Chapter question: Which vessels, which cannulae, which route — and what must be done at the moment of cannulation to prevent the complications the rest of Part III is about?
Evidence search date: 6 September 2026. Sources: ELSO Red Book 6th edition Ch 4 (surgical cannulation); Taha, ECMO: A Practical Guide to Management Ch 7; ISCCM Manual Ch 25 and Ch 30; and a Journal of Thoracic Disease review (2015). No randomised evidence exists for any decision in this chapter — all of it is expert practice and observational.
What this chapter covers — and what it does not
This chapter owns | Deferred to |
Choosing the configuration; arterial vessel assessment and cannula sizing; femoro-femoral, axillary/subclavian, carotid and central cannulation; percutaneous versus surgical versus graft techniques; the distal perfusion cannula as a cannulation-time decision; position confirmation; triple cannulation as an upgrade | Who to cannulate → Chapter 11
VV cannulation and the vessel-sizing principle → Chapter 5
Afterload, mixing point and haemodynamics → Chapter 13
LV distension and unloading → Chapter 15
Differential hypoxaemia → Chapter 16
Established limb ischaemia — monitoring and management → Chapter 17
Weaning and decannulation → Chapter 18
Cannulation during arrest → Chapters 19–20 |
12.1 The decision that VV cannulation does not have to make
Chapter 5 covered cannulation for VV support, where every cannula sits in a vein. VA cannulation adds an artery, and with it a set of consequences that have no VV equivalent:
- Blood is returned against the direction of native flow, creating a mixing point (Chapter 13) and the possibility of differential hypoxaemia (Chapter 16).
- The return cannula occupies an artery that a limb depends on, which is why limb ischaemia is a VA-specific complication (Chapter 17).
- Retrograde flow raises left ventricular afterload, which is why LV distension is a VA-specific problem (Chapter 15).
Physiology — the choice of arterial site is a choice about where the mixing point sits
Femoral return sends oxygenated blood up the descending aorta, so it meets native output somewhere in the aorta — typically between the ascending aorta and the renal arteries, though the exact position depends on the balance between LV output and ECMO flow. Everything proximal to that watershed is perfused by the patient's own — potentially deoxygenated — blood, including the coronary and cerebral arteries.
Axillary, subclavian and central return deliver blood antegrade, from the arch downwards. There is no watershed to worry about, and afterload is lower.
So the arterial site is not just a question of access. It determines whether differential hypoxaemia is possible at all, and it is the single most consequential technical decision in VA ECMO.
Sources: ISCCM Manual Ch 25; Taha Ch 7.
12.2 Choosing the configuration
Configuration | Advantages | Disadvantages | Use when |
Femoro-femoral
Femoral vein drainage, femoral artery return | Fastest; least invasive; percutaneous; can be done anywhere, including during arrest | Retrograde flow — differential hypoxaemia, raised LV afterload and distension, aortic root thrombus; lower-limb ischaemia; immobilises the patient | The default in emergency and cardiogenic shock, and the only realistic option during arrest |
Femoral vein to axillary or subclavian artery
(usually via an end-to-side graft) | Antegrade flow — no watershed, reduced LV afterload, similar in effect to central. With right internal jugular drainage instead, becomes an upper-body configuration that frees the legs for rehabilitation | Surgical, needs an operating room, cannot be done during arrest; risk of upper-limb hyperperfusion, swelling and compartment syndrome requiring fasciotomy; higher risk of injury to arm vessels and nerves | Anticipated long runs; bridge to transplant or durable device; where mobilisation matters; where femoral vessels are unusable |
Central
Right atrium drainage, ascending aorta return | Excellent venous drainage and fully antegrade delivery, offsetting the watershed phenomenon entirely; LV can be vented directly through the apex or pulmonary veins, so distension is not a problem | Major bleeding and infection risk; requires a cardiac surgical team; difficult to institute in an emergency; chest left open or cannulae tunnelled | Post-cardiotomy shock — already on bypass cannulae — or when peripheral cannulation cannot deliver adequate perfusion or oxygenation |
Right common carotid artery return | An option when femoral vessels are unusable | Associated with a reported 5–10% risk of large watershed cerebral infarction | Rarely, in adults. See the caution below |
Composite of Taha Ch 7, ISCCM Manual Ch 25 and Ch 30, and the J Thorac Dis review.
Pitfall — two sources agreeing is not two sources
The 5–10% watershed cerebral infarction figure for carotid cannulation appears in the ISCCM Manual and in the J Thorac Dis review in near-identical wording. That is a strong sign of a shared upstream source rather than independent confirmation.
The figure is reproduced here because it is the only quantification available and it is directionally important — carotid return carries a substantial stroke risk. But it should be treated as one claim seen twice, not as a corroborated estimate, and the primary source has not been retrieved. This trap recurs throughout the ECMO literature, where a small number of reviews are copied widely.
12.3 Sizing the arterial cannula
Chapter 5 established the vessel-sizing principle for veins. The same arithmetic applies to the artery, but the consequences of getting it wrong differ completely: an oversized venous cannula obstructs drainage, whereas an oversized arterial cannula occludes the limb.
The method described by Taha and colleagues:
Step 1 — assess the vessel with ultrasound. Compressibility and colour Doppler confirm patency; measure the lumen diameter. If the contour is distorted by adjacent tissue, use the circumference in millimetres instead.
Step 2 — calculate the vessel size in French:
Step 3 — choose a cannula smaller than the calculated vessel size, by at least 1–3 Fr (1 Fr for paediatric, up to 3 Fr for adult patients).
Danger — the arterial cannula must not fill the artery
Taha and colleagues state the requirement plainly: assessing arterial size by ultrasound before choosing the cannula is mandatory, because "a bigger cannula most likely will take the whole artery diameter causing distal limb ischemia."
This is the difference between Chapter 5's framing and this one. In VV, the sizing formula gives a ceiling you may approach for the sake of flow. In the femoral artery, approaching that ceiling is precisely what produces the complication — the cannula must leave lumen for the limb, or a distal perfusion cannula must carry it (§12.5).
The corollary: the arterial cannula is chosen for the vessel, not for the target flow. If the artery cannot accept a cannula large enough to deliver the flow you want, that is an argument for a different arterial site or a graft — not for a bigger cannula.
Clinical pearl — published cannula sizes, for orientation only
- Femoral artery return: an arterial cannula 23 cm long is preferred in femoro-femoral configuration, to reach the iliac bifurcation.
- Axillary or subclavian via graft: an 8 mm graft sutured end to side, with a 21–24 Fr cannula tunnelled from a separate incision into the graft.
- Central: 22–24 Fr for aortic cannulation; a two-stage venous cannula of 32–34 up to 40–46 Fr. Sizes are defined by body surface area and the flow calculated to meet metabolic requirements.
- Small or unusually narrow vessels: percutaneous placement is described as hazardous; a 6–8 mm Dacron graft sutured to the vessel is preferred.
These are the figures the sources give. They orient rather than prescribe — the vessel measurement in front of you governs.
12.4 Technique by route
12.4.1 Percutaneous femoral artery
- Assess with ultrasound first — patency, diameter, and the level of the common femoral bifurcation into superficial and profunda branches.
- A single arterial puncture is preferred. Use the longitudinal (in-plane) ultrasound view, which shows the needle track and helps avoid transfixing the artery — a posterior-wall puncture in a patient about to be fully anticoagulated is a retroperitoneal haemorrhage waiting to happen.
- If the puncture fails, or the guidewire catches and there is no alternative access site, surgical exploration of the access vessels is warranted. Repeated blind attempts on an artery that is about to carry a large cannula is the wrong response.
12.4.2 Surgical cutdown to the femoral vessels
The ELSO Red Book describes the approach, which is worth knowing even for physicians who will not perform it:
- Position supine, with a roll under the buttock if time allows, and the feet moved to the edge of the bed to open the femoral triangle.
- Locate the artery by palpation, ultrasound, or the midpoint of the inguinal ligament between the anterior superior iliac spine and the pubic tubercle.
- Incision: a vertical incision is quick and lets the inguinal ligament be identified as a fixed anatomical landmark, but makes tunnelling through the skin flap harder. An oblique skin-crease incision gives better flaps but poorer distal exposure. A hockey-stick extension down the course of the saphenous vein solves this and is the preferred approach.
- Deepen through superficial fascia to the deep fascia — the saphenous vein lies in this layer; if found, follow it to the saphenofemoral junction. Divide the deep fascia in line with the vessels, ligating circumflex branches as needed, and dissect until the common femoral bifurcation is identified.
Clinical pearl — you may only need to cut down on the artery
The Red Book makes a point that is easy to miss and operationally useful: it may be necessary to insert only the arterial cannula surgically — because venous cannulae are already in situ in a patient being converted from VV, or because a decision was made to place the venous cannula percutaneously at a different site.
"This approach has great merit because it allows less extensive dissection and preserves the vein more effectively." Mixing routes is not a compromise; in the right patient it is the better operation.
Femoral vessels are described as usable from 15–20 kg upwards.
12.4.3 Axillary or subclavian artery
The distal right subclavian artery is exposed through a 3–4 cm subclavicular incision, distal to the branching of the thyrocervical trunk. The artery is slung proximally and distally, an 8 mm graft is sutured end to side, and a 21–24 Fr cannula is tunnelled from a separate incision, inserted into the graft and advanced to the arteriotomy. The axillary artery is cannulated by the same method.
Danger — the upper limb can be over-perfused, not under-perfused
This is the failure mode that catches people who have only managed femoral cannulation. Direct arterial cannulation of the axillary or subclavian artery — or a graft that directs too much flow distally — causes distal limb hyperaemia, which can progress to compartment syndrome requiring fasciotomy, with significant swelling and venous inadequacy.
So the limb complication of upper-body cannulation is the mirror image of the femoral one. Both limbs need examining, and the question is different at each end of the patient: ischaemia below, hyperperfusion above.
Sources: ISCCM Manual Ch 25; Taha Ch 7.
12.4.4 Central cannulation
Right atrium and ascending aorta under direct surgical exposure, via sternotomy or right anterior thoracotomy. The chest may be left open with a sterile dressing, or the cannulae tunnelled through soft tissue and skin and the chest closed.
Its advantages follow directly from the physiology in §12.1 — very good venous drainage, fully antegrade delivery offsetting the watershed phenomenon, and LV distension is not a problem because the LV can be vented through the apex or the pulmonary veins. Its disadvantages are the ones surgery always brings: bleeding, infection, the need for a cardiac surgical team, and difficulty instituting it in an emergency.
12.5 The distal perfusion cannula — a decision made at cannulation, not afterwards
This is the most important operational content in the chapter, because the window in which it is easy closes within minutes.
Danger — place the distal wire BEFORE the arterial cannula
Taha and colleagues give the reason directly: "It is favorable to place a wire distally prior to placement of the actual arterial cannula, since distal flow is usually considerably lower after placement of the arterial cannula."
Once the arterial cannula is in, the artery below it is barely perfused. The pulse you were going to use to find the superficial femoral artery is gone, the vessel is smaller, and what was a straightforward antegrade puncture becomes difficult in a fully anticoagulated patient with a critical limb.
Decide about distal perfusion before you cannulate, and put the wire in first. In genuine emergencies and in ECPR this can be done afterwards — but that is a concession to circumstance, not the technique.
How it is done. Locate the common femoral bifurcation by ultrasound. Access the superficial femoral artery antegrade, just past the bifurcation. Confirm the wire passes freely down the leg before committing.
What to use. A 6–9 Fr vascular reinforced sheath is recommended in preference to a standard access cannula, because it resists kinking. The ISCCM manual describes an antegrade 5 Fr cannula placed in the femoral artery before the supply cannula and connected to the supply circuit.
Alternatives when antegrade access is not possible:
- Retrograde posterior tibial artery cannulation — the ELSO Red Book includes a surgical technique for this specifically.
- A surgical end-to-side graft from the ECMO circuit into the superficial femoral artery.
- A chimney graft (Dacron T-graft).
Pitfall — the retrograde flow steals from the limb twice
Femoral arterial cannulation threatens the limb by two mechanisms, not one. The obvious mechanism is mechanical: the cannula partly or completely occludes the vessel. The second is easily forgotten — the retrograde flow in the aorta also drives what little native flow remains in that leg backwards, so the limb loses its residual antegrade supply as well.
This is why a palpable pulse before cannulation is not reassurance afterwards, and why monitoring cannot rely on pulses in a patient who is on vasopressors with non-pulsatile flow. Chapter 17 covers monitoring and management; the point here is that the decision to protect the limb belongs to the cannulation, not to the ward round.
12.6 Confirming position, and what to do before leaving the bedside
- Echocardiography and chest radiograph to confirm cannula positions and screen for complications.
- Site a right upper-limb arterial line — right radial for preference. The ISCCM manual states the reason: because the watershed sits between LV output and retrograde ECMO flow, the right upper limb samples the blood reaching the coronary and cerebral circulations. A left radial or femoral arterial line can read reassuringly while the brain is hypoxaemic. This is monitoring that must be established at cannulation (Chapter 16).
- Examine and document both lower limbs and the cannulated upper limb, and record whether a distal perfusion cannula was placed — and if not, why not, and what the plan is.
- Record the cannula sizes, insertion depths and skin markings.
Clinical pearl — cannulate in a controlled environment whenever the patient allows it
The ISCCM manual notes that sterile technique and controlled implantation — in an operating room or catheterisation suite — yield greater success than emergent application, and that infection risk rises with duration of support.
Emergency femoral cannulation at the bedside is often unavoidable and is the right call when it is. But where there is a choice, the setting is part of the technique.
12.7 Triple cannulation as an upgrade
Configuration is not fixed at cannulation. The ISCCM manual frames the principle well: the patient's physiology and requirements keep changing, whichever mode was instituted, and triple cannulation exists to answer problems that emerge later.
Upgrade | Problem it solves |
VVA — an additional venous drainage cannula added to VA | Insufficient venous drainage from a small cannula or a very large patient, causing reduced flows or differential hypoxaemia. Also used to improve drainage in order to unload the left ventricle (Chapter 15) |
VAV — an additional venous return limb added to VA | Coexistent severe lung and heart failure — oxygenated blood is delivered to both the right atrium and the artery |
Danger — the added cannula goes in under live imaging
The ISCCM manual is explicit that when upgrading VA ECMO, the additional venous cannula should always be inserted under live imaging. The two limbs are then merged with a Y-connector.
Chapter 9's warning applies with force here: adding a second drainage limb creates differential flows across two cannulae and turbulence at the Y-connector, which Taha identifies as a route to circuit thrombosis. A second cannula placed in the wrong position can also reduce effective flow by increasing recirculation. This is an upgrade with real costs, not a free improvement.
12.8 Controversies
Controversy 1 — Should a distal perfusion cannula be placed routinely, or selectively?
The question. Should every femoral arterial cannulation include a distal perfusion cannula at the time of insertion, or should it be reserved for patients who show signs of limb compromise?
The case for routine placement. It is far easier before the arterial cannula is in than after — distal flow, and therefore the target vessel, is much reduced afterwards. Limb ischaemia in this population is common, hard to detect (non-pulsatile flow, vasopressors, sedation), and its consequences run to compartment syndrome, muscle necrosis and amputation. A 6–9 Fr sheath is a small addition to a procedure that is already placing a large arterial cannula.
The case for selective placement. It is an additional arterial puncture in a patient who will be fully anticoagulated, with its own bleeding, dissection and infection risk. Not every patient develops ischaemia — the cannula-to-vessel ratio (§12.3) is the primary determinant, and a well-sized cannula in a large artery may not need it. It adds time to a procedure that is sometimes being done during resuscitation.
What the evidence actually shows. The sources consulted describe distal perfusion as recommended and note that reperfusion catheters increase the likelihood of limb preservation, but none reports a randomised or controlled comparison of routine versus selective placement, and no threshold cannula-to-vessel ratio is given at which it becomes necessary. Certainty: very low.
Where practice actually sits. Many high-volume centres place one routinely with femoral arterial cannulation, on the reasoning that the cost of placing it unnecessarily is small and the cost of needing it later is high. Others size the cannula conservatively and monitor closely.
What would resolve it. A randomised comparison with limb outcomes, or at minimum a cohort study relating cannula-to-vessel ratio to ischaemia so that a threshold for selective placement could be defined. Neither is available here.
This book's position. Decide before cannulating and, if in doubt, place the wire first — the asymmetry of difficulty is the governing fact. A wire placed and not used costs little; a wire needed and not placed is a difficult procedure on a threatened limb.
Controversy 2 — Femoral or upper-body arterial return for the patient who will need weeks of support?
The question. Femoral return is fast and can be done anywhere. Axillary or subclavian return is antegrade, avoids the watershed, lowers afterload and frees the legs. When support is likely to be prolonged, should the arterial cannula be moved — or sited there from the outset?
The case for femoral. Speed, percutaneous access, no operating room, feasible during arrest. In the patient whose trajectory is unknown — which is most of them at hour zero — it is the only responsible first choice.
The case for upper body. It removes the mechanism of differential hypoxaemia entirely rather than monitoring for it; it reduces LV afterload rather than treating the distension it causes; and combined with right internal jugular drainage it produces a configuration in which the patient can be mobilised, which matters greatly for anyone being bridged to transplant or a durable device.
What the evidence actually shows. The advantages and disadvantages above are consistently described across the sources, but no comparative outcome data are offered for femoral versus axillary return, and the harms differ in kind rather than in magnitude — limb ischaemia below versus hyperperfusion and compartment syndrome above. Certainty: very low.
Where practice actually sits. Femoral first in the emergency; conversion to upper-body or central considered when the run is clearly going to be long, when differential hypoxaemia is a live problem, or when mobilisation becomes a goal. The decision is usually made in the first week rather than at cannulation.
What would resolve it. A registry analysis relating arterial site to limb complications, differential hypoxaemia, mobilisation and neurological outcome, adjusted for the confounding by indication that makes the observational literature hard to read.
The transferable point. The trade-off is not "safer versus riskier". It is which complication you would rather have, and how much the ability to mobilise is worth to this particular patient's destination (Chapter 11 §11.6).
12.9 The errors that recur
Error | Correction |
Choosing the arterial cannula for the target flow | Choose it for the vessel. If the artery cannot take a cannula big enough, change site or use a graft — do not upsize |
Deciding about distal perfusion after the arterial cannula is in | Distal flow is much lower by then. Place the wire first |
Siting the arterial line in the left arm or femoral artery | Right radial samples what the brain and heart receive. Left-sided lines can read reassuringly during differential hypoxaemia |
Repeated percutaneous attempts on a difficult artery | Failed puncture or a caught wire with no alternative site is an indication for surgical exploration |
Examining only the cannulated leg | Upper-body cannulation causes hyperperfusion and compartment syndrome. Different question at each end of the patient |
Assuming a palpable pre-cannulation pulse means the limb is safe | Retrograde aortic flow also reverses the limb's residual native supply. And pulses are unreliable on non-pulsatile flow with vasopressors |
Treating an added drainage cannula as free | Differential flows and Y-connector turbulence promote circuit thrombosis; poor positioning increases recirculation |
12.10 Key points
- The arterial site determines whether differential hypoxaemia is possible at all. Femoral return is retrograde and creates a watershed; axillary, subclavian and central return are antegrade and do not.
- Femoro-femoral is the default in an emergency and the only realistic option during arrest — accepting retrograde flow, raised afterload and limb risk as the price of speed.
- Upper-body return gives antegrade flow, lower afterload and, with jugular drainage, a mobilisable patient — at the cost of surgery, an operating room, and upper-limb hyperperfusion risk.
- Central cannulation abolishes the watershed and allows direct LV venting, and is the natural choice in post-cardiotomy shock.
- Size the artery with ultrasound before choosing the cannula. Fr = diameter in mm × 3, then go 1–3 Fr smaller. The cannula must not fill the artery.
- Choose the arterial cannula for the vessel, not for the target flow.
- Place the distal perfusion wire before the arterial cannula — afterwards, distal flow is much lower and the procedure is much harder. Use a 6–9 Fr reinforced sheath; alternatives are retrograde posterior tibial, an end-to-side graft, or a chimney graft.
- Site a right radial arterial line at cannulation — it samples what the coronary and cerebral circulations receive.
- Both limbs need examining, and the question differs at each end: ischaemia below, hyperperfusion above.
- Carotid return carries a reported 5–10% risk of large watershed cerebral infarction — a figure that appears twice in near-identical wording and should be read as one claim, not two.
- Triple cannulation is an upgrade with costs: place the added cannula under live imaging, and expect turbulence at the Y-connector and possible recirculation.
- Where the patient allows it, cannulate in a controlled environment. Setting is part of technique.
[VERIFICATION REQUIRED] — open items in this chapter
- No randomised evidence underpins any recommendation in this chapter. Every technique, size and sequence is expert practice drawn from textbooks.
- The 5–10% watershed cerebral infarction figure for carotid cannulation appears in the ISCCM Manual and the J Thorac Dis review in near-identical wording, indicating a shared upstream source that has not been retrieved. Treat as a single unverified claim.
- Cannula sizes (23 cm femoral arterial length; 8 mm graft with 21–24 Fr cannula; 22–24 Fr aortic; 32–46 Fr two-stage venous; 6–8 mm Dacron graft; 6–9 Fr distal perfusion sheath; 5 Fr antegrade cannula) are reproduced as the sources state them. They are conventions, not validated specifications, and device instructions for use govern.
- The 1–3 Fr undersizing rule is from Taha and is stated there without a supporting study. The underlying Fr = mm × 3 relation is the same convention used in Chapter 5, where the ELSO ultrasound guidance gave it as a ceiling. Note the recurring transcription hazard: the project's Red Book text renders this convention incorrectly as "1 Fr = 3 mm" (see the book status file); the correct relation is 3 Fr = 1 mm.
- The 15–20 kg lower weight limit for femoral vessels is from the Red Book, without a supporting citation retrieved.
- The claim that controlled implantation yields greater success than emergent application is from the ISCCM Manual, without an effect size or citation retrieved.
- NIRS for early detection of limb ischaemia is described as "recently recommended" in the ISCCM Manual; the recommending body and evidence were not identified. Deferred to Chapter 17.
- The J Thorac Dis review is cited here as 2015;7(7):E166–E176, transcribed from the running header of the PDF in the project library; authors and DOI were not established.
Cross-references
- Chapter 3 — ECMO Configurations: the configuration notation and the aortic mixing zone in principle
- Chapter 5 — VV ECMO Cannulation: ultrasound guidance, wire and dilator discipline, securing, and the vessel-sizing convention this chapter reapplies to the artery
- Chapter 11 — VA ECMO: Indications and Patient Selection: whether to cannulate at all, and the aortic-regurgitation and peripheral-vascular-disease contraindications that constrain the choices here
- Chapter 13 — VA ECMO Haemodynamics: the mixing point, afterload and what the arterial waveform shows
- Chapter 15 — LV Distension and LV Unloading: including the venting options that central cannulation makes straightforward
- Chapter 16 — Differential Hypoxaemia / Harlequin Syndrome: why the right radial line is sited at cannulation
- Chapter 17 — Limb Ischaemia and Vascular Complications: monitoring, NIRS, and management of the complication this chapter is largely designed to prevent
- Chapter 18 — VA ECMO Weaning and Decannulation: including percutaneous closure devices and post-decannulation limb surveillance
- Chapters 19–20 — ECPR: cannulation during arrest, where the distal perfusion sequence is necessarily deferred
- Chapter 34 — Cannula Problems: malposition, migration and cannula-related vascular injury
References
- Extracorporeal Life Support: The ELSO Red Book, 6th edition, Chapter 4, Section 4, Surgical Cannulation for VA (VV) ECMO in Older Children and Adults. Indications for surgical cannulation; femoral positioning and incision choice; the hockey-stick extension; dissection to the common femoral bifurcation; the arterial-only cutdown; retrograde posterior tibial distal perfusion; the 15–20 kg lower limit.
- Taha AR, Caridi-Scheible M, Leiendecker E, et al. ECMO: A Practical Guide to Management, Chapter 7, ECMO Cannulation and Configuration. Vessel measurement and the Fr = mm × 3 sizing rule with 1–3 Fr undersizing; femoro-femoral cannula length; subclavian and axillary graft technique; central cannula sizes; percutaneous femoral artery technique; the distal perfusion cannula sequence and sheath choice; position confirmation. [VERIFICATION REQUIRED] — full editor list, publisher, year and page numbers not confirmed.
- ISCCM Manual of RRT and ECMO in ICU, Chapter 25 (Types of ECMO) and Chapter 30 (Cannulation, Priming and Initiation of ECMO). The watershed phenomenon and the right radial monitoring requirement; distal perfusion options; axillary hyperperfusion and compartment syndrome; central cannulation; carotid as an alternative site; triple cannulation (VVA and VAV) and live-imaging insertion; infection and controlled implantation; NIRS. [VERIFICATION REQUIRED] — edition, editors, year and page numbers not confirmed.
- Extracorporeal Membrane Oxygenation (ECMO): review of a lifesaving technology. J Thorac Dis. 2015;7(7):E166–E176. Peripheral VA cannulation approaches; distal perfusion; carotid and axillary alternatives. [VERIFICATION REQUIRED] — authors and DOI not established; citation transcribed from the PDF running header.
Chapter status
Drafted and audited 6 September 2026. Ten-pass quality control completed: clinical, physiology, evidence, citation, numerical, safety, contradiction, redundancy, bedside utility and literature-currency passes.
The organising choice in this chapter is to treat cannulation as the moment at which most of Part III's complications are either prevented or accepted — hence the emphasis on the arterial site as a physiological decision, the cannula-to-vessel ratio, the distal perfusion sequence, and the right radial line. Every quantitative figure is reproduced as its source states it, no citation or identifier has been reconstructed from memory, and one widely repeated statistic is explicitly flagged as a single claim appearing twice rather than independent corroboration.