This document discusses fluid and electrolyte management in postoperative patients. It begins by explaining how surgery can disrupt normal physiology and fluid balance. It then outlines goals for postoperative fluid therapy and factors to consider when determining fluid needs. Routine intravenous fluid regimens for the first 3 days are presented. The document also addresses specific issues like fluid management in patients with hypertension or diabetes and blood transfusion guidelines.

1. Fluid and
Electrolytes
Management in
Post op patients
Under guidance of Dr.(Prof) Nootan.C.
Presented by Dr.Sonal Dixit

2. Why fluid therapy in surgical pt
needs special consideration ?
• After surgery modification in normal physiology
of fluid and electrolytes balance.
• - ACUTE STRESS leads to increased
sympathetic stimuli- tachycardia,
vasoconstriction & stress.
• Increased ACTH stimulate adrenal gland
which secretes large amount of hydrocortisone
to fight acute stress and aldosterone which leads
to Na retension and urinary loss of K.

3. • Increased ADH secretion causes water
retension , reduction in U.O to as low as
500 ml on 1st post op day.
• NBM status leads to hypovolemia prior to
surgery, pt becomes hypotensive during
surgery & anaesthesia.
• Fluid loss
• Surgical stress or direct damage of
kidney,brain ,lung , skin or GI tract.

4. Goal of fluid therapy
• Aim to maintain
• B.P >100/70 mm of Hg
• Pulse rate of less than 120 bpm
• Hourly U.O between 30 and 50 ml
• Normal temperature, warm skin , normal
respiration and sensorium.

5. When and how long to five post-
op iv fluid ?
• Minor or major surgery?
• Short operative procedure ( no handling of
intestine or viscera ) – maintenance i.v fluid to
correct deficit due to NBM state. After 4-5 hours
oral fluid is restarted & iv fluid is not needed.
• Major surgeries ( handling of intestinal viscera
) – requires post op iv fluid for few days.After
ensuring normal movement of intestine oral fluid
intake is restarted.
• Major surgery ( handling of intestinal viscera
not done ) Most of OBG surgeries – I.V fluid is
required for only 24 to 48 hrs.

6. Which factors to be considered
before writing post op iv fluid ?
• Age , weight , vital data, hydration status and U.O.
• Nature of surgery, blood loss , nature and vol of fluid
and blood replaced intraoperatively.
• Drain output , fluid lost at operative site.
• Renal status,associated illness ( HT,DM) and
associated electrolytes and acid base disorders, if
any.
• Insensible loss due to atmospheric
temp,pyrexia,hyperventilation etc.

7. Routine Post Op Fluid for 1st 3
days?
• 1st 24 hrs of surgery- 2 lits D-5 or 1.5 lits
D-5 + 500 ml isotonic saline.
• 2ND post Op day- 2 lit 5% dextrose+ 1 lit of
0.9% saline.
• 3rd post op day – Similar fluid + 40-60 mEq
k per day.
• Guidelines which may require modification
depending upon clinical situation.

8. Why maintenance I.V fluid on the 1st post op
day has less salt and its total volume is lesser?
Increased ADH and aldosterone secretion –
salt and fluid retention by the kidney .
So as to avoid overloading of either salt or
water , i.v fluid with lesser or even no
sodium and in lesser volume than routine
maintenance need of normal individual is
prescribed.

9. When on 1st post op day ,saline
containing fluid is preferred?
• Elderly patients with salt losing
nephropathy.
• Head injury or neurosurgical pts.
• Patients on diuretics and mannitol.
• To replace nasogastric aspiration and
drain output.
• In most of the major surgery, saline is
given to replace third space losses.

10. K is avoided in I.V fluids for 1st 2
post operative day?
• Pt may have oliguria or azotemia.
• Post op trauma release K from intracellular
to extracellular compartment-
hyperkalemia.
• Intra or post op transfusion of stored blood
• Post operative metabolic acidosis shifts
intracellular K extracellularly.

11. How to infuse IV fluid
postoperatively ?
• Maintenance fluid should be given at a
steady rate over an 18 to 24 hrs period.
• If given over a short period ,renal excretion
of excess salt and water may occur. But as
the normal losses continues over 24 hrs,
body will be deprived of their fluid need
during the remaining period.

12. Volume Excess
• Blood excess – pulmonary congestion.
• Saline excess- weight gain, periorbital
puffiness, hoarseness or dysnoea on
exertion.
• Hypotonic fluid excess ( 5% dextrose) –
hyponatremia ( mental confusion,
drowsiness or rarely coma or convulsions).

13. Fluid volume deficit
• Decreased U.O < 30 ml/hr
• Postural hypotension
• Tachycardia
• Diminished skin turgor
• Decreased capillary refill time
• Inc BUN out of proportion to creatinine
TREATMENT
Depends on the type of fluid lost , can be done
with isotonic solutions –NS or LR.

14. Hyponatremia
• Excess ADH- retension of water In excess of sodium.
• Excess 5% dextrose
• Water administration consistently which exceeds water
loss.
• Nausea without vomiting, drowsy, weak, confused or
gets convulsion.
TREATMENT
Avoid using hypotonic solution.
Avoid excessive use of electrolyte free solutions during
the first 2-4 post op days.
Serum Na should be kept between 130-135 mEq/ml

15. Hypernatremia
• Uncommon
• Excess isotonic saline.
• Diabetes insipidus
• Excess pure water loss in severe
hyperglycemia due to osmotic diuresis.
Treatment
0.45% NaCl – half strength saline

16. Hypokalemia
• Most common
• Lost through urine or GI.
• Post op infusion of mannitol or diuretics.
• Prolonged administration of potassium free i.v fluids.
• Extreme weakness , muscular hypotonia , paralytic
ileus. Pts on digitalis therapy are more prone to
develop cardiac arrythmias due to hypokalemia.
Treatment
Daily supplement 60 -100 mEq QD.
Remember –hyperkalemia is more dangerous than
hypokalemia.

17. Hyperkalemia
• Uncommon
• Cardiovascular symptoms- bradyarrhythmias,
hypotension , diastolic cardiac arrest.
• ECG changes – wide QRS complex, peaked
T waves.
• Treatment
• Inj cal gluconate , inj sod bicarbonate,
glucose and insulin , kayexalate ( orally or by
retension enema ).

18. Fluid management in
Hypertension
• Remember that fluid overload can easily lead to
pulmonary edema and cardiac failure in
hypertensive patient, so ensure that fluid should
be administered over strict 24 hrs and not faster.
• Sodium containing fluids will cause water
retension and will increase the B.P eventually.
• Strict B.P monitoring should be done on 1st post
op day.
• Lasix will drop the b.p , increase the urine output
but can cause disturbance in electrolyte levels.

19. Fluid management in Diabetes
• In diabetic post op patients there are high chances
of development of diabetic ketoacidosis.
• Avoid using dextrose on 1st post op day as already
due to excess glucocorticoids the level of glucose
is on the higher side.
• With DNS insulin should be added i.e neutralizing
drip should be prepared. 10 units of human
actrapid in 1 lit of DNS is a good option . RBS
charting should be done 2 hrly of 1st day , 4 hrly on
2nd – come back to subcutaneous insulin or oral
hypogycemic drugs once the patient starts on oral.

20. What is Sliding Scale?
• RBS hourly.
• 150 to 200 – 4 units
• 201 to 250 – 6 units
• 251 to 300 – 8 units
• And so on …
I.U of human insulin or human actrapid .

21. Blood transfusion
Life saving

22. Advantage
• Most physiological way to replace blood
loss.
• Corrects hypotension secondary to blood
loss.
• Adequate tissue oxygen.
• Effective than crystalloids and cheaper
than colloids to correct hypotension.

23. How to estimate intra op blood
loss?
• Weigh sponges before and after use- diff
in grams is eqivalent to ml of blood
absorbed.
+
. Blood in suction bottle
* 1½
= approx blood loss.

24. How to decide need for B.T?
• Pre op hemoglobin or hematocrit – Oxygen
carrying capacity is unaffected till Hb is as
low as 8 gm/dl & hematocrit is 25%.
• Percentage of blood loss
Total blood vol in adult female is 65 ml/kg.
Loss less than 10% is insignificant.
10%-20%- clinical decision
>20% - 100 % B.T

25. Eg - 500ml loss in 65 kg female ( total blood
vol in ml = 65* 65 = 3575 ml ) ,the loss
less than 10% of total blood volume, which
is not significant loss and does not require
B.T.
But same 500 ml loss in 20 kg female is
30% of total vol- significant and require
B.T.

26. Other factors
• Vital data – emergency surgery in
hypotensive pt needs B.T.
• Hydration status
• Old people
• Pts with IHD

27. How to estimate new Hb after
intra op blood loss?
• Step 1 . Convert vol of blood loss into %
• % reduction of Hb = 1.25 * vol of blood
loss / weight
• Step 2 . Convert % into reduction in gm/dl
• = preop Hb * % of reduction / 100
• Step 3 . Hb status after blood loss
• = pre op hb in gm/dl – reduction in Hb
gm/dl

28. Example – A 50 kg women with
14gm/dl loses 800 ml .
• New hb status?
% reduction of Hb = 1.25 * 800/50 = 20%
Reduction in gm/dl = 20 * 14/100 = 2.8 gm/dl
Hb status after blood loss = 14-2.8 =11.2 gm/dl.

29. When not to give B.T?
• Blood loss less than 500 ml in adult with
normal preop Hb.
• Loss of 10% of estimated blood vol is well
tolerated , such losses are usually
replaced with crystalloids like RL or 0.9%
saline.
• As a rule blood loss needs to be
replaced with 3 times vol of
crystalloids.

30. When to give B.T?
• Blood loss > 20% of blood volume.
• Replacement of blood loss between 10%
and 20% is a matter of clinical discretion. If
Hb status after loss is expected to be less
than 10gm/dl ,B.T is given.
• 500ml to 1000ml – single unit of blood is
req.
• B.T is mandatory if Hb falls below 8gm/dl
after blood loss.

31. What is MABL?
• Maximum allowable blood loss- amount of
blood loss, which does not require B.T.
• = preop pt’s hematocrit-25 * estimated
blood volume / preop pt’s hematocrit.
• Lowest acceptable hematocrit value is
25%.

32. THANK YOU
Treat the patient as a whole,
“Half a sheep is mutton.”