NUR 2243 EXAM 1 Questions and Answers- Florida State College at Jacksonville

NUR 2243 EXAM ONE
 ARTERIAL BLOOD GASSESS (ABGs): acid-base balance is the process of regulating the pH,
bicarbonate concentration and partial pressure of carbon dioxide of body fluids. It is a dynamic
interplay between three processes: acid production or intake, acid buffering, and acid excretion.
*critical in maintaining homeostasis in the body!
 Acid- release hydrogen (H+) ions
 Base- takes up hydrogen (H+) ions
o Bicarbonate- the most important base in the body (which consists of carbonic acid
[weak acid] & bicarbonate [base]).
 Buffer Systems
1. Chemical Buffers- albumin, Hcg, globulins
1. Respiratory system
 Hypoventilation- retain CO2 (acidotic)
 Hyperventilation- losing too much CO2 (alkalotic)
1. Kidneys (takes the longest to work but they keep the pH balanced longer)
 Kidneys movement of bicarb--> Formation of acids and ammonium--> flushed
out of the urinary systems.

 Metabolic Acidosis:
o Causes- DKA, HHS, renal insufficiency (can't get rid of toxins), aspirin toxicity, severe
diarrhea, malnutrition, shock
o Signs & symptoms- H/A, N/V, decreases muscle tone & reflexes, warm & flushed
skin, decreased BP, hyperkalemia, kussmaul resp., decreased bicarb
o Assessment- Hyperpnea and Kussmaul respirations (fast & deep) -- lungs are trying
to compensate so the person is blowing off too much CO2
o Interventions-
 Hydration
 Antidiarrheals
 Bicarb (only w low serum level)
 DKA- give insulin via IV
 AKI- administer dialysis, low protein, high-calorie diet
o Ways to avoid metabolic acidosis: take insulin as prescribed, place aspirin away
from children, get to dialysis as scheduled (so there is not a buildup of acid)
o S/S- kussmaul, warm flushed skin, decreased bicarb.
If a person has severe diarrhea and they are becoming acidotic GIVE THEM BICARB!

 Metabolic Alkalosis
o Causes- diuretics, excessive vomiting or GI suctioning, ingestion of a lot of excess
sodium bicarb or antacids (tums)
o With TPN patients are at a higher risk for metabolic alkalosis. May have a positive
Chvostek’s sign
o Assessment- RR &depth decrease to compensate by conserving CO2, paresthesia of
extremities, dysrhythmias, tachycardia
o Signs & Symptoms- confusion, anxious, hypoventilation, tachycardia (bc K is low),
N/V/D, tremors, muscle cramps
o Interventions-
 Safety precautions (they are fall risks) bc of muscle weakness
 Potassium chloride

 Respiratory Acidosis
o Hypoventilation--> hypoxia
 (retention of CO2 by lungs)

, o Causes- Acute Respiratory depression, anesthesia, overdose, increased ICP, airway
obstruction, decreased alveolar capillary (pneumonia, COPD, ARDS, PE)
o Assessment-
o Signs & symptoms- decreased BP, rapid & shallow respirations, skin & mucous are
pale/cyanotic, H/A, lethargic, dizzy, hyperkalemia, dysrhythmias, muscle weakness
o Interventions:
 Focus on improving ventilation & O2 (maintain patent airway)
 Drug therapy:
 Bronchodilators
 Mucolytics
 Anti-inflammatories
 Oxygen therapy
 Pulmonary hygiene
 Ventilation support
 Prevention of complications

 Respiratory Alkalosis
o Causes- hyperventilation (fear, anxiety, PE, fear), mechanical ventilation (settings
may be too high), high altitudes
o Assessment-
o Signs and symptoms- hyperventilation, tachycardia, decrease of normal BP,
hypokalemia, numbness & tingling of extremities, seizures, irritable
o Interventions:
 Keep Pt hydrated
 Slow down respirations/ change ventilator settings
 HAD (high altitude disorder)

When a Pt has a seizure, they can have a combo of metabolic acidosis & acute respiratory acidosis
bc of the heavy muscular contractions and lack of air exchange.
As a nurse, give them O2 bc their brain is not receiving O2 during seizures. So, by giving them O2
it returns them to homeostasis/ balanced out quicker!


pH 7.35-
7.45

PaCO2 35-45

HCO3 22-26

PO2 80-100

SPO 95-100%




 pH- The negative logarithm of H+ concentration
 PaCO2- The partial pressure of CO2 in the arterial blood
o It indicates how well the lungs are excreting carbonic acid
 HCO3- Indicates how well the kidneys are excreting metabolic acid.

REMEMBER!
1. Look at pH first (7.35-7.45)
- Low pH= acidosis

, - High pH= alkalosis
2. CO2 out of normal range? (35-45) = Respiratory issue
3. HCO3 out of normal range? (22-26) = Metabolic issue
4. Determine if there is any compensation
- (fully compensated if pH is normal)
5. Evaluate the PaO2 (80-100) and O2 saturation (95-100)
- Low PaO2 indicates an alteration in respiratory function or breathing air w a low level
of O2.
- SaO2 & PaO2 are directly related—as one increases, the other usually does too.
- Oxygen is present in the blood in 2 forms: (if they are below normal—there is
evidence of hypoxemia).
i. O2 dissolved in the blood
ii. O2 combined w hemoglobin


 ROME
 Respiratory Opposite Metabolic Equal
 If pH & PCO2 arrows are opposite the disorder is respiratory in origin.
 If pH & HCO3 arrows are same direction the disorder is metabolic in origin.
PH PCO2 HCO3
Resp. Acidosis ↓ ↑ Norm.
Resp. Alkalosis ↑ ↓ Norm.
Met. Acidosis ↓ Norm. ↓
Met. Alkalosis ↑ Norm. ↑

 Compensation
 Uncompensated
o The cause is uncompensated if the pH is anywhere outside the normal range
(greater than 7.45 or less than 7.35). Also, the value (CO2 or HCO3) that does not
match the pH will still be in the normal range
o pH abnormal.; CO2 OR HCO3 abnormal.
 Partial Compensation
o The cause is partially compensated if the pH is anywhere outside the normal
range, and the value that does not match the pH (CO2 or HCO3) will be outside its
normal range. This indicated the body is attempting to get the pH back to
normal.
o All 3 abnormal
 Complete Compensation
o The cause is compensated if the pH is anywhere inside the normal ranges
between 7.35 and 7.45. (if pH is normal it is always compensated)
o pH norm.; CO2 AND HCO3 abnormal.


 FLUID & ELECTROLYTES

 Sodium
o Hypo: Lethargy, confusion, decreased LOC, weakness, muscle cramping, seizures,
anorexia, nausea, vomiting, osmolality imbalance.
o Hyper: Thirst, dry sticky mucous membranes, weakness, elevated temperature, severe
hypernatremia causing confusion and irritability, decreased LOC, hallucinations, and
convulsions.
o How does sodium impact the body? Regulates/maintains H2O balance, regulates plasma
osmolality (# of dissolved particles in a fluid)