Basic Life Support or BLS is that level of medical care for those in a life-threatening situation until the arrival of proper medical care. BLS can be provided either by emergency medical personnel, trained medical professionals or by laymen trained in BLS. The techniques in BLS are mainly focused on airway maintenance, breathing and circulation. Use of automated external fibrillator or AED for defibrillation is a recent advance in BLS and has resulted in improved cardiac survival in cardiac arrest cases.
This new intervention is important because majority of the deaths in cardiac arrest cases are due to ventricular fibrillation which can be reverted using a defibrillator in the electrical phase of ventricular fibrillation. Thus, basic life support consists of chest compressions and ventilations and also early defibrillation. Advanced Life Support or ALS is that form of medical care prior to reaching hospital and which can be delivered only by trained medical personnel or paramedics.
This form of medical care involves many invasive and non-invasive procedures like transcutaneous pacing, intravenous cannulation, cardiac monitoring cardiac defibrillation, intraosseous infusion, needle or surgical cricothyrotomy, , advanced medications through enteral and parenteral routes and endotracheal intubation. Whether BLS or ALS is critical in improving outcomes in cardiac patients is a much debated topic.
According to a multicentric controlled study conducted by Stiell et al (2004) on the benefits of advanced life support in out-of-hospital cardiac arrest patients, advanced life support interventions did not have any added advantage over basic life support. The study revealed that when compared to BLS with rapid defibrillation programs, ALS programs did not have any added benefits. The authors recommended that cardiopulmonary resuscitation by bystanders and rapid-defibrillation responses must be encouraged and should be a priority for EMS resources.
The study concluded that though advanced life support increased the rate of admission to hospital significantly; the rate of survival did not improve, placing more importance on basic life support. In a recent study by Markel et al (2009), the authors aimed to study the outcomes in cardiac arrest patients after they were delivered with basic life support and advanced life support. Their study revealed that BLS-to-ALS survival was an important predictor of survival to hospital discharge.
Every minute of decrease in the arrival of ALS following delivery of BLS was associated with 4% decrease in survival chances. The authors concluded that shorter BLS-to-ALS time is associated with increased survival chances and hence ALS interventions must be utilized for additional benefits. However, the researchers pressed the need for early CPR and defibrillation which is BLS. Different reports were produced by an old study by Bissell et al (1998). This study reviewed extensive literature pertaining to delivery of ALS and BLS to cardiac arrest patients.
Of the 51 articles reviewed, eight articles reported that ALS was in no way better than BLS; seven reported that ALS was effective in some application and the remaining articles concluded that ALS was superior to BLS. The researchers concluded that ALS may be clinically superior to BLS in some patients with certain pathologies. Despite different clinical opinions, it can be said that BLS plays a critical role in the survival chances of a cardiac arrest patient. There are 2 reasons for such an impression. 1. Any bystander can provide BLS if he or she has received some amount of training in BLS.
2. Most of the cardiac arrest cases are due to ventricular fibrillation and defibrillation is “the treatment” for that condition Current studies being conducted into new methods, drugs and/or equipment being studied to improve cardiac survival. Over the past few decades, many new methods, drugs and interventions have been introduced to provide optimum support for patients with cardiac arrest so that the chances of survival are enhanced. Every year, newer approaches are coming up to provide the best possible care for cardiac patients.
This article explores the recent trends in cardiopulmonary resuscitation of cardiac patients in a prehospital setting. Latest international guidelines for cardiopulmonary resuscitation have stressed the need uninterrupted cardiopulmonary resuscitation or CPR so that there is continuous delivery of adequate coronary artery perfusion pressure which is one of the key determinants for return of spontaneous circulation. To facilitate uninterrupted CPR, a new concept of “hands on” defibrillation has been developed.
Research has shown that when CPR is continued with gloved hands during defibrillation, there is absent or minimal shock to the resuscitator (Roppolo et al, 2009). According to the American Heart Association (2005), in children, the chest compressions must be provided at the rate of 100 per minute without any interruption for respiration. According to a study by Bobrow et al (2008), implementation of minimally interrupted cardiac resuscitation increases the survival-to-hospital discharge in those who suffered cardiac arrest out of the hospital.
A recent research proved that ‘noise reduction’ automated external defibrillator and cardiac monitoring analysis can allow certain advanced devices to distinguish a CPR infarct from V-fib (Roppolo et al, 2009). Another new approach aimed at cardiac survival is the cardiocerebral resuscitation or CCR. This method is mainly composed of 3 aspects: continuous chest compression by bystander, new EMS algorithm and vigorous post-resuscitation care. There is no mouth-to-mouth breathing in this approach.
The approach also favours defibrillation, either in the early or late stages (Ewy and Kern, 2009). Recently an automated, load-distributing band chest compression device has been introduced for cardiac resuscitation in a prehospital setting. Ong et al (2006) compared the outcomes of resuscitation between manual and automated cardiac resuscitation. Their study concluded that automated cardiac resuscitation use by EMS is associated with better outcomes. The previous decade has seen much research in the combined use of active compression decompression CPR and impedance threshold device.
Frascone et al (2004) reviewed literature pertaining to this emerging therapy. The authors concluded that use of this new technology should be encouraged as this combination therapy provided optimum vital organ blood flow. References American Heart Association. (2005). 2005 American Heart Association (AHA) guidelines for cardiopulmonary resuscitation (CPR) and emergency cardiovascular care (ECC) of pediatric and neonatal patients: pediatric basic life support.
Pediatrics, 117(5), e989-1004. Bobrow, B. J. , Clark, L. L. , and Ewy, G. A. (2008). Minimally interrupted cardiac resuscitation by emergency medical services for out-of-hospital cardiac arrest. JAMA, 299(10), 1158-65. Bissell, R. A. , Eslinger, D. G. , and Zimmerman, L. (1998). The Efficacy of Advanced Life Support: A Review of the Literature. Prehospital and Disaster Medicine, 13(1), 69- 79. Ewy, G. A. , and Kern, K. B. (2009). Recent advances in cardiopulmonary resuscitation: cardiocerebral resuscitation. J Am Coll Cardiol. , 53(2), 149-57. Frascone RJ, Bitz D, Lurie K. (2004).
Combination of active compression decompression cardiopulmonary resuscitation and the inspiratory impedance threshold device: state of the art. Curr Opin Crit Care, 10(3), 193-201. Markel, D. T. , Gold, L. S. , Farenbuch, C. E. , and Eisenberg, M. S. (2009). Prompt Advanced Life Support Improves Survival from Ventricular Fibrillation. Prehospital Emergency care, 13(3), 329- 334. Ong, M. E. , Ornato, J. P. , Edwards, D. P. (2006). Use of an automated, load-distributing band chest compression device for out-of-hospital cardiac arrest resuscitation.
JAMA, 295(22), 2629-37. Roppolo, L. P. , Wigginton, J. G. , and Pepe, P. E. (2009). Minerva Anesthesiol, 75301-5. Stiell, I. G. , Wells, G. A. , and Field, B. (2004). Advanced Cardiac Life Support in Out-of-Hospital Cardiac Arrest. The New England Journal of Medicine, 351, 647- 656. Appendix Please download articles from these links provided: http://www. ncbi. nlm. nih. gov/pubmed/16651298? ordinalpos=1&itool=EntrezSystem2. PEntrez. Pubmed. Pubmed_ResultsPanel. Pubmed_DiscoveryPanel. Pubmed_Discovery_RA&linkpos=5&log$=relatedarticles&logdbfrom=pubmed