Acid and Base Balance and Imbalance-investigations and case discussion

Dr. WASIF ALI KHANMD-PATHOLOGY (UNIVERSITY OF BOMBAY)

Assistant Prof. in PathologyAl Maarefa College

Normal reference values

• pH—blood-7.35 to 7.45-avg-7.4• The normal reference range for PaCO2 is 35-45

mm Hg.• The normal reference range for PaO2 is 75-100

mm of Hg.• Normal bicarbonate level-HCO3 – 22–26 mEq/LO2 saturation— 95-100%

Blood gas analyser

Pulse Oximeter

Step-wise interpretation of ABG Report

• pH• pCO2

• HCO3

• O2 saturation.

Case-no-1

• A 40 year old female patient presented in the emergency department in a stuporous state. Her relative gave history of diabetes mellitus of 8 years duration. Clinically her skin was warm and breath had a sweet odor with deep and rapid respiration.

Blood reportBlood sugar- 350mg/dl. pH--- 7.10Pco2 --- 40 mm of Hg (normal—35-45 mm

of Hg).HCO3---25 mEq/l—(Normal-22-26 mEq/l).

O2 saturation—95%-( Normal is 95-100%)

Questions

• 1) What does the history of patient indicate?• 2) What is the cause of sweet odor?• 3) What is the cause of stuporous state?• 4) What is the cause of rapid breathing?• 5) Interpret laboratory data.• 6) What is your diagnosis?• 7) how will you treat this patient?

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Question no-2

• A patient is in intensive care because he suffered a severe myocardial infarction 3 days ago. The lab reports the following values from an arterial blood sample:– pH 7.3– HCO3- = 20 mEq / L ( 22 - 26)– pCO2 = 32 mm Hg (35 - 45)

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Diagnosis

• Metabolic acidosis• With compensation

Question 3

• A 70 year chronic smoker was admitted with complaints of restlessness, breathlessness and productive cough.

Blood report

pH--- 7.20Pco2 --- 65 mm of Hg (normal—35-45 mm

of Hg).HCO3---28 mEq/l—(Normal-22-26 mEq/l).

O2 saturation—85%-( Normal is 95-100%)

Diagnosis• Respiratory Acidosis with compensation.

ABG Report

– pH 7.3

– pCO2 = 32 mm Hg (35 - 45)

– HCO3- = 20 mEq / L ( 22 - 26) O2 saturation is normal.