BACKGROUND:

Carbon monoxide poisoning during pregnancy is exceptional, although it can cause significant damage to the fetus. Establishing a diagnosis of suspicion and applying the correct treatment improves perinatal outcomes.

CLINICAL CASE:

A 40-year-old woman, at 32 + 5 weeks of her seventh pregnancy, with a history of preeclampsia in one of her previous pregnancies. She came to the emergency department due to severe headache, vomiting and high blood pressure after a seizure in one of her daughters. On admission to the hospital, the patient continued with her symptoms, but with normal blood pressure. Cardiotocographic recording showed variable decelerations. Doppler ultrasound and laboratory studies were normal, except for a protein-creatinine index of 0.41 g/dL. At that time the pediatrician reported that the patient’s daughter was suffering from acute carbon monoxide intoxication. Based on this new information, venous blood gas and cooximetry studies were requested, which confirmed the diagnosis of carbon monoxide poisoning. She was given 100% normobaric oxygen. The evolution of the mother and her fetus was favorable, with disappearance of the mother’s symptoms and normalization of the cardiotocographic record.

CONCLUSIONS:

For the diagnosis of carbon monoxide poisoning, it is necessary to maintain a high index of suspicion, especially in pregnant women due to the potentially serious damage that can occur in the fetus. The correct differential diagnosis is decisive in order not to delay treatment and to reduce morbidity and mortality of the mother and fetus.