NURSES ROLE IN ARTERIAL PUNCTURE AND ABG ANALYSIS

STEPHY STANLY

Acid base status

Degree of oxygenation of blood and adequacy of alveolar ventilation

Continous arterial blood pressure monitoring in an emergency

Purposes

1ml or 2 ml disposable syringe 20 gauge disposable needles Heparin1;1000 Alcohol swab disposable gloves Arterial catheter for continous pressure

monitoring Tegaderm

Articles

Identify patient by name and explain procedure

Temperature

Heparinize 2 ml syringe

Wash hands wear gloves

Palpate the radial,brachial or femoral artery

Procedure

perform allen test

palpate for maximum pulsation

at 45-60 degreee angle

once the artery is punctured ,arterial pressure will push up the piston of the syringe and a pulsating flow of blood will fill the syringe.

apply firm pressure -for 5 mins.

air is removed and cap the syringe needle and keep it in a container of ice.

Arterial blood gas analysis is an essential part of diagnosing and

managing a patient’s oxygenation status and acid-base balance

ABG ANALYSIS

pH = Pka + log base/acid

Acidemia – H+ conc in plasma is greater than normal

Alkalemia – H + conc in plasma is less than normal

Buffer

Excess heparin : low pH, PCO2 & HCO3

Contamination with room air : PaO2, pH, PaCO2

Delayed analysis : By 10 mts – pH decreases by 0.01 PCO2 increases by 1 mmHg O2 conc decreases by 0.001

 

ABG ERRORS

Normal PH : 7.35 – 7.45 acidosis < 7.35 alkalosis > 7.45

STEP 1 - ASESS PH

Normal PaCO2- 35-45

High PaCO2 > 45 PH low Resp acidosis

Low PaCO2 < 35 PH high Resp alkalosis

STEP 2 – ASSESS PaCO2

Normal HCO3 – 22-28 meq/L

PH low HCO3 low Metabolic acidosis

PH high HCO3 high Metabolic alkalosis

STEP 3 – HCO3

Determine if there is a compensatory, mechanism working to try to correct the pH. Values of HCO3 and CO2

Step 4:

Analyse the partial pressure of oxygen and saturation

Step 5

Normal Values(At sea level)

Range:

pH 7.35--‐7.45

pCO2 35--‐45mmHg

pO2 80--‐100mmHg

O2Saturation 95--‐100%

HCO3

Base Excess

22--‐26mEq/L

+or--‐2

ABG's:  pH 7.31   PCO2 55 mm Hg   HCO3

- 28 mEq/L

Qiuz 1

Ans

uncompensated respiratory acidosis

ABG's:  pH 7.31   PCO2 55 mm Hg   HCO3- 35 mEq/L

Compensated respiratory acidosis

Ph- 7.30 Pco2 -30 Po2-68 O2 sat- 92% HCO3-14

Compensated metabolic acidosis

Ph -7.18 Pco2 44 Po2-92 O2 sat-95% Hco3-16

Uncompensated metabolic aciosis

Ph- 7.27 Pco2-53 Po2-50 O2 sat-79% HCO3-24

Uncompensated respiratory acidosis with hypoxemia