The International Liaison Committee on Resuscitation has published its five-yearly update of resuscitation guidelines.
The American Heart Association Guidelines can be accessed here
The European Resuscitation Guidelines can be accessed here
2010 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science
Circulation. 2010;122:S639
I have always had a problem with the ATLS classification of hypovolaemic shock, and omit it from teaching as any clinical applicability and reproducibility seem to be entirely lost on me. I was therefore reassured to read that real physiological data from the extensive national trauma registry in the UK (TARN) of 107,649 adult blunt trauma patients do not strongly support this classification. A key observation we regularly make in trauma patients is the frequent presence of normo- or bradycardia in hypovolaemic patients, which is well documented in the literature.
Unreferenced dogma that became viral
An excellent discussion section in this paper states: ‘it is clear that the ATLS classification of shock that associates increasing blood loss with an increasing heart rate, is too simplistic. In addition, blunt injury, which forms the majority of trauma in the UK, is usually a combination of haemorrhage and tissue injury and the classification fails to consider the effect of tissue injury‘
Testing the validity of the ATLS classification of hypovolaemic shock
Resuscitation. 2010 Sep;81(9):1142-7
Aeromedical retrieval specialists in Scotland developed a simple, cheap, effective in-flight cooling protocol using intravenous (IV) cold Hartmann’s solution and chemical cooling packs. Fluids cooled in a fridge (4°C) were transported in an insulated cool box; the patient was sedated, paralysed and intubated, and controlled ventilation started. The patient was then cooled by IV infusion of 30 ml/kg of cold Hartmann’s. Chemical ice packs were activated and placed in the axillae and groin. The time interval between successful resuscitation and the patient being retrieved and flown to an Intensive Care Unit (ICU) was at least 3.5 h. Cooled patients had a mean decrease in body temperature during retrieval compared to patients not cooled (−1.6 °C vs. +0.9 °C, p = 0.005) and a lower body temperature on ICU arrival (34.1 °C vs. 36.4 °C, p = 0.05). Two of the 5 cooled patients achieved target temperature (<34 °C) before ICU arrival. No complications of in-flight cooling were reported.
Not the only way to cool down in Scotland
In-flight cooling after out-of-hospital cardiac arrest
Resuscitation. 2010 Aug;81(8):1041-2
Emergency physicians at Hennepin County Medical Centre (HCMC) are trained in skull trephination (drilling a burr hole) for patients with coma, anisocoria and epidural (extradural) haematoma (EDH) who have not responded to osmotic agents and hyperventilation. This may be particularly applicable in centres remote from neurosurgical centres where delays caused by interfacility transfer are associated with increased morbidity and mortality.
Dr Smith and colleagues from HCMC describe a series of five talk-and-deteriorate patients with EDH who underwent skull trephination. 3 had complete recovery without disability, and 2 others had mild to moderate disability but with good to excellent cognitive function. None had complications from the procedure other than external bleeding from the already lacerated middle meningeal artery. In 4 of 5 cases, the times were recorded. Mean time from ED presentation to trephination was 55 min, and mean time from ED to craniotomy was 173 min. The mean time saved was 118 min, or approximately 2 h.
All trephinations were done by emergency physicians, who had received training in skull trephination as part of the HCMC Emergency Medicine Residency or as part of the Comprehensive Advanced Life Support (CALS) course. Training was very brief and involved discussion of the treatment of EDH, review of a CT scan of EDH, and hands-on practice on the skull of a dead sheep, using the Galt trephinator.
An excellent point made by the authors reminds us that patients with EDH who talk-and-deteriorate (those with the traditionally described “lucid interval”) have minimal primary brain injury and frequently have no brain parenchymal injury. Thus, if the EDH is rapidly decompressed, the outcome is significantly better than for deterioration due to other aetiologies. The authors recommend in EDH that the procedure should be done within 60–90 min of onset of anisocoria. A review of other studies on the procedure would suggest that case selection is critical in defining the appropriateness of the procedure: talk-and-deteriorate, coma, anisocoria, and a delay to neurosurgical decompression.
Emergency Department Skull Trephination for Epidural Hematoma in Patients Who Are Awake But Deteriorate Rapidly
J Emerg Med. 2010 Sep;39(3):377-83
Over a thousand patients in North America with blunt traumatic head injury and coma who did not have hypovolaemic shock were randomised to different fluids pre-hospital. 250 ml Hypertonic (7.5%) saline was compared with normal (0.9%) saline and hypertonic saline dextran (7.5% saline/6% dextran 70). There was no difference in 6-month neurologic outcome or survival.
Out-of-Hospital Hypertonic Resuscitation Following Severe Traumatic Brain Injury
JAMA. 2010;304(13):1455-1464.
Using Poiseuille’s law and standardized gauge sizes, an 18-gauge (g) intravenous catheter (IV) should be 2.5 times faster than a 20-g IV, but this is not borne out by observation, in vitro testing, and manufacturer’s data. A nice simple study on normal volunteers compared simultaneous flow rates between a single 18G iv in one arm with two 20G ivs in the other arm. The two smaller ones provided significantly faster flow than the single larger one, although flow rates were slower than manufacturer’s estimates. This is in keeping with this other study on cannula flow rates.
Are 2 smaller intravenous catheters as good as 1 larger intravenous catheter?
Am J Emerg Med. 2010 Jul;28(6):724-7
A cadaveric study using a 3-dimensional electromagnetic tracking device to asses cervical motion compared the application of a scoop stretcher with two other manual transfer techniques, including log rolling onto an extrication (spine) board. The scoop method restricted cervical spine movement more than log rolling, although this was not statistically significant.
The authors conclude: the effectiveness of the scoop stretcher to limit spinal motion in the destabilized spine is comparable or better than manual techniques currently being used by primary responders.
Are scoop stretchers suitable for use on spine-injured patients?
Am J Emerg Med. 2010 Sep;28(7):751-6
An Australian randomised controlled trial assessed the effect of pre-hospital cooling (using 2 litres ice cold Hartmann’s) of post-cardiac arrest patients on functional status at hospital discharge. The intervention group were marginally cooler on arrival but did not have improved outcomes.
The authors conclude: In adults who have been resuscitated from out-of-hospital cardiac arrest with an initial cardiac rhythm of ventricular fibrillation, paramedic cooling with a rapid infusion of large-volume, ice-cold intravenous fluid decreased core temperature at hospital arrival but was not shown to improve outcome at hospital discharge compared with cooling commenced in the hospital.
Induction of Therapeutic Hypothermia by Paramedics After Resuscitation From Out-of-Hospital Ventricular Fibrillation Cardiac Arrest
Circulation. 2010 Aug 17;122(7):737-42 Free Full Text
One issue from this study was that relatively short urban pre-hospital transport times meant some patients did not get the full two litres, and some had already received room temperature fluids during the cardiac arrest resuscitation. The authors suggest further study should involved initiating cooling during the arrest. In fact a European study has done just that, using a device call a RhinoChill (a portable transnasal cooling device) to lower temperature during arrest in a randomised controlled trial. This trial showed pre-hospital intra-arrest transnasal cooling is safe and feasible and is associated with a significant improvement in the time intervals required to cool patients.
Intra-arrest transnasal evaporative cooling: a randomized, prehospital, multicenter study (PRINCE: Pre-ROSC IntraNasal Cooling Effectiveness)
Circulation. 2010 Aug 17;122(7):729-36
A thought provoking article in Critical Care Medicine outlines basic science, animal, and human studies that suggest oestrogen may have a protective effect in a wide range of critical illnesses from cardiac arrest to trauma to stroke. It urges clinical trials of sex hormones, some of which are underway. Regarding traumatic brain injury, the authors state: “To date, studied interventions to treat the effects of secondary injury, such as induced hypothermia or sedative-hypnotic coma, have had disappointing results… Clearly, EMS (or emergency department) infusion of a single IV bolus of estrogen, a therapy shown in the laboratory to be a strong, direct, easy-to-deliver antioxidant, antiapoptotic, and anti-inflammatory intervention, has a much better chance of decreasing the severity of injury.”
Bold? Let’s see if studies such as this one show this intervention to be so beneficial.
Rationale for routine and immediate administration of intravenous estrogen for all critically ill and injured patients
Critical Care Medicine. 38(10):S620-S629, October 2010
Being human, I suffer from confirmation bias: I’ve become aware that I’m always on the look out for studies that show benefit from physician-provided pre-hospital care and therefore it’s possible I miss the ones that show no benefit. Of course, no ‘level 1’ evidence is out there yet. This study isn’t hugely impressive, but worth adding to the list. After adjusting for injury severity, trauma patients treated on scene by Dutch physicians had no difference in mortality compared with those that received standard care. In the subgroup analysis for patients with severe traumatic brain injury, the mortality rate with physician involvement was lower than that without, but was not statistically significant. On scene times averaged 2.7 minutes longer in the physician group although factors that might have contributed to this, such as entrapment or on scene interventions, were not recorded.
A Dutch Doctor
The Association of Mobile Medical Team Involvement on On-Scene Times and Mortality in Trauma Patients
J Trauma. 2010 Sep;69(3):589-94
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