Incidence and Severity of Postoperative Pharyngolaryngeal Complications following Use of Baska Mask versus Endotracheal Intubation.

BACKGROUND: Use of Baska Mask, since a supraglottic airway device, could result in low incidence of postoperative pharyngolaryngeal complications. AIMS: The objectives were to compare the effect of Baska Mask versus endotracheal intubation on the incidence and severity of postoperative sore throat (POST), postoperative hoarseness of voice (POHV), and postoperative cough (POC). SETTINGS AND
DESIGN: This prospective randomized study was conducted in a tertiary care teaching institute in 120 patients undergoing short laparoscopic surgeries. SUBJECTS AND METHODS: Airway was secured using with low-pressure, high-volume cuffed endotracheal tube in Group T and with Baska Mask in Group B. POST, POC, and POHV were assessed at 2, 6, 12, and 24 h after surgery. Those with Grade III score throat were managed by gargling with dispersible aspirin 75 mg. STATISTICAL ANALYSIS USED: Pearson's Chi-square test, Fisher's exact test, and independent sample t-test were used as applicable.
RESULTS: Group B patients required significantly more attempts at securing airway. Incidence of POST was significantly higher in Group T as compared to that Group B at 2, 6, 12, and 24 h after surgery. POC was significantly more in Group T at 2, 6, and 12 h. No patient in Group B had POC at 12 and 24 h. POHV showed significantly higher incidence in Group T at 2 and 6 h. No patient in Group B had hoarseness at 6, 12, and 24 h.
CONCLUSION: Use of Baska Mask as compared to endotracheal intubation significantly reduces the incidence and severity of pharyngolaryngeal complications such as POST, POC, and POHV in patients undergoing short laparoscopic surgeries. Copyright:

INTRODUCTION

Endotracheal intubation with cuffed tubes protects the airway from aspiration. However, the need of laryngoscopy to introduce it as well as mucosal irritation due to the presence of the tube usually results in postoperative pharyngolaryngeal complications. Although the condition is considered self-limiting,[1] the symptoms can be quite distressing to the patients. Baska Mask is a relatively new supraglottic airway device which due to the presence of gastric sump channels offers protection against aspiration.[2] Since it does not require laryngoscopy to insert and is devoid of cuff, the use of Baska Mask could result in low incidence of postoperative dysphonia, dysphagia, and sore throat.[3]

Aim of study

The primary objective of the present study was to compare the effects of use of Baska Mask versus cuffed endotracheal tube for securing the airway on the incidence and severity of postoperative sore throat(POST) in patients undergoing short laparoscopic surgeries. Secondary objectives included the assessment of postoperative hoarseness of voice(POHV) and postoperative cough(POC) in these patients.

SUBJECTS AND METHODS

The present study was a prospective, randomized, double-blinded study which was conducted after obtaining approval from hospital ethical committee and patients’ consent. One-hundred and twenty patients aged 18–60years, of the American Society of Anesthesiologists(ASA) physical status Classes 1–2, undergoing short elective laparoscopic surgeries such as laparoscopic sterilization or diagnostic laparoscopy were included in the study. Patients with anticipated difficult airway who required more than three attempts at securing the airway or had nasogastric tube inserted intraoperatively and those with preoperative sore throat or already on analgesics or steroids were excluded from the study. Those patients in whom duration of surgery had exceeded 2 h were also excluded from the study.

One-hundred and twenty patients were recruited into the study[Table 1]. The patients were randomly allotted into two equal Groups B and T, based on computer-generated random sequence of numbers. Using sealed opaque envelops allocation concealment was ensured. All patients received general anesthesia as per a standardized protocol. They were preoxygenated with 100% oxygen for 3 min, followed by intravenous fentanyl 2 μg/kg, glycopyrrolate 0.2 mg, and midazolam 1 mg. Patients were induced with propofol till there was loss of response to verbal commands.

Table 1

CONSORT flow diagram

Atracurium 0.5 mg/kg was given, and 3 min later, a quick laryngoscopy lasting not more than 15 s was performed using Macintosh laryngoscope in Group T. Patients were intubated with a low-pressure, high-volume cuffed polyvinylchloride endotracheal tube with 6.5–7-mm internal diameter. Endotracheal tube cuffs were filled with the minimal volume of air required to prevent an audible leak. Intraoperatively, the cuff pressure was checked immediately after intubation and thereafter every 30 min using Cuff Inflator/Pressure Gauge Portex (Smiths Medical) cuff pressure monitor. Intracuff pressure was maintained at 20–22 cm of H2O throughout surgery.

In Group B, airway was secured using a size 3 Baska Mask (Logikal Health Products Pty Ltd, Morisset NSW 2264, Australia) which was introduced blindly. All insertions were performed by anesthetists with experience of successfully placing at least 15 Baska Masks earlier. Correct placement was confirmed with the appearance of end-tidal carbon dioxide tracing and by auscultation. Number of attempts taken to place Baska Mask as well as endotracheal tube was noted in both groups. External manipulation for proper placement of airway device was not considered as an additional attempt. However, repeat laryngoscopy in Group T and reintroduction of Baska Mask into the oral cavity after removal in Group B were counted as an additional attempt. Patients who required more than three attempts at laryngoscopy and/or required a bougie for intubation in Group T as well as those in whom a Ryle's tube was inserted were excluded from the study. Those who required more than three attempts for proper placement of Baska Mask were also excluded in Group B.

Anesthesia was maintained using oxygen in air (1:2) with 1.5%–2% end-tidal sevoflurane with mechanical ventilation to maintain end-tidal carbon dioxide levels at 30–35 mmHg. Atracurium 5 mg was repeated at half an hour interval to provide adequate muscle relaxation. Intravenous paracetamol 1 g was given half an hour after induction. Rise in heart rate and/or mean arterial pressure more than 20% from the baseline value was initially managed by increasing the inspired concentration of sevoflurane to 2.5%–3%. If the hemodynamic changes did not respond, fentanyl was repeated at 20 μg as boluses.

At the end of surgery ondansetron, 4 mg was given, and the residual neuromuscular blockade was reversed with neostigmine 0.05–0.07 mg/kg and glycopyrrolate 10 μg/kg. Patients were extubated following gentle oropharyngeal suctioning under vision. Postoperatively, all patients received paracetamol 1 g 8 hourly and tramadol 100 mg on demand intravenously. If this failed to control surgical pain, intravenous fentanyl 20 μg incremental boluses were given. Total intraoperative as well as postoperative opioid consumption were documented.

POST, cough, and hoarseness of voice were assessed at 2, 6, 12, and 24 h based on the scales described in Table 2.[4] Those with Grade III score throat were managed by gargling with dispersible aspirin 75 mg which was repeated as many times as needed till there was relief from the symptoms. The number of times rescue therapy was required, and the modality of management were also noted.

Table 2

Assessment of postoperative sore throat, cough, and hoarseness of voice

Postoperative sore throat	Grade
Severity
No sore throat at any time since the operation	0
Minimal – Patient answered in the affirmative when asked about sore throat	1
Moderate – Patient complained of sore throat on his/her own	2
Severe – Patient is in obvious distress	3
Postoperative cough
No cough at any time since the operation	0
Minimal	1
Moderate	2
Severe	3
Postoperative hoarseness of voice
No complaint of hoarseness at any time since the operation	0
Minimal – Minimal change in quality of speech. Patient answers in the affirmative only when enquired about	1
Moderate – Moderate change in the quality of speech of which the patient complains on his/her own	2
Severe – Gross change in the quality of voice perceived by the observer	3

Pearson's Chi-square test or Fisher's exact test was used to compare the categorical variables such as gender, ASA physical status, number of attempts at securing airway, Mallampati score, incidence and severity of POST, and hoarseness of voice and cough. Independent sample t-test was used to compare the continuous variables such as age, weight, intraoperative opioid consumption, and duration of intubation among the groups. Statistical analyses were performed using the SPSS version 20.0 for Windows (IBM Corporation ARMONK, NY, USA).

RESULTS

Mean age, weight, duration of intubation, and intraoperative consumption of fentanyl were comparable in both Groups T and B. Distribution of gender, Mallampati score, and ASA physical status classes also did not show any significant difference between groups. However, Group B patients required significantly more attempts at securing airway as compared to Group T (P = 0.012) [Table 3].

Table 3

Comparison of demographics, American Society of Anesthesiologists physical status classes, Mallampati score, and intraoperative fentanyl consumption

Continuous variables	Mean±SD		P
	Group T	Group B
Age (years)	47.90±12.17	49.70±8.81	0.709
Weight (kg)	65.8±9.2	60.9±9.6	0.093
Fentanyl consumption (µg)	159.2±8.9	157.4±10.5	0.436
Duration of intubation	92.9±10.46	94.58±6.5	0.607
Categorical variables	Group T, n (%)	Group B, n (%)	P
Gender
Male	30 (50)	18 (30)	0.333
Female	30 (50)	42 (70)
Mallampati score
1	42 (70)	48 (80)	0.716
2	18 (30)	12 (20)
ASA physical status
I	28 (46.7)	24 (40.0)	0.602
II	32 (53.3)	36 (60.0)
Attempts at securing airway
1	58 (96.7)	42 (70.0)	0.012
2 or 3	2 (3.3)	18 (30.0)

ASA=American Society of Anesthesiologists, SD=Standard deviation

Incidence of POST was significantly higher in Group T as compared to Group B at 2, 6, 12, and 24 h after surgery. POC was significantly more in Group T at 2, 6, and 12 h. No patient in Group B had POC at 12 and 24 h, and the incidence of POC was comparable in both groups at 24 h. Hoarseness of voice showed significantly higher incidence in Group T at 2 and 6 h. No patient in Group B had hoarseness at 6, 12, and 24 h postoperatively. In Group T, there was no incidence of hoarseness at 24 h [Table 4]. Figures 1–3 show that the incidence and severity of POST, POC, and POHV were higher in Group T as compared to Group B at all time points postoperatively.

Table 4

Comparison of incidence of postoperative sore throat, cough, and hoarseness of voice

Time	Occurrence	Group T, n (%)	Group B, n (%)	P
Postoperative sore throat
2 h	No	6 (10.0)	52 (86.7)	<0.001
	Yes	54 (90.0)	8 (13.3)
6 h	No	8 (13.3)	56 (93.3)	<0.001
	Yes	52 (86.7)	4 (6.7)
12 h	No	32 (53.3)	54 (90.0)	0.003
	Yes	28 (46.7)	6 (10)
24 h	No	48 (80.0)	60 (100.0)	<0.024
	Yes	12 (20.0)	0
Postoperative cough
2 h	No	6 (10.0)	56 (93.3)	<0.001
	Yes	54 (90.0)	4 (6.7)
6 h	No	18 (30.0)	58 (96.7)	<0.001
	Yes	42 (70.0)	2 (3.3)
12 h	No	48 (80.0)	60 (100.0)	<0.024
	Yes	12 (20.0)	0
24 h	No	56 (93.3)	60 (100)	0.492
	Yes	4 (6.7)	0
Postoperative hoarseness of voice
2 h	No	42 (70)	58 (96.7)	0.012
	Yes	18 (30)	2 (3.3)
6 h	No	54 (90.0)	60 (100.0)	<0.237
	Yes	6 (10)	0
12 h	No	56 (93.3)	60 (100)	0.492
	Yes	4 (6.7)	0
24 h	No	60 (100)	60 (100)	NA
	Yes	0	0

NA=Not available

Figure 1

Incidence and severity of postoperative sore throat

Figure 3

Incidence and severity of postoperative hoarseness of voice

Incidence and severity of postoperative cough

DISCUSSION

Till recent past, it was considered a norm that all laparoscopic surgeries should be performed under general anesthesia with controlled ventilation through a cuffed endotracheal tube to reduce the risk of aspiration. However, with the introduction of newer supraglottic airway devices with a separate channel for drainage of gastric contents, it is generally agreed that these devices could be safely used as an alternative device to cuffed endotracheal tubes during general anesthesia with controlled ventilation.

Postoperative laryngopharyngeal complications result from an aseptic inflammatory process caused by irritation of the pharyngeal mucosa during laryngoscopy and tracheal mucosa due to endotracheal tube cuff. Trauma during laryngoscopy and intubation is another major contributing factor. As supraglottic airway devices do not require laryngoscopy for proper placement, use of these devices produces less POST as compared to endotracheal intubation. It was found that Baska Mask and I Gel result in comparable laryngopharyngeal comorbidities in surgical patients undergoing laparoscopic cholecystectomy.[35]

Hoarseness of voice and cough are symptoms very often associated with POST. The most common reasons implicated in the development of POC are use of larger sized endotracheal tubes and laryngeal trauma. Use of small-sized tubes and periodic measurement of cuff pressure are generally found to reduce mucosal damage and thereby hoarseness as well.[6] As supraglottic airway devices do not come in contact with tracheal mucosa, and since laryngeal trauma is also less, their use is associated with a lesser incidence of POC and hoarseness.

Kuvaki et al.[7] had observed that the 1st h POST, dysphonia, and dysphagia were significantly higher following endotracheal intubation as compared to the use of LM-Supreme™. However, conflicting results were obtained with the use of ProSeal laryngeal mask versus endotracheal tubes. In the study by Saraswat et al.,[8] no significant difference in laryngopharyngeal morbidity was noted between intubation and ProSeal laryngeal mask groups, whereas Parikh et al.[9] found postoperative soreness of throat to be more following endotracheal intubation. A meta-analysis has shown that there was significantly higher blood staining on the mask noted with laryngeal mask airway (LMA) ProSeal compared to I-Gel.[10] The higher incidence of mucosal trauma with LMA ProSeal could be contributed to the higher pharyngeal complications observed with its use.

Baska Mask®, a relatively new supraglottic airway device, was found to offer a superior airway seal pressure with minimum complications in comparison to an I-Gel® device.[11] Various studies have proven the safety and efficacy of Baska Mask in laparoscopic surgeries.[35] With the use of Baska Mask, the incidence of postoperative throat pain, dysphonia, and dysphagia was found to be low.[12] Although Baska Mask may not be as easy as classic LMA (cLMA) for inserting, it provides a better seal with glottic aperture and is considered as a useful alternative to the cLMA.[13]

It has been suggested that learning curve of Baska Mask insertion is short and prior placement of 15 Baska Masks may be sufficient to learn the correct technique. However, in our study, although all Baska Mask insertions were performed by anesthetists with more than 15 successful placements, we found that 30% of patients in our study required 2 or 3 attempts for correct placement. However, it was noted that incidence and severity of POST were significantly less in Baska group as compared to those who were intubated. This observation clearly reinstates the advantage of Baska Mask in reducing postoperative laryngopharyngeal complications.

Incidence of POST can be as high as 45.4% following endotracheal intubation, and the common predictors are airway management, female sex, younger patients, gynecological surgeries, succinylcholine,[14] and even type of laryngoscope used.[15] Although topical drugs such as magnesium or ketamine nebulization[161718] as well as inhaled steroids[19] provide good protection, the use of Baska Mask helps to achieve the same results avoiding any drug administration.

The drawbacks of our study were that all the intubations and Baska Mask insertions were not performed by a single anesthetist. Although all were done by anesthetists with comparable experience, varying individual skills might have influenced the outcome.

CONCLUSION

The use of Baska Mask as compared to endotracheal intubation significantly reduces the incidence and severity of pharyngolaryngeal complications such as POST, POC, and POHV in patients undergoing short laparoscopic surgeries.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.