ABG ANALYSIS AND INTERPRETATION .pptx

abg

1. BASICS IN ABG ANALYSIS AND INTERPRETATION DR.S.RAMACHANDRAN MPT, ( Ph.D ) PROFESSOR FACULTY OF PHYSIOTHERAPY ACS MEDICAL COLLEGE AND HOSPITAL CHENNAI – 600 077.

2. synopsis Definition Indication ABG component Normal values Sites for obtaining ABG Complication A look at acids and bases Acid base disorders Respiratory acidosis Case - A Case –B Case - C Case – D Reference

3. DEFINITION It is a diagnostic procedure in which blood is obtained from an artery directly by an arterial puncture or accessed by a way of indwelling arterial catheter.

4. I N DI C A T I O N To obtain information about patient ventilation (PCO2) , oxygenation (PO2) and acid base balance Monitor gas exchange and acid base abnormalities for patient on mechanical ventilator or not To evaluate response to clinical intervention and diagnostic evaluation ( oxygen therapy ) An ABG test may be most useful when a person's breathing rate is increased or decreased or when the person has very high blood sugar levels, a severe infection, or heart failure.

5. A B G C O M PO NE N T PH: Measures hydrogen ion concentration in the blood, it shows blood’s acidity or alkalinity. PCO2 : It is the partial pressure of CO2 that is carried by the blood for excretion by the lungs, known as respiratory parameter. PO2: It is the partial pressure of O2 that is dissolved in the blood , it reflects the body ability to pick up oxygen from the lungs. HCO3 : Known as the metabolic parameter, it reflects the kidney’s ability to retain and excrete bicarbonate. Helps pH of blood from becoming too acidic or too basic .

6. N O R M AL V A L U E S P H = 7.35 – 7.45 Pco2= 35-45mmHg Po2 = 80-100mHg HCO3=22-26 meq /L

7. SIT E S F O R O B T AI N I NG A B G Radial artery ( most common ) Brachial artery Femoral artery R a dial is t h e most p refer a ble s ite used because: It is easy to access It is not a deep artery which facilitate palpation, stabilization and puncturing The artery has a collateral blood circulation

8. SIT E S F O R O B T AI N I NG A B G

9. C O M P L I C A TI O N Arteriospasm Hematoma Hemorrhage Distal ischemia Infection Numbness

10. A L O O K A T ACID S A N D B A SE S The body constantly works to maintain a balance (homeostasis) between acids and bases. Without that balance, cells can’t function properly. As cells use nutrient to produce the energy, two by- products are formed H+ & CO2. acid-base balance depends on the regulation of the free hydrogen ions Even slight imbalance can affect metabolism and essential body functions. Several conditions as infection or trauma and medications can affect acid-base balance .

11. ACID BASE DISORDERS

12. Respiratory acidosis occurs when too much CO2 builds up in the body. Normally, the lungs remove CO2 while exhaling. This may happen due to: • Chronic airway conditions, like asthma • Injury to the chest • Obesity, which can make breathing difficult • Sedative misuse • Muscle weakness in the chest • Problems with the nervous system • Deformed chest structure RESPIRATORY ACIDOSIS

13. Respiratory alkalosis occurs when there isn’t enough carbon dioxide in the bloodstream. It’s often caused by: hyperventilation, which commonly occurs with anxiety high fever lack of oxygen salicylate poisoning liver disease lung disease RESPIRATORY ALKALOSIS

14. Metabolic alkalosis develops when body loses too much acid or gains too much base. This can be attributed to: Excess vomiting, which causes electrolyte loss Overuse of diuretics A large loss of potassium or sodium in a short amount of time Antacids Accidental ingestion of bicarbonate, which can be found in baking soda Laxatives Alcohol abuse. METABOLIC ALKALOSIS

15. Metabolic acidosis : starts in the kidneys instead of the lungs. It occurs when they can’t eliminate enough acid or when they get rid of too much base. Diabetic acidosis occurs in people with diabetes that’s poorly controlled. When body lacks enough insulin, ketone build up in the body and acidify blood. • Hyperchloremic acidosis results from a loss of sodium bicarbonate. This base helps to keep the blood neutral. Both diarrhea and vomiting can cause this type of acidosis. • Lactic acidosis occurs when there’s too much lactic acid in body. Causes can include chronic alcohol use, cancer, seizures, liver failure, prolonged lack of oxygen, and low blood sugar. • Renal tubular acidosis occurs when the kidneys are unable to excrete acids into the urine.

16. CASE- A PH - 7.10 Paco2- 40 mmHg Hco3- 16 meq /L DIAGNOSIS…….? CASE -B PH – 7.65 Paco2- 40 mmHg Hco3- 32 meq /L DIAGNOSIS……? CASE - C PH – 7.11 Paco2- 50 mmHg Hco3- 24 meq /L DIAGNOSIS……? CASE -D PH – 7.58 Paco2- 25 mmHg Hco3- 23 meq /L DIAGNOSIS……?

17. REFERENCE Cash’s textbook of chest, vascular disorders for physiotherpists - Patricia A. Downie Textbook of physiotherapy for cardio respiratory ,cardiac surgery and thoracic surgery condition - G B Madhuri . Textbook of Clinical medicine - Clark and Praveenkumar