Contraindications for Nerve Blocks

Absolute Contraindications

Deep peripheral nerve blocks are absolutely contraindicated in patients taking P2Y12 inhibitors (clopidogrel, prasugrel, ticagrelor) unless discontinued 5-7 days prior to the procedure, as recommended by the American Society of Anesthesiologists 1, 2, 3, 4
Active P2Y12 inhibitor therapy (clopidogrel, prasugrel, ticagrelor) without appropriate discontinuation periods is a contraindication for deep/non-compressible blocks, with clopidogrel requiring 5-day discontinuation, prasugrel requiring 7-day discontinuation, and ticagrelor requiring 5-day discontinuation 1, 2, 3, 4
Therapeutic anticoagulation is a contraindication unless dabigatran concentration is ≤30 ng/mL or appropriate reversal (idarucizumab) is administered, according to the American College of Cardiology 5, 6
Coagulopathy or bleeding disorders that cannot be corrected are a contraindication for nerve blocks, as stated by the National Comprehensive Cancer Network 7
Patient refusal is an absolute contraindication for nerve blocks, as respected by the American Medical Association 7
Active infection at the injection site is a contraindication for nerve blocks, as recommended by the Centers for Disease Control and Prevention 7
Very short life expectancy is a contraindication for interventional pain procedures, according to the American Academy of Hospice and Palliative Medicine 7

Aspirin monotherapy is a relative contraindication for deep/high-risk blocks, and may proceed only if benefit/risk ratio is favorable, as assessed by the American Society of Regional Anesthesia and Pain Medicine 1, 2, 3, 4
Mono or dual antiplatelet therapy may be acceptable for superficial/low-risk blocks with favorable benefit/risk ratio, according to the American Heart Association 1, 2, 3, 4
COVID-19 infection is a relative contraindication for nasal sphenopalatine ganglion blocks due to aerosol generation risk, as recommended by the World Health Organization 8
Medications increasing bleeding risk, such as anticoagulants, antiplatelet agents, and antiangiogenesis agents, require careful assessment, as stated by the National Comprehensive Cancer Network 7
Respiratory compromise risk requires avoidance of blocks that may impair respiratory function, in favor of alternatives, according to the American Thoracic Society 8

Ultrasound guidance is mandatory for all nerve blocks to reduce local anesthetic systemic toxicity risk, as recommended by the American Society of Anesthesiologists 1, 2, 3, 4, 6
Experienced operator performing the technique is required for all nerve blocks, as stated by the American Board of Anesthesiology 1, 2, 3, 4
Calculated safe dose of local anesthetic based on patient weight is necessary for all nerve blocks, according to the American Society of Regional Anesthesia and Pain Medicine 6, 9
Immediate resuscitation equipment availability is required for all nerve blocks, as recommended by the American Heart Association 6, 9