Aquapheresis: An Institutional Experience

Aquapheresis (AQ) consists of the extracorporeal extraction of plasma water from the vascular space across a semipermeable membrane in response to a transmembrane pressure gradient. The primary utilization of AQ has been in the management of patients with diuretic resistant heart failure with a treatment goal directed to quickly eliminate the excess fluid and optimize volume status. This modality is similar to isolated ultrafiltration performed on those patients requiring dialysis, but utilizes a machine that is smaller and easier to initiate and operate compared with traditional dialysis equipment.

A retrospective study that describes the indications in which AQ was utilized at Lenox Hill Hospital. The patient list was generated by searching for the keyword "Aquaph" in our electronic health record (EHR) orders. Patients were categorized based on hospital location and indication of AQ therapy. Additional information includes duration of treatment (days), changes in creatinine (start of AQ to stop of AQ), and total volume removed.

The search generated 28 patients; five were excluded as AQ was not initiated. In the remaining 23 patients, the mean aquapheretic volume per day was 1954 mls, with no significant change in creatinine. Indications for AQ broke out into five main categories: cardiogenic shock including post cardiothoracic procedure (10 pts); anasarca (5 pts); ATN with volume overload (4 pts); ESKD with bridge ultrafiltration between hemodialysis treatments (2 pts); and post-op volume overload (2 pts).

We found that aquapheresis can be utilized in situations other than diuretic resistant heart failure. Also to consider, is the ease in which this less complicated aquapheresis equipment can be operated compared to the more complex hemodialysis equipment.