As previously reported on this blog page, the optimum method for management of the airway during cardiac arrest (CA) continues to be the subject of lively debate. The European Resuscitation Council (ERC) guidelines confirm that ‘There are no data supporting the routine use of any specific approach to airway management during cardiac arrest. The best technique is dependent on the precise circumstances of the cardiac arrest and the competence of the rescuer.’
With regard to the use of supraglottic airways (SADs) for CA, the call went out in an editorial entitled ‘Airway Management for out-of-hospital cardiac arrest – more data required’, published in 2009 in Resuscitation by Nolan and Lockey for high quality randomised controlled trials (RCTs) of the use of SADs for cardiopulmonary resuscitation (CPR). The REVIVE airways study process is an attempt to provide just such evidence by conducting a randomised comparison of the ventilation success of two 2nd generation supraglottic airways, i-gel® and the LMA Supreme®, in the initial airway management of OHCA compared to current practice, which is expected to be tracheal intubation. The REVIVE team published an initial report in the BMJ on the feasibility of such a study protocol earlier this year. A full trial is expected to follow.
In the meantime, healthcare professionals are still faced with the dilemma of which airway device to use for CPR, so any new data or evidence in this area, even if it is not high level, is likely to be of interest.
Duckett et al have just published the results of two retrospective clinical audits in the Emergency Medicine Journal, reviewing the use of basic and advanced airway management techniques within the UK North East Ambulance Service NHS Foundation Trust (NEAS) for cardiac arrests, entitled, ‘Introduction of the i-gel supraglottic airway device for prehospital airway management in a UK ambulance service.’
The audit confirmed that a range of basic and advanced airway management techniques are being successfully used to manage the airways of CA patients in NEAS and that i-gel is emerging as a popular choice for maintaining and securing the airway during pre-hospital CPR.
The success rates for i-gel insertion at 94% and 92% were higher than for the endotracheal tube (ETT) at 90% and 86%. In determining these results, the Quality Improvement Officer audited whether the technique used had been documented by the crew as ‘successful’ or ‘unsuccessful’, but no further details are provided in this report as to how success or failure was determined. Any additional relevant documentation which may indicate problems such as regurgitation, aspiration or trauma provided by the paramedic and/or the receiving A&E department were also considered. The abstract reports that ‘The re-audit indicated an upward trend in the popularity of i-gel; insertion is faster with a higher success rate, which allows the crew to progress with the other resuscitation measures more promptly.’
In light of this new data, it is interesting to note that an addition to the i-gel product range, specially designed for use during resuscitation, is also now available. The i-gel O2 Resus Pack (figure 1) contains a modified i-gel with a supplementary oxygen port.
It also includes a sachet of lubricant for quick and easy lubrication of the i-gel O2 prior to insertion, an airway support strap to secure the i-gel O2 in position and a suction tube for insertion through the gastric channel to empty the stomach contents (figure 2)
The i-gel O2 has been designed to facilitate ventilation as part of standard resuscitation protocols (figure 3), such as those designated by the ERC.
However, the i-gel O2 incorporates a supplementary oxygen port, permitting use for the delivery of passive oxygenation (figure 4), or Passive Airway Management (PAM), as part of an appropriate CardioCerebral Resuscitation (CCR) protocol. The use of passive oxygenation is discussed in an earlier blog post, Should we be passive about oxygenation?
Returning to the study from NEAS – it may not be a randomised controlled trial as called for by Nolan and Lockey, but it still represents a welcome and useful addition to the data regarding use of airway devices in the prehospital setting.