To Evaluate The Incidence Of Post-Operative Swallowing Impairment In Patients Undergoing Prolonged General Anesthesia With Endotracheal Intubation

Abstract

Background: Endotracheal intubation is either oral or nasal placement of a tube to the trachea for airway management. There have been multiple reports of postoperative swallowing dysfunction in patients undergoing surgery. The mechanism of swallowing impairment is multifactorial and includes mechanical causes, cognitive disturbances after surgery and residual effect of narcotics, sedatives and anesthetic drugs. Several studies have been done on swallowing impairment and dysphagia in critically ill patients in ICU, but as per our none has been done to know the swallowing impairment in patients operated electively. Swallowing dysfunction increases risk of pulmonary aspiration which can lead to serious complications. These complications can increase prolong length of ICU stay, increases number of hospital days and morbidities. This study is planned with purpose to evaluate the incidence of swallowing impairment in electively operated patients undergoing prolonged general anesthesia under endotracheal intubation.
Materials and methods: This was a prospective observational study on patients undergoing elective surgery requiring orotracheal or nasotracheal intubation for duration of more than 6 hours. All the patients were given general anesthesia with endotracheal intubation using standard institutional protocol. The surgical procedure was performed as per proposed plan. All the patients were extubated in the operation theatre and shifted to post-operative unit. Patients were assessed 6 hours after extubation with the swallowing assessment scale (SAS) which was adopted from Eckardt Symptom Score scale. The SAS was used for bolus swallowing examination in which, after recording the vitals of the patient, 3 ml of the distilled water was given for swallowing. Patient was examined for any voice change, cough response, or signs of aspiration like tachycardia or fall in saturation. If patient was able to swallow successfully, 50 ml of distilled water was given to the patient for drinking and was evaluated by SAS. Patient was further evaluated six hourly till 24 hours. If the patient fails to pass the bolus swallow examination (BSE) test at any point of time, patient was said to have severe swallowing impairment. The incidence and severity of swallowing impairment were recorded at different time point for each patient.
Results: A total of 208 patients were assessed for the eligibility of the study. 150 patients satisfied the inclusion criteria, and so, were included. Swallowing impairment after BSE with 50 ml of water was present in 14 patients, and thus, the incidence of swallowing impairment after general anesthesia with endotracheal intubation in this study was found to be 9.3%. Blood oxygen saturation was significantly lower in patients with swallowing impairment (p<0.05) at all point of observation, while other hemodynamic parameters (heart rate, respiratory rate, and blood pressure) were comparable in both group of patients (p>0.05). The study shows that swallowing impairment is not significantly associated with age, sex or type of surgical procedure performed (p>0.05).

Conclusion: The results indicate that systematic assessment of swallowing difficulties in the patients undergoing prolonged general anesthesia with endotracheal intubation is important to prevent complications associated with swallowing disfunction.