Comparison between I-gel® and endotracheal intubation in terms of the incidence of postoperative sore throat following thyroid surgery: a randomized observational trial

Abstract

Background: Postoperative sore throat (POST) is a common complication following thyroid surgery with an endotracheal tube (ET). The I-gel^® is a supraglottic airway device that has greater advantages in airway management compared with ET. This prospective trial aimed to explore the potential benefits of I-gel^® compared with ET on POST.

Methods: In this trial, 106 patients, classified using the American Society of Anesthesiologists (ASA) physical status classification system, belonging to classes I and II, aged 18-65 years old who were prearranged for elective radical thyroidectomy, were randomly divided into the ET and I-gel^® groups. All patients underwent total intravenous anesthesia (propofol, sufentanil, and cisatracurium). The incidence and severity of POST and postoperative hoarseness (PH) at 1, 6, 24, and 48 h following the operation were assessed and compared between the two groups. Moreover, the hemodynamic data during anesthesia were recorded and compared. Opioid consumption (sufentanil, propofol, and remifentanil) and postoperative nausea and vomiting were recorded. The visual analog scale scores for pain at the incision site 1, 6, 24, and 48 h postoperatively and Ramsay Sedation Scale scores were also evaluated and recorded.

Results: No significant difference was observed in the incidence of POST 1, 6, 24, and 48 h postoperatively (61.2% vs. 51.0%, P=0.309; 75.5% vs. 83.7%, P=0.316; 83.7% vs. 85.7%, P=0.779; and 12.2% vs. 22.4%, P=0.182, respectively) and the severity of sore throat (P=0.392) following surgery between the ET and I-gel^® groups. The incidence of PH in the I-gel^® group was significantly lower than that in the ET group 1, 6, 24, and 48 h postoperatively (all P<0.05). Compared with the ET group, a significantly less fluctuation in heart rate 1 min after intubation (P=0.045) and extubation (P=0.001) was observed in the I-gel^® group.

Conclusions: Although the I-gel^® cannot reduce the incidence and severity of POST in patients with normal BMIs following thyroid surgery, it can reduce the occurrence and severity of PH compared with ET. The I-gel^® showed superior results in terms of insertion time and better hemodynamic condition during intubation.

Keywords: I-gel®; Sore throat; endotracheal tube; hoarseness; thyroid surgery.

Figure 1

Consort flow chart that outlines patients assignment and treatment protocols. Patients were allocated into two groups (Group I-gel^®, Group ET) to receive airway management with I-gel^® or tracheal tube respectively, following a computer-generated randomization code.

Figure 2

A. Hemodynamic profiles mean artery pressure (MAP); B. Hemodynamic profiles heart rate (HR); C. VAS scores of the incision site at different time points after thyroid surgery. No significant difference was observed in MAP at baseline, intubation, 1 min after intubation, 3 min after intubation, 5 min after intubation, end of surgery, and extubation between both groups. However, the HR values were significantly lower in the I-gel^® group than in the ET group 1 min after endotracheal intubation (P=0.045) and extubation (P=0.001). Postoperative VAS scores for incision site pain between the two groups were not significantly different. MAP, mean artery pressure; HR, heart rate; ET, endotracheal tube.

Figure 3

The force diagram of laryngeal mask or endotracheal tube on pharynx in the surgical position with overextension of the neck in thyroid surgery. Patients are maintained at supine position with the neck extended. The arrow represents the direction of compression. In the hyperextension position, the posterior pharyngeal wall, epiglottis and entrance of the esophagus are under compression by I-gel^®. The epiglottis, vocal cords, and trachea wall are compressed by the tracheal tube.