Week 14 - Fluid & Electrolytes Flashcards
1
Q
Goals of fluid management? Maintain adequate: (5)
A
- Intravascular fluid volume
- Left ventricular filling pressure
- Cardiac output
- Systemic blood pressure
- Oxygen delivery to tissues
2
Q
How can you assess fluid status in a patient?
A
- Skin turgor
- Mucus membranes
- Peripheral pulses
- Resting heart rate and blood pressure
- Orthostatic changes
- Urine output
- NPO Status
3
Q
Body fluid composition percentages:
A
Extracellular: (33%)
- Interstitial (25%)
- Plasma (8%)
Intracellular: (66%)
4
Q
Intracellular fluid (ICF) make up ___ of the body’s water and it is around _____% of your weight.
A
2/3;
40
5
Q
The body is ___% water.
A
60
6
Q
The intracellular fluid is primarily a solution of:
A
Potassium (K+)
Organic anions
Proteins
the cell membranes and cellular metabolism control these
7
Q
The extracellular fluid is ____ of the body’s water and around _____% of body weight.
A
1/3
20%
8
Q
The extracellular fluid is primarily a _____ and ____ solution.
A
NaCl and NaHCO3
9
Q
The interstitial fluid (ISF) and Plasma are part of the _______ fluid.
A
Extracellular
10
Q
Characteristics of the interstitial fluid (ISF):
A
- Surrounds the cells and does not circulate
- comprises 3/4 of the ECF
11
Q
What are transcellular fluids? Characteristics?
A
- fluids that are outside of the normal compartments.
- 1-2 liters of fluid comprise the CSF, digestive (gastric) juices, mucus, etc/
12
Q
Basic constituent of the human body
A
Water
13
Q
Total body water (TBW) varies with age, gender and body type. What are the differences in percentages for males, females, and infants?
A
Males: 60%
Females: 50%
Infants: 80%
14
Q
Which patients generally have less water per kg of body weight?
A
- Obese adults
- Patient’s with diabetes.
15
Q
What are the characteristics of Hypovolemia? (7)
A
- Increasing Hematocrit
- Metabolic acidosis
- Urine SG >1.010
- Urine Na (less than) < 10 mEq/L
- Urine osmolality < 450mOsm/kg
- Hypernatremia
- BUN: creatinine ratio > 10:1
16
Q
Signs of Hypovolemia at 5% water loss:
Mucus
LOC
Orthostatic
HR
BP
Urine output
Pulse rate
A
17
Q
Signs of Hypovolemia at 10% water loss:
Mucus
LOC
Orthostatic
HR
BP
Urine output
Pulse rate
A
18
Q
Signs of Hypovolemia at 15 - 20% water loss:
Mucus
LOC
Orthostatic
HR
BP
Urine output
Pulse rate
A
19
Q
When evaluating a hypovolemic patient, keep in mind that a drop in BP does not occur in a patient that is already in the supine position until ______% of the blood volume is lost.
A
30
20
Q
What is the intraoperative goal for urine output in normal patients? and for burn patients?
A
- 0.5 – 1 mL/kg/hr
- 1.5 mL/kg/hr
21
Q
Decrease in urine output generally does not occur until _______% of blood volume is lost
A
~20
22
Q
Early and later signs of Hypervolemia:
A
- Pitting edema
- Presacral edema
later:
- Tachycardia
- Crackles
- Wheezing
- Pulmonary edema
23
Q
The Chest X-ray is reliable to evaluate for hypervolemia. What would you see on it?
A
- Kerly B lines: increased pulmonary and interstitial markings.
- Diffused alveolar infiltrates
24
Q
What labs can you check for hypervolemia?
A
Blood and urinalysis
25
Extracellular Fluid:
Major cations (+)
Major anions (-)
Major cations (+): Sodium, Potassium and **Calcium**
Major anions (-): Chloride, Bicarbonate and Proteins
26
Intracellular Fluid:
Major cations (+)
Major anions (-)
Major cations (+): Potassium, **Magnesium** and Sodium
Major anions (-): Chloride, Bicarbonate and Proteins
27
Most important electrolytes? and why?
Potassium and Calcium
Effect excitability of nerve & muscle
**K+** effects *resting membrane potential (RMP)*
**Ca++** determines *threshold potential*
28
Sodium ( ____ - _____ mEq/L)
135 - 145
29
Hypernatremia is secondary to: ____________.
Lack of water;
*Not because of too much* salt*.
30
Neuro symptoms of hypernatremia (Na > **_____** mEq/L):
**>145**
*Neuro*: *Symptoms reflect rate of H2O movement out of brain cells*
- Altered LOC
- Weakness
- Thirst
- Restlessness
- Lethargy
- Seizures
- Death
- **Intracranial bleeding: ruptured cerebral veins/ focal hemorrhage (with rapid decreases in brain volume).**
31
CV and Renal symptoms of hypernatremia:
- Hypovolemia
_________
- Polyuria, Oliguria
- Renal insufficiency
32
Characteristics of hypernatremia in conjunction with **normal** total body sodium content: (4)
- Most common cause is **diabetes insipidus**
- Marked impairment in renal “concentreating -ability”
- Decreased ADH secretion
or
- Failure of the renal tubules to respond normally to circulating ADH (polyuria).
33
Characteristics of hypernatremia in conjunction with **low** total body sodium content:
- Patients has lost sodium and water
- Water loss is *greater* than sodium loss
- Losses can be renal (osmotic diuresis) or extrarenal (diarrhea or sweat).
34
Hypernatremia in conjuction with **increased** total body sodium content is most commonly caused by:
- The administration of large quantities of hypertonic NA solutions (3% NaCl or 7.5% NaHCO3).
- Cushing's syndrome can also cause.
35
Treatment of hypernatremia:
- Water (fluid) deficits corrected over **~48 hours** with *hypotonic* solution, such as **D5W**.
- Loop diuretic, then water deficit replacement
- Decreases in sodium concentration should not be faster than 0.5 -1 mEq/L/hour
36
Elective surgery should be postponed until sodium level is < ______ mEq/L and H2O deficits corrected.
150
37
Hyponatremia is associated with:
- Alcoholism
- Liver failure
- Severe burns
- Malignant neoplasms
- Hemodialysis
- Sepsis
38
Hyponatremia is serum Na < ______ mEq/L and neurologic symptoms occur with a level below < ________mEq/L
135;
120
39
Hyponatremia clinical manifestations include:
Neurological:
- Seizures → Coma
- Cerebral edema
- Agitation, Confusion
- Headache
Gastrointestinal:
- N & V → anorexia
Musculoskeletal:
- Cramps and weakness
40
Diagnosis of hyponatremia is based on the assessment of
serum osmolality and volume status
41
________ is the most common electrolyte disorder and may be classified as:
Hyponatremia;
Hyponatremia - isotonic or pseudo
Hyponatremia – Hypertonic
Hyponatremia – Hypotonic
42
What is osmola**l**ity?
number of osmoles of solute per kilogram of water (e.g., weight)
43
what is osmola**r**ity?
number of osmoles of solute per liter of water (e.g. fluid)
44
What is tonicity?
Effect a solution has on cell volume
- Hypertonic
- Hypotonic
- Isotonic
45
Characteristics of Isotonic or Pseudo-Hyponatremia (3)
1. Normal Osmolality (280 – 295 mOsm/kg)
2. Total normal sodium
- Reflects fluid shifts from ICF --> ECF
- Decreased plasma sodium levels
46
Isotonic or Pseudo-Hyponatremia may occur with what conditions or medications?
Hypothyroidism
Glucocorticoid insufficiency
SIADH
______
Amitriptyline
Cyclophosphamides
Tegretol
Morphine
47
Pseudohyponatremia
48
SIADH characteristics
- clinical euvolemia
- Inappropriately **elevated urine osmolality (>300mOsm - 400)**
- in the face of **low serum osmolality (<280 mOsm/kg)**
- Urine NA> 20- 30 mEq/L
- Normal renal function
49
Causes of SIADH (5)
- Pulmonary carcinoma
- Brain metastases, other malignancies
- CNS disorders
- Idiopathic forms – frequent occur in older patients
- Medications
50
Medications that cause SIADH (6):
- Vasopressin
- HCTZ
- Antidepressants agents (SSRIs)
- NSAIDS
- Vincristine
- Oxytocin
- Neuroleptic agents
51
What is the acute treatment of SIADH for someone with severe hyponatremia ( <110 mEq/liter) ?
- IV lasix
- NS with 20 - 40 mEq/L KCL
- Rarely will 3% saline will be utilized
52
Chronic treatment of SIADH:
- Water restriction to ~1000ml per day
- Declomycin
- Vasopressin receptor antagonist: conivaptan, vaprisol, tolvaptan, samsca, lithium.
- Urea
- PO salt tablets
53
charactristics of Hyponatremia- Hypertonic:
High osmolality (>295 mOsm /kg)
Hypervolemia that may be caused by:
- Mannitol Excess
- Glycerol Treatment
- CHF
-Cirrhosis
54
Treatment to Hyponatremia- Hypertonic
Salt restriction
or
Water restriction
or
Diuretics
55
Characteristics/Causes of hyponatremia - hypotonic:
Low serum osmolality (<280 mOsm/kg)
Hypovolemia may be due to:
- GI losses
- Renal losses plus excess water ingestion
- Diuretics
- Ketonuria
- 3rd spacing
- Adrenal insufficiency
- N&V
56
Excessively rapid correction of hyponatremia has been associated with?
Demyelinating lesions in the pons ( pontine myelinolysis ) that can lead to permanent neurological damage!
57
S/S of pontine myelinolysis:
- Balance problems
- Confusion, delirium, ∆s in consciousness
- Difficulty swallowing, dysphagia
- Hallucinations, speech changes, poor enunciation
- Tremors, weakness in the face, arms, or legs, usually affecting both sides of the body.
- Acute progressive quadriplegia
58
Considerations / correction rates of hyponatremia if patient is symptomatic?
- Consider treatment with 3% NaCl
- Initial: sodium 1-2 mEq/L/hr x **2 hours** then --- > 0.5 mEq /L/hr
59
Correction rates of hyponatremia if patient is asymptomatic?
- Consider sodium 0.5mEq/L/hr
60
Max sodium correction rate in 24 hr:
10 mEq TOTAL rise
61
Max sodium correction rate in 48 hr:
18 mEq TOTAL rise
62
Potassium lab range:
(3.0 – 5.5 mEq)
63
What is hyperkalemia?
- Increase in total K content
- Altered distribution of K between intra- & extracellular sites
- Adverse effects are secondary to acute ↑ in serum concentration.
64
Most detrimental effects of hyperkalemia occur in cardiac conduction system. What are they?
- Prolonged PR interval
- Widening QRS complex
- Peaked T wave
65
Causes of hyperkalemia K+> 5.5: (9)
- Acidosis
- Hemolysis
- Tissue necrosis
- Renal insufficiency and failure
- K+ sparing diuretics
- **Hypo**aldosteronism
- Suppliementation
- Salt substitutes
- Rapid infusion - banked blood
66
Clinical manifestation of hyperkalemia? (7)
- Tall, peaked T waves
- Wide QRS
- Ventricular arrhythmias
- Muscle weakness
- Confusion
- Paresthesia
- Cardiac arrest
67
Treatment of Hyperkalemia (6)
- NaHCO3 (~50 mEq) promotes cellular uptake of K+ within 15 minutes (*Note: cannot be used alone*)
- Beta agonists
- Glucose 30-50 g + Insulin 10 units (can take up to 1 hour)
- Hyperventilation
- Hemodialysis
- Calcium
68
Why is calcium given for hyperkalemia? and how much?
- Administration of Ca++ will protect ♥ from hyperkalemia (1 amp = 1 gm Calcium Chloride)
- Ca++ will *decrease* excitability and **depress** the membrane threshold potential.
- Ca++ 500-1000 mg IV partially **antagonizes** cardiac effects; effects rapid but short-lived
Careful: Ca++ potentiates digoxin toxicity
69
What is hypokalemia?
Decreased total body potassium
Altered distribution
70
Changes in EKG with hypokalemia:
Flattened T waves and presence of U wave
71
__________ change in arterial ph can change plasma K+ concentration by ___________ meq ( _________ proportional relationship)
0.1;
0.6
indirectly
72
Causes of hypokalemia:
- Thiazide, loop diuretics
- Aminoglycosides
- Adrenal steroids
- Chronic laxative abuse
- Vomiting
- Gastric outlet obstruction
- Gastric suction
- Severe diarrhea
- Poor dietary intake
- Therapeutic **alkalinization** of the urine
- **Hyperaldosteronism**
- Cushing syndrome
- Magnesium deficiency associated with alcoholism
- Renal tubular acidosis
- Salt-losing nephropathies
73
Treatment of Hypokalemia:
- Oral replacement with potassium chloride : 60-80 mEq/day is safest .
- Peripheral IV potassium should not exceed >8 mEq/hr so as not to irritate veins.
- Central IV K + can be infused at 10-20 mEq/hr
74
Remember that NMBD dose should be decreased by _____ - ___% since hypokalemia causes **increased sensitivity** to NMBDs.
25-50
75
Normal calcium range:
8.5 - 10.5 mg/dl
76
Hypocalcemia causes: (6)
- Hypoparathyroid
- Pancreatitis
- Renal failure
- Decreased serum albumin levels
- Bone cancer
- Insufficient vitamin D
77
Why should you avoid hyperventilation with hypocalcemia?
Alkalosis should be avoided to prevent further decreases in Ca2+.
**0.1 <** in arterial ph can decrease ionized Ca concentration by **0.16** mg/dL
78
Heart effects with mild and severe hypocalcemia:
Mild: broad based **tall peaking T waves**
Severe:
- extremely wide QRS,
- low R wave,
- disappearance of p waves,
- tall peaking T waves
79
Signs of hypocalcemia: (7)
- Skeletal muscle spasm including *laryngospasm/bronchospasm*
- Decreased myocardial contractility
- Hypotension
- HF
- Tetany
- **Trousseau's sign**
- **Chvostek's sign**
80
Trousseau’s Sign is seen with:
Hypocalcemia
81
Chvostek’s Sign is seen with:
Hypocalcemia
82
Symptomatic hypocalcemia is a true medical emergency! What is the treatment ?
1. Rule of 10's:
- Infusion of 10ml of 10% calcium gluconate over 10 minutes (or calcium chloride).
2. Followed by a continuous infusion of elemental calcium **0.3 - 2mg/kg/hr**
3. Follow serial ionized Ca+ levels
4. check magnesium: consider giving **magnesium 1G**
83
Hypercalcemia Values:
Serum Ca+ > 10.5;
Ionized >5.6 mg/dL
84
Hypercalcemia causes:
- Hyperparathyroidism
- Malignancy - bone
- Renal Failure
- Thiazide Diuretics
- Excess Ca+ supplements
85
Hypercalcemia clinical signs: 7
HTN
Dysrhythmias → **Congenital Heart Block (CHB)**
**Shortened QT**
Sedation
Polyuria
Anorexia
*Pancreatitis*
86
Treatment of Hypercalcemia
- Rehydration with NS followed by brisk diuresis (200 - 300 ml/hr) with loop diuretic to accelerate calcium excretion.
- Follow serial ionized calcium levels
- Avoid acidosis, since it may further elevate calcium levels
87
Normal magnesium range
1.7 – 2.2
88
What causes hypomagnesemia < 1.7
- Alcoholism
- Chronic diarrhea, polyuria, sweating
- Hyperaldosteronism
- Malnutrition
- Malabsorption syndromes, such as **celiac disease and IBS.**
- Medications:
- Diuretics
- Aminoglycoside
- Antibiotics
- Chemotherapy
89
Symptoms of hypomagnesemia: 7
- Abnormal eye movements ( **nystagmus** )
- Seizure
- Fatigue
- **Muscle spasms or cramps**
- Muscle weakness
- Numbness
- Dysrhythmias
90
Treatment of hypomagnesemia:
- IV magnesium sulfate 1- 2 grams given slowly over 60 minutes.
- Monitor labs for concomitant hypokalemia or hypocalcemia.
- Monitor EKG for arrhythmias ( similar to hypokalemia).
91
S/S of hypermagnesemia >2.2: (8)
- **Flushing**
- N/V
- Drowsiness
- Weakness
- **Loss of patellar reflex, decreased DTRs**
- **Respiratory depression**
- Cardiac arrest
- Coma
92
Treatment of Hypermagnesemia
- Stop all sources of Mg.
- IV calcium 1 gram - can temporarily antagonize most effects.
- Loop diuretic with rehydration of **D1/2 NS** enhances magnesium excretion.
93
What should you monitor with hypermagnesemia?
Monitor for vasodilation and negative inotropic effects
94
With hypermagnesemia you should decrease the dosages of NDMB by:
25- 50%
95
PeriOperative Fluid Therapy goals:
- Replacement of pre-existing fluid deficits
- Replace normal losses (maintenance requirements)
- Replacement NPO deficit
- Replacement of surgical wound losses (e.g., “third space losses” and blood loss)
96
acute chemical pneumonitis caused by the aspiration of stomach contents in patients under general anesthesia.
Mendelson syndrome
97
Why are NPO guidelines enforced?
due to risk of pulmonary aspiration
98
Prolonged fasting can contribute to:
- Hypovolemia
- Hypoglycemia
- Anxiety
99
Traditional NPO Guidelines for adults:
No solid food for 8 hours pre-op;
*most medications can be continued with a small sip of water (excluding some **cardiac** and **diabetic** meds)*
100
Longer fasting times should be enforced in those patients at an increased risk for aspiration:
- Renal failure
- Increased ICP
- Decreased LOC
- Cerebral palsy
- Anorexia
- Esophageal disorders
- Diabetes
- Delayed gastric emptying
- Difficulty swallowing
101
Traditional NPO Guidelines for pediatrics:
Up to 2 hours pre-op: clear liquids.
Up to 4 hours pre-op: Human breast milk.
At least 6 hours pre-op: Infant formula, nonhuman milk, light meal:
Up to 8 hours pre-op: “full” meal, carbonated drinks
*No chewing gum or mints after midnight*
102
refers to patient-centered, evidence-based, multidisciplinary team developed pathways for a surgical specialty and facility culture to **reduce** the patient’s surgical stress response, optimize their physiologic function, and facilitate recovery.
Enhanced Recovery after Surgery (ERAS®)
103
What is the 4-2-1 Rule?
It calculates the **hourly maintenance**:
4 cc/kg/hr first 10 kg of body weight
2 cc/kg/hr second 10 kg
1 cc/kg/hr for the remaining weight kg
104
NPO Deficit
equals the number of hours the patient is NPO x the hourly **maintenance rate**
105
After calculating NPO deficit, how are fluids administered?
Administer:
- 50% during the 1st hour.
- 25% in the 2nd hour.
-25% in the 3rd hour.
106
Typical fluid output sources:
- Urine (may be measured by Foley and a urometer).
- Respiratory tract
- Evaporative losses
- Losses due to surgical wound and/or bleeding
- Insensible or “third spacing” losses
107
Tissue manipulation & surgical trauma supports movement of fluid from the **ECF compartment** into **non-functional** compartments, and are called:
3rd space fluid losses.
108
**Intra-operative Fluid loss**
Small Incision/minimal trauma:
Moderate Incision/moderate trauma:
Large/Incision/severe trauma:
Major vascular case/extreme trauma:
- 4-6 ml/kg/hr
- 6-8 ml/kg/hr
- 8-10 ml/kg/hr
- 10-12 ml/kg/hr
109
Crystalloids: contain **electrolytes** dissolved in water or dextrose and water.
What are some examples
- 0.9% Normal saline: “isotonic”; 9 gm of NaCl per 1 liter of fluid.
- Lactated Ringer’s.
110
Colloids are ______ or _______ molecules, somewhat **impermeable** to vascular membrane.
natural or synthetic.
111
What do colloids do?
They determine the *colloid osmotic pressure* that balances distribution of water between **intravascular** and **interstitial** spaces
112
Examples of colloids
- 5% albumin
- 6% hydroxyethyl starch (Hespan, Hextend)
113
used for most neurological or renal patients; or with blood administration.
What fluid?
NaCl 0.9%
114
Plasmalyte contains:
Magnesium
Acetate
Gluconate
115
Lactated ringers contains:
Sodium
Potassium
Chloride
Calcium
Dextrose
Lactate
116
D5W – contains _____ gm dextrose per liter
5
117
used for volume expansion; each has limitations.
What fluids?
Dexran/Hespan/Hetastarch
118
what are Balance Salt Solutions (BSS) ?
They are fluids that have an electrolyte concentration similar to ECF.
119
Characteristics of Normal Saline Solution?
what happens if you give too much?
- Contains more chloride than ECF.
- Too much can cause **hyperchloremic-induced metabolic acidosis**
120
Normal Saline Solution is good choice for which patients?
Good choice for renal (diabetic) and neurosurgical patients.
121
When are Dextrose Containing Solutions used?
- In prevention of hypoglycemia in neonates and pediatric patients.
- In conjunction with insulin infusions.
122
Hyperglycemia is associated with increased risk for:
ischemic neurologic injury.
123
Advantages of Crystalloids (5):
- Inexpensive
- Promotes urinary flow
- Restores third - space loss.
- Used for extracellular fluid repletion
- Used for initial resuscitation.
124
Disadvantages of crystalloids (5):
- Dilutes plasma proteins
- Causes reduction in capillary osmotic pressure.
- Causes peripheral edema
- Has transient effect
- Potential for pulmonary edema.
125
Colloid advantages (6):
- Causes sustained increase in plasma volume
- Requires smaller volumes for resuscitation.
- Causes less peripheral edema.
- Tends to remain intravascular.
- causes more rapid resuscitation
- Useful in conditions of altered vascular permeability.
126
Colloid disadvantages (7):
- Expensive
- Can cause coagulopathy: (Dextran > hetastarch > Hextend).
- Can cause anaphylactic reaction (dextran)
- Decreases Ca2+ (albumin).
- Can cause renal failure (dextran).
- Can cause osmotic diuresis
- Can cause impaired immune response (albumin).
127
When is hypertonic saline beneficial?
in fluid resuscitation from shock/trauma and major surgical losses.
128
Hypertonic Saline is commercially available in:
2% or 3 %.
129
Hypertonic Saline indicated for? (6)
- Major surgical procedures: aortic, radical cancer surgeries
- Shock
- Slow correction of hyponatremia.
- TURP syndrome
- Reduce perioperative edema.
- Reduce ICP
130
Hypertonic Saline effects:
- Hypernatremia
- Hyperosmolality
- Hyperchloremia
- Increased cardiac output
- Increased solute to kidneys
- Improved microcirculatory blood flow
- Decreased potassium: **Hypo**kalemia
- Decreased SVR/PVR;
- Decreased ICP
131
What is albumin?
Pooled plasma in saline
132
Albumin is:
1. ________ soluble
.
2. _________ protein.
3. Accounts for ____- ___% of the colloid osmotic pressure of plasma.
-- _____ % - rapid intravascular **volume expansion**.
--- ______% hypoalbuminemia
1. Highly
2. Globular
3. 70 - 80%
-- 5%
-- 25%
133
Albumin has an intravascular half-life of ________ hours.
> 24 hours
134
Crystalloids or Colloids?
Most perioperative volume deficits are _______.
_________ solutions eventually equilibrate between **plasma** & **interstitial** space therefore more is needed to maintain intravascular volume
ECF
Crystalloid
135
T/F albumin and plasma derivatives:
1. you need ABO compatibility
2. They have no coagulation factors
3. safe for critically ill patients
1. False... not needed.
2. True.
3. False: associated with increased mortality in critically ill patients
136
How is the possibility of transmission of blood- borne disease eliminated for albumin?
it is heat treated at 60 degrees C for 10 hours
137
Dextran is composed of ________ ________ molecules.
Intravascular half-life _____ hours.
polymerized glucose;;
6
138
Dextran's potential complications include: (7)
- Anaphylaxis,
- Volume overload
- Pulmonary edema,
- Cerebral edema
- *Platelet* dysfunction
- Acute renal failure
- PT. w/ hx of diabetes mellitus = renal insufficiency at ↑ risk.
139
non-ionic starch derivatives (2)
Hetastarch, Voluven
140
Hextend (6% in HES in ____)
LR
141
Hespan (6% HES in _____)
NS
142
Hextend & Hespan are
________ polymer and contain:
Synthetic
___________
Sodium
Potassium
Calcium
Magnesium
143
Hextend & Hespan intravascular half-life :
>24 hours
144
Synthetic plasma expanders
**Anaphylactoid** reactions have been reported with both ______ and ________, but much rarer with _________.
dextran;
hetastarch
hetastarch
145
Ultimately indication for blood transfusion:
to maintain oxygen-carrying capacity to the tissues.
146
When blood loss occurs replace with _____ or _______ to maintain intravascular volume until risk of anemia outweighs the risk of the blood transfusion.
crystalloids or colloids
147
Healthy patient **without cardiac disease**: can usually tolerate decrease in Hgb to __________ or a Hct ___________.
7 - 8 g/dL
21-24%
148
what happens when hemoglobin is <7 g/dL?
- the resting cardiac output increases to maintain normal O2 delivery -----> *myocardial strain*
- Morbidity & mortality rates start to be affected.
149
Generally, a hemoglobin of __________ is limit for elderly and those with existing cardiac/pulmonary disease.
9 - 10 g/dL
150
Evaluating Blood Loss:
Soaked 4 x 4 contains:
Soaked “lap sponge” contains:
~10 ml of blood
~100 ml of blood
151
Fluid replacement
to blood loss ratios:
Crystalloids:
Colloid:
3:1
1:1
152
To Transfuse or Not to Transfuse:
what should you keep in mind?
- You must anticipate on a patient to patient basis.
- The minimum Hgb level that will avoid organ damage due to O2 deprivation.
- Balance between O2 delivery (DO2) and O2 consumption (VO2)
153
Factors that increase O2 demand and effect O2 delivery:
- Inability to increase CO
- Shifts to the oxyhemoglobin curve
- Inadequate oxygenation
- Abnormal Hgb
154
Assessment of Fluid Resuscitation includes:
- HR,
- BP,
- U/O,
- Arterial oxygenation,
- pH
155
In adults, _________ is an insensitive, nonspecific indicator of hypovolemia.
tachycardia
156
What strongly suggest adequate fluid replacement?
eservation of BP and a CVP of 6 - 12 mmHg
157
In procedures with large fluid losses, an arterial line is more accurate at estimating BP than indirect measures. Variations in the a-line waveform during positive pressure ventilation may indicate :
hypovolemia
158
EBV
Estimated blood volume
159
ABL
Allowable blood loss
160
Estimated Blood Volume (EBV)
Premature Neonates:
Term Neonates:
Infants & Children:
Adult Males:
Adult Females:
- 95 ml/kg
- 85 ml/kg
- 80 ml/kg
- 75 ml/kg
- 65 ml/kg
161
Allowable Blood Loss equations:
162
Routine typing of blood is performed to
identify antigens on the erythrocyte membranes (A, B, Rh)
163
Antibodies (anti-A, anti-B) are formed whenever membranes lack what?
and
what are these antibodies capable of causing?
lack A and/or B antigens
They are capable of causing rapid **intravascular destruction** of erythrocytes that contain the *corresponding antigens*.
164
Red cell membranes contain at least ______ different antigenic systems
300
165
Chromosomal locus produces 3 alleles: _ _ _.
and each represents an enzyme that modifies a cell surface _______ , producing a different antigen.
A, B, and O
glycoprotein
166
The Rh system is based on:
only the presence or absence of the most common, **immunogenic allele**, the D antigen.
167
________ of caucasians have the D antigen.
Individuals lacking this are called _______.
80-85%
Rh -
168
How can someone develop antibodies against the D antigen?
After exposure to a previous Rh-positive transfusion
or
Pregnancy (Rh-negative mother delivering an Rh-positive baby).
169
ABO blood grouping ...exposure.
170
Compatibility Testing
**Type Specific:**
what does it do?
- ABO-Rh typing only 99.8% compatible.
- Requires 5-15 minutes
171
Compatibility Testing
**Type and Screen: **
and
what is the screen portion detecting?
- ABO-Rh and screen; 99.94% compatible
- Requires 15-45 minutes
-Screen (indirect **Coombs test**) detects presence of antibodies in serum that are most commonly associated with *non-ABO hemolytic* reactions.
172
Compatibility Testing
Type and cross match:
What does it do?
- ABO-Rh, screen, and crossmatch;
99.95% compatible
- Mimics transfusion; donor cells are mixed with recipient serum
- Confirms ABO-Rh typing (in < 5 min)
- Detects antibodies to other blood group systems.
- Detects antibodies in low titers or those that do not agglutinate easily
- *Takes at least 45 mins or more if patient has received prior transfusions!*
173
For a transfusion what compatibility test:
1. Always want to use:
2. In an emergency – can use:
3. Last resort will be:
1. typed & cross-matched blood.
2. type-specific, uncross-matched blood
3. O negative blood.
174
Packed Red Blood Cells (PRBCs) contain:
- RBC’s,
- WBC’s,
- Platelets,
- Reduced plasma
175
Packed Red Blood Cells (PRBCs) are use for:
Used to restore oxygen-carrying capacity and for controlled surgical blood Loss.
176
Packed Red Blood Cells (PRBCs) usually contain a volume between:
and a hematocrit of :
250- 350 ml
70%
177
What is "washed PRBCs"? And who is it generally used for?
complete removal of plasma.
For neonatal transfusions
or
patients with a history of severe transfusion reaction, immunocompromised patients
178
1 unit PRBC increase Hgb by _____ **gm/dl** or Hct by ________.
- 1 g/dl
- 2- 3%
179
PRBCs administration steps:
- NS to decrease viscosity, increase speed of administration.
- Utilize fluid warmer to avoid hypothermia.
- Use 170 micronfilter to trap clots & debris.
180
PRBCs tubing should contain _____ - ______ **mm** filter to trap clots and debris (degenerated platelets, leukocytes, fibrin).
170 - 230 mm
181
PRBCS should be warmed to?
and why?
- Warm to 37*C
- Hypothermic effects and low levels of 2,3 DPG in stored blood cause leftward shift of oxygen Hgb dissociation curve --> tissue Hypoxia.
182
Why should PRBCs be infused with NS and not glucose or LR?
- Glucose solutions may cause RBC **hemolysis**
- LR contains calcium and may induce clot formation.
- NS, albumin, and FFP are all compatible with PRBC.
183
Whole blood volume and Hct:
Volume 450 - 500 mL
40% Hct
184
Whole blood is used primarily in :
- hemorrhagic shock (massive blood Loss; >25% of EBV).
185
Whole blood contains:
all factors:
RBC’s,
WBC’s,
Platelets,
Plasma - including factors V and VIII
185
Whole blood contains:
all factors:
RBC’s,
WBC’s,
Platelets,
Plasma - including factors V and VIII
186
Unit of whole blood will raise Hct ________ and Hgb ________ gm/dL
3-4%
1
187
With whole blood:
*Platelet activity decreases to < ______% after 24° storage;
If given within ______° after collection, it delivers functional platelets*.
5;
6
188
Cons of Whole blood:
- Not economical for routine use d/t blood shortages.
- Increased risk of allergic transfusion reaction
189
In Emergency Transfusions: if the type is known, what can confirm ABO compatibility?
an abbreviated cross-match can be done in 5 min. (type- specific).
190
universal donor
O Rh-negative
191
In emergency transfusions:
If > _______ or more units of O Rh-negative given, screen recipient’s blood for antibodies before **own** type given.
2
*Old school: must continue to use O - even after type known ( True only for Whole blood, not PRBC.)*
192
O+ can also be given in emergency transfusions, just not to:
women of childbearing age.
193
If > ______ units of O- given, continue with it.
Can go back to type specific blood in ___ - ____ months (RBC last ~ 120 days)
10;
3-4
194
Fresh Frozen Plasma contains:
plasma proteins & clotting factors.
No platelets
195
Fresh Frozen Plasma Utilized in:
- coagulation deficiencies.
- reversal of **warfarin** therapy.
- microvascular bleeding.
196
1 unit of FFP will increase clotting factors by _______%
3%
197
What could result from massive transfusion of FFP?
Hypernatremia
198
Thrombocytopenia (Platelet count less than <___________)
50,000
199
1 unit of Platelet concentrate increase platelet count by _______ to _________.
5,000 to 10,000
200
Each unit of platelet contains about ______ ml of ________.
50ml of plasma.
*presence of plasma poses a risk of transfusion reaction*
201
what is Cryoprecipitate?
Fraction of plasma that precipitates once FFP is thawed
202
Cryoprecipitate has high concentrations of what two things and help to treat what?
- High concentrations of Factor VIII to treat Hemophilia A.
- High concentrations of fibrinogen to treat Hypofibrinogenemia
202
Cryoprecipitate has high concentrations of what two things and help to treat what?
- High concentrations of Factor VIII to treat Hemophilia A.
- High concentrations of fibrinogen to treat Hypofibrinogenemia.
203
Transfusion Reactions
Febrile Reaction facts:
- Most common with a 1% incidence
- Increase in temperature by 1 degree C
204
Transfusion Reactions
Allergic Reaction facts:
- 2nd most common
- Pruritus, hives increase in temperature
205
Transfusion Reactions
What is a Hemolytic Reaction? and number of occurrences? and fatal in how many?
- ABO incompatibility
- 1 in 6000 transfusions
- Fatal in 1 in 100,000
206
Common cause of hemolytic reaction in a transfusion?
Patient mis-identification is the common cause
207
Presumptive diagnosis of hemolytic reaction is based on:
Free Hgb in urine & plasma
208
Steps to take if a transfusion reaction is suspected: (5)
1. stop transfusion
2. treat hypotension.
3. consider steroids.
4. send donor blood and patient blood sample for crossmatch.
5. Preserve renal function by maintaining brisk urine output (IVF, Lasix, Mannitol).
209
After a blood transfusion reaction pt's blood sample is sent for a crossmatch and what other tests?
- Free Hgb.
- Haptoglobin
- Coomb's test
- DIC screening
210
Infection complications/occurrences with a blood transfusion:
- Hepatitis B (1: 220,00)
- Hepatitis C (1:1.6 M)
- HIV (1:1.8 M)
- rare bacterial infections
211
Besides infection, what other complications can occur from blood transfusions?
- Transfusion Related Acute Lung Injury (TRALI)
- Hyperkalemia
- Acidosis
- Hypothermia
212
Storage temp for banked blood:
1 – 6 degrees C to slow glycolysis
213
Biochemical changes in stored blood: (8)
1. Progressive **acidosis** due to RBC metabolism (pyruvic and lactic acid).
2. Increased K: **21 mEq**
3. Increased pCO2: **140 mmHg**
4. Increased lactate
5. Decreased glucose
6. Decreased 2,3 DPG
7. Decreased platelets
8. Decreased Factor V (15%) and Factor VIII (50%)
214
pH of blood at collection and 21 days later:
pH at collection 7.1; pH at 21 days 6.9
215
what is CPD (citrate-phosphate-dextrose)?
and what does each of its ingredients do?
and shelf life?
A banked blood preservative.
Citrate: anticoagulant that binds with ionic calcium; prevents clotting
Phosphate: acts as buffer
Dextrose: substrate used for glycolysis of RBC for energy
Shelf life: 21 days
216
What is CPDA (citrate-phosphate-dextrose-adenine)?
what does it do?
and shelf life?
A banked blood preservative.
Includes adenine (adenosine) for incorporation into ATP and extra glucose to prolong storage;
**most common**
Shelf life: 35 days
Hct 70-80%
217
whats a complication of MASSIVE blood transfusion? and why does it occur?
**Citrate intoxication**: from the addition of CPD as preservative for stored blood; can occur with rapid transfusion **(>150ml/min)**.
218
Citrate is mainly metabolized by ?
what happens if rate of transfusion is too fast?
liver;
If rate of transfusion exceeds **1 unit of blood per minute** in an adult, *decreased calcium* may result (binds calcium and magnesium)
Due to accumulation of **citrate-chelating** serum calcium
Pediatric patients and those with liver disease are more likely to become intoxicated
219
Symptoms of Citrate Intoxication
- Hypocalcemia
- Hypotension
- Increased LVEDP
- Increased CVP
- Prolonged QT interval
- Hypomagnesemia manifesting as tachyarrhythmias, TdP, or refractory V Fib
220
Treatment of Citrate Intoxication
- Calcium or magnesium
- Citrate will be metabolized quickly in Kreb’s cycle so symptoms may abate before treatment needed
- Supportive treatment
221
Transfusion blood is routinely screened for:
HIV 1/2
Hepatitis B and C
- Hepatitis C (nonA/nonB): **most symptomatic (90%)**
HTLV1/2 (human T-cell lymphocytic virus)
Syphilis
222
Request “______ Negative” blood;
it is used for immunocompromised like BMT or organ transplants, and infants.
______ is the MOST COMMONLY TRANSMITTED VIRUS in blood transfusions.
CMV;
CMV
223
Others Diseases That Can Be Transmitted in Blood
exposure.
224
What is TRALI?
Transfusion-Related Acute Lung Injury (TRALI)
is a non-cardiogenic form of **pulmonary edema** associated with blood product administration.
225
TRALI occurs more frequently with what blood products?
RBCs
FFP
Platelets
226
TRALI occurence and mortality rate:
- 1 in 5000 units transfused
- TRALI-mortality rate of 5 to 8%
227
The clinical appearance of TRALI is similar to:
adult respiratory distress syndrome (ARDS)
228
TRALI S/S:
- Symptoms usually begin within 6 hours after the transfusion.
Often more rapidly, the patient develops:
- Dyspnea
- Cyanosis
- Chills
- Fever
- Hypotension
- Noncardiogenic pulmonary edema.
229
On CXR TRALI reveals
bilateral infiltrates
*Severe pulmonary insufficiency can develop*
230
TRALI treatment:
- Supportive tx.
- Transfusion stopped.
- Oxygen and ventilatory support - with a low tidal volume strategy to prevent barotrauma.
231
Dilutional Coagulopathy is seen with:
Massive transfusions > 1 EBV (or >10 units)
**I don't know what they mean by 1 EBV?
232
Signs of Dilutional Coagulopathy
Microvascular bleeding
Hematuria
Bleeding at IV sites
Clinically oozing
**Increased PT/PTT**
Decreased platelets
233
Treatment for Dilutional Coagulopathy
- Surgically control the bleeding.
- Keep patient warm
- Maintain perfusion and euvolemia.
- Don’t overhydrate and further dilute patient
- Consider FFP, platelets
- Consider Vitamin K, DDAVP (enhances platelet adhesiveness).
234
Alternatives to Traditional Blood Transfusion Therapy
- Normovolemic hemodilution
- Cell saver: 50 - 60% Hct (intraop salvage).
- Autologous donation (pre-op).
- Postop salvage (chest tube drainage system).
- Oxygen-carrying substitutes (Bovine blood/ Petroleum- based therapies).
235
Complication with postop salvage.
- reinfused anticoagulants,
- dilutional coagulopathy,
- air embolism
*Can’t reinfuse blood if it contains pus, malignancy, or spilled GI contents*
