Randomized Trial Comparing Early and Late Administration of Rocuronium Before and After Checking Mask Ventilation in Patients With Normal Airways

Facemask ventilation and vocal cord angle following neuromuscular blockade: a prospective observational study. Anaesthesia 2022;77:1010-1017. [PMID: 35727620 DOI: 10.1111/anae.15786]

Numerous studies support the idea that neuromuscular blockade facilitates facemask ventilation after induction of anaesthesia. Although improved airway patency or pulmonary compliance and a resolution of laryngospasm have been suggested as possible causes, the exact mechanism remains unclear. We aimed to assess whether neuromuscular blockade improves facemask ventilation and to clarify whether this phenomenon is associated with the vocal cord angle. This prospective observational study included patients aged between 20 and 65 years scheduled for elective surgery under general anaesthesia. After induction of anaesthesia, patients' lungs were ventilated with pressure-controlled ventilation using a facemask. During facemask ventilation, a flexible bronchoscope was inserted through a self-sealing diaphragm at the elbow connector attached to the facemask and breathing circuit and positioned to allow a continuous view of the vocal cords. The mean tidal volume and vocal cord angle were measured before and after administration of neuromuscular blocking drugs. Of 108 patients, 100 completed the study. Mean (SD) tidal volume ((11.0 (3.9) ml.kg^-1 vs. 13.6 (2.6) ml.kg^-1 ; p < 0.001) and mean (SD) vocal cord angle (17° (10°) vs. 26° (5°); p < 0.001) increased significantly after neuromuscular blockade. The proportional increase in mean tidal volume after neuromuscular blockade was positively correlated with vocal cord angle (Spearman's ρ = 0.803; p < 0.001). In conclusion, neuromuscular blockade facilitated facemask ventilation, and the improvement was correlated with further opening of the vocal cords.

Rocuronium versus saline for effective facemask ventilation during anesthesia induction: a double-blinded randomized placebo-controlled trial

Background

Mask ventilation progressively improves after loss of consciousness during anesthesia induction possibly due to progression of muscle paralysis. This double-blinded randomized placebo-controlled study aimed to test a hypothesis that muscle paralysis improves mask ventilation during anesthesia induction.

Methods

Forty-four adults patients including moderate to severe obstructive sleep apnea undergoing scheduled surgeries under elective general anesthesia participated in this study. Randomly-determined test drug either rocuronium or saline was blinded to the patient and anesthesia provider. One-handed mask ventilation with an anesthesia ventilator providing a constant driving pressure and respiratory rate (15 breaths per minute) was performed during anesthesia induction, and changes of capnogram waveform and tidal volume were assessed for one minute. The needed breaths for achieving plateaued-capnogram (primary variable) within 15 consecutive breaths were compared between the test drugs.

Results

Measurements were successful in 38 participants. Twenty-one and seventeen patients were allocated into saline and rocuronium respectively. The number of breaths achieving plateaued capnogram did not differ between the saline (95% C.I.: 6.2 to 12.8 breaths) and rocuronium groups (95% C.I.: 5.6 to 12.7 breaths) (p = 0.779). Mean tidal volume changes from breath 1 was significantly greater in rocuronium group than saline group (95% C.I.: 0.56 to 0.99 versus 3.51 to 4.53 ml kg-IBW−1, p = 0.006). Significantly more patients in rocuronium group (94%) achieved tidal volume greater than 5 mg kg-ideal body weight−1 within one minute than those in saline group (62%) (p = 0.026). Presence of obstructive sleep apnea did not affect effectiveness of rocuronium for improvement of tidal volume during one-handed mask ventilation.

Conclusions

Use of rocuronium facilitates tidal volume improvement during one-handed mask ventilation even in patients with moderate to severe obstructive sleep apnea.

Trial registration

The clinical trial was registered at (05/12/2013, UMIN000012495): https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000014515

General anesthetic techniques for enhanced recovery after surgery: Current controversies

General anesthesia technique can influence not only immediate postoperative outcomes, but also long-term outcomes beyond hospital stay (e.g., readmission after discharge from hospital). There is lack of evidence regarding superiority of total intravenous anesthesia over inhalation anesthesia with regards to postoperative outcomes even in high-risk population including cancer patients. Optimal balanced general anesthetic technique for enhance recovery after elective surgery in adults includes avoidance of routine use preoperative midazolam, avoidance of deep anesthesia, use of opioid-sparing approach, and minimization of neuromuscular blocking agents and appropriate reversal of residual paralysis. Given that the residual effects of drugs used during anesthesia can increase postoperative morbidity and delay recovery, it is prudent to use a minimal number of drug combinations, and the drugs used are shorter-acting and administered at the lowest possible dose. It is imperative that the discerning anesthesiologist consider whether each drug used is really necessary for accomplishing perioperative goals.

Ease of Application of Various Neuromuscular Devices for Routine Monitoring

BACKGROUND

Subjective evaluations to confirm recovery from neuromuscular blockade with a peripheral nerve stimulator (PNS) is inadequate. Quantitative monitors are the only reliable method to confirm adequate recovery of neuromuscular function. Unfortunately, many clinicians are unfamiliar with such devices and there is concern that the introduction of objective monitoring would be exceedingly laborious and could cause workflow delays. This study investigates how long it takes experienced nurse anesthetists to apply various neuromuscular devices as well as their perception regarding the ease of application.

METHODS

Twenty nurse anesthetists were consented and participated in an educational session that familiarized them with 3 devices: SunStim Plus PNS (SunMed, Grand Rapids, MI), the acceleromyography-based IntelliVue NMT device (Philips, Amsterdam, the Netherlands), and electromyography-based TetraGraph device (Senzime B.V., Uppsala, Sweden). Participants were timed while placing each monitor on patients in a real-world setting. For the quantitative devices (IntelliVue NMT and TetraGraph), participants were also timed when obtaining calibrated baseline train-of-four (TOF) ratios. Friedman test and pairwise Wilcoxon signed-rank tests were used to evaluate the difference in time to connect different devices. Participants were surveyed about how easy they found it to utilize these devices.

RESULTS

After adjusting for multiple comparison, time to connect was significantly less for PNS (median, 29; range, 16-58 seconds) compared to either the TetraGraph device (median, 62.8; range, 32-101 seconds; P < .001) or the IntelliVue NMT device (median, 46; range: 28-90 seconds; P < .001). The difference in time to connect between the TetraGraph device and the IntelliVue NMT device was not statistically significant (P = .053), but it took significantly less time to calibrate the TetraGraph device than the IntelliVue NMT device (median difference, -16; range, -88 to 49 seconds; P = .002). The participants found applying either the IntelliVue NMT device (P = .042) or the TetraGraph device (P = .048) more difficult than applying a PNS while finding it easier to calibrate the TetraGraph device versus the IntelliVue NMT device (P < .001).

CONCLUSIONS

It takes 19 seconds longer to apply a quantitative neuromuscular monitor (the IntelliVue NMT device) than a PNS. While this difference reached significance, this relatively minimal additional time represents an inappropriate barrier to the application of quantitative monitors. Regardless of which quantitative monitor was utilized, these nurse anesthetists found the application and utilization of such devices relatively straightforward.

Macintosh Videolaryngoscope for Intubation in the Operating Room: A Comparative Quality Improvement Project

BACKGROUND

"Macintosh"-videolaryngoscopes (VLs) are VLs that allow both direct and indirect laryngoscopy for intubation. We describe the decision-making and implementation-processes that our hospital used regarding the choice of device. We compared the performances of 4 Macintosh-VLs both in direct and indirect laryngoscopy.

METHODS

A quality-improvement-project for airway management aiming at implementing Macintosh-VL for all intubation procedures performed in the operating room, involving 4 Macintosh-VLs (McGrath-Mac, C-MAC-S, C-MAC-S-Pocket-Monitor [PM], and APA). Three consecutive steps were described: (1) direct laryngoscopy with Macintosh-VL, (2) indirect laryngoscopy with Macintosh-VL (intubation attempt with Macintosh-style blade in case of Cormack I or II), (3) intubation attempt with hyperangulated blade in case of Cormack III/IV or failure of Macintosh-style blade. The main end point was the need to move to step III and use a hyperangulated blade. A mixed-effects multivariable logistic regression analysis was performed to compare devices on the main end point while considering site as a random effect. Comparison of means was performed using analysis of variance and Tukey's test for multiple comparisons (number of laryngoscopy attempts, numeric rate scale [NRS] difficulty of intubation and NRS user-friendliness). Comparison of percentages was performed using a χ2 test for the need to move to step III and a Kruskal-Wallis test for the quality of image (bad, passable, good, very good, excellent). A P value ≤.008 was considered statistically significant.

RESULTS

From May to September 2017, 589 patients were included. Using the McGrath-Mac (22/180 [12%]) was associated with less use of hyperangulated blade than using the C-MAC-S (39/132 [30%], odds ratio [OR] [99.2% confidence interval {CI}] 0.34 [0.16-0.77], P = .0005), the APA (35/138 [25%], OR [99.2% CI] 0.42 [0.19-0.93]; P = .004), but not the C-MAC-S-PM (29/139 [21%], OR [99.2% CI] 0.53 [0.23-1.2]; P = .04).Overall, the number of intubation attempts was significantly lower using the McGrath Mac than the C-MAC-S or the C-MAC-S-PMVLs. Subjective appreciation of intubation difficulty and user-friendliness of the devices showed respectively lower and higher NRS scores for the McGrath-Mac compared to the other devices, whereas subjective assessment of image quality showed higher quality for the C-MAC-S and C-MAC-S-PM compared to the APA or McGrath-Mac.

CONCLUSIONS

Among 4 single-use Macintosh-VLs, glottic visualization in direct and indirect laryngoscopy with the Macintosh-style blade was significantly improved with the McGrath-Mac compared to other Macintosh-VLs, leading to a less frequent need to resort to the hyperangulated blade and reduced overall number of intubation attempts.

Canadian Airway Focus Group updated consensus-based recommendations for management of the difficult airway: part 2. Planning and implementing safe management of the patient with an anticipated difficult airway

PURPOSE

Since the last Canadian Airway Focus Group (CAFG) guidelines were published in 2013, the published airway management literature has expanded substantially. The CAFG therefore re-convened to examine this literature and update practice recommendations. This second of two articles addresses airway evaluation, decision-making, and safe implementation of an airway management strategy when difficulty is anticipated.

SOURCE

Canadian Airway Focus Group members, including anesthesia, emergency medicine, and critical care physicians were assigned topics to search. Searches were run in the Medline, EMBASE, Cochrane Central Register of Controlled Trials, and CINAHL databases. Results were presented to the group and discussed during video conferences every two weeks from April 2018 to July 2020. These CAFG recommendations are based on the best available published evidence. Where high-quality evidence is lacking, statements are based on group consensus.

FINDINGS AND KEY RECOMMENDATIONS

Prior to airway management, a documented strategy should be formulated for every patient, based on airway evaluation. Bedside examination should seek predictors of difficulty with face-mask ventilation (FMV), tracheal intubation using video- or direct laryngoscopy (VL or DL), supraglottic airway use, as well as emergency front of neck airway access. Patient physiology and contextual issues should also be assessed. Predicted difficulty should prompt careful decision-making on how most safely to proceed with airway management. Awake tracheal intubation may provide an extra margin of safety when impossible VL or DL is predicted, when difficulty is predicted with more than one mode of airway management (e.g., tracheal intubation and FMV), or when predicted difficulty coincides with significant physiologic or contextual issues. If managing the patient after the induction of general anesthesia despite predicted difficulty, team briefing should include triggers for moving from one technique to the next, expert assistance should be sourced, and required equipment should be present. Unanticipated difficulty with airway management can always occur, so the airway manager should have a strategy for difficulty occurring in every patient, and the institution must make difficult airway equipment readily available. Tracheal extubation of the at-risk patient must also be carefully planned, including assessment of the patient's tolerance for withdrawal of airway support and whether re-intubation might be difficult.

The Year in Cardiothoracic Critical Care: Selected Highlights from 2019

In 2019, cardiothoracic and vascular critical care remained an important focus and subspecialty. This article continues the annual series to review relevant contributions in postoperative critical care that may affect the cardiac anesthesiologist. Herein, the pertinent literature published in 2019 is explored and organized by organ system.

Emergent airway management of the critically ill patient: current opinion in critical care

PURPOSE OF REVIEW

To describe techniques to facilitate safe intubation in critically ill patients.

RECENT FINDINGS

Despite advances in the treatment of critically ill patients, endotracheal intubation remains a high-risk procedure associated with complications that can lead to appreciable morbidity and mortality. In addition to the usual anatomical factors that can predict a difficult intubation, incorporating pathophysiological considerations and crisis resource management may enhance safety and mitigate risk. Enhancing preoxygenation with high-flow oxygen or noninvasive ventilation, the early use of intravenous fluids and/or vasopressors to prevent hypotension and videolaryngoscopy for first pass success are all promising additions to airway management.Facilitating intubation by either sedation with paralysis or allowing patients to continue to breathe spontaneously are reasonable options for airway management. These approaches have potential advantages and disadvantages.

SUMMARY

Recognizing the unique challenges of endotracheal intubation in critically ill patients is paramount in limiting further deterioration during this high-risk procedure. A safe approach to intubation focuses on recognizing risk factors that predict challenges in achieving an optimal view of the glottis, maintaining optimal oxygenation, and minimizing the risks and benefits of sedation/induction strategies that are meant to facilitate intubation and avoid clinical deterioration.

How to optimize neuromuscular blockade in ambulatory setting?

PURPOSE OF REVIEW

The purpose of this review is to discuss the optimal use of neuromuscular blocking agents (NMBA) during ambulatory surgery, and to provide an update on the routine use of neuromuscular monitoring and the prevention of residual paralysis.

RECENT FINDINGS

The number of major surgical procedures performed in ambulatory patients is likely to increase in the coming years, following the development of laparoscopic and thoracoscopic procedures. To successfully complete these procedures, the proper use of NMBA is mandatory. The use of NMBA not only improves intubating conditions but also ventilation. Recent studies demonstrate that NMBA are much more the solution rather than the cause of airway problems. There is growing evidence that the paralysis of the diaphragm and the abdominal wall muscles, which are resistant to NMBA is of importance during laparoscopic surgery. Further studies are still required to determine when deep neuromuscular block [posttetanic count (PTC) < 5] is required perioperatively. There is now a consensus to use perioperatively neuromuscular monitoring and particularly objective neuromuscular monitoring in combination with reversal agents to avoid residual paralysis and its related morbidity (e.g. respiratory complications in the PACU).

SUMMARY

Recent data suggest that it is now possible to obtain a tight control of neuromuscular block to maintain optimal relaxation tailored to the surgical requirements and to obtain a rapid and reliable recovery at the end of the procedure.

Checking mask ventilation before neuromuscular block: A nation-wide survey of anaesthetists' attitudes and thinking

BACKGROUND

The value of checking mask ventilation before administering neuromuscular blocking drugs is still debated.

METHOD

We conducted a survey of the practice of anaesthetists in Sweden, first asking if they use a mask ventilation trial (MVT) as part of routine induction with intubation (not rapid sequence induction or expected difficult airway). We focused on the reasons for or against the MVT, probing the anaesthetists' attitudes in general but also in specific scenarios.

RESULTS

The response rate was 54%. We found that 65.1% routinely use a MVT, 21.4% sometimes do and 13.5% never do so. There was no effect for years of experience on the distribution. The most common reason for checking mask ventilation was "to gather information about the airway," while the reason for not using the MVT was mostly "that muscle relaxation often improves mask ventilation."

CONCLUSION

We found several interesting comments about airway management at both practical and theoretical levels. The survey highlights that routinely performing a MVT is a common practice in Sweden in spite of the lack of evidence for increased patient safety. Future airway guidelines may need to address this practice.