Prevalence of Abnormal Methemoglobinemia and Its Determinants in Patients Receiving Nitroglycerin During Anesthesia

Abstract

Background One of the complications of nitroglycerin infusion during surgery is methemoglobinemia. Objectives The aim of this study was to investigate the prevalence of methemoglobinemia and its association with nitroglycerin infusion for the treatment of hypertension during general anesthesia. Methods Patients received nitroglycerin infusion at a dose of 2 μ/kg/min. The aim of controlling blood pressure was to set the blood pressure at 20% of the patient’s baseline. Then, the amount of methemoglobin was recorded at 15-minute intervals. Backward stepwise logistic regression test was used to determine the factors affecting methemoglobinemia. Results Based on the criterion of methemoglobin level above 2%, the prevalence of pathologic methemoglobinemia was 56.6%. After adjusting for confounding variables in the final model, the total prescribed dose was the only factor affecting pathologic methemoglobinemia. Conclusions For the first time, we showed that more than half of the patients undergoing surgery suffered from methemoglobin level above 2% after prescribing nitroglycerin, and the only predictor of abnormal methemoglobin level was the rate of nitroglycerin prescription. Anesthesiologists are recommended to be more careful about the speed of nitroglycerin infusion, and if the patient needs higher doses, patient care for the early detection of methemoglobinemia should be the priority.

Derin Beyin Stimulatörü Uygulanan Hastalarda Skalp Bloğu ve İnfiltrasyon Anestezisinde Methemoglobinemi Riski

“…In healthy individuals, the NADH cytochrome b5 reductase enzyme maintains the MetHb level at <2%. However, some studies have shown that the nitroglycerin MetHb level >2% used during general anesthesia in antihypertensive treatment is as the only cause (10). In our study, the MetHb level was >2% in two patients (20%) who underwent scalp block and in six patients (19.3%) who underwent infiltration anesthesia.…”

“…Dapsone, sulfonamides, benzocaine, primaquine, and some local anesthetics have been reported as causes of acquired MetHb. (9,10). In clinical practice, it occurs mostly as a result of the use of local anesthetics (6).…”

Prevalência e fatores relacionados a metahemoglobinemia em indivíduos da atenção básica de Anápolis-Go

“…A prevalência obtida na amostra estudada tem grande possibilidade de corresponder à prevalência da população brasileira pela proximidade dos parâmetros populacionais encontrados nesse estudo -proporção de indivíduos do sexo feminino (61%), faixa etária (50% dos indivíduos entre 31 a 55 anos) e cor da pele (35% brancos) -, com os parâmetros divulgados pela Pesquisa Nacional de Saúde (PNS) -proporção de sexo feminino em 57%, faixa etária (43% dos indivíduos entre 30 a 49 anos) e cor da pele, 40% brancos (MENEZES et al, 2015). Nos estudos internacionais analisados (SADEG et al, 2008;IMANI et al, 2019) Por fim, não foi observada relação da doença com o tabagismo, mesmo sabendo que o tabagismo apresenta relação direta com a concentração de monóxido de carbono (SILVA, 2005).…”

Mapping blood biochemistry by Raman spectroscopy at the cellular level

“…Since in the present studies we extract libraries of Raman tensors (both resonant and non-resonant) it is possible to model local anisotropies according to the procedures as we discussed recently. 30 This would be helpful to detail cellular mechanisms of blood oxidative stress, 10,11 methemoglobinemia 49,50 and other anaemic tendencies. 7,8,51 Due to the unique specificity of Raman to the state of heme, the approach described herein offers a sensitive diagnostic to tackle blood biochemistry at the cellular level via monitoring of redistributions of the main forms of hemoglobin, which may not be achieved easily using any other microscopy technique.…”