Evaluation of the LMA Supreme™in 100 non-paralysed patients

Head Rotation Reduces Oropharyngeal Leak Pressure of the i-gel and LMA® Supreme™ in Paralyzed, Anesthetized Patients: A Randomized Trial

BACKGROUND

Second-generation supraglottic airway (SGA) devices are useful for airway management during positive pressure ventilation in general anesthesia and emergency medicine. In some clinical settings, such as the anesthetic management of awake craniotomy, SGAs are used in the head-rotated position, which is required for exposure of the surgical field, although this position sometimes worsens the efficiency of mechanical ventilation with SGAs. In this study, we investigated and compared the influence of head rotation on oropharyngeal leak pressures (OPLP) of the i-gel and LMA® Supreme™, which are second-generation SGA devices.

METHODS

Patients who underwent elective surgery under general anesthesia were enrolled in this study and randomly divided into i-gel or LMA Supreme groups. After induction of anesthesia with muscle relaxation, the i-gel or LMA Supreme was inserted according to computerized randomization. The primary outcome was the OPLP at 0°, 30°, and 60° head rotation. The secondary outcomes were the maximum airway pressure and expiratory tidal volume when patients were mechanically ventilated using a volume-controlled ventilation mode with a tidal volume of 10 mL/kg (ideal body weight), ventilation score, and fiber-optic views of vocal cords.

RESULTS

Thirty-four and 36 participants were included in the i-gel and LMA Supreme groups, respectively. The OPLPs of the i-gel and LMA Supreme significantly decreased as the head rotation angle increased (mean difference [95% confidence interval], P value: i-gel; 0° vs 30°: 3.5 [2.2-4.8], P < .001; 30° vs 60°: 2.0 [0.6-3.5], P = .002; 0° vs 60°: 5.5 [3.3-7.8], P < .001, LMA Supreme; 0° vs 30°: 4.1 [2.6-5.5], P < .001; 30° vs 60°: 2.4 [1.1-3.7], P < .001; 0° vs 60°: 6.5 [5.1-8.0], P < .001). There were statistically significant differences in expiratory tidal volume and ventilation score between 0° and 60° in the i-gel group and in ventilation score between 30° and 60° in the LMA Supreme group. There was no statistically significant difference between the 2 devices in all outcome measures. The incidences of adverse events, such as hoarseness or sore throat, were not significantly different between i-gel and LMA Supreme.

CONCLUSIONS

Head rotation to 30° and 60° reduces OPLP with both i-gel and LMA Supreme. There is no difference in OPLP between i-gel and LMA Supreme in the 3 head rotation positions.

Comparison of airway management without neuromuscular blockers in laparoscopic gynecological surgery

New generation supraglottic airway devices are suitable for airway management in many laparoscopic surgeries. In this study, we evaluated and compared the ventilation parameters of the laryngeal mask airway-supreme (LM-S) and endotracheal tube (ETT) when a neuromuscular blocker (NMB) agent was not used during laparoscopic gynecological surgery. The second outcome was based on the evaluation of the surgical view because it may affect the surgical procedure.This was a randomized study that enrolled 100 patients between 18 and 65 years old with an ASA I-II classification. Patients were divided into 2 groups: Group ETT and Group LM-S. Standard anesthesia and ventilation protocols were administered to patients in each group. Ventilation parameters [airway peak pressure (Ppeak), mean airway pressure (Pmean), total volume, and oropharyngeal leak pressure] were recorded before, after, and during peritoneal insufflation and before desufflation, as well as after the removal of the airway device. Perioperative surgical view quality and the adequacy of the pneumoperitoneum were also recorded.The data of 100 patients were included in the statistical analysis. The Ppeak values in Group ETT were significantly higher in the second minute after airway device insertion. The Ppeak and Pmean values in Group ETT were significantly higher before desufflation and after removal of the airway device. No significant differences were found between the groups in terms of adequacy of the pneumoperitoneum or quality of the surgical view.The results of this study showed that gynecological laparoscopies can be performed without using a NMB. Satisfactory conditions for ventilation and surgery can be achieved while sparing the use of muscle relaxants in both groups despite the Trendelenburg position and the pneumoperitoneum of the patients, which are typical for laparoscopic gynecological surgery. The results are of clinical significance because they show that the use of a muscle relaxant is unnecessary when supraglottic airways are used for these surgical procedures.

Risk factors for difficult Laryngeal Mask Airway LMA-Supreme™ (LMAS) placement in adults: a multicentric prospective observational study in an Italian population

BACKGROUND

Supraglottic airway devices (SADs) are precious tools for airway management in both routine and rescue situations; few studies have analyzed the risk factors for their difficult insertion.

METHODS

The aim of this study was to identify the risk factors for difficult insertion for a specific SAD, the Laryngeal Mask Airway LMA-Supreme™ (LMAS). This was a prospective multicentric observational study on a cohort of Italian adult patients receiving general anesthesia for elective surgery. The possible causes of difficulty in LMAS placement (difficulty in insertion or unsatisfactory ventilation) were identified based on literature and on the opinion of international airway management experts. A dedicated datasheet was prepared to collect patients' data, including anthropometric-parameters and parameters for the prediction of difficult airway management, as well as technical choices for the use of LMAS. Data were analyzed to discover the risk factors for difficult LMAS placement and the association between each risk factor and the proportion of incorrect positioning was evaluated through the relative risk and its confidence interval.

RESULTS

Four hundred thirty-two patients were enrolled; seventy required two or more attempts to insert the LMAS; nine required a change of strategy. At multivariate analysis, the following factors were significantly associated with difficult LMAS placement: Mallampati III-IV with either phonation or not; inter-incisor distance < 3 cm; reduced neck mobility; no administration of neuromuscular blocking agents (NMBAs).

CONCLUSIONS

The alignment of the laryngeal and pharyngeal axes seems to facilitate the procedure, together with NMBA administration; on the contrary, Mallampati grade III-IV are associated with difficult LMAS placement.

Comparison of LM-Supreme™ and endotracheal tube in patients undergoing gynecological laparoscopic surgery

While laryngeal mask is widely used for laparoscopic interventions in some countries, concerns exist regarding pulmonary aspiration and inadequate ventilation. We compared the LM-Supreme™ (LM-S) with the endotracheal tube (ETT) for laparoscopic gynecological interventions in terms of ventilation parameters and gastric distention. This prospective randomized and double-blind study. The patients were divided into two groups: ETT (n = 50) and LM-S group (n = 50). All patients in the LM-S and ETT groups recieved total intravenous general anaesthesia and standard ventilation protocols. Ventilation parameters (airway peak pressure, mean airway pressure, end-tidal carbon dioxide, total volume, oropharyngeal leak pressure) and perioperative laryngopharyngeal morbidity were recorded before peritoneal insufflation, during and after the peroperative period. The mean airway pressure values in the ETT group 2 min after airway device insertion were significantly higher. The gastric distension after the laparoscope entered the abdomen in the LM-S group was found to be significantly lower. In the first hour postoperative sore throat, disphonia and dysphagia were statistically significantly higher in the ETT group. In our study we concluded that LM-S provides reliable endotracheal intubation in ASA I & II patients undergoing laparoscopic gynecological surgery under positive pressure ventilation.ClinicalTrials.gov ID NCT02127632.

Supreme™ laryngeal mask airway insertion requires a lower concentration of sevoflurane than ProSeal™ laryngeal mask airway insertion during target-controlled remifentanil infusion: a prospective randomised controlled study

Background

ProSeal (PLMA) and Supreme (SLMA) laryngeal mask airways are effective ventilator devices with distinctive designs that may require different anaesthetics for insertion. Sevoflurane induction provides acceptable conditions for laryngeal mask insertion, and remifentanil significantly decreases the minimum alveolar concentration of sevoflurane required for that insertion. The study aimed to evaluate the optimal end-tidal (ET) sevoflurane concentration for successful insertion of PLMA versus SLMA in patients receiving a remifentanil infusion without a neuromuscular blocking agent.

Methods

Altogether, 45 patients ASA (American Society Anaesthesiologists) physical status I–II, aged 18–60 years were scheduled for elective ambulatory surgery. Exclusion criteria were a difficult airway, recent respiratory infection, reactive airway, obstructive sleep apnoea syndrome, gastric aspiration’s risk factors, pregnancy, and lactation. Patients were randomly allocated to receive the SLMA or the PLMA. Sevoflurane induction with co-administration of remifentanil was performed at an effect-site concentration of 4 ng mL^− 1. ET₅₀ was calculated with a modified Dixon’s up-and-down method (starting at 2.5% in steps of 0.5%). Predetermined sevoflurane concentration was kept constant during the 10 min before LMA insertion. Patient’s response to LMA insertion was classified as “movement” or “no movement”. Sevoflurane ET₅₀ was determined as the midpoint concentration of all the independent pairs that manifested crossover from “movement” to “no movement”.

Results

The ET₅₀ sevoflurane concentration co-administered with remifentanil required for PLMA insertion was 1.20 ± 0.41% (95% confidence interval 0.76 to 1.63%). For SLMA insertion, it was 0.55 ± 0.38% (95% confidence interval 0.14 to 0.95%) (p = 0.019).

Conclusions

The end-tidal sevoflurane concentration with co-administered remifentanil required to allow insertion of the SLMA was 54% lower than that needed for inserting the PLMA.

Trial registration

Clinicaltrials.gov identifier: NCT03003377. Retrospectively registered. Date of registration: December 28, 2016.

A comparison between the Supreme laryngeal mask airway and the laryngeal tube suction during spontaneous ventilation: A randomized prospective study

BACKGROUND AND AIMS

The Supreme laryngeal mask airway (SLMA) and the laryngeal tube suction-disposable (LTS-D), both second-generation supraglottic airway devices, have a record of efficiency when used for airway management in mechanically ventilated patients, during general anesthesia. There is no published data comparing these two devices in patients breathing spontaneously during general anesthesia.

MATERIAL AND METHODS

Eighty patients with normal airways undergoing elective general anesthesia with spontaneous ventilation were randomized to airway management with a SLMA or LTS-D. Efficacy and adequacy of oxygenation and ventilation were compared.

RESULTS

No cases of desaturation of oxygen saturation (SpO2) values of less than 95% occurred with either device. The mean difference for SpO2 between the two devices (0.7%) has no clinical significance. Slight hypercapnia was noted with both devices to acceptable values during spontaneous ventilation.

CONCLUSIONS

Both SLMA and LTS-D are suitable and effective for airway management in patients breathing spontaneously during general anesthesia for minor surgery of short duration.

Direct and indirect low skill fibre-optic intubation: A randomised crossover manikin study of six supraglottic airway devices

Background and Aims:

Fibre-optic intubation (FOI) through supraglottic airway devices (SADs) is useful in the management of the difficult airway. We compared two methods of FOI through seven SADs in a randomised crossover manikin study to assess each device's performance and discuss implications on SAD selection.

Methods:

Thirty anaesthetsiologists, 15 seniors and 15 juniors, each performed low skill FOI (LSFOI) with seven SADs using both 'direct' and 'indirect' methods. The order of method and device used were randomised. The primary end point was success rate of intubation; secondary end points were time taken for intubation, incidence of difficulties with direct and indirect LSFOI and operator device preference. Statistical analysis was with univariable analysis and comparison of proportions.

Results:

Data from six devices were analysed due to a protocol breach with one SAD. There was no difference in intubation success rate across all SADs and intubation methods. Intubation time was significantly shorter in AmbuAuragain than other SADs and shorter with the direct method of LSFOI than the indirect method (mean difference of 6.9 s, P = 0.027). Ambu Auragain had the least SAD and bronchoscope-related difficulties. Seniors had significantly shorter mean intubation times than juniors by 11.6 s (P = 0.0392). The most preferred SAD for both methods was AmbuAuragain.

Conclusion:

Low skill FOI consistently achieves a high intubation success rate regardless of experience, choice of method, or SAD used. SAD design features may significantly affect the performance of low skill FOI.

Comparison of oropharyngeal leak pressure of air-Q™, i-gel™, and laryngeal mask airway supreme™ in adult patients during general anesthesia: A randomized controlled trial

Study Objective:

Various randomized controlled trials and a meta-analysis have compared i-gel™ and laryngeal mask airway Supreme™ (LMA-S™) in adult patients and found that both the devices provided equivalent oropharyngeal leak pressure (OLP). However, no randomized controlled trial has compared air-Q™ with i-gel™ and LMA-S™ in adult patient. Hence, we designed this study to compare air-Q™ with LMA-S™ and i-gel™ in adult patients.

Materials and Methods:

A total of 75 adult patients of the American Society of Anesthesiologists physical status I/II of both sexes, between 18 and 60 years, were included in this prospective randomized controlled trial conducted in a tertiary care center. Randomization of patients was done in three equal groups according to the insertion of supraglottic airway device by a computer-generated random number sequence: group air-Q™ (n = 25), group i-gel™ (n = 25), and group LMA-S™ (n = 25). Primary outcome of this study was OLP. We also recorded time for successful placement of device, ease of device insertion, number of attempts to insert device, and ease of gastric tube insertion along with postoperative complications.

Results:

The mean ± standard deviation OLP of air-Q™, i-gel™, and LMA-S™ was 26.13 ± 4.957 cm, 23.75 ± 5.439 cm, and 24.80 ± 4.78 cm H₂O (P = 0.279). The first insertion success rate for air-Q™, i-gel™, and LMA-S™ was 80%, 76%, and 92%, respectively (P = 0.353). The insertion time of air-Q™, i-gel™, and LMA-S™ was 20.6 ± 4.4, 14.8 ± 5.4, and 15.2 ± 4.7 s, respectively (P = 0.000). Time taken for air-Q™ insertion was significantly higher than time taken for i-gel™ (mean difference 5.8 s, P < 0.0001) and LMA-S™ (mean difference 5.4 s, P = 0.0001) insertion. Postoperative complications were similar with all three devices.

Conclusions:

We concluded that air-Q™, i-gel™, and LMA-S™ were equally efficacious in terms of routine airway management in adult patients with normal airway anatomy.

A comparison of i-gel™ and Laryngeal Mask Airway Supreme™ during general anesthesia in infants

Background

The i-gel™ (i-gel) and Laryngeal Mask Airway Supreme™ (LMA Supreme) have been safely used in children. We compared the airway performance of the i-gel and LMA Supreme in infants undergoing general anesthesia.

Methods

Sixty infants with American Society of Anesthesiologists physical status I or II were randomly assigned to place either the i-gel or the LMA Supreme. The size 1 or 1.5 of each airway was selected by the weight of infants. The primary outcome variable was oropharyngeal leak pressure (OLP). We also assessed insertion success rate, insertion time, fiberoptic view of the larynx, airway quality, airway manipulations, and perioperative complications.

Results

Demographic data did not differ between the two groups. Insertion success rate was similar in both groups. OLP for the i-gel (26.0 ± 3.8 cmH₂O) was higher than for the LMA Supreme (23.7 ± 3.2 cmH₂O) (P = 0.016). Insertion time for the i-gel (16.4 ± 2.8 s) was shorter than for the LMA Supreme (18.5 ± 2.7 s) (P = 0.002). There were no differences in fiberoptic view of the larynx, airway quality, airway manipulations, and complications between the two groups.

Conclusions

This study demonstrated that the i-gel and LMA Supreme provided a similar performance of airway in infants. Compared with the LMA Supreme, the i-gel provided shorter insertion time and higher OLP in infants.

A preliminary assessment of the LMA protector™ in non-paralysed patients

BACKGROUND

The LMA Protector™ is the latest CE marked single use supraglottic airway device. This airway device provides access and functional separation of the respiratory and digestive tracts. There are two ports (male, female ports) to provide suction in the laryngeal region and insertion of the gastric tube. The aim of our study is to assess the ease of use, airway quality, device positioning, airway leak and complications associated with initial clinical experience in LMA Protector™ usage.

METHODS

This is an initial investigation of LMA Protector™ airway device. We conducted a preliminary assessment in the anaesthetised women who underwent minor gynaecological procedures with spontaneous ventilation in order to evaluate the performance of the airway device.

RESULTS

Insertion was successful on first and second attempts in 23 (88.5%) and 3 (11.5%) respectively. Median [IQR (range)] insertion time was 19 [17-21(14-58)] seconds. Airway leak pressure was 25.5 [23-29(21-30] cmH₂O. On fibreoptic examination via the device, vocal cords were visible in all 26 patients. There were no alternative airway use or airway manipulations required during maintenance of anaesthesia. Six patients had sore throat 24 h after procedures and there was no dysphagia or hoarseness.

CONCLUSION

This pilot study of the LMA protector shows that the device is easily inserted with fast insertion time, providing a reliable and adequate airway seal.

TRIAL REGISTRATION

Clinicaltrials.gov Registration NCT02531256 . Retrospectively registered on August 21, 2015.

A randomized prospective controlled trial comparing the laryngeal tube suction disposable and the supreme laryngeal mask airway: the influence of head and neck position on oropharyngeal seal pressure

BACKGROUND

The Laryngeal Tube Suction Disposable (LTS-D) and the Supreme Laryngeal Mask Airway (SLMA) are second generation supraglottic airway devices (SADs) with an added channel to allow gastric drainage. We studied the efficacy of these devices when using pressure controlled mechanical ventilation during general anesthesia for short and medium duration surgical procedures and compared the oropharyngeal seal pressure in different head and-neck positions.

METHODS

Eighty patients in each group had either LTS-D or SLMA for airway management. The patients were recruited in two different institutions. Primary outcome variables were the oropharyngeal seal pressures in neutral, flexion, extension, right and left head-neck position. Secondary outcome variables were time to achieve an effective airway, ease of insertion, number of attempts, maneuvers necessary during insertion, ventilatory parameters, success of gastric tube insertion and incidence of complications.

RESULTS

The oropharyngeal seal pressure achieved with the LTS-D was higher than the SLMA in, (extension (p=0.0150) and right position (p=0.0268 at 60 cm H2O intracuff pressures and nearly significant in neutral position (p = 0.0571). The oropharyngeal seal pressure was significantly higher with the LTS-D during neck extension as compared to SLMA (p= 0.015). Similar oropharyngeal seal pressures were detected in all other positions with each device. The secondary outcomes were comparable between both groups. Patients ventilated with LTS-D had higher incidence of sore throat (p = 0.527). No major complications occurred.

CONCLUSIONS

Better oropharyngeal seal pressure was achieved with the LTS-D in head-neck right and extension positions , although it did not appear to have significance in alteration of management using pressure control mechanical ventilation in neutral position. The fiberoptic view was better with the SLMA. The post-operative sore throat incidence was higher in the LTS-D.

TRIAL REGISTRATION

ClinicalTrials.gov ID: NCT02856672 , Unique Protocol ID:BnaiZionMC-16-LG-001, Registered: August 2016.

An Evaluation of Thyromental Distance-based Method or Weight-based Method in Determining the Size of the Laryngeal Mask Airway Supreme: A Randomized Controlled Study

The successful placement of Laryngeal Mask Airway (LMA) Supreme in adults largely depends on right selection of its size. Most anesthesiologists determine the size of LMA according to patients' body weight, which does not always work well. An alternative method should be established to guarantee higher efficacy of ventilation through LMA Supreme placement. This controlled study was designed to compare the efficacy of LMA Supreme placement, when the size of it is determined by body weight or by thyromental distance. Eighty healthy individuals with American Society of Anesthesiologists physical status 1 to 2 scheduled for elective ambulatory surgery were randomly allocated into 2 groups: thyromental distance-based group (n = 40) and weight-based group (n = 40). Efficacy of controlled ventilation through LMA, easy of device placement, and pharyngeal sealing were evaluated between the groups. The tidal volume under 10 cm H2O pressure-controlled ventilation in thyromental distance-based group was significantly higher than that in weight-based group (523.9 ± 135.4 vs 477.1 ± 185.6; P = 0.031). The number of patients who achieved "excellent" tidal volume (>8 mL/kg) were significantly more in the thyromental distance-based group (24/40 vs 13/40; P = 0.019). Among overweight patients (body mass index >23), those who achieved "excellent" tidal volume (>8 mL/kg) under 10 cm H2O pressure-controlled ventilation were also more in thyromental distanced-based group than in weight-based group (11/24 vs 2/24; P = 0.031). The time taken for successful insertion was shorter with the thyromental distance-based group compared with the weight-based group (54.6 ± 33.6 vs 87.8 ± 98.9; P = 0.021). Oropharyngeal leak pressure was pretty close between the 2 groups (26.4 ± 5.1 vs 25.0 ± 5.7 cm H2O; P = 0.180). In terms of guaranteeing better positive pressure ventilation, facilitating device placement, and reliable pharyngeal sealing, thyromental distance-based method can be a better option compared with the weight-based method for LMA Supreme size selection.

Supreme Laryngeal Mask Airway versus Face Mask during Neonatal Resuscitation: A Randomized Controlled Trial

OBJECTIVE

To assess the effectiveness of supreme laryngeal mask airway (SLMA) over face mask ventilation for preventing need for endotracheal intubation at birth.

STUDY DESIGN

We report a prospective, randomized, parallel 1:1, unblinded, controlled trial. After a short-term educational intervention on SLMA use, infants ≥34-week gestation and/or expected birth weight ≥1500 g requiring positive pressure ventilation (PPV) at birth were randomized to resuscitation by SLMA or face mask. The primary outcome was the success rate of the resuscitation devices (SLMA or face mask) defined as the achievement of an effective PPV preventing the need for endotracheal intubation.

RESULTS

We enrolled 142 patients (71 in SLMA and 71 in face mask group, respectively). Successful resuscitation rate was significantly higher with the SLMA compared with face mask ventilation (91.5% vs 78.9%; P = .03). Apgar score at 5 minutes was significantly higher in SLMA than in face mask group (P = .02). Neonatal intensive care unit admission rate was significantly lower in SLMA than in face mask group (P = .02). No complications related to the procedure occurred.

CONCLUSIONS

In newborns with gestational age ≥34 weeks and/or expected birth weight ≥1500 g needing PPV at birth, the SLMA is more effective than face mask to prevent endotracheal intubation. The SLMA is effective in clinical practice after a short-term educational intervention.

TRIAL REGISTRATION

Registered with ClinicalTrials.gov: NCT01963936.

Feasibility of LMA Supreme for airway management in unconscious patients by ALS paramedics

Background

Airway management to ensure sufficient gas exchange is of major importance in emergency care. The accepted basic technique is to maintain an open airway and perform artificial ventilation in emergency situations is bag-valve mask (BVM) ventilation with manual airway management without airway adjuncts or with an oropharyngeal tube (OPA) only. Endotracheal intubation (ETI) is often referred to as the golden standard of airway management, but is associated with low success rates and significant insertion-related complications when performed by non-anaesthetists. Supraglottic devices (SADs) are one alternative to ETI in these situations, but there is limited evidence regarding the use of SAD in non-cardiac arrest situations. LMA Supreme (LMA-S) is a new SAD which theoretically has an advantage concerning the risk of aspiration due to an oesophageal inlet gastric tube port.

Methods

Forty paramedics were recruited to participate in the study. Adult (>18 years) patients, unconscious due to medical or traumatic cause with a GCS score corresponding to 3–5 and needed airway management were included in the study. Our aim was to study the feasibility of LMA-S as a primary airway method in unconscious patients by advanced life support (ALS) trained paramedics in prehospital care.

Results

Three regional Emergency Medical Service (EMS) services participated and 21 patients were treated during the survey. The LMA-S was placed correctly on the first attempt in all instances 21/21 (100%), with a median time to first ventilation of 9.8 s. Paramedics evaluated the insertion to be easy in every case 21/21 (100%). Because of air leak later in the patient care, the LMA-S was exchanged to an LT-D in two cases and to ETI in three cases (23.81%) by the paramedics. Regurgitation occurred after insertion two times out of 21 (9.52%) and in one of these cases (4.76%), paramedics reported regurgitation inside the LMA-S.

Conclusion

We conclude that the LMA-S seems to be relatively easy and quick to insert in unconscious patients by paramedics. However, we found out that there were ventilation related problems with the LMA-S. Further studies are warranted.

The LMA-Supreme versus the I-gel in simulated difficult airway in children: a randomised study

BACKGROUND

Supraglottic airway devices such as the LMA-Supreme (LMA-S) and I-gel, which have an additional lumen for the insertion of a gastric tube, can be useful in the management of the difficult airway.

OBJECTIVE

To test the performance of these two devices in the difficult paediatric airway.

DESIGN

Randomised double-blind study.

SETTING

Anaesthesia department, university hospital.

PATIENTS

Sixty American Society of Anesthesiologists (ASA) I-II children undergoing elective surgery.

INTERVENTION

After obtaining ethical approval and written informed consent from the parents, we compared the size 2 LMA-S with the I-gel in a simulated airway scenario made more difficult by using a cervical collar to limit mouth opening and neck movement.

MAIN OUTCOME MEASURES

The primary aim was to compare the oropharyngeal leak pressure of the LMA-S and the I-gel. The secondary aims were to compare success rate, insertion time, time to pass a gastric tube and fibreoptic view of the larynx.

RESULTS

Oropharyngeal leak pressure (mean ± SD) for the LMA-S was significantly higher than with the I-gel (20.9 ± 3.2 versus 18.9 ± 3.2 cmH2O, P = 0.019). First attempt success rate for the LMA-S was 100 and 90% for the I-gel (P > 0.05). Insertion time of the LMA-S was shorter than I-gel (11.2 ± 1.8 versus 13.5 ± 2.4 s, P = 0.001). Gastric tube placement was possible in all patients. The mean insertion time of the gastric tube was shorter with the LMA-S than with the I-gel (10.3 ± 3.6 versus 12.7 ± 3.2 s, P = 0.009). Fibreoptic laryngeal views were similar in both groups.

CONCLUSION

In the simulated difficult airway in children, both airway devices provided effective ventilation. Paediatric size 2 LMA-S sustained a higher airway pressure before leaking and was quicker to insert than the I-gel equivalent. These differences may not be clinically significant.

LMA Supreme for neonatal resuscitation: study protocol for a randomized controlled trial

Background

The most important action in the resuscitation of a newborn in the delivery room is to establish effective assisted ventilation. The face mask and endotracheal tube are the devices used to achieve this goal. Laryngeal mask airways that fit over the laryngeal inlet have been shown to be effective for ventilating newborns at birth and should be considered as an alternative to facemask ventilation or endotracheal intubation among newborns weighing >2,000 g or delivered ≥34 weeks’ gestation. A recent systematic review and meta-analysis of supraglottic airways in neonatal resuscitation reported the results of four randomized controlled trials (RCTs) stating that fewer infants in the group using laryngeal mask airways required endotracheal intubation (1.5%) compared to the group using face masks (12.0%). However, there were methodological concerns over all the RCTs including the fact that the majority of the operators in the trials were anesthesiologists.

Our hypothesis is based on the assumption that ventilating newborns needing positive pressure ventilation with a laryngeal mask airway will be more effective than ventilating with a face mask in a setting where neonatal resuscitation is performed by midwives, nurses, and pediatricians. The primary aim of this study will be to assess the effectiveness of the laryngeal mask airway over the face mask in preventing the need for endotracheal intubation.

Methods/design

This will be an open, prospective, randomized, single center, clinical trial. In this study, 142 newborns weighing >1,500 g or delivered ≥34 weeks gestation needing positive pressure ventilation at birth will be randomized to be ventilated with a laryngeal mask airway (LMA Supreme^TM, LMA Company, UK - intervention group) or with a face mask (control group). Primary outcome: Proportion of newborns needing endotracheal intubation. Secondary outcomes: Apgar score at 5 minutes, time to first breath, onset of the first cry, duration of resuscitation, death or moderate to severe hypoxic-ischemic encephalopathy within 7 days of life.

Trial registration

ClinicalTrials.gov identifier: NCT01963936 (October 11, 2013).

A prospective randomised controlled trial of the LMA Supreme vs cuffed tracheal tube as the airway device during percutaneous tracheostomy

We studied the performance of the LMA Supreme against a cuffed tracheal tube, our standard method of airway control during percutaneous tracheostomy, in 50 consecutive patients from three general critical care units. The primary outcome measure was adequacy of ventilation calculated as the difference in arterial carbon dioxide tension before and after tracheostomy. On an intention-to-treat analysis, there was no difference in the increase in arterial carbon dioxide tension between groups, with a median (IQR [range]) for the LMA Supreme of 0.9 (0.3-1.6 [0-2.8]) kPa, and for the tracheal tube of 0.8 (0.4-1.2 [0-2.5]) kPa, p = 0.82. Eight patients out of 25 (32%) crossed over from the LMA Supreme group to the tracheal tube group before commencement of tracheostomy due to airway or ventilation problems, compared with none out of 25 in the tracheal tube group, p = 0.01, and tracheostomy was postponed in two patients in the LMA Supreme group due to poor oxygenation. There were more clinically important complications in the LMA Supreme group compared with the tracheal tube group.

Extraglottic airway devices: A review

Extraglottic airway devices (EAD) have become an integral part of anesthetic care since their introduction into clinical practice 25 years ago and have been used safely hundreds of millions of times, worldwide. They are an important first option for difficult ventilation during both in-hospital and out-of-hospital difficult airway management and can be utilized as a conduit for tracheal intubation either blindly or assisted by another technology (fiberoptic endoscopy, lightwand). Thus, the EAD may be the most versatile single airway technique in the airway management toolbox. However, despite their utility, knowledge regarding specific devices and the supporting data for their use is of paramount importance to patient's safety. In this review, number of commercially available EADs are discussed and the reported benefits and potential pitfalls are highlighted.

Postoperative pharyngolaryngeal adverse events with laryngeal mask airway (LMA Supreme) in laparoscopic surgical procedures with cuff pressure limiting 25 cmH₂O: prospective, blind, and randomised study

To reduce the incidence of postoperative pharyngolaryngeal adverse events, laryngeal mask airway (LMA) manufacturers recommend maximum cuff pressures not exceeding 60 cmH₂O. We performed a prospective randomised study, comparing efficacy and adverse events among patients undergoing laparoscopic surgical procedures who were allocated randomly into low (limiting 25 cmH₂O, L group) and high (at 60 cmH₂O, H group) LMA cuff pressure groups with LMA Supreme. Postoperative pharyngolaryngeal adverse events were evaluated at discharge from postanaesthetic care unit (PACU) (postoperative day 1, POD 1) and 24 hours after discharge from PACU (postoperative day 2, POD 2). All patients were well tolerated with LMA without ventilation failure. Before pneumoperitoneum, cuff volume and pressure and oropharyngeal leak pressure (OLP) showed significant differences. Postoperative sore throat at POD 2 (3 versus 12 patients) and postoperative dysphagia at POD 1 and POD 2 (0 versus 4 patients at POD 1; 0 versus 4 patients at POD 2) were significantly lower in L group, compared with H group. In conclusion, LMA with cuff pressure limiting 25 cmH₂O allowed both efficacy of airway management and lower incidence of postoperative adverse events in laparoscopic surgical procedures. This clinical trial is registered with KCT0000334.

A novel modified laryngeal mask airway allowing full separation of the digestive and respiratory tracts, along with double-catheter ventilation, diagnosis, and treatment

The aim of this study was to design a novel, modified, multifunctional, and safe laryngeal mask airway (LMA). We designed an LMA with an internal catheter extending beyond the tip of the cuff. The protruding end of the internal catheter was provided with a catheter cuff, the space between the internal and external catheters was ventilatory, and the inlet ends of the 2 catheters were provided with standard connectors. We found that this design prevented reflux or aspiration of gastric content into the airway, prevented LMA dislocation, allowed ventilation through both the internal and external catheters, and allowed endoscopic examination and treatment of the gastrointestinal and respiratory tracts through both the internal and external catheters. This design overcomes the drawbacks and extends the functions of previous LMAs, offering a new approach to the development of LMAs.

The effect of changing the sequence of cuff inflation and device fixation with the LMA-Supreme® on device position, ventilatory complications, and airway morbidity: a clinical and fiberscopic study

BACKGROUND

The conventional sequence when using supraglottic airway devices is insertion, cuff inflation and fixation. Our hypothesis was that a tighter fit of the cuff and tip could be achieved with a consequently lower incidence of air leak, better separation of gastrointestinal and respiratory tracts and less airway morbidity if the device were first affixed and the cuff then inflated.

METHODS

Our clinical review board approved the study (public registry number DRKS00003174). An LMA Supreme® was inserted into 184 patients undergoing lower limb arthroscopy in propofol-remifentanil anaesthesia who were randomly assigned to either the control (inflation then fixation; n = 92) or study group (fixation then inflation; n = 92). The cuff was inflated to 60 cmH2O. The patients' lungs were ventilated in pressure-controlled mode with 5 cmH2O PEEP, Pmax to give 6 ml kg-1 tidal volume, and respiratory rate adjusted to end-tidal CO2 of 4.8 and 5.6 kPa. Correct cuff and tip position were determined by leak detection, capnometry trace, oropharyngeal leak pressure, suprasternal notch test, and lube-tube test. Bowl and cuff position and the presence of glottic narrowing were assessed by fiberscopic examination. Postoperative dysphagia, hoarseness and sore throat were assessed with a questionnaire. Ventilatory impairment was defined as a tidal volume < 6 ml kg-1 with Pmax at oropharyngeal leak pressure, glottic narrowing was defined as an angle between the vocal cords under 16 degrees.

RESULTS

The incidence of incorrect device position (18% vs. 21%), failed ventilation (10% vs. 9%), leak pressure (24.8 vs. 25.2 cmH2O, p = 0.63), failed lube-tube test (16.3% vs. 17.6%) and glottic narrowing (19.3% vs. 14.1%, p = 0.35) was similar in both groups (control vs. study, resp.). When glottic narrowing occurred, it was more frequently associated with ventilatory impairment in the control group (77% vs. 39%; p = 0.04). Airway morbidity was more common in the control group (33% vs. 19%; p < 0.05).

CONCLUSIONS

Altering the sequence of cuff inflation and device fixation does not affect device position, oropharyngeal leak pressures or separation of gastrointestinal and respiratory tracts. It reduces the incidence of glottic narrowing with impaired ventilation and also perioperative airway morbidity.

A randomized comparison of the laryngeal mask airway supreme™ and laryngeal mask airway unique™ in infants and children: does cuff pressure influence leak pressure?

BACKGROUND

The cuff pressure for optimal airway sealing with first-generation laryngeal mask airway has been shown to be 40 cm H(2)O in children. Currently, there are no data regarding the ideal intracuff pressure for the laryngeal mask airway Supreme (Supreme) in children.

OBJECTIVES

To compare the clinical performance of the laryngeal mask airway supreme with the laryngeal mask airway unique in infants and children.

MATERIALS AND METHODS

One hundred eighty children were assigned to receive either a Supreme or a laryngeal mask airway-U. We hypothesized higher airway leak pressure with the Supreme at both 40 cm H(2)O and 60 cm H(2)O, when compared with the laryngeal mask airway-U. Ease and time of insertion, insertion attempts, fiber optic examination, quality of airway, efficacy of mechanical ventilation, success of gastric tube placement (Supreme), incidence of gastric insufflation, and complications were also assessed.

RESULTS

Airway leak pressure at an intracuff pressure of 60 cm H(2)O for the Supreme was 17.4 (5.2) vs laryngeal mask airway-U at 18.4 (6.6) cm H(2)O and did not differ when compared to an intracuff pressure of 40 cm H(2)O for both devices; Supreme at 17.2 (5) vs laryngeal mask airway-U at 17.7 (6) cm H(2)O. The laryngeal mask airway-U was associated with higher first-attempt success rates. The Supreme was associated with less gastric insufflation than the laryngeal mask airway-U.

CONCLUSIONS

Intracuff pressures of 40 cm H(2)O may be sufficient for the Supreme in children, and there may be no added benefit of an intracuff pressure of 60 cm H(2)O, as leak pressures were similar. The Supreme may be preferred over the laryngeal mask airway-U for its lower rates of gastric insufflation and provision for gastric access when mechanical ventilation is utilized.

Predicted end-tidal sevoflurane concentration for insertion of a Laryngeal Mask Supreme: a prospective observational study

CONTEXT

The single-use Laryngeal Mask Airway (LMA) Supreme is a new supraglottic airway device. It has been reported to be reliable and easy-to-use in clinical practice; however, the anaesthetic techniques for its insertion are not standardised.

OBJECTIVES

The purpose of this study was to determine the ED50 of end-tidal sevoflurane concentration for successful LMA Supreme insertion without the use of neuromuscular blockade.

DESIGN

A prospective observational study.

SETTING

A single tertiary care surgical centre.

PATIENTS

Thirty-one consecutive elective patients scheduled for minor elective surgery under general anaesthesia.

INTERVENTION

Patients were preoxygenated with 100% oxygen and anaesthetised using normal tidal volume inhalation of sevoflurane. The target sevoflurane concentration was determined using a modified Dixon's 'up-and-down' method (starting at 2.5% with 0.5% as the step size). After the predetermined end-tidal concentration had been established and maintained for 10 min, LMA Supreme insertion was attempted.

MAIN OUTCOME MEASURE

The main outcome measure was the patient's response to LMA Supreme insertion, classified as either 'movement' or 'no movement'. The mean of the concentrations of seven cross-overs from 'movement' to 'no movement' was used to estimate the ED50.

RESULTS

The estimated sevoflurane concentration for successful LMA Supreme insertion in 50% of adults was 3.03 ± 0.75% (95% confidence interval 2.3 to 3.7%). The values of the ET50 and ET95 obtained by logistic regression were 2.83 and 5.30%, respectively.

CONCLUSION

Sevoflurane alone can provide acceptable conditions for insertion of the LMA Supreme in adults, at an estimated minimum alveolar anaesthetic concentration of 3% with minimal adverse effects.

A comparison of the performance of the I-gel™ vs. the LMA-S™during anesthesia: a meta-analysis of randomized controlled trials

BACKGROUND AND OBJECTIVE

Conflicting results were found between the I-gel™ and the LMA-Supreme™ during anesthesia, so we conducted a meta-analysis of randomized controlled trials (RCTs) to compare the effectiveness and safety of the I-gel™ vs. the LMA-Supreme™during anesthesia.

METHODS

A comprehensive search was conducted using Pubmed, EMbase, ISI Web of Knowledge, the Cochrane Library, China Journal Full-text Database, Chinese Biomedical Database, Chinese Scientific Journals Full-text Database, CMA Digital Periodicals, and Google scholar to find RCTs that compare the LMA-S™ with the i-gel™during anesthesia. Two reviewers independently selected trials, extracted data, and assessed the methodological qualities and evidence levels. Data were analyzed by RevMan 5.0 and comprehensive meta-analysis software.

RESULTS

Ten RCTs were included. There were no significant differences in oropharyngeal leak pressures (mean difference [MD] 0.72, 95% confidence interval [CI] -1.10 2.53), device placement time (MD -1.3, 95%CI -4.07 1.44), first attempt insertion success (risk ratio [RR] 1.01, 95% CI 0.9 1.14), grade 3 and 4 fiberoptic view (RR 0.89, 95%CI 0.65 1.21), and blood on removal (RR 0.62, 95%CI 0.32 1.22) between the i-gel™ and the LMA-Supreme™, respectively. However, the LMA-Supreme™was associated with easier gastric tube insertion (RR 1.17, 95%CI 1.07 1.29), and more sore throat (RR 2.56, 95%CI 1.60 4.12) than the i-gel™ group.

CONCLUSIONS

The LMA-Supreme™ and i-gel™ were similarly successful and rapidly inserted. However, the LMA-Supreme™ was shown to be easier for gastric tube insertion and associated with more sore throat compared with the i-gel™.

Comparison of Size 2 LMA-ProSeal™ and LMA-Supreme™ in Spontaneously Breathing Children: a Randomised Clinical Trial

OBJECTIVE

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.

STUDY DESIGN

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.

RESULTS

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).

CONCLUSION

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.

A randomized equivalence trial comparing the i-gel and laryngeal mask airway Supreme in children

BACKGROUND

The laryngeal mask airway Supreme (Supreme) is a new single-use supraglottic device with gastric access capability now available in all sizes for children.

OBJECTIVES

To compare the i-gel with the Supreme in children for routine airway maintenance.

MATERIALS/METHODS

One hundred and seventy children, aged 3 months to 11 years, 5-50 kg in weight, were randomly assigned to receive either the i-gel or the Supreme. The primary outcome measured was airway leak pressure. Secondary outcomes included the following: ease and time for insertion, insertion success rate, fiberoptic grade of view, ease of gastric tube placement, number of airway manipulations, quality of airway during anesthetic maintenance, and complications.

RESULTS

A total of 168 patients were assessed for the outcomes. The median (IQR [range]) airway leak pressure for the i-gel was higher than with the Supreme, 20 (18-25 [9-40]) cm H(2)O vs 17 (14-22 [10-40]) cm H(2)O, respectively (P = 0.001). There were no differences in the time for device insertion, fiberoptic grade of view, quality of airway, and complications. Median (IQR[range]) time of successful insertion of a gastric tube was faster with the Supreme, 12 (9.2-14.3 [5.2-44.2]) s than with the i-gel, 14 (11.9-19 [6.9-75]) s; P = 0.01. The number of airway manipulations during placement was higher with the i-gel than with the laryngeal mask airway Supreme (12 vs 13 patients), P = 0.02.

CONCLUSIONS

In infants and children, when a single-use supraglottic device with gastric access capabilities is required, the i-gel demonstrated higher airway leak pressures and can be a useful alternative to the Supreme.

The LMA-Supreme™ as an intubation conduit in patients with known difficult airways: a prospective evaluation study

BACKGROUND

Many extraglottic airway devices allow the direct passage of an adult-sized tracheal tube, but this is not possible with the LMA-Supreme(TM) . We evaluated the feasibility of using the LMA-Supreme(TM) as a conduit for intubation in patients with known difficult airways.

METHODS

Sixty-eight adult patients, with preoperative predictors of difficult intubation, were scheduled for elective surgery under general anaesthesia. After assessing the direct laryngoscopy view, 23 patients with Cormack-Lehane III/IV were included in the study. An LMA-Supreme(TM) was inserted, followed by the passage of a flexible bronchoscope loaded with an Aintree Intubation Catheter into the trachea. The bronchoscope and LMA-Supreme(TM) were removed, and a tracheal tube was railroaded over the Aintree Intubation Catheter into the trachea.

RESULTS

Tracheal intubation was successful in all patients using the above technique. SpO(2) was >95% during the intubation procedure.

CONCLUSIONS

We conclude that the LMA-Supreme(TM) is a successful conduit for bronchoscopic/Aintree Intubation Catheter-guided intubation in patients with known difficult airway.

The effect of a cervical collar on the seal pressure of the LMA Supreme™: a prospective, crossover trial

For personnel inexperienced in airway management, supraglottic airway devices may be the first choice in an emergency. Changing head position is known to reduce the seal pressure of a laryngeal mask airway. The aim of this study was to investigate whether the use of a cervical collar improves the stability of airways secured with the LMA Supreme™ (The Laryngeal Mask Company Limited, Mahé, Seychelles). In this crossover trial, the primary endpoint was the difference in the seal pressure of the LMA Supreme in anaesthetised patients in maximum passive extension of the neck, with and without a cervical collar. The median (IQR [range]) seal pressure was 18 (13.8-22.1 [0-30]) cmH(2) O in maximum passive extension without a cervical collar. With a cervical collar in place, the seal pressure increased to 28 (22.8-30 [17-30]) cmH(2) O (p<0.001). In the neutral head position, the seal pressure was 22 (17.6-24.5 [12-30]) cmH(2) O without and 27 (22-30 [12-30]) cmH(2) O with a cervical collar in place (p<0.001). We found that a cervical collar stabilises the airway with an LMA Supreme in place and we recommend this combination for (pre-hospital) emergency cases.

A cohort evaluation of the laryngeal mask airway-Supreme™ in children

OBJECTIVES

To assess the clinical performance of the laryngeal mask airway-Supreme in children.

AIM

The purpose of this prospective audit was to evaluate the feasibility of the laryngeal mask airway-Supreme in clinical practice and generate data for future comparison trials.

BACKGROUND

The laryngeal mask airway-Supreme is a new second-generation supraglottic airway that was recently released in limited pediatric sizes (sizes 1, 2).

METHODS

One hundred children, ASA I-III, newborn to 16 years of age, and undergoing various procedures requiring a size 1, 2, or 3 laryngeal mask airway-Supreme were studied. Assessments included insertion success rates, airway leak pressures, success of gastric tube insertion, quality of airway, and perioperative complications.

RESULTS

The first-time insertion success rate was 97%, with an overall insertion success rate of 100%. The mean initial airway leak pressure for all patients was 22.3 ± 6.6 cm H(2) O. Gastric tube placement was possible in 98% of patients. Complications were noted in six patients: coughing or laryngospasm (n = 3), sore throat (n = 1), and dysphonia (n = 2).

CONCLUSIONS

The laryngeal mask airway-Supreme was inserted with a high degree of success on the first attempt by clinicians with limited prior experience with the device. It was effectively used for a variety of procedures in children undergoing spontaneous and mechanical ventilation with minimal complications. The leak pressures demonstrated in this study, along with access for gastric decompression, suggest that the laryngeal mask airway-Supreme may be an effective device for positive pressure ventilation in children.

The LMA Supreme™ in 700 parturients undergoing Cesarean delivery: an observational study

BACKGROUND

The LMA Supreme™ (SLMA) is a single-use supraglottic device that provides a good seal for positive pressure ventilation. It has a double aperture design that facilitates the introduction of an orogastric tube to aspirate gastric contents. This observational study evaluated the role of the SLMA in parturients undergoing Cesarean delivery under general anesthesia.

METHODS

Non-obese parturients with at least four hours of fasting and antacid prophylaxis scheduled for uncomplicated Cesarean delivery were recruited from June 2009 through May 2010 at the Quanzhou Women's and Children's Hospital, China. We recorded the number of SLMA insertion attempts, the time to effective ventilation, the incidence of aspiration, and other anesthetic and obstetric outcomes. Postoperatively, we noted the presence of blood on the SLMA, postoperative sore throat, and patient satisfaction. Analysis included comparison of results between parturients having elective and urgent Cesarean delivery.

RESULTS

We recruited 700 parturients (576 elective, 124 urgent). Mean (standard deviation) body mass index was 25.6 (2.5) kg·m(-2). All SLMA insertions were successful, with 686 (98%) inserted on first attempt and a time to effective airway of 19.5 (3.9) sec. We maintained ventilation and oxygenation in all parturients with a good seal and there was no evidence of aspiration. Eighteen parturients (2.6%) had blood on the SLMA upon removal, 24 (3.4%) had sore throat, and patient satisfaction was 85 (7)%. These results were similar in elective and urgent cases.

CONCLUSIONS

In a carefully selected group of parturients, the SLMA is a useful alternative to tracheal intubation for Cesarean delivery, providing effective ventilation and a low incidence of side effects or complications.

Does a 4 diagram manual enable laypersons to operate the Laryngeal Mask Supreme®? A pilot study in the manikin

Background

Bystander resuscitation plays an important role in lifesaving cardiopulmonary resuscitation (CPR). A significant reduction in the "no-flow-time", quantitatively better chest compressions and an improved quality of ventilation can be demonstrated during CPR using supraglottic airway devices (SADs). Previous studies have demonstrated the ability of inexperienced persons to operate SADs after brief instruction. The aim of this pilot study was to determine whether an instruction manual consisting of four diagrams enables laypersons to operate a Laryngeal Mask Supreme^® (LMAS) in the manikin.

Methods

An instruction manual of four illustrations with speech bubbles displaying the correct use of the LMAS was designed. Laypersons were handed a bag containing a LMAS, a bag mask valve device (BMV), a syringe prefilled with air and the instruction sheet, and were asked to perform and ventilate the manikin as displayed. Time to ventilation was recorded and degree of success evaluated.

Results

A total of 150 laypersons took part. Overall 145 participants (96.7%) inserted the LMAS in the manikin in the right direction. The device was inserted inverted or twisted in 13 (8.7%) attempts. Eight (5.3%) individuals recognized this and corrected the position. Within the first 2 minutes 119 (79.3%) applicants were able to insert the LMAS and provide tidal volumes greater than 150 ml (estimated dead space). Time to insertion and first ventilation was 83.2 ± 29 s. No significant difference related to previous BLS training (P = 0.85), technical education (P = 0.07) or gender could be demonstrated (P = 0.25).

Conclusion

In manikin laypersons could insert LMAS in the correct direction after onsite instruction by a simple manual with a high success rate. This indicates some basic procedural understanding and intellectual transfer in principle. Operating errors (n = 91) were frequently not recognized and corrected (n = 77). Improvements in labeling and the quality of instructional photographs may reduce individual error and may optimize understanding.

The Laryngeal Mask Airway Supreme for positive pressure ventilation during laparoscopic cholecystectomy

STUDY OBJECTIVE

To evaluate the Laryngeal Mask Airway Supreme (SLMA) in patients undergoing laparoscopic cholecystectomy.

DESIGN

Prospective observational study.

SETTING

University-affiliated hospital.

PATIENTS

100 ASA physical status 1, 2, and 3 adult patients undergoing laparoscopic cholecystectomy with general anesthesia.

INTERVENTIONS

The SLMA was inserted in all study patients. Patients were placed in the reverse Trendelenburg position.

MEASUREMENTS

Ease of insertion of the device and the drain tube, oropharyngeal leak pressure, frequency of postoperative sore throat, and other adverse events were recorded. The surgeon scored stomach size on an ordinal scale of 0-10 at insertion of the laparoscope and before decompression of the pneumoperitoneum.

MAIN RESULTS

Insertion of the SLMA was successful in all patients (91 pts on the first attempt, 9 pts on the second attempt). Gastric tube insertion was successful in all patients (easy in 97 pts, difficult in 3 pts). Initial mechanical ventilation was adequate in all cases. Mean oropharyngeal leak pressure at the 60 cm H(2)O cuff pressure level was 28.8 cm H(2)O (±5.2; range 18-40 cm H(2)O). Mean airway pressure before pneumoperitoneum was 17.5 cm H(2)O (±3.3; cm; range 11-26 cm H(2)O) and 22.9 cm H(2)O (±4 cm; range 16-32 cm H(2)O) after pneumoperitoneum. Median (range) stomach size on insertion of the laparoscope and change in stomach size during surgery did not interfere with the procedure in any patient. Twelve patients (12%) complained of a mild sore throat postoperatively. No other complications were reported.

CONCLUSIONS

The SLMA is easy to insert and it is an effective ventilatory device for laparoscopic cholecystectomy.