The adult ergonomic face mask concept: historical and theoretical perspectives

Comparison of Effectiveness of CE Technique and Jaw Thrust Technique for Mask Ventilation on Apneic Anesthetized Adults: A Randomized Controlled Trial

Background

The two most common techniques for mask ventilation are CE and jaw thrust (JT) technique. However, few studies have validated their efficiency in terms of tidal volume (TV).

Aims

This study aimed to compare the effectiveness of the CE technique and JT technique during pressure-controlled ventilation (PCV) by the mean of returned TV on apneic anesthetized adults.

Design

This was a prospective, randomized cross over study.

Settings

This study was conducted in a tertiary care hospital.

Methods

Ethical Committee approval from our institution was taken (ss-1/EC 049/2017) and was registered in Clinical Trials Registry of India (CTRI/2018/04/012958). Sixty-five American Society of Anesthesiologists Physical Status classes I and II adult patients were enrolled in the study. After induction and muscle relaxation, mask ventilation was performed with CE and JT technique on PCV mode (Pinsp 15 cm H2O, respiratory rate 15) for 1 min each. The mean of returned TV of last 12 breaths, gastric insufflation, audible mask leak, and operator comfort in each technique were compared.

Statistical Analysis

Statistical software namely IBM SPSS 22.0 and R environment version 3.2.2 (IBM Corp. SPSS Statistics for Windows, Version 22.0. Armonk, NY, USA) were used for data analysis. Microsoft Excel was used to generate graphs and tables. Data were expressed as mean ± standard deviation for continuous variables and number (%) for categorical variables. Student's t-test (two tailed, independent) was used to find the significance of the study parameters on a continuous scale. Chi-square/Fisher's exact test was used to find the significance of the study parameters on a categorical scale between two or more groups.

Results

There was a significant increase in mean TV generated by JT technique over CE technique (591.46 ± 140.27 mL vs. 544.59 ± 159.08 mL; P < 0.001). Gastric insufflation (12.9% vs. 14.5%) and mask leak (11.3% vs. 38.7%) were more in CE technique. Operator comfort (79% vs. 19.4%) was more in JT technique.

Conclusion

A two-handed JT technique is more effective than a one-handed CE technique for mask ventilation in apneic anesthetized adults.

[History of surgical and non-surgical tracheal intubation]

Anesthesiologist daily encounters the need for maintaining an airway patency. This manuscript is devoted to the development of this technique from ancient times to the present. Three areas including tracheostomy, endoscopy and tracheal intubation are comprehensively described.

An Anesthesiologist's Perspective on the History of Basic Airway Management: The "Modern" Era, 1960 to Present

This fourth and last installment of my history of basic airway management discusses the current (i.e., "modern") era of anesthesia and resuscitation, from 1960 to the present. These years were notable for the implementation of intermittent positive pressure ventilation inside and outside the operating room. Basic airway management in cardiopulmonary resuscitation (i.e., expired air ventilation) was de-emphasized, as the "A-B-C" (airway-breathing-circulation) protocol was replaced with the "C-A-B" (circulation-airway-breathing) intervention sequence. Basic airway management in the operating room (i.e., face-mask ventilation) lost its predominant position to advanced airway management, as balanced anesthesia replaced inhalation anesthesia. The one-hand, generic face-mask ventilation technique was inherited from the progressive era. In the new context of providing intermittent positive pressure ventilation, the generic technique generated an underpowered grip with a less effective seal and an unspecified airway maneuver. The significant advancement that had been made in understanding the pathophysiology of upper airway obstruction was thus poorly translated into practice. In contrast to consistent progress in advanced airway management, progress in basic airway techniques and devices stagnated.

An Anesthesiologist's Perspective on the History of Basic Airway Management: The "Progressive" Era, 1904 to 1960

This third installment of the history of basic airway management discusses the transitional-"progressive"-years of anesthesia from 1904 to 1960. During these 56 yr, airway management was provided primarily by basic techniques with or without the use of a face mask. Airway maneuvers were inherited from the artisanal era: head extension and mandibular advancement. The most common maneuver was head extension, also used in bronchoscopy and laryngoscopy. Basic airway management success was essential for traditional inhalation anesthesia (ether, chloroform) and for the use of the new anesthetic agents (cyclopropane, halothane) and intravenous drugs (thiopental, curare, succinylcholine). By the end of the era, the superiority of intermittent positive pressure ventilation to spontaneous ventilation in anesthesia and negative pressure ventilation in resuscitation had been demonstrated and accepted, and the implementation of endotracheal intubation as a routine technique was underway.

Comparison of modified chin lift technique with EC technique for mask ventilation in adult apneic patients

Background:

Mask ventilation (MV) is an essential basic life support skill. We used chin lift maneuver for MV and named as modified chin lift technique (MCL). EC technique is most common technique used for MV.

Aims:

The aim of this study is to compare the efficacy of both techniques for MV in term of expired tidal volume (TV). Secondarily, we also assessed the effect of experience on the performance of these both techniques.

Settings and Design:

The study area was operation theater of our hospital. This was a prospective, randomized, crossover study.

Methods:

A total 108 adults undergoing elective surgery under general anesthesia were recruited. In all patients, operators (novice/anesthesiologist) randomly performed both techniques either to start with EC or MCL technique. Expired TV was measured for one minute for each technique.

Statistical Analysis:

Paired t-test was used to compare TV.

Results and Conclusion:

The mean TV was significantly higher in MCL group than EC group (528.08 [104.96] ml vs. 483.39 [103] ml; P < 0.001). The novice (521.89 [117.9] ml vs. 478.70 [130.29] ml; P < 0.001) as well as anesthesiologists (534.27 [110.85] ml vs. 488.08 [111.6] ml; P < 0.001) was able to generate significantly more TV with MCL technique than EC technique. The TV did not differ significantly between novice and anesthesiologist for EC technique (P = 0.474) or MCL technique (P = 0.187). Novices as well as anesthesiologist felt MCL technique more satisfactory (70%).

Clinical Trial Registration:

CTRI/2016/04/006874.

Oral mask ventilation is more effective than face mask ventilation after nasal surgery

OBJECTIVE

To evaluate and compare the face mask (FM) and oral mask (OM) ventilation techniques during anesthesia emergence regarding tidal volume, leak volume, and difficult mask ventilation (DMV) incidence.

DESIGN

Prospective, randomized, crossover study.

SETTING

Operating room, training and research hospital.

SUBJECTS

American Society of Anesthesiologists physical status I and II adult patients scheduled for nasal surgery.

INTERVENTIONS

Patients in group FM-OM received FM ventilation first, followed by OM ventilation, and patients in group OM-FM received OM ventilation first, followed by FM ventilation, with spontaneous ventilation after deep extubation. The FM ventilation was applied with the 1-handed EC-clamp technique. The OM was placed only over the mouth, and the 1-handed EC-clamp technique was used again. A child's size FM was used for the OM ventilation technique, the mask was rotated, and the inferior part of the mask was placed toward the nose.

MEASUREMENTS

The leak volume (MVleak), mean airway pressure (Pmean), and expired tidal volume (TVe) were assessed with each mask technique for 3 consecutive breaths. A mask ventilation grade ≥3 was considered DMV.

MAIN RESULTS

DMV occurred more frequently during FM ventilation (75% with FM vs 8% with OM). In the FM-first sequence, the mean TVe was 249±61mL with the FM and 455±35mL with the OM (P=.0001), whereas in the OM-first sequence, it was 276±81mL with the FM and 409±37mL with the OM (P=.0001). Regardless of the order used, the OM technique significantly decreased the MVleak and increased the TVe when compared to the FM technique.

CONCLUSION

During anesthesia emergence after nasal surgery the OM may offer an effective ventilation method as it decreases the incidence of DMV and the gas leak around the mask and provides higher tidal volume delivery compared with FM ventilation.

Management of the airway in multitrauma

PURPOSE OF REVIEW

The primary purpose of this article is to highlight the latest airway research in multitrauma.

RECENT FINDINGS

Management of the airway in multitrauma patients is a critical resuscitation task. Prehospital airway management is difficult with a high risk of failure, complications, or both. In-hospital performed conventional oral intubation with manual in-line stabilization, cricoid pressure, and a backup plan for a surgical airway is still the most efficient and effective approach for early airway control in multitrauma patients. Selective utilization of airway maintenance, instead of ultimate airway control in the field, has been suggested as a primary prehospital strategy. Properties of videolaryngoscopes complement standard laryngoscopes. When compared with a Macintosh laryngoscope, the Airtraq and Airwayscope diminish cervical spine motion during elective orotracheal intubation. Penetrating neck injuries are the most frequent indication for awake intubation, whereas patients with maxillofacial injuries have the highest rate of initial surgical airway.

SUMMARY

Risks and benefits of ultimate prehospital airway control is a controversial topic. Utilization of videolaryngoscopes in multitrauma remains open for research. Standardization of training requirements, equipment, and development of prehospital and in-hospital airway algorithms are needed to improve outcomes. Rational utilization of available airway devices, development of new devices, or both may help to promote this goal.