The Unique Challenges of Pre-Hospital Airway Management
We start the activity “Airway Management in the Critically Ill” with this article by Tim Edwards, Consultant Paramedic at London Ambulance Service, discussing the challenges of pre-hospital airway management.
Pre-hospital airway management is associated with a unique set of challenges not routinely encountered in other clinical environments . Efforts to manage the airway may be hampered by:
- the location of the patient
- environmental factors
- the behaviour of bystanders or relatives
- the availability of sufficient numbers of skilled personnel
Techniques used in more controlled clinical environments may require adaptation or simply prove unsuitable in pre-hospital care.
The requirement for pre-hospital airway management may range from basic airway adjuncts such as oropharyngeal and nasopharyngeal airways through to supraglottic airway devices and tracheal intubation. Rarely cricothyroidotomy may be required.
Airway Management in UK Ambulance Services
The majority of pre-hospital airway management within the UK is performed by paramedics and emergency medical technician (EMT) staff .
They are registered healthcare professionals trained in basic airway management techniques with some able to insert supraglottic airway devices and perform tracheal intubation. In some settings advanced paramedics will use additional airway techniques such as videolaryngoscopy, cricothyroidotomy and sedation for airway tolerance following return of spontaneous circulation. Pre-hospital anaesthesia may be provided as part of physician-paramedic teams operating predominantly as part of air ambulance services .
Human factors play a major role in pre-hospital airway management and are frequently incorporated as part of airway management and resuscitation training for paramedics and other ambulance clinicians.
Strategies to reduce cognitive load and prevent task fixation in challenging environments are designed to reduce the potential for error and promote situation awareness, particularly where advanced airway management techniques are used. Simulation has a major role to play in preparing trainees for the pre-hospital environment.
Current Issues and Controversies in Pre-hospital Airway Management
Advanced airway management including tracheal intubation has been a core component of paramedic training for decades . However, recent research has questioned the value of this technique in pre-hospital care particularly in settings where procedural exposure is low . This is further compounded by reduced opportunities for supervised practice in tracheal intubation due to the emergence of supraglottic airway devices in hospital settings. This contrasts with procedural success rates in services where smaller groups of paramedics are selectively targeted to cases requiring advanced airway management .
The majority of advanced airway management undertaken by UK paramedics is in the context of cardiac arrest. Some observational studies have identified increased survival associated with tracheal intubation , whereas others report worsened outcomes .
The UK AIRWAYS 2 randomised trial comparing tracheal intubation versus supraglottic airway devices in out-of-hospital cardiac arrest found no difference in survival, but noted a trend towards worsened outcomes where tracheal intubation was performed in the presence of a shockable rhythm . In the setting of major trauma, outcomes are generally dismal for patients able to tolerate an advanced airway without sedation or paralysis .
PQRST - A Framework for Prehospital Airway Management
P – Patient, Position, Personnel
- Patient: an initial airway assessment should be undertaken to identify features predictive of a difficult airway.
- Position: this may restrict the range of airway management techniques that can be applied and may mean that temporising measures are needed until the patient can be repositioned or extricated to an area with more space.
- Personnel: their number and skill set may dictate how quickly the patient can be moved and the range of airway techniques available. Where there are limited personnel available or there is a lack of expertise with airway techniques, it may be better to postpone more technically demanding procedures such as tracheal intubation until sufficient help is available. Where tracheal intubation is attempted a skilled assistant should be available, placing the patient on an ambulance trolley bed helps optimise laryngoscopy.
Q – Quality cardiopulmonary resuscitation
The majority of pre-hospital advanced airway management is performed in the context of cardiac arrest, where the emphasis is on interventions known to improve survival such as good quality chest compressions and prompt defibrillation.
Airway operators must always ensure that escalating airway interventions do not adversely affect the quality of chest compression and resuscitation attempts .
R – Rhythm
If cardiopulmonary resuscitation is in progress, and there is a shockable rhythms it may be better to delay or omit advanced airway management in favour of high quality chest compressions and prompt defibrillation. Conversely patients in cardiac arrest following respiratory disease or asphyxia may benefit from early advanced airway management.
S – Select the intervention
The best way of managing the airway depends on the available personnel, the position of the patient and the clinical requirements.
T – Timing and Transfer
The timing of definitive airway management may depend on the need to initiate hospital transfer. More complex techniques may need to be postponed until there is adequate access to the patient. Some evidence suggests improved outcomes where tracheal intubation is delayed until return of spontaneous circulation. Early transfer to a receiving hospital may be more appropriate than securing the airway at the scene.
Pre-hospital airway management employs many of the techniques used in a hospital setting, but these may require adaptation. Availability of personnel, patient position and environmental concerns are frequently complicating factors.
Have you experienced airway management in the pre-hospital setting? What challenges did you encounter? How are Human Factors and Ergonomics addressed in the prehospital setting?
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© UCL, materials shared with permission from the London Ambulance Service