Expandable ECMO extension cannula system
An extension cannula for use with a conventional ECMO return cannula is provided. The extension cannula includes a flexible conduit transitionable between a collapsed insertion state and an expanded deployed state when in communication with blood flow from an ECMO machine via the ECMO return cannula. The extension cannula may be positioned through a conventional ECMO return cannula such that the proximal end of the flexible conduit is disposed within and proximal to the end of the ECMO return cannula, while the distal end of the flexible conduit is disposed in a patient's thoracic aorta to deliver oxygenated blood directly to the patient's thoracic aorta via one or more pores at the distal region of the flexible conduit to improve cerebral oxygenation, maintain systemic arterial pulsatility, and reduce the potential for end-organ injury.
1. A kit for use with an ECMO machine, the kit comprising:
a cannula comprising a proximal region having an inlet configured to be coupled to the ECMO machine, and an outlet configured to be disposed at a location within a patient's vasculature proximal of a patient's renal vessels;
an extension cannula comprising:
a flexible conduit having a proximal end, a distal end, a length extending therebetween, and a lumen in an expanded deployed state, the flexible conduit configured to transition from a collapsed insertion state to the expanded deployed state when in communication with a blood flow from the ECMO machine so that the lumen forms a continuation of a blood flow path through the cannula; and
an elongated shaft having a distal region coupled to the distal end of the flexible conduit, the elongated shaft configured to advance the flexible conduit in the collapsed insertion state to locate the distal end beyond the patient's renal vessels; and
a peel-away introducer disposed on at least a portion of the flexible conduit, the peel-away introducer configured to be retracted proximally relative to the flexible conduit and peeled off of the flexible conduit,
wherein the length of the flexible conduit is selected so that when the proximal end is located within the outlet at the location within the patient's vasculature proximal of the patient's renal vessels, the distal end extends beyond the patient's renal vessels, and
wherein the elongated shaft is configured so that the blood flow path does not pass through the elongated shaft.
2. The kit of claim 1 , wherein the peel-away introducer comprises a diameter that is at most equal to a diameter of the cannula.
3. The kit of claim 1 , wherein the peel-away introducer is configured to extend along an entire length of the flexible conduit.
4. The kit of claim 1 , wherein the elongated shaft extends from the distal end of the flexible conduit proximally along a lateral side of the flexible conduit.
5. The kit of claim 1 , wherein the elongated shaft extends from the distal end of the flexible conduit proximally within the lumen along a longitudinal axis of the flexible conduit.
6. The kit of claim 5 , wherein the elongated shaft extends along a center portion of the lumen.
7. The kit of claim 1 , wherein the elongated shaft comprises a hypotube having a lumen configured to receive a guidewire therethrough.
8. The kit of claim 1 , wherein the extension cannula further comprises a support coupled to a distal region of the flexible conduit, the support extending circumferentially along the flexible conduit and configured to transition from a collapsed delivery state to an expanded deployed state.
9. The kit of claim 8 , wherein the extension cannula further comprises a plurality of connection structures extending between the distal end of the flexible conduit and the support, the plurality of connection structures configured to transition from a collapsed delivery state to an expanded deployed state.
10. The kit of claim 9 , wherein a distal end of the elongated shaft comprises an atraumatic tip configured to be coupled to the support via the plurality of connection structures.
11. The kit of claim 1 , wherein the flexible conduit comprises at least one of polyethylene, polyurethane, or nylon.
12. The kit of claim 1 , wherein an outlet of the flexible conduit comprises one or more pores disposed at a distal region of the flexible conduit.
13. The kit of claim 1 , wherein the proximal end of the flexible conduit is configured to be fixedly coupled to the cannula within the outlet of the cannula.
14. The kit of claim 1 , further comprising one or more sensors disposed at a distal region of the extension cannula, the one or more sensors configured to measure at least one of pressure, flow, or oxygen saturation within the patient's vasculature.
15. The kit of claim 14 , further comprising:
a console operatively coupled to the one or more sensors, the console configured to display measurements of the one or more sensors,
wherein the elongated shaft comprises a lumen sized and shaped to receive one or more electrical wires extending between the one or more sensors and the console.
16. A method for improving systemic perfusion, the method comprising:
advancing a distal end of a flexible extension cannula within a patient's vasculature via an elongated shaft coupled to the distal end of the flexible extension cannula, a proximal region of the flexible extension cannula coupled to an outlet of an ECMO return cannula in fluid communication with an ECMO machine, at least a portion of the flexible extension cannula disposed within a peel-away introducer;
positioning the peel-away introducer into the patient's vasculature, such that a proximal end of the peel-away introducer remains external to the patient and the distal end of the flexible extension cannula is positioned within the patient's vasculature;
retracting the peel-away introducer relative to the flexible extension cannula and peeling the peel-away introducer off of the flexible extension cannula;
advancing the ECMO return cannula into the patient's vasculature such that the flexible extension cannula extends from a location proximal to the patient's renal vessels to a location beyond the patient's renal vessels;
transitioning the flexible extension cannula from a collapsed insertion state to an expanded deployed state when in communication with a blood flow from the ECMO machine, the flexible extension cannula comprising a lumen in the expanded state; and
delivering the blood flow through the lumen of the flexible extension cannula to the location beyond the patient's renal vessels via a plurality of pores disposed at a distal region of the flexible extension cannula to thereby improve systemic perfusion,
wherein the elongated shaft is configured so that the blood flow path does not pass through the elongated shaft.
17. The method of claim 16 , wherein transitioning the flexible extension cannula from the collapsed insertion state to the expanded deployed state comprises transitioning a support extending circumferentially along a distal region of the flexible extension cannula from a collapsed delivery state to an expanded deployed state.
18. The method of claim 17 , wherein transitioning the flexible extension cannula from the collapsed insertion state to the expanded deployed state comprises transitioning a plurality of connection structures extending from the distal end of the flexible extension cannula to the support from a collapsed delivery state to an expanded deployed state.