Lignocaine versus ketamine as an adjunct to propofol for optimal sedation during endoscopic retrograde cholangiopancreatography ERCP a randomized controlled trial

Anaesthesia Protocol:

·         Patients posted for elective ERCP will be recruited based on inclusion criteria. Patients will be explained regarding the study and informed consent will be taken.

·         Adequate fasting as per standard ASA guidelines will be confirmed.

·         Demographic data including age, sex and BMI will be recorded.

·         All ERCPs will be performed by an endoscopist who has at least 5 year experience in performing the procedure.

·         A 20 G intravenous cannula will be secured.

·         2 puffs of 10 percent lignocaine spray will be sprayed over the posterior aspect of tongue, epiglottis and posterior pharyngeal wall in sitting position.

·         Patients will be premedicated with glycopyrrolate 0.2 mg IM 15 minutes before the procedure and fentanyl 1 mcg per kg IV just prior to sedation.

·         All patients will be placed in prone position. ASA standard monitors including ECG, Pulse oximetry and non-invasive blood pressure (NIBP) monitor will be attached and baseline SpO2, heart rate and mean arterial pressure (MAP) will be recorded. Oxygen will be delivered through nasal prongs at 4 L per min.

·         In group LP:

o   Patients will receive a loading dose of lignocaine (20 mg in 1ml dilution) 1.0 mg per kg IV and a bolus dose of propofol 1.0 mg per kg IV. More up-titration with 0.5mg per kg boluses of propofol will be done till a Ramsay Sedation Score of equal to or greater than 5 is achieved. Sedation will be maintained with 2 separate infusions of lignocaine 1.0 mg per kg per hr and propofol 5 per kg per hr.

·         In group KP:

o   Patients will receive ketamine (10mg in 1ml dilution) 0.5 mg per kg per hr IV followed by propofol 1 mg per kg IV. More up-titration with 0.5mg per kg will be done till Ramsay Sedation Score of equal to or greater than 5 is achieved. Sedation will be maintained with separate infusions of ketamine 0.5 mg per kg per hr IV and propofol 5 mg per kg per hr IV.

·         Any patient movement including bucking, retching, coughing or gagging will be noted as an event of patient discomfort and propofol 0.5 mg per kg IV will be given as rescue bolus.

·         All drug doses will be calculated and administered as per true body weight or ideal body weight whichever is lower.

·         All patients will receive a maintenance infusion of Ringer Lactate at 2 mg per kg per hr.

·         During the procedure, SpO2, heart rate and MAP will be measured at the time RSS of equal to or greater than 5 is achieved and thereafter, every 5 minutes, till the end of procedure. Increase in heart rate to greater than 25 percent from baseline will be treated with propofol 0.5 mg per kg IV bolus.

o   Any fall in MAP to greater than 20 percent of baseline will be treated with ephedrine 0.1 mg per kg IV. A fall of heart rate to less than 50 per min, with parallel fall in MAP greater than  20 percent will be treated with atropine 0.01 mg per kg IV.

·         All patients will be given paracetamol 15 mg per kg IV for analgesia.

·         At the end of procedure, all infusions will be stopped.

·         The endoscopist will be asked to rate his satisfaction on a Likert Scale

 o   0 – Procedure completed without any difficulty

o   1 – Procedure possible with mild difficulty

o   2 -- Procedure possible with major difficulty

o   3 – Not possible to perform procedure.

 Â·         Upon achieving a score of 3 on RSS, patient will be shifted to the recovery room. The time of arrival in recovery room will be t0.

·         At 30 min post procedure, patients will be enquired about sore throat (pain or irritation, independent of speaking or swallowing) and asked to subjectively grade each of these symptoms on a Likert scale

o   0 – none

o   1 – mild (occasional)

o   2 – moderate (constant but bearable)

o   3 – severe (unbearable)

 Â·         The discharge criteria from PACU will be based on the Modified Aldrete Score which will be assessed every 15 minutes till a score equal to or greater than 9 is achieved.