Malfunctioning Temporary Hemodialysis Catheters in Patients with COVID-19

Kanitra, John J.; Power, Alexandra D.; Hayward, R. David; Haouilou, Jimmy C.; Edhayan, Elango

OBJECTIVE: The hypercoagulability seen in COVID-19 patients likely contributes to the high Temporary Hemodialysis Catheter (THDC) malfunction rate. We aim to evaluate prophylactic measures and their association with THDC patency. METHODS: A retrospective chart review of our institutions COVID-19 positive patients who required placement of a THDC between February 1 to April 30, 2020 was performed. The association between heparin locking, increased dosing of venous thromboembolism (VTE) prophylaxis and systemic anticoagulation on THDC patency was assessed. Proportional hazards modeling was used to perform a survival analysis to estimate the likelihood and timing of THDC malfunction with the three different prophylactic measures. We also determined the mortality, rate of THDC malfunction and its association with D-dimer levels. RESULTS: A total of 48 patients with a mortality rate of 71% were identified. THDC malfunction occurred in 31.3% of patients. Thirty-seven patients (77.1%) received heparin locking, 22 (45.8%) received systemic anticoagulation and 38 (79.1%) received VTE prophylaxis. Overall rate of THDC malfunction was lower at a trend level of significance, with heparin vs. saline locking (24.3% vs. 54.6%, p=0.058). The likelihood of THDC malfunction in the heparin locked group is lower than all other groups (Hazards ratio [HR]= 0.07, 95% CI [0.01, 0.45], p=0.005). The rate of malfunction in patients with subcutaneous heparin (SQH) 7,500 units three times daily (TID) is significantly lower than of the rate for patients receiving none (HR=0.03, 95% CI [0.001, 0.74], p=0.032). A trend level significant association was found for SQH 5,000 units vs none (p=0.417) and SQH 7,500 vs 5,000 units (p=0.059). Systemic anticoagulation did not affect THDC malfunction rate (p=0.240). Higher D-dimer levels were related to greater mortality (HR=3.28, 95% CI [1.16, 9.28], p=0.025), but were not significantly associated with THDC malfunction (HR=1.79, 95% CI [0.42, 7.71], p=0.434). CONCLUSIONS: Locking THDC’s with heparin is associated with a lower malfunction rate. Prospective randomized studies will be needed to confirm these findings to recommend locking THDC with heparin in COVID-19 patients. Increased VTE prophylaxis suggested a possible association with improved THDC patency, though the comparison lacked sufficient statistical power.