Only three interventions for cardiac arrest are backed by the literature: early high-quality chest-compressions, early defibrillation, and therapeutic hypothermia.
Wik et al. reported that chest compressions are not delivered for nearly half of the duration of out-of-hospital cardiac arrests, and when performed, compressions are delivered at suboptimal rates and depths.
The proportion of time spent compressing is an easily modified aspect of high-quality cardiopulmonary resuscitation (CPR) and may positively influence patient outcome independent of other known predictors of patient survival to discharge.
High-quality chest compression comprises:
– Appropriate rate (100 per minute)
– Appropriate depth (5 cm or 2 inches), allowing for complete chest wall recoil
– Minimizing periods of interruption
Continuous chest-compression CPR generates the necessary cardio-cerebral perfusion for return of spontaneous circulation (ROSC) and neurologically intact survival at discharge. Christenson et al. demonstrated that the “chest compression fraction” during cardiac arrest is highly prognostic – interruptions in chest compressions decreases the likelihood of survival.
Current recommendations are to stop compressions for no more than 10 seconds during pulse and rhythm check periods as well as for defibrillation if needed. This compression interruption for defibrillation can be decreased by charging the defibrillator during chest compression thereby decreasing “hands off” time required to deliver the defibrillation.
However, the necessity of “hands off” during defibrillation is being challenged. In fact, there is data to suggest current technology makes “hands on defibrillation” both safe and achievable. Biphasic defibrillators with real-time impedance monitoring, adhesive electrodes with more consistent electrode-skin coupling, ECG filtering, and continuous capnography all circumvent the need for rhythm checks and allow for uninterrupted chest compressions.
A 2008 study by Lloyd et al. measured leakage current through mock rescuers performing chest compressions on 43 patients receiving external, biphasic defibrillation. All rescuers were wearing a single pair of polyethylene medical gloves and standing on the patient’s right side. Self-adhesive pads were placed in anteroposterior fashion. Shocks were given at 100J, 200J, and 360J. None of the 43 shocks delivered were perceptible to the mock rescuers. Leakage current for 1 of the 43 exceeded the maximum allowable leakage current for handheld equipment. Leakage current for all 43 was an order of magnitude below the allowable leakage current for non-handheld equipment. There were no adverse events.
There is a technical caveat to this promising practice. A response to this study published by an industry representative notes that while medical gloves do offer high insulation resistance, they are not designed for this purpose and cannot be guaranteed to reliably do so. Double gloving offers further protection but has not been studied.
In summary, for patients receiving external shocks from a biphasic defibrillator, there have been no documented adverse outcomes during continuous compressions provided by a healthcare provider wearing intact gloves. Wearing two sets of gloves likely confers additional protection.
While the presented evidence may convince only the most valiant amongst us to perform continuous compressions during defibrillation, it should assuage skepticism and challenge the notion that defibrillatory shocks cannot be administered simultaneously with chest compressions, possibly obviating the needs for “hands off” compressions altogether.
-- Kunal Sharma, MD and Eric Beck, DO, EMT-P
References:
Christenson J, Andrusiek D, Everson-Stewart S, et al. Chest compression fraction determines survival in patients with out-of-hospital ventricular fibrillation. Circulation; 2009, 120(13):1241-7.
Lloyd MS, Heeke B, Walter PF, and Langberg JJ. Hands-On Defibrillation : An Analysis of Electrical Current Flow Through Rescuers in Direct Contact With Patients During Biphasic External Defibrillation. Circulation; 2008, 117: 2510-2514.
Sullivan JL. Letter by Sullivan Regarding Article, “Hands-On Defibrillation: An Analysis of Electrical Current Flow Through Rescuers in Direct Contact With Patients During Biphasic External Defibrillation.” Circulation; 2008, 118:e712.
Steen S, Liao Q, Pierre L, et al. The critical importance of minimal delay between chest compressions
and subsequent defibrillation: a haemodynamic explanation. Resuscitation; 2003, 58: 249-58.
Wik L, Kramer-Johansen J, Myklebust H, et al. Quality of cardiopulmonary resuscitation during out-of-hospital cardiac arrest. JAMA; 2005, 293(3):299-304.
Wik et al. reported that chest compressions are not delivered for nearly half of the duration of out-of-hospital cardiac arrests, and when performed, compressions are delivered at suboptimal rates and depths.
The proportion of time spent compressing is an easily modified aspect of high-quality cardiopulmonary resuscitation (CPR) and may positively influence patient outcome independent of other known predictors of patient survival to discharge.
High-quality chest compression comprises:
– Appropriate rate (100 per minute)
– Appropriate depth (5 cm or 2 inches), allowing for complete chest wall recoil
– Minimizing periods of interruption
Continuous chest-compression CPR generates the necessary cardio-cerebral perfusion for return of spontaneous circulation (ROSC) and neurologically intact survival at discharge. Christenson et al. demonstrated that the “chest compression fraction” during cardiac arrest is highly prognostic – interruptions in chest compressions decreases the likelihood of survival.
Current recommendations are to stop compressions for no more than 10 seconds during pulse and rhythm check periods as well as for defibrillation if needed. This compression interruption for defibrillation can be decreased by charging the defibrillator during chest compression thereby decreasing “hands off” time required to deliver the defibrillation.
However, the necessity of “hands off” during defibrillation is being challenged. In fact, there is data to suggest current technology makes “hands on defibrillation” both safe and achievable. Biphasic defibrillators with real-time impedance monitoring, adhesive electrodes with more consistent electrode-skin coupling, ECG filtering, and continuous capnography all circumvent the need for rhythm checks and allow for uninterrupted chest compressions.
A 2008 study by Lloyd et al. measured leakage current through mock rescuers performing chest compressions on 43 patients receiving external, biphasic defibrillation. All rescuers were wearing a single pair of polyethylene medical gloves and standing on the patient’s right side. Self-adhesive pads were placed in anteroposterior fashion. Shocks were given at 100J, 200J, and 360J. None of the 43 shocks delivered were perceptible to the mock rescuers. Leakage current for 1 of the 43 exceeded the maximum allowable leakage current for handheld equipment. Leakage current for all 43 was an order of magnitude below the allowable leakage current for non-handheld equipment. There were no adverse events.
There is a technical caveat to this promising practice. A response to this study published by an industry representative notes that while medical gloves do offer high insulation resistance, they are not designed for this purpose and cannot be guaranteed to reliably do so. Double gloving offers further protection but has not been studied.
In summary, for patients receiving external shocks from a biphasic defibrillator, there have been no documented adverse outcomes during continuous compressions provided by a healthcare provider wearing intact gloves. Wearing two sets of gloves likely confers additional protection.
While the presented evidence may convince only the most valiant amongst us to perform continuous compressions during defibrillation, it should assuage skepticism and challenge the notion that defibrillatory shocks cannot be administered simultaneously with chest compressions, possibly obviating the needs for “hands off” compressions altogether.
-- Kunal Sharma, MD and Eric Beck, DO, EMT-P
References:
Christenson J, Andrusiek D, Everson-Stewart S, et al. Chest compression fraction determines survival in patients with out-of-hospital ventricular fibrillation. Circulation; 2009, 120(13):1241-7.
Lloyd MS, Heeke B, Walter PF, and Langberg JJ. Hands-On Defibrillation : An Analysis of Electrical Current Flow Through Rescuers in Direct Contact With Patients During Biphasic External Defibrillation. Circulation; 2008, 117: 2510-2514.
Sullivan JL. Letter by Sullivan Regarding Article, “Hands-On Defibrillation: An Analysis of Electrical Current Flow Through Rescuers in Direct Contact With Patients During Biphasic External Defibrillation.” Circulation; 2008, 118:e712.
Steen S, Liao Q, Pierre L, et al. The critical importance of minimal delay between chest compressions
and subsequent defibrillation: a haemodynamic explanation. Resuscitation; 2003, 58: 249-58.
Wik L, Kramer-Johansen J, Myklebust H, et al. Quality of cardiopulmonary resuscitation during out-of-hospital cardiac arrest. JAMA; 2005, 293(3):299-304.
Defibrillators are widely used devices used at the time of sudden cardiac arrest. A hand on defibrillation process is not entirely safe, but it should be done till the defibrillator is not available as it can save the life of a person as it eliminates the pause of defibrillation process.
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