ABSTRACT

In recent years it has been noted that opioids, which are generally known to have antitussive effects, might cause coughs. This especially occurs during anaesthesia induction and in some instances (increased intracranial, intraocular and intraabdominal pressures) can harm the patient. Many solutions have been proposed for this condition of unidentified origin. We investigated the effect of dexmedetomidine on the cough produced by fentanyl.

The study was performed on 40 patients of ASA physical status I-II, which were scheduled for any elective surgery. Patients with Chronic Obstructive Pulmonary Disease, with a history of cigarette smoking, Upper Respiratory Tract Infection in the last two weeks and patients using ACE inhibitors were not included. Patients were randomly divided into two groups: the control group (Group P; n=20), and the dexmedetomidine group (Group D; n=20). These groups were treated with iv normal saline and dexmedetomidine, respectively. After 10 minutes, both groups were treated with fentanyl (2.5 µg kg-1 in 2 seconds). The number of coughs after the injection of fentanyl was recorded for a period of 1 minute.

Six (30%) out of 20 patients in the control group experienced cough, while 2 (10%) of the patients in the dexmedetomidine group coughed. We have found that the clinically observed incidence of cough in the dexmedetomidine pre-treated group was decreased, but this was statistically insignificant (p=0.235).

Pre-treatment with iv 1 µg kg-1 dexmedetomidine may suppress the fentanyl-induced cough during general anaesthesia induction, but more clinical trials are needed to evaluate its effect.

Keywords: Fentanyl, cough, dexmedetomidine