The Relation between the Clinical Presentation of Acute Carbon Monoxide Toxicity and Carboxy-hemoglobin Level

Background and Objective: The symptoms of carbon monoxide (CO) poisoning are nonspecific; symptoms can mimic those of other common diseases such as nonspecific viral illness, flu- like syndrome and hypertensive attack. Elevated blood carboxy-hemoglobin (COHb) measurements are used to confirm a clinical diagnosis of exposure to CO. The main objective of this study is to study the correlation between carboxy-hemoglobin (COHb) levels and clinical manifestations in patients with acute (CO) poisoning.

Subjects and Methods: Over 6th month’s period, eighty patients who presented to Poison Control Center, Ain Shams university Hospital due to CO intoxication were included. Examination of vital signs, skin, cardiovascular (CVS), central nervous (CNS), gastrointestinal (GIT), and musculoskeletal systems were performed as well as arterial blood gases (ABG), carboxyhemoglobin level (COHb), random blood sugar, serum of sodium (Na), potassium (K+), alanine aminotransferase (ALT), serum creatine phosphokinase (CPK), serum urea and creatinine, hematological parameters (red blood cells, white blood cells and hemoglobin), serial cardiac markers (serum of aspartate aminotransferase (AST), creatine kinase-MB, lactate dehydrogenase (LDH), and cardiac troponin-I (cTnI) quantitative determination).

Results: Tachycardia was present in 46.3% of patients, cyanosis in 10%, tachypnea in 73.8%, headache in 67.5%, vomiting in 75%. There was a statistical significant negative (inverse) correlation between the mean COHb level and pH. & mean COHb level and K+. There is no correlation between COHb level and clinical presentation. There is no correlation between COHb level and the outcome in patients with CO intoxication.

Conclusions: COHb cannot be used as a prognostic marker of CO intoxication and, therefore, patients must be monitored closely.