Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

ANESTHESIA PRACTICE 2 > FLUID MANAGEMENT AND ADMINISTRATION > Flashcards

FLUID MANAGEMENT AND ADMINISTRATION Flashcards

1
Q

how much total body water is there in an a 70kg adult?

A

60% water (600ml/kg) = 42L in 70kg pt

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

how much total body water is intracellular vs extracellular?

A

2/3 of total body water is intracellular = 28L
1/3 of total body water is extracellular = 14L
OR 2:1 extra- to intra-cellular ratio

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

roughly how much of extracellular fluid is in plasma? in interstitial fluid?

A

plasma = 2.5L
interstitial fluid = 9L
OR roughly 1:4 plasma to interstitial fluid ratio

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what is the ratio of plasma to blood volume?

A

1:2
plasma = 2.5L
total blood volume = 4-5L

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

describe the filtration system in capillaries in terms of hydrostatic and oncotic (colloid osmotic) pressures

A

net pressure = hydrostatic pressure – colloid osmotic pressure

  • hydrostatic pressure (Pcap) forces fluid out of the capillary
  • colloid osmotic pressure (π) of proteins within the capillary pulls fluid into the capillary
  • as long as Pcap > π, net filtration out of the capillary occurs. when π > Pcap, net absorption occurs.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what is the net flow of fluid out of the capillaries per day?

A

net flow out = 2L/day

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

from what compartments are oncotic and hydrostatic pressures generated?

A

blood and interstitial fluid both contribute to hydrostatic and oncotic pressures, but inversely affect filtration.
* blood hydrostatic pressure induces filtration, while interstitial hydrostatic pressure induces absorption

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what is the potential impact of preoperative fasting to perioperative fluid balance?

A

continued insensible and urinary losses causing hypovolemia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

how long should children remain NPO before surgery?

A

3-4hr

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what is the potential impact of vasodilation from general/regional anesthestic to perioperative fluid balance?

A

venodilation causing decreased preload

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what is the potential impact of insensible losses from intraoperative surgical exposure to perioperative fluid balance?

A

hypovolemia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what is the potential impact of fluid shift from surgical trauma and inflammation to perioperative fluid balance?

A

can lead to third space fluid accumulation and/or increased interstitial fluid volume

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what is the potential impact of blood loss to perioperative fluid balance?

A

reduced blood volume, decreased interstitial volume

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what is the goal of perioperative fluid management?

A

to provide appropriate amount of parenteral fluid to maintain 1) intravascular volume and cardiac preload, 2) oxygen-carrying capacity, 3) coagulation status, 4) acid-base homeostasis, and 4) electrolyte balance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what is the basic approach to fluid management?

A

MDLEANS*

  • provide MAINTENANCE fluid (type and rate)
  • replace fluid DEFICITS
  • monitor and replacing ongoing LOSSES
  • consider ELECTROLYTES
  • consider ACID-BASE status
  • NUTRITIONAL needs
  • SPECIAL patient or procedure considerations
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

how do the Na and Cl concentrations and pH of 0.9% NaCl compare to plasma?

A

plasma – Na: 140 Cl: 103 pH: 7.4
0.9% NaCl – Na: 154 Cl: 154 pH: 5.7
if given over long periods of time, will cause the plasma to become acidic => metabolic acidosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

how do the Na and Cl concentrations and pH of LR compare to plasma?

A

plasma – Na: 140 Cl: 103 pH: 7.4

LR – Na: 130 Cl: 109 pH: 6.4

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

why is LR the more preferred fluid for fluid management?

A
  1. NaCl concentrations closer to that of plasma
  2. LR is the only fluid with Ca (3 vs. 5 in plasma)
  3. contains lactate as a buffer; turned to bicarbonate in the liver, which is the natural buffer in plasma
  4. pH of lactated ringers closer to that of plasma; will not induce metabolic acidosis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what are the pros and cons of using plasmalyte or normosol

A

most physiologic; can mix with blood products (no Ca++)

>2x cost of LR or NS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what are the pros and cons of using LR?

A

closer to physiologic than NS (good choice for most patients), but because it contains Ca++, cannot be mixed with blood products
cannot be used in patients with serious lactic acidosis or live impairment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what are the pros and cons of using NS 0.9%?

A

good for neurosurgery/ICP, blood products, hypercalcemia, hypochloremia, hyponatremia; keep fluid normovolemic outside of vessels – prevents edema with fluid
high Na and Cl – at large volumes can cause acidosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what is the best fluid to administer for cerebral edema?

A

hypertonic solutions – hypertonic saline (3%-23%)

* must use central line and pump

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

what are two ways to estimate maintenance rate?

A

2ml/kg/hr (acceptable for adults)

4:2:1 rule (use for pediatrics)

24
Q

describe the 4:2:1 rule for maintenance fluid rate?

A

4ml/kg/hr for the FIRST 10kg
+ 2ml/kg/hr for the SECOND 10kg
+ 1ml/kg/hr for EACH ADDITIONAL kg

25
Q

what are the two major sources of fluid deficit?

A
  1. fasting, prolonged NPO

2. other preoperative losses (bleeding, emesis, diarrhea, bowel prep

26
Q

define blood loss in terms of hemorrhage class I-IV as well as CV response

A
  • class I – 40% (>2L) blood loss – critical HR and BP
27
Q

how is fasting fluid deficit estimated?

A

multiply maintenance fluid rate x NPO time

28
Q

how is bowel prep fluid deficit estimated

A

500-1500ml

29
Q

what is the typical approach for correcting fluid deficit?

A

correct 50% in first hour; correct remaining 50% over next two hours (3hr total)

30
Q

which fluid type is more effective in replacing intravascular losses?

A

colloids

31
Q

which fluid type increases the risk of tissue edema, airway edema and bowel edema?

A

crystalloids – requires more total fluid correct deficits

32
Q

what is the rational approach to determining the fluid type for correcting fluid deficit?

A
  • replace total body deficits with crystalloid

* replace intravascular deficits with colloid

33
Q

how much blood does a fully soaked 4” surgical sponge hold? a fully soaked 12” gauze laparotomy tape?

A

4” surgical sponge = 10ml

12” gauze laparotomy tape = 100-150ml

34
Q

what is the replacement ratio of crystalloid:blood loss? colloid:blood loss? blood products:blood loss?

A

crystalloid – 3:1
colloid – 1:1
blood products –1:1

35
Q

what is the protocol for administering blood products for blood loss replacement?

A
  • PRBC when transfusion threshold reached
  • FFP if giving ≥ 4u PRBC (plus labs)
  • platelets if giving ≥ 6u PRBC (plus labs)
  • cryoprecipitate based on coats (fibrinogen
36
Q

what is meant by third-spacing?

A

fluids shifting from intravascular space to interstitial space, causing edema

37
Q

how much replacement is typically necessary for evaporation/insensible losses?

A
  1. 5-1ml/kg/hr

* increases with increasing temperature

38
Q

define ascites

A

accumulation of fluid in the peritoneal cavity, causing abdominal swelling

39
Q

how is ascites fluid loss managed?

A

replace with 25% albumin; 5-8g/L over 5L

40
Q

how is excessive urine output (i.e., inadvertent mannitol administration) managed?

A

monitor for hypovolemia; replace as needed.

41
Q

what are the three primary ways of diagnosing hypovolemia?

A

BP, HR, CVP
labs
UOP
PPV, SPV, delta down, SVV

42
Q

how are CVP and blood volume related?

A

there is no association between CVP and circulating blood volume; CVP does not predict fluid responsiveness across a wide spectrum of clinical conditions

43
Q

what lab values are useful in diagnosing hypovolemia?

A

lactate, base deficit, hematocrit

44
Q

below what UOP can you reasonably assume hypovolemia?

A
45
Q

what are the requirements for using PPV and SPV for diagnosing hypovolemia?

A
  1. arterial line
  2. no sustained arrhythmia
  3. controlled mechanical ventilation
  4. 8ml/kg tidal volume
46
Q

how is PPV interpreted in terms of diagnosing hypovolemia?

A

PPV > 10 or > 12% indicates fluid responsiveness

*

47
Q

how is SPV interpreted in terms of diagnosing hypovolemia?

A

SPV > 7.5 or ? 10 indicates fluid responsiveness

48
Q

what types of cases require fluid restriction approach?

A
  • liver resection (low CVP) – keep dry until resection is complete
  • intrathoracic surgery – keep lungs dry
  • renal failure/dialysis, heart failure – avoid fluid overload
49
Q

what types of cases require liberal fluid approach?

A
  • kindey transplant (donor and recipient) – typically 3L crystalloid
  • outpatient same day surgery (20/30ml/kg)
50
Q

what is meant by “goal directed” fluid therapy?

A

use of a monitor to guide fluid administration

51
Q

how is fluid responsiveness assessed by stroke volume measurements?

A
  • fluid responsive if fluid bolus leads to > 10% increase SV
  • not fluid responsive if fluid bolus does not lead to > 10% increase SV
    • the increase in stroke volume decreases as fluid status is optimized
    • cardiac output will fall with severe fluid overload
52
Q

what is the fluid challenge for EDM fluid optimization protocol?

A

250mll 5% albumin over 5min

53
Q

how is fluid responsiveness predicted by pulse pressure variation?

A
  • PPV ≥ 13% predicts fluid responsiveness
  • PPV 8-12% is indeterminate (some pts fluid responsive)
  • PPV
54
Q

what is the fluid challenge for PPV fluid optimization protocol?

A

250ml 5% albumin or 300-500ml LR/PLyte over 5-10min.

55
Q

how should you approach fluid management for pediatrics?

A
  • meticulous attention to detail required
  • less room for error
  • calculate everything to patient’s weight
  • use buretrol to avoid fluid overdose
  • blood products are also dosed based on weight
  • neonates may require dextrose
56
Q

give two criteria for selecting maintenance fluid

A
  1. 0.9% NaCl for neurosurgery patients

2. otherwise, LR or Plasmalyte for most pts

ANESTHESIA PRACTICE 2 (5 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions