A prospective Randomised double blind controlled study comparing the analgesic efficacy of Intraperitoneal instillation of Ropivacaine with Dexmeditomidine and USG guided erector spinae plane block in patients undergoing elective laparoscopic cholecystectomy.

The study population will be divided into 2 groups of 30 subjects each.

1. Group IP will receive intraperitoneal instillation of 30ml 0.375% Ropivacaine plus 50 mcg

of Dexmeditomidine in 2ml NS

2. Group ESP will receive USG Guided ESP Block of 15ml 0.375% Ropivacaine plus 25mcg

of Dexmedetomidine in 1ml NS on each side(total of 30ml of 0.375% Ropivacaine plus 50 mcg of Dexmeditomidine in 2ml NS)

After obtaining informed written consent, on the previous day of surgery, a thorough pre anaesthetic evaluation (PAE) will be done and pre medicated with Tab. Ranitidine 150mg + Tab. Alprazolam 0.5mg. Pre-operatively and at the time of pre-anaesthetic evaluation, all the patients will be explained about the study protocol and how to score VAS to indicate their pain

perception by identifying 0 as no pain and 10 was worst imaginable pain. Patients will be asked to be Nil Per Oral for 6 hours.

On the day of surgery, patients will be shifted to Operating Room and multi parameter monitor will be connected (EDAN iM80). Baseline readings of SBP, DBP, MAP, HR will be noted. IV access will be taken using 18G IV cannula and crystalloid fluids (NS or RL) will be on flow. In Group ESP, the patient will be in the lying down lateral position with the support of assistants. The preliminary scan will be done to define and mark the required level(T7).The spinous processes will be identified and marked as midline, bilaterally 3cm from midline has to be marked for entry point. The parts will be painted with iodine and drapped .The scan will be started from lateral to medial after adjusting usg machine. The anatomical landmarks will be identified by usg machine and T7 transverse process and other 3 layers of muscle from posterior to anterior(trapezius, rhomboid, erector spinae) will be identified. After identifying sonoanatomy at T7 level, 10cm 23G needle will be inserted under USG guidance by In plane technique ,aiming the needle towards the T7 transverse process. After touching the transverse process, a total of 15ml Ropivacaine 0.375% +25mcg Dexmeditomidine(1ml),total 16ml will be administered on each side. The local anesthetic with Dexmeditomidine will be given in increments with careful repetitive aspiration to avoid intravascular injection.. Following ESP block, general anesthesia will be induced with Inj Xylocard 1.5mg/kg + 2mg /kg Inj Propofol I.V + Inj Vecuronium 0.1mg/kg body weight, after premedication with 1mg Midazolam + 2mcg/kg Fentanyl + Dexamethasone 8mg + Inj. Glycopyrollate 0.01mg/kg and preoxygenation for 3 mins.

Patients will be mask ventilated for 3 minutes and intubated with appropriate endotracheal tube. After confirming the tube inside trachea, patient will be connected to ventilator and maintained with 66% nitrous oxide and 33% oxygen with 1% isoflurane. Intra-operatively intra-abdominal pressure of 12 to 14 mm Hg will be maintained. Minute ventilation will be adjusted to maintain normocapnia (ETCO2 34 to 38mmHg).. Based on the existing literature, lower umbilical part will not be covered by the block. So will be requesting the surgeon to infiltrate the area with 5ml of 0.5% Ropivacaine.After extubation,

The patient pain will be monitored using visual analogue score scale(VAS) at times 0 to 30mins,The 0 point of time will be the moment the patient recovered from general anesthesia and responding to verbal commands. In the post-operative ward, if VAS score >4, patients will be prescribed Inj.Paracetamol 1gm IV every 6th hourly. If the pain has not subsided with Paracetamol, Inj.Tramadol 100mg IV will be given as per patient’s requirement. Total analgesic consumption in 24hrs will also be assessed(IV Paracetamol, INJ Tramadol).Patient will be monitored for any adverse effect like nausea, vomiting, sedation, respiratory depression, hypotension and bradycardia.

But, in Group IP ,patients will be pre-medicated with Inj.Midazolam 1mg IV, Inj.Glycopyrolate 0.2mg IV, Inj.Fentanyl 2mcg/kg IV, Inj.Dexamethasone 8mg IV. Patient will be pre-oxygenated for 3 minutes with 100% oxygen. Patients will be induced with Inj.Xylocard 1.5mg/kg + Inj.Propofol 2mg/kg + Inj.Vecuronium 0.1mg/kg IV. Patients will be mask ventilated for 3 minutes and intubated with appropriate endotracheal tube. After confirming the tube inside trachea, patient will be connected to ventilator and maintained with 66% nitrous oxide and 33% oxygen with 1% isoflurane. Intra-operatively intra-abdominal pressure of 12 to 14 mm Hg will be maintained. Minute ventilation will be adjusted to maintain normocapnia (ETCO2 34 to 38mmHg). Just after insertion of trocar, the study drug, which is 30 ml 0.375% Ropivacaine with 50mcg Dexmeditomidine in 2ml NS will be instilled through it.After extubation,the patient pain will be monitored using visual analogue score scale(VAS) at times 0 to 30mins,The 0 point of time will be the moment the patient recovered from general anesthesia and responding to verbal commands. In the post-operative ward, if VAS score >4, patients will be prescribed Inj.Paracetamol 1gm IV every 6th hourly. If the pain has not subsided with Paracetamol, Inj.Tramadol 100mg IV will be given as per patient’s requirement.

Time to first request of analgesia, total dose consumption of analgesics like Inj.Paracetamol and Inj.Tramadol in 24 hours will be recorded in both the groups. The incidence of shoulder pain, adverse effects like hypotension, bradycardia, nausea, vomiting, sedation will be recorded.