Effect of Cricoid Pressure Compared With a Sham Procedure in the Rapid Sequence Induction of Anesthesia: The IRIS Randomized Clinical Trial

Preoperative fasting and the risk of pulmonary aspiration-a narrative review of historical concepts, physiological effects, and new perspectives

In the early days of anaesthesia, the fasting period for liquids was kept short. By the mid-20th century 'nil by mouth after midnight' had become routine as the principles of the management of 'full stomach' emergencies were extended to include elective healthy patients. Back then, no distinction was made between the withholding of liquids and solids. Towards the end of the last century, recommendations of professional anaesthesiology bodies began to reduce the fasting time of clear liquids to 2 h. This reduction in fasting time was based on the understanding that gastric emptying of clear liquids is rapid, exponential, and proportional to the current filling state of the stomach. Furthermore, there was no evidence of a link between drinking clear liquids and the risk of aspiration. Indeed, most instances of aspiration are caused by failure to identify aspiration risk factors and adjust the anaesthetic technique accordingly. In contrast, long periods of liquid withdrawal cause discomfort and may also lead to serious postoperative complications. Despite this, more than two decades after the introduction of the 2 h limit, patients still fast for a median of up to 12 h before anaesthesia, mainly because of organisational issues. Therefore, some hospitals have decided to allow patients to drink clear liquids within 2 h of induction of anaesthesia. Well-designed clinical trials should investigate whether these concepts are safe in patients scheduled for anaesthesia or procedural sedation, focusing on both aspiration risk and complications of prolonged fasting.

Spanish Society of Anesthesiology, Reanimation and Pain Therapy (SEDAR), Spanish Society of Emergency and Emergency Medicine (SEMES) and Spanish Society of Otolaryngology, Head and Neck Surgery (SEORL-CCC) Guideline for difficult airway management. Part I

The Airway Management section of the Spanish Society of Anesthesiology, Resuscitation, and Pain Therapy (SEDAR), the Spanish Society of Emergency Medicine (SEMES), and the Spanish Society of Otorhinolaryngology and Head and Neck Surgery (SEORL-CCC) present the Guide for the comprehensive management of difficult airway in adult patients. Its principles are focused on the human factors, cognitive processes for decision-making in critical situations, and optimization in the progression of strategies application to preserve adequate alveolar oxygenation in order to enhance safety and the quality of care. The document provides evidence-based recommendations, theoretical-educational tools, and implementation tools, mainly cognitive aids, applicable to airway management in the fields of anesthesiology, critical care, emergencies, and prehospital medicine. For this purpose, an extensive literature search was conducted following PRISMA-R guidelines and was analyzed using the GRADE methodology. Recommendations were formulated according to the GRADE methodology. Recommendations for sections with low-quality evidence were based on expert opinion through consensus reached via a Delphi questionnaire.

Trauma Anesthesiology Perioperative Management Update

Anesthesia for patients with life-threatening injuries is an essential part of post-accident care. Unfortunately, there is variability in trauma anesthesia care and numerous nonstandardized methods of working with patients remain. Uncertainty exists as to when and how best to intubate trauma patients, the use of vasopressors, and the appropriate management of severe traumatic brain injury. Some physicians recommend prehospital rapid sequence intubation, whereas others use bag-mask ventilation at lower pressures with no cricoid pressure and early transport to a trauma center. Overall, the absence of uniformity in trauma anesthesia care underlines the need for continued study and dialogue to define best practices and optimize patient outcomes.

Effectiveness of the Sellick maneuver for painless gastroscopy in patients with esophageal hiatal hernia: A randomized, self‑control trial

The Sellick maneuver is used for endotracheal intubation to prevent the occurrence of gastroesophageal reflux. The aim of the present study was to observe the effect of the Sellick maneuver on safety, esophageal closure status, gastric mucosal fold extension status, and positive detection rate of lesions in patients with esophageal hiatal hernia under painless gastroscopy. A total of 40 patients with esophageal hiatal hernia who underwent painless gastroscopy were screened for the use of the Sellick maneuver, in which the operator applied pressure to the cervical cricoid cartilage during the examination. The status of esophageal closure at the are pressed, examination time, gastric mucosal fold extension score, positive rate of lesion detection, and reflux of gastric juice or gastric contents, amongst other parameters were assessed. After using the Sellick maneuver, the state of esophageal closure during gastroscopy was significantly better than the no-Sellick maneuver group (P<0.05), and the extension scores of the greater curvature folds of the gastric body, the lateral folds of the lesser curvature of the gastric body, and the mucosal folds of the fundus were significantly higher than that of the no-Sellick maneuver (all P<0.05). The number of gastric polyps and gastric lesions (gastric ulcers and mucosal hyperplasia, amongst others) examined with the Sellick maneuver was significantly higher than the no-Sellick maneuver group (P<0.01). The Sellick maneuver effectively improved the extension of gastric mucosal folds during gastroscopy in patients with esophageal hiatal hernia, increased the positive detection rate of gastric lesions, and shortened the endoscopy time.

Enhancing Patient Safety through Education in a Low-to-Middle-Income Country: Training in the Correct Application of Cricoid Pressure

Background

Cricoid pressure (CP) is applied to occlude the esophagus during endotracheal intubation in patients at an increased risk of aspiration of gastric contents. Evidence shows marked deficiencies in knowledge and skills for CP application among personnel responsible for this task. This study evaluated the effectiveness of CP training in improving knowledge and skills regarding CP application among anesthesiology technicians and critical care nurses and assessed the retention of skills after 2 months.

Methods

Five workshops were conducted on effective application of CP. Indications, relevant anatomy, physiology, and correct technique were taught using interactive sessions and videos and hands-on practice on a weighing scale, 50-mL syringe, and trainer model. Pre- and postworkshop tests were conducted for knowledge and skill. An assessment was repeated after 2 months to assess skill retention.

Results

Five workshops were conducted for 102 participants. Statistically significant improvements were seen in mean scores for knowledge in postworkshop assessments (12.32 ± 2.12 versus 7.12 ± 2.32; P < .01). Similarly, posttraining mean scores for skill assessment were significantly higher than pretraining scores (6.31 ± 0.96 versus 2.72 ± 2.00; P < .0005), indicating an overall 131% improvement. Seventy-four participants appeared for assessment of the retention of skills. A 20% decrement was observed compared with posttraining scores (5.15 ± 1.71 versus 6.45 ± 0.86; P < .0005).

Conclusions

A significant improvement was observed in both knowledge and skills immediately following training. However, this does not ensure long-term retention of clinical skills, as a 20% decrement was observed 2 months after the workshops. Formal training and regular practice are recommended to enable clinicians to perform CP effectively.

Approach to the Physiologically Challenging Endotracheal Intubation in the Intensive Care Unit

Endotracheal intubation for airway management is a common procedure in the ICU. Intubation may be difficult due to anatomic airway abnormalities but also due to physiologic derangements that predispose patients to cardiovascular collapse during the procedure. Results of studies demonstrate a high incidence of morbidity and mortality associated with airway management in the ICU. To reduce the likelihood of complications, medical teams must be well versed in the general principles of intubation and be prepared to manage physiologic derangements while securing the airway. In this review, we present relevant literature on the approach to endotracheal intubation in the ICU and provide pragmatic recommendations relevant to medical teams performing intubations in patients who are physiologically unstable.

Refractory Hyperactive Delirium Without Intravenous Access: A Case Report

Refractory delirium is a complex, often underdiagnosed, and difficult-to-treat phenomenon. It poses significant challenges to healthcare providers, especially in patients without prior intravenous access. In extreme cases, anesthetic management may be needed to treat refractory delirium. Here, we present a unique case of postoperative hyperactive refractory delirium in a patient without intravenous access, ultimately requiring anesthetic management for resolution.

Efficacy of metoclopramide for prevention of gastric regurgitation during endotracheal intubation in the emergency department: A randomized controlled trial

Background

Gastric content regurgitation and aspiration are the dreaded complications of securing the airway. Cricoid pressure hinders intubation and causes lower esophageal sphincter (LES) relaxation. A recent study suggests no added benefit of cricoid pressure in preventing pulmonary aspiration of gastric contents. Metoclopramide increases LES tone, prevents gastroesophageal reflux, and increases antral contractions. Hence, we wanted to study the efficacy of metoclopramide for preventing gastric regurgitation during endotracheal intubation (ETI) in patients presenting to the emergency department (ED).

Methods

This study was a randomized controlled trial in patients requiring ETI in the ED. The study participants were randomized to receive either metoclopramide (intervention) 10 mg/2 ml intravenous (IV) bolus or a placebo of normal saline (placebo) 2 ml IV bolus 5 min before rapid sequence induction and intubation. The outcome of the study was the visualization of gastric regurgitation at the glottic opening during direct laryngoscopy at the time of intubation.

Results

Seventy-four study participants were randomized and allocated to the metoclopramide group (n = 37) or placebo group (n = 37). Gastric regurgitation at the glottis was noted in three study participants (8%) in the metoclopramide group, and six (16%) in the placebo group (odds ratio [OR] - 0.456; 95% confidence interval [CI] of 0.105-1.981; P = 0.295). The study participants who were intubated in the first attempt had less gastric regurgitation compared to ≥2 attempts (OR 0.031; 95% CI of 0.002-0.511; P = 0.015).

Conclusion

There was no decrease in regurgitation with metoclopramide as compared to placebo during ETI in study participants presenting to the ED.

Airway Management of Suspected Traumatic Brain Injury Patients in the Emergency Room

The patients of trauma offers a special challenge because of the associated head injury, maxillofacial, neck and spine injuries, which puts the airway at imminent risk. The response time for the emergency team to initiate the airway management determines the outcome of the individual undergoing treatment. A judious implementatin of triage and ATLS guidelines are helpful in the allocation of resources in airway management of trauma patients. One must not get distracted with the severity of other organ systems because cerebral tissue permits a low threshold to the hypoxic insults. Adequate preparedness and a team effort result in better airway management and improved outcomes in trauma patients with variable hemodynamic response to resuscitation. All possible efforts must be made to secure a definitive airway (if required) and should be verified clinically as well as with the available adjuncts. The success of a trauma team depends on the familiarity to the airways devices and their discrete application in various situations.

Effect of Remifentanil vs Neuromuscular Blockers During Rapid Sequence Intubation on Successful Intubation Without Major Complications Among Patients at Risk of Aspiration: A Randomized Clinical Trial

IMPORTANCE

It is uncertain whether a rapid-onset opioid is noninferior to a rapid-onset neuromuscular blocker during rapid sequence intubation when used in conjunction with a hypnotic agent.

OBJECTIVE

To determine whether remifentanil is noninferior to rapid-onset neuromuscular blockers for rapid sequence intubation.

DESIGN, SETTING, AND PARTICIPANTS

Multicenter, randomized, open-label, noninferiority trial among 1150 adults at risk of aspiration (fasting for <6 hours, bowel occlusion, recent trauma, or severe gastroesophageal reflux) who underwent tracheal intubation in the operating room at 15 hospitals in France from October 2019 to April 2021. Follow-up was completed on May 15, 2021.

INTERVENTIONS

Patients were randomized to receive neuromuscular blockers (1 mg/kg of succinylcholine or rocuronium; n = 575) or remifentanil (3 to 4 μg/kg; n = 575) immediately after injection of a hypnotic.

MAIN OUTCOMES AND MEASURES

The primary outcome was assessed in all randomized patients (as-randomized population) and in all eligible patients who received assigned treatment (per-protocol population). The primary outcome was successful tracheal intubation on the first attempt without major complications, defined as lung aspiration of digestive content, oxygen desaturation, major hemodynamic instability, sustained arrhythmia, cardiac arrest, and severe anaphylactic reaction. The prespecified noninferiority margin was 7.0%.

RESULTS

Among 1150 randomized patients (mean age, 50.7 [SD, 17.4] years; 573 [50%] women), 1130 (98.3%) completed the trial. In the as-randomized population, tracheal intubation on the first attempt without major complications occurred in 374 of 575 patients (66.1%) in the remifentanil group and 408 of 575 (71.6%) in the neuromuscular blocker group (between-group difference adjusted for randomization strata and center, -6.1%; 95% CI, -11.6% to -0.5%; P = .37 for noninferiority), demonstrating inferiority. In the per-protocol population, 374 of 565 patients (66.2%) in the remifentanil group and 403 of 565 (71.3%) in the neuromuscular blocker group had successful intubation without major complications (adjusted difference, -5.7%; 2-sided 95% CI, -11.3% to -0.1%; P = .32 for noninferiority). An adverse event of hemodynamic instability was recorded in 19 of 575 patients (3.3%) with remifentanil and 3 of 575 (0.5%) with neuromuscular blockers (adjusted difference, 2.8%; 95% CI, 1.2%-4.4%).

CONCLUSIONS AND RELEVANCE

Among adults at risk of aspiration during rapid sequence intubation in the operating room, remifentanil, compared with neuromuscular blockers, did not meet the criterion for noninferiority with regard to successful intubation on first attempt without major complications. Although remifentanil was statistically inferior to neuromuscular blockers, the wide confidence interval around the effect estimate remains compatible with noninferiority and limits conclusions about the clinical relevance of the difference.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03960801.

The effect of adding chewing gum to oral carbohydrates on preoperative anxiety scores in women undergoing gynecological surgery: A randomized controlled study

BACKGROUND

Preoperative anxiety is an unpleasant experience that can adversely affect perioperative outcomes. Although clinical benefits of preoperative oral carbohydrate is well reported, the effect of adding chewing gum to carbohydrate loading has never been studied. We aimed to investigate the effect of adding gum-chewing to oral carbohydrates on preoperative anxiety and gastric volume in patients undergoing gynecologic surgery.

METHODS

One hundred and four patients were enrolled and randomized either into a carbohydrate drink group (CHD group) or CHD with gum group. The CHD group was instructed to drink 400 mL of oral carbohydrate the evening before and 200-400 mL 3 hours before surgery. The CHD with gum group was encouraged to chew gum freely during preanesthetic fasting in addition to consuming oral carbohydrates in the same manner. The primary endpoint was preoperative anxiety assessed using the Amsterdam preoperative anxiety and information scale (APAIS). The degree of patient-reported quality of recovery after surgery and gastric volume prior to general anesthesia were also compared as secondary outcomes.

RESULTS

Preoperative APAIS was lower in the CHD with gum group compared with the CHD group (16 [11.5, 20] vs. 20 [16.5, 23], p = 0.008). Patient-rated quality of recovery after surgery was also higher in the CHD with gum group and showed a significant negative correlation with preoperative APAIS score (correlation coefficient: -0.950, p = 0.001). Gastric volume were not different between the groups (0 [0-0.45] vs. 0 [0-0.22], p = 0.158).

CONCLUSION

The addition of gum chewing to oral carbohydrate loading during preoperative fasting was more effective in relieving preoperative anxiety than oral carbohydrate alone in women patients undergoing elective gynecologic surgery.

TRIAL REGISTRATION

Clinical Research Information Services, CRIS identifier: KCT0005714, https://cris.nih.go.kr/cris/index.jsp.

Airway Management in Adult Intensive Care Units: A Survey of Two Regions in China

The critical medicine residency training in China started in 2020, but no investigation on the practice of tracheal intubation in ICUs in China has been conducted. A survey was sent to the adult ICUs in public hospitals in Shenzhen (SZ) city and Xinjiang (XJ) province using a WeChat miniprogram to be completed by intensive care physicians. It included questions on training on intubation, intubation procedures, and changes in the use of personal protective equipment due to COVID-19. We analyzed 301 valid questionnaires which were from 72 hospitals. A total of 37% of respondents had completed training in RSI (SZ, 40% vs. XJ, 30%; $p=0.066$ ), and 50% had participated in a course on the emergency front of the neck airway (SZ, 47% vs. XJ, 54%; $p=0.256$ ). Video laryngoscopy was preferred by 75% of respondents. Manual ventilation (56%) and noninvasive positive pressure ventilation (34%) were the first-line options for preoxygenation. For patients with a high risk of aspiration, nasogastric decompression (47%) and cricoid pressure (37%) were administered. Propofol (82%) and midazolam (70%) were the most commonly used induction agents. Only 19% of respondents routinely used neuromuscular blocking agents. For patients with difficult airways, a flexible endoscope was the most commonly used device by 76% of respondents. Most participants (77%) believed that the COVID-19 pandemic had significantly increased their awareness of the need for personal protective equipment during tracheal intubation. Our survey demonstrated that the ICU doctors in these areas lack adequate training in airway management.

Effectiveness of Cricoid and Paratracheal Pressures in Occluding the Upper Esophagus Through Induction of Anesthesia and Videolaryngoscopy: A Randomized, Crossover Study

BACKGROUND

Maneuvers for preventing passive regurgitation of gastric contents are applied to effectively occlude the esophagus throughout rapid sequence induction and intubation. The aim of this randomized, crossover study was to investigate the effectiveness of cricoid and paratracheal pressures in occluding the esophagus through induction of anesthesia and videolaryngoscopy.

METHODS

After the induction of anesthesia in 40 adult patients, the location of the esophageal entrance relative to the glottis and location of the upper esophagus relative to the trachea at the low paratracheal region were assessed using an ultrasonography, and the outer diameter of the esophagus was measured on ultrasound before and during application of cricoid and paratracheal pressures of 30 N. Then, videolaryngoscopy was performed with the application of each pressure. During videolaryngoscopy, location of the esophageal entrance relative to the glottis under cricoid pressure was examined on the screen of videolaryngoscope, and the upper esophagus under paratracheal pressure was evaluated using ultrasound. The occlusion rate of the esophagus, and the best laryngeal view using the percentage of glottic opening scoring system were also assessed during videolaryngsocopy. Esophageal occlusion under each pressure was determined by inserting an esophageal stethoscope into the esophagus. If the esophageal stethoscope could not be advanced into the esophagus under the application of each pressure, the esophagus was regarded to be occluded.

RESULTS

During videolaryngoscopy, esophagus was occluded in 40 of 40 (100%) patients with cricoid pressure and 23 of 40 (58%) patients with paratracheal pressure (difference, 42%; 95% confidence interval, 26-58; P < .001). Both cricoid and paratracheal pressures significantly decreased the diameter of the esophagus compared to no intervention in the anesthetized paralyzed state ( P < .001, respectively). Ultrasound revealed that the compressed esophagus by paratracheal pressure in the anesthetized paralyzed state was partially released during videolaryngoscopy in 17 of 40 patients, in whom esophageal occlusion was unsuccessful. The best laryngeal view was not significantly different among the no intervention, cricoid pressure, and paratracheal pressure (77 [29] % vs 79 [30] % vs 76 [31] %, respectively; P = .064).

CONCLUSIONS

The occlusion of the upper esophagus defined by inability to pass an esophageal stethoscope was more effective with cricoid pressure than with paratracheal pressure during videolaryngoscopy, although both cricoid and paratracheal pressures reduced the diameter of the esophagus on ultrasound in an anesthetized paralyzed state.

Airway Management of Patients with Suspected or Confirmed COVID-19: Survey Results from Physicians from 19 Countries in Latin America

Airway management during the COVID-19 pandemic has been one of the most challenging aspects of care that anesthesiologists and intensivists face. This study was conducted to evaluate the management of tracheal intubation in patients with suspected or confirmed COVID-19 infection. This is a cross-sectional and international multicenter study based on a 37-item questionnaire. The survey was available to physicians who had performed intubations and tracheostomies in patients with suspected or confirmed COVID-19 and had provided informed consent to participate. The primary outcome is the preference to use a specific device for tracheal intubation. Secondary outcomes are clinical practice variables, use of video laryngoscopes, difficult airway management, and safety features to prevent cross-infection. This study included 2411 physicians who performed an average of 11.90 and 20.67 tracheal intubations in patients diagnosed or suspected of having COVID-19 disease, respectively. Physicians were mainly from the specialties of Anesthesiology (61.2%) and Intensive Care (7.4%). COVID-19 infection diagnosed by positive PCR or serology in physicians participating in intubation in this study was 15.1%. Respondents considered preoxygenation for more than three minutes very useful (75.7%). The preferred device for tracheal intubation was the video laryngoscope (64.8%). However, the direct laryngoscope (57.9%) was the most commonly used, followed by the video laryngoscope (37.5%). The preferred device to facilitate intubation was the Eschmann guide (34.2%). Percutaneous tracheostomy was the preferred technique (39.5%) over the open tracheostomy (22%). The predicted or unpredicted difficult airway management in these patients was preferably performed with a video laryngoscope (61.7% or 63.7, respectively). Intubation was mostly performed by two or more expert airway physicians (61.6%). The use of personal protective equipment increased the practitioners’ discomfort during intubation maneuvers. The video laryngoscope is the preferred device for intubating patients with COVID-19, combined with the Eschmann guide, flexible stylet within the endotracheal tube, or Frova guide to facilitate intubation. The sub-analysis of the two groups of physicians by the level of intubation experience showed a higher use of the video laryngoscope (63.4%) in the experts group and no significant differences between the two groups in terms of cross-infection rates in physicians, in their preference for the use of the video laryngoscope or in the number of intubations performed in confirmed or suspected COVID-19 patients.

Review article: Effectiveness and risks of cricoid pressure during rapid sequence induction for endotracheal intubation in the emergency department: A systematic review

The use of cricoid pressure (CP) to prevent aspiration during rapid sequence induction (RSI) has become controversial, although CP is considered central to the practice of RSI. There is insufficient research to support its efficacy in reducing aspiration, and emerging concerns it reduces the first-pass success (FPS) of intubation. This systematic review aims to assess the safety and efficacy of CP during RSI in EDs by investigating its effect on FPS and the incidence of complications, including gastric regurgitation and aspiration. A systematic review of four databases was performed for all primary research investigating CP during RSI in EDs. The primary outcome was FPS; secondary outcomes included complications such as gastric regurgitation, aspiration, hypoxia, hypotension and oesophageal intubation. After screening 4208 citations, three studies were included: one randomised controlled trial (n = 54) investigating the incidence of aspiration during the application of CP and two registry studies (n = 3710) comparing the rate of FPS of RSI with and without CP. The results of these individual studies are not sufficient to draw concrete conclusions but do suggest that aspiration occurs regardless of the application of CP, and that FPS is not reduced by the application of CP. There is insufficient evidence to conclude whether applying CP during RSI in EDs affects the rate of FPS or the incidence of complications such as aspiration. Further research in the ED, including introducing CP usage into other existing airway registries, is needed.

Tracheal intubation in the critically ill patient

Tracheal intubation is among the most commonly performed and high-risk procedures in critical care. Indeed, 45% of patients undergoing intubation experience at least one major peri-intubation adverse event, with cardiovascular instability being the most common event reported in 43%, followed by severe hypoxemia in 9% and cardiac arrest in 3% of cases. These peri-intubation adverse events may expose patients to a higher risk of 28-day mortality, and they are more frequently observed with an increasing number of attempts to secure the airway. The higher risk of peri-intubation complications in critically ill patients, compared with the anaesthesia setting, is the consequence of their deranged physiology (e.g. underlying respiratory failure, shock and/or acidosis) and, in this regard, airway management in critical care has been defined as "physiologically difficult". In recent years, several randomised studies have investigated the most effective preoxy-genation strategies, and evidence for the use of positive pressure ventilation in moderate-to-severe hypoxemic patients is established. On the other hand, evidence on interventions to mitigate haemodynamic collapse after intubation has been elusive. Airway management in COVID-19 patients is even more challenging because of the additional risk of infection for healthcare workers, which has influenced clinical choices in this patient group. The aim of this review is to provide an update of the evidence for intubation in critically ill patients with a focus on understanding peri-intubation risks and evaluating interventions to prevent or mitigate adverse events.

Anxiolytic effects of chewing gum during preoperative fasting and patient-centered outcome in female patients undergoing elective gynecologic surgery: randomized controlled study

Although previous studies reported that chewing gum during the preoperative fasting has the benefits of alleviating anxiety and dry mouth, preoperative chewing gum has yet to be accepted as a standard practice due to conventional anesthetic custom. Our study aimed to prospectively evaluate the effects of gum chewing on preoperative anxiety and patient's discomfort in female patients undergoing gynecologic surgery. Ninety-four patients were enrolled and randomized either into conventional fasting group (control group) or chewing gum with fasting group (gum group). The control group was instructed to fast from 3 p.m. on the day before surgery. The gum group performed preoperative fasting in the same manner, but was encouraged to chew gum freely during the fasting period. The primary endpoint was the degree of preoperative anxiety. For the evaluation of preoperative anxiety, Amsterdam preoperative anxiety and information scale (APAIS) was used. Preoperative gastric fluid volume and acidity were also measured as the secondary outcomes. Preoperative anxiety using APAIS was significantly lower in the gum group compared to the control group (control group vs. gum group: 20.9 vs. 17.8, p = 0.009). However, there was no significant difference in the gastric fluid analysis between the groups. In the female patients for elective gynecologic surgery, chewing gum during the preoperative fasting period helped to alleviate preoperative anxiety without additional increase of pulmonary aspiration risks.Trial registration: KCT0004422 (05/11/2019, https://cris.nih.go.kr ; registration number).

Airway management of COVID-19 patients: A survey on the experience of 1125 physicians in Spain

BACKGROUND

We explored the experience of clinicians from the Spanish Society of Anesthesiology (SEDAR) in airway management of COVID-19 patients.

METHODS

An software-based survey including a 32-item questionnaire was conducted from April 18 to May 17, 2020. Participants who have been involved in tracheal intubations in patients with suspected or confirmed COVID-19 infection were included anonymously after obtaining their informed consent. The primary outcome was the preferred airway device for tracheal intubation. Secondary outcomes included the variations in clinical practice including the preferred video laryngoscope, plans for difficult airway management, and personal protective equipment.

RESULTS

1125 physicians completed the questionnaire with a response rate of 40,9%. Most participants worked in public hospitals and were anesthesiologists. The preferred device for intubation was the video laryngoscope (5.1/6), with the type of device in decreasing order as follows: Glidescope, C-MAC, Airtraq, McGrath and King Vision. The most frequently used device for intubation was the video laryngoscope (70,5%), using them in descending order as follow: the Airtraq, C-MAC, Glidescope, McGrath and King Vision. Discomfort of intubating wearing personal protective equipment and the frequency of breaching a security step was statistically significant, increasing the risk of cross infection between patients and healthcare workers. The opinion of senior doctors differed from younger physicians in the type of video-laryngoscope used, the number of experts involved in tracheal intubation and the reason that caused more stress during the airway management.

CONCLUSIONS

Most physicians preferred using a video-laryngoscope with remote monitor and disposable Macintosh blade, using the Frova guide.

Rapid sequence induction/intubation controversies

Backgrounds:

Since its first definition and publication on 1970, Rapid Sequence Induction / Intubation (RSI) technique has been accepted globally as the “standard” for doing rapid intubation after induction of anesthesia for patients with high risk of aspiration, especially in emergency situation. However, this technique is not so much a “standard” as there are numerous variations on its practice based on national surveys. Anesthesia providers have their own opinions on the practice of RSI components which need to be discussed to assess their advantages and disadvantages, while there has been no review article which discussed these controversies in the last ten years.

Objectives:

To review the technique differences within RSI protocols.

Methods:

Online databases were searched, including MEDLINE and COCHRANE for each step in the original RSI protocol using keywords such as: “rapid sequence induction” or “rapid sequence intubation” or “RSI” and “controversies” or “head position” or “cricoid pressure” or “neuromuscular blocking agent” or “NMBA” or positive pressure ventilation” or “PPV”; and so on. Articles were then sorted out based on relevancy.

Results and conclusion:

Supported by new evidence, RSI practices may differ in: the positioning of patient, choices of induction agent, application of cricoid pressure, choices of neuromuscular blocking agent, and the use of positive pressure ventilation. A more updated and standardized guideline should be established by referring and evaluating to these controversies.

Emergency Airway Management Outside the Operating Room: Current Evidence and Management Strategies

Emergency airway management outside the operating room (OR) is often associated with an increased risk of airway related, as well as cardiopulmonary, complications which can impact morbidity and mortality. These emergent airways may take place in the intensive care unit (ICU), where patients are critically ill with minimal physiological reserve, or other areas of the hospital where advanced equipment and personnel are often unavailable. As such, emergency airway management outside the OR requires expertise at manipulation of not only the anatomically difficult airway but also the physiologically and situationally difficult airway. Adequate preparation and appropriate use of airway management techniques are important to prevent complications. Judicious utilization of pre- and apneic oxygenation is important as is the choice of medications to facilitate intubation in this at-risk population. Recent study in critically ill patients has shown that postintubation hemodynamic and respiratory compromise is common, independently associated with poor outcomes and can be impacted by the choice of drugs and techniques used. In addition to adequately preparing for a physiologically difficult airway, enhancing the ability to predict an anatomically difficult airway is essential in reducing complication rates. The use of artificial intelligence in the identification of difficult airways has shown promising results and could be of significant advantage in uncooperative patients as well as those with a questionable airway examination. Incorporating this technology and understanding the physiological, anatomical, and logistical challenges may help providers better prepare for managing such precarious airways and lead to successful outcomes. This review discusses the various challenges associated with airway management outside the OR, provides guidance on appropriate preparation, airway management skills, medication use, and highlights the role of a coordinated multidisciplinary approach to out-of-OR airway management.

A way forward in pulmonary aspiration incidence reduction: ultrasound, mathematics, and worldwide data collection

Aspiration of gastric contents during induction of general anesthesia remains a significant cause of mortality and morbidity in anesthesia. Recent data show that pulmonary aspiration still accounts for many cases with implications on mortality despite technical and technological evolution. Practical, ethical, and methodological issues prevent high-quality research in the setting of aspiration and rapid sequence induction/intubation, and significant controversy is ongoing. Patients' position, drugs choice, dosing and timing, use of cricoid force, and a reliable risk assessment are widely debated with significant questions still unanswered. We focus our discussion on three approaches to promote a better understanding of rapid sequence induction/intubation and airway management decision-making. Firstly, we review how we can use qualitative and quantitative assessment of fasting status and gastric content with the point-of-care ultrasound as an integral part of preoperative evaluation and planning. Secondly, we propose using imaging-based mathematical models to study different patient positions and aspiration mechanisms, including identifying aspiration triggers. Thirdly, we promote the development of a global data collection system aiming to obtain precise epidemiological data. Therefore, we fill the gap between evidence-based medicine and experts' opinion through easily accessible and diffused computer-based databases. A better understanding of aspiration epidemiology obtained through focused global data gathering systems, the widespread use of ultrasound-based prandial status evaluation, and development of advanced mathematical models might potentially guide safer airway management decision making in the 21^st century.

Effect of Paratracheal Pressure on the Glottic View During Direct Laryngoscopy: A Randomized Double-Blind, Noninferiority Trial

BACKGROUND

Cricoid pressure has been used as a component of the rapid sequence induction and intubation technique. However, concerns have been raised regarding the effectiveness and safety of cricoid pressure. Paratracheal pressure, a potential alternative to cricoid pressure to prevent regurgitation of gastric contents or aspiration, has been studied to be more effective to cricoid pressure in preventing gastric insufflation during positive pressure ventilation. However, to adopt paratracheal compression into our practice, adverse effects including its effect on the glottic view during direct laryngoscopy should be studied. We conducted a randomized, double-blind, noninferiority trial comparing paratracheal and cricoid pressures for any adverse effects on the view during direct laryngoscopy, together with other secondary outcome measures.

METHODS

In total, 140 adult patients undergoing general anesthesia randomly received paratracheal pressure (paratracheal group) or cricoid pressure (cricoid group) during anesthesia induction. The primary end point was the incidence of deteriorated laryngoscopic view, evaluated by modified Cormack-Lehane grade with a predefined noninferiority margin of 15%. Secondary end points included percentage of glottic opening score, ease of mask ventilation, change in ventilation volume and peak inspiratory pressure during mechanical mask ventilation, ease of tracheal intubation, and resistance encountered while advancing the tube into the glottis. The position of the esophagus was assessed by ultrasound in both groups to determine whether pressure applied to the respective area would be likely to result in esophageal compression. All secondary outcomes were tested for superiority, except percentage of glottic opening score, which was tested for noninferiority.

RESULTS

Paratracheal pressure was noninferior to cricoid pressure regarding the incidence of deterioration of modified Cormack-Lehane grade (0% vs 2.9%; absolute risk difference, -2.9%; 95% confidence interval, -9.9 to 2.6, P <.0001). Mask ventilation, measured on an ordinal scale, was found to be easier (ie, more likely to have a lower score) with paratracheal pressure than with cricoid pressure (OR, 0.41; 95% confidence interval, 0.21-0.79; P = .008). The increase in peak inspiratory pressure was significantly less in the paratracheal group than in the cricoid group during mechanical mask ventilation (median [min, max], 0 [-1, 1] vs 0 [-1, 23]; P = .001). The differences in other secondary outcomes were nonsignificant between the groups. The anatomical position of the esophagus was more suitable for compression in the paratracheal region, compared to the cricoid cartilage region.

CONCLUSIONS

Paratracheal pressure was noninferior to cricoid pressure with respect to the effect on glottic view during direct laryngoscopy.

Pulmonary Aspiration of Gastric Contents: A Closed Claims Analysis

BACKGROUND

Perioperative pulmonary aspiration of gastric contents has been associated with severe morbidity and death. The primary aim of this study was to identify outcomes and patient and process of care risk factors associated with gastric aspiration claims in the Anesthesia Closed Claims Project. The secondary aim was to assess these claims for appropriateness of care. The hypothesis was that these data could suggest opportunities to reduce either the risk or severity of perioperative pulmonary aspiration.

METHODS

Inclusion criteria were anesthesia malpractice claims in the American Society of Anesthesiologists Closed Claims Project that were associated with surgical, procedural, or obstetric anesthesia care with the year of the aspiration event 2000 to 2014. Claims involving pulmonary aspiration were identified and assessed for patient and process factors that may have contributed to the aspiration event and outcome. The standard of care was assessed for each claim.

RESULTS

Aspiration of gastric contents accounted for 115 of the 2,496 (5%) claims in the American Society of Anesthesiologists Closed Claims Project that met inclusion criteria. Death directly related to pulmonary aspiration occurred in 66 of the 115 (57%) aspiration claims. Another 16 of the 115 (14%) claims documented permanent severe injury. Seventy of the 115 (61%) patients who aspirated had either gastrointestinal obstruction or another acute intraabdominal process. Anesthetic management was judged to be substandard in 62 of the 115 (59%) claims.

CONCLUSIONS

Death and permanent severe injury were common outcomes of perioperative pulmonary aspiration of gastric contents in this series of closed anesthesia malpractice claims. The majority of the patients who aspirated had either gastrointestinal obstruction or acute intraabdominal processes. Anesthesia care was frequently judged to be substandard. These findings suggest that clinical practice modifications to preoperative assessment and anesthetic management of patients at risk for pulmonary aspiration may lead to improvement of their perioperative outcomes.

EDITOR’S PERSPECTIVE

Rapid sequence induction: where did the consensus go?

Background

Rapid Sequence Induction (RSI) was introduced to minimise the risk of aspiration of gastric contents during emergency tracheal intubation. It consisted of induction with the use of thiopentone and suxamethonium with the application of cricoid pressure.

This narrative review describes how traditional RSI has been modified in the UK and elsewhere, aiming to deliver safe and effective emergency anaesthesia outside the operating room environment. Most of the key aspects of traditional RSI – training, technique, drugs and equipment have been challenged and often significantly changed since the procedure was first described. Alterations have been made to improve the safety and quality of the intervention while retaining the principles of rapidly securing a definitive airway and avoiding gastric aspiration. RSI is no longer achieved by an anaesthetist alone and can be delivered safely in a variety of settings, including in the pre-hospital environment.

Conclusion

The conduct of RSI in current emergency practice is far removed from the original descriptions of the procedure. Despite this, the principles – rapid delivery of a definitive airway and avoiding aspiration, are still highly relevant and the indications for RSI remain relatively unchanged.

Rapid sequence induction: An international survey

BACKGROUND

Rapid sequence induction (RSI) is a standard procedure, which should be implemented in all patients with a risk of aspiration/regurgitation during anaesthesia induction.

OBJECTIVE

The primary aim was to evaluate clinical practice in RSI, both in adult and paediatric populations.

DESIGN

Online survey.

SETTINGS

A total of 56 countries.

PARTICIPANTS

Members of the European Society of Anaesthesiology.

MAIN OUTCOME MEASURES

The aim was to identify and describe the actual clinical practice of RSI related to general anaesthesia.

RESULTS

From the 1921 respondents, 76.5% (n=1469) were qualified anaesthesiologists. When anaesthetising adults, the majority (61.7%, n=1081) of the respondents preoxygenated patients with 100% O₂ for 3 min and 65.9% (n=1155) administered opioids during RSI. The Sellick manoeuvre was used by 38.5% (n=675) and was not used by 37.4% (n=656) of respondents. First-line medications for a haemodynamically stable adult patient were propofol (90.6%, n=1571) and suxamethonium (56.0%, n=932). Manual ventilation (inspiratory pressure <12 cmH₂O) was used in 35.5% (n=622) of respondents. In the majority of paediatric patients, 3 min of preoxygenation (56.6%, n=817) and opioids (54.9%, n=797) were administered. The Sellick manoeuvre and manual ventilation (inspiratory pressure <12 cmH₂O) in children were used by 23.5% (n=340) and 35.9% (n=517) of respondents, respectively. First-line induction drugs for a haemodynamically stable child were propofol (82.8%, n=1153) and rocuronium (54.7%, n=741).

CONCLUSION

We found significant heterogeneity in the daily clinical practice of RSI. For patient safety, our findings emphasise the need for international RSI guidelines.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT03694860

Airway Management in the Critically Ill Patient

Purpose of Review

This paper will evaluate the recent literature and best practices in airway management in critically ill patients.

Recent Findings

Cardiac arrest remains a common complication of intubation in these high-risk patients. Patients with desaturation or peri-intubation hypotension are at high risk of cardiac arrest, and each of these complications have been reported in up to half of all intubations in critically ill patient populations.

Summary

There have been significant advances in preoxygenation and devices available for performing laryngoscopy and rescue oxygenation. However, the risk of cardiovascular collapse remains concerningly high with few studies to guide therapeutic maneuvers to reduce this risk.

Manejo de vía aérea en pacientes COVID-19: una encuesta sobre la experiencia de 1125 médicos en España

Antecedentes

Analizamos la experiencia de médicos de la Sociedad Española de Anestesiología en el manejo de vía aérea de pacientes COVID-19.

Métodos

Se realizó una encuesta que incluía 32 ítems (18 abril-17 mayo de 2020). Participaron de forma anónima tras aceptar el consentimiento informado médicos involucrados en intubaciones traqueales en pacientes COVID-19 confirmados o con sospecha. El resultado principal fue el dispositivo de vía aérea preferido para la intubación traqueal. Los resultados secundarios incluyeron el análisis de la práctica clínica, el videolaringoscopio preferido, manejo de vía aérea difícil y uso de equipo de protección personal.

Resultados

Completaron el cuestionario 1125 médicos (tasa de respuesta del 40,9%) que eran mayoritariamente anestesiólogos y trabajaban en hospitales públicos.

El dispositivo preferido para intubar fue el videolaringoscopio (5,1/6) con el siguiente orden de preferencia: Glidescope, C-MAC, Airtraq, McGrath y King Vision. El dispositivo de intubación más utilizado fue el videolaringoscopio (70,5%) con el siguiente orden decreciente: Airtraq, C-MAC, Glidescope, McGrath y King Vision.

La relación de incomodidad de la intubación con equipo de protección personal y la frecuencia de incumplimiento de un paso de seguridad fue estadísticamente significativa, aumentando el riesgo de infección cruzada. La opinión de los médicos senior difería de los más jóvenes en el videolaringoscopio utilizado, número de expertos involucrados en la intubación traqueal y la razón que provocó más estrés durante el manejo de la vía aérea.

Conclusiones

La mayoría de los médicos prefirieron usar un videolaringoscopio con monitor remoto y hoja Macintosh desechable, usando la guía Frova.

A survey of self-reported use of cricoid pressure amongst Australian and New Zealand anaesthetists: Attitudes and practice

We conducted a survey of Australian and New Zealand anaesthetists designed to quantify self-reported use of cricoid pressure (CP) in patients presumed to be at risk of gastric regurgitation, and to ascertain the underlying justifications used to support individual practice. We aimed to identify the perceived benefits and harms associated with the use of CP and to explore the potential impact of medicolegal concerns on clinical decision-making. We also sought to ascertain the views of Australian and New Zealand anaesthetists on whether recommendations relating to CP should be included in airway management guidelines. We designed an electronic survey comprised of 15 questions that was emailed to 981 randomly selected Fellows of the Australian and New Zealand College of Anaesthetists (ANZCA) by the ANZCA Clinical Trials Network on behalf of the investigators. We received responses from 348 invitees (response rate 35.5%). Of the 348 respondents, 267 (76.9%) indicated that they would routinely use CP for patients determined to be at increased risk of gastric regurgitation. When asked whether participants believed the use of CP reduces the risk of gastric regurgitation, 39.8% indicated yes, 23.8% believed no and 36.3% were unsure. Of the respondents who indicated that they routinely performed CP, 159/267 (60%) indicated that concerns over the potential medicolegal consequences of omitting CP in a patient who subsequently aspirates was one of the main reasons for using CP. The majority (224/337; 66%) of respondents believed that recommendations about the use of CP in airway management guidelines should include individual practitioner judgement, while only 55/337 (16%) respondents believed that routine CP should be advocated in contemporary emergency airway management guidelines.

The Knowledge of Health Professionals About the Application of Cricoid Pressure in a Low-Income Country: A Single-Center Survey Study

BACKGROUND

The application of cricoid pressure requires good knowledge and practice of health professionals who are working in operation theatres to prevent pulmonary aspiration. This study aims to assess the application of cricoid pressure knowledge and practice in health professionals who are working in the operation theatres.

METHODS

This survey-based study was conducted in health care professionals who are working in the operation theatre of Debre Tabor Comprehensive Specialized Hospital from November 1 to December 1, 2020. A structured checklist was used to collect data regarding the knowledge and practice of the application of cricoid pressure.

RESULTS

A total of 43 health professionals who are working in the operation theaters were involved in this study with a response rate of 81%. The correct anatomic position of cricoid cartilage was not identified in 67% of nurses. We found that 78% of anesthetists did not use the nasogastric tube for decompression, and 83% of them complain of difficult intubation during the application of cricoid pressure.

CONCLUSION

Health care professionals who are working in operation theatres had poor knowledge and practice in the application of cricoid pressure.

The Clinical Use of Cricoid Pressure: First, Do No Harm

Application of cricoid pressure (CP) during rapid sequence induction and intubation sequence has been a "standard" of care for many decades, despite limited scientific proof of its efficacy in preventing pulmonary aspiration of gastric contents. While some of the current rapid sequence induction and intubation guidelines recommend its use, other international guidelines do not, and many clinicians argue that there is insufficient evidence to either continue or abandon its use. Recently published articles and accompanying editorials have reignited the debate on the efficacy and safety of CP application and have generated multiple responses that pointed out the various (and significant) limitations of the available evidence. Thus, a critical discussion of available data must be undertaken before making a final clinical decision on such an important patient safety issue. In this review, the authors will take an objective look at the available scientific evidence about the effectiveness and safety of CP in patients at risk of pulmonary aspiration of gastric contents. We suggest that current data are inadequate to impose clinical guidelines on the use of CP because we acknowledge that currently there is not, and there may never be, a method to prevent aspiration in all patients. In addition, we reiterate that a universally accepted medical-legal standard for approaching the high-risk aspiration patient does not exist, discuss the differences in practice between the US and international practitioners regarding use of CP, and propose 5 recommendations on how future studies might be designed to obtain optimal scientific evidence about the effectiveness and safety of CP in patients at risk for pulmonary aspiration.

[New aspects of rapid sequence induction including treatment of pulmonary aspiration]

Pulmonary aspiration of solid components leads to displacement of the tracheobronchial tree, the aspiration of acidic gastric juices to chemical pneumonitis (Mendelson's syndrome) and the aspiration of oropharyngeal secretions or gastrointestinal pathogens to aspiration pneumonia. Principally, pulmonary aspiration can occur at any stage of anesthesia. In the clinical routine the aim must therefore be to identify those patients who have an increased risk of aspiration. When this is successful, measures can be taken to reduce the risk; these can be regional anaesthesia or the performance of general anaesthesia as rapid sequence induction (RSI). If severe pulmonary aspiration occurs despite all preventive measures, mostly during induction of anaesthesia, extensive experience and rapid action are necessary. This can only be achieved if the induction to RSI is performed by three persons with supervision of the trainee anaesthetist by a consultant anaesthetist.

Ultrasound guided paralaryngeal pressure versus cricoid pressure on the occlusion of esophagus: a crossover study

The primary objective of this study is to compare the effectiveness of cricoid pressure (CP) and paralaryngeal pressure (PLP) on occlusion of eccentric esophagus in patients under general anesthesia (GA). Secondary objectives include the prevalence of patients with central or eccentric esophagus both before and after GA, and the success rate of CP in occluding centrally located esophagus in patients post GA. Fifty-one ASA physical status I and II patients, undergoing GA for elective surgery were enrolled in this study. Ultrasonography imaging were performed to determine the position of the esophagus relative to the trachea: (i) before induction of GA, (ii) after GA before external CP maneuver, (iii) after GA with CP, and (iv) after GA with PLP. CP was applied to all patients whilst PLP via fingertip technique was only applied to patients with an eccentric esophagus. Among a total of 51 patients, 28 of them (55%) had eccentric esophagus pre GA, while this number increase to 33 (65%) after induction of GA. CP success rate was 100% in 18 patients with central esophagus post GA versus 27% in 33 patients with eccentric esophagus post GA (P<0.00001). Overall success rate for CP was 53%. In 33 patients with eccentric esophagus anatomy post GA, PLP success rate was 30% compared with 27% with CP (P=1.000). Ultrasound guided PLP fingertips technique was not effective in patients with an eccentrically located esophagus post GA. Ultrasound guided CP achieved 100% success rate in patients with a centrally located esophagus post GA.

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.

Nulla Per Os (NPO) guidelines: time to revisit?

PURPOSE OF REVIEW

Preoperative fasting guidelines are generalized to elective procedures and usually do not distinguish between the ambulatory and inpatient setting. Prevalence of aspiration is low while prolonged preoperative fasting is common clinical reality. Recently, changes in preoperative fasting guidelines have been widely discussed.

RECENT FINDINGS

Rates of prolonged clear fluid fasting (>4 h) prior to surgery are reported in up to 80% of patients with mean fasting duration of up to 16 h and beyond. Prolonged fasting may result in adverse effects such as intraoperative hemodynamic instability, postoperative delirium, patient discomfort, and extended hospital length of stay. Liberal approaches allowing clear fluids up to 1 h prior to anesthesia or until premedication/call to the operating room have shown no increase in adverse events among children. Various anesthesia societies now encourage clear fluid intake up to 1 h prior to pediatric elective anesthesia. Similar reports in the adult cohort are scarce.

SUMMARY

Allowing sips of water until call to the operating room may help reducing prolonged preoperative fasting and improving patient comfort while keeping a flexibility in operating room schedule. The feasibility and safety of a liberal clear fluid fasting regimen among adults undergoing elective anesthesia needs to be evaluated in future studies.

The effect of cricoid pressure on tracheal intubation in adult patients: a systematic review and meta-analysis

PURPOSE

This meta-analysis aimed to assess the impact of cricoid pressure (CP) application on intubation outcomes.

SOURCE

Electronic databases (i.e., MEDLINE, PubMed, Embase, and Cochrane review) were searched from inception to 2 June 2020 for randomized-controlled trials that assessed the intubation outcomes in adult patients using laryngoscopic approaches with and without the application of CP (i.e., CP vs non-CP group). The primary outcome was the successful first-attempt intubation rate (SFAIR), and the secondary outcomes were intubation time, incidences of poor laryngoscopic views (i.e., Cormack and Lehane grade 3-4), airway complications, and pulmonary aspiration.

PRINCIPAL FINDINGS

A total of five trials (published from 2005 to 2018) were included, and all tracheal intubations were performed by anesthesiologists or nurse anesthetists with a video (n = 3) or Macintosh laryngoscope (n = 2) in the operating room. We found no significant difference in SFAIR (risk ratio [RR], 0.98; P = 0.37), incidence of poor laryngoscopic views (RR, 1.49; P = 0.21), and risk of sore throat (RR, 1.17; P = 0.73) between the two groups. Nevertheless, the intubation time on the first successful attempt was slightly longer (weighted mean difference = 4.40 sec, P = 0.002) and risk of hoarseness was higher (RR, 1.70; P = 0.03) in the CP group compared with in the non-CP group. The secondary outcome "pulmonary aspiration" was not analyzed because only one trial was available.

CONCLUSION

The application of CP did not have a negative impact on the SFAIR or laryngoscopic view. Nevertheless, this maneuver may slightly prolong intubation time and increase the risk of postoperative hoarseness.