Pharyngolaryngeal, neck, and jaw discomfort after anesthesia with the face mask and laryngeal mask airway at high and low cuff volumes in males and females

Efficacy and safety of three inflation methods of the laryngeal mask airway Ambu® Auraonce™: a randomized controlled study

The laryngeal mask airway (LMA) is commonly used for airway management. Cuff hyperinflation has been associated with complications, poor ventilation and increased risk of gastric insufflation. This study was designed to determine the best cuff inflation method of AuraOnce™ LMA during bronchoscopy and EBUS (Endobronquial Ultrasound Bronchoscopy) procedure. We designed a Randomized controlled, doble-blind, clinical trial to compare the efficacy and safety of three cuff inflation methods of AuraOnce™ LMA. 210 consenting patients scheduled for EBUS procedure under general anesthesia, using AuraOnce™ LMA were randomized into three groups depending on cuff insufflation: residual volume (RV), half of the maximum volume (MV), unchanged volume (NV). Parameters regarding intracuff pressure (IP), airway leak pressure (OLP), leakage volume (LV) were assessed, as well as postoperative complications (PC). 201 (95.7%) patients completed the study. Mean IP differed between groups (MV: 59.4 ± 32.4 cm H2O; RV: 75.1 ± 21.1 cm H2O; NV: 83.1 ± 25.5 cmH20; P < 0.01). The incidence of IP > 60 cmH2O was lower in the MV group compared to the other two (MV: 20/65(30.8%); RV:47/69 (68.1%); NV 48/67 (71.6%); p < 0.01). The insertion success rate was 89,6% (180/201) at first attempt, with no difference between groups (p = 0.38). No difference between groups was found either for OLP (p = 0.53), LV (p = 0.26) and PC (p = 0.16). When a cuff manometer is not available, a partial inflation of AuraOnce™ LMA cuff using MV method allows to control intracuff pressure, with no significant changes of OLP and LV compared to RV and NV insufflation method.Registration clinical trial: NCT04769791.

Contrast of oropharyngeal leak pressure and clinical performance of I-gel™ and LMA ProSeal™ in patients: A meta-analysis

BACKGROUND

Conflicting outcomes have been reported for the i-gel™ and laryngeal mask airway (LMA) ProSeal™ in children and adults during general anesthesia. Randomized controlled trials (RCTs) that yielded wide contrast outcomes between i-gel™ and LMA ProSeal™ were included in this meta-analysis.

METHODS

Two authors independently identified RCTs that compared i-gel™ with LMA ProSeal™ among patients receiving general anesthesia by performing searches in EMBASE, Cochrane, PubMed, and ScienceDirect. Discussion was adopted to resolve disagreements. Data were counted with Review Manger 5.3 and pooled by applying weighted mean difference (MD) and rlsk ratio (RR), and related 95% confidence intervals.

RESULTS

A total of 33 RCTs with 2605 patients were included in the meta-analysis. I-gel™ provided a considerably lower oropharyngeal leak pressure [weighted average diversity (MD) = -1.53 (-2.89, -0.17), P = 0.03], incidence of blood staining on the supraglottic airway devices [RR = 0.44, (0.28, 0.69), P = 0.0003], sore throat [RR = 0.31 (0.18, 0.52), P<0.0001], and a short insertion time [MD = -5.61 (-7.71, -3.51), P<0.00001] than LMA ProSeal™. Compared with LMA ProSeal™, i-gel™ offered a significantly higher first-insertion success rate [RR = 1.03 (1.00, 1.06), P = 0.03] and ease of insertion [RR = 1.06 (1.01, 1.11), P = 0.03]. The gastric-tube-placement first insertion rate [RR = 1.04 (0.99, 1.10), P = 0.11], laryngospasm [RR = 0.76 (0.17, 3.31), P = 0.72], and cough [RR = 1.30 (0.49, 3.44), P = 0.60] between the two devices were similar.

CONCLUSIONS

Both devices could achieve a good seal to provide adequate ventilation. Compared with the used LMA ProSeal™, the i-gel™ was found to have fewer complications (blood stainning, sore throat) and offers certain advantages (short insertion time, higher first-insertion success rate and ease of insertion) in patients under general anesthesia.

Anesthesiology trainees performing flexible scope intubation in spontaneously breathing patients in the left lateral position and the supine position: a prospective randomized trial

Background

Flexible scope intubation is an important airway management skill that requires hands-on training in a real airway. We compared flexible scope intubation by trainees between patients in the left lateral and supine positions.

Methods

Forty patients aged 20 to 80 years with American Society of Anesthesiologists physical status class I to III were scheduled for elective surgery under general endotracheal anesthesia in Ramathibodi Hospital from February 2020 to June 2020. Patients were randomly assigned to be intubated in one of two positions: supine (Group S) or left lateral (Group L). Trainees performed flexible scope intubation in sedated patients under the supervision of an attending anesthesiologist. Intubation success, time to successful intubation, number of attempts, airway adjustment maneuvers, and hemodynamic changes were compared between groups.

Results

Patient characteristics did not differ between groups except for Mallampati airway classification. The rate of successful intubation on the first attempt and intubation time did not significantly differ between groups. The proportion of patients who required a jaw thrust during intubation was significantly lower in Group L (10.5% vs. 85%; P < 0.01). Blood pressure and oxygen saturation declined in both groups after intubation. The relative risk of desaturation in patients in the left lateral position compared with the supine position was 0.44 (0.1649–1.1978).

Conclusion

The rate of successful flexible scope intubation on the first attempt and intubation time did not differ between the groups. The proportion of patients who required a jaw thrust maneuver was significantly lower in patients in the left lateral position.

Trial registration

https://www.thaiclinicaltrials.org/ (TCTR20200208001) on 08/02/2020.

Pharyngolaryngeal Morbidity With the Laryngeal Mask Airway SupremeTM at Different Fiberoptic Bronchoscopy Grades: An Observational Study

OBJECTIVE

To assess whether the different fiberoptic bronchoscopy (FOB) grades of laryngeal mask airway (LMA) Supreme™ affects pharyngolaryngeal morbidity (PLM, including sore throat, dysphonia, pharyngoxerosis, and dysphagia) after general anesthesia.

METHODS

A total of 235 adult patients scheduled for elective laser lithotripsy undergoing general anesthesia with the placement of LMA Supreme™ were enrolled. The position of LMA Supreme™ was assessed by FOB and categorized into five grades. Meanwhile, patients were divided into four groups (grades A-D); none was assessed as grade E. We collected blinded data on PLM at 2 (H+2), 6 (H+6), and 24 hours (H+24) postoperatively. The incidence and severity of PLM as the primary outcome and incidence of PLM at three time points as a secondary outcome were compared.

RESULTS

The incidence of PLM was higher at 2 and 6 hours than at 24 hours; however, no significant difference was found between the incidence of PLM in the FOB groups. Furthermore, the severity of sore throat and dysphonia between groups were obviously differed at H+6 and H+24, but similar at H+2. The severity of postoperative pharyngoxerosis and dysphagia were similar between groups at three time points.

CONCLUSIONS

A positive association was found between the severity of postoperative sore throat and dysphonia and FOB grade after LMA Supreme™ placement. PLM secondary to placement of the LMA Supreme™ was short lasting.

Comparison of LMA supreme, i-gel, and baska mask for airway management during laparoscopic cholecystectomy: A prospective randomized comparative study from North India

Background:

The supraglottic airway device (SAD) has proved to be an appropriate alternative to endotracheal intubation in laparoscopic surgeries owing to various advantages, namely, decreased airway manipulation and stable hemodynamics.

Aims:

We compared the efficacy in terms of oropharyngeal leak pressure (OLP) and safety of laryngeal mask airway (LMA)-Supreme (LMA-S), i-gel, and Baska mask in patients undergoing laparoscopic cholecystectomy.

Settings and Design:

Ninety patients posted for elective laparoscopic cholecystectomy were selected for a prospective randomized comparative study in a tertiary care center.

Materials and Methods:

The study comprised three groups of 30 each based on the different SADs used Group-LS with LMA-Supreme, Group-IG with i-gel, and Group-BM with Baska mask. The secondary objectives were device insertion time, ease of insertion, changes in the peak airway pressure (PAP), heart rate, mean arterial pressure, and airway complications (sore throat, dysphagia. dysphonia, lip/tongue or dental injury, etc.) between three groups.

Statistical Analysis:

The quantitative data were analyzed using the one-way analysis of variance test and Bonferroni post hoc multiple comparison test. Qualitative data were compared using Chi.squared test

Results:

OLP was significantly higher (P = 0.005) in the Baska mask than i-gel and LMA-S groups just after insertion and during carboperitonium. There was no significant difference in time for device insertion, number of attempts, ease of insertion, and use of manipulation (P > 0.05). However, the gastric tube insertion time was significantly lower in Group BM (9.59 ± 2.78) than Group IG with 12.79 ± 3.47 and Group LS with 10.84 ± 3.68 (P < 0.05). There were no significant differences between the groups with regard to changes in the PAP, heart rate, mean arterial pressure at different time intervals, and complications.

Conclusion:

Baska mask provided a significantly higher OLP compared to i-gel and LMA-S without significant airway morbidity in laparoscopic surgeries.

Influence of two-handed jaw thrust during tracheal intubation on postoperative sore throat: a prospective randomised study

Objective

General anaesthesia with tracheal intubation results in sore throat. We evaluated the influence of the two-handed jaw thrust on postoperative sore throat in patients who require tracheal intubation.

Methods

In this prospective, double-blind, single-centre, parallel-arm, and randomised trial, 92 patients who were scheduled for general anaesthesia for total hip arthroplasty were allocated to one of two groups. In the jaw thrust group (n = 46), the two-handed jaw thrust manoeuvre was applied at intubation. In the control group (n = 46), conventional intubation with sham jaw thrust was performed. Incidences of airway morbidities including sore throat, hoarseness, and cough at 2, 4, and 24 hours postoperatively were compared.

Results

During the postoperative 24 hours, the incidence of sore throat (8 [17%] vs. 20 [44%]) and hoarseness were lower in the jaw thrust group (8 [17%] vs. 18 [39%]) compared with the control group. The incidence of cough during the postoperative 24 hours was similar between the groups.

Conclusions

The jaw thrust manoeuvre significantly reduced sore throat and hoarseness in patients after general anaesthesia using tracheal intubation.

Clinical trial registration: NCT 03568279.

Incidence of gastric insufflation at high compared with low laryngeal mask cuff pressure: A randomised controlled cross-over trial

BACKGROUND

The success of ventilation with a laryngeal mask depends crucially on the seal between the mask and the periglottic tissue. Increasing the laryngeal mask's cuff volume is known to reduce oral air leakage but may lead to gastric insufflation.

OBJECTIVE

We hypothesised that a lower cuff pressure would result in less gastric insufflation. We sought to compare gastric insufflation with laryngeal mask cuff pressures of 20 cmH2O (CP20) and 60 cmH2O (CP60) during increasing peak airway pressures in a randomised controlled double-blind cross-over study. We also evaluated the incidence of gastric insufflation at the recommended peak airway pressure of 20 cmH2O or less and during both intermittent positive airway pressure and continuous positive airway pressure.

METHODS

After obtaining ethics approval and written informed consent, 184 patients ventilated via laryngeal mask received a stepwise increase in peak airway pressure from 15 to 30 cmH2O with CP20 and CP60 in turn. Gastric insufflation was determined via real-time ultrasound and measurement of the cross-sectional area of the gastric antrum. The primary endpoint was the incidence of gastric insufflation at the different laryngeal mask cuff pressures.

RESULTS

Data from 164 patients were analysed. Gastric insufflation occurred less frequently at CP20 compared with CP60 (P < 0.0001). Gastric insufflation was detected in 35% of cases with CP20 and in 48% with CP60 at a peak airway pressure of 20 cmH2O or less. Gastric insufflation occurred more often during continuous than during intermittent positive airway pressures (P < 0.01).

CONCLUSION

A laryngeal mask cuff pressure of 20 cmH2O may reduce the risk of gastric insufflation during mechanical ventilation. Surprisingly, peak airway pressure of 20 cmH2O or less may already induce significant gastric insufflation. Continuous positive airway pressure should be avoided due to an increased risk of gastric insufflation.

CLINICAL TRIAL REGISTRATION

The study was registered in the German Clinical Trials Register (DRKS00010583) https://www.drks.de.

A comparison of laryngeal mask airway-supreme and endotracheal tube use with respect to airway protection in patients undergoing septoplasty: a randomized, single-blind, controlled clinical trial

BACKGROUND

There are doubts among anesthesiologists on the use of the Laryngeal Mask Airway (LMA) in nasal surgeries because of concerns about the occurrence of blood leakages to the airway. We hypothesized that the use of LMA-Supreme (LMA-S) in nasal surgery is comparable with endotracheal tube (ETT) according to airway protection against blood leakage through the fiberoptic bronchoscopy, oropharyngeal leakage pressure (OLP), heart rate (HR), mean arterial pressure (MAP), and postoperative adverse events.

METHODS

The present study was conducted in a prospective, randomized, single-blind, controlled manner on 80 patients, who underwent septoplasty procedures under general anesthesia, after dividing them randomly into two groups according to the device used (LMA-S or ETT). The presence of blood in the airway (glottis/trachea, distal trachea) was analyzed with the fiberoptic bronchoscope and a four-point scale. Both groups were evaluated for OLP; HR; MAP; postoperative sore throat, nausea, and vomiting; dysphagia; and dysphonia.

RESULTS

In the fiberoptic evaluation of the airway postoperatively, less blood leakage was detected in both anatomic areas in the LMA-S group than in the ETT group (glottis/trachea, p = 0.004; distal trachea, p = 0.034). Sore throat was detected less frequently in the LMA-S group at a significant level in the 2nd, 6th, and 12th hours of postoperative period; however, other adverse events were similar in both groups. Hemodynamic parameters were not different between the two groups.

CONCLUSION

The present findings demonstrate that the LMA-S provided more effective airway protection than the ETT in preventing blood leakage in the septoplasty procedures. We believe that the LMA-S can be used safely and as an alternative to the ETT in septoplasty cases.

TRIAL REGISTRATION

This trial is registered at the US National Institutes of Health ( ClinicalTrials.gov ) # NCT03903679 on April 5, 2019.

Clinical Outcomes of a Modified Laryngeal Mask Airway (LMA® Gastro™ Airway) During Esophagogastroduodenoscopy in Children and Adolescents: A Randomized Study

Introduction

During esophagogastroduodenoscopy (EGD), general anesthesia (GA) may be provided using a laryngeal mask airway (LMA) with the endoscope inserted behind the cuff of the LMA into the esophagus. Passage of the endoscope may increase the intracuff of the LMA. We evaluated a newly designed LMA (LMA^® Gastro™ Airway) which has an internal channel exiting from its distal end to facilitate EGD. The current study compared the change of LMA cuff pressure between this new LMA and a standard clinical LMA (Ambu^® AuraOnce™) during EGD.

Methods

Patients less than 21 years of age and weighing more than 30 kg were randomized to receive airway management with one of the two LMAs during EGD. After anesthetic induction and successful LMA placement, the intracuff pressure of the LMAs was continuously monitored during the procedure. The primary outcome was the change of intracuff pressure of the LMAs.

Results

The study cohort included 200 patients (mean age 13.6 years and weight 56.6 kg) who were randomized to the LMA^® Gastro™ Airway (n=100) or the Ambu^® AuraOnce™ LMA (n=100). Average intracuff pressures during the study period (before and after endoscope insertion) were not different between the two LMAs. Ease of the procedure was slightly improved with the LMA^® Gastro™ Airway (p<0.001).

Discussion

The LMA^® Gastro™ Airway blunted, but did not prevent an increase in intracuff pressure during EGD when compared to the Ambu^® AuraOnce™ LMA. Throat soreness was generally low, and complications were infrequent in both groups. The ease of the procedure was slightly improved with the LMA^® Gastro™ Airway compared to the Ambu^® AuraOnce™ LMA.

Effects of Peak Inspiratory Pressure-Guided Setting of Intracuff Pressure for Laryngeal Mask Airway Supreme™ Use during Laparoscopic Cholecystectomy: A Randomized Controlled Trial

PURPOSE

To determine the effects of peak inspiratory pressure (PIP)-guided intracuff pressure (ICP) modulation of laryngeal mask airway (LMA) Supreme™ during laparoscopic cholecystectomy.

METHODS

Totally 120 patients were randomly divided using computer-generated numbers into a control group (n = 60; ICP, 60 cmH₂O) and a PIP group (n = 60), in which ICP was increased with 5 cmH₂O each time from PIP level until no air leaks from the oropharynx. PIP, ICP, cuff volume (CV), oropharyngeal leak pressure (OLP) and leak fraction (LF) were recorded before and after pneumoperitoneum establishment. Postoperative pharyngolaryngeal complications (sore throat, dysphagia, pharyngeal hematoma, and dysphonia) were also recorded.

RESULTS

Demographic data were similar in the two groups. The CV and ICP before and after pneumoperitoneum were significantly lower in the PIP group (CV: 15.6 ± 2.3 mL and 21.0 ± 2.6 mL; ICP: 14.3 ± 2.9 cmH₂O and 20.5 ± 3.4 cmH₂O) than in the control group (CV: 33.0 ± 2.8 mL and 32.8 ± 1.9 mL; ICP: 60.0 ± 0.1 cmH₂O and 60.0 ± 0.1 cmH₂O) (P < 0.05). Although OLP was lower in the PIP group (P < 0.05), the LF was similar in the two groups (P > 0.05). There were fewer postoperative pharyngolaryngeal complications in the PIP group (P < 0.05).

CONCLUSIONS

Compared with a fixed ICP of 60 cmH₂O, PIP-guided ICP modulation during LMA Supreme™ use provided effective airway sealing at a lower CV and ICP, and produced fewer postoperative pharyngolaryngeal complications in patients undergoing laparoscopic cholecystectomy.

Comparison of clinical performance of i-gelⓇ and Baska MaskⓇ during laparoscopic cholecystectomy

BACKGROUND

The supraglottic airway device is an appropriate alternative to tracheal intubation in laparoscopic surgery. We compared the Baska MaskⓇ with i-gelⓇ by measuring the oropharyngeal leak pressure (OLP) and hemodynamic and respiratory parameters during laparoscopic cholecystectomy.

METHODS

A total of 97 patients were randomly allocated to either i-gel group (n = 49) or Baska Mask group (n = 48). Insertion time, number of insertion attempts, fiber-optic view of the glottis, and OLP were recorded. Heart rate, mean arterial pressure, peak airway pressure (PAP), lung compliance, and perioperative complications were assessed before, during, and after pneumoperitoneum.

RESULTS

There were no significant differences between the two groups regarding demographic data, insertion time, fiber-optic view of the glottis, and the use of airway manipulation. The OLP was higher in the Baska Mask group than in the i-gel group (29.6 ± 6.8 cmH2O and 26.7 ± 4.5 cmH2O, respectively; P = 0.014). Heart rate, mean arterial pressure, PAP, and lung compliance were not significantly different between the groups. The incidence of perioperative complications was small and not statistically significant.

CONCLUSIONS

Both the i-gel and Baska Mask provided a satisfactory airway during laparoscopic cholecystectomy. Compared with the i-gel, the Baska Mask demonstrated a higher OLP.

A randomised controlled trial of the effect of laryngeal mask airway manometry on postoperative sore throat in spontaneously breathing adult patients presenting for surgery at a university teaching hospital

Background

Laryngeal mask airways (LMAs) are widely used in anaesthesia and are considered to be generally safe. Postoperative sore throat (POST) is a frequent complication following LMA use and can be very distressing to patients. The use of an LMA cuff pressure of between 30 and 32cm of H₂O in alleviating post-operative sore throat has not been investigated.

Objective

To compare the occurrence of POST between the intervention group in which LMA cuff pressures were adjusted to 30–32cm of H₂O and the control group in which only monitoring of LMA cuff pressures was done, to compare the severity of POST between the two study groups and to compare the LMA cuff pressures between the two study groups.

Methods

Eighty consenting adult patients scheduled to receive general anaesthesia with use of an LMA were randomized into two groups of 40 patients each. Intervention group: LMA airway cuff pressures were adjusted to 30 to 32cm of H₂O. Control group: Only had LMA cuff pressures monitored throughout the surgery. All patients were interviewed postoperatively at two, six and twelve hours. Data of their baseline characteristics, occurrence and severity of POST was collected. If POST was present; a Numerical Rating Scale (NRS) was used to assess the severity. Cuff pressures between the two study groups were also determined.

Results

The baseline demographic characteristics of the participants were similar. The use of manometry to limit LMA AMBU® AuraOnce™ intracuff pressure to 30–32cm H₂O reduced POST in surgical patient's by 62% at 2 hours and 6 hours (Risk Ratio 0.38 95%CI 0.21–0.69)in the intervention group. The median POST pain score in the intervention group was significantly lower than the control group with scores of 0 at 2, 6 and 12 hours post operatively. Routine practice of LMA cuff inflation by anesthesiologists is variable, and the intracuff pressures in the control group were higher than in the intervention group. (P<0.001)

Conclusion

Among this population, reduction of LMA AMBU® AuraOnce™ intracuff pressure to 30–32cm H₂O reduces the occurrence and severity of POST. The LMA cuff pressures should be measured routinely using manometry and reducing the intracuff pressures to 30–32 cm of H₂O recommended as best practice.

Randomized Evaluation of the Single-use SoftSeal™ and the Re-useable LMA Classic™ Laryngeal Mask

A number of laryngeal masks are available, including both re-usable and single-use masks. Single-use laryngeal masks may decrease the risk of transmitting prion infections. We performed a single-blind randomized trial in 200 spontaneously breathing female patients under general anaesthesia with nitrous oxide, to compare a new single-use laryngeal mask, the SoftSeal™ (Portex Ltd, U.K.), with a re-usable laryngeal mask, the LMA Classic™ (Laryngeal Mask Company Ltd., Cyprus). The primary outcome was successful insertion at the first attempt. Size 4 single-use (n=99) or re-usable (n=100) laryngeal masks, inserted by experienced anaesthetists, were equivalent for successful placement at the first attempt (90% versus 91% respectively). The single-use mask was less easy to insert (47% difficult versus 9%, P<0.001). Clinical and anatomical tests of position and function were similar. The cuff pressure of the re-usable mask increased significantly compared with the single-use mask (median +10 cm versus –2 cm H 2 O, P<0.001). Forty per cent of patients allocated the single-use mask and 20% of those allocated the re-usable mask experienced sore throat at 24 hours postoperatively (P<0.05). An estimation of cost per patient use was greater for the re-usable mask.

We conclude that the SoftSeal™ single-use laryngeal mask and the LMA Classic™ re-usable laryngeal mask airway are of similar clinical utility in terms of successful insertion and airway maintenance. The re-usable laryngeal mask was easier to insert and associated with less postoperative sore throat, but costs were higher.

Evaluation of the SLIPA™ (Streamlined Liner of the Pharynx Airway), a Single Use Supraglottic Airway Device, in 60 Anaesthetized Patients Undergoing Minor Surgical Procedures

The Streamlined Liner of the Pharyngeal Airway, SLIPA™ (Hudson RCI) is a new disposable supraglottic airway device that has no inflatable cuff and has features designed to reduce aspiration risk. This study aimed to assess the insertion success and effectiveness of the SLIPA™ in 60 patients who presented for elective surgery. Ethics committee approval was obtained. Patients were excluded if they were less than 18 years, had not provided written consent or were at risk of pulmonary aspiration. The first 20 SLIPA™ were inserted by the principal investigator (Group A) followed by another 40 inserted by medical officers and anaesthetists of varying experience (Group B). Twenty-one males and 39 females were recruited into the study. Median time to ventilation was 20.4 seconds in Group A (range 12.9-109) and 24.8 seconds in Group B (range 8.2-82.5). Overall success rate was 100% in Group A and 92.5% in Group B. The lowest recorded SpO2 was 91% in Group B. The incidence of blood and sore throat score >3 (0-10 scale) was 23% and 7% respectively (Groups A and B). Group B reported that use of the device was very easy in 16%, easy in 76%, difficult in 5%, and very difficult in 3%. The SLIPA™ proved to be a reliable airway providing adequate ventilation in both spontaneous breathing and assisted respiration. Most users found the SLIPA™ to be easy or very easy to use.

Comparison of the Re-usable LMA Classic™ and Two Single-use Laryngeal Masks (LMA Unique™ and SoftSeal™) in Airway Management by Novice Personnel

In a single-blind randomized trial, three types of laryngeal masks: the reusable LMA Classic™, the single-use LMA Unique™ and SoftSeal™ were inserted by novice medical officers in anaesthesia. Five successive attempts were undertaken with each mask type. The order of the mask type insertion was randomly selected. Mean (SD) insertion times for LMA Classic™, LMA Unique™ and Soft Seal™ were 32.9 (12.3), 39.6 (23.4) and 49.4 (50.4) seconds respectively. Differences were only significant between LMA Classic™ and SoftSeal™ (P=0.012). There were no significant differences in first attempt success rates (LMA Classic™ 80%, LMA Unique™ 77% and SoftSeal™ 62%). The SoftSeal™ was most frequently associated with blood on the mask (32%) compared to the LMA Unique™(9%) and LMA Classic™ (6%). Sore throat was experienced in 14% of patients in the LMA Unique™ group versus 41% and 42% in the LMA Classic™ and SoftSeal™ groups respectively. Mean±SD oropharyngeal leak pressure was significantly higher in the SoftSeal™ (21±6 cmH2O) compared to the LMA Classic™ (17±7 cmH2O) and LMA Unique™ (16±6 cmH2O).

Novice medical doctors can be taught to insert disposable laryngeal masks. The SoftSeal™ took longer to insert, which resulted in a higher incidence of blood on the mask, but success rates did not differ. The LMA Unique™ was associated with the lowest incidence of sore throat in the immediate postoperative period. A higher oropharyngeal leak pressure with the SoftSeal™ may indicate improved airway seal and protection against aspiration.

Comparison of the clinical performance of airway management with the i-gel® and laryngeal mask airway SupremeTM in geriatric patients: a prospective and randomized study

Background

Geriatric patients are susceptible to respiratory and hemodynamic adverse events during endotracheal intubation and extubation due to anatomic and physiological changes with aging. Supraglottic airway devices (SADs) provide reduced airway morbidity and increased hemodynamic stability in adults. However, studies that have compared the clinical performance of SADs in geriatric patients are limited. Therefore, we evaluated the clinical performance of airway management with i-gel^® and laryngeal mask airway Supreme (LMA Supreme^TM) in geriatric patients.

Methods

The subjects were American Society of Anesthesiologists physical status classification I–III geriatric (65–85 years) patients who underwent elective surgery with general anesthesia and were randomly allocated into the i-gel^® group and the LMA Supreme^TM group. We compared the time for successful insertion on a first attempt as a primary outcome, and the secondary outcomes were success rate, ease of insertion, maneuver for successful ventilation, oropharyngeal leak pressure, gastric insufflation, fiberoptic view grades, ventilator problems, and adverse events.

Results

Insertion time was significantly shorter for the i-gel^® than the LMA Supreme^TM (21.4 ± 6.8 vs. 29.3 ± 9.9 s; P = 0.011). The i-gel^® was also easier to insert than the LMA Supreme^TM (P = 0.014). Gastric insufflation was less frequent with the i-gel^® than the LMA Supreme^TM (0% vs. 31.3%; P = 0.013). Other measurements were comparable between groups.

Conclusions

Both devices can be safely applied to geriatric patients with similar success rates and oropharyngeal leak pressures. However, inserting the i-gel^® was faster and easier compared to the LMA Supreme^TM in geriatric patients.

Clinical application of limiting laryngeal mask airway cuff pressures utilizing inflating syringe intrinsic recoil

BACKGROUND

Overinflation of the laryngeal mask airway (LMA) cuff may cause many of the complications associated with the use of the LMA. There is no clinically acceptable (cost effective and practical) method to ensure cuff pressure is maintained below the manufacturer's recommended maximum value of 60 cm H2O (44 mmHg). We studied the use of the intrinsic recoil of the LMA inflating syringe as an effective and practical way to limit cuff pressures at or below the manufacturer's recommended values.

METHODS

We enrolled 332 patients into three separate groups: LMAs inserted and inflated per standard practice at the institution with only manual palpation of the pilot balloon; LMA cuff pressures measured by a pressure transducer and reduced to < 60 cm H2O (44 mmHg); and LMA intra-cuff pressure managed by the intrinsic recoil of the syringe.

RESULTS

There were no statistically significant differences between the pressure transducer group and the syringe recoil group for initial cuff pressure or cuff pressure 1 hour after surgery. Both the syringe recoil group and pressure transducer group were less likely than the standard practice group to have sore throat and dysphagia 1 hour after surgery. These differences remained 24 hours after surgery.

CONCLUSIONS

Syringe recoil provides an efficient and reproducible method similar to manometry in preventing overinflation of the LMA cuff and decreasing the incidence of postoperative laryngopharyngeal complications.

Comparison of Different Cuff Pressure Use with the Supreme Laryngeal Mask Airway on Haemodynamic Response, Seal Pressure and Postoperative Adverse Events: A Prospective Randomized Study

Objective

The Supreme™ laryngeal mask airway (SLMA) is a supra glottic airway (SGA) device that is used as an alternative to endotracheal tubes. In the present study, we aimed to compare the use of the SLMA with normal cuff pressure and low cuff pressure, primarily for haemodynamic response.

Methods

In the present study, 120 patients diagnosed with hypertension and scheduled for varicose vein or inguinal hernia operation were enrolled and 99 patients finished. Using randomization, patients were divided into two groups according to cuff pressure as a low-pressure group (Group L, 45 cm H₂O) and a normal-pressure group (Group N, 60 cm H₂O). Demographics, Mallampati score and the type and duration of surgery, heart rate (HR), mean arterial pressure (MAP), percentage of tidal volume leakage, Ppeak, Pmean, etCO₂, seal pressure, fibreoptic scores and postoperative adverse effects of all patients were recorded.

Results

MAP and HR values immediately and 2 minutes after SLMA insertion were significantly lower in Group L (p<0.001). In Group L and Group N, the seal pressures were 24.1±3.1 cm H₂O and 26.2±3.9 cm H₂O, respectively (p=0.003). Also, blood staining and sore throat occurred less frequently in Group L (p<0.05). The fibreoptic average score, insertion features and ventilation parameters were similar between the groups (p>0.05).

Conclusion

SLMA use with a cuff pressure of 45 cm H₂O significantly decreases haemodynamic response and post-operative side effects compared with a normal cuff pressure. Therefore, except for some specific surgeries that require higher seal pressures, we recommend the use of the SLMA with cuff pressures as low as 45 cm H₂O.

Comparison of I-gel versus Endotracheal Tube in Patients Undergoing Elective Cesarean Section: A Prospective Randomized Control Study

Background and Aim:

Physiological changes during pregnancy and the sympatho adrenalstimulation during larynoscopy and intubation leads to evaluation of safe devices to secure airway during cesarean section under general anesthesia. I-gel, recently emerging effective supra glottic device found safe during general anesthesia in cesarean section. Aim of the study is to compare the hemodynamic disturbances and airway related complications of I-gel and Endotracheal tube in patients undergoing cesarean section under general anesthesia.

Material and Methods:

Eighty ASA II pregnant patients posted for elective LSCS were randomly divided into two groups of 40 each (n = 40). According to the group they were inserted either I-gel (Group I) or ETT (Group E). Insertion time, ease of intubation, hemodynamics during insertion and Extubation, airway related complications like sore throat, blood on the device, dysphagia, regurgitation, nausea, vomiting, aspiration and laryngospasm were noted and compared. Statistical analysis was done by using unpaired t test, chi square test and fisher's test. P value of <0.05 was considered as significant.

Results:

The demographic parameters, ease of insertion, insertion times and adequacy of ventilation were comparable between the groups (P > 0.05). 8 out of 40 patients in Group E had difficult intubation (P < 0.01). More than 20% of rise in MAP and HR were found during intubation and Extubation in Group E (40 out of 40 patients) which was statistically significant when compared to Group I (P < 0.001). Post operative sore throat significantly high in Group E (30 out of 40) (P < 0.001) when compared to Group I (4 out of 40).

Conclusion:

Easier insertion with less hemodynamic disturbances and very low incidence of sore throat I-gel found to be safer device to secure the airway in patients undergoing LSCS under general anesthesia.

The effect of esophagogastroduodenoscopy probe insertion on the intracuff pressure of airway devices in children during general anesthesia

Given the size of the esophagogastroduodenoscopy (EGD) probe and the compressibility of the pediatric airway, the EGD probe may increase the intracuff pressure (IP) of an airway device. The current study evaluated IP changes during EGD examination under general anesthesia in pediatric patients. Following the induction of anesthesia, a laryngeal mask airway (LMA) or endotracheal tube (ETT) was placed without neuromuscular blockade. The IP was measured at baseline, during EGD probe insertion, while the EGD probe was in place, and after probe removal. The study cohort included 101 patients (mean age 11.3 years). The airway was secured with an LMA and an ETT in 88 and 13 patients, respectively. The IP increased from 27 ± 15 cmH₂O at baseline to 34 ± 17 cmH₂O during probe insertion (p < 0.001), remained at 33 ± 16 cmH₂O while the probe was in place, and decreased to 26 ± 14 cmH₂O after probe removal. The IP of the LMA or ETT increased during EGD probe insertion and remained elevated while the probe was in place. High IP may compromise mucosal perfusion resulting in a sore throat when using an LMA or the potential for airway damage if an ETT is used. Removal of air from the cuff and titration of the IP should be considered after EGD insertion.

Digital palpation of the pilot balloon vs. continuous manometry for controlling the intracuff pressure in laryngeal mask airways

This study compared two methods of controlling the intracuff pressure in laryngeal mask airways. One hundred and eighty patients were randomly assigned into two groups. In the first group (n = 90), after training, the intracuff pressure was controlled using digital palpation of the pilot balloon. In the second group (n = 90), continuous manometry was used to control the intracuff pressure. An upper pressure limit of 60 cmH2 O was set. The median (IQR [range]) intracuff pressure in the palpation group was 130 (125-130 [120-130]) cmH2 O compared with 29 (20-39 [5-60]) cmH2 O in the manometry group (p < 0.001). In the palpation group, 37% of patients experienced pharyngolaryngeal complications vs. 12% in the manometry group (p < 0.001). We conclude that the digital palpation technique is not a suitable alternative to manometry in controlling the intracuff pressure in laryngeal mask airways.

Airway Complications during and after General Anesthesia: A Comparison, Systematic Review and Meta-Analysis of Using Flexible Laryngeal Mask Airways and Endotracheal Tubes

OBJECTIVE

Flexible laryngeal mask airways (FLMAs) have been widely used in thyroidectomy as well as cleft palate, nasal, upper chest, head and neck oncoplastic surgeries. This systematic review aims to compare the incidence of airway complications that occur during and after general anesthesia when using the FLMA and endotracheal intubation (ETT). We performed a quantitative meta-analysis of the results of randomized trials.

METHODS

A comprehensive search of the PubMed, Embase and Cochrane Library databases was conducted using the key words "flexible laryngeal mask airway" and "endotracheal intubation". Only prospective randomized controlled trials (RCTs) that compared the FLMA and ETT were included. The relative risks (RRs) and the corresponding 95% confidence intervals (95% CIs) were calculated using a quality effects model in MetaXL 1.3 software to analyze the outcome data.

RESULTS

Ten RCTs were included in this meta-analysis. There were no significant differences between the FLMA and ETT groups in the incidence of difficulty in positioning the airway [RR = 1.75, 95% CI = (0.70-4.40)]; the occurrence of sore throat at one hour and 24 hours postoperative [RR = 0.90, 95% CI = (0.13-6.18) and RR = 0.95, 95% CI = (0.81-1.13), respectively]; laryngospasms [RR = 0.58, 95% CI = (0.27-1.23)]; airway displacement [RR = 2.88, 95% CI = (0.58-14.33)]; aspiration [RR = 0.76, 95% CI = (0.06-8.88)]; or laryngotracheal soiling [RR = 0.34, 95% CI = (0.10-1.06)]. Patients treated with the FLMA had a lower incidence of hoarseness [RR = 0.31, 95% CI = (0.15-0.62)]; coughing [RR = 0.28, 95% CI = (0.15-0.51)] during recovery in the postanesthesia care unit (PACU); and oxygen desaturation [RR = 0.43, 95% CI = (0.26-0.72)] than did patients treated with ETT. However, the incidence of partial upper airway obstruction in FLMA patients was significantly greater than it was for ETT patients [RR = 4.01, 95% CI = (1.44-11.18)].

CONCLUSION

This systematic review showed that the FLMA has some advantages over ETT because it results in a lower incidence of hoarseness, coughing and oxygen desaturation. There were no statistically significant differences in the difficulty of intubation or in the occurrence of laryngospasms, postoperative sore throat, airway displacement, aspiration or laryngotracheal soiling. However, there was a higher incidence of partial upper airway obstruction in the FLMA than in the ETT group. We conclude that the FLMA has some advantages over ETT, but surgeons and anesthesiologists should be cautious when applying the mouth gag, moving the head and neck, or performing oropharyngeal procedures to avoid partial upper airway obstruction and airway displacement. The FLMA should not be used on patients at high risk for aspiration.

Application of Minimum Effective Cuff Inflating Volume for Laryngeal Mask Airway and its Impact on Postoperative Pharyngeal Complications

BACKGROUND

High intracuff pressure can cause severe pharyngeal complications including sore throat or hoarseness after laryngeal mask airway (LMA) removal postoperatively. Though the application of minimum effective cuff inflating volume is suggested to maintain airway sealing and adequacy of ventilation for patients receiving general anesthesia with LMA at lower level of the intracuff pressure, it is currently not a standard care in most of the anesthetic departments. In this study, the minimum effective cuff inflating volume was determined for classic LMA Well Lead™ (Well Lead Medical Co., Ltd., China) and its impact on postoperative pharyngeal complications was also explored.

METHODS

Patients with American Society of Anesthesiologists physical status (I-III) undergoing the short-duration urological surgery were recruited in this trial. First, the minimum effective cuff inflating volume was determined for size 4 or 5 LMA Well Lead in the study 1. Immediately following placement and confirmation of ideal LMA position, the cuff was inflated with 5, 7, 10 ml of air and up to 30 ml at 5 ml increment. The intracuff pressure, oropharyngeal leak pressure (OLP), and inspiratory peak airway pressure under positive pressure ventilation at the corresponding cuff volume as indicated above were recorded. Second, the enrolled patients were randomly allocated into minimum effective cuff inflating volume group (MC) and routine care (RC) group in the study 2. The minimum effective cuff inflating volume was applied and maintained in MC group, whereas the cuff volume was inflated with half of the maximum cuff inflating volume recommended by manufacturer in RC group throughout the surgical procedure and stay in postanesthesia care unit prior to LMA removal. The incidence of pharyngeal complications at 0, 2, 24, and 48 h after removal of LMA and other intra-operative adverse events were also documented.

RESULTS

The intracuff pressure varied with the cuff inflating volume in a positive linear correlation manner (Y = 11.68X - 42.1, r(2) = 0.9191) under the range of 5-30 ml for size 4 LMA. In similar with size 4 LMA, the data were also showed the linear relationship between the intracuff pressure and the cuff inflating volume (Y = 7.39X - 10.9, r(2) = 0.8855) for size 5 LMA. The minimal effective cuff inflating volume for size 4 or 5 LMA was 7-9 ml in combination of considering OLP needed to maintain airway sealing during intermittently positive pressure ventilation. The intracuff pressure in MC group was lower compared with RC group (63.0 ± 3.7 vs. 126.4 ± 24.0 cmH2O for size 4 LMA; 55.6 ± 2.4 vs. 138.5± 26.8 cmH2O for size 5 LMA; P < 0.0001). The incidence of pharyngeal adverse events was lower in MC group versus the RC group at 2, 24 h after LMA removal.

CONCLUSIONS

The relationship between the cuff inflating volume and the intracuff pressure for size 4 or 5 LMA Well Lead(TM) is in a linear correlation manner at the range of 5-30 ml. The minimal cuff inflating volume is adequate for satisfactory airway sealing and consequently associated with lower incidence of postoperative pharyngeal complications for LMA Well Lead.™.

[Continuous cuff pressure measurement during laryngeal mask anesthesia : An obligatory measure to avoid postoperative complications]

BACKGROUND

Inflation of laryngeal masks is often performed only with regard to the clinical impression and without any objective measurement of cuff pressure. As a result the use of laryngeal masks frequently leads to postoperative complications, such as sore throat, dysphonia, dysphagia and nerve palsy. In this study the influence of continuous measurement of cuff pressure on the incidence of postoperative sore throat was investigated in patients who underwent laryngeal mask anesthesia.

PATIENTS/MATERIAL AND METHODS

In the context of a retrospective audit all patients who underwent laryngeal mask anesthesia were asked to complete a questionnaire on anesthesia. The primary endpoint of the study was the postoperative occurrence of a sore throat. For analysis the patients were divided into two groups. In the first group the cuff pressure was controlled only by clinical means and in the second group the cuff pressure was controlled using continuous manometry. The study covered a 10-month period of observation for each group.

RESULTS

During the observation period laryngeal mask anesthesia was performed in 4169 patients. Of these 917 patients (manometry group n = 433 and control group n = 484) voluntarily completed the questionnaire. In the group without cuff pressure measurement 36 % of patients complained of sore throat postoperatively but only 12 % of the patients in the group with cuff pressure measurement (p < 0.001). Postoperative nausea and vomiting occurred in 16 % of the patients and 13 % complained of severe pain in the area of the operation. No differences between the two groups were found. While 97 % of patients in the group with continuous measurement of cuff pressure were satisfied with the anesthesia, this applied to only 79 % of patients in the control group (p = 0.006).

CONCLUSION

In terms of the results of this study and with respect to data from the literature, measurement of cuff pressure should be compulsory during laryngeal mask anesthesia.

Reducing sore throat following laryngeal mask airway insertion: comparing lidocaine gel, saline, and washing mouth with the control group

BACKGROUND

Laryngeal mask airway is still accompanied by complications such as sore throat. In this study, effects of three methods of reducing postoperative sore throat were compared with the control group.

METHODS

240 patients with ASA I, II candidates for cataract surgery were randomly divided into four same groups. No supplementary method was used in the control group. In the second, third and fourth groups, lidocaine gel, washing cuff before insertion, and washing mouth before removing laryngeal mask airway were applied, respectively. Anesthesia induction was done with fentanyl, atracurium, and propofol and maintained with propofol infusion. The incidence of sore throat was evaluated during the recovery, 3-4h later and after 24h using verbal analog scale. The data were analyzed by t-test, analysis of variance and chi-square using SPSS V11.5.

RESULTS

Age, gender, duration of surgery and cuff pressure were the same in all the four groups. Incidence of sore throat at recovery room was highest in the control group (43.3%) and lowest in the washing mouth group (25%). However, no significant statistical difference was observed between these four groups (recovery, p=0.30; discharge, p=0.31; examination, p=0.52). In this study, increased duration of operation had a significant relationship with the incidence of sore throat (p=0.041).

CONCLUSION

Sore throat is a common postoperative problem, but no special method has been found completely efficient yet. In this study, cuff washing, lidocaine gel, and mouth washing before removing laryngeal mask airway were not helpful for sore throat.

Comparisons of clinical performance of Guardian laryngeal mask with laryngeal mask airway ProSeal

Background

The Guardian Laryngeal Mask Airway (G-LMA) is a new silicone-based single-use extraglottic device with the drainage port and a cuff pilot valve with pressure indicator. The aim of this study is to compare the clinical performance of this laryngeal mask airway with ProSeal laryngeal mask airway (P-LMA).

Methods

In this prospective randomized study, we included adult patients with ASA grading I and II scheduled for elective surgery requiring supine position under total intravenous anesthesia. The patients were randomly allocated to two groups, 40 in each. G-LMA and P-LMA were used in groups G and P respectively. The cuff of each device was air inflated to 60 cmH₂O. The primary outcome was to compare the airway sealing pressure and the secondary outcome was to compare the efficacy and safety of these two devices with respect to insertion success, insertion time, ease of insertion, volume of air for cuff inflation to 60 cmH₂O, intracuff pressure measurement, gastric tube insertion attempt, gastric tube insertion time, Fiberoptic laryngeal view, and postoperative pharyngolaryngeal morbidity.

Results

The airway sealing pressure at 60cmH₂O cuff pressure was significantly greater in G-LMA than P-LMA (p = 0.04).The first successful attempt of both groups were comparable (p = 1.000). Insertion time was significantly shorter in G-LMA than P-LMA (p < 0.0001). The first successful attempt for the gastric tube insertion in both groups was comparable (p = 0.431). Gastric tube insertion time was less in G-LMA than in P-LMA (p < 0.0001). The volume of air for cuff inflation to 60 cmH₂O was more in G-LMA than in P-LMA (<0.0001). The intracuff pressure measurement at 30, 60, 90 and 120 minutes were comparable (p = 0.823, 0.182, 0.870, 0.658).We did not find differences in ease of insertion (p = 0.60); Fiber-optic positions of airway devices were comparable (p = 0.83). In addition, blood staining (p = 1.00), sore throat and dysphagia at 1, 2 and 24 hour (p = 1.00) were comparable in both groups.

Conclusion

The Guardian laryngeal mask airway was associated with high airway sealing pressure with a quicker insertion of the device as well as gastric tube.

Trial registration

Clinical Trial.gov Identifier: NCT02063516. Date: June 2013

Electronic supplementary material

The online version of this article (doi:10.1186/s12871-015-0039-3) contains supplementary material, which is available to authorized users.

Comparison of three methods for the confirmation of laryngeal mask airway placement in female patients undergoing gynecologic surgery

The laryngeal mask airway (LMA) is a supraglottic device that is commonly used to provide lung ventilation during general anesthesia. LMA placement needs to be confirmed to provide adequate lung ventilation. To investigate the feasibility of using ultrasound examination, compared with clinical tests and fiberoptic laryngoscopy, to confirm LMA placement, we performed a clinical study of 64 female patients classified as American Society of Anesthesiologists Physical Status I or II who were scheduled for gynecologic surgery with LMA insertion for airway management. After insertion, placement of the LMA was confirmed by clinical tests, ultrasound examination and fiberoptic laryngoscopy. Of the 64 women, placement was confirmed as acceptable in 89.1% by clinical tests, in 59.4% by fiberoptic laryngoscope assessment and in 67.2% by ultrasound examination. With respect to patients with oropharyngeal leaks classified as high, there were no differences in confirmation of acceptable placement between clinical tests and ultrasound examinations (p = 0.092), but the number of patients determined to have acceptable placement by ultrasound examination was greater than that determined by fiberoptic laryngoscopy (p = 0.034). Thus, ultrasound examination is a superior technique for confirming the seal on the LMA.

Improving patient safety after rigid bronchoscopy in adults: laryngeal mask airway versus face mask - a pilot study

Background

There are still no clear guidelines in the literature on per procedural bronchoscopic management for anesthesiologists, and few relevant datasets are available. To obtain rapid recovery from anesthesia, it is often necessary to keep patients in the recovery room for several hours until they become clinically stable. In this study, we tested the hypothesis that the laryngeal mask airway (LMA) enables better respiratory and hemodynamic recovery than the oxygen face mask (FM) in patients undergoing rigid bronchoscopy.

Methods

Twenty-one patients undergoing elective bronchoscopy of the upper airway were randomized to ventilation assistance with FM or LMA after a rigid bronchoscopy procedure under general anesthesia. The primary endpoint was duration of post-surgical recovery and the secondary endpoints were postoperative hemodynamic and respiratory parameters. Assessment of the study endpoints was performed by an intensive care specialist blinded to the method of ventilation used. The statistical analysis was performed using the Fisher’s Exact test for nominal data and the Student’s t-test for continuous data.

Results

There was no statistically significant difference in post-procedural time between the two groups (P=0.972). The recovery parameters were significantly better in the LMA group than in the FM group, with significantly fewer desaturation, hypotensive, and bradycardic events (P<0.05).

Conclusion

We conclude that the LMA may be safer and more comfortable than the FM in patients undergoing rigid bronchoscopy.

Comparison of i-gel™ and laryngeal mask airway in anesthetized paralyzed patients

BACKGROUND

The i-gel™ is a new device introduced recently. It differs from other supraglottic airway devices. It has a non-inflatable, gel-made cuff. Previously used devices, have some disadvantages which are claimed to be absent in i-gel™. In this study we aimed to compare the performance of the laryngeal mask airway (LMA)-Classic™ and i-gel™ during anesthesia in paralyzed patients.

MATERIALS AND METHODS

A total of 64 anaesthetized patients with paralysis were enrolled in a single-blind, randomized control trial to be intubated with one of the devices. We compared the device insertion parameters, some ventilatory parameters, and adverse effects after device insertion.

RESULTS

Vital signs were not significantly different between groups. Regarding duration of insertion attempts, the difference between groups was significant (P < 0.05); while the number of insertion attempts was insignificant (P = 0.265). There was no significant difference between both groups regarding postoperative complications (cough, sore throat, and blood on the cuff) (P > 0.05). Airway leak was assessed in both groups and data showed no significant difference (P = 0.662). Additionally, end-tidal CO2 change regarding the baseline value was significantly different after 10 and 15 min of anesthesia (P < 0.05).

CONCLUSIONS

Successful insertion time was shorter significantly for i-gel™. As i-gel™ has easy application, it is advantageous to be used during cardiopulmonary resuscitation by non-anesthetists in which time is very important. We concluded that i-gel™ can be an alternative to LMA-Classic™ for controlled ventilation during anesthesia as it is easier to be placed.

Gender differences in sore throat and hoarseness following endotracheal tube or laryngeal mask airway: a prospective study

Background

Postoperative sore throat and hoarseness are common minor complications following airway manipulation. This study was primarily done to determine gender differences in the incidence of these symptoms and the location of POST after laryngeal mask airway (LMA) and endotracheal tube (ETT).

Methods

A total of 112 men and 185 women were included during a four month period. All patients were evaluated postoperatively and after 24 hours about the occurrence of sore throat, its location and hoarseness. If the patients had any symptom, they were followed-up at 48, 72 and 96 hours until the symptoms resolved.

Results

There was no significant gender difference in postoperative sore throat (POST) and postoperative hoarseness (PH) when analyzing both airway devices together. The incidence of sore throat and hoarseness were higher postoperatively after an ETT than an LMA (32% vs. 19%, p = 0.012) and 57% vs. 33% (p < 0.001) respectively. Significantly more women than men had POST after an LMA (26% vs. 6%, p = 0.004). No significant gender difference was found in either POST or PH after an ETT or in the incidence of PH after an LMA. More patients located their pain below the larynx after an ETT vs. an LMA (24% vs. 4%). Pain above the larynx was more common after an LMA than an ETT (52% vs. 37%).

Conclusions

In a clinical setting where women are intubated with a smaller size ETT than men, there were no significant differences in POST or PH between genders. Additionally, more women than men have POST when an LMA is used. Awareness of POST and PH may help streamline patients in whom the best airway device could be used during anesthesia and surgery.

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.

New supraglottic airway with built-in pressure indicator decreases postoperative pharyngolaryngeal symptoms: a randomized controlled trial

PURPOSE

Excessive supraglottic airway cuff pressure increases postoperative pharyngolaryngeal symptoms such as sore throat, dysphonia, and dysphagia. A new supraglottic airway, AES Ultra CPV™ (CPV), has a built-in intracuff pressure indicator. We hypothesized that using the CPV would reduce postoperative symptoms when compared with the LMA Classic™ (LMA) without intracuff pressure guidance.

METHODS

Ambulatory patients undergoing general anesthesia were randomized to either CPV or LMA. A size 3/4/5 was inserted according to manufacturer guidelines. Nitrous oxide was not used. In the LMA Group, the cuff was inflated according to manufacturer's guidelines. In the CPV Group, a CPV was inserted and the cuff inflated until the indicator was in the green zone (30-44 mmHg). Intracuff pressures were measured at five minutes and 20 min post-insertion in both groups. The primary outcome was the incidence of pharyngolaryngeal symptoms, defined as sore throat, dysphonia, and/or dysphagia at one, two, and/or 24 hr postoperatively. Continuous data were compared using Student's t test and categorical data were analyzed using Chi square analysis.

RESULTS

The study included 170 patients, 85 per group. The mean (SD) intracuff pressure in the CPV group was significantly lower [44 (4) mmHg] than in the LMA Group [87 (37) mmHg]; P < 0.001. The incidence of pharyngolaryngeal symptoms was significantly lower in the CPV Group than in the LMA Group (26% vs 49%; P = 0.002). The absolute risk reduction was 24%, and the number-needed-to-treat was 4.3.

CONCLUSION

The incidence of postoperative pharyngolaryngeal symptoms in the CPV Group with a cuff pressure-guided strategy was significantly lower than in the LMA Group with standard practice. (

CLINICAL TRIAL REGISTRATION NUMBER

NCT01800344).

Jaw-thrust induces sympathetic responses during induction of general anesthesia

Background

Jaw-thrust is a noxious stimulus that might induce sympathetic responses. The purpose of this study, was to evaluate the effects of jaw-thrust on sympathetic responses.

Methods

We investigated seventy three patients. Patients who received general anesthesia were randomly divided into a control group (maintenance of combined airway maneuver with head tilt, open mouth by mouthpiece, and chin-lift, n = 30) and jaw-thrust group (maintenance of head tilt, open mouth and jaw-thrust, n = 30). In the jaw-thrust group, four minutes of endoscopy-guided force to the mandible to get the best laryngeal view were applied. For the control group, the combined airway maneuver was maintained during the same period. Arterial blood pressure (AP) and heart rate (HR) were recorded at predetermined time points (1 min before anesthesia induction, 2 min after fiberoptic bronchoscopy placement, and thereafter 1 min-interval during each airway maneuver) during jaw-thrust and chin-lift maneuver. The force amplitude applied for best laryngeal view during jaw-thrust was also measured.

Results

Peak systolic and diastolic AP increased 39.0 ± 17.6 and 39.9 ± 22.8 mmHg from the baseline (P < 0.001) in the jaw-thrust group. HR was also 32.5 ± 19.4 beats/min from the baseline (P < 0.001) in the jaw-thrust group. These remained high at all time points, compared with the control group (P < 0.01). The force magnitude applied for jaw-thrust was not correlated to the AP and HR changes (P > 0.05).

Conclusions

Performing the jaw-thrust maneuver induces significant sympathetic responses, irrespective of the force magnitude.

Comparison of clinical performance of the I-gel with LMA proseal

Aim:

To compare insertion characteristics of 2 different supraglottic devices [I-gel and Proseal laryngeal mask airway (PLMA)] and to observe any associated complications.

Study Design:

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.

Statistical Analysis:

Student t-test and Mann-Whitney test were employed to compare the means; for categorical variables, Chi-square test was used.

Result:

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.

Effect of Intravenous Hydrocortisone on Preventing Postoperative Sore Throat Followed by Laryngeal Mask Airway Use in patients Undergoing Urogenital Surgeries

INTRODUCTION

Postoperative sore throat is a common complication which can lead to discomfort after operation and delay in patients' returning to normal daily activities. The present study was carried out to evaluate the influence of intravenous hydrocortisone on preventing postoperative sore throat followed by laryngeal mask airway use.

METHODS

Sixty patients who were scheduled to undergo urogenital surgery were divided into two groups. Five minutes before anesthesia induction, 100 mg of intravenous hydrocortisone or placebo with the same volume were given to the patients randomly. At the end of the operation and after LMAs were removed, patients were asked about having sore throat at hours 2, 4 and 24 after operation.

RESULTS

There were three and six cases of sore throat after operation in hydrocortisone and in placebo groups respectively which showed no significant statistical difference (P=0.472). No cases of moderate or severe pain were reported in any of the patients in both groups and no statistically significant difference was observed regarding pain severity in recovery, hours 2, 4 or 24 after operation.

CONCLUSION

Based on the statistical data obtained from this research, administrating intravenous hydrocortisone five minutes before anesthesia induction has no effect on postoperative sore throat severity and degree in urogenital surgeries.