Basics of PD prescription writing

Concerning the basics of PD prescription writing--and only the basics, since there's lots to say about this interesting topic--the minimum prescription should specify the following:

1. What kind of PD does the patient use: for the most part, we distinguish between CAPD (continuous ambulatory peritoneal dialysis, in which the individual manually performs fluid exchanges, often several times throughout the course of a day) versus CCPD (continuous cycling peritoneal dialysis, in which a PD "cycler" machine is used to perform automated exchanges, usually at night), though often components of both are part of the prescription.

2. How much fluid volume per bag? Usually either 2 Liter or 2.5 Liter bags are used.

3. What percentage of dextrose solution is used? I've included in a previous post the common color-coding scheme PD patients use to specify which solution they use; this is often invaluable because patients often know only what color bag they use, not the numerical value of how much dextrose is in their PD fluid. The higher the % of dextrose, the greater the amount of UF is generally achieved.

4. How many exchanges per day? For CAPD, this may be as simple as saying that a patient gets 4 exchanges a day. However, the answer may be more complicated for patients who use a cycler.

For example: a typical CAPD script might look like this: 2 Liters x 2.5% x 4 exchanges per day.

Another common dilemma encountered by renal fellows is what to do with CCPD patients who are admitted to the hospital, since cyclers are rarely available for inpatient use and patients do not always bring their own into the hospital. Generally, cycler regimens can be converted to CAPD regimens by calculating their total daily infusion volume and then dividing this by 4 exchanges per day.

Other details of the PD prescription worth mentioning: often one needs to distinguish between "low calcium" and "regular calcium" dialysates; some patients will regularly use heparin with each fill; and icodextrin is being increasingly used for individuals who fall into the "high transporter" category of PD patients.

Any questions? Your best bet is usually just to call the PD nurse on call--in my experience, they tend to know their individual patients extremely well, and can troubleshoot most technical issues relatively rapidly.