Background Drug-drug interactions of current medications could increase the incidence of adverse effects.¹ Adverse drug interactions are the most frequent causes of drug iatrogenicity. Their incidence is proportional to drugs number and increases with a period extension of the prescription.

Purpose To determine nature and number of potential adverse drug interactions in a surgical intensive care unit (SICU).

Material and methods The pharmaceutical analysis was carried out over a 6 month period from September 2016 to March 2017 and involved patients hospitalised in a SICU.

Using a written document, we gather patients’ personal information and drug treatments:

• Number of patients.

• The epidemiological parameters (age, sex).

• Average length of stay.

• Number of drug interactions.

• Drug class according to the anatomical chemical therapeutic classification (ATC).

The levels of identified drug interactions are based on ‘Guideline on the Investigation of Drug Interactions’ edited by the French National Agency for the Safety of Medicines and Health Products (ANSM): warnings, precautions, possible adverse, contraindications.

Prescriptions are analysed using: THERIAQUE^®, Thesaurus ANSM 2016.

Averages and percentages were calculated using Microsoft Excel 2007.

Results Drug treatment of 131 patients was analysed. Forty-seven per cent were females and 53% were males, with mean age of 50.21±17.21 years.

Average length of stay: 8.18±14.79 days

The 131 lines of prescriptions analysed averaged 11.31±3 drugs (range: 3–20)

A total of 81 drug interactions was detected, 28% (n=23) pharmacokinetic and 72% (n=58) pharmacodynamic.

The drug classes:

• Antiinfectives for systemic use 23.53%.

• Nervous system 22.55% – cardiovascular system 15.69%.

• Alimentary tract and metabolism 15.69%.

• Blood and blood–forming organs 14.7%.

• Musculo–skeletal system 3.92% – respiratory system 2.94%.

• Systemic hormonal preparations, excluding sex hormones and insulins 0.98%.

The levels observed were eight warnings, 34 precautions, 35 possible adverse interactions and four contraindications.

The actual interactions observed were related especially to thrombocytopaenia.

Conclusion It seems important to maintain the vigilance of healthcare professionals in drug interactions and to integrate this risk into the assessment of the benefit/risk balance of drug treatments.

Reference and/or Acknowledgements 1. Bellmann, R. Personalised pharmacotherapy in intensive care unit patients. Med. Klin. Intensivmed. Notfallmedizin2017.

No conflict of interest