Evaluation of cardiac and non-cardiac side effects of low dose oxytocin used during caesarean section

Aim: Low-dose administration (<5 units) of oxytocin used in the prophylaxis of postpartum haemorrhage has been recommended because of its haemodynamic side effects.We aimed to analyse the cardiac and non-cardiac side effects of oxytocin, which we prefer to administer 2 units as a low dose, in a large patient population.Material and Methods: In this observational drug study, patients aged 18-40 years with ASA II physical status scheduled for elective caesarean section under spinal anaesthesia were included.Oxytocin 2 unit intravenous bolus in 5-10 seconds was administered after placenta removal.23 unit/1000 ml oxytocin infusion was started to be administered within 4 hours after bolus.Cardiac side effects such as hypotension, tachycardia, arrhythmia, T-negativity, ST depression and other adverse effects such as nausea-vomiting, headache, flushing, burning sensation on the face, metallic taste on the tongue after oxytocin bolus were assessed.Results: The study included 417 patients.Tachycardia was the most common cardiac side effect with a rate of 42.9%, while T-negativity was the least common cardiac side effect with a rate of 1%.Hypotension was observed in 14.6%, chest pain in 10.1% and dyspnea in 5.5%.Headache was the most common noncardiac side effect (21.6%).The most common type of headache was throbbing (12.5%).Nausea-vomiting occurred in 13.7%, metallic taste on the tongue in 9.4%.56 patients required methylergonovine.The estimated blood loss was 618.5 ± 326.3 ml.Discussion: Cardiac and non-cardiac side effects can be seen even with low dose (2 unit) oxytocin administered bolus in 5-10 seconds.