Parenteral Nutrition Flashcards
What is PN
Nutrition delivery via intravenous route
* Total nutrition support = Total parenteral nutrition (TPN) when patient is NPO due to significant gut dysfunction
* Partial Nutrition Support-may be partially fed via GI tract
Parenteral Nutrition (PN) because IV nutrition can be partial or total nutrition support
Aims of PN
To provide nutritional requirements for adults & children
* Maintenance (adults, infants & children)
* Growth (infants & children)
A substitute for enteral feeding in circumstances where establishment of full enteral feeds is contraindicated or delayed for prolonged periods of time. This is particularly relevant in young infants and children where delays in ENT feeding could promote weight loss, lack of growth and malnutrition can contribute to permanent neuro-development delays.
Indications for PN use
- Significant Bowel dysfunction resulting in inability to achieve adequate enteral nutrition for > 7-10 days for adults; 4-5 days (children & adolescents) or 2-3 days (infants)
- Hypermetabolism (eg trauma, burns)
- Moderate-to-severe pancreatitis requiring bowel rest > 7 days
- Bowel dysfunction or may gut resection ( > 70%)
- Hemodynamic instability where high risk for mesenteric ischemia (eg Necrotizing enterocolitis in premature infants)
- Severe dysmotility leading to non-functioning GI tract
When is PN contraindicated?
- When the gut works: PN is contraindicated!!
- Previously well nourished adults where GI tract is expected to be functional in 7-10 days
- Prognosis does not warrant aggressive nutrition support (eg palliation; note TPN can be part of palliation in children; not typically in adults)
- Vascular access is severely compromised
What clinical condition warrent cautious use of PN?
- Severe Hyperglycemia
- Severe renal failure
- Multi-organ system failure
- Severe metabolic acidosis or alkalosis
- Hyperosmolality
- Severe electrolyte disturbances
What are complications of PN?
- Typically due to overfeeding and lack of GI stimulation
- Cholestatic liver disease (includes abnormal heptaic and biliary function and Liver steatosis) (most common in premature infants)
- PN associated cholelithiasis (due to decreased secretionof cholecystokin (CCK)
- Infection
PN induced liver disease
Severe disease common in infants & children (prematurity of birth) but can also see in adults. Can see changes within 2 weeks of initiation of PN. Risk Factors:
* Prematurity of birth
* Duration of PN
* Infection
* Lack of enteral stimulation
* Bacterial overgrowth
* Overfeeding
What can cause infection with the use of PN?
- Not following aseptic techniques - in preparation and inserting lines so other things get into circulation
- Central line infections ( closer to heart) - Systemic infections
EN or PN?
38 yr old woman POD # 6 spinal surgery. NPO. On high doses of pain meds. Abdomen distended, NG to suction with high output, no BM’s.
TPN
* high output of more than 2L and needs high IV hydration
EN or PN
78 yr old man POD # 6 back surgery. Minimal oral intake x 5 days. C/o nausea + dislike of hospital food. No vomiting. Requiring IV hydration for fluids and meds.
EN
* Only has minimal GI symptoms but GI is stilling and no NPO order
EN or PN
16 yr old girl with history of cerebral palsy, fed by G-J tube. Admitted with a small bowel obstruction. Surgery planned in 4 days.
Would want more information…
* She is young so would need TPN at 4-5 days
* Is likely NPO before this
* Would want to know her history and previous intake and if she is NPO right now
* She will be in the hospital for more than 4 days
* Would want to ask about Gi symptoms and if fluids are going through from G-J well
What are the routes for administering PN?
- IV’s can be in the arm ; depending on location can be either a central line or peripheral line
- IV’s in chest area; usually central lines
peripheral IV line
Peripheral IV line (PIV = peripheral venous line): Goes into smaller veins; can only give a small amount of nutrition (max 10% glucose can go in this line); 510 kcal/d
* usually last for 5-7 days; meant for short-term IV access (about 2-4 weeks??)
* Can only handle hypotonic or isoosmolar solutions
* Midline: peripheral IV access last up to two weeks
* Usually inserted in arm, feet or head; can be elsewhere (help with 2-4 week window)
central IV line
Central IV line (CVL = central venous line): Goes into bigger veins-more concentrated nutrition can be delivered via this method
* May last for months or years
* Can handle hypertonic solutions
* Multiple types
* Typically inserted into chest, arm or leg (eg femoral vein) typically bigger, central vein
* Eg. port-a-catheters, Hickman, Broviacs, PICC line (all are CVL).
What are portacatheters?
- Access device: Central Line
- Located under the skin in the chest wall
- Often used when only need intermittent intravenous access (eg patients on chemotherapy and on and off during multiple cycles)
PN osmolarity
- central line - high osmolarity
- peripheral line - low osmolarity
