Case scenario V AV ECMO Dr Pranay Oza
Case Summary 53 y/m, k/c/o MVP with myxomatous mitral valve with severe Mitral regurgitation underwent Mitral valve replacement with mini thoracotomy Pump time nearly 3½ hours, came off pump well Had desaturation on ventilator in ICU immediately on arrival requiring 100% FiO2 Unable to recruit lungs due to hypovolemia & hypotension. Fluid responsive hypotension so fluid of around 2.5 l was given in 6 hrs. Developed severe hypoxia with hypotension & near cardiac arrest
Case Summary Resuscitated & was put on femoro-femoral cardiopulmonary bypass Echo immediately after resuscitation showed poor LV but on pump with flow of around 2.3l/min LV function improved Patient had persistent pulmonary oedema Hemodynamically stabilize with partial CPB & on dobutamine & adrenaline support Decided to switch over to ECMO from CPB & call was given to ECMO team
On arrival On pump with flow of 2.3L/min MAP of 54 mm hg Inotropic score 14 PO2 44 SPO2 86% SVO2 45% Serum Lactates 92mg/dl Under sedation, pupils BERL
Peripheral cannulation VA with right femoral artery (Edward cannula 18F), right femoral vein (edward cannula 22F) & distal perfusion cannula 14 F Open technic cannulation
X ray post op X ray post arrest
Problems Contused rt lung probably due to rt mini thoracotomy Worsening lungs even involvement of left lung, Pulmonary oedema early ARDS kind of picture or Pump Lung Severe LV dysfunction may be due to Poorly preserved myocardium Prolonged hypoxia Oliguria with ARF (creat ~ 2.5)
Plan Needs cardiac as well as respiratory support To continue initially with VA ECMO but then once cardiac stability is achieved switch to V-AV & finally VV Venous cannula size is small (can support for only 3L/min of flow)might require to put an additional cannula for drain, if drainage becomes an issue Change distal perfusion cannula as it is non functional Changed from roller & regular hollow fiber oxygenator to centrifugal pump with PMP oxygenator Maintain haematocrit > 30
Modus operandi Accept same cannula as already on femorofemoral pump To stop roller pump & put centrifugal pump (revolution, Sorin) & PMP Oxygenator (Hilite 7000 lt, Medos) in the circuit & start on VA ECMO Change distal perfusion cannula as it was probably got blocked to 7 F Introducer sheath
Initiation Started with flow of 3 l/min of flow with 1:1 sweep gas Initial hypotension but then stabilize with flow of 3.5l/min Packed cell transfusion 3 units
Hypotension Sudden hypotension with tube chattering, with respiratory variation on arterial tracing with pulse pressure of ~ 5 Hypovolaemic? Cause Bleeding from femoral sites, generalized oozing ACT ~ 300, INR ~ 3.5, PTT > 120 sec, platelet 112000 FFP transfusion (6) given with packed cell (2) transfusion
Parameters post ECMO MAP 82 mm Hg Pulse pressure ~ 17 mm Hg SPO2 100% SVO2 65 Lactate 52 Inotropic score 11
Parameters ventilator settings Rest ventilator settings PCV mode Rate 12 Peak Inspiratory 30 PEEP 14 FiO2 40% Further reduced to Peak pressure 22 PEEP 12 FiO2 30%
Parameters 08 02 2014 MAP 90 Pulse pressure 17 PO2 90 SPO2 100 SVO2 65 Lactate 56 Inotropic support 11 09 02 2014 MAP 85 Pulse pressure 24 PO2 65 SPO2 96 SVO2 72 Lactate 19 Inotropic support 4
Parameters Pre V AV ECMO Post V AV ECMO
Interpretation of arterial blood gas in VA ECMO Not of much value in full ECMO support Tells you roughly about the native & ECMO circulation If PO2 in VA ECMO is more (> 200), suggestive of Very low native circulation & high ECMO circulation
Interpretation of arterial blood gas in If PO2 in VA ECMO is low, suggestive of Native circulation is > ECMO circulation, either due to - North south syndrome VA ECMO Reduced ECMO flow due to decreased preload, increased afterload or technical issues Improving cardiac contraction
Plan 2 Switched to V AV on 9 02 2014 at 12.10 pm Arterial flow 2.5, venous flow 3l/min, sweep gas 5l/min Always keep venous line partially occluded as by preferrence most of the flow will go to it due to low resistance Arterial Venous partially clamped
Post V-AV after one hour MAP 72 Pulse pressure 20 PO2 102 SPO2 100 SVO2 68 Lactate 19 Inotropic support 4
Post V-AV after one hour ABG post V AV PO2 104.7 PCO2 32 PH 7.497 HCO3 24 Next plan to slowly come down on arterial flow monitoring MAP, pulse pressure & 2 D echo.
VA weaning flow 800 ml/min MAP 98, 142/80 Pulse 128 SPO2 97% SVO2 50.8% Lactate 13.2 2 D echo N, aortic velocity 1.5, Mitral valve gradient (peak) ~ 9 Inotropic score 0
Trial off 4 hrs MAP 91, 145/75 Pulse 124 SPO2 99 SVO2 71.4 Lactate 12.6 2 D echo N, aortic velocity 1.4, Mitral val gradient 9 (peak) Inotropic score 0
Decannulation ABG PH 7.456 PO2 78.1 PCO2 28.7 HCO3 24.3 Decannulation done around 10 am on 12/2/14 & switched over to VV ECMO with flow of 4l/min Remained stable after arterial decannulation, hemodynamics & saturation maintained. Plan to repeat 2 D echo & lactate, ABG after 12 hrs If SPO2 > 95% then to start weaning from VV ECMO by decreasing FiO2 from ECMO
Post Decannulation on VV ECMO
Post Decannulation on VV ECMO MAP 78, 121/60 Pulse 148 SPO2 99 ABG PH 7.568 PO2 75.9 PCO2 27.3 HCO3 24.3