Fluid management in adults involves balancing fluid intake and losses to maintain homeostasis. The body contains total body water (TBW) divided between intracellular fluid (ICF) and extracellular fluid (ECF). Water and electrolyte requirements are met through maintenance fluids which are administered based on weight. Additional fluids must be given to replace deficits from fasting, ongoing losses, blood loss, and third spacing during surgery. Fluid status is monitored for signs of hypo- or hypervolemia, and fluid therapy is adjusted based on the patient's condition and fluid balance. Proper fluid management is critical in the perioperative period to prevent organ hypoperfusion.

1. Fluid Management in Adults
2009/8/19 ⼩小港外科 Intern teaching
R2 ⿈黃昱豪

2. Surgeon’s Maintenance Fluid

3. Human beings are
built by water......

4. ⼥女⼈人是⽔水作的？？
Male (60%) > female (50%)

6. Biomedical Importance of Water
Homeostasis (CES)
Water distribution
PH maintenance
Maintain Electrolyte Concentration
Set of Fluid Balance
Depletion (dehydration)
Intoxication (over-hydration)
Osmotic & non osmotic mechanism

7. Body Fluid Compartments:
2/3
X 50~70%
lean body weight
TBW
3/4
Male (60%) > female (50%)
TBW(Total Body Water)=0.6xBW
ICF:
55%~75%
1/3
ECF
ICF=0.4xBW
ECF=0.2xBW
1/4
Extravascular
àInterstitial
fluid
Intravascular
àplasma

8. Mr.Iron, 60-Kg male, he has......IVW
Ans:
60Kg x 60%(man) x
1/3(ECF) x 1/4(IV) =
3kg intravascular water
(about 3000 ml plasma)

9. Composition of Body Fluids:
Cations
150
Anions
100
50
0
ECF
Na+
ClHCO3Ca 2+
Mg 2+
Protein
50
ICF
K+
PO43Organic
anion
100
150
Osmolarity = solute/(solute+solvent)
Osmolality = solute/solvent (290~310mOsm/L)
Tonicity = effective osmolality
Plasma osmolility = 2 x (Na) + (Glucose/18) + (Urea/2.8)
Plasma tonicity = 2 x (Na) + (Glucose/18)

10. Regulation of Fluids:
Hydrostatic pressure v.s. Oncotic pressure
à Albumin is the major determining oncotic pressure

11. Regulation of Fluids:
Renal sympathetic nerves
Renin-angiotensinaldosterone system
Atrial natriuretic peptide (ANP)

12. Fluid management
output, loss
intake, produce

13. FLUID REQUIREMENTS
Sources
Losses (35ml/kg/day)
Urine
Water
1500 ml
Food
800 ml
Stool
200 ml
Oxidation
300 ml
Skin
500 ml
(0.5~1ml/kg/hr)
(12ml/kg/day)
1500 ml
Resp. Tract
Total
2600 ml
400 ml
Total
2600 ml
Practically Daily Input/Output balance = +500ml

14. Fluid Management
Maintenance
Ongoing loss
Deficit
lMaintenance＋Deficit＋Ongoing loss

15. Maintenance fluid

16. Maintenance Fluid:
Water require, Rule:
100-50-20(60kg=2300ml/day)
100ml/kg/d(for 1st 10kg) ＋50ml/kg/d(for 2nd 10kg)＋20ml/kg/d(per add 1 kg)
4-2-1(60kg=100ml/hr=2400ml/day)
4ml/kg/hr(for 1st 10kg) ＋2ml/kg/hr(for 2nd 10kg)＋1ml/kg/hr(per add 1 kg)
1.5ml/kg/hr(60kg=90ml/hr=2160ml/day)
Electrolytes require:
- Na+: 2-3mmol/kg/day
- K+: 1~2mmol/kg/day
Glucose supplement(if NPO):
100~150g dextrose/per day
"Two stereoisomers (isomeric molecules
whose atomic connectivity is the same but
whose atomic arrangement in space is
different.) of the aldohexose sugars are
known as glucose, only one of which (Dglucose) is biologically active. This form
(D-glucose) is often referred to as dextrose
monohydrate, or, especially in the food
industry, simply dextrose (from
dextrorotatory glucose).

17. Mr.Iron, 60-Kg male, NPO
Maintenance Fluid......
1. Daily Na Requirement＝3meq/kg ×60kg＝180meq
Daily K Requirement=1meq/kg ×60kg＝60meq
2. Maintenance water＝2300ml＝2.3L
3. 【Na】of fluid＝180meq÷2.3L＝
78meq/L≒1/2 normal saline
4. 0.9%NaCl＝154meq/L

18. MAINTENANCE vs. REPLACEMENT
n Maintenance:
• Provide normal daily requirements:
• Water: 2.5 L
• Sodium ½ or ¼ NS
• KCl 40-60 meq
n Example:
D5 ½ NS with KCL 20 meq/L running at 100 ml/hr

20. Intravenous Fluids:
• Crystalloids
• Colloids
• Blood/blood products and blood
substitutes

21. Parenteral Fluid Therapy:
Crystalloids:
- contain Na as the main osmotically
active particle
- useful for volume expansion (mainly
interstitial space)
- for maintenance infusion
- correction of electrolyte abnormality

22. Crystalloids:
Isotonic crystalloids
- Lactated Ringer’s, 0.9% NaCl
- only 25% remain intravascularly
Hypertonic saline solutions
- 3% NaCl
Hypotonic solutions
- D5W, 0.45% NaCl
- less than 10% remain intravascularly, inadequate for fluid
resuscitation

23. Colloid Solutions:
Contain high molecular weight
substancesàdo not readily migrate across
capillary walls
Preparations
- Albumin: 5%, 25%
- Dextran
- Gelofusine
- Voluven

24. Common parenteral fluid therapy-Crystalloid
Solutions
Volumes
Cl-
HCO3-
5
103
27
280-310
3
109
28
273
K+
Ca2+
142
ECF
Na+
4
4
Mg2+
Dextrose
mOsm/L
Lactated
Ringer’s
500
130
0.9% NaCl
500
154
154
308
0.45% NaCl
500
77
77
154
D5W/D10W
D2.5/0.45%
NaCl
50/100
500
3% NaCl
77
513
Taita No.3
500
75 12
Taita No.4
500 110 20
Taita No.5
400
36 18
77
Acetate:20
Phosphate:6
Acetate:16
Phosphate:12
Acetate:28
Phosphate:12
3
25
513
406
1026
26
20
285
102
8
300
17
100
669

25. Common parenteral fluid therapy-Colloid
Solutions
Volumes
K+
Ca2+
142
ECF
Na+
4
5
6%
Hetastarch
500
154
5% Albumin
250,500
130-16
0
25%
Albumin
20,50,100
130-16
0
Mg2+
Cl-
HCO3-
103
27
Dextrose
mOsm/L
280-310
154
310
<2.5
130-16
0
330
<2.5
130-16
0
330

26. The Influence of Colloid & Crystalloid on
Blood Volume:
Blood volume
Infusion
volume
200
1000cc
500cc
500cc
500cc
600
1000
Lactated Ringers
5% Albumin
6% Hetastarch
Whole blood

27. Deficits fluid

28. NPO and other deficits
• NPO deficit =number of hours NPO x
maintenance fluid requirement.
• Bowel prep may result in up to 1 L fluid
loss.

29. Third Space Losses
• Isotonic transfer of ECF from functional body
fluid compartments to non-functional
compartments.
• Depends on location and duration of surgical
procedure, amount of tissue trauma, ambient
temperature, room ventilation.
Department of Anesthesiology
Uniformed Services University of the Health Sciences

30. Replacing Third Space Losses
• 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)
- AAA repair, nehprectomy
Department of Anesthesiology
Uniformed Services University of the Health Sciences

31. Ongoing loss fluid

32. • Measurable fluid losses:
• Foley tube
• Unmeasurable fluid
losses:
• ostomy output
• Fever(Temp of
38.3C~39.4C, >24hr
==>500ml ;>37C,
100~150ml/C)
• PTGBD, T-tube
• Ventilator
• Bleeding
• Bleeding
• NG suctioning/
vomiting
!
!
!

33. Composition of GI Secretions:
Source
Volume (ml/24h)
Na+*
K+
Cl-
HCO3-
Salivary
1500 (500~2000)
10 (2~10)
26 (20~30)
10 (8~18)
30
Stomach
1500 (100~4000)
60 (9~116)
10 (0~32)
130 (8~154)
0
Duodenum
100~2000
140
5
80
0
Ileum
3000
140 (80~150)
5 (2~8)
104 (43~137)
30
Colon
100-9000
60
30
40
0
Pancreas
100-800
140 (113~185)
5 (3~7)
75 (54~95)
115
Bile
50-800
145 (131~164)
5 (3~12)
100 (89~180)
35
* Average concentration: mmol/L

34. Other factors
• Ongoing fluid losses from other sites:
- gastric drainage
- ostomy output
- diarrhea
- PTGBD, T-tube
• Replace volume per volume with crystalloid solutions

35. Blood Loss
• Replace 3 cc of crystalloid solution per cc of blood
loss (crystalloid solutions leave the intravascular
space)
• When using blood products or colloids replace blood
loss volume per volume

36. Example
• Mr.Michelin, 62 y/o male, 80 kg, for hemicolectomy
• NPO after 2200, surgery at 0800, received bowel prep
• 3 hr. procedure, 500 cc blood loss
• What are his estimated intraoperative fluid
requirements?

37. Example (cont.)
• Ans:
• Fluid deficit: 1.5 ml/kg/hr x 10 hrs = 1200 ml + 1000
ml for bowel prep = 2200 ml
• Maintenance: 1.5 ml/kg/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

38. Monitor

39. Hypovolemia

40. Signs of Hypovolemia:
Diminished skin turgor
Dry oral mucus membrane
Oliguria
- <500ml/day
- normal: 0.5~1ml/kg/hr
Tachycardia
Orthostatic hypotension/Hypotension
Hypoperfusionàcyanosis
Altered mental status

41. Orthostatic Hypotension
• Systolic blood pressure decrease of greater than
20mmHg from supine to standing
• Indicates fluid deficit of 6-8% body weight
- Heart rate should increase as a compensatory
measure
- If no increase in heart rate, may indicate
autonomic dysfunction or antihypertensive drug
therapy

42. Clinical Diagnosis of Hypovolemia:
Thorough history taking: poor intake, GI
bleeding…etc
BUN : Creatinine > 20 : 1
- BUN↑: hyperalimentation, glucocorticoid
therapy, UGI bleeding
Increased specific gravity
Increased hematocrit
Electrolytes imbalance
Acid-base disorder

43. Hypervolemia

44. Signs of Hypervolemia:
Hypertension
Polyuria
Peripheral edema
Wet lung
Jugular vein engorgement
Especially when
hypo-albuminemia

45. Management of Hypervolemia:
Prevention is the best way
Guide fluid therapy with CVP level or
pulmonary wedge pressure
Diuretics
Increase oncotic pressure: FFP or
albumin infusion (may followed by diuretics)
Dialysis

47. Summary
• Fluid therapy is critically important during the
perioperative period.
• The most important goal is to maintain hemodynamic
stability and protect vital organs from hypoperfusion
(heart, liver, brain, kidneys).
• All sources of fluid losses must be accounted for.
• Good fluid management goes a long way toward
preventing problems.

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