Introduction: Supraglottic devices have mostly eliminated the need of hemodynamically stressful routine endotracheal intubation for ambulatory surgeries. We aimed to compare hemodynamics- like blood pressure (BP) and heart rate (HR) alterations caused by stress response due to i-gel™ and LMA-ProSeal™ usage in Day care surgeries. Secondary outcomes included ease of insertion, time and number of attempts for the placement of devices.
Materials and Methods: From April 2008 to July 2009, Sixty adult ASA I-II patients of either sex, aged 20-30, were randomly allocated into two groups (Group i-gel (n=30) receiving i-gel and Group PLMA (n=30) receiving LMA-ProSeal for airway maintenance) undergoing day care surgical procedures under general anaesthesia (GA).The ease of insertion and time taken for placement of device, postoperative complications were assessed. Haemodynamic parameters (HR, BP) were noted. It was a prospective, double blinded, and randomized controlled study. Parametric data were analyzed with the unpaired t-test and non-parametric data were analyzed with the Chi-square test. Unless otherwise stated, data are presented as mean (+ SD). p <0.05 was considered statistically significant.
Results: Demographically both the groups were similar. i-gel was more easily inserted than LMA-ProSeal (90% vs. 83.33% respectively). i-gel insertion time was shorter than PLMA (14.9 vs. 20.0 sec respectively) and was statistically significant. Hemodynamics (HR, BP) were less altered in i-gel than PLMA and the results were statistically significant (p <0.05).
Conclusion: i-Gel; a relatively newer and cheap supraglottic device; insertion is easier and quicker as well as hemodynamically less stressful when compared with LMA—ProSeal in a day care setting.
i-gel™ (i-gel); LMA—ProSeal™ (PLMA); Ambulatory (day care surgery); ASA (American Society of Anaesthesiologists); Blood pressure (BP) and Heart rate (HR)
The newest variation of the i-gel supraglottic airway is a pediatric version.
This study was designed to investigate the usefulness of the size 2 i-gel compared with the ProSeal laryngeal mask airway (PLMA) and classic laryngeal mask airway (cLMA) of the same size in anesthetized, paralyzed children.
Settings and design:
A prospective, randomized, single-blinded study was conducted in a tertiary care teaching hospital.
Ninety ASA grade I–II patients undergoing lower abdominal, inguinal and orthopedic surgery were included in this prospective study. The patients were randomly assigned to the i-gel, PLMA and cLMA groups (30 patients in each group). Size 2 supraglottic airway was inserted according to the assigned group. We assessed ease of insertion, hemodynamic data, oropharyngeal sealing pressure and postoperative complications.
There were no differences in the demographic and hemodynamic data among the three groups. The airway leak pressure of the i-gel group (27.1±2.6 cmH2O) was significantly higher than that of the PLMA group (22.73±1.2 cmH2O) and the cLMA group (23.63±2.3 cmH2O). The success rates for first attempt of insertion were similar among the three devices. There were no differences in the incidence of postoperative airway trauma, sore throat or hoarse cry in the three groups.
Hemodynamic parameters, ease of insertion and postoperative complications were comparable among the i-gel, PLMA and cLMA groups, but airway sealing pressure was significantly higher in the i-gel group.
Classic laryngeal mask airway; i-gel; pediatric patients; ProSeal laryngeal mask airway
ProSeal laryngeal mask airway (PLMA) efficacy in pediatric anesthesia.
The aim of this study was to compare PLMA size 2 and 2½ in anesthetized paralyzed pediatric patients weighing 20–30 kg undergoing elective surgery.
Settings and Design:
A prospective randomized study was conducted in a tertiary care teaching hospital.
Materials and Methods:
A total of 60 American Society of Anesthesiologists I pediatric patients of either sex having body weight between 20 and 30 kg undergoing elective surgeries were randomly allocated to PLMA of either size 2 or 2½. Standardized anesthetic technique with propofol, sevoflurane, vecuronium bromide, nitrous oxide was used in all patients. Parameters such as number of attempts, time to achieve an effective airway, hemodynamic parameters, drain tube test, oropharyngeal leak pressure (OPL), gastric tube placement, and postoperative adverse events were noted. Statistical analysis by Kolmogorov-Smirnov analysis, Mann-Whitney U-test, Student's t-test, Wilk's lambda test and power analysis was done.
There were no significant differences in demographic variables, ease of insertion and ventilation, number of insertion attempts, hemodynamics, and postoperative complications. OPLs were slightly higher in PLMA size 2½ (27.38 ± 6.36 vs. 22.62 ± 2.85 cm H2O, respectively; P = 0.001) than size 2.
Both PLMA size 2 and 2½ provided adequate seal pressures that would allow positive pressure ventilation in healthy children. Thus PLMA of either size 2 or 2½ can be used as a reliable airway device in children weighing 20-30 kg.
Anesthetized; paralyzed; pediatric; ProSeal laryngeal mask airway; weight
We compared i-gel and ProSeal laryngeal mask airway (PLMA) regarding time taken for insertion, effective seal, fiberoptic view of larynx, ease of Ryle's tube insertion, and postoperative sore throat assessment.
Materials and Methods:
In a prospective, randomized manner, 48 adult patients of American Society of Anesthesiologists I-II of either gender between 18 and 60 years presenting for a short surgical procedure were assigned to undergo surgery under general anesthesia on spontaneous ventilation using either the i-gel or PLMA. An experienced nonblinded anesthesiologist inserted appropriate sized i-gel or PLMA in patients using standard insertion technique and assessed the intraoperative findings of the study regarding regarding time taken for respective device insertion, effective seal, fiberoptic view of larynx, ease of Ryle's tube insertion, and postoperative sore throat assessment. Postoperative assessment of sore throat was done by blinded anesthesia resident.
The time required for insertion of i-gel was lesser (21.98 ± 5.42 and 30.60 ± 8.51 s in Group I and Group P, respectively; P = 0.001). Numbers of attempts for successful insertions were comparable and in majority, device was inserted in first attempt. The mean airway leak pressures were comparable. However, there were more number of patients in Group P who had airway leak pressure >20 cm H2O. The fiberoptic view of glottis, ease of Ryle's tube insertion, and incidence of complications were comparable.
Time required for successful insertion of i-gel was less in adult patients undergoing short surgical procedure under general anesthesia on spontaneous ventilation. Patients with airway leak pressure >20 cm H2O were more in PLMA group which indicates its better suitability for controlled ventilation.
Airway leak pressure; i-gel; PLMA; time for insertion
The aim of this study was to compare the streamlined liner of the pharynx airway (SLIPA), a new supraglottic airway device (SGA), with the laryngeal mask airway ProSeal™ (PLMA) during general anesthesia.
Sixty patients were randomly allocated to two groups; a PLMA group (n = 30) or a SLIPA group (n = 30). Ease of use, first insertion success rate, hemodynamic responses to insertion, ventilatory efficiency and positioning confirmed by fiberoptic bronchoscopy were assessed. Lung mechanics data were collected with side stream spirometry at 10 minutes after insertion. We also compared the incidence of blood stain, incidence and severity of postoperative sore throat and other complications.
First attempt success rates were 93.3% and 73.3%, and mean insertion time was 7.3 sec and 10.5 sec in PLMA and SLIPA. There was a significant rise in all of hemodynamic response from the pre-insertion value at one minute following insertion of SLIPA. But, insertion of PLMA was no significant rise in hemodynamic response. There was no statistically significant difference in the mean maximum sealing pressure, gas leakage, lung mechanics data, gastric distension, postoperative sore throat and other complication between the two groups. Blood stain were noted on the surface of the device in 40% (n = 12) in the SLIPA vs. 6.7% (n = 2) in the PLMA.
The SLIPA is a useful alternative to the PLMA and have comparable efficacy and complication rates. If we acquire the skill to use, SLIPA may be considered as primary SGA devices during surgery under general anesthesia.
Airway; Anesthesia; PLMA; SLIPA; Supraglottic airway
To compare insertion characteristics of 2 different supraglottic devices [I-gel and Proseal laryngeal mask airway (PLMA)] and to observe any associated complications.
This prospective, randomized study was conducted in 80 patients [Group I - I-gel insertion (n = 40) and Group P - LMA Proseal insertion (n =40)] of ASA grades I/II, of either sex in the age group 18-65 years. Both groups were compared with respect to ease of insertion, insertion attempts, fiberoptic assessment, airway sealing pressure, ease of gastric tube placement, and other complications.
Materials and Methods:
All patients were asked to fast overnight. Patients were given alprazolam 0.25 mg orally at 10 p.m. the night before surgery and again 2 hours prior to surgery with 1-2 sips of water. Glycopyrrolate 0.2 mg, metoclopramide 10 mg, and ranitidine 50 mg were administered intravenously to the patients 45 minutes prior to the surgery. Once adequate depth of anesthesia was achieved either of the 2 devices, selected using a random computerized table, was inserted by an experienced anesthesiologist. In group I, I-gel was inserted and in patients of group P, PLMA was inserted.
Student t-test and Mann-Whitney test were employed to compare the means; for categorical variables, Chi-square test was used.
Mean insertion time for the I-gel (11.12 ± 1.814 sec) was significantly lower than that of the PLMA (15.13 ± 2.91 sec) (P = 0.001). I-gel was easier to insert with a better anatomic fit. Mean airway sealing pressure in the PLMA group (29.55 ± 3.53 cm H2O) was significantly higher than in the I-gel group (26.73 ± 2.52 cm H2O; P = 0.001). Ease of gastric tube insertion was significantly higher in the I-gel group (P = 0.001). Incidence of blood staining of the device, sore throat and dysphagia were observed more in PLMA group. No other complications were observed in either of the groups.
Airway sealing; cuff pressure; fiberoptic; I-gel; insertion; leak; proseal laryngeal mask airway
Supraglottic airway devices have been used as an alternative to tracheal intubation during laparoscopic surgery.
The study was designed to compare the efficacy of Streamlined Liner of the Pharynx Airway (SLIPA) for positive pressure ventilation and postoperative complications with the Laryngeal Mask Airway ProSeal (PLMA) for patients undergoing lower abdominal laparoscopies under general anesthesia with controlled ventilation.
Settings and Design:
Prospective, crossover randomized controlled trial performed on patients undergoing lower abdominal laparoscopic surgeries.
A total of 120 patients undergoing lower abdominal laparoscopic surgeries were randomly allocated into two equal groups; PLMA and SLIPA groups. Number of intubation attempts, insertion time, ease of insertion, and fiberoptic bronchoscopic view were recorded. Lung mechanics data were collected 5 minutes after securing the airway, then after abdominal insufflation. Blood traces and regurgitation were checked for; postoperative sore throat and other complications were recorded.
Arithmetic mean and standard deviation values were calculated and statistical analyses were performed for each group. Independent sample t-test was used to compare continuous variables exhibiting normal distribution, and Chi-squared test for noncontinuous variables. P value <0.05 was considered significant.
Insertion time, first insertion success rate, and ease of insertion were comparable in both groups. Fiberoptic bronchoscopic view was significantly better and epiglottic downfolding was significantly lower in SLIPA group. Sealing pressure and lung mechanics were similar. Gastric distension was not observed in both groups. Postoperative sore throat was significantly higher in PACU in PLMA group. Blood traces on the device were significantly more in SLIPA group.
SLIPA can be used as a useful alternative to PLMA in patients undergoing lower abdominal laparoscopic surgery with muscle relaxant and controlled ventilation.
Laparoscopic surgery; proseal lma; streamlined liner of the pharynx airway; supraglottic airway devices
The relatively recently developed I-gel (Intersurgical Ltd., Workingham, England) is a supraglottic airway device designed for single-use that, unlike conventional LMAs, does not require an inflatable cuff. In addition, the I-gel, much like the Proseal LMA (PLMA), has a gastric drainage tube associated with an upper tube for decompression of the stomach, thereby avoiding acid reflux and decreasing the risk of pulmonary absorption. The purpose of this study was to compare PLMA and I-gel devices in patients undergoing gynecological laparoscopy based on sealing pressure before and during pneumoperitoneum, insertion time, and gas exchange.
Following Institutional Review Board approval and written informed consent, 30 adult patients were randomly allocated to one of two groups (the PLMA or I-gel group). In each case, insertion time and number of attempts were recorded. After successful insertion, airway leak pressure was measured.
Successful insertion and mechanical ventilation with both supraglottic airway devices was achieved on the first attempt in all 30 patients, and there were no significant differences with respect to insertion time. Likewise, leak pressure did not vary significantly either between or within groups after CO2 insufflation. In addition, differences between leak volume and leak fraction between groups were not significant.
The results of our study indicate that the I-gel is a reasonable alternative to the PLMA for controlled ventilation during laparoscopic gynecologic surgery.
The laryngeal mask airway (LMA) is a supraglottic airway management device. The LMA is preferred for airway management in paediatric patients for short duration surgical procedures. The recently introduced ProSeal (PLMA), a modification of Classic LMA, has a gastric drainage tube placed lateral to main airway tube which allows the regurgitated gastric contents to bypass the glottis and prevents the pulmonary aspiration. This study was done to compare the efficacy of ProSeal LMA with an endotracheal tube in paediatric patients with respect to number of attempts for placement of devices, haemodynamic responses and perioperative respiratory complications. Sixty children, ASA I and II, weighing 10-20 kg between 2 and 8 years of age group of either sex undergoing elective ophthalmological and lower abdominal surgeries of 30-60 min duration, randomly divided into two groups of 30 patients each were studied. The number of attempts for endotracheal intubation was less than the placement of PLMA. Haemodynamic responses were significantly higher (P<0.05) after endotracheal intubation as compared to the placement of PLMA. There were no significant differences in mean SpO2 (%) and EtCO2 levels recorded at different time intervals between the two groups. The incidence of post-operative respiratory complications cough and bronchospasm was higher after extubation than after removal of PLMA. The incidence of soft tissue trauma was noted to be higher for PLMA after its removal. There were no incidences of aspiration and hoarseness/sore throat in either group. It is concluded that ProSeal LMA can be safely considered as a suitable and effective alternative to endotracheal intubation in paediatric patients for short duration surgical procedures.
ET tube; haemodynamic response; PLMA
Background and Aims:
Supraglottic airway devices have been established in clinical anesthesia practice and have been previously shown to be safe and efficient. The objective of this prospective, randomized trial was to compare I-Gel with LMA-Proseal in anesthetized spontaneously breathing patients.
Material and Methods:
Sixty patients undergoing short surgical procedures were randomly assigned to I-gel (Group I) or LMA- Proseal (Group P). Anesthesia was induced with standard doses of propofol and the supraglottic airway device was inserted. We compared the ease and time required for insertion, airway sealing pressure and adverse events.
There were no significant differences in demographic and hemodynamic data. I-gel was significantly easier to insert than LMA-Proseal (P < 0.05) (Chi-square test). The mean time for insertion was more with Group P (41 + 09.41 secs) than with Group I (29.53 + 08.23 secs) (P < 0.05). Although the airway sealing pressure was significantly higher with Group P (25.73 + 02.21 cm of H2O), the airway sealing pressure of Group I (20.07 + 02.94 cm of H2O) was very well within normal limit (Student's t test). The success rate of first attempt insertion was more with Group I (P < 0.05). There was no evidence of airway trauma, regurgitation and aspiration. Sore throat was significantly more evident in Group P.
I-Gel is a innovative supraglottic device with acceptable airway sealing pressure, easier to insert, less traumatic with lower incidence of sore throat. Hence I-Gel can be a good alternative to LMA-Proseal.
Airway sealing pressure; I-gel; laryngeal mask airway-Proseal; supraglottic airway device
i-gel™ and the ProSeal™ laryngeal mask airway (PLMA) are two supraglottic airway devices with gastric channel used for airway maintenance in anesthesia. This study was designed to evaluate the efficacy of i-gel compared with PLMA for airway maintenance in pediatric patients under general anesthesia with controlled ventilation.
Materials and Methods:
A total of 60 American Society of Anesthesiologists physical status 1 and 2 patients were included in the study and randomized to either i-gel or PLMA group. After induction of anesthesia using a standardized protocol for all the patients, one of supraglottic airway devices was inserted. Insertion parameters, ease of gastric tube insertion and fiber-optic scoring of the glottis were noted. Airway parameters such as end-tidal carbon dioxide (EtCO2), peak airway pressures and leak airway pressures were noted. Patients were observed for any complications in the first 12 h of the post-operative period.
Both groups were comparable in terms of ease of insertion, number of attempts and other insertion parameters. Ease of gastric tube insertion, EtCO2, airway pressures (peak and leak airway pressure) and fiber-optic view of the glottis were comparable in both groups. There were no clinically significant complications in the first 12 h of the post-operative period.
i-gel is as effective as PLMA in pediatric patients under controlled ventilation.
Controlled ventilation; fiber-optic view of glottis; leak airway pressure; peak airway pressure; pediatric i-gel airway; ProSeal™ laryngeal mask
To compare the insertion time, ease of device insertion, ease of gastric tube insertion, airway leakage pressure, and complications between the laryngeal mask airway (LMA) ProSeal (P-LMA) and I-gel (I-gel) groups.
Eighty patients with age range 18-65 years who underwent elective surgery were included in the study. The study took place in the operation rooms of Haydarpaşa Numune Hospital, Istanbul, Turkey from November 2013 to April 2014. Patients were equally randomized into 2 groups; the I-gel group, and the P-LMA group. In both groups, the same specialist inserted the supraglottic airway devices. The insertion time of the devices, difficulty during insertion, difficulty during gastric tube insertion, coverage of airway pressure, and complications were recorded.
The mean insertion time in the I-gel group was significantly lower than that of the P-LMA group (I-gel: 8±3; P-LMA: 13±5 s). The insertion success rate was higher in the I-gel group (100%, first attempt) than in the P-LMA group (82.5%, first attempt). The gastric tube placement success rate was higher in the I-gel group (92.5%, first attempt) than in the P-LMA group (72.5%, first attempt). The airway leakage pressures were similar.
Insertion was easier, insertion time was lower, and nasogastric tube insertion success was higher with the I-gel application, and is, therefore, the preferred LMA.
ProSeal Laryngeal Mask Airway (PLMA) is extensively being used in pediatric anesthesia.
To evaluate the efficacy of PLMA as compared to Classic Laryngeal Mask Airway (CLMA) for airway maintenance in pediatric patients.
Settings and Design:
A prospective, randomized, Single-blinded study was conducted in a tertiary care teaching hospital.
Materials and Methods:
Sixty ASA I and II children were included. Patients were randomized to either size 2 PLMA or size 2 CLMA groups. Parameters noted were time for insertion, number of attempts, airway sealing pressure, blood pressures (systolic, diastolic, and mean), pulse rate, end-tidal carbon dioxide (EtCO2), peripheral oxygen saturation (SpO2), and postoperative change in abdominal circumference, and airway trauma.
Statistical analysis used:
Parametric data were analyzed with the unpaired t-test and non-parametric data were analyzed with the chi-square (χ2) test. Unless otherwise stated, data are presented as mean (SD). Significance was taken as P < 0.05.
There was no statistical difference between the two groups for the success rates at the first attempt of insertion, airway sealing pressure, hemodynamic responses, SpO2, EtCO2 and postoperative changes in abdominal circumference. Patients in the PLMA group had longer time of insertion and higher incidence of airway trauma.
The PLMA and the CLMA were comparable for hemodynamic and ventilatory parameters and change in abdominal circumference; however, the time taken for insertion and airway trauma was more with PLMA.
Classic laryngeal mask airway; pediatric patients; ProSeal laryngeal mask airway
The aim of this study was to compare size 2 Laryngeal Mask Airway ProSeal and size 2 Laryngeal Mask Airway Supreme in spontaneously breathing children undergoing lower abdominal elective surgery of <1 hour duration.
Randomized clinical trial.
Material and Methods:
Sixty children aged 1–7 years, weighing 10–20 kg, ASA I physical status were randomly allocated to the Laryngeal Mask Airway ProSeal and Laryngeal Mask Airway Supreme.
There were no differences in demographic variables, ease of gastric tube placement, ease of insertion and ventilation, number of insertion attempts, hemodynamic changes on insertion, postoperative complications and bloodstaining between the groups. Gastric insufflation was detected and gastric tube was placed in all patients except one in LMA Supreme. Postoperative cuff volumes were comparable with the preoperative values in group itself. Oropharyngeal leak pressures were higher in Laryngeal Mask Airway ProSeal (24.6±5.5 vs 21.3±4.2, respectively; p<0.01).
As a result Laryngeal Mask Airway ProSeal and Laryngeal Mask Airway Supreme can safely be used in spontaneously breathing pediatric population undergoing lower abdominal elective surgery.
Laryngeal mask; proseal; supreme; children; oropharyngeal leak pressure
This randomized controlled study evaluated the success rate of insertion and the associated oropharyngeal morbidity for sizes 1.5,2 and 2.5 of ProSeal™ laryngeal mask airway (PLMA) using an alternative digital technique (D) with conventional technique using the introducer tool (IT) technique.
After approval from the hospital ethics committee, 250 healthy children, 6-months to 10 years of age, undergoing elective sub-umbilical surgeries, were included and randomly allocated to D and IT groups for PLMA insertion. The standard anaesthesia protocol was followed. The primary outcomes were success rate of insertion at first attempt and blood on device on removal and the secondary outcomes were oropharyngeal leak pressure and gastric tube placement.
The success rate of PLMA insertion at first attempt for sizes 1.5 and 2 did not differ between the two groups. However, for size 2.5, it was significantly lower than that for the other two sizes in both groups. The incidence of blood on device was higher with the 2.5 airway in both groups, reaching statistical significance only in group D. Other parameters did not differ between the two groups.
We conclude that size 2.5 PLMA is associated with a lower success rate of insertion and a higher incidence of blood on device using both techniques. Insertion of PLMA sizes 1.5 and 2 by an alternative digital technique is comparable to the IT technique.
Size-2.5 ProSeal™ LMA; success rate; pediatric
The ProSeal laryngeal mask airway (PLMA) is a unique laryngeal mask with a modified cuff to improve seal and a channel to facilitate gastric tube placement. This is a better device in difficult airway situations compared to classic laryngeal mask airway. This prompted us to study the ease of insertion and positioning of PLMA in patients with simulated restricted neck mobility while using gum elastic bougie (GEB) group or introducer tool (group IT) to aid insertion.
Sixty ASA I or II patients, aged between 18 years and 60 years, undergoing minor non-head and neck surgeries in the supine position were studied. A rigid neck collar was used to simulate restricted neck mobility in all patients. After anaesthetising the patients with a standard protocol, the PLMA was inserted using either of the technique using the tongue depressor to open the mouth. The ease of insertion, positioning, haemodynamic responses to insertion and other complications related to the procedure were noted.
Regarding demographic variables, both groups were similar. The mean time taken for insertion of PLMA in group GEB was 67.80 s as compared to 46.79 s in group IT (P<0.05). Patients of group GEB had better positioning assessed by an intubating fiberscope with less end tidal carbon-di-oxide (ETCO2) values. Systolic and diastolic blood pressures were similar. The incidence of sore throat, dysphagia, and dysphonia were higher in IT group in the 12 h, but similar in 24 h.
Guided insertion technique with GEB took a longer time, but had a better positioning and lower ETCO2 values when compared to IT technique.
Difficult airway; gum elastic bougie; ProSeal laryngeal mask; simulation
To assess the influence of proseal laryngeal mask airway (PLMA) insertion on intraocular pressure (IOP).
We compared the effects of PLMA insertion and laryngoscopic intubation on IOP and hemodynamic response in pediatric patients.
Previous studies have shown that there is no hemodynamic response to PLMA insertion similar to classic LMA insertion, but there is no published report about the influence of PLMA insertion on IOP. Conventional laryngoscopic tracheal intubation evokes a rise in IOP and cardiovascular response and has been traditionally used to secure the airway in pediatric patients undergoing ophthalmic surgery.
Materials and Methods:
59 patients, less than 14 years of age, scheduled for elective ophthalmic surgery were randomly divided into two groups, group P, in which the patient's airway was secured with PLMA (using introducer tool technique), and group T, in which the airway was secured with laryngoscopy-guided endotracheal intubation. Heart rate, blood pressure, and IOP were measured just before insertion of the airway device and subsequently three times at intervals of 1 min after insertion of the airway device.
In group T, there was a significant rise in IOP as well as hemodynamic parameters recorded. In group P, there was no significant rise in hemodynamic parameters, but a significant rise in IOP was found though the rise was less than in group T.
We conclude that the PLMA use is associated with lesser cardiovascular response and rise in IOP as compared to tracheal intubation.
Endotracheal intubation; intraocular pressure; proseal laryngeal mask airway
The ProSeal™ laryngeal mask (PLMA) is increasingly being used as an airway device for laparoscopic surgery. Its silicone cuff allows diffusion of nitrous oxide, carbon dioxide and other gases with resultant rise in its intracuff pressure during anesthesia. The present study was designed to investigate the intracuff pressure changes during anesthesia with and without nitrous oxide in patients undergoing laparoscopic surgery lasting up to two hours.
Materials and Methods:
One hundred patients, American Society of Anesthesiologists physical status 2 and 3, undergoing general anesthesia with muscle paralysis, were randomized into two groups of 50 patients each to receive an anesthetic gas mixture containing either oxygen and nitrous oxide (group N) or oxygen and air (group A). Following insertion of an appropriate size PLMA, its cuff was inflated with air to an intracuff pressure of 45 mm Hg. The cuff pressure was measured every 10 minutes for the entire course of anesthesia. The position of the device was also assessed fiberoptically and postoperative airway complications were recorded.
The maximum intracuff pressure recorded in group N was 103 ± 4.7 mm Hg vs. 45.5 ± 1.5 mm Hg in group A. The percentage rise in cuff pressure every 10 minutes was also highly significant (P < 0.001) being maximum in first 10 min in group N. The incidence of postoperative airway complications was comparable between the two groups.
The results of this study demonstrate that the intracuff pressure of the PLMA increases progressively over time when the breathing gas mixture contains nitrous oxide.
Anaesthetics; gases; nitrous oxide; equipment; laryngeal mask airway
The Guardian Laryngeal Mask Airway (G-LMA) is a new silicone-based single-use extraglottic device with the drainage port and a cuff pilot valve with pressure indicator. The aim of this study is to compare the clinical performance of this laryngeal mask airway with ProSeal laryngeal mask airway (P-LMA).
In this prospective randomized study, we included adult patients with ASA grading I and II scheduled for elective surgery requiring supine position under total intravenous anesthesia. The patients were randomly allocated to two groups, 40 in each. G-LMA and P-LMA were used in groups G and P respectively. The cuff of each device was air inflated to 60 cmH2O. The primary outcome was to compare the airway sealing pressure and the secondary outcome was to compare the efficacy and safety of these two devices with respect to insertion success, insertion time, ease of insertion, volume of air for cuff inflation to 60 cmH2O, intracuff pressure measurement, gastric tube insertion attempt, gastric tube insertion time, Fiberoptic laryngeal view, and postoperative pharyngolaryngeal morbidity.
The airway sealing pressure at 60cmH2O cuff pressure was significantly greater in G-LMA than P-LMA (p = 0.04).The first successful attempt of both groups were comparable (p = 1.000). Insertion time was significantly shorter in G-LMA than P-LMA (p < 0.0001). The first successful attempt for the gastric tube insertion in both groups was comparable (p = 0.431). Gastric tube insertion time was less in G-LMA than in P-LMA (p < 0.0001). The volume of air for cuff inflation to 60 cmH2O was more in G-LMA than in P-LMA (<0.0001). The intracuff pressure measurement at 30, 60, 90 and 120 minutes were comparable (p = 0.823, 0.182, 0.870, 0.658).We did not find differences in ease of insertion (p = 0.60); Fiber-optic positions of airway devices were comparable (p = 0.83). In addition, blood staining (p = 1.00), sore throat and dysphagia at 1, 2 and 24 hour (p = 1.00) were comparable in both groups.
The Guardian laryngeal mask airway was associated with high airway sealing pressure with a quicker insertion of the device as well as gastric tube.
Clinical Trial.gov Identifier: NCT02063516. Date: June 2013
Electronic supplementary material
The online version of this article (doi:10.1186/s12871-015-0039-3) contains supplementary material, which is available to authorized users.
Guardian laryngeal mask airway; ProSeal laryngeal mask airway; Ambu cuff pressure gauge
Sixty ASA grade I & II adult patients of either sex were randomly assigned into two groups. Group I (n=30) for I-gel and Group P (n=30) for LMA – ProSeal. We assessed the airway sealing pressure, ease of insertion, success rate of insertion, ease of gastric tube placement, airway trauma by post operative blood staining of the device, tongue, lip and dental trauma, hoarseness, regurgitation / aspiration and cost effectiveness. Although the airway sealing pressure was higher with Group P (29.6 cm H2O) than with Group I (25.27 cm H20) (p < 0.05), but the airway sealing pressure of Group I was very well within the normal limit to prevent aspiration. The ease of insertion was more with Group I (29/30) than with Group P (25/30) (p < 0.05). The success rate of first attempt of insertion and ease of gastric tube placement was more with Group I (p > 0.05). Blood staining of the device & tongue, lip and dental trauma was more with Group P (p >0.05). There was no evidence of bronchospasm, laryngospasm, regurgitation, aspiration or hoarseness in either group.
To conclude I-gel is a novel supraglottic device with an acceptable airway sealing pressure (25.27 cm H2O). It is easier to insert, requires less attempts of insertion, has easier gastric tube placement and is less traumatic as compared to LMA-ProSeal.
I-gel; LMA – ProSeal; Airway sealing pressure
The primary objective of this study was to compare the effect of ventilation using the ProSeal™ laryngeal mask airway (PLMA) with facemask and oropharyngeal airway (FM), prior to laryngoscopy, on arterial oxygenation in morbidly obese patients undergoing bariatric surgery.
Forty morbidly obese patients were randomly recruited to either PLMA or FM. After pre-oxygenation (FiO2 1.0) in the ramp position with continuous positive airway pressure of 10 cm H2O for 5 min, anaesthesia was induced. Following loss of jaw thrust oropharyngeal airway, the FM and PLMA were inserted. On achieving paralysis, volume control ventilation with PEEP (5 cm H2O) was initiated. The difficulty in mask ventilation (DMV) in FM, number of attempts at PLMA and laryngoscopy were graded (Cormack and Lehane) in all patients. Time from onset of laryngoscopy to endotracheal tube confirmation was recorded. Hypoxia was defined as mild (SpO2 ≤95%), moderate (SpO2 ≤90%) and severe (SpO2 ≤85%).
Significant rise in pO2 was observed within both groups (P=0.001), and this was significantly higher in the PLMA (P=0.0001) when compared between the groups. SpO2 ≥ 90% (P=0.018) was seen in 19/20 (95%) patients in PLMA and 13/20 (65%) in FM at confirmation of tracheal tube. A strong association was found between DMV and Cormack Lehane in the FM group and with number of attempts in the PLMA group. No adverse events were observed.
ProSeal™ laryngeal mask airway as conduit prior to laryngoscopy in morbidly obese patients seems effective in increasing oxygen reserves, and can be suggested as a routine airway management technique when managing the airway in the morbidly obese.
Bariatric; morbidly obese; oxygenation; ProSeal™
The use of suction catheter (SC) has been shown to improve success rate during ProSeal laryngeal mask airway (PLMA) insertion in expert users.
The aim of this study was to compare insertion of PLMA performed by untrained physicians using a SC or the digital technique (DT) in anaesthetised non-paralysed patients.
In this prospective randomised double-blind study, conducted in the operating setting, 254 patients (American Society of Anaesthesiologists I-II, aged 18-65 years), undergoing minor surgery were enrolled. Exclusion criteria were body mass index >35 kg/m2, laryngeal or oesophageal varices, risk of aspiration or difficult face mask ventilation either referred or suspected (Langeron's criteria ≥2) and modified Mallampati classification score >2. Participants were randomly allocated to one of the two groups in which PLMA was inserted using DT (DT-group) or SC (SC-group).
Chi-square test with Yates’ correction, Mann-Whitney U-test or Student's t-test were carried-out as appropriate.
The final insertion success rate was greater in SC-groupcompared with DT-group 90.1% (n = 109) versus 74.4% (n = 99) respectively (P = 0.002). Mean airway leak pressure was higher in SC-group compared to DT-group (23.7 ± 3.9 vs. 21.4 ± 3.2 respectively; (P = 0.001). There were no differences in insertion time, post-operative airway morbidity and complications.
The findings of this study suggest that SC-technique improves the success rate of PLMA insertion by untrained physicians.
Digital technique; ProSeal laryngeal mask airway; suction catheter technique; untrained physicians
Purpose. The size 1 I-gel, recommended for small infants and neonates weighing 2–5 kg, has recently been released. There are no prospective studies available that assess the insertion conditions, sealing pressures, or ventilation quality of it. This study was designed to compare the performance of recently released size 1 I-gel with size 1 ProSeal LMA. Methods. Fifty infants and neonates, ASA I-II were included in this prospective, randomized, and controlled study. Patients were divided into two groups for placing I-gel or ProSeal LMA. The primary outcome was airway leak pressure, and secondary outcomes included insertion time, insertion success and conditions, initial airway quality, fiberoptic view of the larynx, and complications. Results. There were no significant differences in terms of airway leak pressure between the I-gel (27.44 ± 5.67) and ProSeal LMA (23.52 ± 8.15) (P = 0.054). The insertion time for the I-gel was shorter (12.6 ± 2.19 s) than for the ProSeal LMA (24.2 ± 6.059 s) (P = 0.0001). Insertion success and conditions were similar in groups. We encountered few complications. Conclusion. Our study demonstrates that the size 1 I-gel provided an effective and satisfactory airway as the size 1 ProSeal LMA. It may be a good alternative supraglottic airway device for use in small infants and neonates. This trial is registered with: ClinicalTrials.gov NCT01704118.
Many tools have been developed to facilitate the insertion of the ProSeal laryngeal mask airway (LMA) insertion, which can be impeded by folding of its soft cuff. The aim of this study was to compare the efficiency of ProSeal LMA insertion guided by a soft, direct optical Foley Airway Stylet Tool (FAST) with the standard introducer tool (IT).
One hundred sixty patients undergoing general anesthesia using the ProSeal LMA as an airway management device were randomly allocated to either FAST-guided or IT-assisted groups. Following ProSeal LMA insertion, the glottic and esophageal openings were identified using a fiberoptic bronchoscope introduced through the airway and the drain tube. The primary outcomes were time taken to insert the ProSeal LMA and the success rate at the first attempt. Secondary end points included ease of insertion, hemodynamic response to insertion, and postoperative adverse events recorded in the recovery room and on the first postoperative morning.
One hundred forty patients were included in the final analysis: 66 in the FAST-guided group and 74 in the IT-assisted group. The success rate of FAST device-guided ProSeal LMA insertion (95.7%) was broadly comparable with IT-assisted insertion (98.7%). However, the time taken to insert the ProSeal LMA was significantly longer when the FAST technique was used (p <0.001). The incidence of correct alignment of the airway tube and the drain tube did not differ significantly between the groups. There were no significant differences in ease of insertion or hemodynamic responses to insertion, except that the incidence of postoperative sore throat was significantly higher in the FAST group on the first postoperative day (22.2% compared with 6.8% in the IT group; p =0.035).
Both FAST-guided and IT-assisted techniques achieved correct ProSeal LMA positioning, but the IT technique was significantly quicker and less likely to cause a sore throat.
ClinicalTrials.gov Identifier: NCT02048657
ProSeal laryngeal mask airway (LMA); Foley Airway Stylet Tool (FAST); Introducer tool (IT); Fiberoptic bronchoscope
In this study, the feasibility and performance of the combination of the Arndt endobronchial blocker and the laryngeal mask airway (LMA) ProSeal™ in airway establishment, ventilation, oxygenation and lung isolation was evaluated. Fifty-five patients undergoing general anesthesia for elective thoracic surgeries were randomly allocated to group Arndt (n=26) or group double-lumen tube (DLT; n=29). Data concerning post-operative airway morbidity, ease of insertion, hemodynamics, lung collapse, ventilators, oxygenation and ventilation were collected for analysis. Compared with group DLT, group Arndt showed a significantly attenuated hemodynamic response to intubation (blood pressure, 149±31 vs. 115±16 mmHg; heart rate, 86±15 vs. 68±15 bpm), less severe injuries to the bronchus (injury score, 1.4±0.2 vs. 0.4±0.1) and vocal cords (injury score, 1.3±0.2 vs. 0.6±0.1), and lower incidences of post-operative sore throat and hoarseness. Furthermore, the novel combination of the Arndt and the LMA ProSeal showed similar ease of airway establishment, comparable ventilation and oxygenation performance, and an analogous lung isolation effect to DLT. The novel combined use of the Arndt endobronchial blocker and the LMA ProSeal can serve as a promising alternative for thoracic procedures requiring one-lung ventilation. The less traumatic properties and equally ideal lung isolation are likely to promote its use in rapidly spreading minimally invasive thoracic surgeries.
one-lung ventilation; laryngeal mask airway; Arndt endobronchial blocker