Background The reconciliation process detects medicines errors and is a key point for improving patient safety.

Purpose To analyse the incidence, type and severity of reconciliation errors at Cardiology Unit admission.

Materials and Methods Descriptive prospective observational study from October-November 2011 in patients admitted to the Cardiology Unit in a tertiary hospital. Demographic data studied: sex and age.

The patient’s usual chronic treatment, obtained by comprehensive interview of the patient and by reviewing the clinical history, was compared with the medicines prescribed on admission in order to identify: no discrepancies (ND), intentional discrepancies (ID) (Formulary substitutions/modifications in response to a patient’s clinical status) and apparently unexplained discrepancies requiring clarification with the physician (DRCs). After clarification, Reconciliation Errors (REs) (discrepancies resulting in physician order changes) were classified by type and severity.

Results 113 patients were included. The median age was 71.2 ± 10.4 years. 56.2% were male. Only 50 patients were reconciled due to logistical reasons.

528 medicines investigated: 159 ND (30.11%), 256 ID (48.49%) and 113 DRCs (21.40%).

After clarification, 47 (41.59%) DRCs were REs, while 5 discrepancies (4.42%) (2 patients) could not be resolved. 8.91% of prescriptions (47/528) were REs.

REs affected 22 (45.83%) of the 48 real study patients. The average number of REs per patient was 2.14 ± 1.21.

Types of RE were: omissions (n = 31), different dose/route/frequency (n = 7), unnecessary medicines (n = 5), wrong medicine (n = 3) and incomplete prescription (n = 1).

In terms of severity, REs were distributed as follows: No error, but possible (n = 10), error that does not reach the patient (n = 25), error reaching but not harmful (n = 11) and error requiring monitoring (n = 1).

Conclusions The process of taking a pharmacotherapeutic history at hospital admission is inadequate since almost half of the patients showed REs, mostly omissions.

Although most REs caused no harm, if perpetuated at discharge, they might have worse consequences and/or affect the effectiveness of treatment.

The pharmacist’s work in hospitalisation units is vital to reduce errors in care transitions and represents an opportunity to develop integral pharmaceutical attention in order to increase patient safety.

No conflict of interest.