Gastric contents sampling

c505218304b50c59c3659f6dda43bae7-links-0–>Gastric content is a potentially valuable specimen for analysis in postmortem and clinical cases. Unabsorbed drug or tablet fragments in the gastric contents may provide valuable information concerning ingested compounds and provide an excellent material for preliminary screening owing to the potentially large amounts of drug that may be present. The absence of a drug in the gastric contents does not necessarily preclude oral administration. Odours emanating from the gastric content can provide valuable clues about what may have been consumed, e.g. pesticides and cyanides. The entire contents of the stomach should be collected and weighed. Gastric contents are non-homogeneous and should be homogenised prior to sampling. Quantitative drug determinations should be interpreted within the context of the entire contents (total quantity, rather than concentration) and it is important to take into consideration the differing absorption rates of drugs based on their physicochemical properties as well as their formulations and coatings.

The presence of a drug in gastric contents, particularly at low concentration,does not necessarily indicate orala dministration. Drugs may be absorbed into the stomach via gastric juices that are in equilibrium with blood or as a result of intranasal drug use. Basic drugs are more susceptible to this because they have a tendency to become trapped in the gastric compartment owing to the low pH. If heavy metals are suspected, gastric contents should be collected, together with intestinal contents. In cases of suspected poisoning where the patient may have survived for a few days in hospital prior to death and where drugs may have been metabolised and eliminated from the body prior to death, any stomach content collected and retained by medical staff may provide valuable information concerning drugs or poisons consumed.

Traduit en Français par : BENSAKHRIA Ayoub (source: Clarke's Analysis of Drugs and Poisons 3rd Edition)