We thank you for your question. The context of your question is a little unclear. In general, in medicine, the abbreviation SOB refers to shortness of breath. For patients with chronic kidney disease stage 5 on home peritoneal dialysis (PD), shortness of breath can be related to fluid overload. The reasons for fluid overload are multiple and include: inadequate fluid removal on peritoneal dialysis, excess fluid and/or salt intake, and loss of residual kidney function. Interventions depend on the cause for the fluid overload. I would recommend looking at this on-line document written for nurses caring for patients on PD (see page 19).
 
Nova Scotia Health Authority Renal Program, Clinical Nurse Educators: Learning Module for Peritoneal Dialysis (PD): Nursing Beyond Entry Level Competency (BEL). Updated September 20, 2018. Available at:
http://policy.nshealth.ca/Site_Published/nsha/document_render.aspx?documentRender.IdType=31&documentRender.GenericField=1&documentRender.Id=70822