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Comparison of the Supreme and the ProSeal laryngeal mask airway in patients undergoing laparoscopic cholecystectomy: A randomized controlled trial
Acta Anaesthesiologica Taiwanica xxx (2016) 1e7
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Research Paper
Comparison of the Supreme and the ProSeal laryngeal mask airway in patients undergoing laparoscopic cholecystectomy: A randomized controlled trial Lakesh K. Anand 1 *, Nitika Goel 2, Manpreet Singh 1, Dheeraj Kapoor 1 1 2
Department of Anaesthesia and Intensive Care, Government Medical College and Hospital, Sector 32, Chandigarh, India Department of Anaesthesiology, All India Institute of Medical Sciences, Ansari Nagar, New Delhi, India
a r t i c l e i n f o
a b s t r a c t
Article history: Received 26 May 2015 Received in revised form 18 December 2015 Accepted 7 March 2016
Objective: The single-use LMA Supreme (Teleflex, Inc., Wayne, PA, USA) and the LMA ProSeal (Teleflex, Inc., Wayne, PA, USA) laryngeal mask airway (LMA) have similar characteristics. To date, studies have not achieved a consensus regarding the oropharyngeal leak pressure (OLP) of the LMA Supreme and LMA ProSeal, and there is little information on their efficacy in laparoscopic cholecystectomy. This study compared the safety and efficacy of the LMA Supreme and LMA ProSeal devices in patients undergoing laparoscopic cholecystectomy. Method: Eighty-four eligible consenting patients were randomly allocated to the LMA Supreme group or the LMA ProSeal group. Both groups received the standard anesthesia technique. The Supreme or ProSeal LMA was inserted, the cuff was inflated to 60 cmH2O, and the LMA position was confirmed. Anesthesia was maintained using propofol and 50% oxygen in air. A gastric tube was inserted through the drain tube of the LMA to deflate the stomach, and the first attempt success rate and insertion time were recorded. During surgery, the intra-abdominal pressure was maintained at 12 mmHg. The fiberoptic view of the larynx was determined by passing a flexible fiberoptic bronchoscope. The OLPs, success rate, insertion time, hemodynamic and respiratory parameters, and complications were recorded at different time points. Results: The mean OLP was significantly lower in the LMA Supreme group than in the LMA ProSeal group (24.9 ± 5.3 cmH2O vs. 28.4 ± 5.8 cmH2O; p < 0.01). The first attempt success rate and ease of insertion grading for LMA were higher in the Supreme group. The insertion time was lower in the Supreme group than in the ProSeal group (p < 0.01). The fiberoptic view was better with the ProSeal LMA. The hemodynamic and ventilatory parameters and postoperative sore throat were comparable in both groups. Conclusion: The LMA ProSeal has a higher OLP than the LMA Supreme. The success rate of first attempt insertion and ease of insertion were better for the LMA Supreme group and the insertion time was lower in the LMA Supreme group. The Supreme and ProSeal LMAs were both effective for positive pressure ventilation in laparoscopic cholecystectomy. Copyright © 2016, Taiwan Society of Anesthesiologists. Published by Elsevier Taiwan LLC. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
Key words: laparoscopic cholecystectomy; laryngeal mask airway; oropharyngeal leak pressure; ProSeal; Supreme
1. Introduction The contemporary laryngeal mask airway (LMA) has a built-in drain tube for gastric access, and was designed to improve ventilation, airway protection, and oropharyngeal leak pressures
* Corresponding author. Department of Anaesthesia and Intensive Care, Government Medical College and Hospital, Number 3110, Sector 48-B, Chandigarh 160047, India. E-mail address: [email protected] (L.K. Anand).
(OLPs).1 Since 2002, the LMA ProSeal (Teleflex, Inc., Wayne, PA, USA) has been compared to the endotracheal tube (ETT) and the LMA Classic device (Teleflex, Inc., Wayne, PA, USA) in patients undergoing laparoscopic surgery, and is considered an alternative airway device for a wide variety of laparoscopic procedures.2e6 The LMA Supreme (Teleflex, Inc., Wayne, PA, USA) and LMA ProSeal have similar characteristics. The curved rigid airway tube of LMA Supreme makes it easy to insert, its relatively larger polyvinyl chloride (PVC) cuff provides effective OLP, and a built-in drain tube allows reasonable deflation of the stomach; hence, it may be a practical option for laparoscopic procedures.7
http://dx.doi.org/10.1016/j.aat.2016.03.001 1875-4597/Copyright © 2016, Taiwan Society of Anesthesiologists. Published by Elsevier Taiwan LLC. This is an open access article under the CC BY-NC-ND license (http:// creativecommons.org/licenses/by-nc-nd/4.0/).
Please cite this article in press as: Anand LK, et al., Comparison of the Supreme and the ProSeal laryngeal mask airway in patients undergoing laparoscopic cholecystectomy: A randomized controlled trial, Acta Anaesthesiologica Taiwanica (2016), http://dx.doi.org/10.1016/ j.aat.2016.03.001
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Several clinical studies comparing the LMA Supreme and LMA ProSeal show both devices have effective clinical performance, and that the airway leak pressures are equivalent in the two devices8e10 or slightly higher with the LMA ProSeal than with the LMA Supreme.11,12 The LMA Supreme has also been compared with ETT and is equally effective for routine laparoscopic procedures.13 At present, there are very limited studies comparing LMA Supreme and LMA ProSeal in patients undergoing laparoscopic cholecystectomy (LC). In this study, we compared the safety and efficacy of the LMA Supreme with those of the LMA ProSeal in patients undergoing LC by measuring the OLP, first attempt success rate, number of attempts, ease of insertion of the device and the gastric tube, fiberoptic visualization, hemodynamic and ventilatory parameters, and adverse effects such as postoperative sore throat. 2. Methods We obtained the approval of the Institutional Ethics Committee (Government Medical College and Hospital, Chandigarh, India) and written informed consent from 84 patients who had an American Society of Anesthesiologists (ASA) physical status of I or II and were aged 20e60 years old. The patients were scheduled for elective LC. Patients were excluded if they had a history of upper respiratory tract infection or had a contraindication to the use of LMA such as a known or predicted difficult airway (e.g., Modified Mallampati Class III or IV), mouth opening of <2.5 cm, body mass index >35 kg/ m2, or increased risk of regurgitation and aspiration. The study design was prospective, randomized, and controlled. Using a computer-generated random number table, the patients were randomly allocated to the LMA Supreme group (n ¼ 42) or the LMA ProSeal group (n ¼ 42). Allocation concealment was performed using sequentially numbered, coded, and sealed envelopes. An appropriately-sized Supreme or ProSeal LMA was chosen in accordance with the manufacturers' recommendations, based on a patient's weight (i.e., Size 3, 30e50 kg; Size 4, 50e70 kg; and Size 5, >70 kg).2,7 Both LMA devices were prepared for insertion with the cuff completely deflated and the dorsal surface lubricated with a water-soluble jelly. The ProSeal LMA was mounted on a dedicated metal introducer. The following standard monitors were placed before the induction of general anesthesia: continuous electrocardiogram, heart rate (HR), noninvasive blood pressure, oxygen saturation (SpO2), end-tidal carbon dioxide (EtCO2), and spirometry (Aestiva 5; DatexOhmeda, Madison, WI, USA). After obtaining intravenous (IV) access, glycopyrrolate (0.2 mg, IV) was administered. All patients received the standard anesthesia technique. After preoxygenation, morphine (0.1 mg/kg) and propofol (2.0 mg/kg) were administered. After checking for the ability to achieve adequate mask ventilation, vecuronium (0.1 mg/kg) was administered to facilitate muscle relaxation. The ProSeal LMA was inserted in the “sniffing” position by using the metal introducer and advancing the device into the hypopharynx until resistance was felt. The introducer was then removed.2 The Supreme LMA was inserted with the head in the “semisniffing” position using a smooth circular rotating movement until definite resistance was felt when the device was in the hypopharynx.7 The LMA cuff was inflated with air to the optimum intracuff pressure of 60 cmH2O using a handheld cuff manometer (VBM Medizintechnik GmbH, Sulz am Neckar, Germany). A close circle system was connected and the ventilator was adjusted to achieve effective oxygenation and ventilation using volumecontrolled positive pressure ventilation with a fresh gas flow of 3 L/min and 50% oxygen in air, tidal volume of 8e12 mL/kg, respiratory rate of 12e16 breaths/min, and inspiratory-to-expiratory time (I:E) ratio of 1:2. An effective airway was defined by the
presence of normal thoracoabdominal movement and a squarewave capnograph trace. The number of insertion attempts was recorded. A maximum of two attempts were permitted with each LMA device before the device was considered a failure. A failed attempt was defined as the removal of the device. The ease of insertion of both devices was recorded, based on the following grading: Grade 1, “very easy”; Grade 2, “easy”; Grade 3, “difficult”; and Grade 4, “very difficult”.14 The insertion time was defined as the time from picking up the LMA to the first valid capnograph trace. With the LMA in place, a single attempt was made to pass a well lubricated 14 French gauge gastric tube through the drain tube of the LMA. The insertion time was recorded. Placement of the gastric tube in the stomach was confirmed by the aspiration of gastric contents or simultaneous injection of air and epigastric auscultation. The LMA was secured to the face using adhesive tape. Anesthesia was maintained with a propofol infusion (7e10 mL/ h) and 50% oxygen in air. Once anesthesia and ventilation had stabilized, the OLP was determined by transiently stopping ventilation and closing the adjustable pressure-limiting valve with fresh gas flow of 3 L/min (for safety, the airway pressure was not allowed to exceed 40 cmH2O). This was the airway pressure generated when a leak was detected by an audible leak over the mouth. The larynx was fiberoptically viewed by passing a flexible fiberoptic bronchoscope (Pentex Corporation, Medical Division, Singapore) through the airway tube of the LMA to a predetermined position 1 cm proximal to the end of the tube, and a scoring system was used. The images of the larynx were scored as follows: Score 4, only the vocal cords were visible; Score 3, the vocal cords plus the posterior epiglottis were visible; Score 2, the vocal cords plus the anterior epiglottis were visible; and Score 1, the vocal cords were not visible.15 The intra-abdominal pressure was maintained constant at 12 mmHg by an automatic high flow carbon dioxide insufflation unit. Ventilatory variables were monitored continuously and accordingly adjusted to maintain a SpO2 of 95% and end-tidal carbon dioxide level of 35e40 mmHg. Carboperitoneum and surgical and total anesthetic time were recorded. Hemodynamic parameters [e.g., HR, mean arterial pressure (MAP)], respiratory parameters (e.g., peak airway pressure, resistance and compliance, minute ventilation), and OLP were recorded at the following time points: at the insertion of the LMA; before carboperitoneum; after carboperitoneum; 10 minutes after reverse Trendelenburg position; and after the release of carboperitoneum. In addition, the baseline and postinduction hemodynamic parameters were also recorded in both groups. After the completion of surgery, the propofol infusion was discontinued, and the residual neuromuscular block was reversed by IV neostigmine (50 mg/kg) and glycopyrrolate (10 mg/kg). The LMA was removed when the patient was awake, breathing spontaneously, and responding to verbal commands. The presence of any cough, laryngeal stridor, laryngospasm, bronchospasm, regurgitation, and the presence of blood after the removal of the LMA were recorded. A blinded observer postoperatively assessed the patients for sore throat or for any other immediate postoperative adverse effects in the postoperative anesthesia care unit at 2 hours and 24 hours postoperatively in the ward. Patients were asked about sore throat and any other adverse effects. If the answer was “yes” to any of these effects, the intensity of the complaint was assessed using a 0e10-visual analog scale in which “0” indicated absence of a sore throat and “10” indicated an extremely sore throat. All patients received the standard postoperative analgesia regime of paracetamol (1 g) and diclofenac sodium (75 mg) IV.
Please cite this article in press as: Anand LK, et al., Comparison of the Supreme and the ProSeal laryngeal mask airway in patients undergoing laparoscopic cholecystectomy: A randomized controlled trial, Acta Anaesthesiologica Taiwanica (2016), http://dx.doi.org/10.1016/ j.aat.2016.03.001
Comparison of Supreme and ProSeal LMA
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Our sample size was based on a pilot study and on the results of previous study16 in which the LMA ProSeal had an OLP of 31 cmH2O with a standard deviation of 6 cmH2O. Thirty-six patients per group were needed to detect a clinically significant difference of 15% between the two groups with a ¼ 0.05 and power of 95%. To allow for potential dropout, we recruited 42 patients per group. Statistical analysis was performed using Statistical Package for Social Sciences (SPSS Inc., version 15.0 for Windows, Chicago, IL, USA). All quantitative variables were estimated using measures of central location (i.e., mean, median) and measures of dispersion (i.e., standard deviation and standard error). The normality of data was checked by measures of skewness and KolmogoroveSmirnov tests of normality. The normally distributed data means of the two groups were compared using the Student t test. For skewed data, the ManneWhitney test was applied to the two groups. Repeated measure analysis of variance was applied for time-dependent changes. Proportions were compared using Chi-square or Fisher's exact test, whichever test was applicable. All statistical tests were two-sided and were performed at a significance level of a ¼ 0.05.
The demographic data were comparable in both groups (Table 1). All LMAs were successfully placed within two attempts. The success rate of the first attempt insertion was higher for the LMA Supreme group than for the LMA ProSeal group (95% and 85%, respectively; p < 0.05). The ease of insertion of Grade 1 (i.e., “very easy”) was better in the LMA Supreme group than in the ProSeal group (29/40 vs. 16/40; p < 0.01). Two of 40 insertions were graded as “difficult” in the LMA ProSeal group. The insertion time was lower in the LMA Supreme group than in the LMA ProSeal group (15.2 ± 4.4 seconds vs. 21.6 ± 9.1 seconds;
Table 1 Demographic data and timing.
3. Results One hundred and four patients were enrolled in the study. Twenty patients were not randomized and four patients were not studied, which left 80 patients (40 patients/group) for data analysis (Figure 1).
Enrollment
Variable
LMA Supreme Group I (N ¼ 40)
LMA ProSeal Group II (N ¼ 40)
p
Age (y) ASA I/II Sex (M/F) Height (cm) Weight (kg) BMI (kg/m2) MPG I/II Carboperitoneum time (min) Surgical time (min) Anesthesia time (min)
40.3 ± 11.4 87.5%/12.5% 15.0%/85.0% 163.0 ± 5.3 62.5 ± 10.4 23.6 ± 4.2 7.5%/92.5% 58.3 ± 29.8 74 ± 32 98 ± 37
44.1 ± 13.0 80.0%/20.0% 12.5%/87.5% 162.3 ± 6.9 61.9 ± 10.9 23.6 ± 4.3 12.5%/87.5% 56 ± 32 68 ± 31 96 ± 38
0.16 0.36 0.74 0.61 0.82 0.98 0.45 0.72 0.58 0.24
Data are presented as the mean ± the standard deviation unless otherwise denoted. ASA ¼ American Society of Anesthesiologists; BMI ¼ body mass index; MPG ¼ Mallampati grade.
104 patients assessed for eligibility
Excluded (n = 20) Not meeting inclusion criteria (n = 10) Declined to participate (n = 4) Investigators unavailable (n = 6)
84 eligible patients randomized
Allocation Allocated to LMA Supreme group (n = 42) 1 patient required intubation for surgical reasons 1 patient’s surgery postponed
Allocated to LMA Proseal group (n = 42) 1 patient converted to open cholecystectomy 1 patient intracuff pressure could not be measured Follow Up
Patients lost to follow up (n = 0) Discontinued intervention (n = 0)
Patients lost to follow up (n = 0) Discontinued intervention (n = 0) Analysis
Analyzed (n = 40) Excluded from analysis (n = 0)
Analyzed (n = 40) Excluded from analysis (n = 0)
Figure 1. Consort diagram. LMA ¼ laryngeal mask airway.
Please cite this article in press as: Anand LK, et al., Comparison of the Supreme and the ProSeal laryngeal mask airway in patients undergoing laparoscopic cholecystectomy: A randomized controlled trial, Acta Anaesthesiologica Taiwanica (2016), http://dx.doi.org/10.1016/ j.aat.2016.03.001
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p < 0.01). Passage of the gastric tube was successful in all patients. There was no statistical difference in the mean time taken to insert the gastric tube in the LMA Supreme and LMA ProSeal groups (10.0 ± 2.1 seconds and 11.3 ± 3.5 seconds, respectively; p > 0.05; Table 2). Immediately after the insertion, the mean OLP was significantly lower in the LMA Supreme group than in the LMA ProSeal group (24.9 ± 5.3 cmH2O vs. 28.4 ± 5.8 cmH2O; p < 0.01). In the LMA Supreme group, the OLP measured at different time points remained lower until the end of surgery (p < 0.05). After carboperitoneum and at 10 minutes after the reverse Trendelenburg position, the intragroup comparison showed that the mean OLP was higher from the baseline value in both groups (p < 0.05; Table 3). The fiberoptic view (Score 4) was statistically better for the LMA ProSeal group than for the LMA Supreme group (30/40 vs. 21/ 40; p < 0.01; Table 2). The mean HR and MAP measured at different time points were comparable in both groups (Figures 2 and 3, respectively). However, the intragroup comparison showed that the MAP value was higher after carboperitoneum than before carboperitoneum in both groups (p < 0.05; Figure 3). The ventilatory parameters (i.e., peak airway pressure, resistance and compliance, minute ventilation) were comparable in both groups at all time points (p > 0.05). However, in the intragroup comparison, the mean peak airway pressure and resistance were higher and compliance was lower after carboperitoneum in both groups (p < 0.05; Table 4). No episodes of laryngeal stridor, laryngospasm, bronchospasm, regurgitation were noted. Cough at the time of LMA removal was noted in five (12.5%) patients in the LMA Supreme group and in six (15%) patients in the LMA ProSeal group. Three LMAs in the Supreme group and four LMAs in the ProSeal group were bloodstained. There were no differences in the incidence of postoperative sore throat. At 24 hours, no patient reported a sore throat. 4. Discussion The present study demonstrated that the OLP was lower in the LMA Supreme group than in the LMA ProSeal group. In addition, the LMA Supreme was easier to insert and had a higher first attempt success rate and took less time to insert in comparison to the LMA ProSeal. However, the fiberoptic view score was better in the LMA ProSeal group. No significant differences existed between the two groups with respect to the insertion of the gastric tube, hemodynamic and ventilation parameters, and incidence of postoperative sore throat. The OLP or airway sealing pressure test is commonly performed to quantify the seal of the LMA and denotes the successful
placement of the device with subsequent protection of the airway.17 Furthermore, the OLP is a keystone to indicate the success of positive pressure ventilation and the appropriateness of LMA as a ventilating device, particularly for LC.6,18,19 Clinical studies have compared the LMA Supreme and LMA ProSeal for OLP with conflicting results.8e12,16,20 Some studies show no differences in OLP between the aforementioned devices.8e10 Other studies11,12,16,20 report a lower OLP (i.e., 4e8 cmH2O) with the LMA Supreme, compared to the LMA ProSeal. Similar results were observed in the present study. Belena et al20 recently compared LMA Supreme and LMA ProSeal in LC to evaluate OLP by using an experimental design that was similar to the design of the present study. However, they recorded a single OLP value immediately after the device insertion. In addition, the present study recorded the OLP before and after carboperitoneum, after positioning the patient (i.e., reverse Trendelenburg), and after the release of carboperitoneum. The OLP was lower in the LMA Supreme group than in the LMA ProSeal group at all time points. The two aforementioned devices were compared and evaluated with another second-generation supraglottic device, the i-gel supraglottic airway (Intersurgical, Ltd, Wokingham, England), in laparoscopic surgeries.21,22 A higher OLP was observed with the LMA ProSeal,21 but no difference in the OLP values was observed between the LMA Supreme and the i-gel airway.22 Maitra et al23 conducted a systematic review of the comparison of the LMA Supreme and LMA ProSeal for controlled ventilation, and concluded that the LMA ProSeal provides superior OLP in comparison to the LMA Supreme for controlled ventilation in adult patients. The higher OLP observed in LMA ProSeal may be because of its double cuff which it is made of soft silicone rubber that readily conforms to the contours of the hypopharynx, compared with the polyvinyl chloride single cuff of the LMA Supreme. In the present study, we found superior success on the first attempt with more ease and less time for insertion with the LMA Supreme than with the LMA ProSeal. We infer that the insertion time of LMA Supreme was probably shorter because of the feature of the anatomically shaped preformed airway tube with a thin wedge-shaped leading edge. By contrast, the LMA ProSeal has a dedicated metal introducer for insertion. The removal of this introducer before cuff inflation is an additional step, compared with the LMA Supreme. In addition, the LMA ProSeal has a larger, deeper, and softer bowl with a nonlinear leading edge because of the integrated esophageal drain, which poses difficulty in insertion and may further increase the insertion time. Similar results were also observed by Seet et al.12 Use of neuromuscular blocking agents may affect the performance of LMAs in relation to ease of insertion and measured OLP. Several studies have reported a higher first insertion success rate
Table 2 Laryngeal mask airway parameters.
LMA size (3/4/5) Insertion attempts (1/2) Ease of insertion grade of LMA (1/2/3/4) Insertion time of LMA (s) Fiberoptic score: 4/3/2/1 Insertion time of gastric tube (s) LMA blood-stain (yes/no) Sore throat at 0 h (%) VAS Sore throat at 2 h (%) VAS
LMA Supreme Group I (N ¼ 40)
LMA ProSeal Group II (N ¼ 40)
p
11/24/5 38/2 29/11/0/0 15.2 ± 4.4 21/10/5/4 10.0 ± 2.1 7.5% 12% 1.0 ± 4.4 17% 1.7 ± 5.3
13/23/4 34/6 16/22/2/0 21.6 ± 9.1 30/6/2/2 11.3 ± 3.5 10.0% 14% 1.1 ± 3.8 21% 2.4 ± 6.1
0.61 0.04 0.009 0.002 0.01 .079 0.50 0.13 0.05 0.06 0.42
LMA ¼ laryngeal mask airway; VAS ¼ visual analog scale.
Please cite this article in press as: Anand LK, et al., Comparison of the Supreme and the ProSeal laryngeal mask airway in patients undergoing laparoscopic cholecystectomy: A randomized controlled trial, Acta Anaesthesiologica Taiwanica (2016), http://dx.doi.org/10.1016/ j.aat.2016.03.001
Comparison of Supreme and ProSeal LMA
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Table 3 Oropharyngeal leak pressure. LMA Supreme Group I (N ¼ 40) After LMA insertion Before carboperitoneum 10 min after carboperitoneum After positioning patient After the release of carboperitoneum
24.9 26.5 29.1 29.5 26.9
± ± ± ± ±
5.3 5.5 5.2* 5.9* 5.3
LMA ProSeal Group II (N ¼ 40) 28.4 29.3 31.3 32.6 29.8
± ± ± ± ±
5.8 5.8 6.1* 5.7* 5.5
p 0.006 0.033 0.08 0.01 0.031
The oropharyngeal leak pressure is measured in cmH2O, and the data are presented as the mean ± the standard deviation. * Intragroup comparison, p < 0.05. LMA ¼ laryngeal mask airway.
Figure 2. Mean intraoperative heart rate. HR ¼ heart rate; LMA ¼ laryngeal mask airway; T0 ¼ baseline; T1 ¼ after induction; T2 ¼ After LMA insertion; T3 ¼ before carboperitoneum; T4 ¼ 10 minutes after carboperitoneum; T5 ¼ after patient positioning; T6 ¼ after release of carboperitoneum.
with the LMA Supreme.9,11,12,16,20 Three studies did not use a muscle relaxant at the time of the induction of anesthesia, and indicated that the first insertion success rate was significantly higher in the LMA Supreme group9,12,20; however, two studies did use muscle relaxants but the difference was not statistically significant.11,16 The preformed semirigid airway tube of the LMA Supreme may have facilitated its insertion. Chen et al24 reported no difference in the insertion success rate and OLP using the LMA ProSeal, irrespective of muscle relaxant use. The drain tube facilitates channeling of fluids and gases emerging from the stomach, which is particularly important in LC.25 The successful passage of the gastric tube may serve as indirect confirmation of proper functional positioning in the LMA Supreme and the LMA ProSeal. In spite of the fact that both LMAs are manufactured with different materials, we found no differences in
Figure 3. The mean intraoperative mean arterial pressure. LMA ¼ laryngeal mask airway; MAP ¼ mean arterial pressure; T0 ¼ baseline; T1 ¼ after induction; T2 ¼ after LMA insertion; T3 ¼ before carboperitoneum; T4 ¼ 10 minutes after carboperitoneum; T5 ¼ after patient positioning; T6 ¼ after release of carboperitoneum.
gastric tube placement. A similar finding has been observed in previous studies.11,20 Fiberoptic scoring has been used as a measure of anatomic alignment in studies on LMA. Higher scores may be associated with improved sealing and ventilation. In the present study, the fiberoptic grading was better in the LMA ProSeal group than in the LMA Supreme group. This may be because of the structural difference in the position of the drainage tube in the two devices. The ProSeal LMA has a drainage tube that is abreast of the ventilation channel and traverses the much deeper cuff bowl to end distally in the midline. In the LMA Supreme, the drainage tube is posterior to the ventilatory unit and traverses the cuff bowl in the midline dividing the cuff bowl into two equal parts. We believe that this structural difference may impact the visibility of the vocal cords. Similar findings were observed by previous studies that compared the two devices.8,9 Hosten et al9 observed a significant difference between the LMA ProSeal group and LMA Supreme group with full fiberscope view of vocal cords in 73% and 37% of patients, respectively. Verghese and Ramaswamy,8 had a full fiberscopic view of the vocal cords in 89% and 72% of the LMA ProSeal group and Supreme group, respectively, at the first attempt. The hemodynamic parameters were recorded at various intervals between the LMA Supreme and ProSeal groups to assess any variation in the cardiovascular response to surgical stress. In the present study, no significant statistical differences were observed between the groups. There was an increase in blood pressure because carboperitoneum was created in both groups. This could be explained by the fact that increased intra-abdominal pressure and carboperitoneum could increase blood pressures as a result of sympathetic stimulation.26 In the present study, ventilatory parameters were measured, and there was no statistical difference between the two groups. The mean peak airway pressure and resistance were increased and compliance was decreased during the period of carboperitoneum in both groups. We also observed a significant increase in the OLP after the creation of carboperitoneum in both groups compared with their baseline values. This finding could be attributed to the upward movement of the trachea because of the increase in intraabdominal pressure in an already placed and fixed LMA, which was also reported by Mishra et al27 who evaluated the effect of pneumoperitoneum and the Trendelenberg position on OLP in laparoscopic gynecological surgery. However, this proposed explanation needs further evaluation. The peak airway pressure was always lower than the OLP in both groups. Lee et al16 compared the LMA Supreme and LMA ProSeal for adequacy of ventilation and observed that the mean OLP was significantly lower in the LMA Supreme than in the LMA ProSeal, but there was no difference in their ability to provide adequate ventilation and oxygenation. Furthermore, various investigators have compared the LMA Supreme and the LMA ProSeal with ETT for ventilation efficiency in laparoscopic surgeries; they observed that the LMA Supreme and LMA ProSeal were equally effective.3,5,13
Please cite this article in press as: Anand LK, et al., Comparison of the Supreme and the ProSeal laryngeal mask airway in patients undergoing laparoscopic cholecystectomy: A randomized controlled trial, Acta Anaesthesiologica Taiwanica (2016), http://dx.doi.org/10.1016/ j.aat.2016.03.001
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Table 4 Intraoperative respiratory parameters.
After LMA insertion
Before carboperitoneum
10 min after carboperitoneum
After positioning patient
After the release of carboperitoneum
Respiratory parameters
LMA Supreme Group I (N ¼ 40)
PAP Resistance Compliance MV PAP Resistance Compliance MV PAP Resistance Compliance MV PAP Resistance Compliance MV PAP Resistance Compliance MV
16.2 7.3 45.1 5.9 18.5 8.8 39.1 6.1 23.4 10.7 28.8 7.0 23.8 11.3 27.8 6.9 19.4 7.4 40.1 7.1
± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ±
4.4 3.4 11.4 2.3 4.2 3.9 9.9 2.5 3.5 3.9 6.9 1.7 2.5 4.2 6.4 1.7 4.2 3.0 9.2 1.6
LMA ProSeal Group II (N ¼ 40) 17.2 8.2 47.3 6.2 18.7 9.7 40.9 6.2 24.1 10.7 30.8 6.9 24.3 11.3 29.7 6.7 20.3 8.3 42.0 7.1
± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ±
5.3 3.0 11.5 3.4 5.5 3.2 12.8 .6.2 4.8 3.7 8.9 .7 2.8 4.1 8.2 0.7 5.8 2.8 8.8 1.1
p 0.33 0.20 0.28 0.08 0.83 0.32 0.45 0.09 0.77 0.97 0.26 0.17 0.88 0.97 0.25 0.08 0.69 0.16 0.18 0.90
The respiratory parameters are measured in cmH2O, and the data are presented as the mean ± the standard deviation. LMA ¼ laryngeal mask airway; MV ¼ minute ventilation; PAP ¼ peak airway pressure.
Pearson and Young28 observed that the LMA Supreme is an effective airway rescue device for situations in which there is no immediate access to suitable help and an unacceptable risk of emergency intubation. High intracuff pressure in LMAs impedes pharyngeal mucosal perfusion, and this factor may lead to pharyngolaryngeal complications. In the present study, mild sore throat was observed postoperatively at 0 hour and 2 hours without any statistical difference between the two groups. The cuff pressure in our study was maintained at 60 cmH2O in both groups; therefore, there were fewer postoperative complications. Seet et al12 also observed similar results while measuring the LMA cuff pressure and pharyngolaryngeal complications in patients with manometers to limit the LMA intracuff pressure (i.e., 60 cmH2O). Mucosal injury, as indicated by blood on the device after removal, was comparable in both groups. The overall complication rate in our study was low in both groups and comparable to that reported in previous studies that evaluated the LMA Supreme and LMA ProSeal.12,16 Our study has certain limitations. First, the anesthesiologist involved was not blind to the type of LMA used, and hence provided a possible source of bias. To palliate this factor, the postoperative observer and patients were blinded to the group assignment. Second, we investigated only patients undergoing LC; however, it is worthwhile to study the safety and efficacy of LMAs in laparoscopic surgeries. 5. Conclusion The present study showed that the LMA ProSeal has a higher OLP than the LMA Supreme. However, the LMA Supreme and LMA ProSeal devices were both effective for positive pressure ventilation in LC. The LMA Supreme may be a worthy option for elective LC because of its superior first attempt success, ease of insertion with gastric access, and it is disposable. Conflicts of interest The authors declare that they have no financial or personal relationships that may have inappropriately influenced the writing of this paper.
References 1. Cook TM, Howes B. Supraglottic airway devices: recent advances. Contin Educ Anaesth Crit Care Pain 2011;2:56e61. 2. LMA ProSeal 40-use guide. Available from: http://www.teleflex.com/emea/ documentLibrary/documents/940769-000001_LMA-ProSeal-40useguide_ 1408_PDF.pdf [Accessed April 2016]. 3. Maltby JR, Beriault MT, Watson NC, Liepert D, Fick GH. The LMA-ProSeal is an effective alternative to tracheal intubation for laparoscopic cholecystectomy. Can J Anaesth 2002;49:857e62. 4. Lu PP, Brimacombe J, Yang C, Shyr M. ProSeal versus the Classic laryngeal mask airway for positive pressure ventilation during laparoscopic cholecystectomy. Br J Anaesth 2002;88:824e7. 5. Maltby JR, Beriault MT, Watson NC, Liepert DJ, Fick GH. LMA-Classic and LMAProSeal are effective alternatives to endotracheal intubation for gynecologic laparoscopy. Can J Anaesth 2003;50:71e7. 6. Natalini G, Lanza G, Rosano A, Dell'Agnolo P, Bernardini A. Standard laryngeal mask airway and LMA-ProSeal during laparoscopic surgery. J Clin Anesth 2003;15:428e32. 7. LMA Supreme. A second generation SAD with an innovative Second Seal. Available from: http://www.teleflex.com/emea/documentLibrary/documents/ 940689-000001_31817-LMA-TF-Supreme-A4_1403_PDF.pdf [Accessed April 2016]. 8. Verghese C, Ramaswamy B. LMA Supremeda new single-use LMA with gastric access: a report on its clinical efficacy. Br J Anaesth 2008;101:405e10. 9. Hosten T, Gurkan Y, Ozdamar D, Tekin M, Toker K, Solak M. A new supraglottic airway device: LMA-Supreme, comparison with LMA-ProSeal. Acta Anaesthesiol Scand 2009;53:852e7. 10. Tham HM, Tan SM, Woon KL, Zhao YD. A comparison of the Supreme laryngeal mask airway with the ProSeal laryngeal mask airway in anesthetized paralyzed adult patients: a randomized crossover study. Can J Anaesth 2010;57:672e8. 11. Eschertzhuber S, Brimacombe J, Hohlrieder M, Keller C. The laryngeal mask airway Supreme Lda single use laryngeal mask airway with an oesophageal vent. A randomised, cross-over study with the laryngeal mask airway ProSeal in paralysed, anaesthetised patients. Anaesthesia 2009;64:79e83. 12. Seet E, Rajeev S, Firoz T, Yousaf F, Wong J, Wong DT, et al. Safety and efficacy of laryngeal mask airway Supreme versus laryngeal mask airway ProSeal: a randomized controlled trial. Eur J Anaesthesiol 2010;27:602e7. 13. Abdi W, Amathieu R, Adhoum A, Poncelet C, Slavov V, Kamoun W, et al. Sparing the larynx during gynecological laparoscopy: a randomized trial comparing the LMA Supreme and the ETT. Acta Anaesthesiol Scand 2010;54:141e6. 14. Richez B, Saltel L, Banchereau F, Torrielli R, Cros AM. A new single use supraglottic airway device with a noninflatable cuff and an esophageal vent: an observational study of the i-gel. Anesth Analg 2008;106:1137e9. 15. Brimacombe J, Berry A. A proposed fiber-optic scoring system to standardize the assessment of laryngeal mask airway position. Anesth Analg 1993;76:457. 16. Lee AKY, Tey JBL, Lim Y, Sia ATH. Comparison of the single use LMA-Supreme with the reusable ProSeal LMA for anesthesia in gynaecological laparoscopic surgery. Anaesth Intensive Care 2009;37:815e9. 17. Brimacombe J. Equipment. In: Brimacombe J, editor. Laryngeal mask anesthesia. Principals and practice. 2nd ed. Philadelphia, PA: Saunders; 2005. p. 41e71.
Please cite this article in press as: Anand LK, et al., Comparison of the Supreme and the ProSeal laryngeal mask airway in patients undergoing laparoscopic cholecystectomy: A randomized controlled trial, Acta Anaesthesiologica Taiwanica (2016), http://dx.doi.org/10.1016/ j.aat.2016.03.001
Comparison of Supreme and ProSeal LMA 18. Keller C, Brimbacombe JR, Keller K, Morris R. Comparison of four methods for assessing airway sealing pressure with the laryngeal mask airway in adult patients. Br J Anaesth 1999;82:286e7. me SR, Eich C, Kazmaier S, Br€ 19. Timmermann A, Cre auer A, Graf BM, et al. Prospective clinical and fiberoptic evaluation of the supreme laryngeal mask airway. Anesthesiology 2009;110:262e5. 20. Belena JM, Nunez M, Anta D, Carnero M, Gracia JL, Ayala J, et al. Comparison of laryngeal mask airway Supreme and laryngeal mask airway ProSeal with respect to oropharyngeal leak pressure during laparoscopic cholecystectomy: a randomised controlled trial. Eur J Anaesthesiol 2013;30:119e23. 21. 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;26:451e7. 22. Teoh WH, Lee KM, Suhitharan T, Yahaya Z, Teo MM, Sia AT. Comparison of the LMA Supreme vs i-gel in paralysed patients undergoing gynaecological laparoscopic surgery with controlled ventilation. Anaesthesia 2010;65:1173e9. 23. Maitra S, Khanna P, Baidya DK. Comparison of laryngeal mask airway Supreme and laryngeal mask airway Pro-Seal for controlled ventilation during general
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24.
25. 26.
27.
28.
anesthesia in adult patients: systematic review with meta-analysis. Eur J Anaesthesiol 2014;31:266e73. Chen BZ, Tan L, Zhang L, Shang YC. Is muscle relaxant necessary in patients undergoing laparoscopic gynecological surgery with a ProSeal LMA? J Clin Anesth 2013;25:32e5. Marco AP, Yeo CJ, Rock P. Anesthesia for a patient undergoing laparoscopic cholecystectomy. Anesthesiology 1990;73:1268e70. Jain MK, Venugopal M, Tripathi CB. Use of ProSeal LMA (PLMA) for laparoscopic cholecystectomies: an ABG analysis. J Anaesth Clin Pharmacol 2010;26:87e90. Mishra SK, Sivaraman B, Balachander H, Naggappa M, Parida S, Bhat RR, et al. Effect of pneumoperitoneum and Trendelenberg position on oropharyngeal sealing pressure of I-gel and ProSeal LMA in laparoscopic gynecological surgery: a randomized controlled trial. Anesth Essays Res 2015;9:353e8 [Accessed 21 Mar 2016]. Pearson DM, Young PJ. Use of the LMA-Supreme for airway rescue. Anesthesiology 2008;109:356e7.
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Research Paper
Comparison of the Supreme and the ProSeal laryngeal mask airway in patients undergoing laparoscopic cholecystectomy: A randomized controlled trial Lakesh K. Anand 1 *, Nitika Goel 2, Manpreet Singh 1, Dheeraj Kapoor 1 1 2
Department of Anaesthesia and Intensive Care, Government Medical College and Hospital, Sector 32, Chandigarh, India Department of Anaesthesiology, All India Institute of Medical Sciences, Ansari Nagar, New Delhi, India
a r t i c l e i n f o
a b s t r a c t
Article history: Received 26 May 2015 Received in revised form 18 December 2015 Accepted 7 March 2016
Objective: The single-use LMA Supreme (Teleflex, Inc., Wayne, PA, USA) and the LMA ProSeal (Teleflex, Inc., Wayne, PA, USA) laryngeal mask airway (LMA) have similar characteristics. To date, studies have not achieved a consensus regarding the oropharyngeal leak pressure (OLP) of the LMA Supreme and LMA ProSeal, and there is little information on their efficacy in laparoscopic cholecystectomy. This study compared the safety and efficacy of the LMA Supreme and LMA ProSeal devices in patients undergoing laparoscopic cholecystectomy. Method: Eighty-four eligible consenting patients were randomly allocated to the LMA Supreme group or the LMA ProSeal group. Both groups received the standard anesthesia technique. The Supreme or ProSeal LMA was inserted, the cuff was inflated to 60 cmH2O, and the LMA position was confirmed. Anesthesia was maintained using propofol and 50% oxygen in air. A gastric tube was inserted through the drain tube of the LMA to deflate the stomach, and the first attempt success rate and insertion time were recorded. During surgery, the intra-abdominal pressure was maintained at 12 mmHg. The fiberoptic view of the larynx was determined by passing a flexible fiberoptic bronchoscope. The OLPs, success rate, insertion time, hemodynamic and respiratory parameters, and complications were recorded at different time points. Results: The mean OLP was significantly lower in the LMA Supreme group than in the LMA ProSeal group (24.9 ± 5.3 cmH2O vs. 28.4 ± 5.8 cmH2O; p < 0.01). The first attempt success rate and ease of insertion grading for LMA were higher in the Supreme group. The insertion time was lower in the Supreme group than in the ProSeal group (p < 0.01). The fiberoptic view was better with the ProSeal LMA. The hemodynamic and ventilatory parameters and postoperative sore throat were comparable in both groups. Conclusion: The LMA ProSeal has a higher OLP than the LMA Supreme. The success rate of first attempt insertion and ease of insertion were better for the LMA Supreme group and the insertion time was lower in the LMA Supreme group. The Supreme and ProSeal LMAs were both effective for positive pressure ventilation in laparoscopic cholecystectomy. Copyright © 2016, Taiwan Society of Anesthesiologists. Published by Elsevier Taiwan LLC. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
Key words: laparoscopic cholecystectomy; laryngeal mask airway; oropharyngeal leak pressure; ProSeal; Supreme
1. Introduction The contemporary laryngeal mask airway (LMA) has a built-in drain tube for gastric access, and was designed to improve ventilation, airway protection, and oropharyngeal leak pressures
* Corresponding author. Department of Anaesthesia and Intensive Care, Government Medical College and Hospital, Number 3110, Sector 48-B, Chandigarh 160047, India. E-mail address: [email protected] (L.K. Anand).
(OLPs).1 Since 2002, the LMA ProSeal (Teleflex, Inc., Wayne, PA, USA) has been compared to the endotracheal tube (ETT) and the LMA Classic device (Teleflex, Inc., Wayne, PA, USA) in patients undergoing laparoscopic surgery, and is considered an alternative airway device for a wide variety of laparoscopic procedures.2e6 The LMA Supreme (Teleflex, Inc., Wayne, PA, USA) and LMA ProSeal have similar characteristics. The curved rigid airway tube of LMA Supreme makes it easy to insert, its relatively larger polyvinyl chloride (PVC) cuff provides effective OLP, and a built-in drain tube allows reasonable deflation of the stomach; hence, it may be a practical option for laparoscopic procedures.7
http://dx.doi.org/10.1016/j.aat.2016.03.001 1875-4597/Copyright © 2016, Taiwan Society of Anesthesiologists. Published by Elsevier Taiwan LLC. This is an open access article under the CC BY-NC-ND license (http:// creativecommons.org/licenses/by-nc-nd/4.0/).
Please cite this article in press as: Anand LK, et al., Comparison of the Supreme and the ProSeal laryngeal mask airway in patients undergoing laparoscopic cholecystectomy: A randomized controlled trial, Acta Anaesthesiologica Taiwanica (2016), http://dx.doi.org/10.1016/ j.aat.2016.03.001
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Several clinical studies comparing the LMA Supreme and LMA ProSeal show both devices have effective clinical performance, and that the airway leak pressures are equivalent in the two devices8e10 or slightly higher with the LMA ProSeal than with the LMA Supreme.11,12 The LMA Supreme has also been compared with ETT and is equally effective for routine laparoscopic procedures.13 At present, there are very limited studies comparing LMA Supreme and LMA ProSeal in patients undergoing laparoscopic cholecystectomy (LC). In this study, we compared the safety and efficacy of the LMA Supreme with those of the LMA ProSeal in patients undergoing LC by measuring the OLP, first attempt success rate, number of attempts, ease of insertion of the device and the gastric tube, fiberoptic visualization, hemodynamic and ventilatory parameters, and adverse effects such as postoperative sore throat. 2. Methods We obtained the approval of the Institutional Ethics Committee (Government Medical College and Hospital, Chandigarh, India) and written informed consent from 84 patients who had an American Society of Anesthesiologists (ASA) physical status of I or II and were aged 20e60 years old. The patients were scheduled for elective LC. Patients were excluded if they had a history of upper respiratory tract infection or had a contraindication to the use of LMA such as a known or predicted difficult airway (e.g., Modified Mallampati Class III or IV), mouth opening of <2.5 cm, body mass index >35 kg/ m2, or increased risk of regurgitation and aspiration. The study design was prospective, randomized, and controlled. Using a computer-generated random number table, the patients were randomly allocated to the LMA Supreme group (n ¼ 42) or the LMA ProSeal group (n ¼ 42). Allocation concealment was performed using sequentially numbered, coded, and sealed envelopes. An appropriately-sized Supreme or ProSeal LMA was chosen in accordance with the manufacturers' recommendations, based on a patient's weight (i.e., Size 3, 30e50 kg; Size 4, 50e70 kg; and Size 5, >70 kg).2,7 Both LMA devices were prepared for insertion with the cuff completely deflated and the dorsal surface lubricated with a water-soluble jelly. The ProSeal LMA was mounted on a dedicated metal introducer. The following standard monitors were placed before the induction of general anesthesia: continuous electrocardiogram, heart rate (HR), noninvasive blood pressure, oxygen saturation (SpO2), end-tidal carbon dioxide (EtCO2), and spirometry (Aestiva 5; DatexOhmeda, Madison, WI, USA). After obtaining intravenous (IV) access, glycopyrrolate (0.2 mg, IV) was administered. All patients received the standard anesthesia technique. After preoxygenation, morphine (0.1 mg/kg) and propofol (2.0 mg/kg) were administered. After checking for the ability to achieve adequate mask ventilation, vecuronium (0.1 mg/kg) was administered to facilitate muscle relaxation. The ProSeal LMA was inserted in the “sniffing” position by using the metal introducer and advancing the device into the hypopharynx until resistance was felt. The introducer was then removed.2 The Supreme LMA was inserted with the head in the “semisniffing” position using a smooth circular rotating movement until definite resistance was felt when the device was in the hypopharynx.7 The LMA cuff was inflated with air to the optimum intracuff pressure of 60 cmH2O using a handheld cuff manometer (VBM Medizintechnik GmbH, Sulz am Neckar, Germany). A close circle system was connected and the ventilator was adjusted to achieve effective oxygenation and ventilation using volumecontrolled positive pressure ventilation with a fresh gas flow of 3 L/min and 50% oxygen in air, tidal volume of 8e12 mL/kg, respiratory rate of 12e16 breaths/min, and inspiratory-to-expiratory time (I:E) ratio of 1:2. An effective airway was defined by the
presence of normal thoracoabdominal movement and a squarewave capnograph trace. The number of insertion attempts was recorded. A maximum of two attempts were permitted with each LMA device before the device was considered a failure. A failed attempt was defined as the removal of the device. The ease of insertion of both devices was recorded, based on the following grading: Grade 1, “very easy”; Grade 2, “easy”; Grade 3, “difficult”; and Grade 4, “very difficult”.14 The insertion time was defined as the time from picking up the LMA to the first valid capnograph trace. With the LMA in place, a single attempt was made to pass a well lubricated 14 French gauge gastric tube through the drain tube of the LMA. The insertion time was recorded. Placement of the gastric tube in the stomach was confirmed by the aspiration of gastric contents or simultaneous injection of air and epigastric auscultation. The LMA was secured to the face using adhesive tape. Anesthesia was maintained with a propofol infusion (7e10 mL/ h) and 50% oxygen in air. Once anesthesia and ventilation had stabilized, the OLP was determined by transiently stopping ventilation and closing the adjustable pressure-limiting valve with fresh gas flow of 3 L/min (for safety, the airway pressure was not allowed to exceed 40 cmH2O). This was the airway pressure generated when a leak was detected by an audible leak over the mouth. The larynx was fiberoptically viewed by passing a flexible fiberoptic bronchoscope (Pentex Corporation, Medical Division, Singapore) through the airway tube of the LMA to a predetermined position 1 cm proximal to the end of the tube, and a scoring system was used. The images of the larynx were scored as follows: Score 4, only the vocal cords were visible; Score 3, the vocal cords plus the posterior epiglottis were visible; Score 2, the vocal cords plus the anterior epiglottis were visible; and Score 1, the vocal cords were not visible.15 The intra-abdominal pressure was maintained constant at 12 mmHg by an automatic high flow carbon dioxide insufflation unit. Ventilatory variables were monitored continuously and accordingly adjusted to maintain a SpO2 of 95% and end-tidal carbon dioxide level of 35e40 mmHg. Carboperitoneum and surgical and total anesthetic time were recorded. Hemodynamic parameters [e.g., HR, mean arterial pressure (MAP)], respiratory parameters (e.g., peak airway pressure, resistance and compliance, minute ventilation), and OLP were recorded at the following time points: at the insertion of the LMA; before carboperitoneum; after carboperitoneum; 10 minutes after reverse Trendelenburg position; and after the release of carboperitoneum. In addition, the baseline and postinduction hemodynamic parameters were also recorded in both groups. After the completion of surgery, the propofol infusion was discontinued, and the residual neuromuscular block was reversed by IV neostigmine (50 mg/kg) and glycopyrrolate (10 mg/kg). The LMA was removed when the patient was awake, breathing spontaneously, and responding to verbal commands. The presence of any cough, laryngeal stridor, laryngospasm, bronchospasm, regurgitation, and the presence of blood after the removal of the LMA were recorded. A blinded observer postoperatively assessed the patients for sore throat or for any other immediate postoperative adverse effects in the postoperative anesthesia care unit at 2 hours and 24 hours postoperatively in the ward. Patients were asked about sore throat and any other adverse effects. If the answer was “yes” to any of these effects, the intensity of the complaint was assessed using a 0e10-visual analog scale in which “0” indicated absence of a sore throat and “10” indicated an extremely sore throat. All patients received the standard postoperative analgesia regime of paracetamol (1 g) and diclofenac sodium (75 mg) IV.
Please cite this article in press as: Anand LK, et al., Comparison of the Supreme and the ProSeal laryngeal mask airway in patients undergoing laparoscopic cholecystectomy: A randomized controlled trial, Acta Anaesthesiologica Taiwanica (2016), http://dx.doi.org/10.1016/ j.aat.2016.03.001
Comparison of Supreme and ProSeal LMA
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Our sample size was based on a pilot study and on the results of previous study16 in which the LMA ProSeal had an OLP of 31 cmH2O with a standard deviation of 6 cmH2O. Thirty-six patients per group were needed to detect a clinically significant difference of 15% between the two groups with a ¼ 0.05 and power of 95%. To allow for potential dropout, we recruited 42 patients per group. Statistical analysis was performed using Statistical Package for Social Sciences (SPSS Inc., version 15.0 for Windows, Chicago, IL, USA). All quantitative variables were estimated using measures of central location (i.e., mean, median) and measures of dispersion (i.e., standard deviation and standard error). The normality of data was checked by measures of skewness and KolmogoroveSmirnov tests of normality. The normally distributed data means of the two groups were compared using the Student t test. For skewed data, the ManneWhitney test was applied to the two groups. Repeated measure analysis of variance was applied for time-dependent changes. Proportions were compared using Chi-square or Fisher's exact test, whichever test was applicable. All statistical tests were two-sided and were performed at a significance level of a ¼ 0.05.
The demographic data were comparable in both groups (Table 1). All LMAs were successfully placed within two attempts. The success rate of the first attempt insertion was higher for the LMA Supreme group than for the LMA ProSeal group (95% and 85%, respectively; p < 0.05). The ease of insertion of Grade 1 (i.e., “very easy”) was better in the LMA Supreme group than in the ProSeal group (29/40 vs. 16/40; p < 0.01). Two of 40 insertions were graded as “difficult” in the LMA ProSeal group. The insertion time was lower in the LMA Supreme group than in the LMA ProSeal group (15.2 ± 4.4 seconds vs. 21.6 ± 9.1 seconds;
Table 1 Demographic data and timing.
3. Results One hundred and four patients were enrolled in the study. Twenty patients were not randomized and four patients were not studied, which left 80 patients (40 patients/group) for data analysis (Figure 1).
Enrollment
Variable
LMA Supreme Group I (N ¼ 40)
LMA ProSeal Group II (N ¼ 40)
p
Age (y) ASA I/II Sex (M/F) Height (cm) Weight (kg) BMI (kg/m2) MPG I/II Carboperitoneum time (min) Surgical time (min) Anesthesia time (min)
40.3 ± 11.4 87.5%/12.5% 15.0%/85.0% 163.0 ± 5.3 62.5 ± 10.4 23.6 ± 4.2 7.5%/92.5% 58.3 ± 29.8 74 ± 32 98 ± 37
44.1 ± 13.0 80.0%/20.0% 12.5%/87.5% 162.3 ± 6.9 61.9 ± 10.9 23.6 ± 4.3 12.5%/87.5% 56 ± 32 68 ± 31 96 ± 38
0.16 0.36 0.74 0.61 0.82 0.98 0.45 0.72 0.58 0.24
Data are presented as the mean ± the standard deviation unless otherwise denoted. ASA ¼ American Society of Anesthesiologists; BMI ¼ body mass index; MPG ¼ Mallampati grade.
104 patients assessed for eligibility
Excluded (n = 20) Not meeting inclusion criteria (n = 10) Declined to participate (n = 4) Investigators unavailable (n = 6)
84 eligible patients randomized
Allocation Allocated to LMA Supreme group (n = 42) 1 patient required intubation for surgical reasons 1 patient’s surgery postponed
Allocated to LMA Proseal group (n = 42) 1 patient converted to open cholecystectomy 1 patient intracuff pressure could not be measured Follow Up
Patients lost to follow up (n = 0) Discontinued intervention (n = 0)
Patients lost to follow up (n = 0) Discontinued intervention (n = 0) Analysis
Analyzed (n = 40) Excluded from analysis (n = 0)
Analyzed (n = 40) Excluded from analysis (n = 0)
Figure 1. Consort diagram. LMA ¼ laryngeal mask airway.
Please cite this article in press as: Anand LK, et al., Comparison of the Supreme and the ProSeal laryngeal mask airway in patients undergoing laparoscopic cholecystectomy: A randomized controlled trial, Acta Anaesthesiologica Taiwanica (2016), http://dx.doi.org/10.1016/ j.aat.2016.03.001
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p < 0.01). Passage of the gastric tube was successful in all patients. There was no statistical difference in the mean time taken to insert the gastric tube in the LMA Supreme and LMA ProSeal groups (10.0 ± 2.1 seconds and 11.3 ± 3.5 seconds, respectively; p > 0.05; Table 2). Immediately after the insertion, the mean OLP was significantly lower in the LMA Supreme group than in the LMA ProSeal group (24.9 ± 5.3 cmH2O vs. 28.4 ± 5.8 cmH2O; p < 0.01). In the LMA Supreme group, the OLP measured at different time points remained lower until the end of surgery (p < 0.05). After carboperitoneum and at 10 minutes after the reverse Trendelenburg position, the intragroup comparison showed that the mean OLP was higher from the baseline value in both groups (p < 0.05; Table 3). The fiberoptic view (Score 4) was statistically better for the LMA ProSeal group than for the LMA Supreme group (30/40 vs. 21/ 40; p < 0.01; Table 2). The mean HR and MAP measured at different time points were comparable in both groups (Figures 2 and 3, respectively). However, the intragroup comparison showed that the MAP value was higher after carboperitoneum than before carboperitoneum in both groups (p < 0.05; Figure 3). The ventilatory parameters (i.e., peak airway pressure, resistance and compliance, minute ventilation) were comparable in both groups at all time points (p > 0.05). However, in the intragroup comparison, the mean peak airway pressure and resistance were higher and compliance was lower after carboperitoneum in both groups (p < 0.05; Table 4). No episodes of laryngeal stridor, laryngospasm, bronchospasm, regurgitation were noted. Cough at the time of LMA removal was noted in five (12.5%) patients in the LMA Supreme group and in six (15%) patients in the LMA ProSeal group. Three LMAs in the Supreme group and four LMAs in the ProSeal group were bloodstained. There were no differences in the incidence of postoperative sore throat. At 24 hours, no patient reported a sore throat. 4. Discussion The present study demonstrated that the OLP was lower in the LMA Supreme group than in the LMA ProSeal group. In addition, the LMA Supreme was easier to insert and had a higher first attempt success rate and took less time to insert in comparison to the LMA ProSeal. However, the fiberoptic view score was better in the LMA ProSeal group. No significant differences existed between the two groups with respect to the insertion of the gastric tube, hemodynamic and ventilation parameters, and incidence of postoperative sore throat. The OLP or airway sealing pressure test is commonly performed to quantify the seal of the LMA and denotes the successful
placement of the device with subsequent protection of the airway.17 Furthermore, the OLP is a keystone to indicate the success of positive pressure ventilation and the appropriateness of LMA as a ventilating device, particularly for LC.6,18,19 Clinical studies have compared the LMA Supreme and LMA ProSeal for OLP with conflicting results.8e12,16,20 Some studies show no differences in OLP between the aforementioned devices.8e10 Other studies11,12,16,20 report a lower OLP (i.e., 4e8 cmH2O) with the LMA Supreme, compared to the LMA ProSeal. Similar results were observed in the present study. Belena et al20 recently compared LMA Supreme and LMA ProSeal in LC to evaluate OLP by using an experimental design that was similar to the design of the present study. However, they recorded a single OLP value immediately after the device insertion. In addition, the present study recorded the OLP before and after carboperitoneum, after positioning the patient (i.e., reverse Trendelenburg), and after the release of carboperitoneum. The OLP was lower in the LMA Supreme group than in the LMA ProSeal group at all time points. The two aforementioned devices were compared and evaluated with another second-generation supraglottic device, the i-gel supraglottic airway (Intersurgical, Ltd, Wokingham, England), in laparoscopic surgeries.21,22 A higher OLP was observed with the LMA ProSeal,21 but no difference in the OLP values was observed between the LMA Supreme and the i-gel airway.22 Maitra et al23 conducted a systematic review of the comparison of the LMA Supreme and LMA ProSeal for controlled ventilation, and concluded that the LMA ProSeal provides superior OLP in comparison to the LMA Supreme for controlled ventilation in adult patients. The higher OLP observed in LMA ProSeal may be because of its double cuff which it is made of soft silicone rubber that readily conforms to the contours of the hypopharynx, compared with the polyvinyl chloride single cuff of the LMA Supreme. In the present study, we found superior success on the first attempt with more ease and less time for insertion with the LMA Supreme than with the LMA ProSeal. We infer that the insertion time of LMA Supreme was probably shorter because of the feature of the anatomically shaped preformed airway tube with a thin wedge-shaped leading edge. By contrast, the LMA ProSeal has a dedicated metal introducer for insertion. The removal of this introducer before cuff inflation is an additional step, compared with the LMA Supreme. In addition, the LMA ProSeal has a larger, deeper, and softer bowl with a nonlinear leading edge because of the integrated esophageal drain, which poses difficulty in insertion and may further increase the insertion time. Similar results were also observed by Seet et al.12 Use of neuromuscular blocking agents may affect the performance of LMAs in relation to ease of insertion and measured OLP. Several studies have reported a higher first insertion success rate
Table 2 Laryngeal mask airway parameters.
LMA size (3/4/5) Insertion attempts (1/2) Ease of insertion grade of LMA (1/2/3/4) Insertion time of LMA (s) Fiberoptic score: 4/3/2/1 Insertion time of gastric tube (s) LMA blood-stain (yes/no) Sore throat at 0 h (%) VAS Sore throat at 2 h (%) VAS
LMA Supreme Group I (N ¼ 40)
LMA ProSeal Group II (N ¼ 40)
p
11/24/5 38/2 29/11/0/0 15.2 ± 4.4 21/10/5/4 10.0 ± 2.1 7.5% 12% 1.0 ± 4.4 17% 1.7 ± 5.3
13/23/4 34/6 16/22/2/0 21.6 ± 9.1 30/6/2/2 11.3 ± 3.5 10.0% 14% 1.1 ± 3.8 21% 2.4 ± 6.1
0.61 0.04 0.009 0.002 0.01 .079 0.50 0.13 0.05 0.06 0.42
LMA ¼ laryngeal mask airway; VAS ¼ visual analog scale.
Please cite this article in press as: Anand LK, et al., Comparison of the Supreme and the ProSeal laryngeal mask airway in patients undergoing laparoscopic cholecystectomy: A randomized controlled trial, Acta Anaesthesiologica Taiwanica (2016), http://dx.doi.org/10.1016/ j.aat.2016.03.001
Comparison of Supreme and ProSeal LMA
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Table 3 Oropharyngeal leak pressure. LMA Supreme Group I (N ¼ 40) After LMA insertion Before carboperitoneum 10 min after carboperitoneum After positioning patient After the release of carboperitoneum
24.9 26.5 29.1 29.5 26.9
± ± ± ± ±
5.3 5.5 5.2* 5.9* 5.3
LMA ProSeal Group II (N ¼ 40) 28.4 29.3 31.3 32.6 29.8
± ± ± ± ±
5.8 5.8 6.1* 5.7* 5.5
p 0.006 0.033 0.08 0.01 0.031
The oropharyngeal leak pressure is measured in cmH2O, and the data are presented as the mean ± the standard deviation. * Intragroup comparison, p < 0.05. LMA ¼ laryngeal mask airway.
Figure 2. Mean intraoperative heart rate. HR ¼ heart rate; LMA ¼ laryngeal mask airway; T0 ¼ baseline; T1 ¼ after induction; T2 ¼ After LMA insertion; T3 ¼ before carboperitoneum; T4 ¼ 10 minutes after carboperitoneum; T5 ¼ after patient positioning; T6 ¼ after release of carboperitoneum.
with the LMA Supreme.9,11,12,16,20 Three studies did not use a muscle relaxant at the time of the induction of anesthesia, and indicated that the first insertion success rate was significantly higher in the LMA Supreme group9,12,20; however, two studies did use muscle relaxants but the difference was not statistically significant.11,16 The preformed semirigid airway tube of the LMA Supreme may have facilitated its insertion. Chen et al24 reported no difference in the insertion success rate and OLP using the LMA ProSeal, irrespective of muscle relaxant use. The drain tube facilitates channeling of fluids and gases emerging from the stomach, which is particularly important in LC.25 The successful passage of the gastric tube may serve as indirect confirmation of proper functional positioning in the LMA Supreme and the LMA ProSeal. In spite of the fact that both LMAs are manufactured with different materials, we found no differences in
Figure 3. The mean intraoperative mean arterial pressure. LMA ¼ laryngeal mask airway; MAP ¼ mean arterial pressure; T0 ¼ baseline; T1 ¼ after induction; T2 ¼ after LMA insertion; T3 ¼ before carboperitoneum; T4 ¼ 10 minutes after carboperitoneum; T5 ¼ after patient positioning; T6 ¼ after release of carboperitoneum.
gastric tube placement. A similar finding has been observed in previous studies.11,20 Fiberoptic scoring has been used as a measure of anatomic alignment in studies on LMA. Higher scores may be associated with improved sealing and ventilation. In the present study, the fiberoptic grading was better in the LMA ProSeal group than in the LMA Supreme group. This may be because of the structural difference in the position of the drainage tube in the two devices. The ProSeal LMA has a drainage tube that is abreast of the ventilation channel and traverses the much deeper cuff bowl to end distally in the midline. In the LMA Supreme, the drainage tube is posterior to the ventilatory unit and traverses the cuff bowl in the midline dividing the cuff bowl into two equal parts. We believe that this structural difference may impact the visibility of the vocal cords. Similar findings were observed by previous studies that compared the two devices.8,9 Hosten et al9 observed a significant difference between the LMA ProSeal group and LMA Supreme group with full fiberscope view of vocal cords in 73% and 37% of patients, respectively. Verghese and Ramaswamy,8 had a full fiberscopic view of the vocal cords in 89% and 72% of the LMA ProSeal group and Supreme group, respectively, at the first attempt. The hemodynamic parameters were recorded at various intervals between the LMA Supreme and ProSeal groups to assess any variation in the cardiovascular response to surgical stress. In the present study, no significant statistical differences were observed between the groups. There was an increase in blood pressure because carboperitoneum was created in both groups. This could be explained by the fact that increased intra-abdominal pressure and carboperitoneum could increase blood pressures as a result of sympathetic stimulation.26 In the present study, ventilatory parameters were measured, and there was no statistical difference between the two groups. The mean peak airway pressure and resistance were increased and compliance was decreased during the period of carboperitoneum in both groups. We also observed a significant increase in the OLP after the creation of carboperitoneum in both groups compared with their baseline values. This finding could be attributed to the upward movement of the trachea because of the increase in intraabdominal pressure in an already placed and fixed LMA, which was also reported by Mishra et al27 who evaluated the effect of pneumoperitoneum and the Trendelenberg position on OLP in laparoscopic gynecological surgery. However, this proposed explanation needs further evaluation. The peak airway pressure was always lower than the OLP in both groups. Lee et al16 compared the LMA Supreme and LMA ProSeal for adequacy of ventilation and observed that the mean OLP was significantly lower in the LMA Supreme than in the LMA ProSeal, but there was no difference in their ability to provide adequate ventilation and oxygenation. Furthermore, various investigators have compared the LMA Supreme and the LMA ProSeal with ETT for ventilation efficiency in laparoscopic surgeries; they observed that the LMA Supreme and LMA ProSeal were equally effective.3,5,13
Please cite this article in press as: Anand LK, et al., Comparison of the Supreme and the ProSeal laryngeal mask airway in patients undergoing laparoscopic cholecystectomy: A randomized controlled trial, Acta Anaesthesiologica Taiwanica (2016), http://dx.doi.org/10.1016/ j.aat.2016.03.001
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L.K. Anand et al.
Table 4 Intraoperative respiratory parameters.
After LMA insertion
Before carboperitoneum
10 min after carboperitoneum
After positioning patient
After the release of carboperitoneum
Respiratory parameters
LMA Supreme Group I (N ¼ 40)
PAP Resistance Compliance MV PAP Resistance Compliance MV PAP Resistance Compliance MV PAP Resistance Compliance MV PAP Resistance Compliance MV
16.2 7.3 45.1 5.9 18.5 8.8 39.1 6.1 23.4 10.7 28.8 7.0 23.8 11.3 27.8 6.9 19.4 7.4 40.1 7.1
± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ±
4.4 3.4 11.4 2.3 4.2 3.9 9.9 2.5 3.5 3.9 6.9 1.7 2.5 4.2 6.4 1.7 4.2 3.0 9.2 1.6
LMA ProSeal Group II (N ¼ 40) 17.2 8.2 47.3 6.2 18.7 9.7 40.9 6.2 24.1 10.7 30.8 6.9 24.3 11.3 29.7 6.7 20.3 8.3 42.0 7.1
± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ±
5.3 3.0 11.5 3.4 5.5 3.2 12.8 .6.2 4.8 3.7 8.9 .7 2.8 4.1 8.2 0.7 5.8 2.8 8.8 1.1
p 0.33 0.20 0.28 0.08 0.83 0.32 0.45 0.09 0.77 0.97 0.26 0.17 0.88 0.97 0.25 0.08 0.69 0.16 0.18 0.90
The respiratory parameters are measured in cmH2O, and the data are presented as the mean ± the standard deviation. LMA ¼ laryngeal mask airway; MV ¼ minute ventilation; PAP ¼ peak airway pressure.
Pearson and Young28 observed that the LMA Supreme is an effective airway rescue device for situations in which there is no immediate access to suitable help and an unacceptable risk of emergency intubation. High intracuff pressure in LMAs impedes pharyngeal mucosal perfusion, and this factor may lead to pharyngolaryngeal complications. In the present study, mild sore throat was observed postoperatively at 0 hour and 2 hours without any statistical difference between the two groups. The cuff pressure in our study was maintained at 60 cmH2O in both groups; therefore, there were fewer postoperative complications. Seet et al12 also observed similar results while measuring the LMA cuff pressure and pharyngolaryngeal complications in patients with manometers to limit the LMA intracuff pressure (i.e., 60 cmH2O). Mucosal injury, as indicated by blood on the device after removal, was comparable in both groups. The overall complication rate in our study was low in both groups and comparable to that reported in previous studies that evaluated the LMA Supreme and LMA ProSeal.12,16 Our study has certain limitations. First, the anesthesiologist involved was not blind to the type of LMA used, and hence provided a possible source of bias. To palliate this factor, the postoperative observer and patients were blinded to the group assignment. Second, we investigated only patients undergoing LC; however, it is worthwhile to study the safety and efficacy of LMAs in laparoscopic surgeries. 5. Conclusion The present study showed that the LMA ProSeal has a higher OLP than the LMA Supreme. However, the LMA Supreme and LMA ProSeal devices were both effective for positive pressure ventilation in LC. The LMA Supreme may be a worthy option for elective LC because of its superior first attempt success, ease of insertion with gastric access, and it is disposable. Conflicts of interest The authors declare that they have no financial or personal relationships that may have inappropriately influenced the writing of this paper.
References 1. Cook TM, Howes B. Supraglottic airway devices: recent advances. Contin Educ Anaesth Crit Care Pain 2011;2:56e61. 2. LMA ProSeal 40-use guide. Available from: http://www.teleflex.com/emea/ documentLibrary/documents/940769-000001_LMA-ProSeal-40useguide_ 1408_PDF.pdf [Accessed April 2016]. 3. Maltby JR, Beriault MT, Watson NC, Liepert D, Fick GH. The LMA-ProSeal is an effective alternative to tracheal intubation for laparoscopic cholecystectomy. Can J Anaesth 2002;49:857e62. 4. Lu PP, Brimacombe J, Yang C, Shyr M. ProSeal versus the Classic laryngeal mask airway for positive pressure ventilation during laparoscopic cholecystectomy. Br J Anaesth 2002;88:824e7. 5. Maltby JR, Beriault MT, Watson NC, Liepert DJ, Fick GH. LMA-Classic and LMAProSeal are effective alternatives to endotracheal intubation for gynecologic laparoscopy. Can J Anaesth 2003;50:71e7. 6. Natalini G, Lanza G, Rosano A, Dell'Agnolo P, Bernardini A. Standard laryngeal mask airway and LMA-ProSeal during laparoscopic surgery. J Clin Anesth 2003;15:428e32. 7. LMA Supreme. A second generation SAD with an innovative Second Seal. Available from: http://www.teleflex.com/emea/documentLibrary/documents/ 940689-000001_31817-LMA-TF-Supreme-A4_1403_PDF.pdf [Accessed April 2016]. 8. Verghese C, Ramaswamy B. LMA Supremeda new single-use LMA with gastric access: a report on its clinical efficacy. Br J Anaesth 2008;101:405e10. 9. Hosten T, Gurkan Y, Ozdamar D, Tekin M, Toker K, Solak M. A new supraglottic airway device: LMA-Supreme, comparison with LMA-ProSeal. Acta Anaesthesiol Scand 2009;53:852e7. 10. Tham HM, Tan SM, Woon KL, Zhao YD. A comparison of the Supreme laryngeal mask airway with the ProSeal laryngeal mask airway in anesthetized paralyzed adult patients: a randomized crossover study. Can J Anaesth 2010;57:672e8. 11. Eschertzhuber S, Brimacombe J, Hohlrieder M, Keller C. The laryngeal mask airway Supreme Lda single use laryngeal mask airway with an oesophageal vent. A randomised, cross-over study with the laryngeal mask airway ProSeal in paralysed, anaesthetised patients. Anaesthesia 2009;64:79e83. 12. Seet E, Rajeev S, Firoz T, Yousaf F, Wong J, Wong DT, et al. Safety and efficacy of laryngeal mask airway Supreme versus laryngeal mask airway ProSeal: a randomized controlled trial. Eur J Anaesthesiol 2010;27:602e7. 13. Abdi W, Amathieu R, Adhoum A, Poncelet C, Slavov V, Kamoun W, et al. Sparing the larynx during gynecological laparoscopy: a randomized trial comparing the LMA Supreme and the ETT. Acta Anaesthesiol Scand 2010;54:141e6. 14. Richez B, Saltel L, Banchereau F, Torrielli R, Cros AM. A new single use supraglottic airway device with a noninflatable cuff and an esophageal vent: an observational study of the i-gel. Anesth Analg 2008;106:1137e9. 15. Brimacombe J, Berry A. A proposed fiber-optic scoring system to standardize the assessment of laryngeal mask airway position. Anesth Analg 1993;76:457. 16. Lee AKY, Tey JBL, Lim Y, Sia ATH. Comparison of the single use LMA-Supreme with the reusable ProSeal LMA for anesthesia in gynaecological laparoscopic surgery. Anaesth Intensive Care 2009;37:815e9. 17. Brimacombe J. Equipment. In: Brimacombe J, editor. Laryngeal mask anesthesia. Principals and practice. 2nd ed. Philadelphia, PA: Saunders; 2005. p. 41e71.
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Please cite this article in press as: Anand LK, et al., Comparison of the Supreme and the ProSeal laryngeal mask airway in patients undergoing laparoscopic cholecystectomy: A randomized controlled trial, Acta Anaesthesiologica Taiwanica (2016), http://dx.doi.org/10.1016/ j.aat.2016.03.001