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 ¤  Abstract
 ¤ Introduction
 ¤  Materials and Me...
 ¤  Observation and ...
 ¤ Discussion
 ¤ Conclusion
 ¤ Acknowledgment
 ¤  References
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 Table of Contents     
ORIGINAL ARTICLE
Year : 2015  |  Volume : 11  |  Issue : 4  |  Page : 251-256
 

I-gel as an alternative to endotracheal tube in adult laparoscopic surgeries: A comparative study


1 Department of Anaesthesiology, Pandit Deendayal Upadhyay Medical College (PDUMC), Rajkot, Gujarat, India
2 Department of Surgery, Pandit Deendayal Upadhyay Medical College (PDUMC), Rajkot, Gujarat, India

Date of Submission03-Mar-2014
Date of Acceptance13-May-2014
Date of Web Publication1-Oct-2015

Correspondence Address:
Jigisha Prahladrai Badheka
"Rajiv", Raw House No. 3, Srijinagar Main Road, Near Amprapali Cinema, Rajkot, Gujarat
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/0972-9941.140210

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 ¤ Abstract 

Background: The tracheal tube is always considered to be the gold standard for laparoscopic surgeries. As conventional laryngoscopy guided endotracheal intubation evokes significant hypertension and tachycardia, we have used I-gel, second generation extraglottic airway device, in an attempt to overcome these drawbacks. We conducted this study to compare haemodynamic changes during insertion, efficacy of ventilation, and complications with the use of I-gel when compared with endotracheal tube (ETT) in laparoscopic surgeries. Materials and Methods: A total of 60 American Society of Anaesthesiologists physical status I and II adult patients undergoing elective laparoscopic surgeries were randomly allocated to one of the two groups of 30 patients each: Group-A (I-gel) in which patients airway was secured with appropriate sized I-gel, and Group-B (ETT) in which patients airway was secured with laryngoscopy - guided endotracheal intubation. Ease, attempts and time for insertion of airway device, haemodynamic and ventilatory parameters at different time intervals, and attempts for gastric tube insertion, and perioperative complications were recorded. Results: There was significant rise in pulse rate and mean blood pressure during insertion with use of ETT when compared to I-gel. Furthermore, time required for I-gel insertion was significantly less when compared with ETT. However ease and attempts for airway device insertion, attempts for gastric tube insertion and efficacy of ventilation were comparable between two groups. Conclusion: We concluded that I-gel requires less time for insertion with minimal haemodynamic changes when compared to ETT. I-gel also provides adequate positive-pressure ventilation, comparable with ETT. Hence I-gel can be a safe and suitable alternative to ETT for laparoscopic surgeries.


Keywords: I-gel, Endotracheal intubation, hemodynamic parameters, laparoscopic surgery, positive-pressure ventilation


How to cite this article:
Badheka JP, Jadliwala RM, Chhaya VA, Parmar VS, Vasani A, Rajyaguru AM. I-gel as an alternative to endotracheal tube in adult laparoscopic surgeries: A comparative study. J Min Access Surg 2015;11:251-6

How to cite this URL:
Badheka JP, Jadliwala RM, Chhaya VA, Parmar VS, Vasani A, Rajyaguru AM. I-gel as an alternative to endotracheal tube in adult laparoscopic surgeries: A comparative study. J Min Access Surg [serial online] 2015 [cited 2019 Nov 17];11:251-6. Available from: http://www.journalofmas.com/text.asp?2015/11/4/251/140210



 ¤ Introduction Top


Laparoscopic surgery is an evolving subspecialty and is not only limited to minor gynaecologic surgery or cholecystectomy, but has extended to procedures such as appendicectomy, hernia repairs, advanced gastrointestinal, urologic and gynaecologic procedures. The problems common to all such procedures are:

  1. Carbon dioxide insufflation in the body-intraperitoneal or extraperitoneal,
  2. Raised intra-abdominal pressure and
  3. Potential danger of regurgitation and pulmonary aspiration.


The anaesthesiologist must ensure a patent airway and adequate ventilation. Until date, the cuffed tracheal tube was considered as ideal for providing a safe glottic seal, especially for laparoscopic procedures under general anaesthesia. However, over a period of time, new airway devices have been added to the anaesthesiologist's armamentarium. [1] Extraglottic airway devices (EGD s ) like ProSeal laryngeal mask airway (PLMA) and the I-gel forms a more effective seal than the laryngeal mask airway (LMA) and has a drainage tube that facilitates passage of a gastric tube. It provides protection against regurgitation, and prevents gastric insufflation when correctly placed.

I-gel [Figure 1] is a truly anatomical device, without an inflatable cuff, achieving a mirrored impression of pharyngeal, laryngeal and perilaryngeal structures. It accurately positions itself over laryngeal framework providing reliable seal. Studies performed on manikins and patients have shown that the insertion of I-gel was significantly easier when compared with insertion of other supraglottic airway devices. [2],[3]
Figure 1: I-gel

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This study was conducted to compare the use of I-gel and endotracheal tube (ETT) in patients undergoing laparoscopic procedures under general anaesthesia using controlled ventilation. We compared hemodynamic changes during insertion, efficacy of ventilation, and complications with use of I-gel and ETT in laparoscopic surgeries.


 ¤ Materials and Methods Top


This prospective, comparative, randomised study was conducted after being reviewed and approved by institutional ethical committee. After obtained written informed consent of patients and relatives, 60 adult patients of American Society of Anaesthesiologists physical status I or II undergoing elective laparoscopic surgeries were randomly allocated to one of the two groups of 30 patients each. Randomisation was done using closed envelop technique. In Group-A (I-gel) appropriate sized I-gel was inserted, and in Group-B (ETT) patients airway was secured with laryngoscopy - guided endotracheal intubation. The patients having presence of any significant acute or chronic lung disease, pathology of the neck or upper respiratory tract, potential difficult intubations, mouth opening <2.5 cm, cervical spine disease, increased risk of aspiration (hiatus hernia, gastro-oesophageal reflux disease, full stomach), pregnant women, patients with body mass index (BMI) >35 kg/m 2 and all emergency surgeries were excluded from the study.

After securing intravenous (IV) line, all standard monitors like electrocardiogram (ECG), non-invasive blood pressure and pulse oximeter were applied, and patient's baseline parameters like pulse rate (PR), mean blood pressure (MBP) and peripheral oxygen saturation (SpO 2 ) were recorded. Patients were premedicated with injection glycopyrrolate 4 μg/kg, ondansetron 50 μg/kg, ranitidine 1 mg/kg and fentanyl 1 μg/kg IV. After 15 min of premedication Group-A patients were induced with propofol 2-2.5 mg/kg IV without muscle relaxant. Group-B patients were induced with propofol 2-2.5 mg/kg IV and succinylcholine 1.5-2 mg/kg IV to facilitate the endotracheal intubation. Airway devices (ETT and I-gel) of appropriate size were inserted by the experienced anaesthesiologists. Position of the airway devices and efficacy of positive-pressure ventilation were assessed by observing adequate chest rise on manual ventilation, bilateral equal air entry on auscultation, normal rectangular shape capnograph tracing, absence of leak and normal SpO 2 (>95%). After fixing the airway device, appropriate sized gastric tube was inserted. Ease of insertion of I-gel/ETT was assessed as Easy: No resistance to insertion in the pharynx in a single manoeuvre; Difficult: Resistance to insertion or more than one manoeuvre was required for the correct placement of the device and impossible: Unable to insert the I-gel/ETT. We also recorded the number of attempts and time required for insertion of airway device. The time for insertion was recorded as time from insertion of the airway device to the first capnograph trace. The ease of placement (easy: inserted in 1 st attempt, difficult: Requires >1 attempt), number of attempts required and failure of gastric tube placement was also noted.

Anaesthesia was maintained with O 2 , N 2 O, traces of inhalation agents and intermittent doses of injection vecuronium bromide. Controlled ventilation was provided with tidal volume of 8-10 ml/kg and respiratory rate set to obtain an end tidal carbon dioxide (EtCO 2 ) between 35 and 45 mmHg. At the end of surgery, neuromuscular blockade was reversed with glycopyrrolate 8 μg/kg and neostigmine 0.05 mg/kg. Removal of I-gel/extubation of ETT was done after recovery of adequate spontaneous respiration and muscle tone.

Monitoring of PR, MBP, SpO 2 , EtCO 2 , and ECG was done throughout the peri-operative period. Haemodynamic and ventilatory parameters were recorded before induction (baseline), just after intubation, then at 1, 3 and 5 min after I-gel insertion/intubation, after pneumoperitoneum, after change of position, before and 5 min after release of pneumoperitoneum and after I-gel removal/extubation.

Common complications such as coughing, laryngospasm, gastric inflation, regurgitation, aspiration, blood on device, injuries (to lip, teeth, and gum), sore throat, dysphagia and dysphonia during perioperative period were recorded.

Statistical analysis was performed using Student's t-test for comparison of data between two groups at different times of study period. The results were expressed as mean ± standard deviation for all comparisons, P < 0.05 was considered as significant. Statistical analysis was done using Graph Pad Prism version 5 for windows. Keeping the power of study at 80% and confidence interval (CI) at 95%, to detect difference in MBP, the minimum sample size required was 28 patients in each group. So we had taken 30 patients in each group. Degree of freedom (df) is 58.


 ¤ Observation and Results Top


Participants of this study were recruited from routine laparoscopic list there were no dropouts. Demographic profiles as shown in [Table 1] were comparable in both groups. No significant difference in terms of age, weight, height, BMI and duration of surgery were noted.
Table 1: Demographic profile

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In I-gel group 12/16 (75%) male patient's size 4 I-gel was inserted and 11/14 (78.5%) female patient's size 3 was inserted, as is recommended. The data regarding the size of I-gel/ETT, attempts and ease for insertion of airway device and attempts for insertion of gastric tube are shown in [Table 2]. The mean times from insertion of the airway device to the first capnograph trace was significantly less in I-gel insertion (11.28 ± 2.91seconds) when compared with ETT (14.33 ± 1.56 s) as shown in [Figure 2].
Figure 2: Time of insertion

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Table 2: Comparison of parameters between two groups

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There was no significant difference in the PR (P = 0.18, df-58, CI-95%) and MBP (P = 0.292, df-58, CI-95%) before insertion of airway device between the two groups [Figure 3]. Following insertion of airway device there was significant rise in PR (just after intubation [P = 0.0013, df-58, CI-95%], 3 min after intubation [P = 0.011, df-58, CI-95%]) and MBP (just after intubation [P = 0.0002, df-58, CI-95%], 3 min after intubation [P = 0.0001, df-58, CI-95%], 5 min after intubation [P = 0.014, df-58, CI-95%]) in Group-B patients when compared to Group-A patients. However after 5 min of intubation till the removal of airway device the changes in PR and MBP were comparable in both groups. SpO 2 and EtCO 2 between the two groups were comparable at all times [Figure 4]. SpO 2 remained >95% and EtCO 2 remained between 35 and 45 mmHg, throughout the procedure in all patients.
Figure 3: Mean pulse rate and mean blood pressure changes

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Figure 4: EtCO2 Changes

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There were no significant differences in complications associated with the use of either airway devices. On removal, visible blood indicative of mucosal injury was noticed in 2/30 (6.6%) patients of I-gel group. Injury to lips/gums/teeth and post-operative mild sore throat was observed in 3/30 (10%) patients respectively in ETT group. No incidence of coughing, bronchospasm, laryngospasm, regurgitation, aspiration or gastric insufflation has been noted in both the groups.


 ¤ Discussion Top


Laparoscopic surgery has been shown to adversely affect intraoperative pulmonary mechanics, thus providing the most severe test of the efficacy of an airway device. [4] Tracheal intubation is considered ideal for airway management in laparoscopic surgeries, as it provides adequate ventilation and protects against pulmonary aspiration even in the presence of raised airway pressure due to carboperitoneum. However, the device is not foolproof against aspiration. Endobronchial intubation is also not uncommon during laparoscopic procedures, and in difficult airway situations this may fail. I-gel and other EGD's may overcome some of these problems, even in obese patients and in those who require high airway pressure for adequate ventilation. [5]

This study was designed to compare the insertion qualities, hemodynamic changes, ventilator parameters and complications of I-gel and endotracheal intubation in laparoscopic surgeries in adult patients. The use of muscle relaxants may improve the ease of insertion. As various methods for I-gel insertion were used by different anaesthetists without use of muscle relaxants.

I-gel was easier to insert in all our patients without the use of muscle relaxant.

In our study, we chose the size of the I-gel airway according to the weight criteria of the manufacturer's recommendations: size 3 for 30-60 kg and size 4 for 50-90 kg, but some degree of overlap exists. If the patient weighed between 50 and 60 kg, the size of the I-gel was chosen at the discretion of the consultant anaesthetist depending on the patient's mouth opening, thyromental distance and neck width. [6] We inserted 15 size-3 and 15 size-4 I-gels. Indeed, Gatward et al. [7] have previously demonstrated the suitability of the size-4 I-gel in 100 non-paralysed patients weighing 42-113 kg, with findings comparable to ours. Median leak pressure 25.27 cm of H 2 O, effective in preventing aspirations. I-gel and ETT were easier to insert in all patients. I gel was placed in 1 st attempt in 25/30 (83.4%) cases and rest 5/30 (16.6%) cases required 2 nd attempt. Similar success rates for I-gel insertion were observed by previous studies. [8],[9],[10],[11] the average time for insertion of I-gel (11.28 s) was significantly less in comparison to time for ETT insertion (14.33 s). Similar observation was reported by Sharma et al. [5] and Uppal et al. [12] who found, mean time for I-gel insertion 13.67 and 12.2 s, respectively. The firmness of the tube section of I-gel and its natural oropharyngeal structures allows the device to be easily and rapidly inserted by grasping the proximal part, which helps to glide the leading edge against the hard palate into pharynx. [11] This structure of I-gel increases the success rate with first attempt even with inexperienced anaesthesiologists. Endotracheal intubation requires laryngoscopy, which may also increase the average time for insertion and hence may cause increased sympatho-adrenal activity. Results for gastric tube insertion were comparable in both I-gel (1 st attempt 86.7%, 2 nd attempt 13.3%) and ETT (1 st attempt 90%, 2 nd attempt 10%).

Laryngoscopic guided intubation evokes rise in hemodynamic response. [13],[14]

We observed the significant rise in PR and MBP just after, 3 min and 5 min after endotracheal intubation when compared to I-gel. However, the hemodynamic parameters thereafter were comparable in both groups. An abstract reports hemodynamic response to insertion/removal of the PLMA as significantly less than for tracheal intubation/extubation. [15] Hemodynamic response to laryngoscopy and intubation are a reflection of an increase in sympatho-adrenal activity due to oropharyngeal and laryngotracheal stimulation. [16] Major sources of the stimuli responsible for the adrenergic response may be the supraglottic structures distorted by laryngoscopy. [17] Hence it suggests that EGD's offer greater hemodynamic stability to insertion, during maintenance and at extubation compared to ETT.

I-gel has a soft gel like anatomical cuff made of thermoplastic elastomer that does not require inflation after its placement in the airway tract. This may prevent the stimulation of sympatho-adrenal axis and thus increase in PR and MBP. Furthermore, on comparison of haemodynamic response to insertion of I-gel and classic LMA with endotracheal intubation in one of the studies, it was found that I-gel was superior to other two airways in maintaining stable haemodynamics and was not associated with increase in IOP under general anaesthesia. [18] Other workers also drew same conclusion. [19],[20]

I-gel formed an effective seal around the glottis allowing adequate oxygenation and controlled ventilation as good as ETT. Oxygenation and ventilation were optimal in all our patients throughout the surgery as well as in post-operative period. Our results agree with those of previous study done by Maltby et al.,[4] Lu et al. [21] who compared proseal LMA with ETT and CLMA respectively. EtCO 2 were comparable in both groups. During carboperitoneum minute ventilation was increased mainly by increasing the respiratory rate rather than tidal volume. This was done to eliminate raised carbon dioxide load and prevent systemic acidosis. In a study of patients undergoing laparoscopic gastroplasty, ventilator adjustments were performed by increasing the respiratory rate by 25% and minute ventilation by 21% to counteract the increase in carbon dioxide load and prevent intraoperative acidosis. [22]

In our study, we did not observe any incidence of regurgitation. Our results were comparable with other studies. [5],[10],[11] The incidence of visible blood on I-gel after removal in our study was 6.6% (2/30 patients). The incidence of visible blood with the use of other EGD's has been quoted from 12 to 18%, depending upon type of EGD's, the technique of insertion and ease of insertion. [23],[24] Patients undergoing laparoscopy might be considered to be at risk of developing the acid aspiration syndrome. [1],[25],[26] However, the increased intra-abdominal pressure results in increase in the tone of the lower oesophageal sphincter, which allows maintenance of the pressure gradient across the gastro-oesophageal junction, and which might therefore reduce the risk of regurgitation. [1] In our study, we did not observe any incidence of regurgitation. We observed 10% (3/30) patients with ETT insertion developed sore throat and other 10% (3/30) patients developed injury to lips, teeth and gums. Singh et al. [11] have reported that the incidence of tongue, lip, and dental trauma was observed in 16.7% (5/30) patients in the PLMA group and in 3.3% (1/30) patients in the I-gel group. An another study done by Shin et al. [27] also found similar results they found I-gel may have a similar airway sealing to that of PLMA, higher than that of CLMA, and is not associated with adverse events. I-gel was designed to create a perilaryngeal anatomical seal without an inflatable cuff, decreasing the risk of compression trauma in cadaveric studies. [2] The use of the I-gel has now been shown clinically to result in fewer post-operative sore throat and neck complaints compared with disposable LMAs. [28] No other complications were reported in both groups.


 ¤ Conclusion Top


We concluded that I-gel requires less time for insertion with minimal hemodynamic changes when compared to ETT. I-gel also provides adequate positive-pressure ventilation, comparable with ETT. In addition, the gastric channel in I-gel provides protection against aspiration. Hence, I-gel can be a safe and suitable alternative to ETT for laparoscopic surgeries.


 ¤ Acknowledgment Top


We are thankful to surgery department for allowing us to do study.

 
 ¤ References Top

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Maltby JR, Beriault MT, Watson NC, Liepert D, Fick GH. The LM. A-ProSeal is an effective alternative to tracheal intubation for laparoscopic cholecystectomy. Can J Anaesth 2002;49:857-62.  Back to cited text no. 4
    
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Sharma B, Sehgal R, Sahai C, Sood J. PLMA vs. I-gel: A comparative evaluation of respiratory mechanics in laparoscopic cholecystectomy. J Anaesthesiol Clin Pharmacol 2010;26:451-7.  Back to cited text no. 5
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28.
Keijzer C, Buitelaar DR, Efthymiou KM, Srámek M, ten Cate J, Ronday M, et al. A comparison of postoperative throat and neck complaints after the use of the I-gel and the La Premiere disposable laryngeal mask: A double-blinded, randomized, controlled trial. Anesth Analg 2009;109:1092-5.  Back to cited text no. 28
    


    Figures

  [Figure 1], [Figure 2], [Figure 3], [Figure 4]
 
 
    Tables

  [Table 1], [Table 2]



 

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