Fluids Flashcards
Types of fluid, Parental nutrition
Describe the different body fluid compartments within the body.
Fluid is stored within two main stores in the body:
Intracellular fluid (fluid within cells)
Extracellular fluid (outside of cells)
How much fluid is stored in the different body fluid compartments in the body?
Intracellular fluid (25L)
Extracellular fluids (15L)
- Plasma (3L)
- Interstitial fluid (12L)
Therefore total for about a 70kg person is 40L
What is the purpose of intracellular fluid store?
Give the cell structure in addition to facilitating metabolic processes that occur inside the cell
Describe the water balance within the body.
Usually kept relatively balanced in the body.
Intakes:
Fluids 1500mL
Food 800mL
Carbohydrate metabolism 300mL
Output:
Sensible losses: Urine 1500mL
Stools 200mL
Insensible losses (sweat or respiration): 900mL
What is meant by sensible losses?
Sensible fluid losses are losses that can be seen, felt or measured, such as urine output. Fluid loss through respiration cannot be easily measured and so is known as an insensible loss.
By understanding the daily fluid balance, how much fluid does an average person require?
25-30mL/kg/day
Which substances are able cross the cell membranes to different fluid compartments and which are unable to?
Water, small molecules are able to cross the semi-permeable cell membrane whereas larger colloidal substances and proteins are unable to move freely across from different fluid compartments.
The free movement of smaller molecules ensures that nutrients are able to move into cells and waste products can move out.
There is tight regulation of electrolytes contained within cells. Sodium and potassium concentrations for example are tightly regulated and controlled by a sodium/potassium Na+/K+ ATPase.
What does the Na+/K+ ATPase do?
For every ATP molecule, 3 sodium ions are exported from the cell whilst 2 potassium ions are imported.
What is the plasma, interstitial and intracellular concentration for sodium?
Plasma concentration: 142 mmol/L
Interstitial fluid: 145 mmol/L
Intracellular: 12 mmol/L
What is the plasma, interstitial and intracellular concentration for potassium?
Plasma concentration: 4 mmol/L
Interstitial fluid: 4.1 mmol/L
Intracellular: 150 mmol/L
What is the plasma, interstitial and intracellular concentration for chloride?
Plasma concentration: 103 mmol/L
Interstitial fluid: 113 mmol/L
Intracellular: 4 mmol/L
What is the plasma, interstitial and intracellular concentration for bicarbonate?
Plasma concentration: 25 mmol/L
Interstitial fluid: 27 mmol/L
Intracellular: 12 mmol/L
Which electrolyte is responsible for distribution of fluid?
Sodium increases the osmotic pressure, causing an increase in extravascular fluid (fluid retention).
What are some of the other fluids in the body that can have different concentrations of electrolytes?
Saliva
Gastric juice
Small intestine
Bile
Colon and diarrhoea
Sweat
Therefore if a patient has any condition that causes excess fluid loss of one of these stores you may have to adjust the electrolytes within the fluid bag.
What does maintaining fluid balance involve?
-Monitoring the fluid input and output
-That the daily normal requirements are maintained
-In addition to the normal requirements ensure that any additional losses are also compensated for.
What is the homeostatic system which ensures volume homeostasis?
The renin angiotensin system which is activated when there is a drop in renal perfusion. RAAS leads to the production of Angiotensin two which triggers the adrenal glands to release aldosterone and your pituitary gland to release antidiuretic hormone.
Aldosterone causes sodium and water retention and anti-diuretic hormone causes a reduction in the renal excretion of water and also increases thirst.
When may the RAAS not work as well?
After injury, illness or surgery
Which conditions would cause an reduction in fluid requirements?
Renal impairment
Liver impairment
Cardiac failure
Head injury (intracranial pressure increase)
Which conditions would cause an increase in fluid requirements?
Vomiting/diarrhoea
High output stomas (compensate for the loss of fluids)
Fistulas (connection of the gut)
Burns (skin is a barrier to fluid loss)
When is IV fluids indicated?
To correct acute losses of fluid or maintain homeostasis such as after:
Blood loss
Fluid loss
Maintain organ perfusion (inadequate perfusion of the kidney) and function
When there is a prolonged failure of oral intake (mucositis as a result of chemotherapy)
Excessive losses
Nil by mouth (maintain kidney function after anaesthesia)
Special case patients - burns, brain injury, children
What are some of the consequences if fluid balance is incorrect?
Electrolyte imbalance (and the clinical consequences of this- arrhythmias)
Peripheral oedema
Pulmonary oedema
Renal impairment
Acid/base disturbance
What are some of the clinical observations of fluid depletion?
Weight loss
Reduced blood pressure
Rapid, shallow breaths
Tachycardia, weak pulses - to maintain cardiac output
Reduced, concentrated urine
Reduced skin turgor (elasticity)
Thirst
Raised temperature
Increased capillary refill time
What needs to be reminded in terms of drug therapy and dehydration?
Some drugs may mask the symptoms of dehydration. Tachycardia is an example of dehydration, in a patient taking beta blockers they may not experience the symptoms of tachycardia when they are dehydrated.
What are some of the clinical observations of fluid overload?
Weight gain
Normal or raised blood pressure
Rapid, moist cough (pulmonary oedema)
Rapid pulse
Increased or decreased urine output
Oedematous skin
No change in thirst or temperature
State the three main types of fluids.
Crystalloids
Colloids
Blood
How are fluids categorised by?
Compositions of fluid
Mechanisms of distribution - where is the fluid going to go in the body (links to causes of fluid depletion)
Why can’t water can infused into the body?
Water is not isotonic with body fluid, so would cause haemolysis (breakdown of red blood cells) and is painful.
What are crystalloids made up of?
Small molecules in water, normally this is ions such as sodium and chlorine and/or glucose.
What are some examples of crystalloid fluids?
0.9% Sodium chloride
5% Glucose
Dextrose-saline
Hartmann’s
What are colloid fluids made up of?
Dispersions of large organic molecules in a carrier solution
What are some examples of colloid fluids?
Albumin
Dextran
Gelatin
Which electrolyte present in crystalloids fluids determines the fluid distribution in the body?
Crystalloid fluid with a high sodium content, more fluid is retained within the extracellular space and so is known as a ‘plasma expander’, essentially expands the blood ensuring adequate perfusion throughout the body. This is useful if you have lost blood.
Crystalloid fluid with a lower sodium content distributes more evenly through the total body water so not just in the extravascular space.
What is one of the main cautions for use of crystalloid materials?
Hypernatremia
What are some of the properties of sodium chloride 0.9% solution?
9 grams/150mmol of Na+ and chloride in 100mL
The solution is completely distributed into the whole extracellular space, both intravascular and interstitial spaces and is used as a plasma expander
How can sodium chloride administered?
Either s/c or IV
What are some of the main cautions associated with sodium chloride use?
Hypernatremia and Hyperchloraemic acidosis with excess use
How is glucose 5% distributed in the body?
Throughout the intravascular, interstitial and intracellular compartments and is the same as giving water
It is not a plasma expander as it is primarily metabolised
What does Dextrose Saline contain?
Glucose and Sodium chloride
Usually as a 4% (Glucose) / 0.18% (Sodium chloride)
Can Dextrose Saline be used long-term?
No as it does not contain other electrolytes
What is the infusion rate of Dextrose Saline?
3L over a 24 period
Which volume does Dextrose Saline increase?
Intravascular volume
Which crystalloid material is the most similar to plasma?
Hartmann’s
In terms of sodium, potassium, bicarbonate, chloride, calcium, pH and osmolality
Does Hartmann’s solution contain glucose?
It does not contain glucose
When is Hartmann’s solution indicated?
For routine maintenance
In resuscitation
For patient’s when large volumes are required or in patients with impaired compensatory mechanisms
What are some of the chemical compositions and properties of colloid fluids?
They are solutions of large insoluble molecules
Characterised depending on molecular size
Contribute to oncotic pressure
Define the oncotic pressure.
It is the osmotic pressure exerted by proteins in blood plasma that usually tends to pull water into circulatory system (hence causing plasma expansion)
Does colloids or crystalloid fluids cause more volume expansion?
Colloid fluids, colloids remain in the extracellular space initially causing plasma expansion.
What are some of the properties of albumin?
4.5% isotonic
20% hypertonic
It has a short duration of action
Expensive and derived from human serum
What is the advantage of using 20% hypertonic albumin?
When there is a need for plasma expansion, hypertonic solution has the extra benefit of osmotically drawing in more water into the plasma therefore having an added benefit
When is albumin indicated?
Burns, Haemorrhage, Surgical losses and trauma, often used in intensive care
What are the two types of synthetic colloids?
Dextrans
Gelatin derivatives
What does the duration of action of colloids depend on?
Their molecular size
What are some of the properties of Dextrans?
It is a poly-dispersed solution, an example include Dextran 70. Dextran comes in different molecular weights, the higher the molecular weight the longer the duration of action.
What are some of the disadvantages associated with Dextrans?
Interferes with blood clotting, allergic reactions and cross matching with blood
Can cause anaphylaxis
The drug is renally excreted and therefore patient must have reasonable renal function.
What type of fluid is Gelatin?
Complex carbohydrate molecule
What are the two main types of Gelatin?
Modified gelatin (Gelofusine)
Polygelines (Haemaccel)
Difference in molecular size Gelofusine > Haemaccel
What are some of the properties of Gelatin?
Potential for anaphylactic reactions (derived from animals)
Contributes to the osmotic force
What are the main advantages of crystalloids?
Maintain osmotic gradient
Widely available
Low risk of ADRs
Inexpensive
What are the main advantages of colloids?
Smaller volumes (1L equals 3L of crystalloids, same plasma expansion)
Faster to give
Longer half life
Starches can reduce capillary leaks into interstitial space from intravascular compartment - during the initial stages of inflammation (increase in vascular permeability) - fluid requirements change drastically.
In a patient who is fluid restricted (Heart failure, Renal failure) which type of fluid would you give?
Colloids, as smaller volumes of colloid fluids are required to achieve the same plasma expansion as crystalloid fluids.
(1 litre of colloid fluid achieves the same plasma expansion as giving 3 litres of crystalloid fluid)
What are the disadvantages of crystalloid fluids?
Poor in maintaining oncotic pressure
Short half life
What are the disadvantages of colloids fluids?
Maximum volume per day
ADRs- itching
Expensive
When is blood used?
When the blood loss by haemorrhage exceeds 20% of the total blood volume
If up to 20% of blood volume is lost what is used?
Crystalloid
Colloid
What type of blood is available?
Whole blood:
Complete replacement
Packed cells :
Removal of platelets, concentrated white and red.
Same oxygen carrying capacity but not plasma expansion.
Good if you are fluid restricted
Plasma:
Contains water, electrolytes, proteins, clotting factors after red blood cells removed
Used in patients with blood or clotting disorders
What are some of the complications associated with inappropriate fluid use?
Heart failure
Acute respiratory distress syndrome
Biochemical abnormalities
Allergic reactions
Haemodilution
Dilutional coagulopathy
Renal impairment
What are the 5Rs and what are they used for?
Resuscitation
Routine maintenance
Replacement
Redistribution
Reassessment
What should be considered at all times when prescribing intravenous fluids in adults
What is resuscitation and what is the purpose of fluid replacement in such patients?
Any condition where there is acute circulatory shock, there is a decrease in intravascular fluids.
The main of IV fluids in such cases is to restore circulatory blood flow and cardiac output
What is the rate of fluid resuscitation?
500ml bolus of crystalloid over 15 mins
0.9% NaCl 500mL over 10-15 mins (130-154 mmol)
Repeat as necessary up to 2L
Monitor closely for changes in blood pressure
When is routine maintenance used?
After resuscitation, when patients are going to need fluids - such as post op
What is the dose of IV fluid used in routine maintenance?
25-30ml/kg/day (maximum 2.5L, if obese use ideal body weight)
Up to 1mmol/kg/day of K+, Na+ and Cl-
50-100 grams a day of glucose
Example of a fluid used for routine maintenance?
4% Glucose/0.18% Sodium Chloride +
20mmol potassium chloride 500ml over 8hrs x 2
What is involved in the replacement and the redistribution part of the 5Rs?
These two aspects needs to be considered when calculating the ongoing routine maintenance requirements
Replacement: adjust IV prescription for electrolyte deficits for any ongoing losses in the context of the patient’s condition
Redistribution: adjust for any redistribution of fluids into different body fluid stores (3rd degree losses) such as during the early stages of inflammation (leakage into the interstitial fluids) or ascites (accumulation of fluid in the peritoneal cavity). It may be appropriate to switch the type of fluid used (colloid due to starch)
What is the importance of reassessment?
Should be reassessed at least daily, have their requirements changed?
Monitor for adverse effects
What were some of the problems associated with potassium chloride?
Firstly the ampoules of KCl that were used for fluids amongst other things were very similar in appearance to water for injection or sodium chloride (often used to reconstitute powders for injection or clean IV lines).
When used inappropriately this can cause cardiac arrest - arrhythmias.
Potassium is heavier and unless mixed appropriately, unevenly distributed in the bag and is injected straight into the patient.
To overcome this pre-mixed bags of potassium should be used where possible.
When the ampoules are used, hospitals were enforced to alert staff to their issue:
Treating KCl as a controlled drug
Packaging also alerted staff to their issue
Must be stored separately
What are the three routes of IV fluid administration?
Fore arm
Back of the hand
Small vein
Appropriate for short term use, replace every 24 hours
When is central venous access used?
Long term fluids: Longer than 10 days
When there is poor peripheral access (higher strength fluids can damage the veins)
What is used in central venous access?
Peripherally inserted central catheter
When is s/c (hypodermoclysis) used?
IV fluids only used for IV use, so this is a ‘off label’ use
Used for prolonged administration of fluids
Palliative care
Easier to insert lines
Only for slow administration
What are the important pharmaceutical care issues associated with fluids?
Patient should have an “IV fluid management
plan” – not “bag by bag”
Is reviewed daily by an expert
Review at same time as other prescribed
medicines
Only prescribe 24 hours at a time - fluid status can change by the hour
What is malnutrition associated with?
It is associated with deficiencies in:
Nutrient intake
Digestion
Absorption
Metabolism
Excretion/ Nutrition losses
What are some of the consequences if malnutrition is untreated?
Gross structural and functional changes
Quality of life is reduced
What are some of the conditions you would associated with acute and chronic malnutrition?
Acute malnutrition: develops rapidly in
Acute stress or injury
Chronic malnutrition:
Cancer, organ failure, IBD
Requires long term monitoring and therapy
What are the consequences of untreated malnutrition?
Impaired immunity
Decreased wound healing
Increased complications
Poor response to medical or surgical
therapy (3 times more likely to get complications from surgery if malnourished)
Reduced growth or development of infant or child
Death
If a patient is malnourished what are some of the possible interventions that should be made?
Ensuring the provision of food and water - this could include helping patients (such as elderly patients) with the administration of food
Increasing oral intake (such as high supplement drinks)
Enteral
Parental tubes
When would you consider enteral feeding?
A patient is malnourished or at risk plus
Inadequate or unsafe oral intake plus
Functioning accessible GI tract
When would you consider parental feeding (IV)?
A patient is malnourished or at risk plus
Inadequate or unsafe oral intake or enteral intake plus
Non-functioning or perforated GI tract
What is included in parental feeding?
◼ Water
◼ Amino acids
◼ Glucose
◼ Lipids
◼ Vitamins
◼ Trace elements
◼ Electrolytes
Is parental nutrition used to fulfil the total parental requirements?
Often it is but it can also be used a supplement to an enteral feed or diet
What are the reasons for using parental nutrition short term in patients?
Post surgery if a patient is nil by mouth for more than 7 days (up to seven days can just give IV fluids - doesn’t have the calories needed for long term)
Obstruction in the gut
Severe shock if gut infection
Malnourished for unable to eat
What are the reasons for long term parental nutrition?
Non-functioning gut
No enough gut to function (surgery)
Some patients may be able to eat in small amounts
May or may not be permanent
What is the role if the multidisciplinary nutrition team?
Take daily referrals for PN from wards
Assess patient’s suitability for TPN
Assess patient’s nutritional requirements
Work out what combination is required & order from pharmacy
Assess inpatients on PN daily
How do parental nutrition bags differ to that of the oral diet?
Whilst some components remain the same for both such as water, vitamins and electrolytes, there are some components are substitutes in the parental nutrition bag from the oral diet.
Protein is switched to L-amino acid mixture
Carbohydrates are switched to glucose
Fat with essential fatty acids is switched to a lipid emulsion with essential fatty acids
Minerals are switched to trace elements
How do you calculate the water volume required for a TPN bag?
20-40ml/kg/day or
Maintenance fluid:
1500ml + (20ml x each kg of weight >20kg)
Then adjust for losses
What are some of the factors that would increase the volume intake, above their usual requirements?
Fever
Acute anabolic state
High temperature
Low humidity
G.I. losses
Burns/wounds
Blood loss
What are some of the factors that would decrease the volume intake, below their usual requirements?
High humidity
Blood transfusion
Drugs
Cardiac failure
Renal failure
Of the 20 amino acids, how many need to be included in TPN bags?
8 are essential, they cannot be synthesised by the body and must come for an external source
5 out of the remaining 12 are conditionally essential, meaning that in terms of ill health these are exceeded and therefore must also be given from an external source
What are some of the amino acids sources that are available?
Synthamin, Vamin, Vaminolact (paediatric)
What different strengths of nitrogen are available?
9 grams, 11 grams, 14 grams or 18 grams
What is the requirements to achieve a nitrogen balance?
Most adults require:
0.2 grams of nitrogen per kg per day
What is the problem associated with the administration of amino acid solutions?
Amino acid solutions are hypertonic and therefore should not be administered alone in the peripheral circulation due tot he damage to veins
What are the energy requirements affected by?
Age, activity, and the severity of disease
How much energy do adults require?
25-35 non-protein kcal/kg/day which is sourced from lipids and glucose due to risk of metabolic problems associated with just using once source
What is the conversion of grams of glucose to calories?
1 grams of anhydrous glucose provides 4kcal
There are different concentrations of glucose available such as 5% w/v
Why should glucose not be used alone as a source of energy?
Risk of hyperglycaemia
Fatty infiltration of liver (as excess glucose
is converted to fatty acids) - ketoacidosis
Excessive CO2 production
Excessive consumption of oxygen
Essential fatty acid deficiency
What do lipid emulsions provide?
Source of energy (dual-energy with glucose) in addition to provision of essential fatty acids
Are lipids energy rich?
Yes 1 gram of oil is equivalent to 10kcal
What are the lipid requirements for patients?
2.5 grams of lipid per kg per day
Monitor renal function
What are some of the lipid preparations that are available?
Source of essential fatty acids
Linoleic acid (52%)
Linolenic acid (8%)
Contains other fatty acids
Oleic acid (22%)
Palmitic acid (13%)
Stearic acid (4)%
Other fatty acids (1%)
What are the most common lipid preparations that are used?
Intralipid 10%, ClinOleic 20%
What are the advantages of using lipid emulsions?
Large amount of energy in small amount of fluid (good for fluid restricted patients)
Allows peripheral administration as they are isotonic and have a venoprotective effect
Contains some fat-soluble vitamins (E and K)
Prevents/reverses essential fatty acid deficiency
What are the two different types of micronutrients?
Trace elements
Vitamins
What are the roles of micronutrients?
Have a role in intermediate metabolism as co-enzymes and co-factors and therefore different levels of micronutrients can affect both enzyme activity and total metabolism.
How often should micronutrients be included in PN administration?
All micronutrients should be added to the daily administration of PN bags
How is the baseline nutritional status calculated?
Acute or chronic illness
Dietary history
Duration and severity of inadequate nutritional intake
What are some of the additional micronutrient losses?
Small bowel fistulae/aspirate – rich in zinc
Biliary fluid loss – rich in copper
Burn fluid loss – rich in zinc, copper, selenium
When is there an additional requirement for micronutrients?
Increased metabolism
Active growth (children)
How can organ function affect micronutrient requirements?
Liver failure – copper & manganese clearance reduced
Renal failure – aluminium, chromium, zinc &
nickel clearance reduced
What are the ten known trace elements?
◼ Iron
◼ Copper
◼ Zinc
◼ Fluorine
◼ Manganese
◼ Iodine
◼ Cobalt
◼ Selenium
◼ Molybdenum
◼ Chromium
What are some brand products for trace elements?
Additrace (provides all trace elements)
Decan
What are some fat soluble vitamins?
◼ A (retinol)
◼ D (ergocalciferol)
◼ E (tocopherol)
◼ K1
What are some water soluble vitamins?
◼ B1 (thiamine)
◼ B2 (riboflavin)
◼ B6 (pyridoxine)
◼ B12
◼ C (ascorbic acid)
◼ Folic acid
◼ Panthothenic acid
◼ Biotin
◼ Niacin
What are some brand products for vitamins?
◼ Vitilipid N Adult – fat-soluble vitamins
◼ Solivito N – water-soluble vitamins
What are examples of electrolytes?
Sodium
Potassium
Calcium
Magnesium
Phosphate
Chloride
Acetate
How can electrolytes requirements be adjusted according to?
Patient’s co-morbidities and blood test results.
Also need to taken into account that some protein and lipid bags also contains electrolytes.
Summarise PN bag contents.
Amino acids (► Nitrogen/protein)
Glucose + Lipids (► Energy + fluid)
Trace elements
Vitamins
Electrolytes
What are the different types of PN bags?
Standard bags (requirements for most adults)
Scratch bags (patient has deviated requirements due to other conditions)
What are the different sites of administration of TPN?
Central administration or PICC lines:
Fluid is too hypertonic to be inserted into a vein (damage it) or poor venous access
Peripheral access
First line as the risk of adverse effects when inserting into a larger blood vessel
What are some of the key pharmaceutical care points regarding peripheral administration?
Need good line care & low tonicity feeds
Patients can be successfully maintained for many weeks on peripheral administration
Can be complicated by phlebitis
Peripheral solutions have an osmolarity of
approximately 800mOsmol/L
What are the indications for peripheral administration?
Duration likely to be short-term
Supplemental feeding
Compromised access to central circulation
No immediate facilities to insert central catheter
High risk of fungal or bacterial sepsis
Contraindication to central venous catherisation
What are the contra-indications to peripheral administration?
Inaccessible peripheral veins
High osmolarity of the PN formulation such as high calorie/nitrogen requirements
When is central administration indicated?
Longer term feeding anticipated
Peripheral route inaccessible
High tonicity formulations required
(Central solutions have an osmolarity of
approximately 2000mOsmol/L
Solution is rapidly diluted into a central vein)
Where is the central administration inserted?
Jugular or subclavian vein
X-ray confirms position of central line
Disadvantages of central administration?
Invasive and costly
How should TPN be administered?
Given at room temperature (removed from the fridge three hours before administration)
Administered under the control of infusion pumps via a giving set
What are the three type of stability problems associated with TPN?
Physical stability
Chemical stability
Microbial stability
What are some of the physical stability issues associated with TPN?
Precipitation
◼ Potential to infuse solid particles – fatal emboli
◼ Prescribed nutrients may not be infused
◼ Cannot be seen if bag contains lipid
Lipid destabilization
◼ Lipid globules may come together & coalesce
◼ Occlude the lung microvasculature – respiratory & circulatory blockages
How is the physical stability issues overcome?
All fluids are passed through a filter before administration to the patient
What are some of the chemical stability issues associated with TPN?
Vitamins present in TPN bags readily undergo chemical degradation on exposure to light especially Vitamin C
How are chemical stability issues associated with TPN overcome?
All bags are protected from light during infusion and storage
Why are microbial stability issues so prevalent?
Due to the highly nutritious environment within the TPN bag
How are microbial stability issues minimised?
Correct manufacturing procedure (lamina flow)
Correct storage
Correct handling
What are some of the questions that should be asked regarding TPN use?
Does the patient need nutritional intervention?
What are their nutritional requirements?
How long will the underlying disease last?
Can the enteral route be used?
What are the routes PN can be administered?
Why is daily monitoring for TPN required?
Evaluate ongoing nutritional requirements, including fluid & electrolytes
Determine the effectiveness of nutritional
intervention
Facilitate early recognition of complications
Identify any deficiency, overload or toxicity to individual nutrients
Determine discrepancies between prescribed, delivered & received dose
What are the monitoring requirements for TPN/fluids?
Clinical symptoms
Temperature
Blood pressure
Fluid balance
Weight, anthropometry
Nitrogen balance
Lipid tolerance
Acid-base profile
Liver function tests
◼ Abnormalities common
Electrolyte profile
Blood glucose
Haematology, CRP
Calcium, albumin
What are some of the complications of TPN?
Line blockage caused by:
Fibrin sheath forming around the line or
thrombus blocking the tip
Internal blockage of lipid, blood clot or salt
& drug precipitates
Line kinking
Blockage of a protective line filter
Line sepsis
Thrombophlebitis
How is refeeding syndrome reduced?
Give half the content- a full bag over 48 hours instead of 24 hours
What is refeeding syndrome?
A metabolic complication occurring when the infused nutrition exceeds the tolerance of a previously malnourished patient
When there is a sudden change from metabolising fat to metabolising carbohydrates (sudden carb load, massive insulin secretion causing metabolic disturbances - potassium and magnesium and phosphate loss, fluid retention)
If at risk of reeding syndrome what should be given?
Thiamine- oral increase
What does NICE guidance say in regards to nutrition?
Consider PN in those who are malnourished or at risk of malnutrition & either have:
◼ inadequate or unsafe oral and/or enteral nutritional intake
◼ a non-functional, inaccessible or perforated (leaking) gastrointestinal tract
Introduce PN progressively & monitor closely
◼ No more then 50% of estimated needs for 1st 24-48 hours
Stop PN when adequate oral and/or enteral support is established