Heart rate, arterial blood pressure, spo2 and sedation score (1=awake and alert, 2= sedated, responding to verbal stimulus, 3= sedated, responding to mild physical stimulus and 4=sedated, responding to moderate to severe physical stimulus) will be recorded intraoperatively every 5 mins and every 15 mins postoperatively for the first 4 hours. Hypotension and bradycardia, defined as 20% decrease in blood pressure and heart rate in relation to preblock value, will be recorded.