Mechanisms and alternative methods of achieving cardiac arrest.
Elective cardiac arrest during surgery can be achieved by inducing depolarization, polarization, or influencing calcium mechanisms. Depolarized arrest, induced by elevating the extracellular potassium concentration, is currently the most commonly used technique. However, injury associated with ionic imbalance involving sodium and calcium overload, together with maintained metabolic processes aimed at correcting these imbalances, have lead to alternatives being sought. "Polarized" arrest, induced by sodium-channel blockers or by agents that activate potassium channels, has been shown to exert equal or superior protection. Similarly, agents that induce calcium desensitization may also prove to enhance protection. These alternative techniques, however, require extensive characterization before introduction into routine clinical use can be recommended.
Chambers
David J
DJ
Cardiac Surgical Research/Cardiothoracic Surgery, The Rayne Institute, Guy's and St Thomas' NHS Hospital Trust, St Thomas' Campus, London SE1 7EH, United Kingdom. david.chambers@kcl.ac.uk
D000241:Adenosine / Q000494:pharmacology; D000818:Animals; D002121:Calcium Channel Blockers / Q000494:pharmacology; D006348:Cardiac Surgical Procedures; D002314:Cardioplegic Solutions / Q000494:pharmacology; D006324:Heart Arrest, Induced / Q000379:methods; D006329:Heart Conduction System / Q000187:drug effects*; D006801:Humans; D006996:Hypocalcemia / Q000503:physiopathology; D015221:Potassium Channels / Q000187:drug effects; D011412:Propanolamines / Q000494:pharmacology; D015222:Sodium Channels / Q000187:drug effects
D002121:Calcium Channel Blockers; D002314:Cardioplegic Solutions; D015221:Potassium Channels; D011412:Propanolamines; D015222:Sodium Channels; D000241:Adenosine; C036604:esmolol