(1677) Use of Botulinum Toxin in the Treatment of Vasopressor-Induced Limb Ischemia

Introduction: In patients with shock, vasopressors are essential treatment. However, use can lead to tissue ischemia. This case highlights a novel approach to vasopressor-induced limb ischemia by use of botulinum toxin.

Description: 79-year-old female with history of bilateral knee replacement presented after a fall. Right femur x-ray showed a dislocated right knee arthroplasty with the tibia anteriorly dislocated. The patient was taken to the operating room urgently. Postoperatively, the patient developed respiratory failure and blood loss requiring transfusion and multiple vasopressors. Although vasopressor doses were weaned off by hospital day 5, on hospital day 2 the patient developed mottling of her hands (worse on the left). Vasopressor-induced ischemia was suspected. Nitroglycerin and heat application were administered without improvement over the next day.
Botulinum toxin was then diluted and administered as seven 10-unit injections into the left hand. The patient tolerated the procedure well and had notable reduction in mottling by day 4.
On day 4, the patient’s right hand appeared to have worsening ischemia. Botulinum was administered using the same method used previously but on the right. However, there was minimal improvement in the right hand by day 5. No additional doses of botulinum were given.
The remainder of the patient’s hospital course was complicated by right lower extremity amputation on day 6 and acute renal failure requiring continuous renal replacement. She eventually underwent tracheostomy and was transferred to the medical floor. On hospital day 23, she developed tracheal bleeding leading to cardiac arrest and expired.

Discussion: This case report highlights that botulinum toxin may be utilized to treat vasopressor-induced limb ischemia. Botulinum cleaves part of a protein complex required for acetylcholine exocytosis at neuromuscular junctions, leading to smooth muscle relaxation and vasodilation. Alleviation of pain is also suspected to be due to vasodilation. The finding that left hand ischemia resolved but not the right suggests that there is a time dependent benefit, and that botulinum should be administered as soon as possible after ischemia diagnosis. However, additional studies are needed to validate these findings.