ABG Interpretation CHA 1

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respiratory acidosis lab values

pH<7.35
PCO2 >45

causes of respiratory acidosis

hypOventilation caused by:
-OD of narcotics/alcohol
-tumor
-COPD and other respiratory conditions (severe asthma and emphysema)
-neuromuscular disease that affects the respiratory system (Myasthenia Gravis, GB syndrome)
-pulmonary edema
-airway obstructio

signs and symptoms

-dyspnea
-cyanosis
-muscle twitching
-sweating
-HTN
-decreased LOC
-peripheral vasodilation
-cardiac dysrhythmias

Treatment for respiratory acidosis

-treat underlying condition
-mechanical ventilatory support to help "blow off" CO2
-focus is on increasing ventilation (C&DB, reverse sedation, bag/intubate)

what will NOT fix respiratory acidosis

Oxygen

respiratory alkalosis lab values

pH > 7.45,
CO2 < 35 mmHg

causes of respiratory alkalosis

Hyperventilation (pt. blows off too much CO2) caused by:
� Fear
� Pain
� Increased respiratory rate in very ill patient
� Post-op patient on ventilator, overventilation
� Voluntary over breathing, ie. anxiety, fever
� High altitude
� Hypoxia
� Initial sta

S/S of respiratory alkalosis

� Decreased LOC
� Seizures
� Decreased BP
� Hypokalemia
� Dizziness
� Light-headedness
� Paresthesia's
� Palpitations

treatment of respiratory alkalosis

-Treat underlying cause.
-Slow down the respiratory rate by reassuring the patient, sedation, and/or have them breathe into a paper bag.

metabolic acidosis lab values

pH <7.35
HCO3 <22

Causes of metabolic acidosis

body gains acid or loses bases by
-diarrhea
-drainage of pancreatic juices
-intestinal fistula
-renal failure
-diabetic ketoacidosis
-lactic acidosis
-shock
-salicylate OD
-sepsis

signs and symptoms of metabolic acidosis

-hypOtension
-deep and fast breathing (Kussmal's)
-disorientation
-drowsiness
-lethargy, coma
-poor peripheral circulation
-hyperventilation (secondary to compensation)
-cardiac dysrhythmias

treatment for metabolic acidosis

-ID and reversal of cause
-IV sodium bicarb may be required
-support BP by volume or inotropes
-treat dysrhythmias

metabolic alkalosis lab values

pH >7.45
HCO3 >26

Causes of metabolic alkalosis

body loses acids or gains bases by
-prolonged vomiting
-NG suctioning
-diuretic abuse
-sodium bicarb OD
-overuse of antacids
-hyperaldosteronism
-Cushing's syndrome

signs and symptoms of metabolic alkalosis

-mental confusion
-stupor
-apathy
-muscle weakness (secondary to low potassium)
-dizziness
-tetany
-convulsions
-hypOventilation (secondary to compensation)

treatment for metabolic alkalosis

-treat underlying cause
-potassium replacement
-saline infusion

in acidosis, pH.....

decreases

in alkalosis, pH.....

increases

if CO2 has the opposite relationship to the pH, then the imbalance is...

respiratory

if HCO3 has the same relationship to the pH, then the imbalance is...

metabolic

when does compensation occur?

pH is in the normal range of 7.35-7.45

if the condition is a respiratory imbalance, look at the ___ to determine state of compensation

HCO3

If HCO3 is normal, then the condition is...

uncompensated

if HCO3 is abnormal, then the condition is...

partially compensated

if the condition is a metabolic imbalance, look at the ___ to determine state of compensation

CO2

if the CO2 is normal, then the condition is...

compensated

if the CO2 is abnormal, then the condition is..

partially compensated

pH 7.58
CO2 20
HCO3 19

alkalosis
respiratory
partial compensation

pH 7.72
CO2 48
HCO3 35

alkalosis
metabolic
partial compensation

pH 7.64
CO2 47
HCO3 30

alkalosis
metabolic
partially compensated

pH 7.34
CO2 51
HCO3 37

acidosis
respiratory
partially compensated

pH 7.8
CO2 29
HCO3 24

alkalosis
respiratory
uncompensated

pH 7.16
CO2 46
HCO3 38

acidosis
respiratory
partially compensated

pH 7.68
CO2 52
HCO3 34

alkalosis
metabolic
partially compensated

pH 7.65
CO2 28
HCO3 17

alkalosis
respiratory
partially compensated

pH 7.33
CO2 32
HCO3 18

acidosis
metabolic
partially compensated

pH 7.12
CO2 28
HCO3 13

acidosis
metabolic
partially compensated

The nurse is evaluating the laboratory work of a patient who has uncontrolled metabolic acidosis. Which outcome would result from this condition?
A.pH 7.40
B.PaO2 98 mmHg
C.Bicarbonate 38 mEq/L
D.Serum potassium of 5.7 mEq/L

D. Serum Potassium of 5.7 (because the kidneys aren't working)

Which of the following would be associated with metabolic acidosis?
A Central nervous system depression
B Increased serum bicarbonate level
C Prolonged vomiting or gastric suctioning
D pH greater than 7.40

A.
Central nervous system depression

A patient diagnosed with diabetes mellitus has not been following his established meal plan and did not eat lunch today. What is an expected outcome for this patient?
A Metabolic acidosis
B Metabolic alkalosis
C Respiratory acidosis
D Respiratory alkalosi

A.
Metabolic acidosis

The nurse is reviewing standing orders for a pt who has chest pain. The pt has hx of COPD, lab results show he has mild respiratory acidosis. The nurse would question which order?
A.Encourage oral fluids
B. Keep HOB elevated
C. O2 therapy at 4 L/min
D. Be

C. O2 therapy at 4L/min

The nurse is caring for a client with an NG tube that is attached to low suction. The nurse monitors the client for manifestations of which disorder?
A. Metabolic acidosis
B. Metabolic alkalosis
C. Respiratory acidosis
D. Respiratory alkalosis

B. Metabolic alkalosis(Stomach contents are acidic- NG tube is pulling all that out to make body system more basic)

A client with a 3-day history of nausea and vomiting presents to the emergency department. The client is hypoventilating and has a respiratory rate of 10 breaths/min. Arterial blood gases are drawn and the nurse reviews the results, expecting to note whic

D. An increased pH with an increased HCO3.

A nurse caring for a client with an ileostomy understands the the client is most at risk for developing which acid-base disorder?
A. Metabolic Acidosis
B. Metabolic Alkalosis
C. Respiratory Acidosis
D Respiratory Alkalosis

A. Metabolic Acidosis(Intestinal secretions are high in bicarbonate)

A patient has experienced several fractured ribs after being involved in an automobile accident. She is receiving pain medication frequently. What is an expected outcome for this patient?
A Metabolic acidosis
B Metabolic alkalosis
C Respiratory acidosis
D

C.
Respiratory acidosis

A patient is experiencing a cardiac arrest. A possible outcome for this patient in the form of acid-base imbalance is:
A Metabolic alkalosis
B Respiratory alkalosis
C Metabolic alkalosis and respiratory alkalosis
D Metabolic acidosis and respiratory acido

D.
Metabolic acidosis and respiratory acidosis