In this post, we continue with the Renal System series starting with Peritoneal
Dialysis
Now, before we start, be sure to download the free PDF study guide with this post
to enhance your learning. The link is listed here!
Peritoneal Dialysis
How does peritoneal dialysis work compared to hemodialysis? Well the peritoneum
acts as the dialyzing membrane (semipermeable membrane) to achieve dialysis and
the membrane is accessed by insertion of a PD catheter through the abdomen.
PD occurs via the transfer of fluid and solute from the bloodstream through the
peritoneum into the dialysate solution.
In order for PD to be efficient it still uses the process of osmosis, diffusion and
ultrafiltration.
The peritoneal membrane is large and porous, allowing solutes and fluid to move via
osmosis from an area of higher concentration in the body to an area of lower
concentration in the dialyzing fluid. The peritoneal cavity is rich in capillaries;
therefore, it provides ready access to the blood supply.
Contraindications to PD
There are conditions of a patient that won’t allow the option of PD. These are:
- Peritonitis
- Recent abdominal surgery
- Abdominal adhesions
- Other GI problems such as diverticulosis
Access for PD
Let’s go over more about how the access for Peritoneal Dialysis works. If you
remember from the previous video of hemodialysis, there are definitely major
differences.
A siliconized rubber catheter such as a Tenckhoff catheter is surgically inserted into
the patient’s peritoneal cavity to allow infusion of dialysis fluid; the catheter site is
covered by a sterile dressing that is changed daily and when soiled or wet.
The preferred insertion site is 3 to 5 cm below the umbilicus.
The catheter is tunneled under the skin, deep enough through the fat and muscle
tissue to the peritoneum. How does the catheter remain stable? It is stabilized with
inflatable Dacron cuffs in the muscle and under the skin.
Over a period of 1 to 2 weeks following insertion, fibroblasts and blood vessels grow
around the cuffs, fixing the catheter in place and providing an extra barrier against
dialysate leakage and bacterial invasion.
If the patient is scheduled for transplant surgery, the PD catheter may be either
removed or left in place if the need for dialysis is suspected post transplantation.
The Dialysate Solution
Dialysis involves dialysate solution. From the previous video, we remember that the
solution is sterile.
The solution contains electrolytes and minerals and has a specific osmolarity,
specific glucose concentration, and other medication additives as prescribed.
The higher the glucose concentration, the greater the hypertonicity and the amount
of fluid removed during a PD exchange.
What else could be added to the dialysate solution? Well if hyperkalemia is not a
problem, potassium may be added to each bag of dialysate solution. Heparin is
added to the dialysate solution to prevent clotting of the catheter. Prophylactic
antibiotics may be added to the dialysate solution to prevent peritonitis. And lastly,
Insulin may be added to the dialysate solution for the client with diabetes mellitus.
PD Infusion
Let's go over the most important concepts of PD infusion. Let's start by knowing
what 1 exchange is considered to be. It requires three processes which are infusion,
dwell and drain.
What is a Fill? A Fill is 1 to 2 Liters of dialysate that is infused by gravity into the
peritoneal space, which usually takes 10 to 20 minutes.
The Dwell time is the amount of time that the dialysate solution remains in the
peritoneal cavity that can last 20 to 30 minutes to 8 or more hours, depending on the
type of dialysis used. The drain, which is the outflow, means fluid drains out of the
body by gravity into the drainage bag.
Nursing Actions with PD Infusion
Interventions before treatment include:
- Monitoring vital signs.
- Monitoring daily weight on the same scale.
- Having the patient void, if possible.
- Assessing electrolyte and glucose levels.
- Assessing the peritoneal catheter dressing and site.
Interventions during treatment include:
- Monitoring vital signs.
- Monitoring for respiratory distress, pain, or discomfort.
- Monitoring for signs of pulmonary edema.
- Monitoring for hypotension and hypertension.
- Monitoring for malaise, nausea, and vomiting
- Assessing the catheter site dressing for wetness or bleeding.
- Monitoring dwell time as prescribed by the doctor
- Initiating outflow; turn the client from side to side if the outflow is slow to start
- Monitoring outflow, which should be a continuous stream after the clamp is
opened.
- Monitoring outflow for color and clarity.
- Monitoring intake and output accurately; if out-flow is less than inflow, the
difference is equal to the amount absorbed or retained by the client during
dialysis and should be counted as intake.
Crucial to know are the following:
- Never allow dwell time to extend beyond the doctor's prescription because
this increases the risk for hyperglycemia.
- An outflow greater than inflow as well as the appearance of bright red blood
or cloudiness in the outflow should be reported immediately
Types of PD
The two different types of PD are Continuous ambulatory peritoneal dialysis and
Automated peritoneal dialysis. Let's go over Continuous ambulatory peritoneal
dialysis first.
Continuous ambulatory peritoneal dialysis closely resembles renal function because
it is a continuous process. The pro is that it does not require a machine for the
procedure. It also promotes client independence.
How it works is that the patient performs self-dialysis 24 hours a day, 7 days a week.
Four dialysis cycles are usually administered in a 24-hour period, including an
overnight 8-hour dwell time.
Now let’s go over Automated peritoneal dialysis. Automated dialysis requires a
peritoneal cycling machine. The machine can be done as intermittent peritoneal
dialysis, continuous cycling peritoneal dialysis, or nightly peritoneal dialysis. The
main difference is that the exchanges are automated instead of manual.
Complications of Peritoneal Dialysis
Like all types of treatment options comes a few compilations.The most common and
important complications to know are peritonitis, abdominal pain, abnormal outflow
and insufficient outflow. Let's go over Peritonitis first.
Peritonitis is basically an Infection either in the catheter insertion site or the
peritoneum. The main nursing action is to monitor for signs and symptoms of
peritonitis which are fever, cloudy outflow, rebound abdominal tenderness,
abdominal pain, general malaise, nausea, and vomiting. Another sign of peritonitis
includes cloudy or opaque outflow which is an early sign of peritonitis.
So what is the first action you do when you suspect peritonitis? Take a moment to
think of the answer and pause here.
If peritonitis is suspected, obtain a sample for culture and sensitivity of the outflow to
determine the infective organism. Once the organism is determined, antibiotics may
be added to the dialysate.
What are ways to prevent infection?
One important way is maintaining meticulous sterile technique when connecting
and disconnecting PD solution bags and when caring for the catheter insertion site.
Also preventing the catheter insertion site dressing from becoming wet during care
of the client or the dialysis procedure; change the dressing if wet or soiled.
Okay let's go over the next complication of PD which is abdominal pain
What causes Abdominal pain in the first place?
Well the peritoneal irritation during inflow commonly causes major discomfort during the first few exchanges; the pain usually disappears after 1 to 2 weeks of dialysis treatments.
One way to help reduce pain is to warm the dialysate before administration, using a
special dialysate warmer pad, because the cold temperature of the dialysate can
cause discomfort.
The next complication is abnormal Outflow.
Any of the following signs indicate major issues. Here are a few examples:
- Bloody outflow after the first few exchanges indicates vascular complications
The outflow should be clear after the initial exchange.
- Brown outflow indicates bowel perforation.
- Urine-colored outflow indicates bladder perforation.
- Cloudy outflow indicates peritonitis.
The next complication to cover is Insufficient outflow. What is the main cause of insufficient outflow? It is usually from having a full colon. The most important nursing action is to encourage a high-fiber diet, because constipation can cause inflow and outflow problems. Stool softeners may be given if there is an order.
Besides a full colon, an insufficient outflow may also be caused by catheter
migration out of the peritoneal area. If this occurs, an x-ray will be prescribed to
evaluate catheter position.
Here are nursing actions to follow after treatment of an insufficient outflow:
- Maintain the drainage bag below the client's abdomen.
- Check for kinks in the tubing.
- Change the client’s outflow position by turning the client to a side-lying
position or ambulating a client.
- Check for fibrin clots in the tubing and milk the tubing to dislodge the clot as
prescribed.
In this post, we went over Peritoneal Dialysis and its contraindications. We also talked about the access for PD, PD infusion and nursing actions. Remember the type of different PDs and the complications.
So that concludes this post. As always, thanks for reading!