Regional Anaesthesia in patients with potential coagulopathy

The risk of unintended complications from anaesthetic procedures includes vertebral canal haematomas (from epidural/spinal insertion) and perineural haematomas (after peripheral nerve blocks). Vertebral canal haematomas are rare but can cause devastating long term neurological deficit.

Patients arriving in field hospitals will not be on anticoagulants, but are subject to massive blood loss, massive transfusions and are often coagulopathic. Availability of ROTEM adds additional information that is not covered by other guidelines. This guideline aids the decision-making process using currently available information.

Epidural catheter insertion (also applies to single shot spinal techniques)

  1. Discuss and document clinical requirement (risk v benefit) between two senior clinicians. Where possible this should also be discussed with the patient.
  2. After large transfusions associated with use of FFP then epidural insertion is consultant only procedure – aim for least traumatic insertion[1].
  3. Insert epidural only when INR ≤ 1.5 and APTR ≤ 1.5[2] and platelets >80 x109/L[3].
  4. If platelets >80 x109/L epidural insertion must be deferred if CT>100s, MCF (Ex) <40 or MCF (Fib) <8 (expert opinion only – note 2).
  5. If already on prophylactic LMWH dose then epidural catheter should not be placed until >10hrs after last dose. Next dose should be delayed >4hrs after insertion2.

Epidural catheter removal

  1. Remove only when INR ≤ 1.4 and APTR ≤ 1.42 and platelets >80 x109/L3.
  2. IF ROTEM available then MCF should be in normal range before removal (no evidence).
  3. Catheter must be removed >10hrs after LMWH dose2.
  4. Subsequent dose of LMWH should be >2hrs after catheter removal2.

Deep peripheral nerve block (single/continuous – lumbar plexus/paravertebral)

As per epidural – insertion and catheter removal2,[4].

Lumbar plexus has risk of retroperitoneal haematoma requiring surgical evacuation. The paravertebral space is relatively avascular, but incompressible, so should be treated as per epidural.

Superficial peripheral nerve block (single/continuous)

  1. Superficial nerve block placement related bleeding/haematoma is not associated with long-term damage2 (multiple case reports within the ASRA guideline) and large case series demonstrate safe removal of CPNB catheters in patients treated with warfarin, LMWH and heparin4,[5].
  2. CPNB catheters have been placed in patients receiving therapeutic (high dose) LMWH[6].
  3. Ultrasound use may reduce the risk of accidental vascular puncture[7]
  4. Higher values of INR, APTR and lower platelet count can be accepted for placement of CPNB. There is no evidence to make numerical recommendations. The decision should be made on a risk/benefit analysis on an individual patient basis. RoTEM can be of help in this process.
  5. CPNB catheter must be removed >10hrs after LMWH dose.
  6. Subsequent dose of LMWH should be >2hrs after catheter removal.

Notes:

  1. Coagulation is dynamic – results should be less than 2hrs old or stable. Patient must be normothermic.
  2. There is no evidence to suggest which ROTEM values are safe for epidural insertion. An epidural or deep catheter must NOT be inserted if CT>100s, MCF (Ex)< 40mm, MCF(Fib) < 8mm. If ROTEM parameters are better than these values, clinical discretion must still be applied.
  3. Increased vigilance, including simple neurological observation and pain team review in accordance with SOI is required after insertion of any epidural or CPNB catheter.
  4. Clear documentation of discussion and values should be appropriately recorded.

Definitions:

CPNB – Continuous Peripheral Nerve Block (catheter)

LMWH – Low Molecular Weight Heparin

MCF (Ex) – platelet and fibrin dependent clotting test on RoTEM. An abnormal MCF (Ex) in the presence of a normal MCF (Fib) reflects reduced platelet function.

MCF (Fib) – Fibrin clot only. Low MCF (Fib) denotes fibrinogen or F XIII deficiency

MCF – Maximum Clot Firmness

RoTEM – Rotational Thromboelastogram, PentpharmGMBH, Munich, Germany

D J Connor

Surg Cdr RN

Revision date May 2011

[1] 10-30x increase in estimated incidence of vertebral canal haematoma with traumatic v atraumatic epidural insertion: Stafford-Smith M. Impaired haemostasis and regional anaesthesia. Can J Anaesth 1996;43: R129-141

[2] Horlocker TT, Wedel DJ, Rowlingson JC et al. Regional anaesthesia in the patient receiving antithrombotic or thrombolytic therapy (ASRAPM Evidence-Based Guidelines – 3rd edition). Reg Anaes Pain Med 2010;35: 64-101

[3]Samama CM, Djoudi R, Lecompte T, et al. Perioperative platelet transfusion: recommendations of the Agence Francaise de Securite Sanitaire des Produits de Sante (AFSSaPS) 2003. Can J Anaesth 2005;52: 30–7

[4]Buckenmaier CC III, Shields CH, Auton AA, et al. Continuous peripheral nerve block in combat casualties receiving low-molecular weight heparin. BJA 2006;97: 874–7

[5] Chelly JE. Schilling D. Thromboprophylaxis and peripheral nerve blocks in patients undergoing joint arthroplasty. J Arthroplasty. 2008;23(3): 350-4

[6] Plunkett AR. Buckenmaier CC. Safety of Multiple, Simultaneous Continuous Peripheral Nerve Block Catheters in a Patient Receiving Therapeutic Low-Molecular-Weight Heparin. Pain Medicine 2008;9(5): 624-7

[7] Bigeleisen P. Ultrasound-Guided Infraclavicular Block in an Anticoagulated and Anesthetized Patient. Anesth Analg 2007;104(5): 1285-7