Temporary changes in hemodialysis parameters in patients affected by COVID-19 infection: A visual guide

Background: People dependent on unit HD are vulnerable to COVID-19. We describe the safety and outcomes of reducing HD frequency to minimise patient exposure to the virus. Methods: HD was reduced from thrice to twice-weekly in selected patients for 9 weeks from March 2020. Urine output, heart failure, fluid-overload, hyperkalaemia, medication and patient preference were considered. Patients were asked to restrict dietary potassium, salt and fluid. Selected patients reducing HD frequency received 10g onceweekly sodium zirconium cyclosilicate (SZC). Group 1: Continue thrice-weekly HD Group 2: Twice-weekly HD +SZC Group 3: Twice-weekly HD -SZC. Pre-HD serum potassium (sK+) and bicarbonate (sHCO3 -), systolic blood pressure (SBP) and weights were monitored. COVID-19 transmission, hospitalisation and death were recorded. Results: Of 77 patients (mean age 70 years, 74% male), 17 continued thrice-weekly HD. 60 patients reduced to twice-weekly HD, of which 43 received SZC. There were 494 fewer HD treatments over 9 weeks. There was no significant difference in mean monthly sK+ in any group between March (pre-intervention), April and May;but 6 patients returned to thrice-weekly HD early due to hyperkalaemia or fluid-overload. SZC was increased to 10g twice-weekly in 15 patients. There was a reduction in mean monthly sHCO3 -during twice-weekly HD. No changes were made to oral or HD bicarbonate prescriptions. There was no significant difference in pre-HD weight or SBP from baseline in patients dialysing twice-weekly. Only 2 of the 14 admissions over 9-weeks were related to hyperkalaemia or fluid-overload. 5 patients tested positive for COVID-19. 2 of the 3 deaths during this period were due to COVID-19. Both were elderly males with CVD and chronic respiratory disease. 1 patient died of a MI after returning home from HD. No deaths were attributed to a reduction in HD frequency. There was no evidence of COVID-19 transmission on the HD unit. No patients were transferred to the regional hub for HD due to COVID-19. Conclusions: Reducing HD frequency in carefully selected patients is safe, and with strict infection control and timely COVID-19 testing, can reduce COVID-19 transmission and patient transfer to HD hubs. Dietetic review and SZC can reduce hyperkalaemia. Improved documentation of urinary output and cardiac function would optimise this approach.