In a study of over 7500 patients with cardiac arrest transported by EMS in the United States, transport distance was not associated with survival on logistic analysis (OR 1.00; 95% CI 0.99–1.01).
A geospatial assessment of transport distance and survival to discharge in out of
hospital cardiac arrest patients: Implications for resuscitation centers
Resuscitation. 2010 May;81(5):518-23
A study using volunteer doctors and nurses in simulated cardiac arrest resuscitations compared three different positions for delivering CPR: standing, kneeling by the patient, or standing on a “taboret”. They measured rescuer fatigue and effectiveness of CPR. They conclude that CPR is best performed in a kneeling position in that it maximizes duration of effective chest compression and minimizes back pain. The authors recommend if two or more experienced healthcare providers are available to perform CPR, alternating rescuers every 2 min in the kneeling or standing on a taboret positions, and every 1min in the standing on the floor position in order to minimize rescuer fatigue.
Rescuer fatigue and cardiopulmonary resuscitation positions: A randomized controlled crossover trial
Resuscitation. 2010 May;81(5):579-84
A study on the early CT appearances of post-cardiac arrest patients shows two signs to be of importance – loss of boundary (LOB) between white and grey matter (at the level of the basal ganglia), and cortical sulcal effacement (SE). These features were more prevalent in patients who had > 20 minutes of arrest time and were associated with a worse neurological outcome at six months.
Early CT signs in out-of-hospital cardiac arrest survivors: Temporal profile and
Resuscitation. 2010 May;81(5):534-8
This is one of those ‘wow they really do that!?‘ papers…Patients undergoing thoracotomy and aortic clamping for pre-hospital blunt traumatic arrest either in the field or in the ED were evaluated for the outcome of survival to ICU admission. None of the 81 patients who underwent this intervention survived to discharge.
Field thoracotomy resulted in shorter times from arrival of the emergency medical team to performance of the thoracotomy (19.2 vs 30.7 mins). Patients who arrested in front of the team had a greater ICU admission rate than those who were already in cardiac arrest when the team arrived (70% vs 8%).
One may argue against an intervention that seems to have resulted in no benefit to the patient. However a counterargument might be that an ICU admission allows for better end-of-life management for grieving families, and for the possibility of organ donation.
Interestingly, there were some neurologically intact survivors of emergency thoracotomy for blunt trauma by this service, although they were excluded from the study for either (i) receiving the field thoracotomy before full arrest or (ii) arresting after arrival in the ED.
Role of resuscitative emergency field thoracotomy in the Japanese helicopter emergency medical service system
Resuscitation. 2009 Nov;80(11):1270-4
37 patients with blunt traumatic cardiac arrest underwent attempted resuscitation by a HEMS crew over a four year period. Chest decompression was performed in 18 cases (17 thoracostomy, one needle decompression). The procedure revealed evidence of chest injury in 10 cases (pneumothorax, haemothorax, massive air leak) and resulted in return of circulation and survival to hospital in four cases. All four cases died of associated major head injury, although one became a heart beating organ donor. Only half of the cases found to have pneumothorax demonstrated clinical signs of one prior to chest decompression.
The authors state: ‘Relying on clinical signs of the thorax alone will not identify all patients with these injuries, and our data support extending the practice into all patients with a suitable mechanism of injury together with external evidence of chest injury.’
Chest decompression during the resuscitation of patients in prehospital traumatic cardiac arrest
Emerg Med J. 2009 Oct;26(10):738-40
A Norwegian randomised controlled trial over five years compared out-of-hospital nontraumatic cardiac arrest outcomes between ACLS protocols with and without access to intravenous drugs (epinephrine/adrenaline, atropine, amiodarone).
Patients randomised to the drug group had a higher rate of hospital admission with return of spontaneous circulation, but there was no significant difference in survival to discharge, survival with favourable neurological outcome, or one year survival.
Intravenous Drug Administration During Out-of-Hospital Cardiac Arrest
JAMA. 2009 Nov 25;302(20):2222-9
A small study of 6 PICU patients requiring CPR for cardiac arrest due to primary cardiac disease showed that blood pressure as measured by an arterial line increased when the depth of chest compression was increased from one third to one half of the chest wall diameter (using the hand-encircling method). Systolic, mean, and pulse pressures increased significantly whereas diastolic blood pressure (a key determinant of coronary perfusion) did not.
Should the ILCOR guidelines be changed to recommend deeper chest compressions? More data are needed, but the take home message here may be that invasive arterial monitoring is a good guide to the effectiveness of CPR during cardiac arrest resuscitation.
Depth of sternal compression and intra-arterial blood pressure during CPR in
infants following cardiac surgery