After   approval of institutional  ETHICS committee, a  through pre anaesthetic assessment will be done for every patient. After obtaining written informed consent from all the patients eligible for the study,   this randomized control trial will be conducted OT complex , department of neurosurgery, Bangur institute of neurology, institute of post graduate medical education & research ( IPGMER).

    In this parallal group, randomized control trial total  70 adults  patients, aged between 20-55 years , ASA physical status I or II of either sex,preoperative GCS 14-15 scheduled for elective craniotomy for supratentorial tumour under general anaesthesia will be taken as subjects for the study. We will compare perioperative haemodynamic stability with dexmedetomidine  and  esmolol infusion in   two selective groups. The study population will be randomly allocated in two groups  with the help of  computer generated random number

 ( 1. D-GROUP –persons receiving Dexmedetomidine infusion, 2.E-GROUP-persons receiving esmolol infusion).

  Simple balanced randamization will be onduted. All the drugs will be  prepared in identical syringes by an independent anaesthesiologist who not involved in this study   . Dexmedetomidine infusion will be prepared with 2 ml dexmedetomidine ( 100µg/ml—total 200µg  ) --mixed with 38 ml normal saline (total 40 ml-  concentration 5 mcg/ ml). Esmolol infusion will be prepared with 20 ml undiluted Esmolol ( 10 mg/ml—total 200 mg)   .

   All the patients will be premedicated with 0.5 mg alprazolam at night day before surgery . Routine medications like antiepileptic, will be continued as clinically indicated .  All puncture sites will be treated with topical local anaesthetic cream . preoperative GCS was assessed for all patients.Upon arrival in the preoperating room, preoperative consciousness and sedation were assessed by HUDES score  . Five lead surface electrocardiogram( ECG)  ,pulse oximetry , NIBP  were attached. A large bore i.v. canula was inserted  and  intravenous(IV)  normal saline(NS) was started at rate of  100ml /hr. Under  local anaesthesia, A radial artery will be cannulated for arterial pressure monitoring  . Baseline HR, MAP, SPO2 all  were measured before starting study drug infusion  as basal parameters. Both the study drug infusion were started 20 mins^[34]  before induction .

Dexmeditomidine infusion  was started and  continued at the rate of 1 mcg/kg/hour wand esmolol infusion  was continued at the rate of 0.5 mg/kg/hour  for 20 min abefore induction^{[37].  .} After 20 min study drug infusion, all the patients were shifted to operative room .Thereafter, dexmeditomidine  infusion was continued at the rate of 0.2 mcg/kg/hr and esmolol is continued at 25 mcg /kg /min.The state of consciousness and haemodynamic parameters like  MAP,HR,SPO2  all were  recorded   again   (1-7) ^[38] just before induction.

   All the patients will be pre-oxyginated with 100% O2 by a face mask for 3 min and IV fentanyl( 2mcg/kg ) was administered. The patient was induced with inj propofol infusion( 0.5 mg/kg /min)^[39] and infusion will be continued until BIS SCORE reach below 50.Time to reach BIS SCORE below 50 and total propofol requirement for induction was noted. Neuromuscular block will be achieved by  requirement administering atracurium ( 0.5 mg/ kg BW)and  manual ventilation will be  continued   for at least 3 min with  100% oxygen. Laryngoscopy and intubation will be performed when TOF 0.

    MAP,HR, SPO2 will be recorded just before and after intubation and then at 1 min interval upto 5 min following intubation and thereafter ,at every 15 min intervals  till the end of operation.ETCO2  was maintained around 30-35 throughout the operation.  

   Skin will be infiltrated with 2% lignocaine+adrenaline before surgical incision. Anaesthesia was maintained with  low flow air in oxygen( 50:50—total 1 L/h). Propofol infusion was  continued throughout the operation after   at a variable  rate(25- 50 mcg/kg bw/ min) to maintain BIS <50 ^{[ 40 ]}Neuromuscular block was maintained with  IV atracurium  0.1mg/kg  as and when TOF >2  . ^[35]   

   . Hypertension (MAP> 100) and tachycardia ( HR> 100)  will be managed by injection fentanyl at 1 mcg/ kg bw for maximum consecutive two times at 15 min intervals, followed by   IV 10 mg propofol bolus, if not responded.Total intraoperative  propofol and fentanyl requirement were also noted.