A spray-as-you-go airway topical anesthesia attenuates cardiovascular responses for double-lumen tube tracheal intubation

Guideline recommendations on the assessment and management of awake airway intubation: a systematic review

OBJECTIVES

To systematically appraise the quality of clinical practice guidelines (CPGs) regarding awake tracheal intubation (ATI) and to compare the consistency of common recommendations.

DESIGN

Systematic review, critical appraisal and narrative synthesis of CPG recommendations for ATI.

METHODS

A systematic search of the PubMed, EMBASE, Cochrane, Web of Science, and Scopus databases was conducted up to July 1, 2024, to identify up-to-date CPGs. The AGREE II (Appraisal of Guidelines for Research and Evaluation) checklist was used to critically appraise the CPGs. Interrater agreement was determined via intraclass correlation coefficients (ICCs) with a two-way random effects model for each domain and overall rating score. All the suggestions extracted from the included guidelines were sorted and analyzed and summarized via the GRADE (Grading of Recommendations Assessment, Development and Evaluation) system.

RESULTS

Our study resulted in 939 records and ultimately 7 CPGs were appraised. The content of these CPGs covered six themes of ATI: indications, airway local anesthesia, the intubation procedure, checking the tube position, management after ATI failure, and the extubation process. When the AGREE II tool was used to appraise CPGs, only 3 CPGs were rated as "high" quality. With the exception of domain 1, we observed good agreement in all five other domains (ICCs over 0.7). These CPGs provided relatively consistent recommendations and evidence on intubation procedures and checking tube position. In terms of indications and airway local anesthesia, there was controversy. Twenty-nine recommendations regarding ATI were summarized through the GRADE system, among which 16 were considered relatively reliable.

CONCLUSION

Through the AGREE II tool and the GRADE system, the strengths and weaknesses of each CPG were comprehensively analyzed on the basis of its scientific validity and practicability. Moreover, the limitations of the current CPGs in terms of indications, airway local anesthesia and complex clinical situations are presented, and clinicians are encouraged to apply the guidelines more scientifically and to update and improve the guidelines.

SYSTEMATIC REVIEW REGISTRATION

CRD4202458548 (PROSPERO).

Ultrasound-guided superior laryngeal nerve block: a randomized comparison between parasagittal and transverse approach

BACKGROUND

Different approach ultrasound-guided superior laryngeal nerve block was used to aid awake intubation, but little is known which approach was superior. We aimed to compare the parasagittal and transverse approaches for ultrasound-guided superior laryngeal nerve block in adult patients undergoing awake intubation.

METHODS

Fifty patients with awake orotracheal intubation were randomized to receive either a parasagittal or transverse ultrasound-guided superior laryngeal nerve block. The primary outcome was patient's quality of airway anesthesia grade during insertion of the tube into the trachea. The patients' tube tolerance score after intubation, total procedure time, mean arterial pressure, heart rate, Ramsay sedation score at each time point, incidence of sore throat both 1 h and 24 h after extubation, and hoarseness before intubation, 1 h and 24 h after extubation were documented.

RESULTS

Patients' quality of airway anesthesia was significantly better in the parasagittal group than in the transverse group (median grade[IQR], 0 [0-1] vs. 1 [0-1], P = 0.036). Patients in the parasagittal approach group had better tube tolerance scores (median score [IQR],1[1-1] vs. 1 [1-1.5], P = 0.042) and shorter total procedure time (median time [IQR], 113 s [98.5-125.5] vs. 188 s [149.5-260], P < 0.001) than those in the transverse approach group. The incidence of sore throat 24 h after extubation was lower in the parasagittal group (8% vs. 36%, P = 0.041). Hoarseness occurred in more than half of the patients in parasagittal group before intubation (72% vs. 40%, P = 0.023).

CONCLUSIONS

Compared to the transverse approach, the ultrasound-guided parasagittal approach showed improved efficacy in terms of the quality of airway topical anesthesia and shorter total procedure time for superior laryngeal nerve block.

TRIAL REGISTRATION

This prospective, randomized controlled trial was approved by the Ethics Committee of Nanjing First Hospital (KY20220425-014) and registered in the Chinese Clinical Trial Registry (19/6/2022, ChiCTR2200061287) prior to patient enrollment. Written informed consent was obtained from all participants in this trial.

Negative-Pressure Pulmonary Edema Induced by Flexible Bronchoscopy: A Case Report

Negative-pressure pulmonary edema (NPPE) arises from excessive inspiratory effort due to upper airway obstruction, often associated with postoperative laryngospasm and upper airway infections like epiglottitis. We present a case of NPPE during bronchoscopy. A 45-year-old female patient, who was undergoing bronchoscopy for interstitial pneumonia evaluation, was examined using a tracheal tube with a 7.5 mm internal diameter and a bronchoscope with a 5.9 mm external diameter. The patient's respiratory condition gradually worsened after intubation. We continued with the examination, supplying approximately 5 L/min of oxygen through the intubation tube. We performed an alveolar lavage, and the recovered fluid gradually turned pale and bloody. After the examination, the patient continued to expectorate pink and frothy sputum and prolonged respiratory failure. Chest radiography revealed new extensive bilateral infiltrates. We ruled out cardiogenic causes through clinical examination, electrocardiogram (ECG), and transthoracic echocardiography. As a result, we suspected that temporary upper airway obstruction during bronchoscopy led to NPPE. Applying continuous positive airway pressure (CPAP) quickly improved the pulmonary edema. The risk of NPPE during bronchoscopy needs to be acknowledged, especially when using larger bronchoscopes and smaller tracheal tubes.

Effect of pre-use of Dexmedetomidine on the effective inhibitory dose of remimazolam tosilate on positive cardiovascular response in double-lumen endobronchial intubation: a clinical study

BACKGROUND

Herein, the effect of pre-use of Dexmedetomidine(Dex) on the half-effective dose (ED50) and 95%-effective dose (ED95) of Remimazolam tosilate(RT) in inhibiting the positive cardiovascular response(CR) which means blood pressure or heart rate rises above a critical threshold induced by double-lumen bronchial intubation was evaluated.

METHODS

Patients who underwent video-assisted thoracic surgery were divided into groups A (0), B (0.5 µg/kg), and C (1 µg/kg) based on different Dex doses. Group A included subgroups comprising young (A-Y) and elderly (A-O) patients. Neither groups B nor C included elderly patients due of the sedative effect of Dex. Based on the previous subject's CR, the dose of RT was increased or decreased in the next patient using the sequential method. This trial would be terminated when the seventh crossover occurred, at which point the sample size met the stable estimate of the target dose. Heart rate (HR) and mean arterial pressure (MAP) were monitored throughout the trial, and sedation was assessed using the Modified Observer's Assessment of Alertness/Sedation (MOAA/S) scale. HR and MAP were recorded at baseline (T1), the end of Dex (T2), and the end of RT (T3), the maximum HR and MAP were recorded within 3 min of intubation from beginning to end (T4). There was a positive CR when the T4 levels rose above 15% of the baseline. The ED50/ED95 and corresponding confidence interval were calculated using probability regression.

RESULTS

In total, 114 patients completed the trial. Without the use of Dex, the ED50/ED95 of TR inhibiting the positive CR caused by double-lumen bronchial intubation was 0.198/0.227 and 0.155/0.181 mg/kg in groups A-Y and A-O, respectively. The changes in vital signs from T1 to T3 were similar in the subgroups, indicating that the elderly patients were more sensitive to the dose of RT. The ED50/ED95 of RT inhibiting the positive CR caused by double-lumen endobronchial intubation was 0.122/0.150 and 0.068/0.084 mg/kg in groups B and C, respectively. And, the fluctuation of blood pressure from T3 to T4 was reduced by using Dex. RT was 100% effective in sedation with no significant inhibition of circulation. Apart from one case of hypotension occurred in group A-Y, two cases of low HR in group B, and one case of low HR in group C, no other adverse events were noted.

CONCLUSIONS

The optimal dose of RT to inhibit positive CR induced by double-lumen bronchial intubation in elderly patients was 0.18 mg/kg and 0.23 mg/kg in younger patients. When the pre-use dose of Dex was 0.5 µg/kg, the optimal dose to inhibit positive CR of RT was 0.15 mg/kg. And, when the pre-use dose of Dex was 1 µg/kg, the optimal dose of RT was 0.9 mg/kg.

CLINICAL TRIAL REGISTRATION

NCT05631028.

Effects of right stellate ganglion block combined with topical anesthesia on heart rate variability in awake patients receiving tracheal intubation

Objective

General anesthesia is commonly performed with tracheal intubation. We aimed to evaluate the effects of right stellate ganglion block combined with topical anesthesia on the heart rate variability in awake patients receiving tracheal intubation.

Methods

A total of 120 eligible patients were equally divided into observation and control groups using a random number table. The observation group underwent right stellate ganglion block combined with topical anesthesia. The excellent and good rate of anesthesia, indicators of vital signs and heart rate variability, incidence rate of adverse reactions, success rate and time consumption of tracheal intubation, postoperative resuscitation and cognitive function score of the two groups were compared.

Results

The systolic pressure, diastolic pressure and heart rate significantly increased in both groups during tracheal intubation compared with those before tracheal intubation, which they were lower in the observation group than those in the control group during tracheal intubation (P<0.05). Low-frequency power, ratio of low-frequency power to high-frequency power and heart rate variability index significantly decreased in both groups during tracheal intubation compared with those before tracheal intubation (P<0.05).

Conclusion

Right stellate ganglion block combined with topical anesthesia can work well for awake patients during tracheal intubation.

Airway nerve blocks for awake tracheal intubation: A meta-analysis of randomized control trials and trial sequential analysis

STUDY OBJECTIVE

This systematic review and meta-analysis aimed to assess the superiority of airway nerve blocks versus airway anesthesia without nerve blocks for awake tracheal intubation (ATI).

DESIGN

Systematic review and meta-analysis of randomized controlled trials (RCTs).

SETTING

All studies that assessed the superiority of airway anesthesia technique for awake tracheal intubation were searched in PubMed, Web of Science, Cochrane Library, Ovid Medline, Embase and Chinese databases (including China National Knowledge Infrastructure, Wanfang database, and VIP databases) and trial registry databases from their inception to December 2022.

PATIENTS

Adult patients included in randomized controlled trials comparing airway anesthesia with or without airway nerve blocks for ATI.

INTERVENTIONS

Airway nerve (including superior laryngeal nerve, glossopharyngeal nerve, or recurrent laryngeal nerve) blocks for ATI.

MEASUREMENTS

The primary outcome was the intubation time. Secondary outcomes were quality of intubating conditions (including patient reaction to placement of the flexible scope and tracheal tube, coughing and gagging, and patient satisfaction) and overall complications during ATI.

MAIN RESULTS

Fourteen articles with 658 patients were identified for analysis. When compared with airway anesthesia without nerve blocks, airway nerve blocks significantly reduced intubation time (standardized mean difference [SMD] -2.57, 95% CI -3.59- -1.56, p < 0.00001), improved anesthesia quality of ATI with higher no reaction to placement of the flexible scope and tracheal tube (relative risk [RR] 9.87; 95% CI 4.10-23.75, p < 0.00001), lower cough or gag reflex during intubation (RR 0.35, 95% CI 0.27-0.46, p < 0.00001), higher excellent patient satisfaction rate (RR 1.88, 95% CI 1.05-3.34, p = 0.03), and lower overall complications (RR 0.29, 95% CI 0.19-0.45, p < 0.00001). The overall quality of evidence was moderate.

CONCLUSIONS

Based on current published evidence, airway nerve blocks provide better airway anesthesia quality for ATI with a shorter intubation time, better intubation conditions including higher no reaction to placement of the flexible scope and tracheal tube, lower cough or gag reflex during intubation, higher excellent patient satisfaction, and lower overall complications.