Exam 2 Flashcards
- The primary goal of acid-base homeostasis is to maintain which of the following?
To maintain normal pH
- What is the primary buffer system for fixed acids?
HCO3
- The majority of acid the body produces in a day is excreted through the lungs as CO2. What happens to the H+ ions?
They bind to an OH forming H2O excreted from the kidneys
- If the blood PCO2 is high, the kidneys will do which of the following?
Excrete greater amounts of H+ & reabsorb more HCO3
- Which of the following mechanisms helps to eliminate excess H+ via the kidneys?
Reabsorption of HCO3-, phosphate & ammonia buffering
- What is the primary chemical event in respiratory acidosis?
Increase in blood CO2 levels
- What is a normal response of the body to a failure in one component of the acid-base regulatory mechanism?
Compensation
- Compensation for respiratory acidosis occurs through which of the following?
Increase in blood HCO3 levels
- Which of the following accurately describes compensation for acid-base disorders?
Kidneys take hours to days to compensate for respiratory disorders
- A patient has a pH of 7.49. How would you describe this?
Alkalosis
- Which of the following clinical findings would you expect in a fully compensated respiratory acidosis?
Normal pH, ↑ PaCO2, ↑ HCO3
- How is acute respiratory acidosis accomplished?
For an acute increase in PCO2, the plasma (HCO3- increases by apporximately 1 mEq/L for every 10 mmHg PCO2 rise above 40 mmHg
- What is the most common cause of respiratory alkalosis?
Hypoxia
- Which of the following are signs and symptoms of acute respiratory alkalosis?
Convulsions, dizziness, paresthesia
- In a patient with partially compensated respiratory alkalosis, which of the following blood gas abnormalities would you expect to encounter?
Increased pH, Decreased CO2, Decreased HCO3
- What is a normal anion gap range?
+/-12 (8-16 mEq/L)
- A patient has an anion gap of 21 mEq/L. Based on this information, what can you conclude?
Metabolic acidosis
- In a patient with Kussmaul’s respirations, what acid-base disturbance would you expect to see?
Metabolic Acidosis, Keto acidosis
- What is the treatment for severe metabolic acidosis?
NaHCO3
- Which of the following states that the rate of gas diffusion is inversely proportional to the weight of the gas?
Graham’s Law
- Correction of metabolic alkalosis may involve which of the following?
Restoring normal fluid volume
Administering acidifying agents
Restoring normal K+ and Cl- levels
- What is the normal range for BE?
+/-2 mEq/L
- What cation is the most prominent in the intracellular compartment?
Potassium
- What is the most common cause of hyperkalemia?
Kidney disease
- Which of the following drugs can be used to temporarily lower K+ in severe hyperkalemia?
Insulin, calcium gluconate, Na+ salts, or large volumes of hypertonic glucose.
If those measures fail, peritoneal or renal dialysis can aid in K+ removal
- Which of the following describes serum Ca2+?
Ionized
protein bound
complex
- Clinical signs of hypokalemia would include which of the following?
muscle spasms and rapid respirations. muscle weakness and cardiac dysrhythmias. confusion and irritability
- What are normal values for serum Mg2+?
1.7-2.1 mEq/L
- What is the normal range for serum phosphate?
1.2-2.3 mEq/L
- Which of the following values would be increased for a patient with COPD?
PaCO2
- Which of the following substances is(are) almost totally reabsorbed from the tubules?
Sodium (Na)
Potassium (K)
Chloride (Cl)
-Bicarbonate (HCO3)
- Which of the following mechanisms control potassium excretion?
Aldosterone
- Which of the following organs is the most powerful and complete in its ability to restore a normal pH?
Kidneys
- What is the normal range for BUN?
8-23 mg/dL
- What is the normal range for creatinine?
0.7-1.3mg/dL
- Which factors are considered when predicting lung volumes?
age height gender ethnicity sometimes weight
- Approximately how much of a forced expiratory maneuver is effort dependent?
30%
- Normally, the percentage of the total volume exhaled during an FEV1 by a 20 year old individual is?
83%
- The volume of air that can be exhaled after a normal tidal volume exhalation is the
Expiratory Reserve Volume (ERV)
- At sea level, the alveolar water vapor pressure is normally about
47 mm Hg
PAO2 equation
(Pb - PH2O)FiO2 – (PaCo2 * 1.25)
mmHg
CcO2 equation
(Hb * 1.34) + (PAO2 * 0.003)
mL/dL O2
CaO2 equation
(Hb * 1.34 * SaO2) + (PaO2 * 0.003)
mL/dL O2
CvO2 equation
(Hb * 1.34 * SvO2) + PvO2 * 0.003)
mL/dL O2
Total oxygen delivery
Qt (CaO2 * 10)
mLO2/min
Arterial-venous oxygen content difference
C(a-v) O2 = CaO2 – CvO2
mL/dLO2
Intrapulmonary shunting Qs/Qt
(CcO2 – CaO2)/(CcO2 – CvO2)100
%
Oxygen consumption VO2
Qt(C(a-v)O2 * 10)
mLO2/min
Oxygen Extraction Ratio
[C(a-v)O2 /CaO2]100
%