Blood samples are collected from patients, using strict aseptic technique and sterile equipment. The samples are inoculated into the blood culture bottles and mixed with the medium.
The formulation of the medium encourages the growth of aerobic, anaerobic and micro-aerophilic organisms. The medium is also designed to create pressure in the sealed bottle when organisms are growing. The detection of positive pressure is by means of a growth indicator device which is connected to the bottle after the blood sample is added.
A positive pressure in the bottle displaces a quantity of blood/broth mixture into the chamber as a sign of microbial activity.
A positive result is indicated when the blood/broth mixture rises above the green locking sleeve of the growth indicator device.
