A strategy to conserve personal protective equipment while performing therapeutic plasma exchange in a patient with COVID-19.

The SARS‐CoV‐2 virus causes COVID‐19; globally, there have been over 4 million confirmed cases and counting. A preschool‐aged child (weight 20 kg) with COVID‐19 requiring mechanical ventilation developed post‐viral transverse myelitis and quadriplegia for which therapeutic plasma exchange (TPE) was requested after not responding to methylprednisolone and intravenous immunoglobulin with interval worsening of spinal magnetic resonance imaging. A series of seven 1.5 plasma volume TPE procedures with red cell prime and 5% albumin as the replacement solution was planned. A double‐lumen 7 F apheresis‐compatible central venous catheter was placed in the right femoral vein at the bedside (see Figure); this anatomic site was chosen at the discretion of the intensive care unit team. In an effort to conserve personal protective equipment (PPE), , we developed a unique strategy to perform TPE from outside the patient's intensive care unit room.

A 6 m (19.7 ft) sterile tubing set with 37.5 mL volume (ASTOTUBE PVC Extension Line, Stihler Electronic GmbH, Stuttgart, Germany), routinely used as part of the blood and infusion warming device (ASTOTHERM plus 220, Stihler Electronic GmbH, Stuttgart, Germany) accompanying TPE at our institution, was attached to both inlet and return lines (12 m additional length and 75 mL additional extracorporeal volume) on the TPE device (Spectra Optia Apheresis System, TerumoBCT, Lakewood, Colorado). A further additional 6 m tubing set was attached to a separate infusion pump to provide ACD‐A at the point where blood left the patient's femoral vein via central venous catheter to prevent clotting via a 4‐way stopcock (Discofix 4‐way stopcock, B. Braun Medical Inc., Bethlehem, Pennsylvania; see Figure); this additional tubing did not contain patient blood and thus did not contribute to the extracorporeal volume. The ACD‐A, inlet, and return lines utilized a total of 18 m additional tubing (see Figure). The patient's total maximum extracorporeal volume was 298 mL (TPE disposable kit, 185 mL; blood warmer sterile tubing set, 37.5 mL; additional 6 m inlet line sterile tubing set, 37.5 mL; additional 6 m return line sterile tubing set, 37.5 mL) and represented approximately 22% of total blood volume.

The intensive care unit nurse who was already caring for the patient performed all vascular access connections. The ACD‐A infusion pump rate was set at 2.2 mL/min/L total blood volume (180 mL/hr), whole blood‐to‐anticoagulant ratio on the TPE device was set at 40:1, and inlet rate was maintained at 35 to 40 mL/min. Intravenous calcium gluconate (4 g in 250 mL normal saline) was infused at 5 to 6 mL/kg/hr (100‐120 mL/hr). Ionized calcium via venous blood gas measurement was performed every 15 minutes and remained above the lower limit of normal (1.15 mmol/L) throughout the procedure. No visual evidence of clotting or hemolysis occurred in the tubing or TPE device (see Figure); of note, the patient was also anticoagulated with enoxaparin (0.5 mg/kg subcutaneously every 12 hours) for thromboprophylaxis as part of our institution's COVID‐19 treatment protocols. Pre‐ and post‐TPE concentrations of total serum IgM were measured to assess procedure exchange kinetics of the first 1.5 plasma volume TPE, and a decrease of 69% was observed after the procedure.

The first four TPE procedures were performed using this unique strategy. The patient had two repeat COVID‐19 nucleic acid tests performed over 48 hours after her fourth TPE and SARS‐CoV‐2 was not detected on either specimen; based on these new negative results, her subsequent TPE procedures did not utilize this unique strategy and were performed per our routine standard operating procedures. During all TPE procedures in her treatment series, the patient's vital signs remained stable, no adverse events were detected, and all TPE procedures were completed. The patient has had no improvement of her quadriplegia and still requires mechanical ventilatory support. This strategy allowed for successful performance of TPE while also conserving PPE and preventing possible SARS‐CoV‐2 transmission to our TPE device or apheresis team personnel. We intend to utilize this approach in other patients who are on droplet or airborne precautions.

CONFLICT OF INTEREST

The authors declare no potential conflict of interest.