Automated drug preparation apparatus including drug vial handling, venting, cannula positioning functionality

A method of withdrawing a prescribed amount of drug from a drug vial in an automated manner comprising the steps of:

• identifying the type of drug vial being used;
• accessing a database to retrieve one or more stored vial characteristics that are associated with the identified drug vial;
• positioning a vented needle relative to the drug vial based on the stored vial characteristics such that in a first mode of operation, a vent port of the vented needle is open and the drug vial is vented to atmosphere and in a second mode of operation, the vent port is closed;
• and drawing the prescribed amount of drug from the drug vial, wherein the stored vial characteristics include a draw angle that is a measure of the vented needle relative to a planar ground surface reference at a time of drawing drug and further including the step of:
• positioning the vented needle at the stored draw angle for the identified drug vial.

A method of withdrawing a prescribed amount of drug from a drug vial in an automated manner comprising the steps of:

• identifying the type of drug vial being used;
• accessing a database to retrieve one or more stored vial characteristics that are associated with the identified drug vial;
• positioning a vented needle relative to the drug vial based on the stored vial characteristics such that in a first mode of operation, a vent port of the vented needle is open and the drug vial is vented to atmosphere and in a second mode of operation, the vent port is closed;
• and drawing the prescribed amount of drug from the drug vial, wherein the step of drawing the prescribed amount of drug comprises the steps of:
• first positioning the vented needle in the first mode of operation and drawing a first volume of drug;
• and subsequently positioning the vented needle in the second mode of operation where only an open tip of the vented needle clears the septum and the vent port is closed to draw a second volume of drug that is substantially less than the first volume and where a sum of the first and second volumes at least about equals the prescribed amount of drug.

A method of withdrawing a drawing a prescribed dosage of medication from a drug vial comprising the steps of:

• identifying the type of drug vial being used;
• accessing a database to retrieve stored vial identification information that is associated with the identified drug vial, the vial identification information includes dimensions of a septum of the drug vial;
• retrieving a thickness of the septum from the stored septum dimensions;
• calculating, based on the thickness of the septum, a first position of a vented needle in a first mode of operation where both an open tip of the vented needle and the vent port clear the septum and are located in an interior chamber of the vial;
• calculating, based on the thickness of the septum, a second position of the vented needle in the second mode of operation where only the open tip end clears the septum and is located in the interior chamber;
• first positioning the vented needle in the first mode of operation and drawing a first volume of the medication;
• and subsequently positioning the vented needle in the second mode of operation where only an open tip of the vented needle clears the septum and the vent port is closed and drawing a second volume of medication that is substantially less than the first volume and where a sum of the first and second volumes is equal to a total volume of the prescribed dosage of medication.