (ACOP) in reducing carboxyhemoglobin (COHb) , and to explore the feasibility of HFNC in the treatment of ACOP. Methods: Patients with mild ACOP with COHb >10% who were admitted to the emergency department of Northern Jiangsu People's Hospital from January 2015 to December 2020 were analyzed, and those with altered consciousness, mechanical ventilation and those requiring hyperbaric oxygen therapy were excluded. The patients were divided into HFNC group and NRFM group according to the oxygen therapy used in the emergency department. The COHb decline value and COHb half-life in the two groups were observed. Results: Seventy-one patients were enrolled, including 39 in the NRFM group and 32 in the HFNC group. The baseline COHb in the HFNC group was 24.8%±8.3%, and that in the NRFM group was 22.5%±7.1%, with no significant difference between the two groups (t=1.27, P=0.094) . At 60 min, 90 min and 120 min of treatment, COHb in both groups decreased, but the COHb in HFNC group was lower than that in NRFM group at the same time point (P<0.05) . After 1 h of treatment, the COHb decrease in the HFNC group (16.9%±4.5%) was significantly higher than that in the NRFM group (10.1%±7.8%) (t=4.32, P=0.013) . The mean half-life of COHb in the HFNC group (39.3 min) was significantly lower than that in the NRFM group (61.4 min) (t=4.69, P=0.034) . Conclusion: HFNC treatment of mild ACOP can rapidly reduce blood COHb level, it is a potential oxygen therapy method for clinical treatment of ACOP.

Very Late Stent Thrombosis in a Patient Presenting with Acute Carbon Monoxide Poisoning

Introduction: Carbon monoxide (CO), which is commonly referred to as the silent killer, can cause deleterious and unwanted cardiac effects. Some of these are arrhythmias, acute myocardial infarction (AMI), cardiogenic shock, heart failure, and pulmonary edema.Case Report: A 50-year-old man, complaining of dyspnea and chest pain, presented to the emergency room approximately half an hour after exposure to fire smoke. He had a history of anterior myocardial infarction 3 years previously and had been treated with a tacrolimus-eluting stent at that time. On admission, electrocardiography showed ST segment elevation in the leads D1, aVL, and V1–3, and ST segment depression in the reciprocal leads. The patient was transferred to the cardiac catheterization laboratory, and coronary angiography revealed stent thrombosis in the proximal part of the left anterior descending artery, causing 100% occlusion. The patient underwent successful balloon angioplasty and stenting. For the treatment of acute CO poisoning, he was administered oxygen. The patient’s condition continued to be stable, and he was discharged from the coronary intensive care unit.Conclusion: Patients who have undergone coronary stenting, particularly those in whom drug-eluting stents have been implanted, should be carefully investigated for AMI, stent thrombosis, or any other cardiac complications in the emergency room after CO poisoning

Hyperventilation with Maintenance of Isocapnia. An “Old New” Method in Carbon Monoxide Intoxication

IntroductionExposure to carbon monoxide (CO) is among the most common causes of acute and chronic poisonings worldwide. The crucial point of treatment of such acute poisonings is to eliminate CO from the body as fast as possible. There are currently two approaches to the management of the CO intoxication: hyperbaric oxygen therapy (HOT) and normobaric oxygen therapy (NOT). HOT is highly effective and capable of achieving the CO elimination half-time (T½) as low as 15 minutes. Unfortunately this method is expensive and not always readily available. The elimination of CO with the use of NOT (T½~70 min) is slower, but treatment can be started even on the site of the exposure and continued while the patient is transported to a hospital. The aim of the study was to evaluate the effectiveness of a method using therapeutic hyperventilation with maintenance of isocapnia (IH) in the elimination of CO in volunteers exposed to CO and to compare selected gasometric and respiratory parameters during IH with the values obtained during hyperventilation with pure oxygen (“non-isocapnic hyperventilation”–NIH).Material and methodsThe study involved 13 healthy, chronically-smoking volunteers. Each of them participated in two independent hyperventilation tests: IH and NIH. The levels of carboxyhemoglobin (COHb) and selected gasometric, cardiac and respiratory parameters were measured at 0, 10 and 20 minutes during both tests. Among 13 volunteers (8 women and 5 men) the initial COHb level was 5.0±1.5% (mean±SD) before the IH tests and 5.1±1.9% before the NIH tests (p>0.05). After 20 minutes of the procedures the mean COHb level was 2.9±0.9% for IH and 3.6±1.2% for NIH (p<0.01). The T½ of COHb was 29.6±12.2 min and 47.3±19.2 min respectively (p<0.01). After 10 minutes of NIH respiratory alkalosis was noted in 11 participants (84.6%). Such problem was not seen during the IH procedures. No serious adverse effects were recorded during either IH or NIH. Mild symptoms such as: dyspnea, headache and paresthesias were reported by 6 volunteers (46%) during both IH and NIH tests. It is worth noting that paresthesias were only reported during NIH, by 2 participants (15.4%).ConclusionsThe elimination T½ of CO during IH was comparable with the values reported during HOT, and lower than can be achieved with NOT or NIH. No serious adverse effects were reported during IH procedures. Further studies, especially direct comparisons with NOT and HOT, are necessary to evaluate the effectiveness of IH in the treatment of acute CO poisoning.