acid base balance Flashcards
buffers - 1st line of defense
Combine with acids or base to prevent pH changes
Act Immediately (within 1 second of abnormal pH)
Primary Regulators
PaCO2 - Partial pressure of CO2 in arterial blood (lungs, and you know the range)
Reflection of depth of pulmonary ventilation
Normal range is 35-45mmHg
PaO2 - THIS IS O2, NOT CO2, Partial pressure of O2 in arterial blood - normal range? (partial o2 in my heart and arteries)
No primary role in acid-base balance regulation if within normal limits
Normal range is 80-100mmHg
Oxygen Saturation - range - just pulse ox
Percentage of hgb saturated by oxygen
Normal value is 95-100%
base excess- what is it, and normal range? (b for base, b for buffer at 2)
Amount of blood buffer that exists
Normal value is +/- 2
Base Excess
Base Deficit
Bicarbonate (my kidneys are bi)
major renal component of acid-base balance. excreted and reproduced by the kidneys to maintain normal acid-base.
2nd line of defense - respiratory
Responds within minutes to hours to changes in acid/base to eliminate or retains CO2.
3rd line of defense - renal system
most adequate - if kidneys are functioning. Responds within hours to days (last line of defense; may take hours or days to restore normal hydrogen ion concentration)
ph
Metabolic and respiratory processes work together to keep H+ levels within a normal range
anion gap
when high- ex. ketones.
Reflection of anions not routinely measured.
Normal: Usually caused by loss of bicarb i.e. diarrhea, diuretics
gap—between the negatively charged and positively charged electrolytes in your blood.
how to obtain arterial blood gases
Heparinized syringe
Blood from an artery
Make sure at least 15-20 minutes have passed after procedures
Apply pressure for 5 minutes
On ice
Prompt delivery to lab
ph and calcium
have inverse relationship - high ph, low calcium, vice versa
crystalloids (krystle goes everywhere)
Solutions with small molecules that flow easily from the bloodstream into cells and tissues
isotonic solutions
to correct volume w/out an net movement. used to treat simple dehydration.
Same concentration of osmotically active particles in ECF
Osmotic pressure is the same inside and outside
Fluid doesn’t shift between extracellular and intracellular areas
blood loss administer what? (need to equalize the blood loss)
isotonic solution to correct imbalance.
isotonic solution (sugar and salt are isotonic)
Examples
Dextrose 5% in water (remember dangers associated with D5W!!)
0.9% Sodium Chloride (Normal Saline) Actually 154mEq Na+
Lactated Ringers -
Plasmalyte
D5 risk
brain cell swelling
hypotonic solution - fluid moves from what to what?
Less concentrated than extracellular fluid
Fluid will move from blood stream into cell
hypertonic solutions
Draws fluid from intracellular space, causing cells to shrink and extracellular space to expand
colloids
Plasma expanders used if blood volume doesn’t improve with crystalloids
Pulls fluid into bloodstream
Needs close monitoring
no lower extremities IV
risk of blood clot
needle gauges
Higher the gauge, smaller diameter of angiocath
Increased fluids over short amt of time
Routine IV fluid administration
macrodrip is always what number?
you’ll be given that info on the package. could be 10 drops/1 mL. microdrip is always 60.
infiltration is (infiltrate the cold)
cool to touch
phlebitis is
hot to touch
assess IV site how often?
every hour. Assessment
Infiltration
Phlebitis
Review complications
Dressing Changes/tubing changes
Site Changes
transfusions
Restores blood volume or corrects deficiencies in blood’s oxygen carrying capacity or coagulation components
Requires consent
Review in Taylor & Hinkle: Administration - Assessment - Symptoms of transfusion reaction - Interventions for reaction
always hang normal
saline. no other solution is acceptable.
acid base balance
body maintains slight alkyline at 7.35 - 7.45`
If PaO2 drops below 60mmHg
then will see a large drop in saturation
ex of buffers (C and the 2 Ps are buff)
Carbonic acid-sodium-bicarbonate, protein & phosphate buffering systems
Hypoxemia (literally look at the word - emia) may cause
- anaerobic metabolism
- hyperventilation
If PaO2 drops below 60mmHg, then…
will see a large drop in saturation
renal system secretes..and reabsorbs what?
hydrogen (H+) ions and reabsorbs bicarbonate (HCO3) ions
renal system - Reabsorption and secretion of
Reabsorption and secretion of electrolytes (e.g., Na, Cl)
pH is a measure of..
hydrogen ion concentration in body fluids
bicarbonate - Principle buffer of intra or extracellular fluids?
extracellular fluids in the body
anion gap - normal range (ana’s gap was normal at 12)
Normal range is 12mEq/L (+/-2)
reasons for loss of anion gap
diarrhea (at risk for metabolic acidosis)
increase in anion gap (ana dropped increased acid)
Seen with lactic acidosis or ketoacidosis (DKA)
ex of colloids (collide with albumin and dex)
Albumin
- Dextran
osmolality of isotonic solutions (numbers) (Isotoners cost 275)
275-290mOsm/L
isotonic solution - good choice for what disorder? (dehydrated isotoners)
Therefore good choice for ECF dehydration.
hypotonic osmolality (think of oz normal range)
Osmolality less than 275mOsm/L
hypotonic used to treat what?
used for hypernatremia
hypotonic - used to dilute what? (think salt)
Used to dilute ECF and rehydrate cells
Used for hypertonic imbalances
hypertonic osmolality (think of the normal range)
Solutions with osmolality greater than 295mOsm/L
bicarbonate is where
in the kidneys
diarrhea is a loss of (base out your butt)
bicarbonate
treatment for metabolic aklylosis (sodium flushes the bi)
sodium chloride (helps flush excess bicarbonate)
best to treat dehydration and blood loss (dehydrated with isotoners size 9)
isotonic ie saline 9% or dextrose 5% in normal water (d5W) 275 - 290 mOs/L
hypotonic (not toned at 75)
.45% sodium chloride (1/2 normal saline) less than 275
hyper
3% saline (dangerous) greater than 295 mOs/L
