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IMPLEMENTATION OF THE USE OF STANDARD MASSES CIRCUIT IN A PHARMACEUTICAL LABORATORY

European Statement

Patient Safety and Quality Assurance

Author(s)

Arce Sánchez, M; Álvaro Alonso, EA; Barrueco Fernández, N; Prieto Román, S; López Guerra, L; Sánchez Lorenzo, M; Flox Benítez, MP; Escobar Rodríguez, I.

Why was it done?

Accurate weighing of raw materials(RM) is a fundamental step in ensuring the quality and safety of compounding in a pharmaceutical laboratory(PL).

What was done?

Implement the use of standard masses(SM) to ensure that RM weighings performed in the PL analytical balance are as accurate as possible.

How was it done?

1.Balance employed is class I, with special accuracy, precision 1mg, and weighing range 10mg-220g. For this reason, E2 SM were purchased in accordance with the classification of the International-Organisation-Legal-Metrology(OIML). SM were calibrated by a laboratory accredited by the National-Accreditation-Entity(ENAC), stored under the same conditions as the balance, and handled according to manufacturer’s instructions.
2.A sensitivity test was performed to measure accuracy. The USP and chapter of the European-Pharmacopoeia, establish that the SM must be between 5% and 100% of the maximum weighing capacity of the balance. The test is satisfactory when the result obtained is within 0.1% of the nominal value(control-limit). An alert-limit was also establish(calculated as half control-limit).
3.A record form, standard-operating-procedure(SOP) and working circuit were designed. Before weighing RM, the pharmacy technician(PT) must verify leveling and internal calibration; weigh the selected SM, and record the result.
4.If weight is outside any limits, repeat internal calibration and weigh again. If it remains outside the alert-limit, the balance can be used, but the pharmacist must be notified to request external calibration. If it exceeds the control-limit, the balance cannot be used, and external calibration must be requested while another balance is employed.

What has been achieved?

SM acquired were: 10mg,20mg,20g,50g, and 100g. Those chosen to perform the sensitivity test were 20g and 100g(9.09% and 45.45% of maximum weighing balance capacity).
The range defined for 20g SM was 20g±20mg. Control-limit was 20g±10mg(19.990g-20.010g) and alert-limit was 20g±5mg(19.995g-20.005g).
The range defined for 100g SM was 100g±100mg. Control-limit was 100g±50mg(99.950g-100.050g) and alert-limit was 100g±25mg(99.975g-100.025g).
Since it was implemented in January-2025, all weighings have remained within the range.

What next?

The use of SM has shown to be a satisfactory circuit in ensuring the accuracy of the weighing of RM, used in the preparation of pharmaceutical compounding, thereby guaranteeing their safety and quality. This circuit could be established in other pharmacy departments.

Quality Improvement Project of Clozapine Prescribing Process in a Mental Health Unit

European Statement

Clinical Pharmacy Services

Author(s)

Charlotte Stafford, Aoife Delaney, Virginia Silvari, Thomas Cronin, Deirdre Lynch

Why was it done?

The Pharmacy Department dispenses clozapine to 142 patients. A new prescription was issued each time a patient was dispensed clozapine (approximately 40 new prescriptions per week). From January 2019 to June 2020 there were 42 clozapine incidents (incidents/month= 2) reported by the Pharmacy Department to the MHU. A four week review also showed that prescription queries (dose changes and transcription errors) consumed 6 hours of pharmacy staff time. The new 6-monthly, electronically stored prescription and the dedicated email address should address these issues.

What was done?

A newly devised proforma clozapine prescription has been developed by the Pharmacy Department and has become valid for 6 months for patients on 4-weekly blood monitoring. A copy of each patient’s prescription is stored electronically in the Mental Health Unit (MHU) share drive. A new dedicated pharmacy clozapine email address has been generated for all clozapine dose changes to be communicated to.

How was it done?

Four new clozapine prescriptions were developed by the Pharmacy Department:
– a maintenance dose prescription
– standard titration days 1 to 8
– standard titration days 8 to 15
– blank titration prescription.
The new prescriptions for patients on 4-weekly blood monitoring, valid for 6 months, are now stored in the MHU share drive to reduce the risk of transcribing errors.

What has been achieved?

Once the new system had been established, a further 4 week review showed that only 10 minutes over 4 weeks was spent by pharmacy staff dealing with a prescription query. All dose changes were now communicated by email. Incident reporting has decreased, with 5 clozapine incidents being reported by the Pharmacy Department between January to June 2021 (incident/month <1).

What next?

A business case highlighting the importance of a dedicated Clozapine Pharmacist has been submitted to further develop the clinic and ensure safety of this vulnerable cohort of patients.