In the realm of surgical care, the successful completion of a procedure marks only the beginning of a patient's journey towards recovery. Postoperative complications, encompassing a wide range of adverse events, can significantly impede this journey, impacting patient well-being, prolonging hospitalization, and increasing healthcare costs1. Among these complications, postoperative sore throat (POST) emerges as a prevalent and distressing concern, particularly following general anaesthesia involving endotracheal intubation2.  

POST, characterized by pain, discomfort, and a burning sensation in the throat, often accompanied by dryness, irritation, and difficulty swallowing3, can significantly diminish a patient's quality of life in the immediate postoperative period. While seemingly minor compared to other complications, POST can profoundly affect patient comfort, hindering their ability to resume oral intake, communicate effectively, and rest comfortably4.  

The reported incidence of POST varies considerably, influenced by factors such as the surgical procedure, anaesthetic technique, and patient characteristics. However, studies indicate that it affects a substantial proportion of patients undergoing general anaesthesia with endotracheal intubation, with prevalence ranging from 14% to as high as 90%5,6. This wide variability underscores the multifactorial nature of POST and the complex interplay of contributing elements.  

The process of endotracheal intubation, while essential for securing the airway during general anaesthesia, inevitably causes mechanical trauma to the delicate mucosal lining of the airway. The insertion of the endotracheal tube, its movement during surgery, and the pressure exerted by the cuff can lead to inflammation, oedema, and even ulceration of the tracheal and laryngeal mucosa7. This trauma triggers a cascade of inflammatory responses, resulting in the characteristic pain, discomfort, and associated symptoms of POST.  

While the process of endotracheal intubation itself is a major contributor to POST, several other risk factors can increase its likelihood and severity. These factors can be broadly categorized into patient-related, surgical, and anaesthesia-related factors. Patient-related factors include younger age, female gender, smoking history, pre-existing throat conditions, and body mass index8,9. Surgical factors, such as the type and duration of surgery, particularly head and neck procedures, can exacerbate mucosal trauma and inflammation6. Anaesthesia-related factors, such as the choice of anaesthetic agents, use of muscle relaxants, size and type of endotracheal tube, and duration of anaesthesia, can also influence the risk of POST. Larger tube sizes and prolonged intubation times have been specifically linked to an increased incidence of this complication10.

Recognizing these diverse contributing factors is crucial for developing effective preventive strategies and tailoring anaesthetic care to individual patients. By understanding the complex interplay of these factors, clinicians can strive to minimize the incidence and severity of POST, ultimately improving patient comfort and recovery.

The study was conducted at the Department of Anaesthesiology, Gandhi Medical College and Associated Hospital, Bhopal from May 2023 and October 2024. The sample size was calculated using the formula 4pq/d², where p is the prevalence, q is 100-p, and d is the allowable error. In this study, the prevalence of postoperative sore throat (POST) was assumed to be 65%, based on previous studies. The allowable error was set at 10%. Plugging these values into the formula, we get:  

4 * 65 * 35 / 10² = 9100/100 = 91  

That comes out to be 30 patients in each group. But we have taken a round of 105 patients, i.e., 35 in each group.

But a total of 105 patients, aged 20-60 years, with American Society of Anaesthesiologists (ASA) physical status I-II, scheduled for elective surgeries under general anaesthesia with endotracheal intubation, were included in the study to account for any potential dropouts or missing data.

Inclusion Criteria:

Patients who met all of the following criteria were included in the study:  

• Aged between 20 and 60 years.  
• American Society of Anaesthesiologists physical status I and II.  
• Undergoing surgery under general anaesthesia with endotracheal intubation.  
• Duration of surgery <2 hours.  
• Mallampati I & II.  

Exclusion Criteria:

Patients with any of the following were excluded from the study:  

• History of preoperative sore throat.  
• Recurrent nasal bleeding.  
• Pharyngeal or laryngeal disease.  
• Upper airway and oral surgeries.  
• Patient with chronic obstructive pulmonary disease (COPD) already on bronchodilator nebulization.  
• Mallampati III or more.

Table 1 – Comparison of mean age of patients according to the nebulization group

The demographic characteristics of the three study groups: Dexamethasone, Dexmedetomidine, and Ketamine. Each group consisted of 35 patients (N=35). The mean age in the Dexamethasone group was 34.6 years with a standard deviation of 10.57 years. The Dexmedetomidine group had a slightly higher mean age of 35.89 years with a standard deviation of 9.09 years. The Ketamine group had the highest mean age of 36.66 years with a standard deviation of 11.02 years.

Table 2 – Comparison of mean duration of surgery in minutes according to the nebulization group

The mean duration of surgery in minutes among the three nebulization groups: Dexamethasone, Dexmedetomidine, and Ketamine. Each group consisted of 35 patients (N=35). The Dexamethasone group had a mean surgery duration of 95.86 minutes with a standard deviation of 18.37 minutes. The Dexmedetomidine group had a slightly shorter mean duration of 93.71 minutes with a standard deviation of 18.08 minutes. The Ketamine group had the longest mean surgery duration of 98.14 minutes with a standard deviation of 14.40 minutes. The T-statistic was calculated as 0.591 with a corresponding P-value of 0.556, indicating no statistically significant difference in the mean duration of surgery between the groups.

Table 3 – Comparison of patients according to the incidence of Post-Operative Sore Throat in three nebulisation groups

The incidence and severity of postoperative sore throat (POST), graded as 0 (no sore throat), 1 (mild sore throat), and 2 (moderate to severe sore throat), across the Dexamethasone, Dexmedetomidine, and Ketamine nebulization groups at various postoperative time points (0, 2, 4, 6, 12, and 24 hours).

Table 4 – Comparison of Postoperative Hoarseness Over Time in three Nebulization Group

The incidence and severity of postoperative hoarseness, graded as 0 (no hoarseness), 1 (mild hoarseness), and 2 (moderate to severe hoarseness), in the Dexamethasone, Dexmedetomidine, and Ketamine nebulization groups at various postoperative time points (0, 2, 4, 6, and 24 hours).

At the initial 0-hour mark, a high percentage of patients in all groups reported no hoarseness (Grade 0): 91.4% in the Dexamethasone and Ketamine groups, and 85.7% in the Dexmedetomidine group. Mild hoarseness (Grade 1) was reported in 2.9%, 8.6%, and 2.9% of patients, respectively, while moderate to severe hoarseness (Grade 2) was reported in 5.7% of patients in each of the three groups.

Table 5 – Descriptive Statistics by Nebulization Group and ANOVA Results for Respiratory Rate (RR) at Different Time Points

The descriptive statistics (number of patients, mean, and standard deviation) of respiratory rate (RR) in breaths per minute for the Dexamethasone, Dexmedetomidine, and Ketamine nebulization groups at various time points: Baseline, Post Nebulization, Pre Induction, Post Induction, Post Extubation (0 hours), 2 hours, 4 hours, and 6 hours. The table also includes the F-statistic and p-value from a one-way ANOVA comparing the means of the three groups at each time point.

At baseline, the mean RR was similar across the groups: 14.97 breaths/min (SD=1.12) in the Dexamethasone group, 15.17 breaths/min (SD=1.04) in the Dexmedetomidine group, and 15.03 breaths/min (SD=1.12) in the Ketamine group. The ANOVA analysis at baseline yielded an F-statistic of 0.308 with a p-value of 0.735, indicating no significant difference in baseline RR between the groups.

In the present study, the mean age of patients was 34.6 years (SD = 10.57) in the dexamethasone group, 35.89 years (SD = 9.09) in the dexmedetomidine group, and 36.66 years (SD = 11.02) in the ketamine group. The overall gender distribution was 43.8% male and 56.2% female. These demographics are generally comparable to those reported in several other studies investigating POST prevention. For example, Vazhakalayil et al. (2023)11 included patients with a similar mean age range (33.5±12.9 & 36.83±14.5) in their two comparison groups. However, it's important to acknowledge that some studies like Kumari et al. (2019)12  (39.42 ± 10.31 & 41.30 ± 9.56 ) and Ahuja et al. (2015)13 (42.6 ± 15.1 & 40.1 ± 13.2)  included older patient populations, which could influence the generalizability of our findings to geriatric patients. The gender distribution in our study is fairly balanced, similar to many POST studies.

In the present study, the incidence of postoperative sore throat (POST) varied across time points but showed no statistically significant differences between the nebulized dexamethasone, dexmedetomidine, and ketamine groups. At 0 hours postoperatively, 65.7% of patients in the dexamethasone group, 68.6% in the dexmedetomidine group, and 60.0% in the ketamine group reported no sore throat (Grade 0). By 24 hours, these numbers increased to 88.6% in the dexamethasone group, 85.7% in both the dexmedetomidine and ketamine groups, respectively. The overall trend was a decrease in POST incidence and severity over time in all groups.

This finding of comparable POST incidence across treatment groups contrasts with several previous studies. Ahuja et al. (2015) reported a significantly lower incidence of POST in the nebulized ketamine group (20%) compared to the saline group (46%) at 4 hours postoperatively. Similarly, Mehta et al. (2022) found a lower overall POST incidence of 26.86% in the ketamine group compared to 61.19% in the saline group. These studies, which demonstrated a clear benefit of nebulized ketamine, differ from our results, where ketamine did not significantly reduce POST compared to dexamethasone or dexmedetomidine. The reasons for this discrepancy could involve differences in patient populations, surgical procedures, or ketamine dosage. Ben Sasi et al. (2022)14 observed that the incidence of POST was significantly higher in the control group compared to both the dexamethasone and ketamine groups at all-time points. In contrast, in our study, the incidence of POST was not significantly different among all groups at any time point. A significantly lower incidence of POST with both nebulized dexamethasone and ketamine compared to saline, but again, this inter-group difference was not replicated in our study.

In the present study, the incidence of postoperative cough and hoarseness was generally low, and no statistically significant differences were observed among the nebulized dexamethasone, dexmedetomidine, and ketamine groups. At 0 hours postoperatively, 88.6% of patients in the dexamethasone and ketamine groups and 85.7% in the dexmedetomidine group reported no cough. Similarly, at 0 hours, 91.4% of patients in the dexamethasone and ketamine groups and 85.7% in the dexmedetomidine group reported no hoarseness. These findings are consistent with the observation that POST often presents with a range of symptoms, but cough and hoarseness are not invariably present in all patients.

Our results contrast somewhat with those of Sharma et al. (2021)15, who specifically investigated the effect of nebulized dexamethasone on both POST and hoarseness. They found that nebulized dexamethasone significantly decreased the incidence of hoarseness compared to intravenous dexamethasone and endotracheal tube cuff soaking with dexamethasone. In our study, while hoarseness was observed, there was no significant difference between the nebulization groups. This discrepancy may be due to differences in the patient population (laparoscopic cholecystectomy in Sharma et al. (2021)15 vs. various elective surgeries in our study) or other methodological variations

The findings of this study indicate that preoperative nebulization with ketamine, dexamethasone, and dexmedetomidine generally resulted in comparable efficacy in preventing postoperative sore throat (POST) in patients undergoing general anaesthesia with endotracheal intubation. While no statistically significant differences were observed in the overall incidence or severity of POST among the three treatment groups at any of the measured time points, certain trends were noted. Specifically, there was a tendency for the dexmedetomidine group to exhibit a numerically lower incidence of POST, although this difference did not reach statistical significance.

Furthermore, while the overall incidence of postoperative cough and hoarseness was low, some patterns emerged. Dexmedetomidine and ketamine nebulization tended to be associated with a lower incidence of postoperative cough compared to dexamethasone.

1. Weiser TG, Regenbogen SE, Thompson KD, Haynes AB, Lipsitz SR, Berry WR, et al. An estimation of the global volume of surgery: a modelling strategy based on available data. Lancet. 2008 Jul 12;372(9633):139–44.
2. Singh NP, Makkar JK, Cappellani RB, Sinha A, Lakshminarasimhachar A, Singh PM. Efficacy of topical agents for prevention of postoperative sore throat after single lumen tracheal intubation: a Bayesian network meta-analysis. Can J Anaesth. 2020 Nov;67(11):1624–42.
3. Mazzotta E, Soghomonyan S, Hu LQ. Postoperative sore throat: prophylaxis and treatment. Front Pharmacol. 2023 Nov 23;14:1284071.
4. Hailu S, Shiferaw A, Regasa T, Getahun YA, Mossie A, Besha A. Incidence of Postoperative Sore Throat and Associated Factors Among Pediatric Patients Undergoing Surgery Under General Anesthesia at Hawassa University Comprehensive Specialized Hospital, a Prospective Cohort Study. Int J Gen Med. 2023;16:589–98.
5. Tsukamoto M, Taura S, Kadowaki S, Hitosugi T, Miki Y, Yokoyama T. Risk Factors for Postoperative Sore Throat After Nasotracheal Intubation. Anesth Prog. 2022 Sep 1;69(3):3–8.
6. Higgins PP, Chung F, Mezei G. Postoperative sore throat after ambulatory surgery. Br J Anaesth. 2002 Apr;88(4):582–4.
7. Adriani J, Naraghi M, Ward M. Complications of endotracheal intubation. South Med J. 1988 Jun;81(6):739–44.
8. Lee JY, Sim WS, Kim ES, Lee SM, Kim DK, Na YR, et al. Incidence and risk factors of postoperative sore throat after endotracheal intubation in Korean patients. J Int Med Res. 2017 Apr;45(2):744–52.
9. Epp K, Przybylski U, Luz C, Kriege M, Wittenmeier E, Schmidtmann I, et al. Evaluation of gender differences in postoperative sore throat and hoarseness following the use of Ambu AuraGain laryngeal mask: the randomised controlled LadyLAMA trial study protocol. BMJ Open. 2022 Jan 31;12(1):e056465.
10. Park JH, Lee YC, Lee J, Kim H, Kim HC. The influence of high-dose intraoperative remifentanil on postoperative sore throat: a prospective randomized study: A CONSORT compliant article. Medicine (Baltimore). 2018 Dec;97(50):e13510.
11. Ahuja V, Mitra S, Sarna R. Nebulized ketamine decreases incidence and severity of post-operative sore throat. Indian J Anaesth. 2015 Jan;59(1):37–42.
12. Ben Sasi OEM, Attia ZM, Hassn AMA, Aamer RMM. Effect of Nebulized Dexamethasone versus Nebulized Ketamine on Postoperative Sore Throat after Thyroid Surgeries. The Egyptian Journal of Hospital Medicine. 2022;87(1):1613–8.
13. Fisher MM, Ramakrishnan N, Doig G, Rose M, Baldo B. The investigation of bronchospasm during induction of anaesthesia. Acta Anaesthesiol Scand. 2009 Sep;53(8):1006–11.
14. Medani MME, Youssef MZS, Agwa A, Elsheikh MEE, Dahshan AH, Aly SAG. Comparative Effects of Preoperative Dexamethasone and Ketamine Nebulization on Minimizing Nasogastric Tube-Related Complications Following Laparoscopic Surgery. J Popl Ther Clin Pharmacol. 2024 Nov 8;31(11):109–13.
15. Mehta H, Brahmbhatt NP, Patel A, Bhamri S. Evaluation of efficacy of ketamine nebulization on reduction of incidence and severity of postoperative sore throat due to tracheal intubation- A prospective randomized controlled study. IJCA. 2022 Nov 28;9(4):415–21.