Clinical need-directed blood tests: a step in saving the NHS?

Appropriate use of plasma glucose tests for diagnosis of diabetes mellitus in Ibadan, Nigeria

Background: Diabetes mellitus is a growing epidemic in Africa. Its diagnosis relies exclusively on laboratory evidence, which differs based on clinical circumstances.Objective: The study described the appropriateness of plasma glucose test requests per the American Diabetes Association criteria.Methods: We reviewed the plasma glucose test requests received by the chemical pathology laboratory of the University College Hospital, Ibadan, Nigeria between June 2018 and November 2018. The American Diabetes Association diabetes diagnostic criteria were used to define the appropriateness of test requests and determine the potential for ill-informed clinical decisions.Results: Four hundred and twenty-three requisition forms were included, with the majority from the medical wards/clinics (72.3%); the most frequent reason for a plasma glucose test was systemic hypertension (28.6%). Fasting plasma glucose was most requested (254; 60.0%). One hundred and sixteen (27.4%) requests were potentially inappropriate, with the 2-h postprandial plasma glucose (2hPPG) test requests (83; 71.6%) being the most inappropriate. The difference in the proportion of inappropriate requests was not statistically significantly between medical or surgical wards/clinics (Odds ratio 1.131, 95% confidence interval 0.709–1.803, p = 0.605). Inappropriate requests in six cases may have triggered inappropriate action.Conclusion: A third of the glucose tests requested for querying diabetes mellitus may have been inappropriate. Results of such testing may trigger inappropriate clinical action. To improve the quality of care and for economic reasons, laboratories should have programmes to improve the appropriate use of their services.

Psychiatrists should investigate their patients less

Psychiatrists often order investigations such as blood tests, neuroimaging and electroencephalograms for their patients. Rationales include ruling out 'organic' causes of psychiatric presentations, providing baseline parameters before starting psychotropic medications, and screening for general cardiometabolic health. Hospital protocols often recommend an extensive panel of blood tests on admission to a psychiatric ward. In this Against the Stream article, we argue that many of these investigations are at best useless and at worst harmful: the yield of positive findings that change clinical management is extremely low; special investigations are a poor substitute for a targeted history and examination; and incidental findings may cause anxiety and further unwarranted investigation. Cognitive and cultural reasons why over-investigation continues are discussed. We conclude by encouraging a more targeted approach guided by a thorough bedside clinical assessment.

Reducing the number of unnecessary laboratory tests within hospital through the use of educational interventions

BACKGROUND

The growing number of laboratory investigation requests is placing an increased burden upon NHS resources. Around a quarter of all tests are unnecessary repeats, and almost a third have no impact on patient management. Doctors recognise that tests should only be performed when clinically indicated, but a culture persists of undertaking unnecessary repeat investigations.

METHODS

A cohort study was undertaken at a district general hospital to observe the impact of introducing educational interventions in the form of a poster and a series of educational lectures, encouraging clinicians to consider whether an investigation was clinically indicated. Data was collected from nine different sites across the hospital run by different medical teams regarding the number of tests undertaken and the impact on patient care.

RESULTS

Data from over 13,000 tests and over 2000 patients was analysed from nine different sites across the hospital. There was a significant reduction (33%, p = 0.0001) in the number of blood tests performed. This reduction in testing saved £7006 over the course of 1 month, in addition to other benefits. There was a reduction in testing in eight out of the nine sites in which the study was undertaken, demonstrating good generalisability of results. There was no significant increase in length of admission or mortality.

CONCLUSION

Educational interventions to doctors have a significant and safe impact in reducing the number of unnecessary investigations, providing cost saving benefits to the NHS.

Targeted ordering of investigations reduces costs of treatment for surgical inpatients

BACKGROUND

Laboratory testing forms an important part of diagnostic investigation in modern medicine; however, the overuse of 'routine blood tests' can result in significant potential harm and financial cost to the patient and the healthcare system. In 2018, a new protocol targeting the ordering of investigations was implemented within the General Surgical Teams of Wollongong Hospital in New South Wales, an Australian tertiary referral hospital, to reduce the number of 'routine blood tests' as a quality improvement initiative.

OBJECTIVE

To identify whether there was a reduction in the number of 'routine blood tests' and associated costs following implementation of the new protocol.

METHODS

The protocol involved regular review of the laboratory investigations being ordered for the following day with a senior team member. The medical records of all patients admitted under the general surgery service at Wollongong Hospital were retrospectively reviewed over two 10-week periods in 2017 and 2018 (control and study, respectively). The casemix was categorized into Minor, Intermediate, Major or Unscored, depending on case complexity coding.

RESULTS

A total of 838 patients were identified during the control period (2017) and 805 patients were identified during the study period (2018). Ten thousand and thirty tests were included in the control period, compared to 8610 over the study period, resulting in a 16% (or greater) reduction in 'routine blood tests' per patient, per day of admission and a 6% reduction in costs in the study group (P < 0.001).

CONCLUSION

Targeted ordering of investigations with personalized education and feedback to junior staff during review of clinical status of each patient as a part of normal workflow can reduce inappropriate ordering of 'routine blood tests' and associated costs to the patient and the healthcare system.

Serum D-dimer should not be used in the diagnosis of venous thromboembolism within 28 days of total knee replacement surgery

Background

Serum D-dimer is frequently used to rule out a diagnosis of venous thromboembolism (VTE), a recognised complication following total knee replacement (TKR). TKR is known to cause a rise in D-dimer levels, reducing its specificity. Previous studies have demonstrated that D-dimer remains elevated within 10 days of TKR and therefore should be avoided. The aim of this study was to determine whether serum D-dimer tests are clinically appropriate in identifying VTE when performed within 28 days of TKR.

Methods

Case notes for patients who had a serum D-dimer test performed for clinically suspected VTE at ≥ 28 days following TKR were retrospectively reviewed for a 6-year period. Demographics, D-dimer result, time after surgery and further radiological investigations were recorded.

Results

Fifty patients underwent D-dimer tests at ≥ 28 days following surgery (median 60 days, range 29–266); 48 of these patients had a positive result. Of these, five had confirmed VTE on radiological investigations. Serum D-dimer was raised in 96% of the patients. Only 10.42% of these patients had confirmed VTE. No patients with negative D-dimers had confirmed VTE.

Conclusions

These findings suggest that serum D-dimer remains raised for at least 28 days and possibly considerably longer following TKR. Serum D-dimer should not be used in patients with clinically suspected VTE within this period because of its unacceptably low specificity of 4.44% and positive predictive value of 10.42%, which can lead to a delay in necessary further radiological investigations, waste of resources and unnecessary exposure to harm.

Decreasing daily blood work in hospitals: What works and what doesn't

Recurrent, inappropriate laboratory testing is a costly and wasteful use of healthcare resources. Recognizing this problem, the American Board of Internal Medicine, Canadian Society of Internal Medicine, and the Canadian Association of Pathologist all supported the Choosing Wisely campaign to reduce laboratory investigations in patients who demonstrate clinical and laboratory stability. In this narrative, we review studies looking at a variety of approaches to reduce excessive testing including education, audit and feedback, computerized physician order entry system changes, and forcing functions. Each type of intervention has its own unique advantages and disadvantages, varying in complexity, disruptiveness, effectiveness, and sustainability. Before implementing any quality improvement project, it is important to analyze the local context to identify the root causes for the practice behavior and aim to use the minimal amount of intervention to achieve the desired result. Change is often incremental and will seldom occur with a single intervention or Plan-Do-Study-Act cycle. Garnering the support of opinion leaders and a quality improvement team will help make the process and intervention a success.

Reducing the number of unnecessary liver function tests requested on the Paediatric Intensive Care Unit

Between January and October 2014, Great Ormond Street Hospital Paediatric Intensive Care Unit (PICU) was spending an average £23,392 on blood tests per month. Blood tests should be requested based on previous results and the patient's clinical condition, medication and nutritional status. However, more blood tests were being ordered than clinically indicated: an audit in October 2014 showed liver function tests (LFTs) were requested daily on most patients, even with previous normal results. A driver diagram identified three primary drivers for blood test requesting: decision-making, situational awareness and computer-based ordering. Decision-making for routine blood tests was the responsibility of the bedside nurses on each night shift. The communication between the nurses and doctors was an identified secondary driver. The project's primary aim was to reduce unnecessary LFTs requests on PICU over 6 months by implementing a blood test request form, a table of common investigations to facilitate and document discussion between the nursing and medical teams. The secondary aims were to reduce other unnecessary blood test requests, including full blood counts (FBC), coagulation screens and CRP. This project was conducted in three phases: construction, testing and implementation of the blood test form. PDSA cycles were used within each phase. Two PICU nurse champions were engaged to provide bedside support, education and feedback. In the 8-month period following implementation, there was a significant sustained reduction in LFTs requests. A similar pattern of sustained reduction also occurred for FBC, coagulation screens and CRP requests. This sustained reduction in blood tests requested equated to a saving in excess of £36,000. This project was successful: the reduction in the number of inappropriate blood tests had clear financial benefit for PICU and reduced blood loss for patients. Early engagement and support from key stakeholders avoided conflict, guaranteed data sharing and aided engagement of bedside nurses.