Lecture 4/24 - Acid/Base Flashcards
Final (90 cards)
________ ⇋ Strong bases + H⁺
Weak conjugate acid
Strong bases want to ________ a proton and create _______.
Accept
Weak conjugate acids
________ ⇋ Weak bases + H⁺
Strong conjugate acid
Weak bases want to ________ a proton and create _______.
Accept
Strong conjugate acids
Equation: Buffer
Buffer + H⁺ ⇋ HBuffer
What is the function of buffers?
To correct acidosis or alkalosis by stabilizing pH
Ionized buffers: binds with free protons to help correct acidosis (Buffer + H⁺)
Nonionized buffers: Can donate protons to help correct alkalosis (HBuffer)
What are the main 3 buffers in the body?
- Bicarb (predominant ECF)
- Proteins (2nd most important)
- Phosphate (predominant ICF; important in plasma despite low concentration in ECF)
Kidneys use ________ to buffer urine to prevent a _______ pH during urination
Ammonia
Low → painful
T/F: A buffer is best at buffering a pH that is close to its pKa value.
True
This gives you 50% ionized & 50% nonionized → Buffer can either donate or accept protons
The pK of HCO₃⁻ as a buffer is _____ and it is the best buffer in the body for preventing ______.
6.1
Acidosis
The ______________ refers to the fact that all buffers work together at the same time with different pKa’s and work on the same pool of protons to maintain pH
Isohydric principle
Blood buffer graph: what does the buffer line represent?
Combination of bicarb, proteins, phosphate
Blood buffer graph: Why is albumin not included in the buffer line? What does it more so concern?
Amount of albumin in plasma is extremely small compared to large amount of Hb/protein inside RBC
Important w/ osmotic pressure & keeping fluid within the CVS
T/F: Hb is found in the plasma
False
Hb is a component of the ICF of RBC
Hematocrit of the blood is ____. For every liter of blood _____ cc is RBC.
0.4
400 cc
(within this is alot of Hb)
Blood buffer graph:
Adding more Hb = line gets ______. How does this affect the buffering system?
Line gets steeper (more vertical)
Better buffering system
Blood buffer graph:
Subtracting more Hb = line gets ______. How does this affect the buffering system?
Line gets flatter (more horizontal)
Less effective buffering system
Blood buffer graph:
How does the isobars change with Hb?
Increase Hb: Isobars come closer to the 40mmHg isobar (compressed)
- Greater change in bicarb when +/- CO₂ → helps block some of the pH changes
- Better buffer
Decrease Hb: Isobars spread farther from the 40mmHg isobar (stretched)
- Less change in bicarb when +/- CO₂ → Not able to cope w/ pH changes → Larger pH changes
- Less effective buffer
The lungs are the _____ buffers & the kidneys are _______ buffers.
Short term
Long term
How does the kidneys assist with acid/base balance?
Excrete protons (via urine)
Reabsorb protons
Excrete bicarb (urine)
Reabsorb bicarb
Create new bicarb
The graph with the flower that has all the acid/base conditions is called a ________. What is it used for?
nomograph
- Cause of acid base problems
- Determine appropriate treatment
Nomograph:
Acute Respiratory Acidosis
Respiratory Acidosis → Reduction in drive to breathe
Acute → Kidneys are not adjusting
pH: ↓
PCO₂: ↑
HCO₃⁻: ↑
H⁺ : ↑
Rationales:
Increased PCO₂ + H₂O (in blood) = Increased HCO₃⁻ + H⁺
H⁺ that is created is decreasing the pH
- HCO₃⁻ is acting as a weak base → does not want to accept proton
Nomograph:
Acute Respiratory Alkalosis
Caused by breathing too much (hyperventilation):
- Head injury
- Asthma attack
- Anxious
- Seizure
pH: ↑
PCO₂: ↓
HCO₃⁻: ↓
H⁺: ↓
(Isobar to the R )
———————-
Rationales:
- Decreased PCO₂ → ↓HCO₃⁻
- Decreased H⁺ → ↑pH
Nomograph:
Chronic Respiratory Acidosis
pH: Small ↓
PCO₂: Small ↑
HCO₃⁻: Large ↑
H⁺: ↑
——————-
Rationale:
pH & CO₂ compensated by kidneys
- Kidneys help with large increase HCO₃⁻
- Kidneys pump H⁺ into urine to help pH