ICU DRUG LEVEL MONITORING QI PROJECT

Dr Jack Sherlock, Dr Susi Paketci, Dr Anand Shankar

The Hillingdon Hospitals NHS Foundation Trust

Drug level monitoring is the sampling of patient blood at specific times in order to measure certain drug levels to ensure drug dosing is therapeutic and not toxic The use of drugs requiring monitoring is increased in the intensive care setting, owing to the higher acuity of patient and the drugs required to treat them. The most common group of drugs which require monitoring is antimicrobials, which are used at ten times the rate of other wards (Dulhunty et al, 2011).

Problem

Inaccurate drug level monitoring was identified by the Intensive Care Unit (ICU) Multidisciplinary Team (MDT) at Hillingdon Hospital as being a patient safety issue, alongside having many other negative consequences (see figure, right) The main issue was the timing of drug level samples, requested by the medics and performed by the nursing staff

To improve the proportion of drug levels that are taken at the correct time in Hillingdon Hospital ICU.

Methodology

Incorrectly timed drug levels Incorrectly adjusted doses Negative consequences

- Toxic drug levels

- Increased drug interactions

- Increased adverse effects

- Treatment failure through subtherapeutic dosing

- Wasted time

- Wasted resources

- Environmental cost

- Drug-specific issues i.e. antimicrobial resistance due to subtherapeutic levels

A list of the most commonly monitored ICU drugs was established within the ICU MDT Two plan-do-study-act (PDSA) cycles were then undertaken between January 2022 and July 2022 – the first establishing a baseline proportion of drug levels which were taken at the correct time; and the second delivering an intervention aimed at improving this proportion

Interventions

- Educational poster for ICU staff, distributed to each bed space Poster detailed timing of drug level, target levels, and when to give the drug after the level This was created in collaboration with the nursing staff, ICU lead pharmacist, and ICU lead consultant.

- Email distributed to nursing staff to inform them of the scale of the problem and explain the plan

- Discussion with nursing staff and junior medical staff to increase awareness of the educational poster.

Results

Within PDSA cycle 1, between 31st Jan 2022 -10th Feb 2022, 20 drug levels were taken from 7 different patients. 2/20 (10%) were taken within the pre-established correct times.

Following the interventions in PDSA cycle 2, between 26th May 2022 – 4th July 2022, 26 drug levels were taken from 10 different patients. 21/26 (80.8%) were taken within the correct time period.

Discussion

A clear improvement was demonstrated in the sampling of drug levels within the correct times following the introduction of the educational poster and promotion of the poster via email and discussion within the ICU MDT. This likely will have reduced risk to patients of having their drug dose altered incorrectly, exposing them to subtherapeutic or toxic drug levels. It would have also reduced the number of wasted drug level samples thus saving money, time, and reducing waste.

Limitations of the study included lack of assessment of whether patients’ drug doses were altered secondary to incorrectly timed samples and furthermore, whether the patient’s next drug level was outside of the therapeutic range. The sample sizes of the data were relatively small and the data collection periods also differed in length – the initial data collection period was cut short in view of the obvious need for improvement.

Further Developments

- Re-assessment of improvement at 12 months to see if the improvement has been sustained. The development of regular formal teaching for ICU staff regarding drug level monitoring could potentially help sustain the improvement.

- Nursing staff frequently mentioned that they were unsure whether they had to wait to give drug following drug level sampling. This could be assessed as drug administration delays would also impact on therapeutic levels.