Pre-hospital Anaesthesia: The Same but Different
Pre-hospital Anaesthesia: The Same but Different
One of the key questions in the provision of pre-hospital anaesthesia for trauma patients is whether there is genuine demand for the intervention. If airway management which stops short of pre-hospital anaesthesia is adequate for victims of major trauma, then the provision of pre-hospital anaesthesia may be unnecessary. Unfortunately, the published literature does not support this concept. The National Confidential Enquiry into patient outcome and death—Trauma Who Cares? Published in 2007 reported a significant number of patients who arrived in the emergency department after suffering traumatic injury with airway compromise after on-scene management by ambulance paramedics. In the USA, an examination of trauma patients arriving in hospital demonstrated that ~10% required intubation in the emergency department. Around half of the patients who required intubation had immediate indications such as airway obstruction, ventilatory failure, or cardiac arrest, which are highly unlikely to have developed on arrival in the emergency department. Similarly in a Norwegian EMS, Sollid and colleagues demonstrated that a substantial number of trauma patients were only intubated on arrival in the emergency department despite having clear indications for RSI before arrival in hospital. The exact demand for pre-hospital anaesthesia in trauma patients is difficult to quantify. Ideally, it would be useful to understand what proportion of major trauma patients meet the criteria for immediate intubation on scene and also to establish what proportion of these can be safely managed with more basic airway management. When poor performance is reported in systems where pre-hospital anaesthesia is not available, it is difficult to establish whether this is because the available, more basic interventions are inadequate or were not carried out properly.
The discussions about the potential advantages and drawbacks of pre-hospital anaesthesia (and other pre-hospital interventions) are often related to time. There is little doubt that pre-hospital interventions increase time on scene. This is often only by a small margin and increased scene time is not necessarily associated with increased mortality. What is clear is that, regardless of the interventions carried out, total pre-hospital times are quite consistent in different EMS systems and the 'scoop and run' concept rarely results in trauma patients arriving in the emergency department minutes after injury. In the small proportion of trauma patients who have airway compromise on scene, there may be a considerable interval before in hospital RSI is possible. In addition, the actual time of RSI might well be some time after arrival in the emergency department. In patients who require immediate intubation in the emergency department delay is unacceptable and is one of the quality indicators of trauma care measured in the UK Trauma Audit and Research Network. The patients outside hospital are the same patients earlier in the patient pathway and the concept of 'Critical care without walls' could be applied to the critically ill with airway compromise outside hospital in the same way as the critically unwell patient on the general hospital ward.
Less immediate indications are also used for pre-hospital anaesthesia—humanitarian in severe injury or perhaps severe agitation without airway compromise. In these situations, the risk–benefit ratio is different and, as survival or disability is unlikely to be prevented by immediate RSI, the provider must be confident that the intervention can be delivered with minimal risk. This is likely to require an experienced provider working with established clinical governance processes.
Is There Real Need for Pre-hospital Anaesthesia?
One of the key questions in the provision of pre-hospital anaesthesia for trauma patients is whether there is genuine demand for the intervention. If airway management which stops short of pre-hospital anaesthesia is adequate for victims of major trauma, then the provision of pre-hospital anaesthesia may be unnecessary. Unfortunately, the published literature does not support this concept. The National Confidential Enquiry into patient outcome and death—Trauma Who Cares? Published in 2007 reported a significant number of patients who arrived in the emergency department after suffering traumatic injury with airway compromise after on-scene management by ambulance paramedics. In the USA, an examination of trauma patients arriving in hospital demonstrated that ~10% required intubation in the emergency department. Around half of the patients who required intubation had immediate indications such as airway obstruction, ventilatory failure, or cardiac arrest, which are highly unlikely to have developed on arrival in the emergency department. Similarly in a Norwegian EMS, Sollid and colleagues demonstrated that a substantial number of trauma patients were only intubated on arrival in the emergency department despite having clear indications for RSI before arrival in hospital. The exact demand for pre-hospital anaesthesia in trauma patients is difficult to quantify. Ideally, it would be useful to understand what proportion of major trauma patients meet the criteria for immediate intubation on scene and also to establish what proportion of these can be safely managed with more basic airway management. When poor performance is reported in systems where pre-hospital anaesthesia is not available, it is difficult to establish whether this is because the available, more basic interventions are inadequate or were not carried out properly.
The discussions about the potential advantages and drawbacks of pre-hospital anaesthesia (and other pre-hospital interventions) are often related to time. There is little doubt that pre-hospital interventions increase time on scene. This is often only by a small margin and increased scene time is not necessarily associated with increased mortality. What is clear is that, regardless of the interventions carried out, total pre-hospital times are quite consistent in different EMS systems and the 'scoop and run' concept rarely results in trauma patients arriving in the emergency department minutes after injury. In the small proportion of trauma patients who have airway compromise on scene, there may be a considerable interval before in hospital RSI is possible. In addition, the actual time of RSI might well be some time after arrival in the emergency department. In patients who require immediate intubation in the emergency department delay is unacceptable and is one of the quality indicators of trauma care measured in the UK Trauma Audit and Research Network. The patients outside hospital are the same patients earlier in the patient pathway and the concept of 'Critical care without walls' could be applied to the critically ill with airway compromise outside hospital in the same way as the critically unwell patient on the general hospital ward.
Less immediate indications are also used for pre-hospital anaesthesia—humanitarian in severe injury or perhaps severe agitation without airway compromise. In these situations, the risk–benefit ratio is different and, as survival or disability is unlikely to be prevented by immediate RSI, the provider must be confident that the intervention can be delivered with minimal risk. This is likely to require an experienced provider working with established clinical governance processes.