Pharyngeal Mucosal Conditioning to Prevent Postoperative Sore Throat in Septoplasty Patients With Severe Nasal Obstruction

BACKGROUND:

Existing literature on POST in nasal surgery treats all septoplasty patients as homogeneous, regardless of nasal obstruction severity. Patients with severe obstruction (NOSE score ≥55) are chronic mouth-breathers who bypass normal nasal air humidification, producing measurable pharyngeal mucosal dehydration, epithelial thinning, and chronic dry inflammation - a pre-existing vulnerability amplified by intubation and throat pack placement.

INTERVENTION:

Group A (Intervention): Nebulized 0.9% NaCl (5 mL, 15 min via compressor jet nebulizer, particle size 2-5 µm) administered 30 minutes pre-induction with patient breathing through mouth; plus water-soluble lubricant gel (K-Y Jelly or equivalent) applied to ETT cuff and distal 5 cm.

Group B (Control): Sham nebulization (room air, identical device and duration); ETT lubricated with plain water only.

STANDARDIZED PROTOCOL (both groups):

Induction: propofol 1.5-2 mg/kg + fentanyl 1-2 µg/kg + rocuronium 0.6 mg/kg. Maintenance: sevoflurane 1.0-1.5 MAC in O2/Air (no nitrous oxide). ETT cuff maintained at 20-25 cmH2O (checked every 30 minutes by calibrated aneroid manometer). Standardized saline-soaked throat pack for all patients. Awake extubation with single gentle suction.

NOVEL ELEMENTS:

1. First RCT to enroll nasal surgery patients specifically by NOSE score severity
2. First study to test preoperative mucosal conditioning as a POST prevention strategy in chronic mouth-breathers
3. Preoperative mucosal hydration measured by Modified Schirmer Test and VAS dryness score before and after nebulization

RANDOMIZATION AND BLINDING:

Computer-generated block randomization (variable blocks of 4 and 6), stratified by NOSE severity (55-75 vs 80-100). Allocation concealed via sequentially numbered opaque sealed envelopes. Outcome assessor and patient blinded; anesthesiologist not blinded but is not the outcome assessor.

SAMPLE SIZE:

n=105 (52-53/group); 80% power; two-sided alpha=0.05; anticipated 65% POST incidence in control group; clinically meaningful absolute reduction of 35%; 15% dropout allowance.

• Nebulized 0.9% Normal Saline (Device): 0.9% Normal saline 5 mL nebulized over 15 minutes via compressor jet nebulizer (target particle size 2-5 µm) administered 30 minutes before anesthetic induction, with patient breathing normally through the mouth to maximize pharyngeal deposition.
• Water-Soluble Lubricant Gel on Endotracheal Tube (Device): Water-soluble lubricant gel (K-Y Jelly or bioequivalent) applied uniformly to the ETT cuff outer surface and distal 5 cm of the ETT shaft immediately before endotracheal intubation.
• Sham Nebulization (Device): Identical compressor nebulizer device delivering room air only, operated for 15 minutes. Device produces the same sound and airflow as the active nebulizer. No saline delivered.

Primary outcomes

• Incidence of Postoperative Sore Throat (POST) at 1 Hour Post-Extubation [1 hour after extubation]: POST assessed by a blinded PACU nurse using a validated 4-point categorical scale: 0 = no sore throat; 1 = mild (only on direct questioning, no analgesic required); 2 = moderate (spontaneous complaint, non-opioid analgesic given); 3 = severe (spontaneous complaint, opioid analgesic required). POST is considered present if score ≥1.

Secondary outcomes

• POST Severity - Visual Analogue Scale [1 hour, 6 hours, and 24 hours post-extubation]: POST severity scored on VAS 0-10 (0=no pain, 10=worst imaginable pain) by blinded assessor at 1h, 6h, and 24h.
• Incidence and Severity of Hoarseness [Hoarseness graded 0-3 (0=none; 1=mild/perceived only; 2=moderate/noticed by others; 3=severe/aphonia).]: 1 hour, 6 hours, and 24 hours post-extubation
• Incidence and Severity of Dysphagia [1 hour and 6 hours post-extubation]: Dysphagia graded 0-3 (0=none; 1=mild; 2=moderate/significant difficulty; 3=severe/unable to swallow).
• Incidence of Postoperative Nausea and Vomiting [6 hours and 24 hours post-extubation]
• Time to First Analgesic Request for Throat Pain [From extubation to 24 hours post-extubation]: Time in minutes from extubation to first patient-initiated request for analgesia specifically for throat pain.
• Preoperative Pharyngeal Mucosal Hydration [Before and after nebulization/sham, approximately 30-40 minutes pre-induction]: Mucosal hydration measured by patient VAS dryness score (0-10). Measured before and after nebulization to confirm intervention effect.
• Patient Satisfaction with Recovery [24 hours post-extubation]: Numerical Rating Scale 0-10 (0=completely unsatisfied, 10=completely satisfied).
• Dose-Response Correlation - NOSE Score and POST Severity [24 hours (pooled data)]: Exploratory Pearson/Spearman correlation between preoperative NOSE score (continuous variable) and POST VAS across both groups

Sex: All, ages: 18 Years to 60 Years

Inclusion Criteria:

* Age 18 to 60 years
* ASA physical status I or II
* NOSE score ≥55 (severe or extreme nasal obstruction category) at preoperative assessment
* Duration of nasal obstruction symptoms ≥6 months
* Scheduled for elective septoplasty ± turbinoplasty under general anesthesia with endotracheal intubation
* Mallampati class I or II
* BMI ≤35 kg/m²
* Written informed consent obtained

Exclusion Criteria:

* Current or past smoker (any amount)
* Gastroesophageal reflux disease (GERD) or laryngopharyngeal reflux (LPR)
* Known pharyngeal or laryngeal pathology
* Active upper respiratory tract infection within 2 weeks of scheduled surgery
* Preoperative sore throat or baseline pharyngeal pain at time of assessment
* Anticipated difficult airway (Mallampati class III-IV, mouth opening less than 3 cm)
* ACE inhibitor use (causes dry cough, confounds POST assessment)
* Concurrent tonsillectomy, adenoidectomy, or rhinoplasty extending operative time beyond 90 minutes
* Known allergy to lubricant gel components
* Severe systemic disease affecting mucosal hydration (Sjögren's syndrome, uncontrolled diabetes mellitus, end-stage renal disease)
* Pregnancy or breastfeeding
* Previous participation in this study

• Mohamed Ahmed Tolba, MD, Principal investigator, Mansoura University - Qassim University Medical City