Fluid & Electrolite Management in Surgical Wards

7/31/2019 Fluid & Electrolite Management in Surgical Wards

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Understanding physiology controlling fluidsand electrolytes.

Appreciate difference in surgical patients.

Be able to order fluid regimen for a surgicalpatient.


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The osmolalities (reflecting the osmotic pressure) of theICF and the ECF are similar, although the main cation inthe ECF is sodium, whereas in the ICF it is potassium.

Fluid distribution between the ECF and the ICF is governedonly by changes in the osmotic pressure.

Isotonic fluid (which has the same osmolality as plasma)

administered into the plasma will not enter the ICF, sincethere is no difference in the osmolality.

In ECF, fluid distribution between the plasma and the ISF isonly governed by Starlings forces, i.e. hydrostatic pressure(pushing fluid out of the blood vessels) versus oncoticpressures (sucking fluid back in).

Fluid administered into the plasma would increase thehydrostatic pressure and dilute the oncotic pressure untilthe fluid was evenly distributed throughout the ECF


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Infants have low body fat and 73% or morewater

Total water content declines throughout life

Healthy males are about 60% water; healthy females are around 50%


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2/3 (65%) of TBW is intracellular (ICF)

1/3 extracellular water 25 % interstitial fluid (ISF)

5- 8 % in plasma (IVF intravascular fluid)

1- 2 % in transcellular fluids CSF,intraocular fluids, serous membranes,and in GI, respiratory and urinary tracts(third space)

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Average daily losses in mlsurine 700-1600

intestinal 0-260

sweat 0-150Insensible

lungs/skin 500-900

Fever increases insensible loss by 200cc/day

for each degree (C) or 10% rise in insensibleloss per degree rise in temperature.


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Surgical patients are prone to disruptionnil orally

anesthesia

traumasepsis


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Surgical patients haveMaintenance volume requirements

On going losses

Volume excess/deficitsMaintenance electrolyte requirements

Electrolyte excess/deficits


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This includes:insensible

urinary

stool losse

Body weight Fluid required

0-10Kg 100ml/kg/d

next 10-20kg 50 ml/kg/d

Subsequent 20 Kg 20ml/kg/d15ml/Kg/d for elderly

Remember formula 100 , 50, 20


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Remember formula 4,2,14 x first 10 kg

2 x second 10 kg

1 x each subsequent kg So a 60 kg man will have

4 x10 =40

2 x 10 =20

1 x 40 =40 100ml/hr


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So a 60 kg man will have4 x10 =40

2 x 10 =20

1 x 40 =40100ml/hr


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10 x 100 = 1000 4 x 10 =4010 x 50 = 500 2 x 10 =20

50 x 20 = 1000 1 x 50 = 50

2500 mls / d 110 ml/hr


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fistulaedrains

NG

third space losses Concentration is similar to plasma

Replace with isotonic fluids


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Acute vital signs changes Blood pressure

Heart rate

CVP tissue changes not obvious

urine output low


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Decreased skin turgor Sunken eyes

Oliguria

Orthostatic hypotension High BUN/creatinine ratio

HCT increases 6-8 points per litre deficitPlasma Na may be normal


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NPO deficit = number of hours NPO xmaintenance fluid requirement (ml/hr)

Bowel prep may result in up to 1 L fluid loss.

Superficial surgical trauma: 1-2 ml/kg/hr

Minimal Surgical Trauma: 3-4 ml/kg/hr -head and neck, hernia, knee surgery

Moderate Surgical Trauma: 5-6 ml/kg/hr -

hysterectomy, chest surgery Severe surgical trauma: 8-10 ml/kg/hr (or

more) - nehprectomy


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Goalnormal haemodynamic parameters

normal electrolyte concentration

Methodreplace normal maintenance requirements

Ongoing losses

deficits


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Normal maintenance requirements use BWformula

On going losses

measure all losses in I/O chart

Deficits

estimate using vital signs

operative & third space losses

estimate using HCT


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The best estimate of the volume required isthe patients response


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vital signs Urine output (0.5mls/Kg/hr )

Central venous pressure


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Usually correct over 24 hours For ill patients calculate over shorter period

and reassess e.g. 12 hours or 3 hours forcritically ill cases.

Deficits - correct half the amount over theperiod and reassess


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62 y/o male, 80 kg, for Hemicolectomy NPOafter 2200, surgery at 0800, received bowelprep 3 hr. procedure, 500 cc blood loss

What are his estimated fluid requirements?


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Fluid deficit: 120 ml/hr x 10 hrs = 1200 ml +1000 ml for bowel prep = 2200 ml totaldeficit: (Replace 1/2 first hr, 1/4 2nd hr, 1/43rd hour).

Maintenance: 120 ml/hr x 3hrs = 360mls

Third Space Losses: 6 ml/kg/hr x 3 hrs=1440 mls

Blood Loss: 500ml x 3 = 1500ml Total = 2200+360+1440+1500=5500mls


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The metabolic response to the stresses of surgery involves arise in various hormones, including circulatingcatecholamines, ADH , cortisol and aldosterone.

The overall result of these is the renal conservation of saltand water, with somewhat increased losses of potassium and

hydrogen ions. These effects usually last for about 2448 h.

Despite the high potassium losses in the urine, the serumpotassium is usually maintained or may even transiently rise,through release of cellular contents by damaged tissues.


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Therefore, unless serum potassium levels arevery low, it is probably best to avoid potassiumsupplements in the first day or twopostoperatively.

since water is being retained it is usual to

reduce the fluid replacements to about 2 l inthe first postoperative day, especially inpatients prone to heart failure

Urine output is the best indicator, aiming forgreater than 50 ml/h.

The minimum urine output is about 30 ml/h(60 kg adult) or 0.5 ml/kg/hrs


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A patient who has undergone abdominal surgery islikely to have a transient ileus postoperatively, due tomechanical handling of the bowel or due to anelectrolyte disturbance or even the effects ofanaesthesia.

When an ileus is present, the fluid secreted into thebowel simply lies there, and is not reabsorbedcompletely. These third space losses mean that thepatient effectively has a reduced volume of the ECF,and hence is fluid depleted.

In such patients, extra fluid needs to be given to

allow for the third space losses. Unfortunately, we donot know how much extra fluid

is needed and so must rely on urine output as anindicator.


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There will be sudden diuresis on day 2 or 3postoperatively, explained by recovery of the ileusand reabsorption of the fluids from the bowel.

Similarly, in pancreatitis, patients can lose severallitres of fluids rich in electrolytes and plasma proteinsinto the peritoneal cavity.

Really, the only way to effectively gauge these lossesis by vigorous replacement to maintain their urineoutput and correcting any electrolyte disturbancesaccording to daily U & Es.

If after 2 days 10 l have been put in with only. 3 l of

urine produced, then assuming 12 l of insensiblelosses, this equates to about 5 or 6 l of fluidsequestered into the peritoneal cavity.


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Check i/v regime ordered in op form Assess for deficits by checking I/O chart and

vital signs

Maintenance requirements calculated

Usually K not started

Monitor carefully vital signs and urine output


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Three main types of IVF: Isotonic fluids

Hypotonic fluids

Hypertonic Fluids


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Osmolarity is similar to that of serum. These fluids remain intravascularly

mommentarily, thus expanding the volume. Helpful with patients who are hypotensive or

hypovolemic. Risk of fluid overloading exists. Therefore, be

careful in patients with left ventriculardysfunction, history of CHF or hypertension.

Avoid volume hyperexpansion in patientswith intracranial pathology or spaceoccupying lesions.


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Less osmolarity than serum (meaning: in general lesssodium ion concentration than serum) These fluids DILUTE serum thus decreasing osmolarity. Water moves from the vascular compartment into the

interstitial fluid compartment interstitial fluidbecomes diluted osmolarity descreases water isdrawn into adjacent cells.

These are helpful when cells are dehydrated fromconditions or treatments such as dialysis or diuretics orpatients with DKA (high serum glucose causes fluid tomove out of the cells into the vascular and interstitialcompartments).

Caution with use because sudden fluid shifts from the

intravascular space to cells can cause cardiovascularcollapse and increased ICP in certain patients.


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These have a higher osmolarity than serum. These fluids pull fluid and sometimes

electrolytes from the intracellular/interstitialcompartments into the intravascular

compartments.

Useful for stabilizing blood pressure,increasing urine output, correcting hypotonichyponatremia and decreasing edema.

These can be dangerous in the setting of celldehydration.


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Crystalloids Colloids


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Clear solutions fluids- made up of water &electrolyte solutions; small molecules. These fluids are good for volume expansion. However, both water & electrolytes will cross a

semi-permeable membrane into the interstitialspace and achieve equilibrium in 2-3 hours.

Remember: 3mL of isotonic crystalloid solutionare needed to replace 1mL of patient blood.

This is because approximately 2/3rds of thesolution will leave the vascular space in approx. 1hour.

In the management of hemorrhage, initialreplacement should not exceed 3L before youstart using whole blood because of risk ofedema, especially pulmonary edema.


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Some of the advantages of crystalloids arethat they are inexpensive, easy to store withlong shelf life, readily available with a verylow incidence of adverse reactions, and there

are a variety of formulations that are availablethat are effective for use as replacementfluids or maintenance fluids.

A major disadvantage is that it takesapproximately 2-3 x volume of a crystalloidto cause the same intravascular expansion asa single volume of colloid.


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Colloids are macormolecular substance do notreadily cross semi-permeable membranes or formsediments.

Because of their high osmolarities, these areimportant in capillary fluid dynamics because theyare the only constituents which are effective at

exerting an osmotic force across the wall of thecapillaries. These work well in reducing edema because they

draw fluid from the interstitial and intracellularcompartments into the vascular compartments.

Initially these fluids stay almost entirely in the

intravascular space for a prolonged period of timecompared to crystalloids. These will leak out of the intravascular space when

the capillary permeability is deranged or leaky.


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The general problems with colloid solutions are:

Much higher cost than crystalloid solutions

Small but significant incidence of adverse

reactions Because of gelatinous properties, these can cause

platelet dysfunction and interfere withfibrinolysis and coagulation factors thus possiblycausing coagulopathy in large volumes.

These fluids can cause dramatic fluid shifts whichcan be dangerous if they are not administered ina controlled setting.


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Principal fluid used for IV resuscitation andreplacement of salt loss .

Contains: Na+ 154 mmol/l, K+ - Nil, Cl- - 154mmol/l; But K+ is often added

Isoosmolar compared to normal plasma

Distribution: Stays almost entirely in theExtracellular space

Ofone liter approx 750ml stays Extracellular

fluid; 250ml moves Intravascular fluid So for 100ml blood loss need to give 300-400ml

NS[only -1/3 remains intravascular


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Primarily used to maintain water balance inpatients who are not able to take anything bymouth; Commonly used post-operatively inconjuction with salt retaining fluids ie saline.

Often prescribed as 2L D5W: 1L N.Saline[Physiological replacement of water and Na+losses]

Provides some calories [ approximately 10% ofdaily requirements]

Regarded as electrolyte free contains NOSodium, Potassium, Chloride or Calcium


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Distribution: 66%intracellular

When infused, is rapidly redistributed into theintracellular space; Less than 10% stays in the

intravascular space therefore it is of limiteduse in fluid resuscitation. For every 100ml blood loss need 1000ml

dextrose replacement [10% retained in

intravascular space Common cause of iatrogenic hyponatraemia

in surgical patient


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Similar indications to 5% dextrose; ProvidesNa+ 30mmol/l and Cl- 30mmol/l Ie a

sprinkling of salt and sugar! Primarily used to replace water losses post-

operatively

Limited indications outside of post-operative

replacement Neither really saline ordextrose; Advantage doesnt commonlycause water or salt overload


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What is your goal for therapy?Maintenance

Rehydration

Volume resuscitation

Any baseline electrolyte abnormalities?

ALWAYS look at basic chemistry prior toordering fluids.

Where is the fluid going to go?


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How much volume expansion per liter offluid.

Free water is distributed evenly throughoutthe TBW compartment

Essentially 100% of sodium if confined to theextracellular space

Normal saline contains essentially no freewater.


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2/3 to intracellular space = 660cc

1/3 to extracellular space = 330cc

2/3 to interstitial space =220cc

1/3 to intravascular space =110cc

110/1000 = 11 %


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Essentially all confined to extracellular

compartment

2/3 to interstitial space = 660 cc

1/3 to intravascular space = 340 cc

Approximately 33 %


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Na 1 - 2 mEq/Kg/d K 0.5 - 1 mEq/Kg/d

Usually no K given until after urine output isadequate.

Always give K with care, in an infusion slowly- never bolus

Ca, PO4, Mg not required for short term


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Sodium

(mmole/l)

131 150 30

chloride 111 150 30

potassium 5 nil nil

bicarbonate 29 nil nil

calcium 2 nil nil


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Whenever possible the enteral route shouldbe used for fluids.

These guidelines only apply to children whocannot receive enteral fluids.

These guidelines apply to children beyondthe newborn period.

incorrectly prescribed or administered fluids

are potentially very dangerous.


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The recommended fluid to be infused asmaintenance for well children with normalhydration is:

0.45% NaCl with 2.5% dextros.

Do not use this solution:

If the serum sodium is low

For volume resuscitation

For replacement of fluid deficit indehydrated children

For initial treatment of children withacute neurological conditions (e.g. meningitis)


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How much fluid? Firstly administer an Initial bolus of fluid to

correct hypovolaemia if so, (10-20ml/kg)0.9%Nacl.

Do not use this amount in any subsequentcalculations.

Then Maintenance plus Deficit plus Ongoing

losses


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All children on IV fluids should be weighed priorto the commencement of therapy, 6 - 8 hoursafter the infusion is commenced, and then atleast daily.

All children on IV fluids should have serum

electrolytes and glucose checked beforecommencing the infusion (typically when the IV isplaced) and again within 24 hours if IV therapy isto continue.

For sick children, check the electrolytes and

glucose 4-6 hours after commencing, and thenaccording to results and the clinical situation butat least daily.


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Normal Plasma K+ level 3.5 - 5mmol/L Normal plasma Na+ level 135-145mmol/L


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Low levels of potassium in post-operative patients are

common but hypokalaemia is rarely so severe as toproduce muscle weakness, ileus or arrhythmias. Patients with large and continuous fluid loss from thegastrointestinal tract are prone to develop

hypokalaemia. If potassium supplements are required they may begiven either orally or intravenously.If by the latter route, the rate of infusion should notexceed 10mmol/h. Faster rates may precipitate arrhythmias and shouldonly be undertaken on a unit where the patient can bemonitored for any ECG changes


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Decrease 1 meq/L means deficient 200~400meq K

Check the Osmolarity and Acid-base status,especially DKA and acidosis will mask the K

deficient condition Dont use sugar content IVF Cl

Every bottle< 20 meq KCl, except femoral

line is available


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Estimate the deficit For every 100 mEq below normal, serum K+ usually

drops by 0.3 mEq/L

Highly variable from patient to patient, however!!


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Choose route to replace K+ In nearly all situations, ORAL replacement is

PREFERRED over IV replacement Oral is quicker

Oral has less side effects (IV burns!)

Oral is less dangerous Choose IV therapy ONLY in patients who are npo or

who have severe depletion low serum magnesium often accompanies

hypokalaemia and needs to be corrected to enablerecovery of serum potassiumn)


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Choose K+

prep IV therapy

Adjunct to maintenance fluids (10-20 meq/l)

IV rider/piggyback Generally 40-60 mEq

KCl is PREFERRED AGENT again Avoid dextrose solution (trigger insulin, shift K+)


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Choose dose/timing Mild/moderate hypokalemia

3.0 to 3.5 mEq/L

60-80 mEq PO (or IV) QDay divided doses Sometimes will require up to 160 mEq per day

(refeeders, lots of diarrhea, IV diuretics)

Avoid too much PO at once

GI upset or just poor response

Usually divide as BID or TID dosing


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Choose dose/timing Severe hypokalemia (< 3.0 mEq/L)

Can use combination of IV and PO, again with POpreferred if at all possible

Avoid more than 60-80 mEq PO in a single dose Avoid IV infusion rates faster than 20 mEq/hourcan

cause arrhythmia!!!

Most protocols wont allow more than 10 mEq/hour rateson the floors (ICUs too?)


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S.K

(mEq/L)

3.5 3 2


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Give in a normal saline infusion, as dextrosemay exacerbate the hypoglycaemia byprovoking insulin production.

The rate via a peripheral line should not

exceed 10 mmol/hour to avoid discomfortand phlebitis. Careful monitoring is required both of clinical

condition and bloods (1-3 hourly).

Once ECG abnormalities, muscle weakness orparalysis are resolving, slow the rate ofreplacement or switch to oral replacement.


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Monitor IV K ECG & S.K levels Never give IV push

Never add KCl to Iso M


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Clinical featureAsymptomatic

Generalised fatigue

Paralysis

Palpitations


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Mild Hyperkalemia(5.5-6.5mmol/L)-Tall peaked Twaves with narrow base

Moderate hyperkalemia(6.5-8 mmol/L)-Peaked Twaves

Prolonged PR interval

Decreased amplitude of P wavesWidening of QRS complex

Severe Hyperkalemia-

Absence of P waves

Intraventricular blocks,BBB,Progressive widening of QRS complex

Sine wave pattern ventricular fibrillation,asystole


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The severity of Hyperkalemia is determined bySymptoms

Plasma K+ concentration

Electrocardiographic abnormalities


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Continuous cardiac monitoring and serialelectrocardiograms are warranted in patients withhyperkalemia on rapidly acting therapies.

The serum potassium should be measured at one

to two hours after the initiation of therapy.


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Identify and treat cause 10 20 mL intravenous 10% calcium chloride over

10 min in patients with ECG abnormalities(reduced risk of ventricular fibrillation)

50 mL 50%dextrose plus 10 units short acting

insulin over 2-3min Monitor plasma glucose and K+ over next30-60min)

Regular Salbutomol nebulizers Consider oral or rectal calcium Resonium (ion

exchange resin),although this is more effective fornon-acute hyperkalaemia. Haemodialysis for persistent hyperkalemia


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Defined as sodium concentration < 135mEq/L

Generally considered a disorder of water asopposed to disorder of salt

Results from increased water retention Normal physiologic measures allow a person

to excrete up to 10 liters of water per daywhich protects against hyponatremia

Thus, in most cases, some impairment ofrenal excretion of water is present


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Hyponatremia can be asymptomatic andfound by routine lab testing

It may present with mild symptoms such as

nausea and malaise (earliest) or headache andlethargy

Or it may present with more severesymptoms such as seizures, coma orrespiratory arrest


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If severe symptoms are present, hypertonicsaline needs to be administered to preventfurther decline

If severe symptoms are not present, can start

by initiating fluid restriction and determiningcause of hyponatremia Oral fluid restriction is good first step as it

will prevent further drop in sodium

NOTE: This does not mean that you cant giveisotonic fluids to someone who is trulyvolume depleted


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Patients with serum sodium above 120 aregenerally asymptomatic

Symptoms tend to occur at serum sodiumlevels lower than 120 or when a rapid decline

in sodium levels occur Patients can have mild symptoms at sodium

concentrations of 110-115 mEq/L when thislevel is reached gradually


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As stated earlier, symptoms dictate treatment If severe symptoms are present, starting

bolus of 100 ml of 3% hypertonic saline whichgenerally raise serum sodium level by 2-3

mEq/L Goals for correction:

1.5 to 2 mEq/L per hour for first 3-4 hours untilsymptoms resolve

Increase by no more than 10 mEq/L in first 24 hrs Increase by no more than 18 mEq/L in first 48 hrs


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Oral fluid restriction is the first step No more than 1500 mL per day

If volume depletion is present, isotonic (0.9%)saline can be given intravenously

Careful monitoring should be used whethersymptoms are present or not Serum sodium levels should be drawn every 4-6

hours or more frequently if hypertonic saline isused


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Sodium deficit = Total body water x (desiredNa actual Na)

Total body water is estimated as lean bodyweight x 0.5 for women or 0.6 for men


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60 kg woman with sodium level of 116 How much sodium will bring him up to 124 in

the next 24 hours?

Sodium needed = 0.5 x 60 x (124-116) =

240 Hypertonic saline contains 500 mEq/L of

sodium

Normal saline contains 150 mEq/L of sodium


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The patient needs 240 mEq in next 24 hours That averages to 10 mEq per hour or 20 mL

of hypertonic saline per hour

However, this will only raise the serum

sodium by 0.33 per hour therefore,increasing the rate 60 mL to 90 mL willproduce the desired rate of serum sodiumincrease of 1.0 to 1.5 mEq per hour until

symptoms resolve


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The dreaded complication of increasingsodium too fast is Central PontineMyelinolysis which is a form of osmoticdemyelination

Symptoms generally occur 2-6 days afterelevation of sodium and usually eitherirreversible or only partially reversible

Symptoms include: dysarthria, dysphagia,

paraparesis, quadriparesis, lethargy, coma oreven seizures


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Rate of correction over 24 hours moreimportant than rate of correction in any oneparticular hour

More common if sodium increases by more

than 20 mEq/L in 24 hours Very uncommon if sodium increases by 12

mEq/L or less in 24 hours

CT but preferably MRI to diagnosedemyelination if suspected, though imagingstudies may not be positive for up to 4 weeksafter initial correction


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CPM is associated with poor prognosis

Prevention is key

Small studies have shown thatplasmapharesis done immediately afterdiagnosis may improve clinical outcomes


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Produced by either administration ofhypertonic fluids or much more frequently,loss of thirst

Because of extremely efficient regulatory

mechanisms such as ADH and thirst,hypernatremia generally occurs only inpeople with prolonged lack of thirstmechanism

Patients with loss of ADH (Diabetes Insipidus)usually can compensate with increased fluidintake


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Same labs as workup for hyponatremia:Serum osmolality, urine osmolality and urinesodium

Urine sodium should be lower than 25 mEq/L

if and water and volume loss are cause. Itcan be greater than 100 mEq/L whenhypertonic solutions are infused or ingested

If urine osmolality is lower than serumosmolality then DI is present Administration of DDAVP will differentiate

Urine osmolality will increase in central DI, noresponse in nephrogenic DI


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First, calculate water deficit Water deficit = CBW x ((plasma Na/desired Na

level)-1)

CBW = current body water assumed to be

50% of body weight in men and 40% inwomen

So lets do a sample calculation: 60 kg woman with 168 mEq/L

How much water will it take to reduce her sodiumto 140 mEq/L


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Water deficit = 0.4 x 60 ([168/140]-1) = 4.8L But how fast should I correct it? Same as hyponatremia, sodium should not be

lowered by more than 12 mEq/L in 24 hours Overcorrection can lead to cerebral edema which

can lead to encephalopathy, seizures or death

So what does that mean for our patient? The 4.8 L which will lower the sodium level by 28

should be given over 56-60 hours, or at a rate of75-80 mL/hr

Typical fluids given in form of D5 water


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Loss of thirst usually has to occur to producehypernatremia

Rate of correction same as hyponatremia

D5 water infusion is typically used to lower

sodium level Same diagnostic labs used: Serum osmolality,

Urine osmolality and Urine sodium

Beware of overcorrection as cerebral edemamay develop


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Patients who are malnourished are prone to manycomplications, such as delayed wound healing, muscleweakness and an increased tendency to infection. There isevidence that patients with poor nourishment prior to surgerywill benefit from preoperative supplementation and do betterafter their operation.

There are a lot of reasons why hospital patients becomemalnourished. They may have a decreased appetite due to theillness itself. They may have increased nutritional demands ortheir digestion may be impaired.

Another reason could be due to the hospital stay itself, i.e.dislike of hospital food, being rushed off for an X-ray orultrasound at noon, or being nil by mouth.


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If oral intake is not anticipated within 710days of surgery, then nutritional support isindicated (perhaps 5 days in a previouslymalnourished patient).

The main indication for preoperativenutritional support is severe malnourishment(greater than 10% weight loss).

Nutritional support can vary from meresupplementation of vitamins,or protein in ahigh-protein diet, to a complete replacementof all essential foodstuffs.


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Enteral diets are those given via the gut,including oral intake. The ideal situation is one where the patient takes

in all the required nutrition orally. If this is not possible, then enteral feeding is the

next option. This involves passing the food into the gut,allowing it to be absorbed normally, eitherthrough a nasogastric tube or, if required forlonger periods, via a gastrostomy or jejenostomy.

The commonest indication for enteral feeding iswhere there is a problem with swallowing, causedby a stroke or oesophageal obstruction


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Parenteral nutrition bypasses the gut and involves a

specialised feed directly into the patients bloodstream. Parenteral nutrition may be used as a supplement to

enteral feeding when it is usually given through a cannulain a peripheral vein.

Alternatively, total parenteral nutrition (TPN) can be usedto deliver the complete nutritional requirements. As TPN has a high osmolality it is toxic to veins and is

usually given via a central line. Unfortunately, parenteral feeding has some

complications, including an increased risk of infection, due

to CVP line


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Another complications are villous atrophy in the gut. This makes the gut wall more permeable to bacterial

flora and increases the risk of translocation ofbacteria into the bloodstream.

Electrolyte imbalances are likely and, therefore, theurea and electrolytes should be checked daily and

adjusted accordingly. Hyperglycaemia is another problem and the patient

may need to be given insulin temporarily while onTPN.

Other disturbances of liver function are common

(possibly because of fatty infiltration of the liver) anda cholestatic picture may be seen with raised alkalinephosphatase,and hence LFTs should be measuredevery few days.


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Documents

Fluid & Electrolite Management in Surgical Wards