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Human factors in complex trauma S Mercer MBChB MAcadMEd FHEA FCollT FRCA MMEd C Park MBE FRCA FFICM DipIMC DipRTM RAMC Matrix reference 1I02, 1I03 NT Tarmey FRCA DICM DipIMC RCS(Ed) RAMC 2A02, 2A05, 3A10 Key points Human factors are now integrated into everyday article will focus on a typical complex civilian anaesthetic practice, as a result of the work per- trauma case (described in Box 1) arriving in a Downloaded from https://academic.oup.com/bjaed/article/15/5/231/240545 by guest on 11 June 2021 Exemplary human factors formed over a decade ago looking at anaesthetists UK Major Trauma Centre and will demonstrate are vital to the timely 1 assessment and treatment of non-technical skills (ANTS). Much of this work how lessons learnt by the UK-DMS are now was performed after key publications in the USA2 being translated into civilian practice. a complex trauma patient. 3 The designation of a trauma and the UK highlighting that human error and system design was responsible for patient harm. team leader allows a ‘hands Subsequent high profile cases relevant to anaes- Preparing the team off’ coordination of trauma 4,5 team activity and thesia have brought to light where human Usually, there is a prehospital alert from the maintenance of situational factors failures have led to patient death. In 2010trauma scene and the trauma team is activated awareness. the Royal College of Anaesthetists dedicated the 10 min before the estimated time of arrival. Maintaining situational entire Anniversary Meeting to Human Factors The composition of a typical UK civilian trauma and published a supplement to the British Journal awareness allows an early team is listed in Table 2. Many NHS trauma reaction to changing of Anaesthesia. Some of the human factors related teams are now led by a consultant (usually physiology. to the trauma team are listed in Table 1. Emergency Physician) and will have activation 6 Communication is vital and The 2007 report ‘Trauma: Who Cares?’ criteria to ensure that the team is only mobilized can be facilitated by regular highlighted the deficiencies in the delivery of when required. This is based on the mechanism trauma care in the UK, some of which resulted updates or ‘sit reps’. of injury, anatomy, and physiology. Typical acti- Followership is essential to from failures in decision-making, communica- vation criteria are listed in Table 3. tion, and team-work. Following on from this By ensuring that the trauma team arrives the functioning of the complex trauma team. report, there has been the development of trauma before the patient, the trauma team leader (TTL) is centre networks around the country and a per- given the opportunity to brief the team. This ceived improvement in trauma care delivery. allows a projection of mental models of what The UK Defence Medical Services (UK-DMS) the likely clinical sequence is going to be, promot- S Mercer MBChB MAcadMEd FHEA have attributed much of the success of their ing good followership. During the preparation FCollT FRCA MMEd trauma 7are in Afghanistan to exemplary human phase, there is the opportunity to check equipment Royal Navy Consultant Anaesthetist factors, particularly in the organization, brief- and draw up expected drugs. The anaesthesia team Anaesthetic Department ing, and co-ordination of the trauma team. This often has a ‘wet pack’ of intubation drugs, Aintree University Hospital Liverpool L9 7AL UK Tel: þ44 7970153168 E-mail: simonjmercer@hotmail.com (for correspondence) Box 1 Clinical case C Park MBE FRCA FFICM DipIMC Injury at 20:10 DipRTM RAMC A 25-yr-old male was cycling home in central London when he was hit by and dragged under the Consultant in Anaesthesia, Intensive Care and Pre-Hospital Care wheels of an articulated lorry as it was turningelt. He had been cycling along on the inside of the lorry, and had gone underneath the rear axle as it turned. Kings College Hospital and London’s Air Ambulance He was managed on scene by two London Ambulance Service Paramedic Crews, and an London ex-Helicopter Emergency Medical Service (HEMS) team paramedic. HEMS were requested but UK were on another mission. NT Tarmey FRCA DICM DipIMC The patient was not trapped, and sowas pulled out from under the lorry, with ‘manual in-line stabil- RCS(Ed) RAMC ization’in situ and then a cervical-spine collar, orthopaediccoop stretcher, and pelvic binder were Consultant in Critical Care and Anaesthetics applied. Oxygen was administered via a 15 litre ‘non-rebreather’ face mask and i.v. access was Queen Alexandra Hospital Portsmouth obtained with 16 G cannula in the left ante-cubital fossa. One gram of tranexamic acid was given. The Portsmouth patient was agitated and in pain and was given 10 mg orphine i.v., before being transported to the UK nearest major trauma centre. Page 1 of 6 doi:10.1093/bjaceaccp/mku043 Continuing Education in Anaesthesia, Critical Care & Pain | 2014 & Crown copyright 2014. Human factors in complex trauma analgesia, antibiotics, and key trauma drugs such as tranexamic acid. visible catastrophic haemorrhage then the patient should not be Contingency plans are discussed such as dealing with a difficult touched until the handover is completed. This ensures that everyone in airway) and telephone alerts are made to the operating theatre (OT), the trauma team is aware of the handover and can start the resuscita- radiology, and transfusion. tion ‘on the same page’. The UK-DMS use the acronym ‘AT-MIST’, On arrival at hospital, it is important that the handover is con- standing for Age, Time of injury, Mechanism of injury, Injuries sus- ducted in silence. Unless there is an impending airway problem or tained, and Treatment given. This is described inBox 2 for the example patient. Table 1 Typical human factors relevant to the trauma team Human factor Example Table 3 Trauma team activation criteria (taken from Kings College Hospital, Major Downloaded from https://academic.oup.com/bjaed/article/15/5/231/240545 by guest on 11 June 2021 Leadership In the trauma theatre, the anaesthetist is handed over the role ofrauma Service: Information for Members of the Trauma Team). This will apply to patients arriving at the hospital or who have a prehospital alert leader from the TTL. In complex trauma, there are often several surgical teams working at once and so this requires co-ordination particularly in the timings of tourniquet release 1. Traumatic event and one of the following: Situational The TTL should be ‘hands off’ as this allows them to maintain an † Oxygen saturation ,90% awareness ‘all round look’ (some people ask ‘who is driving the bus?’). † Systolic arterial pressure ,90 mm Hg Initial information will come from the patient’s handover from † Respiratory rate ,9or .29 bpm the paramedics, primary survey, monitoring, and initial tests such† GCS ,14 as venous blood gas 2. Penetrating injury to Team-working The trauma team is a large, resource-rich unit and it is important † Head that activity is coordinated with members performing as a team † Neck and not as individuals † Chest Followership Other members of the trauma team are ‘followers’ and must † Abdomen anticipate changing situations in the trauma bay. This might † Pelvis include preparing equipment, making phone calls to order tests † All gunshot wounds or making suggestions to the team leader 3. Fractures Communication There is the potential in a serious trauma for the noise levels to be† Open or depressed skull fractures raised. The TTL must ensure that noise is kept to a minimum to † Pelvic fracture avoid communication failures. It is also important that † Two or more proximal long bone fractures observations and administered drugs are verbalized so that the † Flail chest team leader and scribe are aware 4. Traumatic amputation 5. Blast or crush injury 6. Major burns Table 2 Composition of a typical trauma team in an NHS major Trauma centre. ED, † 10% total body surface area but lower threshold in child or elderly emergency department; ST, speciality trainee; HCA, healthcare assistant † Combination of burns and trauma 7. Road traffic crash † High speed crash (.30 mph) or pedestrian vs vehicle at .20 mph † Trauma team leader (ED consultant) † Primary survey doctor (ED SpR) † Separation of rider and bike † Anaesthetist 1 (ST4–7) † Intrusion into passenger compartment † Ejection from vehicle † ODP † Scribe (trauma nurse coordinator) † Death in the same passenger compartment † ED nurse 1 (circulator) † Bull’s eyed windscreen † 20 min extrication time † ED nurse 2 (rapid infuser) † ED nurse 3 (rapid infuser) 8. Falls † Runner (HCA) † Height of .3m † Paediatrics—consider the age and height of the child in relation to the height † Orthopaedic surgeon (ST4–7) † General surgeon (ST4–7) fallen † Radiographer 9. HEMS transfer 10. Drowning/submersion Box 2 Handover: AT-MISTon arrival at 21:00 r yA2 T 20:10 M Cyclist vs lorry I R-sided chest injury, abdominal distension and tenderness, and probable pelvic fracture S SpO82%, airway patient, respiratory rate 35, heart rate 130, no radial pulse present, agitated, GCS 13, moving all four limbs, in pain. T 15 litre O 2 c-spine collar, orthopaedic scoop stretcher, pelvic binder, 16 G i.v. access in left ante-cubital fossa, 1 g tranexamic acid, 10 mg morphine i.v. Page 2 of 6 Continuing Education in Anaesthesia, Critical Care & Pain j 2014 Human factors in complex trauma Box 3 Management in the ED. *Ketamine used as an induction agent has gained popularity for haemodynamically compromised patients. It allows a more cardiovascularly stable anaesthetic when compared with other drugs such as propofol or thiopental † 2 units of red blood cells (RBC) given immediately via i.v. in ACF 21 21 21 † RSI with 1 mg kg ketamine*, 1 mgkg fentanyl, and 1 mg kg rocuronium † Immediate bilateral thoracostomies (large amount of airand some blood release on right). Intercostal chest drains sited † Subclavian central venous line (8.5 Fr) sited on right Downloaded from https://academic.oup.com/bjaed/article/15/5/231/240545 by guest on 11 June 2021 † RBC switched to central line, and 2 further units given † Code Red pack A arrived from transfusion and fresh-frozen plasma started † Second tranexamic acid dose of 1 g started as infusion † CT scan urgently requested and transferred with Belmont Rapid Infuser (Belmont Instrument Corporation, Boston, MA, USA) running throughout. Management in the emergency department Table 4 An example of Code Red ‘shock pack’ contents Pack A Pack B The initial management in the emergency department (ED) is described in Box 3. 4 RBC 6 RBC 4 FFP 4 FFP Cryopreciptate, 1 adult therapeutic dose (2 pools of 5 units) Situational awareness and the trauma team Platelets, 1 adult therapeutic dose The complex trauma patient described in Box 1 requires a full trauma team response and the potential for the clinical condition to least 2 units of red blood cells (RBC) available, but the initial worsen demands exceptional situational awareness. Having a desig- massive haemorrhage protocol should also initiate ‘shock packs’ in- nated senior TTL allows one person, who should remain ‘hands-off’ cluding clotting products. These may vary in different hospitals but the patient, to retain an overall situational awareness. One commonly are likely to contain products as in packs A and B described in accepted definition of situational awareness is ‘the perception of ele- ments in the environment within a volume of time and space, the Table 4. Where a HEMS team is in attendance on scene, they will declare a ‘Code Red’ as soon as possible to the receiving ED, and comprehension of their meaning, and the projection of their status in may also give prehospital red cell transfusion. the near future’, and this accurately describes how the TTL should be thinking throughout the assessment in the trauma bay. Although The optimal ratio of blood product transfusion in traumatic haemorrhage is still being investigated, but the current UK-DMS the TTL has overall responsibility for the team response, the anaes- 11 thetist also has an important responsibility. They must advise the massive haemorrhage protocols have been summarized recently. The main aim should be to achieve identification of bleeding points TTL, provide relevant information at an appropriate time for it to be and therefore source control as quickly as possible while replacing received, and assist with the decision-making process. the products that are being lost. It is vital that the decision-making process around bleeding control is made swiftly and has senior input Damage control resuscitation to ensure that there are no prolonged delays in treatment. The concept of damage control resuscitation includes haemostatic resuscitation and identification of injuries and therefore the source of bleeding to achieve haemorrhage control. 10Resuscitation to nor- The trauma team anaesthetist motension is necessary after haemorrhage control in order to The trauma team anaesthetist must make their own assessment of the achieve adequate peripheral tissue perfusion. This process requires patient’s physiology and injuries in order to decide on the most ap- the activation of a massive transfusion protocol and communication propriate time to perform a rapid sequence induction (RSI) of anaes- with the transfusion laboratory. In many trauma centres, the term thesia and also to guide the haemostatic resuscitation. Deciding ‘Code Red’ is used to indicate a patient with major haemorrhage whether to go to the CT scanner, the angiography suite or the OTs who requires the massive transfusion protocol to be activated. Code next will be part of this decision-making process. This requires the Red activation criteria include a systolic arterial pressure ,90 mm anaesthetist to have good situational awareness regarding the state of Hg (at any time), patients who are non-responders to fluid boluses the patient’s physiology and the injuries that are being identified. As and suspected or confirmed haemorrhage. All EDs should have at the trauma anaesthetist, there are a number of pitfalls that can occur Continuing Education in Anaesthesia, Critical Care & Pain j Page 3 of 6Human factors in complex trauma due to poor human factors in the ED phase. These are summarized anaesthetist, it is easy for your ‘bandwidth’ (i.e. your available in Table 5. mental capacity) to become overloaded by a very sick patient requir- The patient described in Box 1 has increased respiratory effort, ing immediate multiple interventions. Recognition of this possibility low oxygen saturations, and a pneumothorax on the right. He and effective utilization of other team members is essential during requires intubation immediately to improve oxygen delivery and to the RSI. reduce the work of breathing. The patient’s response to blood prod- Trauma patients requiring emergency intubation with simultan- ucts must be closely observed in order to guide therapy and identify eous resuscitation have ‘a lot going on’ around them to cause distrac- whether he is responding to the resuscitation or is still actively tion during the RSI. The option to wake if intubation fails, as 12 bleeding. The primary survey is conducted simultaneously and is described in the Difficult Airway Society Guidelines, is not appro- 8 coordinated by the TTL. Concurrent activity is required, ideally priate when they require ongoing resuscitation and immediate surgi- Downloaded from https://academic.oup.com/bjaed/article/15/5/231/240545 by guest on 11 June 2021 with one anaesthetist inserting large-bore central access such as an cal intervention. Based on collective experience and published 8.5 Fr ‘trauma line’ into the subclavian vein in order to rapidly literature, 13 the UK-DMS have taken a default position of securing infuse the blood products, while the other anaesthetist prepares to the airway in the majority of trauma patients requiring RSI with a perform the RSI. Macintosh size 4 laryngoscope blade and a gum-elastic bougie with In the ideally staffed trauma team, there should be two anaesthe- two suction devices close to hand. No more than three attempts at in- tists for ‘Code Red’ patients such as this to enable one to focus on tubation (with re-oxygenation in between attempts) are permitted central access and blood product replacement, while the other before clear communication of failed intubation with immediate pro- manages the airway and ventilation. However, this is often not pos- gression to a surgical airway. RSI in trauma will usually require sible, even in many major trauma centres. As the sole trauma manual in-line stabilization and must be performed in a ‘sterile cockpit’, that is, there should be silence during the RSI to allow Table 5 Pitfalls for the trauma anaesthetist in ED. TTL, trauma team leaEer;, full concentration and identification and communication of prob- CO2 lems. 12 The anaesthetist must allocate roles to the team as listed in end-tidal carbon dioxide measurement (measured by caponography) Table 6, while the TTL provides situational awareness to avoid fix- Pitfall Measures to mitigate risk ation errors. Not hearing handover Do not transfer ventilator or check tracheal tube during the prehospital handover: do it before or afterwards Not anticipating injuries sustained Understand the mechanism of injury and therefore potential injuries sustained Table 7 The command huddle for critical decision-making in ED. IR, interventional Lack of situational awareness Understand the physiology of the patient, radiology especially respiratory and cardiovascular Key people status, and listen to the TTL’s plans. Be ED TTL aware that when your ‘bandwidth’ is overloaded you may not hear everything † Provides overall leadership and situational awareness, including an understanding of the resources available Poor followership Ensure that information is delivered to the TTL Lead surgeons (ideally general surgery and orthopaedics) when they are ‘ready to receive’ it. Important information will not be heard or † Provide expert assessment of the injuries found, surgical options available, and priorities for surgical treatment interpreted if delivered in the wrong way at Lead anaesthetist the wrong time † Provides expert assessment of physiological stability, response to transfusion, Confusion over roles during RSI Clearly allocate roles during preparation for and priorities for airway management RSI Key decisions Omission of important equipment Use a checklist, especially if assistant is not Treat here or transfer to another hospital? during RSI (e.g.ECO2) regularly assisting at intubations Lack of situational awareness during Use assistant and TTL as your eyes and ears † Does our hospital have the resources and expertise to manage this case safely? † What are the relative risks of transferring to a specialist centre vs treating here? RSI during intubation. This prevents task RSI in ED or in the OT? fixation Attempted insertion of an arterial linThis does not improve the arterial pressure, it † How great is the risk of airway obstruction or respiratory failure before reaching the OT? when the arterial pressure is very low just delays surgical intervention and causes † How much safer is it to anaesthetize this patient in the OT vs ED? loss of situational awareness. The arterial † Will this patient be able to tolerate the move to CT/OT without anaesthesia? line can be sited once the patient is on the operating table CT first or straight to OT or IR? † How much delay will be caused by getting a CT before surgery? † Is the patient stable enough to tolerate this delay? † How likely is it that the CT results will alter this surgery? If straight to OT, which body cavity should be opened first? † Where does the most time-critical injury seem to be? Table 6 Team roles for RSI † Is it possible to get proximal control of any bleeding? Manual in-line stabilization If pelvic or stab wound arterial bleeding is IR more appropriate than OT? Cricoid pressure/laryngeal manipulation † Is it arterial bleeding that is not likely to respond to packing? † Is there concurrent intra-abdominal bleeding requiring laparotomy? Drug administration Intubation IR, interventional radiology. Page 4 of 6 Continuing Education in Anaesthesia, Critical Care & Pain j 2014 Human factors in complex trauma Decision-making Box 4 CT scanner information The time spent in ED is important, but it is only a step towards more Injuries identified on CT definitive investigations and treatment. A successful ED phase will † Bilateral rib fractures result in the patient exiting the department quickly, with a tolerable † Flail chest posteriorly on right (ribs 2–8) degree of physiological stability, for timely and appropriate investi- † Single rib fractures posteriorly on left (ribs 3–7) gations and/or surgery. † Grade 5 liver laceration, actively extravasating The end of the ED phase is a time when critical decisions about † Unstable open pelvic fracture, activelyextravasating further investigations, treatment, and transfer must be made. These decisions need a combined approach from at least three senior Downloaded from https://academic.oup.com/bjaed/article/15/5/231/240545 by guest on 11 June 2021 members of the team: the TTL; the lead surgeon(s); and the lead anaesthetist. In the UK-DMS, this short meeting is known as the Box 5 Summary of treatment up 14 ‘Command Huddle’. Key decisions that must be made at this to arrival at the OT (21:30) stage are shown in Table 7. For timely and effective decisions Total transfusion 8 RBC and 4 FFP (with next 4 FFP en route to be made, these people must be present in person and must have to the OT from blood bank) sufficient seniority to make difficult decisions. Attempting to Anaesthesia maintained with 1% propofol infusion at make do with junior staff in ED and telephone communication 8mlh 21 and midazolam boluses with remote consultants can only increase the risk of delayed and AP 90/60 but only maintained while actively infusing blood inappropriate care. products The patient described in Box 1 is transferred to the CT scanner and the information obtained is shown in Box 4. He is immediately HR 120 Weakly palpable radial pulses transferred to the OT with a summary of treatment described in Box 5 and further interventions in Box 6. Box 6 Summary of treatment up to Team working handover in the critical care unit On transfer from ED to the OT, team leadership for the resuscita- OT interventions tion will move from the ED TTL to the lead anaesthetist. This tran- Trauma laparotomy and packing to the liver sition of responsibility comes at a busy time for the anaesthetist Retroperitoneal packing and must be managed carefully to avoid errors. The safest solution External fixation of the pelvis is probably for the ED TTL to stay with the team and in control Ongoing blood product requirements despite the above proce- until the patient is safely positioned and established on the ventila- dures so progression to interventional radiology for embolization tor in the OT. of a branch of the right internal iliac artery. On arrival in the OT, it is important to ensure that the whole team Transfer to critical care are aware of the clinical situation and surgical plans. This concise update, which can be combined with the WHO Checklist, is known Table 8 Human factors pitfalls during trauma surgery Pitfall Measures to mitigate risk Unnecessary conflict over basic principles and processes (e.g. refusal of blEstablish clear guidelines and standard operating procedures, supported by training and issue sufficient quantities of blood and clotting products) multi-speciality involvement Lack of clear leadership (e.g. three anaesthetists working together, but noState clearly the name of the lead anaesthetist to the whole OT team. When other with overall situational awareness) anaesthetists come to help, establish defined roles for each anaesthetist Becoming task-focused (e.g. an anaesthetist becoming fixated on inserting anMaintain ‘hands-off’ leadership of the anaesthetic when sufficient assistance is or a surgeon becoming fixated on one small aspect of the surgery) available. Delegate technical tasks to other team members Not communicating effectively (e.g. an anaesthetist and surgeon both aware Ensure whole team is aware and prepared for critical moments including: problems but not of each other’s) † clamps or tourniquets going on or off † packing or mobilizing large structures (e.g. liver, lung, or heart) 14 Use brief, regular, structured, situational reports (‘sit-reps’)team, including: † Time spent in OT † Clotting and transfusion totals † Physiological status (including temperature and acidosis) † Surgical findings, progress, and future intent Continuing Education in Anaesthesia, Critical Care & Pain j 2014Page 5 of 6Human factors in complex trauma by the UK-DMS as the ‘Snap Brief’. 14The key points of informa- References tion that must be communicated include: 1. Fletcher G, McGeorge P, Flin RH et al. The role of non-technical skills † the main injuries found on CT and clinical examination; in anaesthesia: a review of current literature. Br J Anaesth 2002; 88: † the physiological status and degree of stability; 418–29 2. Kohn LT, Corrigan JM, Donaldson MS, eds. To Err Is Human: Building a Safer † the transfusion given up to this point, ongoing requirements, and Health System. Washington: National Academies Press, 2000 degree of coagulopathy (including results of near-patient testing w 3. Department of Health. An Organisation with a Memory. London: The such as RoTEM ); Stationery Office, 2000: VII–XI † the surgical plans and expected timescale of the operation. 4. The case of Elaine Bromiley. Available from http://www.chfg.org/resources/ 07_qrt04/Anonymous_Report_Verdict_ and_Corrected_Timeline_Oct_ During trauma surgery, there are a number of human factors-related 07.pdf (accessed 17 January 2014) Downloaded from https://academic.oup.com/bjaed/article/15/5/231/240545 by guest on 11 June 2021 pitfalls that must be avoided. A summary of the key risks and mea- 5. Sheriffdom of Glasgow and Strathkelvin under the Fatal Accidents and sures that may be taken to mitigate them is shown in Table 8. Sudden Deaths (Scotland) ACT 1976. Determination of Sheriff Linda The transition to postoperative critical care is unique in the Margaret Ruxton in Fatal Accident Inquiry into the death of Gordon Ewing. Available from http://www.scotcourts.gov.uk/ opinions/2010FAI15. process so far, in that there is usually enough time for proper plan- ning and handover. The opportunity should be taken to engage with html (accessed 17 January 2014) 6. National Confidential Enquiry into Patient Outcome and Death. Trauma: the intensive care unit at the earliest opportunity. This ensures that Who Cares? London: NCEPOD, 2007 appropriate resources can be made available and will allow a thor- 7. Midwinter MJ, Mercer S, Lambert AW et al. Making difficult decisions in ough handover to the receiving clinicians (ideally in the OT) for major military trauma: a crew resource management perspective. J R Army seamless continued care. Med Corps 2011; 157: S299–304 8. Smith J, Russell R, Horne S. Critical decision-making and timelines in the emergency department. J R Army Med Corps 2011; 157: 273 Summary 9. Endsley MR. Toward a theory of situation awareness in dynamic systems. Hum Fact 1995; 37:32–64 The establishment of major trauma centres around the UK has led to 10. Jansen JO, Thomas R, Loudon MA et al. Damage control resuscitation for the concentration of trauma experi ce in key hospitals. Human factors patients with major trauma. Br Med J 2009; 338: 1778 such as communication, situational awareness, team working, and 11. Mercer SJ, Tarmey NT, Woolley T et al. Haemorrhage and coagulopathy decision-making are all key to the timely assessment and treatment in the defence medical services. Anaesthesia 2012; 68:49–60 of a complex trauma patient. This article describes some of the key 12. Mercer SJ, Tarmey NT, Mahoney PF. Military experience of human factors human factors required by the trauma team with notorious pitfalls in airway complications. Anaesthesia 2013; 68: 1080–1 and strategies to avoid them. 13. Mercer S, Lewis S, Wilson S et al. Creating airway management guidelines for casualties with penetrating airway injuries. JR Army Med Corps 2010; 156: S355–60 14. Arul GS, Pugh H, Mercer SJ et al. Optimising communication in the Declaration of interest damage control resuscitation-damage control surgery sequence in major None declared. trauma management. J R Army Med Corps 2012; 158:82–4 Page 6 of 6 Continuing Education in Anaesthesia, Critical Care & Pain j 2014