Unanticipated difficult airway after prolonged use of a laryngeal mask airway

The laryngeal mask airway (LMA) is recognized as a safe alternative to endotracheal intubation for short-term airway maintenance. In this case report we present the case of a term neonate with upper airway obstruction which was managed with a deflated LMA for 7 consecutive days. Despite previous reports of extended LMA use in neonates without complications, this patient experienced significant pharyngeal mucosal injury and edema, leading to difficulty with subsequent intubation attempts.

Laryngeal mask airway surfactant administration for prevention of morbidity and mortality in preterm infants with or at risk of respiratory distress syndrome

BACKGROUND

Laryngeal mask airway surfactant administration (S-LMA) has the potential benefit of surfactant administration whilst avoiding endotracheal intubation and ventilation, ventilator-induced lung injury and bronchopulmonary dysplasia (BPD).

OBJECTIVES

To evaluate the benefits and harms of S-LMA either as prophylaxis or treatment (rescue) compared to placebo, no treatment, or intratracheal surfactant administration via an endotracheal tube (ETT) with the intent to rapidly extubate (InSurE) or extubate at standard criteria (S-ETT) or via other less-invasive surfactant administration (LISA) methods on morbidity and mortality in preterm infants with or at risk of respiratory distress syndrome (RDS).

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, CINAHL, and three trial registries in December 2022.

SELECTION CRITERIA

Randomised controlled trials (RCTs), cluster- or quasi-RCTs of S-LMA compared to placebo, no treatment, or other routes of administration (nebulised, pharyngeal instillation of surfactant before the first breath, thin endotracheal catheter surfactant administration or intratracheal surfactant instillation) on morbidity and mortality in preterm infants at risk of RDS. We considered published, unpublished and ongoing trials.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed studies for inclusion and extracted data. We used GRADE to assess the certainty of the evidence.

MAIN RESULTS

We included eight trials (seven new to this update) recruiting 510 newborns. Five trials (333 infants) compared S-LMA with surfactant administration via ETT with InSurE. One trial (48 infants) compared S-LMA with surfactant administration via ETT with S-ETT, and two trials (129 infants) compared S-LMA with no surfactant administration. We found no studies comparing S-LMA with LISA techniques or prophylactic or early S-LMA. S-LMA versus surfactant administration via InSurE S-LMA may have little or no effect on the composite outcome of death or BPD at 36 weeks' postmenstrual age (risk ratio (RR) 1.50, 95% confidence interval (CI) 0.27 to 8.34, I 2 = not applicable (NA) as 1 study had 0 events; risk difference (RD) 0.02, 95% CI -0.07 to 0.10; I 2 = 0%; 2 studies, 110 infants; low-certainty evidence). There may be a reduction in the need for mechanical ventilation at any time (RR 0.53, 95% CI 0.36 to 0.78; I 2 = 27%; RD -0.14, 95% CI -0.22 to -0.06, I 2 = 89%; number needed to treat for an additional beneficial outcome (NNTB) 7, 95% CI 5 to 17; 5 studies, 333 infants; low-certainty evidence). However, this was limited to four studies (236 infants) using analgesia or sedation for the InSurE group. There was little or no difference for air leak during first hospitalisation (RR 1.39, 95% CI 0.65 to 2.98; I 2 = 0%; 5 studies, 333 infants (based on 3 studies as 2 studies had 0 events); low-certainty evidence); BPD among survivors to 36 weeks' PMA (RR 1.28, 95% CI 0.47 to 3.52; I 2 = 0%; 4 studies, 264 infants (based on 3 studies as 1 study had 0 events); low-certainty evidence); or death (all causes) during the first hospitalisation (RR 0.28, 95% CI 0.01 to 6.60; I 2 = NA as 2 studies had 0 events; 3 studies, 203 infants; low-certainty evidence). Neurosensory disability was not reported. Intraventricular haemorrhage ( IVH) grades III and IV were reported among the study groups (1 study, 50 infants). S-LMA versus surfactant administration via S-ETT No study reported death or BPD at 36 weeks' PMA. S-LMA may reduce the use of mechanical ventilation at any time compared with S-ETT (RR 0.47, 95% CI 0.31 to 0.71; RD -0.54, 95% CI -0.74 to -0.34; NNTB 2, 95% CI 2 to 3; 1 study, 48 infants; low-certainty evidence). We are very uncertain whether S-LMA compared with S-ETT reduces air leak during first hospitalisation (RR 2.56, 95% CI 0.11 to 59.75), IVH grade III or IV (RR 2.56, 95% CI 0.11 to 59.75) and death (all causes) during the first hospitalisation (RR 0.17, 95% CI 0.01 to 3.37) (1 study, 48 infants; very low-certainty evidence). No study reported BPD to 36 weeks' PMA or neurosensory disability. S-LMA versus no surfactant administration Rescue surfactant could be used in both groups. There may be little or no difference in death or BPD at 36 weeks (RR 1.65, 95% CI 0.85 to 3.22; I 2 = 58%; RD 0.08, 95% CI -0.03 to 0.19; I 2 = 0%; 2 studies, 129 infants; low-certainty evidence). There was probably a reduction in the need for mechanical ventilation at any time with S-LMA compared with nasal continuous positive airway pressure without surfactant (RR 0.57, 95% CI 0.38 to 0.85; I 2 = 0%; RD -0.24, 95% CI -0.40 to -0.08; I 2 = 0%; NNTB 4, 95% CI 3 to 13; 2 studies, 129 infants; moderate-certainty evidence). There was little or no difference in air leak during first hospitalisation (RR 0.65, 95% CI 0.23 to 1.88; I 2 = 0%; 2 studies, 129 infants; low-certainty evidence) or BPD to 36 weeks' PMA (RR 1.65, 95% CI 0.85 to 3.22; I 2 = 58%; 2 studies, 129 infants; low-certainty evidence). There were no events in either group for death during the first hospitalisation (1 study, 103 infants) or IVH grade III and IV (1 study, 103 infants). No study reported neurosensory disability.

AUTHORS' CONCLUSIONS

In preterm infants less than 36 weeks' PMA, rescue S-LMA may have little or no effect on the composite outcome of death or BPD at 36 weeks' PMA. However, it may reduce the need for mechanical ventilation at any time. This benefit is limited to trials reporting the use of analgesia or sedation in the InSurE and S-ETT groups. There is low- to very-low certainty evidence for no or little difference in neonatal morbidities and mortality. Long-term outcomes are largely unreported. In preterm infants less than 32 weeks' PMA or less than 1500 g, there are insufficient data to support or refute the use of S-LMA in clinical practice. Adequately powered trials are required to determine the effect of S-LMA for prevention or early treatment of RDS in extremely preterm infants. S-LMA use should be limited to clinical trials in this group of infants.

2023 American Heart Association and American Academy of Pediatrics Focused Update on Neonatal Resuscitation: An Update to the American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care

This 2023 focused update to the neonatal resuscitation guidelines is based on 4 systematic reviews recently completed under the direction of the International Liaison Committee on Resuscitation Neonatal Life Support Task Force. Systematic reviewers and content experts from this task force performed comprehensive reviews of the scientific literature on umbilical cord management in preterm, late preterm, and term newborn infants, and the optimal devices and interfaces used for administering positive-pressure ventilation during resuscitation of newborn infants. These recommendations provide new guidance on the use of intact umbilical cord milking, device selection for administering positive-pressure ventilation, and an additional primary interface for administering positive-pressure ventilation.

Comparison of lidocaine viscous gargle and topical application on laryngeal mask airway in general anesthesia: A randomized clinical trial

OBJECTIVES

To investigate the effects and safety of lidocaine viscous gargle on postoperative sore throat (POST) in patients receiving a laryngeal mask airway (LMA) in general anesthesia.

METHODS

In this randomized controlled trial, 90 patients undergoing urological surgery were allocated into 2 treatment arms (n=45): lidocaine viscous gargle before LMA insertion (Group G) and topical application of lidocaine viscous on the LMA (Group T). Outcome data were collected before placement of LMA (T0), after insertion of LMA (T1), immediately (T2), one hour (T3), and 24 hours after removal of LMA (T4). We analyzed the incidence of POST, pharynx dryness, and adverse events.

RESULTS

The incidence of POST was lower in Group G than Group T at T2 (11.1% vs. 28.9%; p=0.063), T3 (11.1% vs. 24.4%; p=0.167), and T4 (2.2% vs. 4.4%; p=0.566), but there was no significant difference between groups. No patient in either group experienced severe pain or treatment-related adverse events. There was a significantly lower incidence of pharynx dryness in Group G than Group T (p<0.05) at T2, T3, and T4.

CONCLUSION

Lidocaine viscous gargle showed no statistically significant difference in incidence of POST and incidence of pharynx dryness compared with topical application of lidocaine on the LMA. Both approaches were safe for patients receiving LMA.Chinese Clinical Trial Register No.: ChiCTR2200059720.

Exchange of a Tracheal Tube and Supraglottic Airway Device: Evaluation of Different Techniques in Three Simulated Airway Scenarios (TUBE Study)-A Prospective, Randomised Controlled Study

BACKGROUND

The swapping of a supraglottic airway device or a tracheal tube in anaesthetised adult patients is a challenging procedure because potential complications through hypoxemia and loss of airway may occur, with life-threatening implications. This study aims to evaluate which airway technique offers the highest success rate concerning a secure airway in established supraglottic airway and tracheal tube airway exchange scenarios.

METHODS

After ethical approval, anaesthesiologists were randomised 1:1 into simulated scenarios: an LTS group (malpositioned laryngeal tube) and a Cuff group (relevant cuff leakage of a placed tracheal tube). After that, both groups completed a common scenario consisting of a partially obstructed tracheal tube lumen in a fixed prone position with a Mayfield clamp. The primary endpoint was a successful tracheal airway exchange within ten minutes after the start of the scenario and before severe hypoxemia (SpO2 < 80%) arose. Secondary endpoints were the evaluation of factors influencing success after 10 min.

RESULTS

In total, 60 anaesthesiologists (LTS group n = 30; Cuff group n = 30) with a median experience of 7 years (IQR 4-11) were observed. Within 10 min, a malpositioned laryngeal tube was successfully exchanged by 27/30 (90%) participants, compared to the exchange of a tracheal tube with a relevant cuff leakage by 29/30 (97%; p > 0.05). An airway exchange in an obstructed tube scenario occurred in 22/59 (37%). Loss of airway maintenance showed an obvious association with failure in the common scenario (p = 0.02).

CONCLUSION

The results of this simulation-based study reflect that the exchange of an existing but insufficient airway device in clinical practice is a high-risk procedure. Especially in a fixed prone position, the deliberate evaluation of the existing airway patency and well-conceived airway management in the case of the accidental loss of the airway or obstructed airway access are crucial.

Comparison of clinical performance of Baska mask and Ambu AuraGain in patients undergoing surgery: A single-blinded, randomised comparative trial

Background and Aims

The Baska mask (BM) and the Ambu AuraGain (AAG) have shown promising results in recent trials but have not been compared. Therefore, we aimed to compare the clinical performance of the BM and the AAG for airway management of adult patients.

Methods

In this randomised comparative study, patients aged 18-60 years and with an expected surgical duration of less than 2 h were enroled. Patients were randomly allocated to AAG (Group A, n = 37) and BM (Group B, n = 37) for airway management. After induction of anaesthesia, an allocated supraglottic airway device (SAD) was inserted. Oropharyngeal leak pressure (OLP), time taken to insert SAD, number of insertion attempts, leak fraction (LF), first-attempt success rate, overall success rate, ease of insertion, fiberoptic view of the glottis, and complications were compared. The data were analysed using Student's t-test, Mann-Whitney U test, and Fisher's exact tests.

Results

Baseline and demographic characteristics were comparable. OLP (31.32 ± 2.59 versus 27.54 ± 1.32 cmH2O) was higher (P < 0.001), and LF (6.19% ± 1.20% versus 7.24% ± 1.72%) was lower (P = 0.003) in the BM group. First-attempt and overall success rate, time taken to insert, number of insertion attempts, ease of insertion, and fibreoptic view of glottis through the SADs were statistically similar between groups. However, the incidence of sore throat (P = 0.007) and cough (P = 0.028) was higher with AAG.

Conclusion

Clinical performance of BM was better than AAG as the former had higher OLP, lower LF and complications.

Comparison of gum elastic bougie-guided insertion of LMA ProtectorTM versus the conventional method in achieving oesophagal patency - A randomised comparative study

Background and Aims

The passage of a Ryle's tube through the drain port on the laryngeal mask airway (LMA) ProtectorTM has been reported to be arduous despite the larger gastric channel. There are no studies on the evaluation of the guided insertion of LMA ProtectorTM to achieve adequate gastrointestinal drainage function.

Methods

This randomised study included 132 patients who underwent surgery under general anaesthesia. The gum elastic bougie (GEB)-guided insertion of LMA ProtectorTM (group I) was compared with the conventional method (group II), and the alignment of the tip of the drain tube with the oesophagus was assessed. The insertion characteristics of the device, accuracy of LMA ProtectorTM placement, haemodynamic parameters, and post-operative airway morbidity following the insertion of the device were also compared between the two groups.

Results

The first-attempt success rate for the placement of LMA ProtectorTM and the patency of oesophagus was higher in group I patients than in group II (100% vs 84.8%; P < 0.001). However, the time taken for device insertion and associated haemodynamic changes were significantly longer in group I. The patients in group I had better visualisation of laryngeal structures. The GEB-assisted insertion of LMA ProtectorTM resulted in less incidence of blood staining at the cuff of the device.

Conclusion

GEB-guided insertion of LMA ProtectorTM achieved better oesophageal patency than the conventional insertion method. This method also had higher first-attempt success at the placement of the device and was observed to be less traumatic.

Clinical utility of i-gel® and BlockBuster™ supraglottic devices for airway management in postburn injury contracture neck patients under general anesthesia: A randomized controlled trial

Background

Post burn injury contracture (PBC) neck patients pose a unique challenge for the anesthesiologists. The use of supraglottic device (SGDs) for managing such patients is being increasingly used. We compared i-gel® and LMA BlockBuster™ in PBC adult patients under general anesthesia (GA).

Methods

The study included 63 subjects with mild/moderate PBC neck of either sex with American Society of Anesthesiologists Physical Status I and II under GA. Patients with intraoral pathology, mouth opening <2.5 cm, and severe contracture were excluded. Patients were randomly assigned to i-gel® (I) and BlockBuster™ (B) groups. The primary objective of the study was the time for successful insertion. First attempt success rate, oropharyngeal leak pressures (OLP), and complications were also assessed.

Results

Mean insertion time was significantly less in Group I as compared to Group B (17.35 ± 1.43 vs. 21.32 ± 1.10 s; P < 0.001), OLP in Group B was significantly higher as compared to Group I (34.03 ± 1.33 vs. 25.23 ± 3.04 cm of H2O; P < 0.001). Group I was found to be statistically easier to insert as compared to Group B (P = 0.011) with reduced requirement of airway maneuvering to insert the device (P = 0.017). Groups were similar in terms of complications.

Conclusion

SGDs are attractive option for airway management in mild/moderate degree of PBC neck. i-gel® having shorter insertion time with easier insertion can be favorable at times of emergency while use of LMA BlockBuster™ can be preferred to reduce the risk of aspiration owing to higher OLP.

A randomized controlled trial comparing three supraglottic airway devices used as a conduit to facilitate tracheal intubation with flexible bronchoscopy

PURPOSE

Once difficult ventilation and intubation are declared, guidelines suggest the use of a supraglottic airway (SGA) as a rescue device to ventilate and, if oxygenation is restored, subsequently as an intubation conduit. Nevertheless, few trials have formally studied recent SGA devices in patients. Our objective was to compare the efficacy of three second-generation SGA devices as conduits for bronchoscopy-guided endotracheal intubation.

METHODS

In this prospective, single-blinded three-arm randomized controlled trial, patients with an American Society of Anesthesiologists Physical Status of I-III undergoing general anesthesia were randomized to bronchoscopy-guided endotracheal intubation using AuraGain™, Air-Q® Blocker, or i-gel® devices. We excluded patients with contraindications to an SGA or drugs and who were pregnant or had a neck, spine, or respiratory anomaly. The primary outcome was intubation time, measured from SGA circuit disconnection to CO2 measurement. Secondary outcomes included ease, time, and success of SGA insertion; success of intubation on first attempt; overall intubation success; number of attempts to intubate; ease of intubation; and ease of SGA removals.

RESULTS

One hundred and fifty patients were enrolled from March 2017 to January 2018. Median intubation times were similar across the three groups (Air-Q Blocker, 44 sec; AuraGain, 45 sec; i-gel, 36 sec; P = 0.08). The i-gel was faster to insert (i-gel: 10 sec; Air-Q Blocker, 16 sec; AuraGain, 16 sec; P < 0.001) and easier to insert (Air-Q Blocker vs i-gel, P = 0.001; AuraGain vs i-gel, P = 0.002). Success of SGA insertion, success of intubation, and number of attempts were similar. The Air-Q Blocker was easier to remove than the i-gel (P < 0.001).

CONCLUSION

All three second-generation SGA devices performed similarly regarding intubation. Despite minor benefits of the i-gel, clinicians should select their SGA based on clinical experience.

STUDY REGISTRATION

ClinicalTrials.gov (NCT02975466); registered on 29 November 2016.

Effect of Intermediate Airway Management on Ventilation Parameters in Simulated Pediatric Out-of-Hospital Cardiac Arrest: Protocol for a Multicenter, Randomized, Crossover Trial

Most pediatric out-of-hospital cardiac arrests (OHCAs) are caused by hypoxia, which is generally consecutive to respiratory failure. To restore oxygenation, prehospital providers usually first use basic airway management techniques, i.e., bag-valve-mask (BVM) devices. These devices present several drawbacks, most of which could be avoided using supraglottic airway devices. These intermediate airway management (IAM) devices also present significant advantages over tracheal intubation: they are associated with higher success and lower complication rates in the prehospital setting. There are, however, few data regarding the effect of early IAM in pediatric OHCA. This paper details the protocol of a trial designed to evaluate the impact of this airway management strategy on ventilation parameters through a simulated, multicenter, randomized, crossover trial. The hypothesis underlying this study protocol is that early IAM without prior BVM ventilations could improve the ventilation parameters in comparison with the standard approach, which consists in BVM ventilations only.

What airway management information do anaesthetic charts prompt for? An audit of charts from 132 hospitals across Australia and New Zealand

Anaesthetists can make safer airway plans if they know which airway techniques worked previously and which ones did not. Anaesthetic charts do not always capture this information, however, and guidelines from the Australian and New Zealand College of Anaesthetists do not specify what details on airway management they should include. To assess how anaesthetic charts support airway documentation, we audited the airway management section of blank charts from 132 hospitals accredited for training by the Australian and New Zealand College of Anaesthetists. We evaluated charts for the presence of 17 clinically important data fields describing tracheal intubation, supraglottic airway use and bag-mask ventilation. Our audit revealed that data fields on anaesthetic charts focus more on tracheal intubation than bag-mask ventilation or supraglottic airway use. Nearly all charts (99%) had prompts for intubation and most had prompts for both operator technique and patient outcome. For supraglottic airway use, 95% of charts had at least one data field, but few had prompts for difficulty or outcome. For bag-mask ventilation, 58% of charts had a data field for difficulty but most of these were subjective; few (1.5%) included any outcome measures. Data fields describing bag-mask ventilation and supraglottic airway use were also inconsistent. In summary, data fields on Australian and New Zealand anaesthetic charts focus on tracheal intubation with consistent prompts for both operator method and outcome. The inclusion of fields for outcome and difficulty of bag-mask ventilation and supraglottic airway use could help clinicians make better records of airway management.

Learning curve of fiberoptic-guided tracheal intubation through supraglottic airway device for pediatric airway management: a manikin study

Background

Although fiberoptic-guided endotracheal intubation using a supraglottic airway device is a good alternative for the management of difficult airways, its learning curve for residents has not been evaluated in pediatric patients. We aimed to train residents using a pediatric manikin and obtain learning curves for the procedure to evaluate the efficiency of the training.

Methods

We conducted a single-armed prospective study with anesthesiology residents. Plain endotracheal tube intubation guided by a fiberoptic bronchoscope through Ambu® AuraGainTM was demonstrated in a pediatric manikin to the participants before training. The procedure was divided into four steps: supraglottic airway device insertion, vocal cord identification, carina identification, and endotracheal tube insertion into the trachea. The results and elapsed procedure times of each trial were recorded. The learning curves for the participants were constructed and analyzed using the cumulative sum method.

Results

All of the 30 participants acquired proficiency at the end of the practice between eight and 25 trials. The overall success rate for the procedure was 92.8%, and above 80% for all participants. Mean (±SD) procedure time was 71.3 (±50.7) s. The 4th step accounted for 86.2% of total failures and 48.0% of the total procedure time. The procedure time rapidly decreased in the 2nd trial, and a modest decline was observed thereafter.

Conclusions

Anesthesiology residents obtained proficiency within 25 times of practice for fiberoptic-guided intubation in a pediatric manikin through an AuraGain supraglottic airway device with acceptable success rate and procedure time. The procedure time markedly decreased following the first experience.

Comparative evaluation of airway dynamics in patients undergoing laparoscopic cholecystectomy under general anaesthesia with controlled ventilation using ProSeal laryngeal mask airway, I-Gel™ and Baska mask

Background and Aims

TheProSeal™ laryngeal mask airway (PLMA) and I-Gel™ are second-generation supraglottic airway devices (SADs). The Baska mask is a SAD having a non-inflatable cuff with a tendency to increase the perilaryngeal seal with an increase in airway pressures. This study compared the efficacy of I-Gel™, PLMA and Baska mask with respect to airway dynamics in patients scheduled for laparoscopic surgeries under general anaesthesia (GA).

Methods

Ninety patients, of American Society of Anesthesiologists physical status I and II, aged 20-65 years scheduled for laparoscopic cholecystectomy under GA were enroled. The patients were randomised into three groups: Group P (n = 30): airway secured using PLMA, Group I (n = 30): airway secured using I-Gel™ and Group B (n = 30): airway secured using Baska mask. The primary outcome was the change in dynamic compliance, and the secondary outcomes included insertion time, changes in peak inspiratory pressure (PIP) and oropharyngeal leak pressure (OLP) at different time intervals.

Results

After insertion of the SADs, the dynamic compliance was highest in group B and least in the group I (p = 0.01). The maximum decrease in dynamic compliance was observed in group I. The insertion time for SAD placement was more in group P. The group B had least PIP as compared to groups P, I at insertion. After carboperitonium, groups P and B had comparable PIP, and group I had highest PIP (p = 0.001). OLP was highest in group B, whereas group I had least OLP.

Conclusion

The airway dynamics are better maintained with Baska mask as compared to the PLMA and I-Gel™.

Laryngeal Masks in Neonatal Resuscitation-A Narrative Review of Updates 2022

Positive pressure ventilation (PPV) is crucial to neonatal cardiopulmonary resuscitation because respiratory failure precedes cardiac failure in newborns affected by perinatal asphyxia. Prolonged ineffective PPV could lead to a need for advanced resuscitation such as intubation, chest compression, and epinephrine. Every 30 s delay in initiation of PPV increased the risk of death or morbidity by 16%. The most effective interface for providing PPV in the early phases of resuscitation is still unclear. Laryngeal masks (LMs) are supraglottic airway devices that provide less invasive and relatively stable airway access without the need for laryngoscopy which have been studied as an alternative to face masks and endotracheal tubes in the initial stages of neonatal resuscitation. A meta-analysis found that LM is a safe and more effective alternative to face mask ventilation in neonatal resuscitation. LM is recommended as an alternative secondary airway device for the resuscitation of infants > 34 weeks by the International Liaison Committee on Resuscitation. It is adopted by various national neonatal resuscitation guidelines across the globe. Recent good-quality randomized trials have enhanced our understanding of the utility of laryngeal masks in low-resource settings. Nevertheless, LM is underutilized due to its variable availability in delivery rooms, providers’ limited experience, insufficient training, preference for endotracheal tube, and lack of awareness.

Comparison of I-gel and LMA Protector in Laparoscopic Cholecystectomy: A Randomized Controlled Trial

Aims

Comparison of the use of I-gel and Laringeal Mask Airway (LMA) Protector in laparoscopic cholecystectomy regarding the time and ease of insertion for supraglottic airway devices (SAD) and gastric tube (GT), airway sealing capacity, and postoperative complications.

Patients and Methods

Sixty-four American Society of Anaesthesiologists (ASA) I-III patients undergoing laparoscopic cholecystectomy were randomly allocated into two groups. After anesthesia induction, LMA Protector was inserted in Group LPRO (LMA Protector) (n = 33) and I-gel was inserted in Group IGEL (I-gel) (n = 31) patients. Time of SAD insertion, number of attempts, time, and ease of GT insertion were recorded. The peak inspiratory pressure (PIP) and oropharyngeal leak pressure (OLP) were measured at the time of SAD insertion, 10 min after insertion, 10 min after pneumoperitoneum, and just before the termination of pneumoperitoneum. The presence of bloodstains on SAD, sore throat, hoarseness, nausea, and pain in swallowing was assessed postoperatively. A P value of < 0.05 was accepted as statistically significant.

Result

Two patients in Group LPRO needed endotracheal intubation and were excluded from the study. The SAD insertion time was shorter in Group IGEL than in Group LPRO (13 ± 7.4 s vs. 18.8 ± 9.8 s). The number of attempts and success rate on the first attempt were similar in both groups. GT insertion time was shorter in Group IGEL than Group LPRO (11 ± 7.7 s vs. 21 ± 11 s). The insertion of GT was easier in Group IGEL. The OLP levels decreased during the pneumoperitoneum in Group LPRO while they remained constant in Group IGEL.

Conclusion

We observed that I-gel offers more stable airway sealing and easier GT insertion advantages when compared with LMA Protector in laparoscopic cholecystectomy.

Comparative evaluation of Air-Q blocker and Proseal laryngeal mask airway in patients undergoing elective surgery under general anaesthesia: A randomised controlled trial

Background and Aims:

The Air-Q blocker (Cook gas LLC, Mercury Medical, Clearwater, FL, USA) is a relatively new supraglottic airway device (SAD) with capability to serve as a conduit for intubation. As there is limited data on Air-Q blocker, the present study was performed to compare the efficacy of Air-Q blocker and Proseal laryngeal mask airway (PLMA) in patients undergoing elective surgery.

Methods:

A total of 90 American Society of Anesthesiologists (ASA) physical status I and II patients were randomly allocated to Air-Q blocker or PLMA group. Oropharyngeal leak pressure (OLP), insertion success, insertion time, ease of orogastric tube (OGT) insertion, fibreoptic visualisation of the glottis, haemodynamic and ventilation parameters, and complications at emergence and postoperatively were investigated.

Results:

OLPs were higher in PLMA group as compared to Air-Q blocker group (P = 0.002). Still, the OLP (27.5 ± 5.8 cm H₂O) was clinically effective in Air-Q blocker group. The mean time for successful insertion was significantly shorter for Air-Q blocker than PLMA (P = 0.019). The number of attempts to insert both the devices was comparable (P ≥ 0.05). Air-Q blocker provided a significantly better fibreoptic score than PLMA (P = 0.038). The two groups were comparable in terms of ease of OGT insertion, haemodynamics and ventilation parameters, and complications at emergence and postoperatively.

Conclusions:

Air-Q blocker provides a clinically effective OLP though PLMA provides a slightly better sealing function in patients undergoing laparoscopic and non-laparoscopic surgeries under general anaesthesia requiring neuromuscular blockade. Air-Q blocker has shorter insertion time and a better fibreoptic view of glottis as compared to PLMA.

Comparison of Intracuff Pressure and Postoperative Sore Throat Following Use of Laryngeal Mask Airway Protector With or Without Nitrous Oxide Anesthesia

PURPOSE

In general anesthesia, the laryngeal mask airway (LMA) is a frequently used effective option. The effect of nitrous oxide on intracuff pressure of the LMA and postoperative sore throat is well known; however, there are no studies related to the second-generation LMA Protector. The purpose of this study was to determine the differences in intracuff pressure and postoperative sore throat, depending on the use of nitrous oxide during general anesthesia using the LMA Protector.

DESIGN

This randomized double-blind prospective study was conducted among 88 patients aged 20 to 70 years.

METHODS

The cuff pressure started with a baseline of 40 cm H₂O and was measured using a digital cuff pressure manometer for 30 minutes. Postoperative sore throat, dysphonia, dysphagia, and numeric rating scale scores were also recorded.

FINDINGS

Over time, the intracuff pressure of the nitrous oxide group increased significantly compared with that of the air group. Furthermore, postoperative sore throat and pharyngolaryngeal complications were not significantly different between the two groups.

CONCLUSIONS

Intracuff pressure of the LMA Protector increased during anesthesia using nitrous oxide. When the anesthesia time was less than 2 hours, however, there was no difference in postoperative sore throat.

Two manoeuvres to facilitate the oral insertion of LMA CTrach™

Background and Aims:

LMA CTrach^TM, a new intubating conduit, has a thicker shaft compared to that of the intubating laryngeal mask airway (ILMA) due to the embedded optical fibres of the system. This causes difficulty during insertion despite normal mouth opening. Utility of two manoeuvres to overcome this was evaluated.

Methods:

From our experience with LMA CTrach^TM we found that two manoeuvres can be helpful to facilitate the insertion of LMA (a) dorsal and downward pressure over the shaft at the point where it hinges against the incisors while continuing the one handed rotational insertion of LMA (b) Lateral insertion of the LMA till the cuff is inside the oral cavity and then rotation of the LMA by 90° and then complete the insertion. A retrospective analysis of 200 insertions of LMA CTrach^TM was done to evaluate the utility of these manoeuvres.

Results:

Out of 200 insertions, 15 were found to be difficult. Manoeuvre “a” was applied in 13 cases to facilitate the insertion and manoeuvre “b” was applied in 2 cases where insertion was not possible despite manoeuvre “a'. Insertion was successful in these cases after the application of the described manoeuvres.

Conclusion:

The two manoeuvres described above can be useful when LMA CTrach^TM insertion into the oral cavity is obstructed by the incisor teeth.

A prospective observational cohort study on the incidence of postoperative sore throat in the pediatric population

BACKGROUND

Postoperative sore throat is common after general anesthesia. The incidence in pediatric anesthesia is variable, and the etiology unclear. Establishing risk factors would enable prevention and could improve quality of care.

AIMS

We performed a prospective single-center cohort study aiming to establish the incidence of postoperative sore throat in children undergoing GA with an endotracheal tube or laryngeal mask airway. Secondary aims were to identify independent risk factors for sore throat and the incidence of other postoperative complications including stridor, laryngospasm, nausea and vomiting, and delayed oral intake.

METHODS

Between November 2017 and April 2018, perioperative data were collected from children aged 5-16 years undergoing general, plastic, urology, renal, and orthopedic surgery. Patients completed a postoperative questionnaire within 24 hours of surgery.

RESULTS

We screened 334 children for inclusion at a tertiary pediatric hospital in the United Kingdom. One hundred and ninety-seven patients were included in the final analysis. The frequency of postoperative sore throat was 36.5%. Stridor occurred in 1.5%, laryngospasm 1.0%, postoperative nausea 59.4%, vomiting in recovery 4.6%, and delayed oral intake due to postoperative sore throat 30%. Nausea, vomiting, thirst, and pain were associated with a sore throat. Univariate analysis showed anesthesia longer than 2 hours, and use of an endotracheal tube was statistically associated with higher risk of sore throat. Over 50% of children with an endotracheal tube cuff pressure <20 cmH₂ O had a postoperative sore throat.

CONCLUSION

Postoperative sore throat is common in children. Endotracheal intubation is associated with a greater incidence than laryngeal mask airway use. A high rate of postoperative sore throat in children with endotracheal tube cuff pressures within the recommended range suggests multifactorial etiology. To confirm validity of the identified risk factors, we would recommend a larger prospective multi-center study.

Airway management using laryngeal mask airway (LMA) in a patient in a lateral decubitus position: A case report

RATIONALE

Airway management of patients in a lateral decubitus position (LDP), who cannot lie supine is challenging for anesthesiologists. In a previous study, laryngeal mask airway (LMA) was found to be superior to conventional endotracheal intubation in LDP.

PATIENT CONCERNS

A 38-year-old man diagnosed with type I neurofibromatosis presented with pain caused by a large hematoma (28 × 8 cm) located in the left upper back. On arrival at the operating theater, he was in a right LDP because of the aggravation of pain in the supine position.

DIAGNOSES

Laryngoscopy-guided endotracheal intubation was expected to be difficult in LDP.

INTERVENTIONS

After the induction of anesthesia, a non-inflatable LMA was introduced into the laryngopharynx with the patient in LDP. He was then maneuvered into a supine position and removal of the LMA was followed by endotracheal intubation.

OUTCOMES

The surgery for the removal of the hematoma was performed in a prone position. The airway intubated with an endotracheal tube was well maintained during the entire surgery.

LESSONS

LMA is a useful device for airway management in patients in LDP who cannot lie supine.

Endosonographic evaluation of the mediastinum through the i-gel O2 supraglottic airway device

INTRODUCTION

Endobronchial ultrasound (EBUS) is an endoscopic diagnostic procedure combining flexible fibrobronchoscopy with ultrasound techniques; it allows transbronchial needle aspiration biopsy for the diagnosis and staging of mediastinal masses. We present our preliminary experience with the use of the i-gel O₂ supraglottic airway device for management of EBUS procedures.

METHODS

An observational study on 39 patients who underwent EBUS under general anesthesia was performed. Airways were managed with i-gel O₂ by anesthesiologists unfamiliar with it. Data collected included patient characteristics, i-gel O₂ positioning, mechanical ventilation, procedure, and complications occurring during and after the EBUS.

RESULTS

The i-gel airway was successfully positioned during the first attempt in 34/39 cases (87.2%). No failed positioning was recorded. The EBUS scope easily passed through the i-gel in all patients and in 14 (35.6%) cases it was also inserted through the esophagus allowing the examination or fine needle aspiration of paraesophageal lymph nodes. In one case, during the EBUS procedure, the i-gel was dislocated but easily put in place again. During EBUS, air leakages were significant in 2 cases (5.1%) and minimal in 14 cases (35.9%). A brief self-solved laryngospasm and a bronchospasm during bronchoscopy were recorded. After recovery, no patients had dysphagia; mild odynophagia and pharyngodinia were referred by 2 (5.1%) and 12 (30.1%) patients, respectively.

CONCLUSIONS

The i-gel O₂ airway is easy to position and manage even for anesthesiologists unfamiliar with it. This supraglottic airway device is suitable for a complete endosonographic evaluation of the mediastinum.

A generalized multistage approach to oral and nasal intubation in infants with Pierre Robin sequence: A retrospective review

BACKGROUND

Airway management in children with Pierre Robin sequence in the infantile period can be challenging and frequently requires specialized approaches.

AIMS

The aim of this study was to review our experience with a multistage approach to oral and nasal intubation in young infants with Pierre Robin sequence.

METHODS

After IRB approval, we reviewed 13 infants with Pierre Robin sequence who underwent a multistage approach to intubation in the operating room for mandibular distractor or gastrostomy tube placement. All patients underwent awake placement of either an LMA-Classic™ #1 or ProSeal™ laryngeal mask airway size #1. General anesthesia was induced with sevoflurane, and patients were relaxed with rocuronium. The laryngeal mask airway was replaced with an air-Q^® 1.0. Children were then intubated through the air-Q^® 1.0 using a flexible fiberoptic bronchoscope. In cases that required a nasotracheal tube, the oral tube was left in place while a flexible fiberoptic bronchoscope loaded with a similar internal diameter nasal Ring-Adair-Elwyn (RAE) tube was introduced into the nares. Once the scope was in proximity to the glottis, the oral tube was removed and the patient was intubated with the nasal RAE over the fiberscope.

RESULTS

All 13 patients with Pierre Robin sequence were successfully intubated. We observed no periods of desaturation during placement and induction with the LMA-Classic™ or ProSeal™ laryngeal mask airway except in one patient who was in extremis in the neonatal intensive care unit and required emergent transport to the operating room with the laryngeal mask airway in place. We observed several brief periods of desaturation during the apneas associated with fiberoptic intubation.

CONCLUSION

In conclusion, we were able to use a ventilation-driven, multistaged approach using the unique properties of different supraglottic airways to facilitate oral and nasal intubation in 13 infants with Pierre Robin sequence.

Comparison of I-gel for general anesthesia in obese and nonobese patients

Context:

I-gel is a second-generation supraglottic airway device. Despite several studies on i-gel, there are very few studies on the use of i-gel in obese patients.

Aims:

The aim of the study was to compare the clinical performance of i-gel between obese and nonobese patients.

Settings and Design:

Prospective, controlled, nonrandomized, hospital-based study.

Subjects and Methods:

After obtaining informed consent, patients were divided into two groups of 16 patients each: group O consisted of patients with body mass index (BMI) >30 kg/m² and Group C consisted of patients with BMI 18.5–29.9 kg/m². I-gel was inserted after induction of anesthesia and muscle relaxation. Oropharyngeal leak pressure (OLP) (primary outcome variable), leak fraction, time taken to insert the device, ease of insertion, fiberoptic view of glottis through i-gel's airway tube, and adverse effects were recorded.

Statistical Analysis Used:

Data were analyzed using SPSS 20. Continuous, ordinal, and categorical variables were analyzed using students t-test, Mann–Whitney U–test, and Fischer's exact test, respectively.

Results:

OLP was slightly higher in Group O (25.38 ± 4.79 cm H₂O) but was not statistically different than Group C (27.38 ± 4.38 cm H₂O). Other parameters except weight and BMI (which were higher in Group O) were statistically similar in both groups. There was no statistical difference in side effects.

Conclusions:

We concluded that i-gel is as effective in obese patients as in nonobese patients when used for securing the airway for surgical procedures.

Two Cases of Bilateral Vocal Fold Mobility Impairment After LMA Use In 7 Months

OBJECTIVES

To increase awareness of vocal fold mobility impairment secondary to laryngeal mask airway (LMA) use in the operating room.

METHODS

We report 2 cases of bilateral vocal fold mobility impairment after LMA use within 7 months of each other. One patient is a 52-year-old female who developed this complication after orthopedic elbow surgery. The second case is a 75-year-old male who presented after undergoing inguinal hernia repair.

RESULTS

The patient from the first case required a 7-day hospital stay in the SICU due to airway compromise with spontaneous resolution of right-sided vocal fold immobility and improvement of symptoms. The 75-year-old male required direct laryngoscopy and bilateral true vocal fold injection medialization to correct his bilateral vocal fold paresis causing dysphonia and aspiration of liquids.

CONCLUSIONS

Bilateral vocal fold immobility secondary to LMA use is likely an underreported phenomenon of which otolaryngologists and anesthesiologists should be aware. Presentation may be severe, requiring hospitalization or operative intervention.

Flexion decreases the ventilation quality of the Ambu® AuraGain™ laryngeal mask in paralysed children: A prospective randomised crossover study

BACKGROUND

The influence of different head and neck positions on ventilation with the Ambu® AuraGain™ remains unevaluated in children. This study assessed the influence of different head and neck positions on ventilation with the AuraGain™ in paediatric patients.

METHODS

In this prospective, randomised crossover study, children ≤7 years of age who were scheduled for elective surgery under general anaesthesia were enrolled. An AuraGain™ was placed in all patients; mechanical ventilation was performed using a volume-controlled mode with a tidal volume of 10 mL/kg. Respiratory rate was adjusted to maintain a ET CO2 of 35-40 mm Hg. The oropharyngeal leak pressure, expiratory tidal volume, peak inspiratory pressure, ventilation score and fibreoptic bronchoscopic view score were assessed for the neutral head and neck position, and then for the flexed, extended and rotated head and neck positions in a random order.

RESULTS

Compared with the neutral position, the oropharyngeal leak pressure increased in the flexed position (P < .001), and decreased in the extended (P = .014) and rotated position (P = .002). The expiratory tidal volume and ventilation score were significantly reduced during flexion (all P < .005), and were comparable among the neutral, extended and rotated positions. The fibreoptic score improved in the extended and rotated position (all P < .001). Only the flexion ventilation score was lower compared with the neutral position (P = .014).

CONCLUSIONS

Clinically, the flexed head and neck positions negatively affected ventilation due to obstruction of the airway. Ventilation with AuraGain™ can be effectively performed with the head and neck in the neutral, extended and rotated position in paediatric patients.

Laryngeal Mask Airway Protector™ for intubation and extubation in thyroid surgeries: A case report

The laryngeal mask airway (LMA) Protector™ has recently made its way into clinical practice. As little is reported on this novel supraglottic airway device, we describe our experiences through intubation and Bailey manoeuvre using the LMA Protector™, and the assessment of vocal cord mobility using a flexible bronchoscope through it in three patients undergoing hemithyroidectomies.

Current practice patterns of supraglottic airway device usage in paediatric patients amongst anaesthesiologists: A nationwide survey

Background and Aims:

Supraglottic airway devices (SGADs) are increasingly being used for airway management in paediatric patients undergoing general anaesthesia. This survey was designed to assess the nationwide practice patterns of SGAD usage in paediatric patients.

Methods:

A questionnaire of 28 questions was circulated amongst 16,532 members of the Indian Society of Anaesthesiologists through online survey engine Google Forms^® and served manually to 500 delegates attending the Asian Society of Paediatric Anaesthesiologists conference 2017. Percentage, mean and standard deviation were calculated using Microsoft Excel 2016 (Redmond, WA, USA).

Results:

Four hundred and five (2.3%) valid responses were obtained. The most commonly used device was i-gel^© (60.74%). Three hundred and four (75.06%) respondents had access to second-generation SGADs. Second-generation devices (60.74%) were more commonly used than first-generation devices (39.26%). Anaesthesiologists utilised SGADs in various challenging scenarios such as in the difficult airway (53.33%), remote locations (55.47%), ophthalmologic (38.77%) and long-duration surgeries (17.53%). Sixty per cent respondents did not use SGADs in laparoscopic surgery. Disposable SGADs were reused by 77.28% respondents. Oropharyngeal seal and intracuff pressures were not measured by 86.91% and 56.92% respondents, respectively. Difficulty in size selection (84.19%), securing position (82.22%) and maintaining unobstructed ventilation (78.76%) were common problems encountered while using SGADs.

Conclusion:

Although there is a widespread use of second-generation SGADs in Indian paediatric anaesthesia, safe practices such as using capnography, measurement of oropharyngeal seal pressure, cuff pressure and appropriate disinfection are lacking.

Effectiveness of tip rotation in fibreoptic bronchoscopy under different experimental conditions: an in vitro crossover study

Background

Proper manipulation of fibreoptic bronchoscopes is essential for successful tracheal intubation or diagnostic bronchoscopy. Failure of proper navigation and rotation of the fibrescope may lead to difficulties in advancing the fibrescope and might also be responsible for (unnecessary) difficulties and delays in fibreoptic tracheal intubation, with subsequent hypoxaemia. The present study, therefore, aimed to assess the effectiveness of tip rotation in flexible bronchoscopes in different experimental conditions.

Methods

Five differently sized pairs of fibrescopes (outer diameters of 2.2, 2.4, 3.5, 4.2, and 5.2 mm) were inserted into paediatric airway manikins via an appropriately sized laryngeal mask and were turned clockwise or anticlockwise at the fibrescope body or cord to 45, 90, and 180°, with the cord held either straight or bent. The primary outcome measure was the ratio of rotation measured at the tip over the rotation performed with the fibrescope body or cord.

Results

Overall, the 'body' turn was significantly less effective when a bent cord was present (mean difference ranging from 29.8% (95% confidence interval 8.8-50.9) to 117.4% (93.6-141.2). This difference was diminished when the 'cord' turn was performed. Smaller fibrescopes, with outer diameters of 2.2 and 2.4 mm, were inferior with respect to the transmission of 'body' rotation to the tip.

Conclusions

'Cord' turning of the fibrescope appears to be more effective in rotating the tip than a turn of the fibrescope 'body' only. Straightening the fibrescope cord and combined 'body' and 'cord' turning are recommended.

Iatrogenic Intramural Dissection of the Esophagus after Insertion of a Laryngeal Mask Airway

In pediatric patients, a laryngeal mask airway (LMA) is usually used during minor surgeries that require general anesthesia. No esophageal injury has been reported after insertion of an LMA. We report a case of an esophageal injury with intramural dissection after an i-gel^® (size, 1.5; Intersurgical Ltd.) insertion in a pediatric patient. A 2-month-old male infant was hospitalized for left inguinal herniorrhaphy. After induction of anesthesia, a trained resident tried to insert an i-gel^® . However, it was only successful after three attempts. Dysphagia was sustained until postoperative day 10, and the pediatrician observed duplication of the esophagus on gastroendoscopy. However, a whitish mucosal lesion, which looked like a scar, was observed, and previous lesions suggestive of esophageal duplication were almost healed on postdischarge day 11. His condition was diagnosed as dysphagia and esophagitis due to an esophageal laceration, not esophageal duplication. He was scheduled for symptomatic treatment with a proton pump inhibitor. In conclusion, although an esophageal injury or perforation in pediatric patients is rare, an LMA insertion or a procedure such as aspiration or nasogastric tube insertion should be performed gently to avoid a possible injury to the esophagus in pediatric patients.

Comparison of actual and ideal body weight for selection of appropriate size of ProSeal™ laryngeal mask airway in overweight and obese patients: A prospective, randomised study

BACKGROUND AND AIMS

The ProSeal™ laryngeal mask airway (PLMA) has advantages of providing better cuff seal and the presence of a gastric drain tube. The manufacturer recommends actual body weight (ABW) for size selection. Pharyngeal area reduces with increase in body mass index (BMI); hence, in overweight patients, PLMA selected on ABW may not fit well. We hypothesised that the ideal body weight (IBW) would be more appropriate in size selection of PLMA.

METHODS

This randomised, single-blind study included 124 patients of 20-60 years and American Society of Anesthesiologists Class I-II, with BMI >25. Patients were randomly divided into two groups. In Group ABW, PLMA was selected based on ABW (62 patients) and in Group IBW, PLMA was selected based on IBW (62 patients). The primary outcome was the first-attempt insertion success rate. Oropharyngeal air leaks, gastric air leaks, drain tube air leaks, insertion difficulty scores and postoperative complications were assessed. Fibre-optic view (Grade I-IV) was assessed for proper placement by a blinded assessor. Statistical analyses were performed using Chi-square test or Fisher's exact test.

RESULTS

First-attempt insertion success rate and overall insertion success rates were similar in both the groups. Group IBW patients had significantly less resistance during insertion, lower peak airway pressures, successful nasogastric tube insertions, better fibre-optic views and less post-operative complications. Oropharyngeal leak pressure and instrumentation used for insertion were comparable.

CONCLUSION

IBW is preferable for the size selection of the PLMA in overweight and obese patients compared to the ABW.

A Prospective Randomised Clinical Trial for the Comparison of Two Techniques for the Insertion of Proseal Laryngeal Mask Airway in Adults-Index Finger Insertion Technique versus 90° Rotation Technique

OBJECTIVE

The 90° rotation technique for inserting the Proseal laryngeal mask airway (PLMA) is reported to be better than the standard index finger insertion technique to improve the insertion success rate. The objective of this study was to evaluate and compare the ease of insertion through the 90° rotation and standard insertion techniques in terms of number of attempts, duration of insertion and occurrence of complications.

METHODS

One hundred and twenty adult patients were allocated to either a standard technique group or rotation technique group with 60 patients in each. In the rotation technique group, the entire cuff of the PLMA was placed in the patient's mouth in a midline approach without finger insertion, rotated 90° counter-clockwise around the patient's tongue, advanced and rotated back until resistance was felt.

RESULTS

The success rate of the rotation technique group at the first insertion attempt was greater than that of the standard index finger insertion technique (98% vs. 78%; p=0.001), and less time for insertion was required (11.88±3.62 s vs. 25.98±10.92 s; p<0.0001). The incidence of post-operative sore throat was lower (15% vs. 38.34%; p=0.0067), and blood staining on the PLMA was less (11.7% vs. 45%; p<0.0001). The increase in the mean arterial pressure was more in the standard technique group.

CONCLUSION

The 90° rotation technique has a higher success rate at first insertion attempt for inserting the ProSeal LMA than the index finger insertion technique with less time for insertion and fewer side effects.

Laryngeal mask airway protector™: Advanced uses for laparoscopic cholecystectomies

The laryngeal mask airway (LMA) Protector™ is a second-generation perilaryngeal sealer type supraglottic airway device recently introduced into clinical practice. We describe our initial experiences with the use of the LMA Protector™ in three patients undergoing laparoscopic cholecystectomies. In all patients, we found the LMA Protector™ to have acceptable placements on the first attempt, adequate oropharyngeal leak pressures and ventilation adequacy.

A cohort evaluation of clinical use and performance characteristics of Ambu® AuraGain™: A prospective observational study

BACKGROUND AND AIMS

Ambu^® AuraGain™ (AG) (Ambu, Ballerup, Denmark) is a supraglottic device which has a design facilitating its use as a conduit for intubation. We designed this prospective observational study to assess the ease of AG placement in paralysed patients, determine its position and alignment to the glottis and assess its utility as a conduit for intubation.

METHODS

One hundred patients, aged 18-60 years, American Society of Anesthesiologists physical status I-II, undergoing elective surgery under general anaesthesia were included in the study. The ease and number of attempts for successful insertion, ease of gastric tube insertion, leak pressures, fibre-optic grade of view, number of attempts and time for tracheal intubation, time for AG removal and complications were recorded. The mean, standard deviation (SD), interquartile range (IQR) and range were calculated. The upper limit of confidence interval for overall failure rate was calculated using Wilson's score method.

RESULTS

AG was successfully inserted in all patients. The mean (SD) time taken for insertion was 17.32 (8.48) s. The median [IQR] leak pressures were 24 [20-28] cm of H₂O. Optimal laryngeal view for intubation was obtained in 68 patients. Eighty-eight patients could be intubated in the first attempt. Five patients could not be intubated. The overall failure rate of device was 9%.

CONCLUSION

AMBU^® AuraGain™ serves as an effective ventilating aid, but caution is suggested before using it as a conduit for endotracheal intubation.

Comparison of the i-gel and other supraglottic airways in adult manikin studies: Systematic review and meta-analysis

BACKGROUND

The i-gel has a gel-like cuff composed of thermoplastic elastomer that does not require cuff inflation. As the elimination of cuff inflation may shorten insertion time, the i-gel might be a useful tool in emergency situations requiring prompt airway care. This systematic review and meta-analysis of previous adult manikin studies for inexperienced personnel was performed to compare the i-gel with other supraglottic airways.

METHODS

We searched PubMed, the Cochrane Library, and EMBASE for eligible randomized controlled trials (RCTs) published before June 2015, including with a crossover design, using the following search terms: "i-gel," "igel," "simulation," "manikin," "manikins," "mannequin," and "mannequins." The primary outcomes of this review were device insertion time and the first-attempt success rate of insertion.

RESULTS

A total of 14 RCTs were included. At the initial assessment without difficult circumstances, the i-gel had a significantly shorter insertion time than the LMA Classic, LMA Fastrach, LMA Proseal, LMA Unique, laryngeal tube, Combitube, and EasyTube. However, a faster insertion time of the i-gel was not observed in comparisons with the LMA Supreme, aura-i, and air-Q. In addition, the i-gel did not show the better results for the insertion success rate when compared to other devices.

CONCLUSION

The findings of this meta-analysis indicated that inexperienced volunteers placed the i-gel more rapidly than other supraglottic airways with the exception of the LMA Supreme, aura-i, and air-Q in manikin studies. However, the quicker insertion time is clinically not relevant. The unapparent advantage regarding the insertion success rate and the inherent limitations of the simulation setting indicated that additional evidence is necessary to confirm these advantages of the i-gel in an emergency setting.

Comparison between supraglottic airway devices and endotracheal tubes in patients undergoing laparoscopic surgery: A systematic review and meta-analysis

BACKGROUND

Comparisons between the efficacies of supraglottic airway devices (SGAs) and endotracheal tubes (ETTs) in patients undergoing laparoscopic surgeries have yielded conflicting results. Therefore, in this meta-analysis, we compared the clinical performance and incidence of complications between SGAs and ETT intubation in laparoscopic surgery.

METHODS

A comprehensive search was conducted using MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials, and Google Scholar to identify randomized controlled trials that compared SGAs with ETTs in laparoscopic surgery.

RESULTS

In total, 1433 patients from 17 studies were included in the final analysis. SGAs and ETTs showed no difference in insertion success rate on the first attempt (relative risk [RR] 1.01, 95% confidence interval [CI] 0.99-1.03), insertion time (standardized mean difference 1.57, 95% CI -3.74 to 0.61), and oropharyngeal leak pressure (OLP) (mean difference -2.54, 95% CI -7.59 to 2.50). The incidence of desaturation (RR 3.65, 95% CI 1.39-9.62), gastric insufflations (RR 0.90, 95% CI 0.48-1.71), regurgitation (RR 0.98, 95% CI 0.02-49.13), and aspiration (RR 0.99, 95% CI 0.01-78.4) also showed no intergroup differences. However, the incidence of laryngospasm (RR 3.12, 95% CI 1.29-7.52), cough at removal (RR 6.68, 95% CI 4.70-9.48), dysphagia (RR 1.47, 95% CI 1.12-1.95) or dysphonia (RR 4.41, 95% CI 1.25-15.55), sore throat (RR 1.60, 95% CI 1.33-1.93), and hoarseness (RR 1.53, 95% CI 1.29-1.81) was higher in the ETT group than in the SGA group.

CONCLUSIONS

The incidence of laryngospasm, cough at removal, dysphagia or dysphonia, sore throat, and hoarseness were higher in the ETT group than in the SGA group. However, the groups showed no differences in the rate of insertion success on the first attempt, insertion time, OLP, and other complications. Therefore, SGAs might be clinically more useful as effective airways in laparoscopic surgery.

Standard versus Rotation Technique for Insertion of Supraglottic Airway Devices: Systematic Review and Meta-Analysis

PURPOSE

Supraglottic airway devices have been widely utilized as an alternative to tracheal intubation in various clinical situations. The rotation technique has been proposed to improve the insertion success rate of supraglottic airways. However, the clinical efficacy of this technique remains uncertain as previous results have been inconsistent, depending on the variable evaluated.

MATERIALS AND METHODS

We systematically searched PubMed, Embase, and the Cochrane Central Register of Controlled Trials in April 2015 for randomized controlled trials that compared the rotation and standard techniques for inserting supraglottic airways.

RESULTS

Thirteen randomized controlled trials (1505 patients, 753 with the rotation technique) were included. The success rate at the first attempt was significantly higher with the rotation technique than with the standard technique [relative risk (RR): 1.13; 95% confidence interval (CI): 1.05 to 1.23; p=0.002]. The rotation technique provided significantly higher overall success rates (RR: 1.06; 95% CI: 1.04 to 1.09; p<0.001). Device insertion was completed faster with the rotation technique (mean difference: -4.6 seconds; 95% CI: -7.37 to -1.74; p=0.002). The incidence of blood staining on the removed device (RR: 0.36; 95% CI: 0.27 to 0.47; p<0.001) was significantly lower with the rotation technique.

CONCLUSION

The rotation technique provided higher first-attempt and overall success rates, faster insertion, and a lower incidence of blood on the removed device, reflecting less mucosal trauma. Thus, it may be considered as an alternative to the standard technique when predicting or encountering difficulty in inserting supraglottic airways.

Overinflation of the cuff and pressure on the neck reduce the preventive effect of supraglottic airways on pulmonary aspiration: an experimental study in human cadavers

BACKGROUND

The oesophageal leak pressure is defined as the pressure which breaks the seal between the cuff of a supraglottic airway and the peri-cuff mucosa, allowing penetration of fluid into the pharynx and the oral cavity. As a consequence, a decrease in this variable increases the risk of reflux and can lead to pulmonary aspiration. The aim of this study was to analyse the effects of cuff overinflation and pressure on the neck on the oesophageal leak pressure of seven supraglottic airways.

METHODS

Three laryngeal masks, two laryngeal tubes, and two oesophageal-tracheal tubes were tested in an experimental setting. In five human cadavers, we simulated a sudden increase in oesophageal pressure. To measure baseline values (control), we used an intracuff pressure as recommended by the manufacturer. The first intervention included overinflation of the cuff by applying twice the amount of pressure recommended. A second intervention was defined as external pressure on the neck.

RESULTS

The oesophageal leak pressure was decreased for laryngeal masks (control, 28 cm H2O; overinflation, 9 cm H2O; pressure on the neck, 8 cm H2O; P<0.01) and for laryngeal tubes (control, 68 cm H2O; overinflation, 37 cm H2O; pressure on the neck, 39 cm H2O; P<0.01) and was unaffected for oesophageal-tracheal tubes (control, 126 cm H2O; overinflation/pressure on the neck, 130 cm H2O; n.s.).

CONCLUSION

Cuff overinflation and pressure on the neck can enhance the risk of gastro-oesophageal reflux when using supraglottic airways. Therefore, both manoeuvres should be avoided in clinical practice.

A randomized comparison of pediatric-sized Streamlined Liner of Pharyngeal Airway and Laryngeal Mask Airway-Unique in paralyzed children

BACKGROUND

The pediatric-sized Streamlined Liner of Pharyngeal Airway (SLIPA) is a new supraglottic airway device for children.

AIMS

The aim of this study was to compare the clinical performance of the pediatric-sized SLIPA with the Laryngeal Mask Airway-Unique in paralyzed children under positive pressure-controlled ventilation (PCV).

METHODS

One hundred children, aged 2 months to 12 years with American Society of Anesthesiologists physical status I-II were enrolled and randomly allocated to the SLIPA group or the Laryngeal Mask Airway-Unique group (50 patients in each group). The primary outcome variable was oropharyngeal leak pressure. Other outcome variables were first insertion success rate, insertion time, minor airway interventions required for successful insertion, intraoperative dislodgement, ventilatory data, and perioperative complications.

RESULTS

The insertion characteristics, ventilation data, and perioperative complications were comparable between the two groups. The leak pressure of the SLIPA was significantly higher than that of the Laryngeal Mask Airway-Unique [median (IQR): 25 (22-30) cm H2O vs. 21 (19-26) cm H2O, respectively; mean ± sd: 25.3 ± 4.6 cm H2O vs. 22.6 ± 4.8 cm H2O, respectively; P = 0.006]. The incidence of intraoperative dislodgment was significantly lower in the SLIPA group than in the Laryngeal Mask Airway-Unique group (0 vs. 6 patients, respectively; P = 0.027).

CONCLUSIONS

In conclusion, both the SLIPA and the Laryngeal Mask Airway-Unique can be used effectively without severe complications in paralyzed children. Additionally, the SLIPA provides a better airway seal and better intraoperative position stability than the Laryngeal Mask Airway-Unique.

Comparison of Airway Management Methods in Entrapped Patients: A Manikin Study

INTRODUCTION

Endotracheal intubation remains one of the most challenging skills in prehospital care. There is a minimal amount of data on the optimal technique to use when managing the airway of an entrapped patient. We hypothesized that use of a blindly placed device would result in both the shortest time to airway management and highest success rate.

METHODS

A difficult airway manikin was placed in a cervical collar and secured upside down in an overturned vehicle. Experienced paramedics and prehospital registered nurses used four different methods to secure the airway: direct laryngoscopy, digital intubation, King LT-D, and CMAC video laryngoscopy. Each participant was given three opportunities to secure the airway using each technique in random order. A study investigator timed each attempt and confirmed successful placement, which was determined upon inflation of the manikin's lungs. Intubation success rates were analyzed using a general estimating equations model to account for repeated measures and a linear mixed effects model for average time.

RESULTS

Twenty-two prehospital providers participated in the study. The one-pass success rate for the King LT-D was significantly higher than direct laryngoscopy (OR 0.048, CI 0.006-0.351, p < 0.01) and digital intubation (OR 0.040, CI 0.005-0.297, p < 0.01). However, there was no statistical difference between the one-pass success rate of the King LT-D and CMAC video laryngoscopy (OR 0.302, 95% CI 0.026-3.44, p = 0.33). The one-pass median placement time of the King LT-D (22 seconds, IQR 17-26) was significantly lower (p < 0.001) than direct laryngoscopy (60 seconds, IQR 42-75), digital intubation (38 seconds, IQR 26-74), and the CMAC (51 seconds, IQR 43-76).

CONCLUSIONS

In this study, while the King LT-D offered the quickest airway placement, success rates were not significantly greater than intubation using the CMAC video laryngoscope. Intubation using direct laryngoscopy and digital intubation were less successful and took more time. Use of a blindly placed device or a video laryngoscope may provide the best avenues for airway management of entrapped patients.

An update on newer pediatric supraglottic airways with recommendations for clinical use

Supraglottic airways are an established part of routine and emergency pediatric airway management, including use in difficult airways and neonatal resuscitation. With the introduction of newer supraglottic airways in children, efficacy can only be determined by comparing these devices with those that are already well established (laryngeal mask airway Classic and laryngeal mask airway ProSeal). This narrative review aims to present the current literature on these newer supraglottic airways and give recommendations for their use in various clinical scenarios based on the existing evidence.

Supraglottic airway devices

Supraglottic airway devices (SADs) are used to keep the upper airway open to provide unobstructed ventilation. Early (first-generation) SADs rapidly replaced endotracheal intubation and face masks in > 40% of general anesthesia cases due to their versatility and ease of use. Second-generation devices have further improved efficacy and utility by incorporating design changes. Individual second-generation SADs have allowed more dependable positive-pressure ventilation, are made of disposable materials, have integrated bite blocks, are better able to act as conduits for tracheal tube placement, and have reduced risk of pulmonary aspiration of gastric contents. SADs now provide successful rescue ventilation in > 90% of patients in whom mask ventilation or tracheal intubation is found to be impossible. However, some concerns with these devices remain, including failing to adequately ventilate, causing airway damage, and increasing the likelihood of pulmonary aspiration of gastric contents. Careful patient selection and excellent technical skills are necessary for successful use of these devices.

Intraoperative apnea in children after buffered 5% povidone-iodine site sterilization for strabismus surgery

BACKGROUND

Presurgical preparation for ocular surgery typically utilizes a buffered 5% povidone-iodine preparation solution. It was our observation that a significant number of spontaneously ventilating patients under sevoflurane anesthesia would become apneic upon ophthalmic instillation of this solution. This study was performed to confirm or refute this observation and to determine whether there were any patient variables that might predict this phenomenon.

METHODS

After Institutional Review Board (IRB) approval, thirty pediatric patients scheduled for strabismus surgery were enrolled. Anesthesia was induced and maintained with sevoflurane via laryngeal mask airway, and all patients were breathing spontaneously. All patients received preoperative sedation with oral midazolam (0.5 kg·kg(-1), maximum 12 mg). Presurgical preparation was performed with saline wash followed by instillation of buffered 5% povidone-iodine solution. Respiratory rate was recorded at the time of surgical preparation. Apnea was defined as lack of respiratory effort for 20 s or greater.

RESULTS

Data from twenty-eight children (ages 1.4-11 years) were ultimately recorded. Fifteen of the twenty-eight patients developed apnea (median duration 40, IQR 37, range 20-262 s) at the time of surgical site preparation.

CONCLUSIONS

Apnea at the time of ocular preparation with buffered 5% povidone-iodine solution is common. The precise mechanism of this response is unknown.

Laryngeal mask airway placement in children prior to an intravenous line utilizing heart rate as an indicator of anesthetic depth

INTRODUCTION

The usual practice in pediatric anesthesia cases requiring a laryngeal mask airway is to place an intravenous line (IV) prior to laryngeal mask airway placement. A different approach that has several clinical advantages is to place the laryngeal mask airway prior to the IV. We describe our experience with this technique, using heart rate as an indicator of adequate anesthetic depth. In addition, we analyzed heart rate data in children undergoing sevoflurane inductions, looking for age-related differences.

METHODS

Following a sevoflurane induction, heart rates were recorded every 12 s for 3 min in 127 ASA I-II children under age 7. Laryngeal mask airway placement occurred when the heart rate dropped at least 10% from its maximum level or at 3 min. Ease of laryngeal mask airway placement was graded using a scale from 0 to 3. Endtidal sevoflurane concentration, occurrence of laryngospasm and blood pressure at laryngeal mask airway placement were also recorded.

RESULTS

The laryngeal mask airway was successfully placed on the first attempt in all 127 children. Easy placement was noted in 98.4%. The youngest children's heart rates peaked earlier than the oldest (P < 0.001), while time to laryngeal mask airway placement increased with increasing age (P < 0.0001).

CONCLUSIONS

Laryngeal mask airway placement before an IV is a safe alternative to the usual mask-IV-laryngeal mask airway sequence. Our data compare favorably to other studies where ease of laryngeal mask airway placement was reported. This technique has several advantages including securing the airway first for an anticipated difficult IV placement. Heart rate changes during a sevoflurane induction appear to be age-dependent.

Laryngeal mask airway versus endotracheal tube for percutaneous dilatational tracheostomy in critically ill adult patients

BACKGROUND

Percutaneous dilatational tracheostomy (PDT) is one of the most common bedside surgical procedures performed in critically ill adult patients on intensive care units (ICUs) who require long-term ventilation. PDT is generally associated with relevant life-threatening complications (e.g. cuff rupture leading to possible hypoxia or aspiration, puncture of the oesophagus, accidental extubation, mediastinitis, pneumothorax, emphysema). The patient's airway can be secured with an endotracheal tube (ETT) or a laryngeal mask airway (LMA).

OBJECTIVES

To assess the safety and effectiveness of ETT versus LMA in critically ill adult patients undergoing PDT on the ICU.This review addresses the following research questions.1. Is an LMA more effective than an ETT in terms of procedure-related or all-cause mortality?2. Is an LMA safer than an ETT in terms of procedure-related life-threatening complications during a PDT procedure?3. Does use of an LMA influence the conditions for performing a tracheostomy (e.g. duration of procedure)?

SEARCH METHODS

We searched the Cochrane Database of Systematic Reviews (CDSR); the Cochrane Central Register of Controlled Trials (CENTRAL) 2013, Issue 6 (part ofThe Cochrane Library); MEDLINE (from 1984 to 27 June 2013) and EMBASE (from 1984 to 27 June 2013). We searched for reports of ongoing trials in the metaRegister of Controlled Trials (mRCT). We handsearched for relevant studies in conference proceedings of the International Symposium on Intensive Care and Emergency Medicine (ISICEM), the Annual Congress of the European Society of Intensive Care Medicine (ESICM), the Annual Congress of the Society of Critical Care Medicine (SCCM), the American Thoracic Society (ATS) and the Annual Meeting of the American College of Chest Physicians (ACCP). We contacted study authors and experts concerning unpublished data and ongoing trials. We searched for further relevant studies in the reference lists of all included trials and of relevant systematic reviews identified in theCDSR.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) that compared use of endotracheal tubes versus laryngeal mask airways in critically ill adult patients undergoing PDT on the ICU. We imposed no restrictions with regard to language, timing or technique of PDT performed.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed the eligibility and methodological quality of each study and carried out data extraction. We resolved disagreements by discussion. Our primary outcomes were all-cause mortality, procedure-related mortality and tally of participants with one or more serious adverse events. When available, we reported on our secondary outcomes, which included duration of the procedure, failure of the procedure requiring conversion to any other procedure, time to extubation after tracheostomy, length of ICU stay after tracheostomy, length of hospital stay after tracheostomy and any other serious adverse events. When possible, we combined homogeneous studies for meta-analysis. We used the risk of bias tool of The Cochrane Collaboration to assess the internal validity of all included studies in six different domains.

MAIN RESULTS

We included in this review eight RCTs involving 467 participants. The included trials exclusively assessed critically ill participants (e.g. with head injury, neurological disease, multi-trauma, sepsis, acute respiratory failure (ARF) and/or chronic obstructive pulmonary disease (COPD)). Internal validity was considerably low in studies with a high or unclear risk of bias. The main reason for this was low methodological quality or missing data, even after study authors were contacted. Study size was generally small, with a minimum of 40 and a maximum of 73 participants. Only one study (40 participants) reported on overall mortality, showing no clear evidence of a difference between treatment groups (risk ratio (RR) 1.5, 95% confidence interval (CI) 0.28 to 8.04, Fisher test P value 1.0, low-quality evidence). Four studies (231 participants) reported that no procedure-related deaths occurred with any intervention. Seven studies reported the numbers of participants with adverse events, showing no clear evidence of benefit of either LMA or ETT during PDT (RR 0.73, 95% CI 0.35 to 1.52, P value 0.41, low-quality evidence). The tally of participants in included studies with adverse events ranged from 0% to 33% in the LMA group and from 0% to 50% in the ETT group. However, the duration of the procedure was significantly shorter in the LMA group (mean difference (MD) -1.46 minutes, 95% CI -1.92 to -1.01 minutes, 324 participants, P value ≤ 0.00001, low-quality evidence). No clear evidence of a difference between ETT and LMA groups was found for all other outcomes. Only one study provided follow-up data for late complications related to the intervention, showing no clear evidence of benefit for any treatment group.

AUTHORS' CONCLUSIONS

Evidence on the safety of LMA for PDT is too limited to allow conclusions to be drawn on its efficacy or safety compared with ETT. Although the LMA procedure is shorter because of optimal visual conditions, its effect on especially late complications has not been investigated sufficiently. Studies focusing on late complications and relevant patient-related outcomes are necessary for definitive conclusions on safety issues related to this procedure.

Perfusion index versus non-invasive hemodynamic parameters during insertion of i-gel, classic laryngeal mask airway and endotracheal tube

Background:

Perfusion index (PI) is a non-invasive numerical value of peripheral perfusion obtained from a pulse oximeter. In this study, we evaluated the efficacy of PI for detecting haemodynamic stress responses to insertion of i-gel, laryngeal mask airway (LMA) and endotracheal tube and compare, its reliability with the conventional haemodynamic criteria in adults during general anaesthesia.

Methods:

Sixty patients scheduled for elective general surgery under general anaesthesia were randomised to three groups. (i-gel, LMA and ET groups (n=20/group). Heart rate (HR) (positive if ≥10 bpm), systolic blood pressure (SBP), diastolic blood pressure (DBP) (positive if ≥15 mm Hg) and PI (positive if ≤10%) were monitored for 5 min after insertion. Main outcome measures: SBP, DBP, HR and PI were measured before induction of anaesthesia and before and after insertion of the airway device.

Results:

Insertion of airway devices produced significant increases in HR, SBP and DBP in LMA and ET groups. Moreover, PI was decreased significantly by 40%, 100% and 100% in the three groups. Using the PI criterion, the sensitivity was 100% (CI 82.4-100.0%). Regarding the SBP and DBP criterions, the sensitivity was 44.4% (CI 24.6-66.3%), 55.6% (CI 33.7-75.4%) respectively. Also, significant change in the mean PI over time (from pre-insertion value to the 1^st min, 3^rd min, until the 4^th min after insertion without regard the device type), (P<0.001).

Conclusion:

PI is a reliable and easier alternative to conventional haemodynamic criteria for detection of stress response to insertion of i-gel, LMA and ET during propofol fentanyl isoflurane anaesthesia in adult patients.

Comprehensive airway management of patients with maxillofacial trauma

Airway management in patients with maxillofacial trauma is complicated by injuries to routes of intubation, and the surgeon is frequently asked to secure the airway. Airway obstruction from hemorrhage, tissue prolapse, or edema may require emergent intervention for which multiple intubation techniques exist. Competing needs for both airway and surgical access create intraoperative conflicts during repair of maxillofacial fractures. Postoperatively, edema and maxillomandibular fixation place the patient at risk for further airway compromise.

Comparison of bougie-guided insertion of Proseal laryngeal mask airway with digital technique in adults

The Proseal™ laryngeal mask airway (PLMA™, Laryngeal Mask Company, UK) was designed to improve ventilatory characteristics and offer protection against regurgitation and gastric insufflation. The PLMA is a modified laryngeal mask airway with large ventral cuff, dorsal cuff and a drain tube. These modifications improve seal around glottis and enable better ventilatory characteristics. The drain tube prevents gastric distension and offers protection against aspiration. There were occasional problems, like failed insertion and inadequate ventilation, in placing PLMA™ using the classical digital technique. To overcome these problems, newer placement techniques like thumb insertion technique, introducer tool placement and gum elastic bougie (GEB)-aided placement were devised. We compared classical digital placement of PLMA™ with gum elastic bougie-aided technique in 60 anaesthetised adult patients (with 30 patients in each group) with respect to number of attempts to successful placement, effective airway time, airway trauma during insertion, postoperative airway morbidity and haemodynamic response to insertion. The number of attempts to successful placement, airway trauma during insertion and haemodynamic response to insertion were comparable among the two groups, while effective airway time and oropharyngeal leak pressure were significantly higher in bougie- guided insertion of PLMA. Postoperatively, sore throat was more frequent with digital technique while dysphagia was more frequent with bougie guided technique. Hence gum elastic bougie guided, laryngoscope aided insertion of PLMA is an excellent alternate to classical digital technique.