{"id":5241,"date":"2011-07-14T20:24:41","date_gmt":"2011-07-14T20:24:41","guid":{"rendered":"http:\/\/crashtext.org\/misc\/extracorporeal-membrane-oxygenation-and-bypass.htm\/"},"modified":"2014-09-17T13:41:02","modified_gmt":"2014-09-17T17:41:02","slug":"ecmo","status":"publish","type":"post","link":"https:\/\/crashingpatient.com\/intensive-care\/ecmo.htm\/","title":{"rendered":"Extracorporeal Corporeal Life Support – ECMO"},"content":{"rendered":"
best review thus far with excellent pictures<\/a> Review from the NEJM (NEJM 2011;365(20):1905) If you bypass lung entirely, it has no way to get CO2 becomes alkalotic and may infarct If V\/A then heart must pump against the pressure gradient introduced into the aorta You know when there is no native CO because there will be a straight arterial pressure tracing just showing a mean pressure Pulmonary pressure from a hyperdynamic right heart will overcome hypoxic vasoconstriction Oxygen is flow dependant Muscle\/kidney\/Liver clear lactate ECMO works by sending blood through artificial lung either membrane or hollow fiber. Blood flows counter-current to gas Rated flow of a membrane is how much blood can be raised from 75% to 95% O2 sat in a given time Maintain Activated clotting time of 180-200 Study of crash bypass for cpr-nonresponsive cardiac arrest (Inten Care Med 2007;33:758) CESAR trial shows cost effectiveness for transfer to ECMO center if severe resp fx (Lancet 2009; <\/a><\/a> venovenous bypass review<\/a> When you put a person on cardiopulmonary bypass despite being on full > cardiopulmonary bypass defined as diversion of all systemic venous > return to the oxygenator, there is sufficient amount of noncoronary > collateral and other flow to the heart which will fill the heart (for > eg bronchial flow etc). This will normally be ejected by the heart and > the left ventricle will be kept empty. Now if the heart is asystolic > or fibrillating it cannot kick out this volume into the aorta and so > the heart will now distend and as per Laplaces law with increasing > radius there will be increasing wall tesnions (to put it in simplistic > terms it becomes increasingly difficult to distend a baloon as it > enlarges and the wall tension will be higher) . This implies that > wall tesnion wll increase and with increasing distention the wall > tension will increase and thus decrease progressive subendocardial > perfusion and at one stage there will be no subendocardial myocardial > perfusion , a condition which is practically worse while not > externally visible. This distention is negated by ‘venting” ie a > placing another cannula or catheter to collect this excessive return > and divertting it away from the left ventricle , be it by direct > incision on the ventricle (less often used today ) or by indirect > methods ranging from the aorta to the pulmonary artery (based on the > fact that it is a valveless circuit after the pulmonary valve).(I can > go on further (as this is a very important topic in CPB > pathophysiology) but to make a long story <\/p>\n short – you need to have the > heart empty and beating for it to function well. If it cannot beat > prevent it from distending by approproate venting. At times we > actually have to squeeze the heart and empty it and prevent > distention. A term which is we refer to as “Theri haath me Jagannath” > meaning (roughly translated that “the Lord is in your Hands” to > emphasize that the lfie of the patient depends on you preventing > distention (and actually is a vulgar joke (( you could get it \ud83d\ude09 )) > Prasanna | | |<\/p>\n","protected":false},"excerpt":{"rendered":" Array<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_genesis_hide_title":false,"_genesis_hide_breadcrumbs":false,"_genesis_hide_singular_image":false,"_genesis_hide_footer_widgets":false,"_genesis_custom_body_class":"","_genesis_custom_post_class":"","_genesis_layout":"","footnotes":""},"categories":[18],"tags":[],"yoast_head":"\n
<\/p>\nExtra-corporeal Membrane Oxygenation (ECMO)<\/h2>\n