hCG -HUMAN CHORIONIC GONADOTROPIC HORMONE

hCG is the hormone being detected in most pregnancy tests. It is normally produced by the placenta during pregnancy and is also markedly elevated in pathologic conditions like seminoma, hydatidiform mole and teratoma, among others.

TOXICOLOGY

www.freeimages.co.uk

Divisions of Toxicology

1. Emergency - deals with overdosage of drugs
2. Drug Abuse Screening- deals with substances of abuse
3. Therapeutic Drug Monitoring - deals with drugs for therapeutic use
4. Forensic - deals with the medical -legal aspect
5. Industrial - deals with industrial products.

EMERGENCY TOXICOLOGY

SALICYLATE poisoning - is the most common cause of ET in children.
Salicylate/acetysalicylate - the active component of aspirin.

DRUG ABUSE SCREENING

Most common substances of abuse are cigarette and alcohol.

THERAPEUTIC DRUG MONITORING

The purpose of this is to establish the optimum concentration of the drug that could cure the patient.

FORENSIC

Prohibited drugs are usually involved in this.

INDUSTRIAL

pesticides and insecticides are the most common substances involved.

BLOOD GAS ANALYSIS OUTLINE

The determination of blood gas is considered a special test in the local setting.
pCO2, pH and HCO3 are usually assayed. The results help in the evaluation whether a patient has acidosis or alkalosis.

Conditions:

Values : pH - decreased , PCO2 normal, HCO3 - decreased
Condition - metabolic acidosis
Compensatory mechanism - hyperventilation , increase excretion of CO2
decreased retention of CO2

Values: pH increased, HCO3 - increased , PCO2-normal
Condition - metabolic alkalosis
Compensatory mechanism - hypoventilation, decreased excretion of CO2
increased retention of CO2

Values : pH- increased , PCO2 - decreased , HCO3 -normal
Condition - respiratory alkalosis
Compensatory mechanism : increased retention of HCO3
decreased excretion of H+

Values: pH-decreased , PCO2 -increased, HCO3 -normal
Condition: respiratory acidosis
Compensatory mechanism : increased retention of HCO3,
increased excretion of H+

Henderson=Hasselbalch Equation: (H & H)


pH = 6.1 + log (HCO3)/DCO2

HCO = TCO2-DCO2

DCO2 = PCO2 X 0.031


Where: pH =indicates the acidity or alkalinity of a solution (hydrogen ion concentration.
HCO3 - bicarbonate
DCO2 - dissolved carbon dioxide
TCO2 - total carbon dioxide

Sample Problems:

Based on the following lab results obtained,
1. What is the acid base status of the patient?
2. What further test would you recommend?
3. What may be the possible causes of the condition?
4. Show all computations.

laboratory data:

TCO2 = 20 mmol/L
PCO2 = 30 mmHg

For more on blood gas analysis, visit the site below:

labtests on line