IV Fluids (Final) Flashcards
1
Q
Fluid compartments
A
- Intracellular
- Extracellular
- Intravascular
- Interstitial
2
Q
Total body water volume
A
- 40L
- 60% body weight
3
Q
Intracellular fluid volume
A
- 25L
- 40% body weight
4
Q
- Extracellular fluid volume
- Intravascular?
- Interstitial?
A
- 15L
- 20% body weight
- Intravascular (plasma)
- 3L
- 20% of Extracellular fluid (ECF)
- Interstitial
- 12L
- 80% of (ECF)
5
Q
Primary Intracellular ions
A
- K+
- PO43-
- Non-penetrating anions
- Proteins
- Organic anions
6
Q
Primary extracellular ions
A
- Na+
- Cl-
7
Q
Components of a chemistry panel (CHEM-7, BMP)
A
- Na
- K
- Cl
- HCO3
- BUN
- Cr
- Glucose
8
Q
Normal value for Na+
A
135-145 mEq/L
9
Q
Normal value for K+
A
3.5-5 mEq/L
10
Q
Normal value for Cl-
A
95-105 mEq/L
11
Q
Normal value for HCO3-
A
22-28 mEq/L
12
Q
Normal value for BUN
A
7-18 mg/dL
13
Q
Normal value for Cr
A
0.6-1.2 mg/dL
14
Q
Normal value for Glucose
A
70-115 mg/dL
15
Q
What is third spacing?
A
- Shift of fluid from intravascular to interstitial space
- Loss of integrity of vascular endothelium leading to increased permeability
16
Q
Name some areas of third spacing loss
A
- Pancreatitis
- Sepsis
- Surgery
- Hypoalbuminemia (Cirrhosis, etc)
17
Q
What are the goals of giving IV fluids?
A
- Replacement/Resuscitation
- Maintenance
- Electrolyte balance
18
Q
Questions to consider before beginning IV fluids
A
- For replacement, how much extra volume is needed?
- How can we assess volume status?
- What are the sources of volume loss?
- What does it take to maintain normal fluid balance?
19
Q
Common sites/causes of fluid and electrolyte loss
A
- Renal
- GI
- N/V
- NG tube
- Fistula
- Respiratory
- Skin
- Especially burns
- Hemorrhage
- Third-space losses
20
Q
Daily causes for water loss
A
- Urine
- At least 0.5 l/day
- Stool
- 200 mL/day
- Insensible (skin and respiratory)
- 400-500 mL/day
- Endogenous metabolism
- 250-350 mL/day
21
Q
Daily water requirements? How much for maintenance?
A
- Total
- 1400 mL/day
- Maintenance
- Minimum 60 mL/hr
22
Q
Causes for insensible fluid loss
A
- Increased respiratory rate
- Changes in metabolic state
- Body temperature
23
Q
Daily Na+ requirement
A
75-175 mEq Na+/day
24
Q
Daily K+ requirement
A
20-60 mEq K+/day
25
Daily carbohydrate requirements? What does achieving this do?
* 100-150 g/day dextrose
* Reduce protein catabolism and prevent starvation ketoacidosis
26
D5 ½ NS with 20 mEq/L KCL running at 75 mL/hr maintenance will result in what after one day?
* 1.8 L of solution
* 36 mEq K+ (need 20-60 per day)
* 139 mEq Na+ (need 75-175 per day)
* 90 g dextrose (need 100-150 g/day)
Covers nearly all of the needs of the patient
27
How to assess volume status
* Clinical assessment
* Daily Weights
* Intake and Output
* Serum Creatinine
28
Signs of hypervolemia
* AMS
* Increased hepato-jugular reflux
* Increased JVP
* Increased body weight
* Increased fluid balance
* Increased cumulative fluid balance
* Altered capillary refill
* Pitting edema
* 2nd, 3rd space fluid sequestration
* Orthopnea
29
Signs of hypovolemia
* Hypotension
* Tachycardia
* Oliguria
* Decreased skin turgor
* Dry mucous membranes
30
Examples of crystalloid fluids
* Normal saline (NS)
* Lactated Ringer's (LR)
31
Example of colloid fluid?
Albumin
32
Composition of normal saline and risks associated with it
* 154 mEq/L Na+ (140 in plasma)
* 154 mEq/L Cl- (103 in plasma)
* Can lead to hyperchloremic metabolic acidosis (due to high Cl- content)
* Can cause Chloride-mediated renal vasoconstriction
33
A 2018 study of 15,802 critically ill adults given normal saline or a balanced crystalloid (LR or Plasmalyte) found?
* Giving a balanced crystalloid instead of normal saline resulted in:
* Decreased death from any cause
* Decreased new renal replacement therapy
* Decreased persistent renal dysfunction
34
Composition of LR compared to plasma
* Na
* LR: 130 mEq/L
* Plasma: 140 mEq/L
* Cl
* LR: 109
* Plasma: 103
* K
* LR: 4
* Plasma: 4
* Ca
* LR: 3
* Plasma: 4
* Mg
* LR: 0
* Plasma: 2
* Osm
* LR: 273 mOsm/L
* Plasma: 290 mOsm/L
35
Problems with LR
* Blood samples from IV's running LR can give spuriously high serum lactate measurements
* Ionized Ca in LR can bind to citrated anticoagulant in pRBC's and cause clots
* 4 mEq/L of K
* Can cause hyperkalemia
* USe caution in Pts with renal insufficiency
36
Describe colloid fluids such as albumin
* High molecular weight solutions; increase plasma oncotic pressure
* Stay in intravascular space longer than crystalloid fluids
* Albumin has an intravascular half-life of 16 hours
* NS or LR have intravascular half-lives of 30-60 minutes
37
* Describe the following dextrose containing solutions
* D5W
* D5NS
* D10LR
* D5W
* 50g dextrose in 1L free water (5% dextrose)
* D5NS
* 50g dextrose in 1L NS
* D10LR
* 100g dextrose in 1L LR
38
Describe the protein-sparing effect of dextrose containing solutions
* Enough non-protein calories to help prevent endogenous protein catabolism
* Not complete nutrition
* Tube feeds/TPN better
* Dextrose containing fluids can be used to treat ongoing hypoglycemia
39
Main uses of D5W
* Treatment of hypernatremia
* Slowing down correction of hyponatremia
40
Goals of giving maintenance fluid
* Maintain homeostasis in euvolemic patients who cannot accomplish this with oral intake
41
* Examples of common rates of maintenance fluid
* D5 ½ NS with 20 mEq/L of K at 75 mL/hr
* NS at 75 mL/hr (less hypoNa risk) with PRN K repletion
* Decrease to 50 mL/hr in Pts with CHF, CKD, etc.
* Many healthier Pts can tolerate higher rates (e.g. 100-125 mL/hr)
* Be sure to frequently reassess volume status
42
What is the risk of giving maintenance fluids at too high a rate ( \> 50 mL/hr) in Pts with fluid balance disorders such as CHF or CKD
Risk of flash pulmonary edema
43
Goals of fluid replacement (not mantinance)
* Maintain hemodynamic stability
* Replenish intravascular volume
* Fluid Boluses
* 1 L
* 500 mL
* 250 mL
* Special situations
* Reassessment
44
Which patients need aggressive IV fluid treatment?
* Sepsis
* Acute pancreatitis
* DKA/Hyperosmolar hyperglycemic syndrome (HHS)
45
Replacement fluid guide for Spesis
* Initial crystalloid bolus of 30 mL/kg
* More fluid guided by serum lactate and hypotension
46
Replacement fluid guide for Acute Pancreatitis
* **_LR_**
* Initial fluid bolus: 20 mL/kg over 30 minutes, followed by 3 mL/kg/hr for 8-12 hours
47
## Footnote
Replacement fluid guide for DKA/HHS
* 15-20 mL/kg/hr for first 2 hours
* Approx. 1L/hr
* 250-500 mL/hr next few hours
* Then reduce to 150 mL/hr
48
What should you keep in mind about complications of giving replacement fluids?
* Risk of aggressive replacement is acute (flash) pulmonary edema
* In Pts with CHF if boluses are needed for hypotension
* Use 250 mL at most and reassess
49
Guidelines for potassium repletion
* Serum K 3.0-3.4 mEq/L (mild)
* Anticipate 10 mEq administration to increase serum K by 0.1 mEq/L
* Serum K \< 3.0 mEq/L
* Requires more aggressive repletion
* Can do PO and IV
* Recheck more than daily
* Whole-body K deficit often more severe than serum K would suggest
50
In cases where a Pt has low potassium, what else should you check?
* Hypomagnesemia
* Renal potassium wasting
* Hypokalemia will not correct in the presence of hypomagnesemia
Mg level is not part of BMP, need to order separate Mg level test
51
Pearls of IV potassium
* Risk for phlebitis
* Painful
* Limit 10 mEq per 2 hours through peripheral IV
* Central access for faster repletion
52
Guide to treatment for low Mg
* Need to order serum Mg separately from BMP
* Oral replacement does not work well
* Poor GI absorption
* IV Mg
* Give 1-4 g at a time and recheck
53
In Pts with cardiac disease, what are the goal serum K and Mg levels?
* Serum K
* \> 4.0 mEq/L
* Serum Mg
* \> 2.0 mEq/L
54
Quick tips for management of Phosphorus levels
* Need to order serum Phos separately from BMP
* K-Phos neutral (Phos-Nak) tablets
* 1.1 mEq K per tab
* K-Phos IV
* 22 mEq K per 15 mmol
* Na-Phos IV
* No K
* Consider hypophosphatemia in malnutrition or refeeding
* Alcoholics
55
A 38 year old male with PMH of ETOH use disorder presents to the hospital in EtOH withdrawal and severe electrolyte depletion.
On exam his vitals are: HR: 109, RR 18, BP 90/70, Pulse Ox 95%
Gen: ill appearing male, HEENT: Dry CV: Tachy RR
Labs: Na: 131, K: 3.0
What do you want to do?
* A. Give him a beer, it will help his withdrawal
* B. Start maintenance fluids with D5W at 75 ml/hr and Replete his potassium with 40 mEq
* C. Start maintenance fluids with NS 50 ml/hr and replete K with 40 mEq
* D. Give NS bolus 1000ml and replete K with 60 mEq
* D. Give NS bolus 1000ml and replete K with 60 mEq
Bolus will help with low BP
56
A 38 year old male with PMH of ETOH use disorder presents to the hospital in EtOH withdrawal and severe electrolyte depletion.
On exam his vitals are: HR: 109, RR 18, BP 90/70, Pulse Ox 95%
Gen: ill appearing male, HEENT: Dry CV: Tachy RR
Labs: Na: 131, K: 3.0
You give a NS bolus 1000ml and replete K with 60 mEq. However, now he develops Severe Epigastric Pain that radiates to the back … What should you do?
* A. Nothing continue to treat his EtOH withdrawal
* B. Order CBC, LFTs, and Lipase
* C. Start IV PPI and order CBC, LFTs, and Lipase
* D. Continue IVF, start IV pain meds, and continue to monitor
* B. Order CBC, LFTs, and Lipase
57
A 38 year old male with PMH of ETOH use disorder presents to the hospital in EtOH withdrawal and severe electrolyte depletion.
On exam his vitals are: HR: 109, RR 18, BP 90/70, Pulse Ox 95%
Gen: ill appearing male, HEENT: Dry CV: Tachy RR
Labs: Na: 131, K: 3.0
You give a NS bolus 1000ml and replete K with 60 mEq. He develops Severe Epigastric Pain that radiates to the back so you order a CBC, LFTs, and Lipase.
His Lipase comes back 3x the upper limit of normal, his Bili comes back elevated, Hgb is normal
What should you do now?
* A. Start IVF- NS 75 ml/hr, start IV pain control, obtain RUQ U/s
* B. Start IVF- LR 150ml/hr, start IV pain control, Obtain RUQ U/S
* C. Start IVF- LR 150ml/hr, start IV pain control, Obtain CT Abd
* D. Start IVF- D5W 150ml/hr, start IV pain control, Obtain CT Abd
* B. Start IVF- LR 150ml/hr, start IV pain control, Obtain RUQ U/S
58
Pearls of acute pancreatitis (this is how she recommends breaking down diseases to study them for the PANCE)
* Etiology: Most common EtOH vs. Gallstones
* Diagnostics: Presence of two of the following:
* Acute epigastric pain radiating to back
* Lipase 3 times the upper normal limit
* Characteristics of acute pancreatitis on Imaging (CT/MRI/US)
* Fluid of choice: LR
* Treatment: IVF, NPO, Pain Control
