On 15 October 2015, the Resuscitation Council (UK) published the 5-yearly update on resuscitation guidelines. Not only does this include updates to basic life support (BLS), advanced life support (ALS), and neonatal and paediatric resuscitation, but also includes a detailed and expanded section covering pre-hospital resuscitation, aimed at all those involved in pre-hospital care, but particularly ambulance paramedics.
These guidelines are the culmination of a 5-year international process led by the International Liaison Committee on Resuscitation (ILCOR), involving the European Resuscitation Council (ERC) (of which the Resuscitation Council (UK) is a member), the American Heart Association (AHA), the Heart and Stroke Foundation of Canada (HSFC), the Australian and New Zealand Committee on Resuscitation (ANZCOR), the Resuscitation Council of Southern Africa (RCSA), the InterAmerican Heart Foundation (IAHF) and the Resuscitation Council of Asia (RCA). The process involves more than 500 experts in resuscitation who review all the published literature, collate and discuss the science and formulate a summary of the evidence. From this, each resuscitation council applies the evidence to its current guidelines and revises and updates them accordingly. The guidelines in 2010 have formed the framework on which the current 2015 revisions have been made, resulting in this year's resuscitation update.
The pre-hospital guidelines should be read in conjunction with the Resuscitation Council (UK) 2015 Resuscitation Guidelines, the Association of Ambulance Chief Executives and Joint Royal Colleges Ambulance Liaison Committee's UK Ambulance Services Clinical Practice Guidelines and local ambulance service protocols. These guidelines detail the application of the BLS and ALS guidelines to pre-hospital care and aim to improve the delivery of resuscitation in the challenging pre-hospital environment. They will also be used to inform and revise the current UK Ambulance Services Clinical Practice Guidelines, which will be updated shortly.
The pre-hospital guidelines cover clinical management both during the resuscitation attempt and also during post-resuscitation care, which is often a period when the patient is particularly unstable. In most cases of primary cardiac arrest, there is little to be gained by transporting a patient with ongoing resuscitation to hospital and it is generally recommended that resuscitation attempts should be terminated on scene if they have been unsuccessful. The main exception to this rule is those with penetrating trauma where immediate surgical intervention may be life saving if it cannot be performed on scene. When to not start resuscitation and when to stop resuscitation are also discussed, as there is now a much clearer approach to the appropriateness of pre-hospital resuscitation, taking into account the patient's wishes and the futility of prolonged resuscitation.
The most important factor in achieving successful resuscitation is the delivery of high-quality basic life support through an effective team approach. The guidelines emphasise the need for teamwork, situational awareness, leadership and decision making, delivered through effective command and control of a cardiac arrest in order to optimise all aspects of resuscitation.
Good quality chest compressions can be delivered both manually and by the use of mechanical chest compression devices. In 2006, the Joint Royal Colleges Ambulance Liaison Committee highlighted the absence of strong evidence supporting the use of mechanical CPR devices and recommended against their purchase for routine use pending results from large clinical trials. Since then, three large randomised controlled trials have evaluated the effectiveness of the LUCAS and Autopulse devices. As a result of the data analysed from these studies, the 2015 pre-hospital guidelines now suggest against the routine use of automated mechanical chest compression devices to replace manual chest compressions. They do suggest, however, that automated mechanical chest compression devices are a reasonable alternative to high-quality manual chest compressions in situations where sustained high-quality manual chest compressions are impractical or compromise provider safety, such as during patient transport to hospital in a moving ambulance or where good quality chest compressions cannot be maintained during extrication.
Airway management is a particularly contentious issue and most ambulance Trusts have sensibly moved towards a stepwise airway approach, incorporating supraglottic airways. Although there is no evidence for what constitutes an optimal airway, a significant number of patients in cardiac arrest still undergo tracheal intubation.
Pre-hospital complications from tracheal intubation are significant, and these guidelines aim to improve the safety and effectiveness of airway management by emphasising a stepwise approach, limiting the undertaking of tracheal intubation to those who are appropriately trained and competent in the procedure and ensuring the use of waveform capnography to confirm correct tube placement in patients where tracheal intubation is performed.
Ventilation is specifically mentioned in these guidelines because when performed too vigorously, it may reduce venous return and contribute to haemodynamic instability. This is particularly in patients with hypovolaemia or shock, even to the extent of inducing re-arrest. Hyperventilation can result from excessive tidal volumes, respiratory rate, or both, so it is important to remember that gentle ventilation should be delivered both during resuscitation and also following return of spontaneous circulation (ROSC). The optimal concentration of oxygen delivered during resuscitation is not known, but there is some evidence that excessive oxygenation may result in worse outcome, possible through generation of free radicals and other inflammatory pathways. During cardiac arrest, it is recommended to use 100% oxygen, but once ROSC is achieved, aim for SpO2 94–98%.
Over the past 5 years, there have been no significant studies about defibrillation energy levels, so these remain unchanged from the 2010 guidelines. A period of chest compression prior to defibrillation has not been shown to improve outcome, and attaching the defibrillation electrodes and delivering the first shock as soon as possible remains a priority. When attending as a solo responder, immediate assessment of the rhythm and defibrillation when indicated, should take precedence over airway or breathing interventions. Immediate defibrillation should always be performed in patients where a shockable rhythm is identified on the ECG, irrespective of the amplitude.
Vascular access has always been particularly challenging during cardiac arrest and the use of intraosseous access is now a well-established alternative to intravenous cannulation. It is recommended that paramedics have no more than two attempts at gaining IV access before considering intraosseous access.
Although there are no changes to the use of adrenaline during cardiac arrest, there is considerable debate as to its effectiveness in cardiac arrest. Current evidence suggests that although adrenaline may increase ROSC rates, it may not improve neurologically intact survival to hospital discharge and may even worsen the overall outcome. A large UK ambulance study (PARAMEDIC2) is now underway to ascertain whether adrenaline is as effective as once thought. In patients achieving ROSC, small increments of IV adrenaline (0.1 mg) are now recommended in those who are becoming significantly hypotensive, despite IV fluids, although the benefit of this therapy is as yet unproven.
The pre-hospital guidelines also provide advice about the management of patients suffering cardiac arrest as a result of drowning, drug overdose, pregnancy, anaphylaxis, asthma and trauma. The drowning guidelines deserve special mention, as they have been developed in conjunction with the UK Fire and Rescue Service National Operational Guidance Programme to ensure that all emergency and rescue services are finally working to the same guidance. Guidelines on the management of trauma are extensive and emphasise the need to address reversible causes, and control active haemorrhage.
Finally, the guidelines discuss the optimal patient destination and also recommend how to give an effective pre-alert and handover to the hospital team.
These guidelines should be read in conjunction with the updated BLS and ALS guidelines, together with the paediatric and neonatal updates, as they focus on the pre-hospital delivery of resuscitation rather than the revisions to the actual resuscitation guidelines themselves. They aim to aid the practical delivery of resuscitation and the authors would welcome feedback ahead of the next scheduled revision in 2020.