Supraglottic devices for airway management in awake craniotomy

Comparing leak pressure of LMA® ProSeal™ versus i-gel® at head rotation: a randomized controlled trial

PURPOSE

The effect of head rotation on supraglottic airway (SGA) oropharyngeal leak pressure (OPLP) has not been well elucidated. The aim of this study was to help clarify which SGA device provides higher OPLP at head-rotated position.

METHODS

Patients who underwent elective surgery under general anesthesia were enrolled and randomly divided into laryngeal mask airway (LMA®) ProSeal™ and i-gel® groups. The allocated SGA device was inserted under anesthesia. The primary outcome was OPLP, and secondary outcomes were ventilation score, expiratory tidal volume, and maximum pressure under volume-controlled ventilation (VCV) with an inspiratory tidal volume of 10 mL·kg-1 ideal body weight and fibreoptic view of the vocal cords at 0°, 30°, and 60° head rotation.

RESULTS

Data from 78 and 76 patients were analyzed in the LMA ProSeal and i-gel groups, respectively. The mean (standard deviation) OPLP of the LMA ProSeal was significantly higher than that of the i-gel at the 60° head-rotated position (LMA ProSeal, 20.4 [6.5] vs i-gel, 16.9 [7.8] cm H2O; difference in means, 3.6; adjusted 95% confidence interval, 0.5 to 6.6; adjusted P = 0.02, adjusted for six comparisons). The maximum pressure under VCV at 60° head rotation was significantly higher in the LMA ProSeal group than in the i-gel group. The expiratory tidal volume of the LMA ProSeal did not significantly change with head rotation and was significantly higher than that of the i-gel at 60° head rotation. Ventilation score, fibreoptic view of the vocal cords, and complications were not significantly different between the ProSeal and i-gel groups.

CONCLUSIONS

The LMA ProSeal provides higher OPLP than the i-gel at a 60° head-rotated position under general anesthesia.

TRIAL REGISTRATION

Japan Registry of Clinical Trials (https://jrct.niph.go.jp) (JRCT1012210043); registered 18 October 2021.

Severe gastric insufflation and consequent atelectasis caused by gas leakage using AIR-Q laryngeal mask airway: A case report

BACKGROUND

The airways of patients undergoing awake craniotomy (AC) are considered “predicted difficult airways”, inclined to be managed with supraglottic airway devices (SADs) to lower the risk of coughing or gagging. However, the special requirements of AC in the head and neck position may deteriorate SADs’ seal performance, which increases the risks of ventilation failure, severe gastric insufflation, regurgitation, and aspiration.

CASE SUMMARY

A 41-year-old man scheduled for AC with the asleep–awake–asleep approach was anesthetized and ventilated with a size 3.5 AIR-Q intubating laryngeal mask airway (LMA). Air leak was noticed with adequate ventilation after head rotation for allowing scalp blockage. Twenty-five minutes later, the LMA was replaced by an endotracheal tube because of a change in the surgical plan. After surgery, the patient consistently showed low tidal volume and was diagnosed with gastric insufflation and atelectasis using computed tomography.

CONCLUSION

This case highlights head rotation may cause gas leakage, severe gastric insufflation, and consequent atelectasis during ventilation with an AIR-Q intubating laryngeal airway.

An Update of Neuroanesthesia for Intraoperative Brain Mapping Craniotomy

The perioperative multidisciplinary team approach has probably been best exemplified by the care of awake craniotomy patients. Advancement in anesthesia and meticulous perioperative care has supported the safety and complexity of the surgical and mapping efforts in glioma resection. The discussions in this review will emphasize on anesthetic and perioperative management strategies to prevent complications and minimize their effects if they occur, including current practice guidelines in anesthesia, updates on the applications of anesthetic medications, and emerging devices. Planning the anesthetic and perioperative management is based on understanding the pharmacology of the medications, the goals of different stages of the surgery and mapping, and anticipating potential problems.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Emergency Airway Management During Awake Craniotomy: Comparison of 5 Techniques in a Cadaveric Model

BACKGROUND

During awake craniotomy, securing the patient's airway might be necessary electively or emergently. The objective of this study was to compare the feasibility of airway management using a laryngeal mask airway (LMA) and 4 alternative airway management techniques in an awake craniotomy simulation.

METHODS

After completing a questionnaire, 9 anesthesia providers attempted airway management in a cadaver positioned to simulate awake craniotomy conditions. Following the simulation, participants rated and ranked the devices in their order of preference.

RESULTS

Only 3 approaches resulted in the successful securement of an airway device for 100% of participants: LMA (median; interquartile range time to secure the airway 6 s, 5 to 10 s), fiberoptic bronchoscopy through an LMA (41 s; 23 to 51 s), and video laryngoscopy (49 s; 43 to 127 s). In contrast, the oral and nasal fiberoptic approaches demonstrated only 44.4% (154.5 s; 134.25 to 182 s) and 55.6% (75 s; 50 to 117 s) success rates, respectively. The LMA was the fastest and most reliable primary method to secure the airway (P=0.001). After the simulation, 100% of participants reported that an LMA would be their first choice for emergency airway management, followed by fiberoptic intubation through the LMA (7 of 9 participants) if the LMA failed to properly seat.

CONCLUSIONS

We demonstrated that an LMA was the fastest and most reliable primary method to secure an airway in a laterally positioned cadaver with 3-pin skull fixation. Fiberoptic and video laryngoscope airway equipment should be readily available during awake craniotomy procedures, and an attempt to visualize the vocal cords through the LMA should be attempted before removing it for alternative techniques.