This is a slide presentation of ABG assessment in physical therapy in cardiovascular diseases.

1. ARTERIAL BLOOD GAS:
an indicator of physical endurance
post-cardiac surgery?
Reza Nejat, M. D., FCCM,
Anesthesiology and Critical Care Dept., Laleh Hospital,
Anti-Doping, Nutrition and Metabolism Consultant, World Powerlifting Ltd.,
Eurasia Division (Asia, Iran), Melbourne, Australia,
Former Assistant Professor, SBMU,

2. ABG: an indicator of
physical endurance
post-cardiac surgery?
Circulation, vol. XXIX,
March 1964
by: Reza Nejat, M. D., FCCM; Anti‐Doping, Nutrition,
Metabolism Consultant

3. ABG: an indicator of
physical endurance
post-cardiac surgery?
• WHO definition of Cardiac Rehab:
• the activities required to influence:
• the underlying cause of the disease,
• the best possible physical, mental,
and social conditions:
• so that the patient may, by their own
efforts, preserve or resume, as normal a
place as possible in the society.
• Rehabilitation:
• not an isolated form of therapy,
• must be integrated within the entire
treatment.
Cardiac Rehabilitation is an
interdisciplinary team
approach to patients with
functional limitations
secondary to heart disease.
by: Reza Nejat, M. D., FCCM; Anti‐Doping, Nutrition,
Metabolism Consultant

4. ABG: an indicator of
physical endurance
post-cardiac surgery?
WHO definition of Cardiac Rehab:
the activities required to influence:
the underlying cause of the disease,
the best possible physical, mental, and
social conditions:
so that the patient may, by their own efforts,
preserve or resume, as normal a place as
possible in the society.
by: Reza Nejat, M. D., FCCM; Anti‐Doping, Nutrition,
Metabolism Consultant

5. ABG: an indicator of
physical endurance
post-cardiac surgery?
• Early Rehabilitation Exercise
post-CABG: (2015 and 2022 studies)
improve
• cardiopulmonary function;
higher FEV1
• exercise tolerance;
• the quality of life;
• Higher LVEF
• Lower LVES and LVED
Dimensions
• Higher 6MWT, 𝑉𝑂 𝑚𝑎𝑥 and
anaerobic threshold
by: Reza Nejat, M. D., FCCM; Anti‐Doping, Nutrition,
Metabolism Consultant

6. ABG: an indicator of
physical endurance
post-cardiac surgery?
• What happens to the muscles in
CR?
• Increased:
A. number and size of
mitochondria
B. oxidative enzyme activity
C. capillarizations
D. myoglobin
improve
 cardiopulmonary function; higher
FEV1
 exercise tolerance;
 the quality of life;
Higher LVEF
Lower LVES and LVED Dimensions
Higher 6MWT, 𝑉𝑂 𝑚𝑎𝑥 and anaerobic
threshold
by: Reza Nejat, M. D., FCCM; Anti‐Doping, Nutrition,
Metabolism Consultant

7. ABG: an indicator of
physical endurance
post-cardiac surgery?
In patients with CVD:
Repeated submaximal daily
activities with less physiological
stress:
1) Decreased heart rate
2) Decreased blood pressure
3) Decreased plasma catecholamine
concentrations
What happens to the muscles in CR?
Increased:
A. number and size of
mitochondria
B. oxidative enzyme activity
C. capillarizations
D. myoglobin
by: Reza Nejat, M. D., FCCM; Anti‐Doping, Nutrition,
Metabolism Consultant

8. ABG: an indicator of
physical endurance
post-cardiac surgery?
• Medical assessment:
• evaluating physical abilities, limitations
and risk factors;
• Physical activity:
• exercises to improve cardiovascular
and muscular fitness;
• Lifestyle education:
• expert advice about diet and nutrition;
• Psychosocial support:
• decrease anxiety and increase
knowledge
In patients with CVD:
Repeated submaximal daily
activities with less physiological stress:
1) Decreased heart rate,
2) Decreased blood pressure
3) Decreased plasma
catecholamine concentrations
by: Reza Nejat, M. D., FCCM; Anti‐Doping, Nutrition,
Metabolism Consultant

9. ABG: an indicator of
physical endurance
post-cardiac surgery?
• Be careful! stop training in case of:
1) Symptomatic hypotension
2) Tachycardia, palpitation
3) Arrhythmias
4) Breathlessness, lethargy, dizziness
5) Unstable heart failure, weight gain >2kg in
2 days
6) Unstable/uncontrolled diabetes
7) Unresolved/unstable angina
8) Blood pressure systolic > 200 mmHg and
diastolic > 110 mmHg
Medical assessment:
evaluating physical
abilities, limitations
and risk factors;
by: Reza Nejat, M. D., FCCM; Anti‐Doping, Nutrition,
Metabolism Consultant

10. ABG: an indicator of
physical endurance
post-cardiac surgery?
• Cell Metabolism (aerobic or anaerobic)
• 𝑉𝑂 𝑡ℎ𝑒 𝑎𝑚𝑜𝑢𝑛𝑡 𝑜𝑓 𝑂 𝑐𝑜𝑛𝑠𝑢𝑚𝑒𝑑 𝑖𝑛 𝑡ℎ𝑒 𝑢𝑛𝑖𝑡 𝑜𝑓 𝑡𝑖𝑚𝑒
• The thing that should be provided
• 𝑉𝐶𝑂 𝑡ℎ𝑒 𝑎𝑚𝑜𝑢𝑛𝑡 𝑜𝑓 𝐶𝑂 𝑝𝑟𝑜𝑑𝑢𝑐𝑒𝑑 𝑖𝑛 𝑡ℎ𝑒 𝑢𝑛𝑖𝑡 𝑜𝑓 𝑡𝑖𝑚𝑒
• The thing that should be eliminated
• 𝑪𝒏 𝑯𝟐𝑶 𝒏 𝒏𝑶𝟐 → 𝒏𝑪𝑶𝟐 𝒏𝑯𝟐𝑶
• 𝑪𝟔 𝑯𝟐𝑶 𝟔
𝒈𝒍𝒚𝒄𝒐𝒍𝒚𝒔𝒊𝒔→𝑯
𝟐𝑨𝑻𝑷𝒔
• 𝑪𝟔 𝑯𝟐𝑶 𝟔
𝑬𝑻𝑪@𝒎𝒊𝒕𝒐𝒄𝒉𝒐𝒏𝒅𝒓𝒊𝒂 𝑶𝟐 𝒂𝒗𝒂𝒊𝒍𝒂𝒃𝒍𝒆
𝟑𝟔𝑨𝑻𝑷𝒔
Debt of 𝑶𝟐→ Base Excess (BE)
‐2↔+2 (meq/L) normal
‐3‒‐5 mild
‐6‒‐9 moderate
<‐10 severe
by: Reza Nejat, M. D., FCCM; Anti‐Doping, Nutrition,
Metabolism Consultant

11. ABG: an indicator of
physical endurance
post-cardiac surgery?
•ABG
♣ Described in 19th century
♣ CLINICAL USE originated
from the poliomyelitis epidemic
in the early 1950s
• Accurate and timely
interpretation of ABG and an
acid–base disorder can be
lifesaving,
Medical Assessment:
by: Reza Nejat, M. D., FCCM; Anti‐Doping, Nutrition,
Metabolism Consultant

12. ABG: an indicator of
physical endurance
post-cardiac surgery?
• ABG analysis: The parameters
commonly measured:
• pH;
• PCO2;
• PO2;
• Hemoglobin (Hb);
• COHb (carboxyhemoglobin);
• MetHb (methemoglobin);
• lactate;
• glucose;
• electrolytes (sodium, potassium,
and chloride);
HCO3 and BE are calculated**
ACID: proton donor,
Lactic acid, 𝑪𝑶𝟐 (lung)
Acidemia: pH<7.35 or 𝑯 ↑↑
Acidosis: consequences of Acidemia
BASE: proton acceptor,
Lactate, 𝑯𝑪𝑶𝟑 (kidney)
Alkalemia: pH>7.45 or 𝑯 ↓↓
Alkalosis: consequences of Alkalemia
𝒑𝑯 𝒍𝒐𝒈𝟏𝟎 𝑯
by: Reza Nejat, M. D., FCCM; Anti‐Doping, Nutrition,
Metabolism Consultant

13. ABG: an indicator of
physical endurance
post-cardiac surgery?
• 𝑷𝒂𝑪𝑶𝟐
𝑽𝑪𝑶𝟐
𝑽𝑨
• 𝒑𝑯 𝒑𝑲 𝒍𝒐𝒈𝟏𝟎
𝑯𝑪𝑶𝟑
𝜶𝑪𝑶𝟐
𝑷𝑪𝑶𝟐
• 𝑷𝒂𝑶𝟐 𝑭𝒊𝑶𝟐 𝟓
ABG analysis:
 ventilation
 acid-base
 oxygenation
by: Reza Nejat, M. D., FCCM; Anti‐Doping, Nutrition,
Metabolism Consultant

14. ABG: an indicator of
physical endurance
post-cardiac surgery?
• Cell Metabolism (aerobic or anaerobic)
• 𝑉𝑂 𝑡ℎ𝑒 𝑎𝑚𝑜𝑢𝑛𝑡 𝑜𝑓 𝑂 𝑐𝑜𝑛𝑠𝑢𝑚𝑒𝑑 𝑖𝑛 𝑡ℎ𝑒 𝑢𝑛𝑖𝑡 𝑜𝑓 𝑡𝑖𝑚𝑒
• The thing that should be provided
• 𝑉𝐶𝑂 𝑡ℎ𝑒 𝑎𝑚𝑜𝑢𝑛𝑡 𝑜𝑓 𝐶𝑂 𝑝𝑟𝑜𝑑𝑢𝑐𝑒𝑑 𝑖𝑛 𝑡ℎ𝑒 𝑢𝑛𝑖𝑡 𝑜𝑓 𝑡𝑖𝑚𝑒
• The thing that should be eliminated
• 𝑪𝒏 𝑯𝟐𝑶 𝒏 𝒏𝑶𝟐 → 𝒏𝑪𝑶𝟐 𝒏𝑯𝟐𝑶
• 𝑪𝟔 𝑯𝟐𝑶 𝟔
𝒈𝒍𝒚𝒄𝒐𝒍𝒚𝒔𝒊𝒔→𝑯
𝟐𝑨𝑻𝑷𝒔
• 𝑪𝟔 𝑯𝟐𝑶 𝟔
𝑬𝑻𝑪@𝒎𝒊𝒕𝒐𝒄𝒉𝒐𝒏𝒅𝒓𝒊𝒂 𝑶𝟐 𝒂𝒗𝒂𝒊𝒍𝒂𝒃𝒍𝒆
𝟑𝟔𝑨𝑻𝑷𝒔
by: Reza Nejat, M. D., FCCM; Anti‐Doping, Nutrition,
Metabolism Consultant

15. ABG: an indicator of
physical endurance
post-cardiac surgery?
Clinical Features
Hypoxemia and Hypercapnia
by: Reza Nejat, M. D., FCCM; Anti‐Doping, Nutrition,
Metabolism Consultant
Hypoxemia hypercapnia
Cyanosis Flapping tremor of hands
Tachypnea Tachypnea
Tachycardia→arrhythmia→bradycardia Tachycardia
Peripheral vasoconstriction Peripheral vasodilation
warm hands/ headache
Restlessness→confusion→coma drowsiness→hallucina on→coma
Sweating

16. ABG: an indicator of
physical endurance
post-cardiac surgery?
• 𝒂 𝟐
• Memory defect, impaired judgement
• 𝒂 𝟐
• Tissue damage
• 𝒂 𝟐
• Unconsciousness
• 𝒂 𝟐
• Death
In normal subjects:
𝑷𝒂𝑶𝟐 𝑭𝒊𝑶𝟐 𝟓𝟎𝟎
𝑷𝒂𝑶𝟐/𝑭𝒊𝑶𝟐
𝑵𝒐𝒓𝒎𝒂𝒍: 𝟏𝟎𝟎/𝟎. 𝟐𝟏 𝟓𝟎𝟎
MILD ARDS
200< 𝑷𝒂𝑶𝟐/𝑭𝒊𝑶𝟐<300
MODERATE ARDS
100< 𝑷𝒂𝑶𝟐/𝑭𝒊𝑶𝟐<200
SEVERE ARDS
𝑷𝒂𝑶𝟐/𝑭𝒊𝑶𝟐<100
(on PEEP=5cmH2O)
by: Reza Nejat, M. D., FCCM; Anti‐Doping, Nutrition,
Metabolism Consultant

17. ABG: an indicator of
physical endurance
post-cardiac surgery? • SpO2/FiO2=235
• PaO2/FiO2=200
Moderate ARDS:
PaO2/FiO2<200
• SpO2/FiO2=315
• PaO2/FiO2=300
Mild ARDS:
PaO2/FiO2<300
𝑷𝒂𝑶𝟐/𝑭𝒊𝑶𝟐
𝑵𝒐𝒓𝒎𝒂𝒍: 𝟏𝟎𝟎/𝟎. 𝟐𝟏 𝟓𝟎𝟎
MILD ARDS
200< 𝑷𝒂𝑶𝟐/𝑭𝒊𝑶𝟐<300
MODERATE ARDS
100< 𝑷𝒂𝑶𝟐/𝑭𝒊𝑶𝟐<200
SEVERE ARDS
𝑷𝒂𝑶𝟐/𝑭𝒊𝑶𝟐<100
(on PEEP=5cmH2O)
by: Reza Nejat, M. D., FCCM; Anti‐Doping, Nutrition,
Metabolism Consultant

18. ABG: an indicator of
physical endurance
post-cardiac surgery?
• increased CO2 directly increases
respiratory sinus arrhythmia
magnitude, in the absence of any
change in 𝑉 and 𝐹 (2001 study)
𝑷𝒂𝑪𝑶𝟐
𝑽𝑪𝑶𝟐
𝑽𝑨
𝑽𝑨 𝑽𝑻 𝑽𝑫 𝑭𝑩
by: Reza Nejat, M. D., FCCM; Anti‐Doping, Nutrition,
Metabolism Consultant

19. ABG: an indicator of
physical endurance
post-cardiac surgery?
Veno-Arterial 𝐶𝑂 Gap:
𝐓𝑪𝑶𝟐 𝒅𝒊𝒔𝒔𝒐𝒍𝒗𝒆𝒅 𝑪𝑶𝟐 𝑯𝑪𝑶𝟑 𝑹 𝑵𝑯𝟐 𝑪𝑶𝟐
Venous 𝐓𝑪𝑶𝟐⎻ Arterial 𝐓𝑪𝑶𝟐≈ 𝟒𝟓 𝒎𝒍/𝒍
by: Reza Nejat, M. D., FCCM; Anti‐Doping, Nutrition,
Metabolism Consultant

20. ABG: an indicator of
physical endurance
post-cardiac surgery?
• ABG analysis: The parameters
commonly measured:
• pH;
• PCO2;
• PO2;
• Hemoglobin (Hb);
• COHb (carboxyhemoglobin);
• MetHb (methemoglobin);
• lactate;
• glucose;
• electrolytes (sodium, potassium,
and chloride);
HCO3 and BE are calculated**
ACID: proton donor,
Lactic acid, 𝑪𝑶𝟐 (lung)
Acidemia: pH<7.35 or 𝑯 ↑↑
Acidosis: consequences of Acidemia
BASE: proton acceptor,
Lactate, 𝑯𝑪𝑶𝟑 (kidney)
Alkalemia: pH>7.45 or 𝑯 ↓↓
Alkalosis: consequences of Alkalemia
𝒑𝑯 𝒍𝒐𝒈𝟏𝟎 𝑯
by: Reza Nejat, M. D., FCCM; Anti‐Doping, Nutrition,
Metabolism Consultant

21. ABG: an indicator of
physical endurance
post-cardiac surgery?
Consequences of
acid-base
dyshomeostasis
Accurate and timely
interpretation of ABG and
an acid–base disorder can be
lifesaving,
by: Reza Nejat, M. D., FCCM; Anti‐Doping, Nutrition,
Metabolism Consultant
• Acidosis:
• decreased cardiac
contractility;
• Increases HPV, MPAP, PVR;
• muscle wasting;
• pH sensitivity of:
• many essential cellular
processes,
• metabolic enzymes,
• transmembrane transport
processes

22. ABG: an indicator of
physical endurance
post-cardiac surgery?
Consequences of
acid-base
dyshomeostasis
Accurate and timely
interpretation of ABG and
an acid–base disorder can be
lifesaving,
by: Reza Nejat, M. D., FCCM; Anti‐Doping, Nutrition,
Metabolism Consultant
• Alkalosis:
• muscle hyper-excitability and
twisting,
• hypokalemia,
• hypocalcemia,
• dysrrhythmia,
• altered mental status,
• pH sensitivity of:
• many essential cellular
processes,
• glycolysis,
• transmembrane transport
processes

23. ABG: an indicator of
physical endurance
post-cardiac surgery?
• Buffering system minimizes pH
Changes:
• Substantial portion of buffering:
• Bone and proteins
• Most important buffering system:
• 𝐻𝐶𝑂 /𝐶𝑂 system
Accurate and timely interpretation of ABG and an
acid–base disorder can be lifesaving,
𝒑𝑯 𝒑𝑲 𝒍𝒐𝒈𝟏𝟎
𝑯𝑪𝑶𝟑 𝒎𝒆𝒕𝒂𝒃𝒐𝒍𝒊𝒄, 𝒌𝒊𝒅𝒏𝒆𝒚
𝟎. 𝟎𝟑 𝑷𝑪𝑶𝟐
𝒓𝒆𝒔𝒑𝒊𝒓𝒂𝒕𝒐𝒓𝒚, 𝒍𝒖𝒏𝒈
by: Reza Nejat, M. D., FCCM; Anti‐Doping, Nutrition,
Metabolism Consultant

24. ABG: an indicator of
physical endurance
post-cardiac surgery?
• Acid-Base Homeostasis:
• depends on compensation for
a primary disturbance.
• Compensation:
• for a respiratory disturbance is
metabolic,
• for a metabolic disturbance is
respiratory.
Substantial portion of buffering:
Bone and proteins
Most important buffering system:
𝑯𝑪𝑶𝟑 𝑯 ↔ 𝑯𝟐𝑪𝑶𝟑 ↔ 𝑪𝑶𝟐 𝑯𝟐𝑶
𝒑𝑯 𝒑𝑲 𝒍𝒐𝒈𝟏𝟎
𝑯𝑪𝑶𝟑 𝒎𝒆𝒕𝒂𝒃𝒐𝒍𝒊𝒄, 𝒌𝒊𝒅𝒏𝒆𝒚
𝟎. 𝟎𝟑 𝑷𝑪𝑶𝟐
𝒓𝒆𝒔𝒑𝒊𝒓𝒂𝒕𝒐𝒓𝒚, 𝒍𝒖𝒏𝒈
by: Reza Nejat, M. D., FCCM; Anti‐Doping, Nutrition,
Metabolism Consultant

25. ABG: an indicator of
physical endurance
post-cardiac surgery?
Acid-Base Homeostasis:
depends on compensation for
a primary disturbance.
Compensation:
for a respiratory disturbance is
metabolic,
for a metabolic disturbance is
respiratory.
by: Reza Nejat, M. D., FCCM; Anti‐Doping, Nutrition,
Metabolism Consultant

26. ABG: an indicator of
physical endurance
post-cardiac surgery?
• Assessment of ABG
1. careful clinical evaluation
2. determine the primary acid–base
disorder
3. consider the metabolic component
4. consider the possibility of a mixed
metabolic acid–base disturbance
5. determine the anion gap
6. note the serum osmolal gap in any
patient with an unexplained high
anion‐gap acidosis
7. evaluate the respiratory component
8. determine the cause of the identified
processes
ACID: proton donor,
Acidemia: pH<7.35 or 𝑯 ↑↑
BASE: proton acceptor,
Alkalemia: pH>7.45 or 𝑯 ↓↓
by: Reza Nejat, M. D., FCCM; Anti‐Doping, Nutrition,
Metabolism Consultant

27. ABG: an indicator of
physical endurance
post-cardiac surgery?
• Metabolic acidosis
• pH <7.38
• [𝑯𝑪𝑶𝟑 ] <22 mmol/liter
• Secondary (respiratory) response:
• PaCO2 = 1.5 × [𝑯𝑪𝑶𝟑 ] + 8±2 mm Hg
or
• PaCO2 = [𝑯𝑪𝑶𝟑 ] + 15 mm Hg
• Complete secondary adaptive
response within 12–24 hr
𝑷𝒂𝑪𝑶𝟐
𝑽𝑪𝑶𝟐
𝑽𝑨
𝒑𝑯 𝒑𝑲 𝒍𝒐𝒈𝟏𝟎
𝑯𝑪𝑶𝟑
𝜶𝑪𝑶𝟐
𝑷𝑪𝑶𝟐
𝑷𝒂𝑶𝟐 𝑭𝒊𝑶𝟐 𝟓
by: Reza Nejat, M. D., FCCM; Anti‐Doping, Nutrition,
Metabolism Consultant

28. ABG: an indicator of
physical endurance
post-cardiac surgery?
• Metabolic alkalosis
• pH >7.42 and
• [𝑯𝑪𝑶𝟑 ] >26 mmol/liter
• Secondary (respiratory) response:
• Paco2 = 0.7 × ([𝑯𝑪𝑶𝟑 ] − 24) + 40±2 mm
Hg
or
• Paco2 = [𝑯𝑪𝑶𝟑 ] + 15 mm Hg
or
• Paco2 = 0.7 × [𝑯𝑪𝑶𝟑 ] + 20 mm Hg
• Complete secondary adaptive
response within 24–36 hr
Metabolic acidosis
pH <7.38 and [𝑯𝑪𝑶𝟑 ] <22 mmol/liter
Secondary (respiratory) response:
PaCO2 = 1.5 × [𝑯𝑪𝑶𝟑 ] + 8±2 mm Hg
or
PaCO2 = [𝑯𝑪𝑶𝟑 ] + 15 mm Hg
Complete secondary adaptive response
within 12–24 hr
by: Reza Nejat, M. D., FCCM; Anti‐Doping, Nutrition,
Metabolism Consultant

29. ABG: an indicator of
physical endurance
post-cardiac surgery?
• Respiratory acidosis
• pH <7.38 and PaCO2 >42 mm Hg
• Secondary (metabolic) response
• Acute:
• [𝑯𝑪𝑶𝟑 ]= 24+(2mmol/liter/10mmHg
increase of PaCO2 above 40 mm Hg)
• ∆𝑯𝑪𝑶𝟑 𝟎. 𝟐∆𝑷𝒂𝑪𝑶𝟐
• Chronic:
• [𝑯𝑪𝑶𝟑 ]=24+ (5 mmol/liter/10mmHg
increase of PaCO2 above 40 mm Hg)
• ∆𝑯𝑪𝑶𝟑 𝟎. 𝟓∆𝑷𝒂𝑪𝑶𝟐
• Complete secondary adaptive
response within 2–5 days
𝑷𝒂𝑪𝑶𝟐
𝑽𝑪𝑶𝟐
𝑽𝑨
𝒑𝑯 𝒑𝑲 𝒍𝒐𝒈𝟏𝟎
𝑯𝑪𝑶𝟑
𝜶𝑪𝑶𝟐
𝑷𝑪𝑶𝟐
𝑷𝒂𝑶𝟐 𝑭𝒊𝑶𝟐 𝟓
by: Reza Nejat, M. D., FCCM; Anti‐Doping, Nutrition,
Metabolism Consultant

30. ABG: an indicator of
physical endurance
post-cardiac surgery?
• Respiratory alkalosis
• pH >7.42 and PaCO2 <38 mm Hg
• Secondary (metabolic) response
• Acute:
• [𝑯𝑪𝑶𝟑 ]= 24 (2 mmol/liter/10 mmHg
decrease of PaCO2 below 40 mm Hg)
• Chronic:
• [𝑯𝑪𝑶𝟑 ]= 24 (4–5 mmol/liter/10 mmHg
decrease of PaCO2 below 40 mm Hg)
• Complete secondary adaptive
response within 2–5 days
Respiratory acidosis
pH <7.38 and PaCO2 >42 mm Hg
Secondary (metabolic) response
Acute:
[𝑯𝑪𝑶𝟑 ]= 24+(1mmol/liter/10mmHg
increase of PaCO2 above 40 mm Hg)
Chronic:
generally [𝑯𝑪𝑶𝟑 ]=24+ (4–5
mmol/liter/10mmHg increase of PaCO2
above 40 mm Hg)
by: Reza Nejat, M. D., FCCM; Anti‐Doping, Nutrition,
Metabolism Consultant

31. ABG: an indicator of
physical endurance
post-cardiac surgery?
• 𝒑𝑯, 𝑷𝑪𝑶𝟐, 𝑯𝑪𝑶𝟑 𝒐𝒓 ?
 Adding 10 mmol/l acid what happens to 𝑯𝑪𝑶𝟑 24mmol/l
• 𝐓𝑪𝑶𝟐 𝒅𝒊𝒔𝒔𝒐𝒍𝒗𝒆𝒅 𝑪𝑶𝟐 𝑯𝑪𝑶𝟑 𝑹 𝑵𝑯𝟐 𝑪𝑶𝟐
• 𝒂𝑯𝑪𝑶𝟑 𝒂𝒏𝒅 𝒔𝑯𝑪𝑶𝟑 ;
• Buffer Buffer (BB)= 𝑯𝑪𝑶𝟑 𝑨 𝒑𝒓𝒐𝒕𝒆𝒊𝒏𝒔, 𝑯𝒃
• ∆𝑩𝑩 𝑩𝑩 𝑵𝑩𝑩 → 𝑩𝑬
• 𝑩𝑬𝒃 𝒐𝒓 𝑩𝑬𝒆𝒄𝒇
• BE = 0.9287 × [(bicarbonate −24.4) + β(pH -7.4)]
• 𝑷𝑪𝑶𝟐 𝟏𝟐𝒎𝒎𝑯𝒈 ↔ 𝒑𝑯 𝟎. 𝟏 ↔ 𝑩𝑬 𝟔𝒎𝒒/𝒍
Debt of 𝑶𝟐→ Base Excess (BE)
‐2↔+2 (meq/L) normal
‐3‒‐5 mild
‐6‒‐9 moderate
<‐10 severe
by: Reza Nejat, M. D., FCCM; Anti‐Doping, Nutrition,
Metabolism Consultant

32. ABG: an indicator of
physical endurance
post-cardiac surgery?
by: Reza Nejat, M. D., FCCM; Anti‐Doping, Nutrition,
Metabolism Consultant