Comparing Fentanyl Dosages of 1 Microgram per Kilogram of Body Weight and of 1.5 Micrograms per Kilogram of Body Weight in Relation to Cough Suppression during Bronchoscopy Procedures

Abstract

BACKGROUND: Anaesthesia at bronchoscopy is a unique challenge for the anaesthesiologist as both the anaesthesiologist and operator work in the same airway. It is essential that administration of sedative agents must achieve the desired depth of sedation without risking airway patency, ventilation function and cardiovascular function. About 25% of bronchoscopy patients cite cough as the most unpleasant effect of this procedure. Fentanyl is widely chosen for a sedative agent because of their analgesic, sedative, and antitussive effects, however there has been no data regarding the optimal dose of fentanyl to suppress cough in bronchoscopy procedures.

METHODS: We designed a research with 18 subjects received fentanyl in a dose of 1 μg / kgBW, 18 subjects received fentanyl in a dose of 1.5 μg / kgBW and 18 subjects received propofol in a dose of 2 mg / kgBW as a control group. We observed the depth of sedation using the Ramsay sedation score and duration of cough suppression in their bronchoscopy procedures. We also observed the alteration of blood pressure, pulse rate, respiratory rate and oxygen saturation.

RESULTS: There was a significant difference in the depth of patient sedation between the control group and the treatment groups; as patients without fentanyl treatment were sedated deeper on the Ramsay 4 scale, patients in the treatment groups with either fentanyl of 1 µg / kgBW or 1.5 µg / kgBW had the depth of sedation on the Ramsay 2 scale and unable to reach moderate sedation as expected. Subjects with fentanyl treatments showed significantly better suppression effects against coughing compared to control group patients. As there also was a significance difference in suppression effects for coughing between the group receiving fentanyl treatment of 1 µg / kgBW and the group receiving fentanyl treatment of 1.5 µg / kgBW, we noticed a fentanyl treatment of 1 µg / kgBW was adequate to suppress cough although a dose of 1.5 µg / kgBW would show better cough suppression effect. Subjects in control group with 2 mg / kgBW of propofol experienced a more significant alteration in vital signs than the fentanyl group, either with a dose of 1 µg / kgBW or 1.5 µg / kgBW. Comparing and statistically analysing the two treatment groups of different dose of fentanyl, we found no significant difference in vital signs alteration between the two groups.

DISCUSSION: Our study revealed that as fentanyl significantly suppressed cough reflex and larger dose would provide longer period of suppression. Subjects with fentanyl treatment showed more favourable altercation in systolic and diastolic blood pressure, pulse rate, respiratory rate and oxygen saturation compared to subjects in control group with 2 mg / kgBW of propofol, but comparing and statistically analysing the two groups of different dose of fentanyl, we found no significant difference in vital signs alteration.