Head Positions to Open the Upper Airway
Condition: Apnea; Cardiopulmonary Resuscitation
Study type: Interventional

Summary: 
      Ventilation during basic life support improves survival in cardiac arrest patients
      significantly. Unfortunately, this is in contrast to the willingness of potential rescuers to
      perform mouth-to-mouth ventilation. For example, although healthcare professionals would
      perform mouth-to-mouth ventilation on a 4-year old drowned child in >90% of cases, this
      likelihood would decrease to ~10% in the case of a young male unconscious patient in a San
      Francisco public bus. Possibly, lay rescuers would perform assisted ventilation more often if
      a simple ventilation device were available. However, both the willingness to perform assisted
      ventilation plus the ability to open and to maintain the airway patent are necessary to
      ensure efficient ventilation in an unconscious patient with an unprotected upper airway.

      Since retention of skills after basic life support classes are notoriously low, a
      resuscitation tool should incorporate self-explanatory features to improve applicability, and
      to provide built-in safety. Thus, an option could be to ensure an open airway by the use of a
      built-in indicator within a ventilating device to confirm correct head extension. One
      possible approach may be to determine head position angles that make an open airway likely,
      and integrate these angles into a scale on a ventilating device; however, safe head extension
      needs to be determined first to prevent harm.

      The purpose of this study is to determine head position angles and ventilation parameters
      reflecting neutral position, maximal extension and a position deemed optimal by an
      anaesthesiologist in patients undergoing anaesthesia induction for elective surgery in a
      first step to design a ventilating device to optimise ventilation of an unprotected upper
      airway. The investigators will ventilate 30 patients with a pillow under the head simulating
      ventilation in the operating theater, and 30 patients without a pillow under the head
      simulating ventilation during cardiopulmonary resuscitation.

      Dentures will not be removed during assessment. After anaesthesia induction the head will be
      consecutively flexed in the three positions and measurements performed. Afterwards, general
      anaesthesia and surgery will ensue. The health risk for this extra minutes of mask
      ventilation is minimal.

      The null hypothesis is that there will be no differences in head position angles and
      ventilation parameters.
    


Intervention name(s): Extension; Neutral head position; Anaesthesiologist's position
Intervention type(s): Procedure; Procedure; Procedure
Intervention description(s): After anaesthesia induction the head is placed in extension; After anaesthesia induction the head is placed in neutral position; after anaesthesia induction the head is placed in a position deemed optimal by the anaesthesiologist
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary purpose: Treatment
Keywords: Airway; Anaesthesia; Resuscitation; Ventilation