Evaluation of SC-V Versus Conventional CPR
Condition: Arrhythmia; Cardiovascular Diseases; Heart Arrest; Heart Diseases; Myocardial Infarction; Ventricular Fibrillation; Cerebral Anoxia
MeSH terms: Hypoxia, Brain; Cardiovascular Diseases; Heart Diseases; Myocardial Infarction; Ventricular Fibrillation; Heart Arrest; Infarction
Study type: Interventional
Phase: Phase 3

Summary: 
      To assess the benefits of a new method of cardiopulmonary resuscitation, SC-V CPR
      (simultaneous compression and ventilation CPR) in terms of short and long-term survival and
      lessened cerebral dysfunction.
    

Detailed description: 
      BACKGROUND:

      Since the 1960's, developments in cardiopulmonary resuscitation have resulted in the savings
      of countless numbers of lives. More recently, the emphasis has been on increasing CPR
      capability through the development of prehospital emergency care systems and the involvement
      of the lay public in the provision of CPR. The effectiveness of this technique in the
      prehospital setting has been demonstrated in several community studies of patients in cardiac
      arrest where survival rates ranged from 11-17 percent.

      Additionally, for patients in ventricular fibrillation, the proportion of patients discharged
      alive ranged from 14-30 percent in five cities where the outcome of EMS programs has been
      examined. These successes, however, concealed many failures in which CPR could not reverse
      death even though correctly applied within established periods between arrest and
      resuscitation. However, considerable potential existed for improving CPR techniques and for
      making additional inroads towards the estimated 100,000 deaths each year in the United States
      that could be reversed through the widespread application of CPR.

      A major goal of CPR is to maintain adequate peripheral perfusion (particularly the cerebral
      and coronary circulation) during cardiac arrest while attempts are being made to restore
      normal cardiac function. Maneuvers which increase intrathoracic pressure, such as total
      airway occlusion during chest compression and abdominal compression by binding, have been
      shown to increase carotid blood flow in the dog.

      Sixteen periods of conventional CPR followed by SC-V CPR and return to conventional CPR were
      studied in 11 cases of in-hospital cardiac arrest at Johns Hopkins University. The findings
      indicated that simultaneous compression and ventilation at high airway pressures (SC-V CPR)
      greatly increased carotid flow velocity and radial artery pressure over values achieved with
      conventional CPR. Maximum benefit was achieved in patients in whom standard or conventional
      cardiopulmonary resuscitation was least effective. The increases in flow index noted with
      simultaneous compression and ventilation were up to 274 percent of control.

      The success of this new method of CPR had been demonstrated during in-hospital clinical
      trials. The benefits of this method suggested the need to test the technique in the
      prehospital setting where the vast majority of cardiac arrests occur.

      DESIGN NARRATIVE:

      Units of the Miami and Dade County Rescue Squads utilized the technique in a mid-point
      cross-over design. One of the three shifts at each of the study rescue stations had been
      thoroughly instructed in the SC-V CPR protocol. A second crew was given an intensive review
      of conventional CPR methodology. The third shift initially received the conventional CPR
      review and continued to perform conventional CPR. After six months, the third shift was
      trained in SC-V CPR and utilized the technique for one year. At the cross-over point, the
      crew trained in SC-V CPR received the same intensive review of conventional CPR as did the
      other crew. The conventional CPR crews, in turn, were trained in SC-V CPR. Total sample size
      was 994 patients, 494 in the treatment group and 500 in the control group.

      The study completion date listed in this record was obtained from the Query/View/Report (QVR)
      System.
    

Intervention name(s): cardiopulmonary resuscitation
Intervention type(s): Procedure
Intervention model: Crossover Assignment
Primary purpose: Treatment