Arterial blood gas analysis and its interpretation in detail

1. Ms Alisha Talwar

2. Content
• Arterial Blood Gas
• Application of ABG
• Overview
• Basic Physiology in response to ABG
• Acid-Base disorders
• Parameters of ABG
• Components of ABG

3. Content
• Indications of ABG
• Contraindications of ABG
• Arteries to be selected for ABG
• Technical errors
• ABG equipment
• Steps of Procedure for direct sampling
• ABG from Arterial Line

4. Content
• Interpretation of ABG
• Complications

5. Arterial Blood Gas
• Arterial blood gas (ABG) analysis is a common
investigation in emergency departments and ICUs.
• ABG is measured in a laboratory test to determine the
extent of compensation by the buffer system.
• It measures the acidity (pH) and the levels of oxygen and
carbon dioxide in arterial blood.
• Blood sample for ABG analysis is obtained either through
direct arterial puncture or through an indwelling arterial
catheter under aseptic techniques.

6. Applications of ABG
• To document respiratory failure and assess its severity
• To monitor patients on ventilators and assist in weaning
• To assess acid base imbalance in critical illness
• To assess response to therapeutic interventions and
mechanical ventilation

7. Overview
• pH is a measurement of the acidity or alkalinity of the
blood.
• It is inversely proportional to the number of hydrogen ions
(H+) in the blood.
• The more H+ present, the lower the pH will be.
• The pH of a solution is measured on a scale from 1 (very
acidic) to 14 (very alkalotic). A liquid with a pH of 7, such as
water, is neutral (neither acidic nor alkalotic).

9. Contd..
• Changes in body system functions that occur in an acidic
state include
• A decrease in the force of cardiac contractions
• A decrease in the vascular response to catecholamines
• A diminished response to the effects and actions of certain
medications

10. Contd..
• When the pH is above 7.45, the blood is said to be alkalotic.
An alkalotic state interferes with tissue oxygenation and
normal neurological and muscular functioning. Significant
changes in the blood pH above 7.8 or below 6.8 will
interfere with cellular functioning, and if uncorrected, will
lead to death.

11. Basic Physiology
• The ABG provides rapid information on following three
physiologic processes, which maintain the pH homeostasis-
• Alveolar function
• Oxygenation
• Acid-Base balance

12. Alveolar Function
• The maintenance of CO2 level depends on the quantity of
CO2 produced in body and its excretion through alveolar
ventilation.
• It is reflected by PaCO2 i.e. partial pressure of carbon
dioxide in arterial blood

13. Oxygenation
• Oxygenation is the process of oxygen diffusing passively
from alveolus to pulmonary capillary, where it bind to
haemoglobin or dissolves into plasma.
• It is a function of :-
• Cardiopulmonary system
• Various factors like PaO2, FiO2 and SaO2

14. Acid-Base Balance
• Body regulated the acid-base balance by following
mechanisms-
• Buffer response
• Respiratory system
• Renal system

15. Acid Base Balance
• Buffer System reacts immediately.
• The respiratory system responds in minutes and reaches
maximum effectiveness in hours.
• The renal response takes 2-3 days to respond maximally
but the kidneys can maintain balance indefinitely in chronic
imbalances.

16. Buffer System
• A buffer consists of a weakly ionized acid or a base and its
salt.
• Buffers act chemically to change strong acid/ base into
weaker acid/base or to bind acid/base to neutralize their
effect.

17. Buffer Systems
• Carbonic acid-bicarbonate system
• Monohydrate dihydrogen phosphate system
• Intracellular and plasma proteins
• Haemoglobin

18. Carbonic acid-bicarbonate system
HCl + NaH2CO3 NaCl + H2CO3
Strong Strong Salt Weak acid
acid base

19. Monohydrate dihydrogen
phosphate system
HCl + Na2HPO4 NaH2PO4 + NaCl
Strong Weak Weak Salt
acid base acid
NaOH + NaH2PO4 Na2HPO4 + H2O
Strong Salt Weak water
base base

20. Proteins
Some of the amino acids of the proteins contain :-
• Free acid radicals (-COOH): These dissociate into CO2
and H+.
• Basic radicals (-NH3OH): These dissociate into NH3
+ and
OH-. The OH- can combine with an H+ to form H2O.

21. Hemoglobin
• Hemoglobin assists in the regulation of pH by shifting
chloride in and out of RBCs in exchange for bicarbonate.

22. The Respiratory system
• Cellular metabolism causes release of CO2 &
water in the circulation, CO2 enters RBCs and
following reaction occurs :-
CO2 + H20 H2CO3 H+ + HCO3
-

23. Contd..
• As the compensatory mechanism, the respiratory system
alter rate and depth of the respirations through
hyperventilation or hypoventilation.
• During acidosis, hyperventilation occurs and more CO2 is
expelled, less remains with the blood. This leads to less
carbonic acid and less H+.
• During alkalosis, hypoventilation occurs and more CO2
remains in the blood which leads to increased carbonic acid
and more H+.

24. Contd..
• If a respiratory problem is the cause of an acid-base
imbalance such as respiratory failure, the respiratory
system loses its ability to correct pH alteration.
• Activation of the lungs to compensate for an imbalance
starts to occur within 1 to 3 minutes.

25. The Renal System
• Kidneys generate additional bicarbonate and
eliminate excess H+ as compensation for acidosis.
• If the renal system is the cause of acid-base imbalance
such as renal failure, it loses its ability to correct a pH
alteration.
• This system may take from hours to days to correct the
imbalance.
• When the respiratory and renal systems are working
together, they are able to keep the blood pH balanced by
maintaining 1 part acid to 20 parts base.

26. Parameters of ABG
Blood gas values pH, PaCO2 , PaO2
Electrolyte values Na+, K+, Ca2+
, Cl-
Metabolite values Lactate
OximetryValues Hb, SaO2

27. Components of Arterial Blood Gas
• The arterial blood gas provides the following values:
pH
• Measurement of acidity or alkalinity, based on the hydrogen
(H+ ) ions present.
• The normal range is 7.35 to 7.45
• Remember: pH > 7.45 = alkalosis
pH< 7.35 = acidosis

28. PO2
• The partial pressure of oxygen that is dissolved in arterial
blood.
• The normal range is 80 to 100 mm Hg.
SaO2
• The arterial oxygen saturation. The normal range is 95% to
100%.

29. pCO2
• The amount of carbon dioxide dissolved in arterial blood.
• The normal range is 35 to 45 mm Hg.
• Remember: pCO2 >45 = acidosis
pCO2 26 = alkalosis

30. HCO3
• The calculated value of the amount of bicarbonate in the
bloodstream.
• The normal range is 22 to 26 mEq/liter
• Remember: HCO3 > 26 = alkalosis
HCO3 < 22 = acidosis

31. B.E.
• The base excess indicates the amount of excess or
insufficient level of bicarbonate in the system.
• The normal range is -2 to +2 mEq/liter.
• Remember: A negative base excess indicates a base deficit
in the blood.

32. Anion Gap
AG = [Na+
] - [Cl-
+HCO3
-
]
• Elevated anion gap represents metabolic acidosis
• Normal value: 12 ± 4 mEq/L
• Major unmeasured anions
– albumin
– phosphates
– sulfates
– organic anions

33. Increased anion gap
o Diabetic Ketoacidosis
o Chronic Kidney Disease
o Lactic Acidosis
o Alcoholic Ketoacidosis
o Aspirin Poisoning
o Methanol Poisoning
o Ethylene Glycol Poisoning
o Starvation

34. Delta Gap
• The difference between patient’s AG & normal AG
• The coexistence of 2 metabolic acid-base disorders may
be apparent
Delta gap = Anion gap – 12
Delta Gap + HCO3 = 22-26 mEq/l
• If >26, consider additional metabolic alkalosis
• If <22, consider additional non AG metabolic acidosis

35. Indications
• Identification of acid-base disturbances.
• Monitoring of acid-base status, as in patient with diabetic
ketoacidosis (DKA).
• Measurement of the partial pressures of oxygen (PaO2) and
carbon dioxide (PaCO2).
• Assessment of the response to therapeutic interventions
such as mechanical ventilation in a patient with respiratory
failure, insulin in patients with diabetic ketoacidosis.

36. Contraindications
• Absolute – poor collateral circulation / peripheral vascular
disease in the limb / cellulitis surrounding the site /
arteriovenous fistula
• Relative – impaired coagulation
(e.g. anticoagulation therapy / liver disease / low platelets
<50)

37. Arteries to be selected for ABG
• Radial
• Dorsalis Pedis
• Femoral
• Brachial

38. Errors due to ABG
• Excessive Heparin
Ideally : Pre-heparinised ABG syringes
Syringe FLUSHED with 0.5ml 1:1000 Heparin &
emptied
DO NOT LEAVE EXCESSIVE HEPARIN IN THE SYRINGE
Heparin Dilusional effect HCo3 pCo2

39. Contd..
• Risk of alteration of results with
• size of syringe/needle
• vol of sample
• Syringes must have > 50% blood
• Use only 3ml or less syringe
• 25% lower values if 1 ml sample taken in 10 ml
• syringe (0.25 ml heparin in needle)

40. Contd…
Air Bubbles
• pO2 150 mm Hg & pCO2 0 mm Hg
• Contact with AIR BUBBLES
• pO2 & pCO2
• Seal syringe immediately after sampling
Body Temperature
• Affects values of pCO2 and HCO3 only
• ABG Analyser controlled for Normal Body
temperatures

41. Contd..
WBC Counts
• 0.01 ml O2 consumed/dL/min
• Marked increase in high TLC/plt counts : pO2
• Chilling / immediate analysis

42. Contd..
• ABG Syringe must be transported earliest via COLD
CHAIN
Change/10
min
Uniced 370C Iced 40C
pH 0.01 0.001
pCO2 1 mm Hg 0.1 mm Hg
pO2 0.1% 0.01%

43. ABG Equipment
• 3 electrode system that measures three fundamental
variables - pO2, pCO2 and pH
• All others parameters such as HCO3
- computed by software
using standard formulae

44. ABG Electrodes
pH (Sanz Electrode)
• Measures H+ ion concentration of sample against a known
pH in a reference electrode, hence potential difference.
Calibration with solutions of known pH (6.384 to 7.384)
PCO2 (Severinghaus Electrode)
• CO2 reacts with solution to produce H+
• Higher Co2 More H+ higher PCO2 measured

45. Contd..
PO2 (Clark Electrode)
• O2 diffuses across membrane producing an electrical current
measured as PO2

46. Steps of Procedure
• Explain the procedure to the patient
• Perform the Modified Allen’s test
• This test involves the assessment of the arterial supply to
the hand.

47. Modified allen test step-1
Ask the patient to clench their fist

48. Step-2
Apply pressure over both the radial and ulnar
artery to obstruct blood supply to the hand

49. Step-3
Ask the patient to open their hand, which should now appear
blanched (if not you have not completely occluded the arteries
with your fingers)

50. Step-4
Remove pressure from the ulnar artery whilst
maintaining pressure over the radial artery

51. Step-5
If there is adequate blood supply from the ulnar artery,
colour should return to the entire hand within 5-15
seconds

52. Articles required
• Arterial blood gas syringe-1ml
• Needle (23G)
• Alcohol wipe – 70% isopropyl
• Gauze
• Tape
• Lidocaine – with small needle/syringe for administration
• Gloves

53. Local anaesthetic
• The sample is routinely obtained from the radial artery and
it is recognised that that the procedure causes significant
pain for the patient and that this can be markedly reduced
by the use of subcutaneous local anaesthetic.
• The British Thoracic Society recommends the routine use of
local anaesthetic for obtaining ABG samples except in
emergencies, or in unconscious or anaesthetised patients.

54. Preparation
• Position the patient’s arm preferably on a pillow for comfort with
the wrist extended (20-30°)
• Prepare all the equipment in the equipment tray using an
aseptic technique
• Palpate the radial artery on the patient’s non-dominant hand
• Clean the site with an alcohol wipe for 30 seconds and allow to
dry before proceeding
• Wash hands again
• Don gloves

55. Contd..
• Prepare and administer lidocaine subcutaneously over the
planned puncture site
• Allow at least 60 seconds for the local anesthetic to work
• Attach the needle to the ABG syringe, expel the heparin and
pull the syringe plunger to the required fill level.

56. Taking the sample
• Palpate the radial artery with your non-dominant hand’s
index finger around 1cm proximal to the planned puncture
site
• Warn the patient you are going to insert the needle
• Holding the ABG syringe like a dart insert the ABG needle
through the skin at an angle of 45° over the point of
maximal radial artery pulsation
• Advance the needle into the radial artery until you observe
blood flashback into the ABG syringe

57. Contd…
• The syringe should then begin to self-fill in a pulsatile
manner (do not pull back the syringe plunger)
• Once the required amount of blood has been collected remove
the needle and apply immediate firm pressure over the
puncture site with some gauze
• Engage the needle safety guard
• Remove the ABG needle from the syringe and discard safely
into a sharps bin
• Place a cap onto the ABG syringe and label the sample
• Yourself or a colleague should continue to apply firm pressure
for 3-5 minutes to reduce the risk of haematoma formation

58. Contd..
• Place sample on an ice pack in a tray.
• Properly label the sample with patient’s details – UHID, name,
gender, body temperature, F02(I).
• Transport the sample to the Blood Gas Analyzer immediately for
analysis. The best rationale for sending sample is to
reduce error in ABG analysis.
• Uncap the syringe and place the sample in the inlet of Blood Gas
Analyzer and press start.
• Enter the details - Patient’s UHID, name, gender, department,
sample type, body temperature.

59. Contd..
• Remove the syringe when prompted by the Blood Gas Analyzer.
• Close the inlet of the Blood Gas Analyzer.
• Correctly interpret the ABG report (as confirmed by
anaesthetist).
• Discard all the used materials according to biomedical waste
management guidelines.
• Wash hands
• Document the procedure and inform the doctor.

60. ABG from the Arterial Line
Pre-Procedure
• Check the administration set and intra-arterial tubing to ensure
• Tubing remains secure
• No kinks in the tubing
• A continuous infusion of heparinised normal saline is maintained
• Stability of pressure on infusion device (300 mmHg)
• Observe for the signs of Cannula displacement, infection,
impaired circulation of cannulated limb.

61. Cannula displacement
• Swelling
• Fluid leakage
• Bleeding
• Blanching
• Pain
• Discomfort
• Abnormal arterial waveform

62. Infection
• Pain
• Redness
• Swelling
• Pus discharge
• Temperature changes (Warm to touch)

63. Impaired circulation of
cannulated limb
• Blanched colour
• Cyanosis
• Cool limb skin/ extremities
• Sluggish capillary refill
• Decreased pulse distal to the site

64. Articles required
• 0.5 % W/V CHLORHEXIDINE GLUCONATE SOLUTION
• Clean gloves
• Syringe- 1ml, 5ml
• Heparin sodium 1000IU/ml
• Guaze pieces
• Ice-pack
• Tray

65. Steps of Procedure
• Check doctor’s order for arterial blood gas (ABG) sampling and
any special instruction.
• Identify the patient.
• Explain the procedure to the patient.
• Perform hand hygiene
• Assemble all the articles near the patient’s bedside.
• Assess the site for any sign of infection example: pain, redness,
pus discharge, temperature changes, swelling.
• Withhold the collection of blood sample in case of infection.

66. Contd..
• Check the functioning of arterial line by confirming arterial
waveform on the monitor graphic display.
• Check patient’s body temperature.
• Wear clean gloves and follow aseptic technique during the
whole procedure.
• Clean the surface of the rubber stopper of the heparin
sodium vial using a cotton swab moistened with 0.5 %
w/v chlorhexidine gluconate solution.

67. Contd..
• Withdraw heparin sodium (1000 IU/ml) into 1ml syringe to wet the plunger
and fill the dead space in the needle
• Hold the needle in an upright position and expel excess heparin sodium and
air bubbles.
• Remove stopper of the sample port and clean the hub of sample port with
0.5% w/v chlorhexidine gluconate solution and allow it to dry.
• Attach 5 ml/10 ml syringe to the sample port.
• Position the stopcock so that blood flows into the syringe and IV bag port is
closed.
• Aspirate at least 5 ml of blood into a syringe to avoid dilution of sample
with normal saline or heparinised saline.
• Reposition the stopcock handle to close off all ports

68. Contd…
• Disconnect the syringe and keep it in a sterile field.
• Attach 1ml heparinised syringe to the sample port.
• Position the stopcock so that blood flows into the sample syringe and IV bag
port is closed.
• Draw 0.5 ml of blood into the sample syringe.
• Reposition the stopcock handle to close off all the ports and disconnect the
sample syringe.
• Cap the sample syringe.
• Expel air bubbles from the syringe.
• Mix the sample thoroughly by inverting and rolling the syringe between the
palms of the hands.

69. Contd..
• If less than 30 seconds have passed, position the stopcock to open the
sample port and return aspirate into central venous line or arterial
line.
• Ensure that no air bubbles introduce to the system.
• Discard the aspirate, if more than 30 seconds have passed.
• Flush the arterial line with normal saline or heparinised saline thoroughly.
• If necessary, clean the hub of sample port and stopper with 0.5% w/v
chlorhexidine gluconate solution and allow it to dry.
• Replace the stopper to the sample port.
• Confirm that the stopcock port is open to the IV bag solution and intra-
arterial catheter.
• Confirm arterial waveform on the monitor graphic display.

70. Contd..
• Place sample on an ice pack in a tray.
• Properly label the sample with patient’s details – UHID, name,
gender, body temperature, F02(I).
• Transport the sample to the Blood Gas Analyzer immediately for
analysis. The best rationale for sending sample is to
reduce error in ABG analysis.
• Uncap the syringe and place the sample in the inlet of Blood Gas
Analyzer and press start.
• Enter the details - Patient’s UHID, name, gender, department,
sample type, body temperature, F02(I).
• Remove the syringe when prompted by the Blood Gas Analyzer.

71. Contd..
• Close the inlet of the Blood Gas Analyzer.
• Correctly interpret the ABG report (as confirmed by
anaesthetist).
• Discard all the used materials according to biomedical
waste management guidelines.
• Wash hands
• Document the procedure and inform the doctor.

72. Interpretation of ABG

73. Interpretation of ABG
• Steps in ABG analysis using the tic-tac-toe method
• There are eight (8) steps simple steps to interpret ABG
results using the tic-tac-toe technique.

74. Step-1 Memorize the normal
values
 For pH, the normal
range is 7.35 to 7.45
 For PaCO2, the
normal range is 35
to 45
 For HCO3, the
normal range is 22
to 26

75. Step-2 Create your tic-tac-toe
grid

76. Step-3 Determine if pH is under
normal, acidosis, or alkalosis
Remember in step #1 that the normal pH range is from 7.35 to 7.45.
• If the blood pH is between 7.35 to 7.39, the interpretation is NORMAL
but SLIGHTLY ACIDOSIS, place it under the NORMAL column.
• If the blood pH is between 7.41 to 7.45, interpretation is NORMAL but
SLIGHTLY ALKALOSIS, place it under the NORMAL column.
• Any blood pH below 7.35 (7.34, 7.33, 7.32, and so on…) is ACIDOSIS,
place it under the ACIDOSIS column.
• Any blood pH above 7.45 (7.46, 7.47, 7.48, and so on…) is
ALKALOSIS, place it under the ALKALOSIS column.

78. Step-4 Determine if paco2 is under
normal, acidosis, or alkalosis

79. Contd..
Remember that the normal range for PaCO2 is from 35 to 45:
• If PaCO2 is below 35, place it under the ALKALOSIS column.
• If PaCO2 is above 45, place it under the ACIDOSIS column.
• If PaCO2 is within its normal range, place it under the
NORMAL column.

80. Step-5 Determine if HCO3 is under
normal, acidosis, or alkalosis

81. Contd…
Remember that the normal range for HCO3 is from 22 to 26:
• If HCO3 is below 22, place it under the ACIDOSIS column.
• If HCO3 is above 26, place it under the ALKALOSIS column.
• If HCO3 is within its normal range, place it under the
NORMAL column.

82. Step-6 Solve for goal #1:
ACIDOSIS or ALKALOSIS

83. • If pH is under the ACIDOSIS column, it is ACIDOSIS.
• If pH is under the ALKALOSIS column, it is ALKALOSIS.
• If pH is under the NORMAL column, determine whether the
value is leaning towards ACIDOSIS or ALKALOSIS and
interpret accordingly.

84. Step-7 Solve for goal #2:
METABOLIC or RESPIRATORY

85. • If pH is under the same column as PaCO2, it is
RESPIRATORY.
• If pH is under the same column as HCO3, it is METABOLIC.
• If pH is under the NORMAL column, determine whether the
value is leaning towards ACIDOSIS or ALKALOSIS and
interpret accordingly.

86. Step-8 Solve for goal #3:
COMPENSATION

87. • It is FULLY COMPENSATED if pH is normal.
• It is PARTIALLY COMPENSATED if all three (3) values are
abnormal.
• It is UNCOMPENSATED if PaCO2 or HCO3 is normal and the
other is abnormal.

90. Respiratory Acidosis
• Respiratory acidosis is defined as a pH less than 7.35 with a
PaCO2 greater than 45 mm Hg.
• Acidosis is caused by an accumulation of CO2 which
combines with water in the body to produce carbonic acid,
thus, lowering the pH of the blood.
• Any condition that results in hypoventilation can cause
respiratory acidosis.

91. Respiratory Acidosis causes
• Central nervous system depression related to head injury
• Central nervous system depression related to medications such
as narcotics, sedatives, or anesthesia
• Impaired respiratory muscle function related to spinal cord
injury, neuromuscular diseases, or neuromuscular blocking drugs
• Pulmonary disorders such as atelectasis, pneumonia,
pneumothorax, pulmonary edema, or bronchial obstruction
• Massive pulmonary embolus
• Hypoventilation due to pain, chest wall injury/deformity, or
abdominal distension

93. Management
• Increasing ventilation will correct respiratory acidosis.
• The method for achieving this will vary with the cause of
hypoventilation. If the patient is unstable, manual
ventilation with a bagmask is indicated until the underlying
problem can be addressed.
• After stabilization, rapidly resolvable causes are addressed
immediately.

94. Respiratory alkalosis
• Respiratory alkalosis is defined as a pH greater than 7.45
with a PaCO2 less than 35 mm Hg.
• Any condition that causes hyperventilation can result in
respiratory alkalosis.

95. Respiratory alkalosis causes
These conditions include:
• Psychological responses, such as anxiety or fear
• Pain
• Increased metabolic demands, such as fever, sepsis,
pregnancy, or thyrotoxicosis
• Medications, such as respiratory stimulants
• Central nervous system lesions

97. Metabolic Acidosis
• Metabolic acidosis is defined as a bicarbonate level of less
than 22 mEq/L with a pH of less than 7.35.
• Metabolic acidosis is caused by either a deficit of base in
the bloodstream or an excess of acids, other than CO2.
• Diarrhea and intestinal fistulas may cause decreased levels
of base

98. Metabolic Acidosis causes
Causes of increased acids include:
• Renal failure
• Diabetic ketoacidosis
• Anaerobic metabolism
• Starvation
• Salicylate intoxication

100. Management
• The only appropriate way to treat this source of acidosis is to
restore tissue perfusion to the hypoxic tissues.
• Other causes of metabolic acidosis should be considered after
the possibility of tissue hypoxia has been addressed.
• Current research has shown that the use of sodium
bicarbonate is indicated only for known bicarbonate-
responsive acidosis, such as that seen with renal failure.
• Routine use of sodium bicarbonate to treat metabolic
acidosis results in subsequent metabolic alkalosis with
hypernatremia and should be avoided.

101. Metabolic Alkalosis
• Metabolic alkalosis is defined as a bicarbonate level greater
than 26 mEq/liter with a pH greater than 7.45.
• Either an excess of base or a loss of acid within the body
can cause metabolic alkalosis.

102. Metabolic Alkalosis causes
Excess base occurs from
• Ingestion of antacids
• excess use of bicarbonate
• use of lactate in dialysis
• Loss of acids can occur secondary to protracted vomiting,
gastric suction, hypochloremia, excess administration of
diuretics, or high levels of aldosterone.

104. Management
• Metabolic alkalosis is one of the most difficult acid-base
imbalances to treat.
• Bicarbonate excretion through the kidneys can be
stimulated with drugs such as acetazolamide (Diamox®),
but resolution of the imbalance will be slow. In severe
cases, IV administration of acids may be used.
• CLINICAL APPLICATION: It is significant to note
that metabolic alkalosis in hospitalized patients is
usually iatrogenic in nature.

105. Mixed Acid-base disorders
• Presence of more than one acid-base disorder
simultaneously
• Clues to a mixed disorder
• Normal pH with abnormal HCO3 or pCO2
• HCO3 or pCO2 move in opposite directions
• pH changes in opposite direction is known for primary
disorder

106. Complications
• Hemorrhage
• Thrombosis
• Air embolism
• Arteriospasm
• Infection/sepsis

107. Conclusion
• ABG plays a pivotal role in making correct diagnosis and
deciding management strategies in high-risk patients as
well as in the care of critically ill patients.
• Understanding the interpretation of arterial blood gases
helps ensure that the nurse respond to critical acid-base
imbalances and provide appropriate interventions.

108. References
• Arterial blood gases. (2017). Retrieved August 20, 2017, from
https://www.uptodate.com/contents/arterial-blood-gases
• WHO guidelines on drawing blood: best practices in phlebotomy.
Published 2010.
• Bowers, B., (2009). Arterial Blood Gas Analysis: An Easy
Learning Guide. Primary Health Care, 19 (7), 11.
• Coggon, J.M. (2008). Arterial blood gas analysis 1:
understanding ABG reports. Nursing Times, 104 (18), 28-9.
• Coggon, J.M.(2008). Arterial blood gas analysis: 2:
compensatory mechanisms. Nursing Times, 104 (19), 24-5.

109. Contd…
• Dunford, F. (2009). Book reviews. Arterial blood gas analysis: an easy
learning guide. New Zealand Journal of Physiotherapy, 37 (2), 97.
• Greaney, B. (2008). Book mark. Arterial blood gas analysis: an easy
learning guide. Emergency Nurse, 16 (7), 6.
• Lawes, R. (2009). Body out of balance: understanding metabolic
acidosis and alkalosis. Nursing, 39 (11), 50-4.
• Lynch, F. (2009). Arterial blood gas analysis: implications for nursing.
Paediatric Nursing, 21 (1), 41-4.
• Palange, P., Ferrazza, A.M.(2009). A simplified approach to the
interpretation of arterial blood gas analysis. Breathe, 6 (1), 15-22 .