The prospective study will be conducted in the department of anaesthesiology, D.Y. Patil Hospital, Navi Mumbai.  

STUDY DESIGN:   

Following Ethical Committee approval, a prospective randomised controlled study will be conducted in 120 patients who are scheduled to undergo tympanoplasty under local anaesthesia and intravenous sedation. A detailed history will be taken and relevant physical examination and investigations required will be done. Patients and relatives will be thoroughly explained regarding the nature of study. Informed consent will be taken fitting the inclusion and exclusion criteria. Each patient will be monitored in the operating room till the patient is shifted to the recovery room.  

¢ STUDY DURATION: 2018 – 2021  

¢ ELIGIBILITY CRITERIA  

Inclusion criteria: patients giving consent  

  Patients undergoing elective tympanoplasty surgery    Patients aged between 18 to 50 years  

  Patientd under ASA 1 and ASA 2 Exclusion

criteria:  

               Patient refusal  

Patient with ASA 3 or more  

                              Patient on any opioid or sedative medication or  taking                         

                                                     alcohol                                                              

Hypersensitivity reaction  

STUDY PROCEDURE  

After obtaining approval of the Ethics Committee and written informed consent from the participants, 120 American Society of Anaesthesiologists grade I and II (ASA I and ASA II), patients of either sex aged between 18 to 50 years of age, scheduled for elective tympanoplasty under local anaesthesia and intravenous sedation will be included in this prospective randomised controlled clinical study.  

Patients on other analgesics, sensitivity to drug etc will be excluded from the study.  

Detailed pre-anaesthetic check-up of all the patients posted for surgery will be done a day prior to the surgery. All the patients will be kept nil per oral for more than 8 hours prior to the surgery. Patients will be randomly divided into 2 groups of 60 each as group A or group B by picking up random numbered chits labelled as A or B. On the day of surgery, patients will be brought to the operation theatre, iv line will be secured with a 20G intracath, standard monitors attached, baseline parameters recorded. Premedication will be given with glycopyrolate 4mcg/kg, injection ondenseteron 4mg iv. With randomisation and blinding, either of the study drugs will be given along with injection dexmedetomidine 1 mcg/kg IV over 10 minutes followed by 0.4 mcg/kg/ hour. ^[13] Group A will recieve nalbuphine 0.2 mg/kg and group B will recieve injection 0.02 mg/kg. After 10 minutes, local anaesthesia will be given with 26 Guage needle. Intraoperatively, response to needle prick will be noted while giving local anaesthesia. Response as “no” or “tolerable pain” will be interpreted as adequate analgesia. Response as “behavioral changes”, “vocal response” and strong “facial grimacing” interpreted as inadequate  

analgesia. ^[16]  

Pulse rate, blood pressure, spo2 changes will be noted at 0 minutes (baseline) and after every 15 minutes post sedation and at the end of surgery.  

Intraoperatively sedation scale noted as Ramsay 1 to 6 at 10, 30 and 60 minutes post sedation.  

Ramsay 1: conscious, agitated, restless  

Ramsay 2: conscious, oriented, tranquil  

Ramsay 3: responds to verbal commands only  

Ramsay 4: asleep, brisk response to light glabellar tap  Ramsay 5: asleep, sluggish response to light glabellar tap.  

Ramsay 6: asleep, no response to glabellar tap  

Ramsay 1 to 3 being awake interpreted as poor sedation. Whereas Ramsay 4 to 6 being asleep interpreted as good sedation.  

Intraoperative discomforts like intense ear noise, headache, neck pain, backache, positional discomfort, nasal and upper lip itching, claustrophobia, earache etc as complained by the patient will also be noted.  

Dexmedetomidine 0.5 mcg/kg/hr will be used as a rescue agent intraoperatively.  

Postoperatively duration of first onset of pain noted as complained by patient.  

After onset of postoperative pain rescue analgesic will be given with injection diclofenac sodium 75 mg intramuscularly. ^[17]  

STATISTICAL METHODS  

Sample size:   

The sample size is based on earlier reported data for analgesic efficacy with Nalbuphine (Patel S et al, 017). This study reported analgesic efficacy of 90% with Nalbuphine. We assume Butarphanol to be superior with analgesic efficacy of 99%.    

Group sample sizes of 55 in study group and 55 in control achieve 80.08% power to detect a difference between the group proportions of 0.0900.   

The proportion in group one (the study group) is assumed to be 0.9000 under the null hypothesis and 0.9900 under the alternative hypothesis. The proportion in group two (the control group) is 0.9000. The test statistic used is the one-sided Likelihood Ratio test.   

The significance level of the test was targeted at 0.0500. The significance level actually achieved by this design is 0.0618.  

Thus, a total of 60 in study and 60 in control group will be used for the study (total 120 patients).  

Data expression:  

Data for counts and discrete data will be expressed as numbers with percentages, whereas measurement data for pain and vital parameters scores will be expressed as means, median with standard deviation (SD) and standard error of mean (SEM). 95% confidence intervals (C.I.) shall be presented.  

Study hypothesis:  

Null hypothesis (H0):   There are no differences between the two groups with respect to the analgesic efficacy.  

Alternate hypothesis (H1):          The analgesic efficacy of Butorphanol is better than Nalbuphine.  

Data analysis tools:  

All data will be entered into a Microsoft Office Excel (version 2013) in a spreadsheet which was prepared and validated for the data form. Data was entered and checked for errors and discrepancies. Data analysis will be done using windows based ‘MedCalc Statistical Software’ version 18.2.1 (MedCalc Software bvba, Ostend, Belgium; http://www.medcalc.org; 2014).  

Data analysis:  

The proportion of patients with good analgesic efficacy will be compared between the two groups using likelihood ratio test.  

Measurement data will be compared between the two groups using t-test and categorical data compared using chi-square test.  

All testing shall be done using two-sided tests at alpha 0.05 (95% confidence level).