In cases where it is possible to continue treatment at home, patients are often prescribed intravenous therapy at home. This is welcomed by the patients themselves and reduces the length of their stay at the clinic. However, there is evidence that during prolonged intravenous therapy at home, antibiotics are administered in higher concentrations and stored at a higher temperature than in the clinic. The concentrations are higher because the volume of the solvent is limited by the volume of the container containing the antibiotic. In addition, the storage temperature of the substance is obviously higher than in the clinic, since the container containing the antibiotic is attached to the patient's body. On this basis, it can be assumed that the literature describing the stability of drugs as a function of temperature conditions does not correspond to the storage parameters of antibiotics administered intravenously at home.

The aim of the study, conducted in New Zealand, was to obtain temperature profiles of antibiotic reservoirs under conditions of intravenous therapy at home. After that, it was necessary to compare the stability of the sodium salt of benzylpenicillin during storage under these conditions and at a temperature of 3 to 5 ° C (temperature maintained by the refrigerator).

The Tinytag computer thermometer recorded the temperature of the antibiotic reservoir in nine patients every minute for 24 hours. In six patients, the capacity was fixed around the waist throughout the day and the other three removed it at night. The results are presented in the table:

After the results obtained, the stability of benzylpenicillin was studied during storage of the antibiotic at room temperature (21-22 ° C), 26 ° and 36 ° C. All plastic containers (IntraVia, Baxter Healthcare Corporation) containing 16 million units (9600 mg) of benzylpenicillin sodium salt (CSL) dissolved in 120 ml of phys. (Baxter Healthcare Corporation) were prepared under sterile conditions. The containers were stored at room temperature in the laboratory, as well as at a constant temperature of 26 ° C and 36 ° C in the incubator. Analysis of the benzylpenicillin concentration was performed every two hours by high performance liquid chromatography.

To simulate intravenous therapy with benzylpenicillin at home, five healthy volunteers for 48 hours (the first 24 hours, the container was fixed at the waist and the next 24 hours, the container was in bed) carried a container with 16 million units of the benzylpenicillin sodium salt dissolved in 120 ml of physics. solution. Analysis of the benzylpenicillin concentration was performed every four hours by high performance liquid chromatography.

The same containers were kept in the refrigerator at 3 to 5 ° C for 10 days, after which the analysis of the concentration of benzylpenicillin was also carried out.

Consequently, it has been shown that storing the antibiotic at 36 ° C causes a decrease in concentration of more than 10% after 5 hours 18 minutes from the time when the solution was prepared. At 26 ° C, this time was 12 hours 54 minutes and at room temperature - 13 hours 20 minutes. After one day, the concentration of benzylpenicillin fell to 5%, 61% and 83% at 36 ° C, 26 ° C and at room temperature, respectively.

In the study of containers carried by volunteers, the average time during which the antibiotic concentration dropped by more than 10% was 9 hours 20 minutes (from 4 hours 40 minutes to 15 hours 22 minutes). On average, the drop in benzylpenicillin concentration after 24 hours of wearing the container at the waist was 27%, and if the container was near the bed for a day, this time was considerably longer - 54%. By way of comparison, it must be said that the concentration of benzylpenicillin in containers stored at a temperature of 3 to 5 ° C did not decrease by 10% until after 8 days.

As a result, the researchers concluded that the thermally dependent breakdown of benzylpenicillin, which occurs during prolonged intravenous antibiotic therapy at home, can lead to a decrease in the effectiveness of antibiotic therapy.