Which of these clients is a priority to assess?

A client who is receiving an initial round of peritoneal dialysis, who complains of mild cramping with instillation of dialysate fluid.

A client who is preparing for hemodialysis in one hour and is presenting with heart rate 100 bpm, blood pressure 160/92, and weight increase of 2kg/48 hours.

A client who has begun hemodialysis and is presenting with nausea, vomiting, change in level of consciousness, and agitation.

A client who is receiving peritoneal dialysis with an order to infuse in 500 mL of dialysate and only drains out 450 mL.