Unformatted text preview: AcidBase Evaluation
Nsg. 2041 Adult Health Nursing Curry College 1 AcidBase Imbalance Homeostasis requires a balance of acids (H+ hydrogen ions) and bases or alkaline substances (bicarbonate) Metabolic and respiratory processes must work together to keep H+ levels normal and stable Physiologic Buffers Pulmonary system (lungs) controls the carbonic acid concentrations , Renal system (kidneys) controls bicarbonate concentrations 2 Arterial Blood Gases ABG's Determines acid base balance Components of arterial blood Determines arterial oxygenation pH 7.357.45 PaCO 3545 mmHg 2 HCO3 2226 mEq/L PaO2 80 100 mmHg
3 ABG's Component that determines oxygenation is the paO2= 80100 mmHg (also described as pO2)
(Partial pressure of oxygen dissolved in arterial blood) 4 Arterial Oxygenation / paO2 80100 mmHg= normal 6080 mmHg= mild hypoxemia 4060 mmHg= severe Hypoxemia 5 Evaluating AcidBase Balance Step 1 Evaluate the pH What is it? Step 2 Evaluate ventilation (respiratory Within normal limits Too high Too low component) pCO2
What is it? Too high Too low Within normal limits
6 Step Three Evaluate Bicarbonate Component What is it? Within normal limits Too high Too low 7 Evaluate Compensation Mechanisms What is the pH Is it normal? Is it below 3.40? Is it above 3.40? What is the PaCO2
8 Types of AcidBase Imbalances Without Compensation Respiratory Acidosis Metabolic Acidosis Respiratory Alkalosis Metabolic Alkalosis 9 Respiratory Acidosis Causes
Hypoventilation R/t Drug overdose Chest trauma Pulmonary Edema COPD Airway Obstruction Neuromuscular disease pH= <7.35 PCO2 = Increased HCO3 = Normal
10 Respiratory Alkalosis Causes
Hyperventilation R/t Anxiety High Altitude Pregnancy Fever Pulmonary Embolism pH= >7.45 PCO2= Decreased HCO3= Normal 11 Metabolic Acidosis Causes
DKA (diabetic ketoacidosis) Diarrhea Renal failure Shock Salicylate Overdose pH= <7.35 PCO2= Decreased HCO3= Decreased
12 Metabolic Alkalosis Causes Loss of gastric Secretions Overuse of antacids Gastric suctioning Vomiting Potassium wasting diuretics pH= >7.45 PCO2= Increased HCO3= Increased
13 When in ClassThink R0ME
To determine the cause of an imbalance I just use the pH and the PaCO2 Draw arrows for pH and PCO2 In Respiratory Disorders, the two arrows point in opposite direction In Metabolic Disorders, the arrows point in the same direction
14 Here is how the arrows will point
pH PCO2 Respiratory Acidosis Down Up Respiratory Alkalosis Up Down Metabolic Acidosis Down Down Metabolic Alkalosis Up Up
15 Checking for Compensation Body tries to restore a normal PH by altering the buffer system component that is not involved in the imbalance. Fully compensated will provide a normal PH with an abnormal PaCO2/HCO3 pH within normal limits/abnormal PaCO2 Use 7.40 as your pH indicator
16 Clinical Examples 65 year old female has a myocardial infarction and also develops respiratory arrest Arterial Blood Gas Results: pH 7.27 PaCO2 50 HCO3 24 What is the acidbase status?
17 Clinical Example 76 year old male with poorly controlled diabetes is reporting signs and symptoms of the 3 P's. In addition, he has a sweet odor to his breath. Arterial Blood Gas Results: pH 7.32 PCO2 32 HCO3 18 What is the acidbase status?
18 Clinical Example
A 29 year old woman has a nasogastric tube attached to low wall suction after having part of her large intestine removed. It is draining green bile like material. Arterial Blood Gas Results: pH 7.49 PCO2 48 HCO3 28 What is the acidbase status?
19 Clinical Example
A patient is admitted to the emergency room with a complaint of chest discomfort and shortness of breath. Respiratory rate is 32. Arterial Blood Gas Results: pH 7.48 PCO2 32 HCO3 23 What is the acid base status?
20 Clinical Example
A patient with renal failure has an ABG drawn soon after they have started dialysis. Arterial Blood Gas Results: pH 7.35 PCO2 33 HCO3 19 What is the acid base status?
21 Treatment of Respiratory Acidosis Hypoventilation R/t Drug Overdose Administer antidoteNarcan Chest trauma Splint chest, assist with ventilations Pulmonary Edema Remove secretions, sit up, oxygen Airway Obstructionremove obstruction COPD Increase breathing efforts through patient teaching Neuromuscular disease assist with ventilation 22 Treatment of Respiratory Alkalosis
Hyperventilation R/t Anxiety Paper bag for breathing and anti anxiety agents High Altitude Administer oxygen treat Pregnancy During labor monitor breathing during rest periods Fever Treat the temperature PE Administer oxygen prepare for intervention
23 Treatment of Metabolic Acidosis
DKA Correct Blood sugar by administering insulin Diarrhea Administer antidiarrheals Renal failure Hold potassium, provide dialysis Shock Treat underlying cause Salicylate Overdose Hold aspirins/NSAIDS 24 Treatment of Metabolic Alkalosis
Loss of gastric Secretions Overuse of antacids Switch antacids d/c or decrease use of Magnessium add Aluminum or calcium based producdt Potassium wasting diuretics Utilize other type of diuretics including loop diuretics (per order) Gastric suctioning Administer IV with 20 mEq of potassium in it (per order) VomitingAntiemetics to stop 25 ...
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- Spring '12
- Homeostasis, Bicarbonate, arterial blood, Arterial blood gas