The effect of deep and awake extubation on emergence agitation after nasal surgery: a randomized controlled trial

Emergence agitation (EA) is characterized by psychomotor agitation, excessive activity, and sensory impairment that occurs in the early stage of recovery from general anesthesia. Its clinical manifestations are similar to those of hyperactive delirium, both manifesting as excessive physical behaviour. Although EA is not exactly the same as emergence delirium, the two have been used interchangeably in some studies [1]. EA is mostly self-limiting, however, it can cause severe complications and adverse events, such as hemodynamic fluctuations, bleeding, reoperation, self-extubation, aspiration, hypoxia, injury, prolonged hospital stay, and increased hospital costs [2]. Owing to the sense of suffocation caused by nasal packing [3], postoperative EA is more common in patients after nasal surgery, ranging from 52% to 55.4% [4, 5].

The etiology of EA after general anesthesia has not yet been determined; however, existing studies suggest that many factors can increase the incidence of EA, such as preoperative cognitive impairment, obesity, younger age, recent smoking, sevoflurane anesthesia, pain, and the presence of a tracheal tube or a urinary catheter[6‐8]. The presence of an endotracheal tube is the most significant risk factor for agitation during the recovery period after nasal surgery, increasing the risk of EA by approximately five times [6]. Awake extubation after nasal surgery is preferred because the airway is contaminated with blood and/or obstructed with surgical packs [4]. However, extubation under deep anesthesia can reduce the incidence of perioperative respiratory adverse events such as cough, bronchospasm [9],and hemodynamic fluctuations [10].

Few studies have investigated the effect of extubation on the incidence of EA after nasal surgery in adults. We designed a prospective randomized controlled trial to compare the efficacy and safety of tracheal extubation under deep anesthesia versus the awake state for reducing EA in adult patients undergoing nasal surgery.

A total of 202 patients were enrolled in the trial and randomly assigned to either extubation under deep anesthesia (group D, n = 101) or extubation when awake (group A, n = 101). Fifteen patients were excluded (failure to meet extubation conditions), leaving 187 patients for the per-protocol analysis (Fig. 1). Baseline characteristics and intraoperative data of the study population are summarized in Table 1. There were no significant differences between the two groups except for the type of surgery and remifentanil dosage.

The main finding of the present study was that extubation under deep anesthesia reduced the incidence of EA after nasal surgery without increasing the incidence of adverse events during recovery.

EA affects the quality of recovery from general anesthesia and may cause adverse events [2]. Owing to the different evaluation criteria for agitation during recovery and the timing of the monitoring, the incidence of EA after general anesthesia reported in various studies exhibits considerable variation (3.7–52%) [4‐6, 13, 14]. Nasal packing is routinely performed after nasal surgery to reduce the risks of postoperative bleeding, hematoma, or adhesions. However, respiratory distress, pain, sleep disturbance, epiphora, and dysphagia increase significantly after nasal packing [15], suggesting that the incidence of EA may increase. Otorhinolaryngology is an independent risk factor for EA in children [16]. Therefore, postoperative agitation in patients undergoing nasal surgery requires further attention. In this study, the RASS was used to evaluate agitation during recovery, and EA was defined as having a RASS score ≥  + 1 [8]. The overall incidence of EA in the 187 patients who underwent nasal surgery was 53.5%. This percentage was similar to the incidence of EA after nasal surgery reported in previous related studies (52%–55.4%) [4, 5].

Identifying and modifying the risk factors can reduce the incidence of EA. The presence of invasive devices such as endotracheal tubes, urinary catheters, nasogastric tubes, and chest tubes is a risk factor for EA [1, 6‐8, 14], which can cause embarrassment, pain, and discomfort in patients. Previous studies on EA have mostly focused on retrospective factorial analyses and the effects of drug interventions on postoperative agitation. Multivariate regression analysis in a retrospective study by Kim et al.[6] suggested that an endotracheal tube can increase the risk of EA by five times. In our prospective randomized controlled trial, the incidence of EA in the awake extubation group was approximately twice that of the deep anesthesia extubation group (72.8% vs. 34.7%), demonstrating that the presence of an endotracheal tube increased the risk of postoperative EA.

In healthy adults, the nasal airways provide half of the airway resistance to airflow [17], and nasal breathing dominates during sleep [18]. After nasal packing, discomfort during mouth breathing can cause dyspnea in patients undergoing nasal surgery. Postoperative nasal packing aggravates the respiratory disturbance index, oxygen desaturation index, and snoring duration of obstructive sleep apnea (OSA) in patients with mild OSA but not in patients with moderate or severe OSA [19]. This may be because patients with chronic nasal congestion are likely dependent on mouth breathing, and postoperative nasal packing has little effect on dyspnea compared with preoperative nasal packing. In this study, we assessed the symptoms of nasal obstruction between the two groups of patients and found no significant difference in the degree of nasal obstruction before surgery, indirectly ruling out the effect of postoperative mouth breathing adaptation on the incidence of postoperative EA. Since nasal packing was performed postoperatively in all patients in both groups, the difference in the incidence of EA between the two groups was most likely due to the presence of an endotracheal tube.

There were no significant differences in the anesthesia data between the two groups, except for the remifentanil dosage. Kavalci et al. [20] observed that remifentanil reduced the incidence of EA in adults after septoplasty. In this study, remifentanil was only administered during the surgery according to the clinically recommended dose and was discontinued at the end of the procedure. However, variables with an ASD > 0.196 between the groups were all statistically corrected, excluding the influence of remifentanil on the test results. In this study, the anesthesia protocols of the two groups were the same, and BIS was used to assess the depth of anesthesia. After unblinding, the deep anesthesia group was administered a continuous low-dose propofol infusion to meet the extubation conditions. This also explains why the spontaneous breathing recovery and extubation times of patients in the deep anesthesia group were longer than those in the awake extubation group (Table 2). Compared with total intravenous anesthesia, sevoflurane anesthesia is a recognized risk factor for post-anesthesia agitation [5, 6, 8]. The occurrence of EA after nasal surgery under general anesthesia can be significantly reduced by using total intravenous anesthesia rather than volatile induction and maintenance of anesthesia [8]. All patients in this study were maintained under total intravenous anesthesia to confer superior surgical field visibility and reduce intraoperative blood loss [21]. There was no significant difference in VAS scores between the two groups after the operation, excluding the influence of postoperative pain on the incidence of agitation.

In common clinical practice, advocates of awake extubation believe that the patient's airway may be contaminated after nasal surgery, and restoration of airway reflexes will prevent the development of adverse perioperative respiratory events. Conversely, anesthesiologists promoting deep extubation argue that patients are less likely to strain and cough during extubation, which may reduce adverse events such as bronchospasm and laryngospasm [4]. Extubation under deep anesthesia can significantly reduce the incidence of post-tonsillectomy cough in children with preoperative respiratory diseases (35% vs. 60%), whereas the incidence of airway obstruction relieved by simple airway maneuvers in children extubated while deeply anesthetized is greater (26% vs. 8%) [9]. Juang et al. [22] performed extubation under deep anesthesia in 300 adult patients undergoing head, neck, and ocular surgeries, and 13% of the patients had at least one complication after extubation (including persistent cough, desaturation SpO2 < 90% for longer than 10 s, laryngospasm, stridor, and bronchospasm). However, these complications were easily reversible and did not require severe intervention, such as reintubation. In this study, there was no significant difference in the incidence of airway obstruction between the deep anesthesia extubation and awake extubation groups (10.5% vs. 4.3%, p < 0.05). All airway obstructions were relieved after simple treatments, including changes in body position, inhalation of oxygen, jaw thrust, and insertion of oropharyngeal airways. Extubation under deep anesthesia is a safe option.

Although no significant differences were observed in the incidence of postoperative hypotension or hypertension between the two groups, hemodynamic fluctuations were more pronounced in the awake extubation group. At the time of extubation, the MAP of both groups increased; the MAP of the awake extubation group was significantly higher than that of the deep anesthesia extubation group. This difference persisted until 30 min after surgery. This may be because stimulation during tracheal extubation can cause hypertension and increase plasma catecholamine secretion [23], while extubation under deep anesthesia reduces extubation stress and improves patient comfort [9, 10, 24]. Large hemodynamic fluctuations may increase postoperative bleeding, suggesting that extubation under deep anesthesia may reduce the risk of postoperative bleeding in patients undergoing nasal surgery.

Compared to patients in the awake extubation group, those extubated under deep anesthesia after nasal surgery had a lower incidence of EA and fewer hemodynamic fluctuations without an increase in adverse events.