Observation of the effect of methylene blue on nitrite poisoning

Abstract

Objective To summarize the clinical features,diagnosis and treatment of acute nitrite poisoning by analysis of clinical cases.Methods Twenty-two cases of acute nitrite poisoning were reported.The clinical manifestations and therapeutic effect of methylene blue were analyzed.Twenty-two cases were confirmed as nitrite poisoning caused after curing.Only 1 case had a history of definite oral nitrite at emergency time.The common clinical symptoms were nausea,vomiting,chest tightness,palpitations,dizziness and fatigue.Serious cases had loss of consciousness,breathing difficulties and even coma,respiratory failure.All of the 22 cases had signs of skin and mucous membrane cyanosis.Lips and nail bed was the main and common part of cyanosis.Specific antidote methylene blue was adjusted dosage according to the cyanosis.Results All of the 22 cases were cured without complications.Sixteen cases were intravenous push methylene blue 20 mg,and the symptoms of cyanosis and chest tightness released,after observation for 24 h,and to be away from hospital.Five cases were given methylene blue 40 mg within 30 min,and released.One case who want to commit suicide,13 years old,body weight 40 kg,was given methylene blue 60 mg within 30 min and was given mechanical ventilation,gastric lavage,after 3 d and to be away from hospital.All patients had no sequel.Conclusions The clinical symptoms of nitrite poisoning patients are nonspecific.The patients with cyanosis signs is safe and effective treating with methylene blue.Appropriate application of methylene blue can obviously shorten the course of acute nitrite poisoning. Key words: Nitrite poisoning; Methylene blue; Cyanosis; Mechanical ventilation