title: Potassium induced cardiac standstill during conventional cardiopulmonary resuscitation in a pig model of prolonged ventricular fibrillation cardiac arrest: a feasibility study.
abstract: OBJECTIVE
  Potassium-based cardioplegia has been the gold standard for cardioprotection during cardiac surgery. We sought to evaluate the feasibility and the effects of potassium-induced cardiac standstill during conventional cardiopulmonary resuscitation (CPR) in a pig model of prolonged ventricular fibrillation (VF).
  
  
  METHODS
  VF was induced in 20 pigs, and circulatory arrest was maintained for 14 min. Animals were then resuscitated by standard CPR. Coincident with the start of CPR, 20 ml of saline (control group) or 0.9 mequiv.kg(-1) of potassium chloride diluted to 20 ml (potassium group) was administered into right atrium.
  
  
  RESULTS
  Administration of potassium resulted in asystole lasting for 1.0 min (0.2) in the potassium group animals. VF reappeared in all but one animal, in which wide QRS complex bradycardia followed. Restoration of spontaneous circulation (ROSC) was attained in two animals (20%) in the control group and in seven animals (70%) in the potassium group (p=0.070). Resuscitated animals in the potassium group required fewer countershocks (3, 4 vs. 2 (1-2)), smaller doses of adrenaline (1.84, 1.84 vs. 0.94 (0.90-1.00)mg), and shorter duration of CPR (8, 10 vs. 4.0 (4.0-4.0)min) than did the control group. Potassium concentrations normalised rapidly after ROSC in both groups, and the potassium concentrations at 5 min (5.5, 6.6 vs. 6.8 (6.5-7.8)mequiv.l(-1)) and 4h (4.9, 5.4 vs. 5.9 (5.1-6.4)mequiv.l(-1)) after ROSC were similar in the both groups.
  
  
  CONCLUSIONS
  In a pig model of untreated VF cardiac arrest for 14 min, resuscitation with potassium-induced cardiac standstill during conventional CPR was found to be feasible.
authors.affiliation: Department of Emergency Medicine, Chonnam National University Hospital, 42 Jebong-ro, Donggu, Gwangju, Republic of Korea. apostlelee@hanmail.net
authors.forename: Hyoung Youn
authors.initials: HY
authors.lastname: Lee
authors.forename: Byung Kook
authors.initials: BK
authors.lastname: Lee
authors.forename: Kyung Woon
authors.initials: KW
authors.lastname: Jeung
authors.forename: Sung Min
authors.initials: SM
authors.lastname: Lee
authors.forename: Yong Hun
authors.initials: YH
authors.lastname: Jung
authors.forename: Geo Sung
authors.initials: GS
authors.lastname: Lee
authors.forename: Tag
authors.initials: T
authors.lastname: Heo
authors.forename: Yong Il
authors.initials: YI
authors.lastname: Min
mesh_terms: D000818:Animals; D002314:Cardioplegic Solutions / Q000494:pharmacology*; D016887:Cardiopulmonary Resuscitation / Q000379:methods*; D004195:Disease Models, Animal; D005240:Feasibility Studies; D006323:Heart Arrest / Q000209:etiology / Q000503:physiopathology / Q000628:therapy*; D006324:Heart Arrest, Induced / Q000379:methods*; D006325:Heart Atria; D007267:Injections; D008297:Male; D011189:Potassium Chloride / Q000008:administration & dosage*; D013552:Swine; D013997:Time Factors; D014693:Ventricular Fibrillation / Q000150:complications / Q000503:physiopathology / Q000628:therapy*
chemical_list: D002314:Cardioplegic Solutions; D011189:Potassium Chloride