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Introduction with Hypothesis: Postoperative sore throat (POST) and postoperative hoarseness (PH) are common but disturbing complications following endotracheal intubation. Previously recognized risk factors for POST are: female gender, the size of endotracheal tube, grade of difficulty in intubation, duration of surgery (1, 2) and increased cuff pressure. There is inconsistency in the literature as to the age group that is at greatest risk for developing POST (1). Risk factors associated with PH are endotracheal tube size (3) and non-optimal intubation conditions . Therefore, identification of risk factors associated with POST and PH would add to our knowledge of predictors of poor outcome in our patients.

Methods: This was a secondary analysis of prospective, cross-sectional data collected from patients previously enrolled in a randomized controlled trial (n=100 women). Eight different variables were analyzed in order to detect possible association between endotracheal intubation and the development of POST or PH. At the Post-Anaesthesia Care Unit, the patients rated their POST on a four-point scale (0=none, 1= mild, 2=moderate, 3=severe). The data was dichotomized, to sore throat (grade 1-3 on the four-grade scale) and no sore throat (grade 0 on the same scale). PH was assessed on a binary scale. The independent variables were analyzed against the dependent variables  using the Chi-Square test, and the odds ratio (OR) and confidence interval (CI) were calculated for each significant variable.  

Results: Three patients were excluded. Thus, a total of 97 women completed the study.Three variables were found to be significant risk factors for the development of POST: age >60 yrs n=14/22 (63%) vs. 18-60: n=24/75 (32%) (P  = 0.008), endotracheal tube size 7.0 i.e n=25/49 (51 %) vs. ETT 6.0: n= 13/48 (27 %) (P = 0.016) and the use of throat pack i.e n= 9/14 (64 %) vs. no throat pack: n=29/ 83 (35%) (P  = 0.037). The corresponding odds ratio (OR) for these three risk factors were: age 3.71 (95% CI 1.4-10.1), ETT 2.80 (95% CI 1.2-6.6) and throat pack  3.35 (95% CI 1.0-10.9) respectively. 20 cm i.e n= 17/29 (59 %) vs. > 20 cmH₂O: 24/67 (36%) (P= 0.038). The OR was 2.5 (95 % CI 1.0-6.1) if the cuff pressure was < 20 cm H₂O compared to if the cuff pressure was > 20 cm H₂O. 

Discussion and Conclusion: Patient-reported outcome measures research is based on the knowledge that we, as nurse anesthetists, get some insight into how the patient perceives different situations. Therefore, it is important to increase our knowledge of the patients at risk and the conditions under which this risk increases. In conclusion, we found that women over 60 years, a larger size on the endotracheal tube or the use of a throat pack are at an increased risk for developing postoperative sore throat. A lower cuff pressure was the only factor that contributed towards postoperative hoarseness.