Parenterals 3 Flashcards
What are the 2 specialized large volume parenterals?
peritoneal dialysis solutions and parenteral nutrition solution
Explain peritoneal dialysis?
- a large bore catheter placed into the abdominal cavity
- placement is through a tunnel and the catheter usually has 2 dacron cuffs to seal the tunnel from microorganisms and leaks
What are the 5 stages of dialysis?
- hookup
- infusion
- diffusion (fresh)
- diffusion (waste)
- drainage
What is CAPD?
continuous ambulatory peritoneal dialysis
How does continuous ambulatory peritoneal dialysis work?
- uses soft catheters with 1 mm perforations and slots to allow fluid replacement and removal
- catheter placement is a surgical procedure with some risk of complications:
- bladder perforations, hemorrhage, hydrothorax, peritonitis, tunnel infection or bowel perforation
How many litres of fluid are ran throughout the abdominal cavity in the process of dialysis?
2 liters
What is the process of continuous ambulatory peritoneal dialysis?
- two litres of fluid are run throughout the abdominal cavity
- catheter is sceptically capped and fluid remains in place for 4-6 hours
- waste materials and water from the blood establish an equilibrium with the fluid
- fluid is then drained out via the catheter into an empty bag
- the usual daily fluid is 8 L
What do dialysis solutions usually contain?
- sodium, magnesium, calcium and lactate (about the same concentrations found in blood)
What concentration determines the amount of water that will be removed from the patient?
dextrose content
What controls the exchange of fluid and waste in dialysis?
peritoneal membrane
Peritoneal dialysis is not effective in removing what mineral?What is used for this?
- phosphate
- antacid tablets are generally used as they are phosphate binders (aluminum hydroxide is usually used)
What is the most common complication of peritoneal dialysis?
infection - need to have a good aseptic technique when handling solutions and proper care of catheter exit sites are essential in avoiding infections
What is parenteral nutrition?
the intravenous administration of water, nitrogen, calories, electrolytes, vitamins and trace metals in amounts appropriate to achieve an anabolic state in patients who cannot eat or cannot eat enough to maintain life
Who are candidates for parenteral nutrition?
- those who are severely malnourished and those who have a dysfunctional GI tract for more than 5-7 days
- patients with post-surgery complications, sever trauma, severe burns, IBS, chemotherapy and short gut syndrome . Preterm infants also get this
What are the energy requirements for adults?
30-50 kcal/kg/day
How is total daily requirement calculated?
resting energy expenditure (REE) x activity x injury factors
What equation is resting energy expenditure calculated from?
Harris-Benedict equation
What else can energy requirements be determined from?
oxygen consumption and CO2 production
What are the calorie sources that are used in parenteral nutrition?
- carbohydrate
- fat
Carbohydrate calories in excess can cause damage to what vital organ and high production of what?
can damage the liver and cause high production of CO2
If more than ___ of dextrose is given, hyperglycemia will result with high volume diuresis
5 mg/kg/minute
What are the fluid requirements of neonates?
100-150 mL/kg/day
Peritoneal nutrient mixture tends to be quite hypertonic and may contain as much as 25% ___ and 5% ___ so administration through a suitable large vein is required
dextrose
amino acids
What is nitrogen provided as in a peritoneal nutrient mixture?
provided as a picture of amino acids
(requirements vary with patients but usually ran from 0.16-0.32 g/kg/day
Nitrogen output can be estimated from what?
Urinary urea nitrogen - accounts for 85% of total nitrogen output – we want a slight positive balance in most cases
Why should we expect a temporary drop in serum levels when anabolic state is reached?
- since K and P are intracellular electrolytes
What vitamin is controversial in being needed via parenteral nutrition?
vitamin D
What minerals are added to the parenteral nutrition bag?
zinc, copper, manganese, chromium
What are the complications of the dialysate and parenteral nutrition?
- several related to the catheter (thrombosis, occlusion, phlebitis)
- infection at access site (catheter removal and antibiotic therapy may be required)
- metabolic complications may occur (electrolyte imbalances, fluid imbalance, acidosis, alkalosis, hypo and hyperglycaemia, liver abnormalities
