Elsevier

Resuscitation

Volume 41, Issue 1, June 1999, Pages 63-69
Resuscitation

Airway management during cardiopulmonary resuscitation—a comparative study of bag–valve–mask, laryngeal mask airway and combitube in a bench model

https://doi.org/10.1016/S0300-9572(99)00036-2Get rights and content

Abstract

Gastric inflation and subsequent regurgitation are a potential risk of ventilation during cardiopulmonary resuscitation (CPR). In respect of recent investigations, principal respiratory components such as respiratory system compliance, resistance and lower esophageal sphincter pressure were adapted according to CPR situations. The purpose of our study was to assess lung ventilation and gastric inflation when performing ventilation with bag–valve–mask, laryngeal mask airway, and combitube in a bench model simulating an unintubated cardiac arrest patient. Twenty-one student nurses, without any experience in basic life support measures, ventilated the bench model with all three devices. Mean (±S.D.) gastric inflation with the laryngeal mask airway (seven cases) was significantly lower than with the bag–valve–mask (0.6±0.81 vs 3.0±2.1 l min−1, P<0.01). There was no gastric inflation when ventilation was performed with the combitube. Only seven of 21 volunteers exceeded 1-min lung volumes of >5 l when using the bag–valve–mask, whereas mean (±S.D.) 1-min lung volumes with both laryngeal mask airway and combitube were significantly higher (laryngeal mask airway 15.0±6.6 l, combitube 16.6±6.8 l vs bag–valve–mask 4.8±2.7 l, P<0.01). The time for insertion was significantly faster with both bag–valve–mask and laryngeal mask airway compared with the combitube (median: bag–valve–mask 22 s, laryngeal mask airway 37 s vs combitube 70 s, P<0.01). This may tip the scales towards using the laryngeal mask airway during basic life support airway management. In conclusion, our data suggests that both laryngeal mask airway and combitube may be appropriate alternatives for airway management in the first few minutes of CPR.

Introduction

Tracheal intubation is the gold-standard of airway management during cardiopulmonary resuscitation (CPR). However, intubation skills require an extensive period of training and continuous practice. Accordingly, it has been recommended to perform bag–valve–mask ventilation in an unintubated cardiac arrest patient until rescuers arrive who are capable of performing advanced cardiac life support. Although other airway devices such as the laryngeal mask airway [1], [2] and the combitube [3] have been suggested as alternatives for the basic life support phase management of the airway, it is unclear whether healthcare professionals who have no formal training in using these devices can use them adequately.

Performing bag–valve–mask ventilation may be difficult, especially for healthcare workers with infrequent experience in difficult conditions such as cardiac arrest. For example, recent observations of the lower esophageal sphincter pressure during cardiac arrest indicate that respiratory mechanics may be significantly altered rendering gastric inflation during bag–valve–mask ventilation very likely. As such, both pulmonary hypoventilation and gastric inflation induced during the basic life support phase may adversely affect patient outcome. Also, compliance of the respiratory system during CPR may change significantly [4], [5]. Using an alternative airway device such as the laryngeal mask airway or the combitube may improve ventilation, and decrease ventilation-associated complications such as gastric inflation.

However, it is unknown whether nursing staff who have been minimally trained in basic life support airway management may be able to adequately employ these alternative airway devices.

Accordingly, the purpose of the study was to assess lung ventilation and gastric inflation when performing ventilation with bag–valve–mask, laryngeal mask airway, and combitube in a bench model simulating an unintubated cardiac arrest patient.

Section snippets

Experimental model

Pilot experiments revealed that conventional CPR mannequin heads may not serve as an adequate bench model for evaluation of the combitube and laryngeal mask airway. For example, it is almost impossible to achieve a sufficient seal of the oropharynx with the oropharyngeal cuff of the combitube, or to accurately locate the laryngeal mask airway. We used a recently developed mannequin head (VBM Medizintechnik, Sulz, Germany) with a smaller diameter of the oropharynx, which enables realistic

Results

Twenty-one training nurses (17 female, 4 male; age 21–43) performed ventilation on our bench model with bag–valve–mask, laryngeal mask airway, and combitube, respectively. Four participants exceeded the time limit for the first adequate ventilation (180 s, lung volume >200 ml) in the bag–valve–mask group, two in the combitube group, and no one in the laryngeal mask airway group. Within 3 min, the success rate for the first adequate ventilation was 100% for the laryngeal mask airway, 90% for the

Discussion

Tracheal intubation is the gold standard to secure the airway during CPR. However, performing tracheal intubation requires excellent skills and experience, and therefore, is usually performed by professional rescuers. Hence, particularly during basic life support management of a cardiac arrest victim, the standard recommendation for ventilation has been to use the bag–valve–mask while waiting for a professional rescuer who is capable of advanced airway management such as tracheal intubation [6].

Acknowledgements

The authors would like to thank our nursing school and the student nurses for participating in our study. We also gratefully acknowledge the support of Thomas Meyer.

References (31)

  • J.P. Ornato et al.

    Measurement of ventilation during cardiopulmonary resuscitation

    Crit. Care Med.

    (1983)
  • Airway and Ventilation Management Working Group of the European Resuscitation Council. Guidelines for the basic...
  • R. Alexander et al.

    A comparison of the laryngeal mask airway and Guedel airway for manual ventilation following formal training

    Anaesthesia

    (1993)
  • V. Wenzel et al.

    The current status of ventilation strategies during cardiopulmonary resuscitation (CPR)

    Curr. Opin. Crit. Care

    (1997)
  • J.A. Johannigman et al.

    Techniques of emergency ventilation: a model to evaluate tidal volume, airway pressure and gastric inflation

    J. Trauma

    (1991)
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