1) Intra aortic Balloon Pump (IABP)
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Mechanism
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Polyethylene balloon filled with helium (low viscosity/diffusion).
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Inflates in diastole → augments diastolic BP/coronary perfusion.
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Deflates in systole → mild afterload reduction, ↓ workload/O₂ consumption.
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Support: ~0.5–1 L/min.
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Triggering & Settings
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Triggers: ECG, pressure, pacing, or spontaneous.
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Frequencies: 1:1 → 1:2 → 1:3 (wean often unnecessary in shock).
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Augmented BP is not used to titrate vasoactives; use MAP.
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Placement & Alarms
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Commonly femoral; also axillary/brachial; confirm by CXR.
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Alarms: low helium, gas leak, no trigger (switch ECG↔pressure).
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Migration more common axillary; may need adjustment.
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Rupture (Emergency)
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Turn off, remove promptly (clotting risk), raise BP, 100% FiO₂/non-rebreather or ventilator, Trendelenburg.
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Trials/Outcomes
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IABP-SHOCK II (AMI shock): no outcome difference vs standard care.
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Alt-SHOCK II (decomp HF): futility, notable bleeding/vascular/limb ischemia.
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Guideline note (US): against routine use in AMI shock (context from talk).
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2) Impella (example: CP)
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Mechanism
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Pigtail catheter pump in LV: unloads LV, ↓ LVEDP/volume, ↓ work/O₂ use.
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Pumps to ascending aorta: ↑ MAP, forward flow, coronary perfusion.
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Typical support ~3.5 L/min (CP); larger surgical version higher.
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Access & Positioning
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14F sheath (femoral/axillary); peel-away + repositioning sheath.
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Confirm with echo (parasternal long) and console waveforms (LV & aortic).
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Complications/Management
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Thrombus/heat if inadequate anticoagulation; device off → emergency removal/replacement.
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Migration: adjust via locking hub under echo.
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Vascular issues higher than IABP; mitigate tension/stitching.
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Evidence
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DANGER-Shock (STEMI shock, non-comatose): mortality reduction; higher complications; expertise required.
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3) VA-ECMO (brief)
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Pros: Strong peripheral perfusion, oxygenation, transportable cannulation.
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Cons: Stroke/bleeding/vascular risks; ↑ afterload (ensure aortic valve opens; risk aortic thrombus).
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Trial Mentioned: ECLS-Shock (AMI shock, high lactate/very sick): no outcome difference vs standard care.
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Variant: LAVA-ECMO (LA drainage via septostomy) for indirect LV unloading.
4) Systems, Complications, Troubleshooting
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Complications common: bleeding, limb ischemia, device migration, suction/chugging.
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Mitigation: micropuncture, ultrasound/fluoro/angiography, anticoagulation, echo, invasive hemodynamics.
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Shock Team & Workflow
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Early recognition, early support, invasive hemodynamics, hub-and-spoke transfers, wean/escalate by protocol.
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Multidisciplinary ICU collaboration essential.
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5) Practical Pearls
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Titrate vasoactive drugs to MAP, not augmented BP.
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For hypotension/suction alarms: check position, volume, bleeding, RV failure, acidosis.
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When uncertain: re-review indication, imaging, hemodynamics, call for help.