A comparison between Fentanyl and Nalbuphine for intubating conditions during awake fiberoptic broncoscopy in oral carcinoma surgeries: A randomized comparative prospective study

INTRODUCTION

Oral cancer is the sixth most prevalent cancer worldwide. ¹ It is the most prevalent cancer among males in India  and is associated with tobacco and gutka use. Even if the human papillomavirus has lately been linked to the development of oral cancer, other more widespread causes in India must not be neglected. Surgery is the first-line therapy for oral cancer.² Due to the reduced mouth opening and decreased interincisor space, airway difficulty is a primary anaesthetic issue during surgery. Patients with oral cancer who undergo radiation as their primary treatment are more likely to experience limited neck motion, as well as restricted mouth opening.

Fiberoptic and video technologies are widely used during laryngoscopy for airway management. Awake fiberoptic intubation (AFOI) is the technique of choice in anticipated difficult airway situations. However, patients need to be prepared both psychologically and pharmacologically for cooperation and avoidance of violent withdrawal, vomiting or vigorous coughing, gagging, and glottic closure reflex during intubation.¹ Hemodynamic responses like increase in heart rate and blood pressure and desaturation can occur during AFOI, presenting challenges to the procedure.² Therefore, it is essential to prepare patient’s airway for obtundation of airway reflexes, providing adequate sedation and anxiolysis without the loss of airway patency with preservation of adequate ventilation.

Benzodiazepines, propofol, opioids, dexmedetomidine, etc., are some of the drugs used for this purpose. Propofol has rapid onset and offset of action with profound amnesia but is associated with apnea, hypotension, and pain on injection.³Fentanyl attenuates the hemodynamic response and discomfort during passage of the bronchoscope through vocal cords. It has a rapid onset with a duration between 30 and 50 min but may be associated with respiratory depression, nausea, vomiting, and itching during recovery.⁴

Nalbuphine is an agonist-antagonist opioid. Because of its pharmacological properties, nalbuphine results in analgesia without respiratory depression, pruritus, and sedation  due to activation of supraspinal and spinal κ-receptor. It has been administered as an analgesic supplement for conscious sedation] or balanced anesthesia and as an analgesic for postoperative and chronic pain.

Mondal S, et al (2015)  conducted a randomized double-blind prospective study  on  60 patients scheduled for elective laparotomies who were randomly allocated into two groups: Group A received dexmedetomidine 1 mcg/kg and Group B received fentanyl 2 mcg/kg over 10 min.Adequacy of intubation condition was evaluated by cough score and post-intubation score. Cough Score (1-4), post-intubation Score (1-3) and RSS (1-6) were significantly favorable (P < 0.0001) along with minimum hemodynamic responses to intubation (P < 0.05) and less oxygen desaturation (P < 0.0001) in Group A than Group B. Dexmedetomidine is more effective than fentanyl in producing better intubation conditions, sedation along with hemodynamic stability and less desaturation during AFOI.

Eldemrdash, A  et al (2017) conducted a study to evaluate and compare the efficacy of Dexmedetomidine or Fentanyl for sedation during AFOI. They conclude that Dexmedetomidine provides better intubating condition, sedation, less respiratory depression and hemodynamic stability than fentanyl for AFOI, without adversely affecting airway.

Sharma et al (2017)  conducted study to compare patients’ Observer’s Assessment of Alertness/Sedation scale (OAA/S) as primary outcome and other variables such as endoscopy, intubation condition, tolerance and haemodynamic stability among low and standard doses of dexmedetomidine. Group H had more favourable OAA/S score than that of Group L, but endoscopy and intubation time, patient tolerance, vocal cord and limb movement and satisfaction score did not differ significantly between the groups. There were no significant haemodynamic differences between the two groups. 

Aim and Objectives:

Aim:

·        To compare ease of fiberoptic intubation with intravenous nalbuphine versus fentanyl in difficult intubation patients undergoing oral carcinoma surgery

Primary Objective

·        To compare intubating conditions among two groups with intubation score (Coughing  and  post intubation score)

Secondary Objective:

·        To compare haemodynamic parameters  among  two groups.

·        To compare sedation (Ramsay sedation score)  among two groups.

Materials and Methods:

Study Setting:

The study will be conducted in Department of Anaesthesiology, King George’s Medical University, Lucknow in various operation theatres after getting clearance from the ethical committee, Research Cell, KGMU, Lucknow. 

Study Design: 

Prospective Randomized  study

Study Duration:

  18 months

                               Sample size calculation

Proposed Objective: To compare intubating conditions among two groups with intubation score, cough score and Ramsay sedation score.

We are going to perform a study to compare Fentanyl and Nalbuphine for Intubating Conditions during awake fiberoptic bronchoscopy In oral carcinoma Surgeries. In a previous study (Akheela and Chandra. Comparative evaluation of Nalbuphine and Fentanyl for attenuation of pressor response to laryngoscopy and tracheal Intubation in laparoscopic cholecystectomy. Cureus. 2021 May 20;13(5):e15142. doi: 10.7759/cureus.15142.)5 drowsy state was in 32.22% cases in Nalbuphine group and 13.33% in Fentanyl group. In present study we also expect a similar outcome. The sample size was calculated using the following formula suggested by Charan and Biswas (2013)6

 n= 2*(Zα/2+Zβ) 2 *P*(1-P)/(p1-p2) 2

 where, n: Sample size

Zα/2 : critical value of z at 95% confidence = 1.96

Zβ: critical value of z at 80% power = 0.84

 p1-p2= Difference in proportion of two events in two groups=0.19

P= pooled Prevalence = (p1+p2/2)= 0.225

n = 2* (1.96+0.84)  * (0.225)*(0.775) / (0.036) 2 = 75.75

Thus the calculated sample size is 75. Keeping a provision of data loss @ 2%, the proposed sample size is 77 patients in each group or a total of 154 case

Inclusion Criteria:

·        Patients included in the study should meet the following inclusion criteria-

·        Age- 18-70 years of either gender

·        ASA  physical status -I  or II

·        Type of surgery- Oral carcinoma surgery

·        Nature of surgery-Elective

·        MP grade III &IV

·        Type of anaesthesia- General Anaesthesia

·        Patients giving written informed consent  

•      Exclusion Criteria

·        Patient Refusal

·        MP grade I &II

·        ASA III &IV

·        Allergy to drug

·        Major cardiorespiratory disease

·        Emergency surgeries

·        Difficult mask ventilation

·        Nasal mass

·        Coagulation disorder

·        Hepatic or renal disease

·        Pregnant patients

                 METHODOLOGY:

 After taking approval from the Institutional Ethics Committee and Informed Consent, all patients will be randomly allocated to one of the two groups of 75  patients in each group , according to a computer-generated random number table. All  patients will be  kept nil per orally for 8–10 h prior to the procedure. Patients will be premedicated with Tab Alprazolam 0.25 mg night before  surgery. In pre operative room, patency of both the nostrils will be tested and the nostril with better patency will be identified and xylometazoline nasal drops will be instilled in both nostrils. An intravenous(iv)line will be secured. Injection emset 4mg and inj. Rantac 50 mg will be administered 15 minutes before surgery. Nebulization will be done with 4% lignocaine 4 ml (160 mg) over 15 min.Patient will be shifted to operation theatre (ot) table and all essential monitoring will be attached . Heart rate(HR), systolic blood pressure(SBP), diastolic blood pressure(DBP), mean arterial pressure(MAP), oxygen saturation(SPO₂) and end tidal co2(ETC02) will be recorded at baseline, just before intubation, 2 min,3 min after intubation thereafter every 5 minutes . Just before intubation O2 flow will be started at 35 lit/min via High-Frequency Nasal Cannula  (THRIVE technique)  and will be  continued until the end of intubation. Two puffs of 10% lignocaine (10 mg/puff) will be used to anesthetize tongue and hypopharynx followed by spray as you go [SAYGO] technique.

Group F :patients will receive fentanyl 2 μg/kg of body weight I.V. and Group N : patients will receive nalbuphine 0.2 mg/kg of body weight I.V. Drug will be diluted in 10 ml normal saline and administered over a period of 10 min in both the groups. Fiberoptic bronchoscope will be prepared by lubrication with lignocaine jelly and an appropriate sized cuffed polyvinyl chloride endotracheal tube will be loaded over it. At the end of study drug infusion, sedation will be evaluated by Ramsay sedation score (RSS) :- 1-Anxious, agitated, or restless  2-Cooperative, oriented, or tranquil  3-Sedated but responding to loud noise  4-Asleep, brisk glabellar reflex, or response to loud noise  5-Asleep, sluggish glabellar reflex, or response to loud noise, and 6-Asleep with no response to painful stimulus.

 Once the RSS score ≥3 was achieved, bronchoscopy will be performed through nasal approach from the more patent nostril. Oxygen will be supplemented throughout the procedure through the other nasal cavity via a HFNC. Once the vocal cords will be visualized, aliquots of 2 ml (40 mg) 2% lignocaine spray will be administered to facilitate further advancement of bronchoscope till the carina is  visualized.Tracheal tube will be rail-roaded over the fiberscope. The fiberscope will be then withdrawn and the placement of the tube will be confirmed with auscultation and ETC02 graph. General anesthesia will be induced in accordance with the standard protocol and surgery will be allowed to proceed.If propofol is required , the patient will be dropped from study group. Intubating conditions  will be evaluated in terms of cough score (1-no cough, 2-slight cough 3-moderate cough 4-severe cough during bronchoscopy) and post intubation score (1-2-minimal resistance, 3-severe resistance)The total dose of lignocaine used  during bronchoscopy will be  recorded.

REFERENCES

1. Mondal S, Ghosh S, Bhattacharya S, Choudhury B, Mallick S, Prasad A. Comparison between dexmedetomidine and fentanyl on intubation conditions during awake fiberoptic bronchoscopy: A randomized double-blind prospective study. J Anaesthesiol Clin Pharmacol. 2015 Apr-Jun;31(2):212-6. doi: 10.4103/0970-9185.155151. PMID: 25948903; PMCID: PMC4411836.

2. Ramkumar V. Preparation of the patient and the airway for awake intubation. Indian J Anaesth. 

3. Vuyk J, Sitsen E, Reekers M. Intravenous anaesthetics. In: Miller RD, editor. Miller’s Anaesthesia. 8th ed.

4. Adachi YU, Satomoto M, Higuchi H, Watanabe K. Fentanyl attenuates the hemodynamic response to endotracheal intubation more than the response to laryngoscopy.

5.mohamed kassim akheela,alka Chandra  Comparae Evaluation of Nalbuphine and Fentanyl for Attenuation of Pressor Response to Laryngoscopy and Tracheal Intubation in Laparoscopic Cholecystectomy.

    6. Charan, J. and Biswas. T. (2013)  to Calculate Sample Size for Different                                                              Study Designs in Medical Research.