Venous Limb Gangrene and Pulseless Electrical Activity (PEA) Cardiac Arrest During Management of Deep‐vein Thrombosis and Progressive Limb Ischemic Necrosis Following Vascular Surgery

A 55-year-old male former smoker was admitted urgently to hospital by his vascular surgeon for further investigation and treatment of an ischemic right lower limb. The patient had undergone 34 days earlier right femoral-posterior tibial bypass surgery using the greater saphenous vein as a graft. On postoperative day (POD) 1, revision surgery was required because of early graft occlusion. He was discharged to home on POD4 on oral aspirin (81 mg/day). At the first postoperative visit (POD20), the patient had a painful, discolored right foot; arterial pulses were intact, but venous ultrasound revealed right soleal/peroneal deep-vein thrombosis (DVT). Rivaroxaban, 15 mg twice-daily orally, was started, and aspirin continued. Despite this treatment, 2 weeks later (POD34) the patient had ongoing pain with progression to foot necrosis (Figure 1), prompting vascular surgeon reassessment and hospitalization. The patient stated he was compliant with taking rivaroxaban, including specific mention of taking the medication with food, as recommended. Admission hemoglobin was 12.3 g/dL, white blood count 14.0 × 10/L (neutrophils, 10.6 × 10/ L), and the platelet count was 1042 × 10/L. This patient has ischemic limb necrosis in the setting of recently diagnosed DVT that occurred within the first few weeks following arterial bypass graft surgery performed for peripheral arterial occlusive disease. There are several unusual aspects to the case. For example, despite preceding arterial revascularization and clinically evident right foot necrosis, the arterial pulses are palpable. This raises the possibility of small artery disease, perhaps due to cholesterol embolism syndrome or localized recurrent graft-related arterial microcirculatory occlusion. However, as lower limb DVT was recently diagnosed in the same limb, another possible diagnosis is venous limb gangrene, that is, distal ischemic necrosis secondary to microvascular thrombosis in a limb with acute DVT. However, venous limb gangrene usually occurs in the setting of disseminated intravascular coagulation (DIC) secondary to heparin-induced thrombocytopenia (HIT) or metastatic adenocarcinoma. Moreover, the patientʼs platelet count was unexpectedly high (1042 × 10/L). Although the platelet count typically increases post-surgery, a phenomenon called postoperative thrombocytosis, peak platelet counts are usually observed by approximately day 14, with return to baseline (preoperative) platelet count values by about day 30. Thus, the patientʼs greatly elevated platelet count on POD34 is striking and requires explanation. The patient underwent CT angiography, which showed patency of the arterial bypass and the distal arteries. However, there was an incidental finding of a new left popliteal DVT that was asymptomatic. Repeat right leg venous duplex ultrasound showed unchanged soleal/ peroneal DVT, but there was new right distal posterior tibial vein thrombosis. Although absence of large artery occlusion on imaging does not completely exclude the possibility of distal arterial (microcirculatory) occlusion, the demonstration of new DVT in the ischemic limb continues to suggest venous limb gangrene. Another puzzling issue is the additional finding of a new contralateral limb DVT, suggesting an Received: 24 January 2020 Revised: 21 February 2020 Accepted: 27 February 2020