Laura Barron, Module 2
Acid-Base Disturbances - Brunners
Ratio
20parts of HCO3- (Bicarbonate) : 1part H2CO3 (Carbonic Acid)
CO2 is a potential Acid. When dissolved in water → H2CO3 Carbonic Acid
Regulation by Kidney – Slow
R Acidosis & most cases of M Acidosis:
K. ↓ (excrete) H+ and ↑ (conserve) HCO3R & M Alkalosis
↑ H+ ↓ HCO3Kidney Failure M Acidosis cannot be
compensated

Regulation by Lungs – Control by
Medulla O.
M. Acidosis
↑ respiration ↓ CO2
M. Alkalosis
↓ respiration rate ↑ CO
Acute and Chronic Metabolic Acidosis (Base Bicarbonate Deficit)
↓ pH and ↓ bicarb (allowing the high acidic value)
Anion Gap
Na+ + K+ - Cl- - HCO3- = Anion Gap
Norm: 12-16mEq/L or 8-12 w/o K+


>16 acidosis (Normal anion gap) resulting from:
loss of bicarbonate: diarrhea, lower intestinal
fistulas, diuretics, early renal insufficiency,
excess admin chloride, admin of nutrition w/o
bicarbonate (lactate) = hyperchloremic
acidosis.
 >30 metabolic acidosis regardless of pH and
HCO3-. resulting from: ketoacidosis, lactic
acidosis, salicylate poisoning, starvation.
 Negative gap is rare caused by hypoproteinemia.
o s/s: Clinical manifestations – headache, confusion, drowsiness,
increased resp rate/depth, N & V. Seen in Chronic Renal Failure.
o Assessment and diagnostic Findings
 HCO3- < 22
ph<7.35
 Hyperkalemia may occur, and then shift back into the cell after.
 Hyperventilation decreases CO2 – Compensatory action.
o Medical Management – bicarbonate (low ca treated first from chronic met
acidosis to avoid tetany)
Acute and Chronic Metabolic Alkalosis (Base Bicarbonate Excess)
Laura Barron, Module 2
high pH high bicarbonate. Vomiting, gastric suction. loss of potassium from
diuretic. Excessive adrenocorticoid hormones, hypokalemia, excessive ingestion of
antacids.
o Clinical Manifestations – tingling of fingers and toes, dizziness,
hypertonic muscles. Respirations depressed as compensatory action by
lungs. tachycardia, decreased motility and paralytic ileus. as K+
decreases chronic met alk. has premature ventricular contractions or U
waves on ECG.
o Assessment and Diagnostic Findings – ph > 7.45, hco3- > 26mEq/L
o Medical Management – monitor I/O because of fluid loss.IVF NS
w/chloride allows binding with bicarb to excrete. Then any treatment of
KCL Acute and Chronic Respiratory Acidosis (Carbonic Acid Excess)
ph< 7.35, paCO2 > 42. Always due to inadequate excretion of CO2 – ventilation.
Acute pulmonary edema, aspiration of a foreign object, Atelectasis, Pneumothorax,
overdose of sedatives, sleep apnea syndrome, impaired respiratory muscles –
mechanical ventilation.
o Clinical Manifestations – increase pulse and respiratory rate, incr
blood pressure, feeling of fullness in head, mental cloudiness.
increased cerebral blood flow. Chronic – emphysema, bronchitis,
obesity. COPD may not develop symptoms of Hypercapnia because of
compensatory renal changes have occurred.
o Assessment and Diagnostic Findings - ph< 7.35, paCO2 > 42, chest xray
ECG
o Medical Management – improve ventilation Bronchodilators, Antibiotics,
Thrombolytics/anticoagulants. Pulmonary hygiene to clear resp tract of
mucus. Adequate Hydration! O2 as necessary. Decrease elevated paCO2
slowly. Semi-Fowler’s position to expand chest wall.
o pco2 > 50 chronically – O2 may cause carbon dioxide narcosis when
removing the stimulus of hypoxemia. Extreme caution.
 Acute and Chronic Respiratory Alkalosis (Carbonic Acid Deficit)
ph > 7.45 paco2 < 38. Always caused by Hyperventilation blowing of co2. causes
extreme anxiety, hypoxemia, salicylate intoxication
o Clinical Manifestations – light headedness Vaso Constriction, decreased
cerebral blood flow. inability to concentrate, numbness and tingling
from decreased calcium, tinnitus, LOC, Tachycardia, Dysrhythmia.
o Assessment and Diagnostic Findings – Compensated state kidneys have
lowered bicarb to near normal level. Toxicology screen should be
performed to rule out salicylate intoxication.
o Medical Management – if Anxiety. Breathe slowly to allow CO2 to
accumulate or into paper bag. sedative.
 Mixed Acid-Base Disorders
normal pH with changes in paco2 and hco3-. (Can’t have mixed R Acid & R Alka – you
can’t hyper and hypo ventilate.) Met Acid and Resp Acid – during respiratory and
cardiac Arrest.
o Compensation – lungs and kidneys compensate to return the pH to normal.
o Blood Gas Analysis –