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
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
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
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
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
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
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 sniffing position is recommended for conventional laryngeal mask airway (LMA) insertion. However, there has been a high success rate of LMA insertion with the head in the neutral position. The effect of a difficult airway on the ease of LMA insertion is not clear. In this study, we compared the ease of LMA ProSeal™ (PLMA) insertion and the fiberoptic scoring according to the head position and the presence of a difficult airway.
After obtaining informed consent from the subjects, we enrolled 144 adult patients (age range: 18-65) with an ASA physical status 1 or 2. After evaluation of the airway, all the patients were grouped into the EA (easy airway) group (n = 68) and the DA (difficult airway) group (n = 76). According to the head position, each group was divided into the EA-SE (extension) group (n = 35), the EA-SN (sniffing) group (n = 33), the DA-SE group (n = 39) and the DA-SN group (n = 37). The success rate and insertion time at the first attempt were evaluated. The position of the PLMA was fiberoptically scored from the mask aperture of the airway tube in the original head position. After the head position was changed to the sniffing and neutral positions in the SE and SN group, respectively, the position of PLMA was re-evaluated fiberoptically.
The success rate and insertion time at the first attempt and the fiberoptic score showed no significant difference among the groups. After head position was changed, there were no significant changes in the fiberopitc scores.
A difficult airway and the head position had no influence on the ease of PLMA insertion and the fiberopic score. Therefore, the head position can be selected according to the individual patient's situation.
Diffcult airway; Laryngeal mask airway; Neutral position; Sniffing position
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
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 (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 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 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™
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 Proseal™ laryngeal mask airway (PLMA™, Laryngeal Mask Company, UK) was designed to improve ventilatory characteristics and offer protection against regurgitation and gastric insufflation. The PLMA is a modified laryngeal mask airway with large ventral cuff, dorsal cuff and a drain tube. These modifications improve seal around glottis and enable better ventilatory characteristics. The drain tube prevents gastric distension and offers protection against aspiration. There were occasional problems, like failed insertion and inadequate ventilation, in placing PLMA™ using the classical digital technique. To overcome these problems, newer placement techniques like thumb insertion technique, introducer tool placement and gum elastic bougie (GEB)-aided placement were devised. We compared classical digital placement of PLMA™ with gum elastic bougie-aided technique in 60 anaesthetised adult patients (with 30 patients in each group) with respect to number of attempts to successful placement, effective airway time, airway trauma during insertion, postoperative airway morbidity and haemodynamic response to insertion. The number of attempts to successful placement, airway trauma during insertion and haemodynamic response to insertion were comparable among the two groups, while effective airway time and oropharyngeal leak pressure were significantly higher in bougie- guided insertion of PLMA. Postoperatively, sore throat was more frequent with digital technique while dysphagia was more frequent with bougie guided technique. Hence gum elastic bougie guided, laryngoscope aided insertion of PLMA is an excellent alternate to classical digital technique.
Anaesthesia; airway; equipment; laryngeal masks; technique; oropharyngeal seal pressure
We aimed to compare hemodynamic and endocrine alterations caused by stress response due to Proseal laryngeal mask airway and endotracheal tube usage in laparoscopic cholecystectomy.
Materials and Methods:
Sixty-three ASA I-II patients scheduled for elective laparoscopic cholecystectomy were included in the study. Patients were randomly allocated into two groups of endotracheal tube and Proseal laryngeal mask airway. Standard general anaesthesia was performed in both groups with the same drugs in induction and maintenance of anaesthesia. After anaesthesia induction and 20 minutes after CO2 insufflations, venous blood samples were obtained for measuring adrenalin, noradrenalin, dopamine and cortisol levels. Hemodynamic and respiratory parameters were recorded at the 1st, 5th, 15th, 30th and 45th minutes after the insertion of airway devices.
No statistically significant differences in age, body mass index, gender, ASA physical status, and operation time were found between the groups (p > 0.05). Changes in hemodynamic and respiratory parameters were not statistically significant when compared between and within groups (p > 0.05). Although no statistically significant differences were observed between and within groups when adrenalin, noradrenalin and dopamine values were compared, serum cortisol levels after CO2 insufflation in PLMA group were significantly lower than the ETT group (p = 0.024). When serum cortisol levels were compared within groups, cortisol levels 20 minutes after CO2 insufflation were significantly higher (46.1 (9.5-175.7) and 27.0 (8.3-119.4) in the ETT and PLMA groups, respectively) than cortisol levels after anaesthesia induction (11.3 (2.8-92.5) and 16.6 (4.4-45.4) in the ETT and PLMA groups, respectively) in both groups (p = 0.001).
PLMA usage is a suitable, effective and safe alternative to ETT in laparoscopic cholecystectomy patients with lower metabolic stress.
Endotracheal Tube; Proseal Laryngeal Mask Airway (PLMA); Hemodynamic Response; Metabolic Response
We performed a prospective, open-label, randomised controlled trial comparing the air-Q® against the LMA-ProSeal™ in adults undergoing general anaesthesia. One hundred subjects (American Society of Anesthesiologists physical status 1–3) presenting for elective, outpatient surgery were randomly assigned to 52 air-Q® and 48 ProSeal devices. The primary study endpoint was airway seal pressure. Oropharyngolaryngeal morbidity was assessed secondarily. Mean (SD) airway seal pressures for the air-Q® and ProSeal were 30 (7) cmH2O and 30 (6) cmH2O, respectively (p = 0.47). Postoperative sore throat was more common with the air-Q® (46% vs 38%, p = 0.03) as was pain on swallowing (30% vs 5%, p = 0.01). In conclusion, the air-Q® performs well as a primary airway during the maintenance of general anaesthesia with an airway seal pressure similar to that of the ProSeal, but with a higher incidence of postoperative oropharyngolaryngeal complaints.
Supraglottic devices have changed the face of the airway management. These devices have contributed in a big way in airway management especially, in the difficult airway scenario significantly decreasing the pharyngolaryngeal morbidity. There is a plethora of these devices, which has been well matched by their wider acceptance in clinical practice. ProSeal laryngeal mask airway (PLMA) is one such frequently used device employed for spontaneous as well as controlled ventilation. However, the use of PLMA at times maybe associated with certain problems. Some of the problems related with its use are unique while others are akin to the classic laryngeal mask airway (cLMA). However, expertise is needed for its safe and judicious use, correct placement, recognition and management of its various malpositions and complications. The present article describes the tests employed for proper confirmation of placement to assess the ventilatory and the drain tube functions of the mask, diagnosis of various malpositions and the management of these aspects. All these areas have been highlighted under the heading of troubleshooting PLMA. Many problems can be solved by proper patient and procedure selection, maintaining adequate depth of anaesthesia, diagnosis and management of malpositions. Proper fixation of the device and monitoring cuff pressure intraoperatively may bring down the incidence of airway morbidity.
Airway management; Equipment; ProSeal laryngeal mask airway; Classic laryngeal mask airway; Troubleshooting
Aims to compare the efficacy of Proseal laryngeal mask airway(PLMA) and endotracheal tube (ETT) in patients undergoing laparoscopic surgeries under general anaesthesia. This prospective randomised study was conducted on 60 adult patients, 30 each in two groups, of ASA I-II who were posted for laparoscopic procedures under general anaesthesia. After preoxygenation, anaesthesia was induced with propofol, fentanyl and vecuronium. PLMA or ETT was inserted and cuff inflated. Nasogastric tube (NGT) was passed in all patients. Anaesthesia was maintained with N2 O, O2, halothane and vecuronium. Ventilation was set at 8 ml/kg and respiratory rate of 12/min. The attempts and time taken for insertion of devices, haemodynamic changes, oxygenation, ventilation and intraoperative and postoperative laryngopharyngeal morbidity (LPM) were noted. There was no failed insertion of devices. Time taken for successful passage of NGT was 9.77 s (6-16 s) and 11.5 s (8-17 s) for groups P and E, respectively. There were no statistically significant differences in oxygen saturation (SpO2) or end-tidal carbon dioxide (EtCO2) between the two groups before or during peritoneal insufflation. Median (range) airway pressure at which oropharyngeal leak occurred during the leak test with PLMA was 35 (24-40) cm of H2O. There was no case of inadequate ventilation, regurgitation, or aspiration recorded. No significant difference in laryngopharyngeal morbidity was noted. A properly positionedPLMA proved to be a suitable and safe alternative to ETT for airway management in elective fasted, adult patients undergoing laparoscopic surgeries. It provided equally effective pulmonary ventilation despite high airway pressures without gastric distention, regurgitation, and aspiration.
Endotracheal tube; IPPV; laparoscopy; oropharyngeal seal pressure; Proseal LMA
Negative pressure pulmonary oedema (NPPO) is a life threatening condition, manifested due to upper airway obstruction in a spontaneously breathing patient. Upper airway obstruction caused by classic laryngeal mask airway (cLMA) and ProSeal laryngeal mask airway (PLMA) has been reported, and NPPO has also been reported following the use of cLMA. Search of literature did not confirm NPPO following the use of PLMA. We encountered a female patient of NPPO scheduled for incision and drainage of an abscess who had signs of airway obstruction following PLMA insertion. Multiple attempts were made to get patent airway without success. PLMA was replaced with endotracheal tube following which pink frothy secretion appeared in breathing circuit. Patient was managed successfully with ICU care.
Airway obstruction; negative pressure; negative pressure pulmonary oedema; ProSeal laryngeal mask airway
The laryngeal mask airway-ProSeal™ can be inserted digitally, by introducer tool, or by railroading it over a bougie placed first in the patient's oesophagus, which is highly successful, but as originally described, requires an assistant. An unassisted bougie-guided placement technique has also been described, but no data on its effectiveness have been reported.
We reviewed data collected during a randomized, controlled trial comparing the air-Q® Intubating Laryngeal Airway and LMA-Proseal™, in which all LMA-Proseal™ devices were inserted using the unassisted (one-operator), bougie-guided placement technique.
Forty-eight devices were placed. All devices were placed successfully. Successful placement was achieved in 47 (98%) patients on first attempt and in one (2%) patient on the third attempt. Mean (SD) time required for insertion establishing ventilation was 28 (11) s. Mean (SD) airway seal pressure was 30 (6) cmH2O. Gross blood was found on four (8%) devices upon removal, but no oropharyngeal injuries were noted on oral exam in the recovery unit prior to discharge. The most common complaints in recovery and 24 h post-operatively were sore throat [discharge: mild = 18/48 (38%); 24 h: mild = 9/38 (19%), moderate = 1/38 (3%)] and pain on swallowing [discharge: mild = 7/48 (15%); 24 h: mild = 2/38 (6%)].
Our data confirm that in experienced hands, bougie-guided placement of the LMA-Proseal™ without the aid of an assistant can be accomplished quickly and successfully without affecting the expected clinical performance of the device.
Bougie; insertion; LMA; Proseal
Supraglottic airway devices (SADs), such as ProSealTM laryngeal mask airway (PLMA), which produce high oropharyngeal seal pressure (OSP) and have the facility for gastric decompression have been used in laparoscopic procedures. i-gel is a new SAD which shares these features with the PLMA. This study was designed to compare the respiratory mechanics of these two devices during positive pressure ventilation in anaesthetised adult patients undergoing laparoscopic cholecystectomy.
Patients & Methods:
The study included 60 ASA I-II adult patients scheduled for laparoscopic cholecystectomy. The patients were randomized to two groups of 30 each, with either PLMA or i-gel as their airway device. Anaesthesia and premedication were standardized for both the groups. In addition to routine monitoring, neuromuscular monitoring with TOF ratio, OSP and respiratory mechanics monitoring (dynamic compliance, resistance, work of breathing, measured minute ventilation and peak airway pressures) were employed. Fibreoptic evaluation of positioning of the devices and adverse events related to them were also compared.
The OSP (cm H2O) were higher for PLMA (38.9 vs. 35.6, P=0.007). The respiratory mechanics parameters using the two devices were comparable apart from the dynamic compliance, which was significantly higher with i-gel (P < 0.05). Malrotation was higher with i-gel than with PLMA (15 vs. 5, P = 0.006).
The PLMA formed a better seal while the dynamic compliance was higher with the i-gel. Both devices provided optimal ventilation and oxygenation and the adverse events were also comparable.
ProSealTM LMA; I-gel; Equipment; Masks anaesthesia; Respiratory mechanics; Laparoscopy; Ventilation
Supraglottic airway devices play an important role in ophthalmic surgery. The flexible laryngeal mask airway (LMA™) is generally the preferred airway device. However, there are no studies comparing it with the Cobra perilaryngeal airway (CobraPLA™) in pediatric ophthalmic procedures.
To analyze the intraoperative device stability and ability to maintain normocarbia of CobraPLA™ and compare it to that with flexible LMA™.
Materials and Methods:
Ninety children of American Society for Anesthesiologists physical status 1 and 2, aged 3–15 years scheduled for elective ophthalmic surgeries were randomly assigned to either the CobraPLA™ or the flexible LMA™ group. After placement of each airway device, oropharyngeal leak pressure (OLP) was noted. Adequate seal of the devices was confirmed at an inspired pressure of 15 cm H2O and pressure-controlled ventilation was initiated. Device displacement was diagnosed if there was a change in capnograph waveform, audible or palpable gas leak, change in expired tidal volume to <8 ml/kg, end-tidal carbon-dioxide persistently >6 kPa, or need to increase inspired pressure to >18 cm H2O to maintain normocarbia.
Demographic data, duration, and type of surgery in both the groups were similar. A higher incidence of intraoperative device displacement was noted with the CobraPLA™ in comparison to flexible LMA™ (P < 0.001). Incidence of displacement was higher in strabismus surgery (7/12). Insertion characteristics and ventilation parameters were comparable. The OLP was significantly higher in CobraPLA™ group (28 ± 6.8 cm H2O) compared to the flexible LMA™ group (19.9 ± 4.5 cm H2O) (P < 0.001). Higher surgeon dissatisfaction (65.9%) was seen in the CobraPLA™ group.
The high incidence of device displacement and surgeon dissatisfaction make CobraPLA™ a less favorable option than flexible LMA™ in ophthalmic surgery.
Airway complication; CobraPLA™; flexible laryngeal mask airway; pediatric ophthalmic surgery
The Laryngeal Mask Airway (LMA) is a frequently-used efficient airway device, yet it sometimes seals poorly, thus reducing the efficacy of positive-pressure ventilation. The Perilaryngeal Airway (CobraPLA) is a novel airway device with a larger pharyngeal cuff (when inflated). We tested the hypothesis that the CobraPLA was superior to LMA with regard to insertion time and airway sealing pressure and comparable to LMA in airway adequacy and recovery characteristics. After midazolam and fentanyl, 81 ASA I-II outpatients having elective surgery were randomized to receive an LMA or CobraPLA. Anesthesia was induced with propofol (2.5 mg/kg, IV), and the airway inserted. We measured 1) insertion time; 2) adequacy of the airway (no leak at 15-cm-H2O peak pressure or tidal volume of 5 ml/kg); 3) airway sealing pressure; 4) number of repositioning attempts; and 5) sealing quality (no leak at tidal volume of 8 ml/kg). At the end of surgery, gastric insufflation, postoperative sore throat, dysphonia, and dysphagia were evaluated. Data were compared with unpaired t-tests, chi-square tests, or Fisher’s Exact tests; P<0.05 was significant. Patient characteristics, insertion times, airway adequacy, number of repositioning attempts, and recovery were similar in each group. Airway sealing pressure was significantly greater with CobraPLA (23±6 cm H2O) than LMA (18±5 cm H2O, P<0.001). The CobraPLA has insertion characteristics similar to LMA, but better airway sealing capabilities.
Airway: Sealing. Cuff Pressure. Insertion. Leak. Pharynx; Equipment: Laryngeal mask airway. Perilaryngeal airway; Ventilation: Controlled. Spontaneous; Anesthesia
The i-gel™, LMA-Supreme (LMA-S) and Laryngeal Tube Suction-D (LTS-D) are single-use supraglottic airway devices with an inbuilt drainage channel. We compared them with regard to their position in situ as well as to clinical performance data during elective surgery.
Prospective, randomized, comparative study of three groups of 40 elective surgical patients each. Speed of insertion and success rates, leak pressures (LP) at different cuff pressures, dynamic airway compliance, and signs of postoperative airway morbidity were recorded. Fibreoptic evaluation was used to determine the devices’ position in situ.
Leak pressures were similar (i-gel™ 25.9, LMA-S 27.1, LTS-D 24.0 cmH2O; the latter two at 60 cmH2O cuff pressure) as were insertion times (i-gel™ 10, LMA-S 11, LTS-D 14 sec). LP of the LMA-S was higher than that of the LTS-D at lower cuff pressures (p <0.05). Insertion success rates differed significantly: i-gel™ 95%, LMA-S 95%, LTS-D 70% (p <0.05). The fibreoptically assessed position was more frequently suboptimal with the LTS-D but this was not associated with impaired ventilation. Dynamic airway compliance was highest with the i-gel™ and lowest with the LTS-D (p <0.05). Airway morbidity was more pronounced with the LTS-D (p <0.01).
All devices were suitable for ventilating the patients’ lungs during elective surgery.
German Clinical Trial Register DRKS00000760
Laryngeal mask airway; Leak pressure; Laryngeal Tube