Haemodynamic Responses to Laryngoscopy and Endotracheal Intubation After Intravenous Dexmedetomidine: A Comparison Between Two Doses

Abstract

BACKGROUND Many pharmacological drugs are used to attenuate the haemodynamic response to laryngoscopy and endotracheal intubation. Dexmedetomidine, a highly selective α2 agonist has pharmacological properties like sedation, sympatholysis, analgesic property and less respiratory depression with preservation of the ventilator response to carbon dioxide and makes it an ideal adjuvant drug during general anaesthesia, in comparison to other drugs. In this study we compared the effects of two different doses of Dexmedetomidine on the haemodynamic responses during laryngoscopy and endotracheal intubation. MATERIALS AND METHODS Ninety patients of American society of anesthesiologists (ASA) physical grades I and II undergoing general anaesthesia were randomly allocated into three groups of 30 patients each. Values of heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial blood pressure (MAP) were recorded before giving the drug. Group A, Group B and Group C received 20 ml of Inj. Normal Saline, Inj. Dexmedetomidine 0.5 µg/Kg diluted to 20 ml with normal saline and dexmedetomidine 0.75 µg/Kg body weight diluted to 20 ml normal saline respectively as infusion over 10 minutes. Sedation scores were also recorded 1 min and 3 min after giving the test drugs. HR, SBP, DBP, MAP were recorded 1 min, 3 min, 5min, and 10 minutes after laryngoscopy and intubation. RESULTS The increase in HR, SBP, DBP and MAP after intubation were significantly less in Group C than Group A and Group and B and lasted longer than Group A and Group B. Sedation score was significantly low in Group C than Group A and Group B CONCLUSION Both the doses of Intravenous dexmedetomidine 0.5 µg/Kg body weight and 0.75 µg/Kg body weight attenuate the haemodynamic response of laryngoscopy and endotracheal intubation, but the dose of 0.75 µg/Kg body was found to be more effective than 0.5 µg/Kg body weight.