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)
,BEST NUR 2243 EXAM ONE .
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- 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
, BEST NUR 2243 EXAM ONE .
- 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)
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller Ethanhope. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $17.49. You're not tied to anything after your purchase.