ACID-BASE ABNORMALITIES ASSOCIATED WITH COCAINE TOXICITY IN EMERGENCYDEPARTMENT PATIENTS

There is little information on the prevalence and clinical presentatio n of acid-base abnormalities associated with cocaine toxicity. To addr ess these issues, arterial blood gas results were evaluated in 156 coc aine-associated emergency department patient visits. Arterial blood ga s results were obtained as part of the patient's clinical assessment. The majority of patients (52%) had a normal pH (7.35 to 7.45). Thirty- three percent of patients were acidotic, with a pH between 6.4 and 7.3 5. In 33 patients the acidosis was metabolic, with a HCO3- of 14 +/- 6 mmol/L. The acidosis was primarily respiratory in 18 patients, with e vidence of hypoventilation. Hypoventilation was generally secondary to chest trauma or decreased mental status. Alkalosis (pH > 7.45) was ob served in 15% of patients, and was usually respiratory, as evidenced b y tachypnea and a low PCO2. These results indicate that metabolic and respiratory acid-base abnormalities are common during cocaine toxicity . Acidosis and alkalosis were associated with numerous patient present ations, including chest pain, shortness of breath, decreased mental st atus, trauma, and seizures. Acid-base abnormalities do not appear to b e associated with a specific route of cocaine self-administration, Pat ients with a history of potential cocaine toxicity should be evaluated for acid-base abnormalities.