Time-critical transfers by referring clinicians
Background
The development of stand-alone retrieval services across the globe has enhanced the quality of care on transport for critically ill and injured patients. These retrieval teams cover neonatal, paediatric, obstetric and adult patients and may utilize tertiary level intensive therapies such as inhaled nitric oxide, IABPs, active cooling and extracorporeal life support. However, the capacity for retrieval team support may be overwhelmed due to multiple demands for transport or transport logistics, for example adverse weather. In specific clinical situations there may be an urgency to transport the patient to the site of definitive care where a delay waiting on a retrieval team necessitates transport by the referring hospital team. This discussion outlines the key decision making issues when considering referring vs retrieval team transport.
Learning outcomes
1 Identify advantages and disadvantages of retrieval team transport
2 Outline the principles of equipment for referring team transport
3 Outline the process for referring team transport.
CPD matrix matches
2A11; 2D07; 2F01
Case history: identifying the advantages and disadvantages of retrieval team transport
An 11-year-old boy has fallen off his bicycle and crashed into a tree at high speed, striking his head on the main trunk. He was reported to be GCS 10 at the scene but has become increasingly drowsy en route into hospital, and he was GCS 6 on arrival in your ED, 20 min after the incident. He has been anaesthetized and ventilated, and a CT of the head demonstrates a large bifrontal extradural haematomas (see Figure 14.5). You work in a large district general hospital which has general and trauma surgeons, paediatricians, and anaesthetists, but no neurosurgery or paediatric intensive care facilities. Your nearest neurosurgical unit is 100 miles away.
Fig. 14.5 Large bifrontal extradural haematomas.
What are the options for the emergency management of this child’s life-threatening injury?
This child needs an emergency evacuation of his intracranial haematoma. There are essentially three options to facilitate this procedure: perform the surgery in the referring hospital, referring team transport, or retrieval team transport to the neurosurgical centre.
◆ Local surgery: a discussion on the surgical options is outwith the scope of this anaesthetic text; however, cases have been reported where lifesaving haematoma decompression, by way of burr holes, has been performed by remote and rural practitioners, with limited experience, under the telephone guidance of neurosurgeons. There is no doubt that many of these procedures have been successful in the past, but great concern has been expressed regarding this practice from neurosurgeons. Whilst the emergency burr hole may relieve critical intracranial hypertension, the referring practitioner may have very limited ability or equipment to deal with persistent arterial or venous bleeding and may, in fact, release a relative tamponade that leads to major haemorrhage. The risk of this is such that the standard neurosurgical approach to these cases is typically by craniotomy, so that bleeding vessels may be identified and ligated in the primary procedure, a procedure such as this being beyond the scope of a referring unit
◆ Referring team transport: transfer of this ventilated patient by one of the local anaesthetists may appear, on the face of it, to be the most rapid method of achieving definitive care, but there are many facets to review. The Royal College of Anaesthetists mandates that any unit which receives critically ill patients must have the capacity to transfer them to definitive care, which includes the consideration of staff, equipment, protocols, and a governance system relating to transport episodes. Any ventilated patient must be accompanied by an anaesthetist on transport. Guidelines, produced by the AAGBI, state that any anaesthetist transferring a patient, such as this child with a traumatic brain injury, must be trained in paediatric anaesthesia, neurocritical care, and transport medicine. There should be nominated senior staff responsible in each referring unit for producing transport protocols, delivering a programme of ongoing education, liaising with receiving centres, and ensuring equipment is maintained serviceable
• Medical escort: the accompanying anaesthetist must be familiar with delivering critical care in a transport environment, with respect to the hazards of equipment failure, tube and line disconnections, acceleration and deceleration forces, and movement artefact on monitors. This is often the senior anaesthetist present in the referring unit; however, the team often faces difficult decisions, as there may be patients requiring ongoing clinical care requiring the senior anaesthetist. It is important that a junior member of the anaesthetic team, with limited transport experience, is not selected to transfer these critically injured patients
• Medical assistant: similarly, experience in functioning in the transport environment is more important than the exact grade or specific profession of the accompanying assistant. It may be that an intensive care or ED nurse, an operating department practitioner, or a critical care paramedic has the most experience with transport processes and equipment, and hence is the most suited team member to accompany the physician
◆ Retrieval team transport: transfer by a specialized retrieval team is associated with improved outcomes for critically injured patients. The rate of adverse clinical incidents on transport, including airway complications, cardiopulmonary arrest, and loss of vascular access, is significantly less (1.5% vs 61%) with a retrieval team vs a non-specialized team transport. Also, illness severity-adjusted mortality is over 50% greater in patients transported by referring hospital teams. Transports by referring hospital teams take around 25% longer, and more critical care interventions are typically required on admission to the receiving unit. Evidence therefore strongly favours the transport of all critically ill patients by retrieval teams; however, within the realm of time-critical neurosurgical transfers, a great deal of contention remains. The Society of British Neurosurgeons suggest that more patients may come to harm waiting on retrieval team transports, although the evidence supporting this statement relates to practice from 20 to 30 years ago. Hence, there is the need for a three-way conversation between the referring unit, the retrieval team, and the neurosurgeon to determine the appropriate transport pathway for the patient, with the ultimate goal being to achieve intracranial decompression as soon as possible, and certainly within 4 hours of injury.
Case update: outlining the principles of equipment for referring team transport
It has been decided that the most time-efficient transport option is for the anaesthetic registrar and an intensive care nurse from the referring unit, both of whom have experience in the transport environment. The patient is presently ventilated in the ED and is clinically stable.
What equipment is required for the safe transport of this patient?
The transport team requires equipment that is able to deliver a mobile intensive care service. This equipment should be pre-identified, specifically detailed for transport, and be regularly checked and maintained. There is no place for assembling transport equipment in an ad hoc fashion, whilst concurrently trying to clinically manage a critically ill patient. There should be a senior clinician nominated in each referring unit who has the responsibility for equipment procurement and maintenance, and liaising with receiving units to ensure collaborative working from transport protocols. The equipment required includes:
◆ Trolley: a unit which has to perform a number of intensive care transports should ideally have a dedicated transport trolley, e.g. the Ferno® CCT6. This allows intensive care equipment, such as pumps, ventilators, and monitors, to be securely mounted, enhancing staff and patient safety and minimizing the risk of damage to this equipment. The critical care trolleys will have a locking mechanism to dock securely to the ambulance chassis, further enhancing patient and staff safety
◆ Monitor: the generic specifications of the monitor require it to be self-powered, with a battery life of several hours, and ideally with spare battery capacity. In addition to meeting all minimal monitoring standards, the monitor must be able to continuously monitor the ETCO2 and at least one invasive pressure, typically arterial. Using invasive, rather than non-invasive, BP monitoring considerably reduces battery power drain and should be utilized on any transfers of critically ill children. Continuous arterial pressure monitoring also allows the immediate detection of a physiological instability that may be invoked, due to acceleration or turning G-forces whilst in motion. The monitor should be mounted on the transport trolley by a secured bracket
◆ Ventilator: transport ventilators are usually relatively simple devices, compared to modern intensive care ventilators; however, they have proven to be robust, waterproof, windproof, and shockproof, and they have the capacity to run for prolonged periods of time without mains power. Options from the Pac and Oxylog series are used widely throughout the UK. The patient should be stabilized on the transport ventilator for some time prior to departure, and ABGs checked to confirm adequate ventilation before moving. Again, there are mounts for both of these types of ventilator for transport trolleys
◆ Oxygen: oxygen supplies should be calculated for the journey, based on current minute ventilation, oxygen requirements, and the anticipated duration of the journey. It is then reasonable to double this calculation to ensure a safety margin. Running out of oxygen during an intensive care transport may lead to patient death and is indefensible. Oxygen will be carried in the ambulance, and it is the transfer team’s responsibility to ensure supplies are adequate before leaving the referring unit. They can be changed easily prior to departure. Oxygen requirements can be estimated by the following formula:
Note that many transport platforms are moving to the newer lightweight style of the oxygen cylinder; for example, the BOC ZF, an F sized cylinder which would normally contain 1300 L of oxygen, but this is compressed to around 250 atm (i.e. around double that of a normal cylinder), so it contains around 2500 L of oxygen, enough for approximately 4 hours of ventilation at an FiO2 of 1.0 in an adult ventilated at 12 x 750 mL.
◆ Pumps: anywhere from three to six infusion pumps will be required for an emergency intensive care transport to infuse sedative and analgesic agents, fluids, vasoactive drugs, and muscle relaxants. Ideally, all of these drugs should be delivered by infusion, rather than boluses, to maintain stability on transfer. The pumps should have a battery life that exceeds the duration of transport, and spare batteries carried where possible. Many modern front-line ambulances have a 12–240 V inverter system where the mains AC power can be delivered from the vehicle’s electrical system when the engine is on, which should be used, wherever possible
◆ Additional equipment and drugs: additional and emergency equipment for airway management, vascular access, and intercostal chest drainage should be carried on all retrievals. Drug bags should include several hours’ supplies of sedation, muscle relaxation, analgesia, and adequate emergency drugs to support arrhythmias or hypotension. These should all be checked as within expiry dates and that all stock is present as part of the transfer equipment routine daily checks.
Case update: outlining the logistical processes for referring team transport
The anaesthetic registrar and the ICU nurse have assembled and checked the transport equipment. The patient has been packaged on a critical care transport trolley, and full invasive monitoring established. He is settled on the transport ventilator, with ABGs confirming satisfactory oxygen and carbon dioxide tensions. Infusions of propofol, alfentanil, and rocuronium are running, and good venous access is secured.
What are the necessary logistical processes to be implemented in order to effectively transfer this patient?
Discussion
◆ Communication:
• Ambulance service: it is vital that all communications with the ambulance service clearly outline that this is a long-distance intensive care transport with a ventilated patient and an accompanying medical team. This may influence the tasking, depending on crew availability and experience and vehicle availability. Some provision for repatriating the transport team to the base hospital should be outlined, particularly where a considerable amount of equipment has been transported, though this should not delay the departure of the team
• Receiving unit: the receiving unit should be called immediately prior to departure to update on the patient’s clinical status and estimated arrival time. The arrival destination should be reconfirmed, e.g. ED, intensive care, or theatre, and, if the team is unfamiliar with the location request, someone from the referring unit should meet the ambulance on arrival. Any specific therapies should be requested, so that they can be made ready in advance at the receiving unit, e.g. drug infusions, blood availability, specific ventilator settings, cooling or warming devices, in order to enhance the efficiency of handover. The transfer team should pass a contact mobile telephone number to the receiving unit
• Relatives: contact details should be taken from the relatives by the transfer team and passed on to the receiving unit. The relatives should be updated on the patient’s clinical condition and the anticipated outline of events and interventions over the subsequent hours. They should be given directions as to where to go and a contact point in the receiving unit, and they must have a clear explanation that they must not attempt to follow the ambulance, as this will risk their own and the patient’s safety
◆ Patient transfers: even for a relatively straightforward road transport, such as this case, there will be a considerable number of intermediate patient moves, each of which poses a risk to the patient’s safety. During loading and unloading of the trolley to and from the ambulance, close attention must be paid by the transport team to the ventilator tubing, drug infusion lines, and monitoring lines, as there is a high chance they might get snagged on various components of the ambulance. Ideally, all tubing and lines should be packaged within the patient’s securing harness, or vacuum mattress if used, to minimize the risk. Outwith specialist transport teams, ambulance service colleagues may not be familiar with moving ventilated patients around; hence, it is vital that the team is vigilant during these periods. As soon as the patient is loaded into the ambulance, the ventilator should be transferred to the ambulance oxygen supply, and, if available, the pumps and monitors powered by the vehicle’s mains AC supply. After every change in oxygen supply, adequate ventilation should be confirmed by patient examination
◆ Handover: copies of all notes and documentation will be provided for the receiving team, and they will have been briefed by the referring unit, but a concise verbal ‘hands-off’ handover should be given by the transport team to everyone in the receiving unit on arrival. Ideally, this should follow an SBAR format and be delivered in 1 minute or less. Assuming the patient is stable, this should be delivered prior to any change of equipment or patient moves. Further detailed questions should be addressed after the handover. An example of an SBAR handover for this patient would be:
• Situation:
‘This is an 11-year-old 40 kg male with an extradural haematoma.’
• Background:
‘He fell off his bike and struck a tree at high speed. Initial GCS was 10 at the scene, deteriorating to 6 by arrival in the ED. He was anaesthetized and transferred for a CT scan. No other injuries or relevant past medical history have been identified.’
• Assessment:
‘He has a 6.5 ETT taped at 17 cm. He is ventilated at a rate of 14 by 400 mL, with an FiO2 of 0.45. The ETCO2 has been between 4 and 4.5 kPa which correlates closely with the arterial PaCO2. The HR has been 80–90, and the MAP at least 80 mmHg. He has two peripheral IVs and a left radial arterial line. Therapies include infusions of propofol at 10 mL/hour and alfentanil at 3 mL/hour. He last had a bolus of rocuronium 20 min ago. There were no major abnormalities on FBC or U&E.’
• Recommendations:
‘He has been stable on transport and is ready for transfer to your operating theatre for haematoma evacuation. He will need a blood cross-match performed urgently. Does anyone have any immediate questions?’
Summary
Evidence indicates that the transfer of critically ill patients is more effectively performed by specialized retrieval teams. However, transport service capacity, logistical issues, or clinical urgency may necessitate transfer by referring unit teams. The complexity of this should not be underestimated, and all units should have dedicated transport equipment that is comprehensively checked on a regular basis, transport protocols, and support from senior staff in the transport process. Clear and concise communication regarding transport planning and handover of patient details will minimize the potential for misunderstanding and errors.
Association of Anaesthetists of Great Britain and Ireland (2006). Recommendations for the safe transfer of patients with brain injury. Available at: <http://www.aagbi.org/sites/default/files/braininjury.pdf>.
Royal College of Anaesthetists (2014). Guidelines on the provision of anaesthetic services. Available at: <http://www.rcoa.ac.uk/system/files/GPAS-FULL-2014_3.pdf>.