Question

. Give me the pH CO2 and HCO-3 values for a old age patient that suffered an accidental overdose on heroin and is unresponsive, and explain

Answer 1

Heroin, also known as diacetylmorphine. Heroin is a strong agonist of opioid receptors.

In mild-to-moderate heroin overdoses, arterial blood gas (ABG) analysis reveals respiratory acidosis.

In more severe overdoses, tissue hypoxia is common, leading to mixed respiratory and metabolic acidosis

Respiratory acidosis

PH- less than 7.35 ( eg: 7.22)

Normal is 7.35-7.45

Pco2 more than 45 mm of Hg ( eg: 50 mm of Hg)

Pco2- 35-45 mm of Hg

Hco3- ion elevated - more than 26 mEq/L (eg:30)

Normal- 22-26 mEq/Litter

Heroin has effects on the opioid receptors, particularly the mu receptor causes respiratory depression results in an increased amount of carbon dioxide and decreased amount of oxygen in the bloodstream.

Production of carbon dioxide occurs rapidly and failure of ventilation promptly increases the partial pressure of arterial carbon dioxide (PaCO₂). Alveolar hypoventilation leads to an increased PaCO₂ (ie, hypercapnia) and elevated bicarbonate ions

The increase in PaCO₂, in turn, decreases the bicarbonate (HCO₃^–)/PaCO₂ ratio, thereby decreasing the pH.

In severe opioid toxicity mixed respiratory and metabolic acidosis occur . It is evidenced by a combination of a high pCO2 and a low bicarbonates.

Eg :

PH- 7.2

Pco2- 50 mm of Hg

HCo3-- 20 mEq/L