Variation in diagnostic testing in ICUs: a comparison of teaching and nonteaching hospitals in a regional system

Interventions to improve appropriateness of laboratory testing in the intensive care unit: a narrative review

Healthcare expenses are increasing, as is the utilization of laboratory resources. Despite this, between 20% and 40% of requested tests are deemed inappropriate. Improper use of laboratory resources leads to unwanted consequences such as hospital-acquired anemia, infections, increased costs, staff workload and patient stress and discomfort. The most unfavorable consequences result from unnecessary follow-up tests and treatments (overuse) and missed or delayed diagnoses (underuse). In this context, several interventions have been carried out to improve the appropriateness of laboratory testing. To date, there have been few published assessments of interventions specific to the intensive care unit. We reviewed the literature for interventions implemented in the ICU to improve the appropriateness of laboratory testing. We searched literature from 2008 to 2023 in PubMed, Embase, Scopus, and Google Scholar databases between April and June 2023. Five intervention categories were identified: education and guidance (E&G), audit and feedback, gatekeeping, computerized physician order entry (including reshaping of ordering panels), and multifaceted interventions (MFI). We included a sixth category exploring the potential role of artificial intelligence and machine learning (AI/ML)-based assisting tools in such interventions. E&G-based interventions and MFI are the most frequently used approaches. MFI is the most effective type of intervention, and shows the strongest persistence of effect over time. AI/ML-based tools may offer valuable assistance to the improvement of appropriate laboratory testing in the near future. Patient safety outcomes are not impaired by interventions to reduce inappropriate testing. The literature focuses mainly on reducing overuse of laboratory tests, with only one intervention mentioning underuse. We highlight an overall poor quality of methodological design and reporting and argue for standardization of intervention methods. Collaboration between clinicians and laboratory staff is key to improve appropriate laboratory utilization. This article offers practical guidance for optimizing the effectiveness of an intervention protocol designed to limit inappropriate use of laboratory resources.

Routine Versus On-Demand Blood Sampling in Critically Ill Patients: A Systematic Review

OBJECTIVES

We aimed to provide an overview of the current evidence on routine versus on-demand blood sampling in critical care. We assessed the reported proportion of patients exposed to daily routine blood sampling, the tests performed, characteristics associated with more frequent blood sampling, and the reported benefits and harms of routine blood sampling compared with on-demand sampling.

DATA SOURCES

We systematically searched the Cochrane Library, the Excerpta Medica Database, and the Medical Literature Analysis and Retrieval System Online for studies assessing routine versus on-demand blood testing in critically ill patients from inception to September 2022.

STUDY SELECTION

Abstracts and full texts were assessed independently and in duplicate by two reviewers.

STUDY EXTRACTION

Data were extracted independently and in duplicate by two reviewers using predefined extraction forms.

DATA SYNTHESIS

Of 12,212 records screened, 298 full-text articles were assessed for eligibility. We included 70 studies; 50 nonrandomized interventional studies and 20 observational studies. Exposure to routine blood testing was 52-100% (very low certainty of evidence). Blood testing seemed to occur more frequently in medical intensive care settings with a median of 18 blood tests per patient day (interquartile range, 10-33) (very low certainty of evidence). Mixed biochemistry seemed to be the most frequently performed blood tests across all settings (five tests per patient day; interquartile range, 2-10) (very low certainty of evidence). Reductions in routine blood testing seemed to be associated with reduced transfusion rates and costs without apparent adverse patient outcomes (low certainty of evidence).

CONCLUSIONS

In this systematic review, routine blood testing in critically ill patients was common and varied considerably. A reduction in routine blood testing appeared to be associated with reduced transfusion rates and costs without adverse effects, but the evidence was very uncertain.

Reducing unnecessary diagnostic phlebotomy in intensive care: a prospective quality improvement intervention

BACKGROUND

Critically ill patients receive frequent routine and recurring blood tests, some of which are unnecessary.

AIM

To reduce unnecessary routine phlebotomy in a 30-bed tertiary medical-surgical intensive care unit (ICU) in Toronto, Ontario.

METHODS

This prospective quality improvement study included a 7-month preintervention baseline, 5-month intervention and 11-month postintervention period. Change strategies included education, ICU rounds checklists, electronic order set modifications, an electronic test add-on tool and audit and feedback. The primary outcome was mean volume of blood collected per patient-day. Secondary outcomes included the number blood tubes used and red cell transfusions. Balancing measures included the timing and types of blood tests, ICU length of stay and mortality. Outcomes were evaluated using process control charts and segmented regression.

RESULTS

Patient demographics did not differ between time periods; total number of patients: 2096, median age: 61 years, 60% male. Mean phlebotomy volume±SD decreased from 41.1±4.0 to 34.1±4.7 mL/patient-day. Special cause variation was met at 13 weeks. Segmental regression demonstrated an immediate postintervention decrease of 6.6 mL/patient-day (95% CI 1.8 to 11.4 p=0.009), which was sustained. Blood tube consumption decreased by 1.4 tubes/patient-day (95% CI 0.4 to 2.4, p=0.005) amounting to 13 276 tubes (95% CI 4602 to 22 127 tubes) saved over 11 months. Red blood cell transfusions decreased from 10.5±5.2 to 8.3±4.4 transfusions/100 patient-days (incident rate ratio 0.56, 95% CI 0.35 to 0.88, p=0.01). There was no impact on length of stay (2 days, IQR 1-5) and mortality (18.1%±2.0%).

CONCLUSION

Iterative improvement interventions targeting clinician test ordering behaviour can reduce ICU phlebotomy and may impact red cell transfusions. Frequent stakeholder consultation, incorporating stewardship into daily workflow, and audit and feedback are effective strategies.

A descriptive study of routine laboratory testing in intensive care unit in nearly 140,000 patient stays

To describe the relationship between the use of laboratory tests and changes in laboratory parameters in ICU patients is necessary to help optimize routine laboratory testing. A retrospective, descriptive study was conducted on the large eICU-Collaborative Research Database. The relationship between the use of routine laboratory tests (chemistry and blood counts) and changes in ten common laboratory parameters was studied. Factors associated with laboratory tests were identified in a multivariate regression analysis using generalized estimating equation Poisson models. The study included 138,734 patient stays, with an ICU mortality of 8.97%. For all parameters, the proportion of patients with at least one test decreased from day 0 to day 1 and then gradually increased until the end of the ICU stay. Paradoxically, the results of almost all tests moved toward normal values, and the daily variation in the results of almost all tests decreased over time. The presence of an arterial catheter or teaching hospitals were independently associated with an increase in the number of laboratory tests performed. The paradox of routine laboratory testing should be further explored by assessing the factors that drive the decision to perform routine laboratory testing in ICU and the impact of such testing on patient.

Potentially redundant repeat liver function test ordering practices in australian hospitals: A 5-year multicentre retrospective observational study

BACKGROUND

Repeat Liver Function Tests (LFTs) are often necessary for monitoring purposes, but retesting within a short time interval may suggest potentially redundant repeat test (PRRT) ordering practices. We aimed to determine the proportion of potentially redundant repeat LFT ordering and identify associated factors in hospitals.

METHODS

A 5-year (2014-2018) retrospective cohort study in six hospitals in New South Wales, Australia. A total of 131 885 patient admissions with repeat LFTs in the general ward (n = 102 852) and intensive care unit (ICU) (n = 29 033) met the inclusion criteria. Existing guidelines do not support retesting LFT for at least 48-72 hours. We used 24 hours as a conservative minimum retesting interval to examine PRRT ordering. We fit binary logistic regression to identify factors associated with PRRT ordering in two conditions with the highest repeat LFTs.

RESULTS

There were a total of 298 567 repeat LFTs (medians of 2 repeats/admission and retesting interval of 25.6 hours) in the general ward and 205 929 (medians of 4 repeats/admission and retesting interval of 24.1 hours) in the ICU. The proportions of PRRT ordering were 35.2% (105 227/298 567) and 47.7% (98 307/205 929) in the general ward and ICU, respectively. The proportions of patients who received at least one PRRT were 52.3% (53 766/102 852) and 83.9% (24 365/29 033) in the general ward and ICU, respectively. Age, gender and the number of comorbidities and procedures were associated with the likelihood of ordering PRRT depending on the settings.

CONCLUSION

Repeat LFT testing is common in Australian hospitals, often within 24 hours, despite guidelines not supporting too-early repeat testing. Further research should be conducted to understand whether better adherence to existing guidelines is required, or if there is any case for guidelines to be updated based on certain patient subpopulations.

Evaluating the long-term effects of a data-driven approach to reduce variation in emergency department pathology investigations: study protocol for evaluation of the NSW Health Pathology Atlas of variation

INTRODUCTION

Variation in test ordering is a major issue in Australia and globally with significant financial and clinical impacts. There is currently a lack of research identifying and remediating variation in the use of pathology tests in emergency departments (EDs). In 2019, NSW Health Pathology introduced the Pathology Atlas of Variation that uses a data-driven tool (the Atlas Analytical Model) to investigate test order variation across New South Wales (NSW) and engage with local health districts (LHDs) to reduce variation. The objectives of this study are to evaluate whether this data-driven approach is associated with: (1) a reduction in test order variation; (2) improvements in patient outcomes and (3) cost benefits, for the five most frequent ED presentations.

METHODS AND ANALYSIS

This is a large multisite study including 45 major public hospitals across 15 LHDs in NSW, Australia. The Atlas Analytical Model is a data analytics and visualisation tool capable of providing analytical insights into variation in pathology investigations across NSW EDs, which will be used as feedback to inform LHDs efforts to reduce variation. Interrupted time series analyses using 2 years pre Atlas (2017-2018) and 2 years post Atlas (2021-2022) data will be conducted. Study data will be obtained by linking hospital and laboratory databases. Funnel plots will be used to identify EDs with outlying pathology test ordering practices. The outcome measures include changes in test ordering practices, ED length of stay, hospital admission and cost benefits (total pathology costs per ED encounter).

ETHICS AND DISSEMINATION

The study has received ethical approval from the NSW Population and Health Service Research Ethics Committee (reference, 2019/ETH00184). The findings of the study will be published in peer-reviewed journals and disseminated via presentations at conferences. We will also engage directly with key stakeholders to disseminate the findings and to inform policies related to pathology testing in the ED.

Concurrent Proximal Fractures Are Rare in Distal Forearm Fractures: A National Cross-sectional Study

Introduction

Distal forearm fractures (DFF) account for 1.5% of emergency department (ED) visits in the United States. Clinicians frequently obtain imaging above/below the location of injury to rule out additional injuries. We sought to determine the incidence of associated proximal fractures (APF) in the setting of DFF and to evaluate the imaging practices in a nationally representative sample of EDs.

Methods

We queried the 2013 National Emergency Department Sample using International Classification of Diseases, 9th edition, diagnostic codes for DFF and APF. Current Procedural Technology codes identified associated imaging studies. We calculated national estimates using a weighted analysis of patient and hospital-level characteristics associated with APF and imaging practices. An analysis of costs estimated the financial impact of additional imaging in patients with DFF using Medicare reimbursement to approximate costs according to the 2018 Medicare Physician Fee Schedule.

Results

In 2013, an estimated 297,755 ED visits (weighted) were associated with a DFF, of which 1.6% (4836 cases) had an APF. The incidence of APF was lower among females (odds ratio [OR] (0.76); 95% confidence interval [CI], 0.64–0.91) but higher in metropolitan teaching hospitals compared to metropolitan non-teaching hospitals (OR [2.39]; 95% CI, 1.43–3.99) and Level 1 trauma centers (OR [3.9]; 95%, 1.91–7.96) compared to non-trauma centers. Approximately 40% (n = 117,948) of those with only DFF received non-wrist radiographs and 19% (n = 55,236) underwent non-wrist/non-forearm imaging. Factors independently associated with additional imaging included gender, payer, patient and hospital rurality, hospital region, teaching status, ownership, and trauma center level. Nearly $3.6 million (2018 U.S. dollars) was spent on the aforementioned additional imaging.

Conclusion

Despite the frequency of proximal imaging in patients with DFF, the incidence of APF was low. Further study to identify risk factors for APF based on mechanism and physical examination factors may result in reduced imaging and decreased avoidable healthcare spending.

Impact of the acute care nurse practitioner in reducing the number of unwarranted daily laboratory tests in the intensive care unit

BACKGROUND

Frequent laboratory testing may be necessary at times for critically ill patients. However, the practice of indiscriminate laboratory test ordering is common.

PURPOSE

The purpose of this quality improvement project was to assess the effectiveness of the acute care nurse practitioner (ACNP) in reducing the number of unwarranted laboratory tests ordered for ICU patients. To determine whether the presence of an ACNP would make a difference, an ACNP was present on daily ICU multidisciplinary rounds to facilitate the discussion of the laboratory testing needs for each patient for the following 24-hour period.

CONCLUSIONS

Eighty-one patients were enrolled in the project, 41 in the comparison and 40 in the intervention group. No significant differences were noted between the two groups. The project demonstrated that although there was an increase in tests ordered for the intervention group, the increase was brought about by an increase in specific individual tests rather than an increase in panels of laboratory tests. A reduction in patient cost was observed for the number of tests ordered. No increase in adverse events was noted.

IMPLICATIONS FOR PRACTICE

Acute care nurse practitioner presence on multidisciplinary rounds may be an effective method to change the practice toward the ordering of tests based on clinical indication.

Reducing Unnecessary Postoperative Complete Blood Count Testing in the Pediatric Intensive Care Unit

CONTEXT

Complete blood count (CBC) testing commonly occurs to determine the need for blood transfusions after surgical procedures. Many clinicians believe postoperative CBCs are "routine."

OBJECTIVE

To decrease unnecessary routine CBC testing in a low-risk cohort of postoperative patients in the pediatric intensive care unit (PICU) at The Children's Hospital of Philadelphia by 50% in 6 months.

DESIGN

Quality-improvement study. Data from our institution regarding frequency of ordering laboratory studies and transfusion requirements were collected for prior quality-improvement work demonstrating the safety and feasibility of avoiding routine postoperative CBCs in this cohort. Baseline survey data were gathered from key stakeholders on attitudes about and utilization of routine postoperative laboratory testing. Patient and clinician data were shared with all PICU clinicians. Simple Plan-Do-Study-Act cycles involving education, audit, and feedback were put into place.

MAIN OUTCOME MEASURES

Percentage of postoperative patients receiving CBCs within 48 hours of PICU admission. Balancing measures were hemoglobin level below 8 g/dL in patients for whom CBCs were sent and blood transfusions up to 7 days postoperatively for any patients in this cohort.

RESULTS

Sustained decreases below our 50% goal were seen after our interventions. There were no hemoglobin results below 8 g/dL or surgery-related blood transfusions in this cohort within 7 days of surgery. Estimated hospital charges related to routine postoperative CBCs decreased by 87% during 6 postintervention months.

CONCLUSION

A simple approach to a systemic problem in the PICU of unnecessary laboratory testing is feasible and effective. By using local historical data, we were able to identify a cohort of patients for whom routine postoperative CBC testing is unnecessary.

Do Consultants Follow Up on Tests They Recommend? Insights from an Academic Inpatient Gastrointestinal Consult Service

BACKGROUND

Inpatient care is a fundamental part of gastroenterology training and involves the recommendation, performance, and interpretation of diagnostic tests. However, test results are not always communicated to patients or treating providers. We determined the process of communication of test results and recommendations in our inpatient gastroenterology (GI) consult service.

METHODS

Test recommendations on 304 consecutive new GI consults (age 60.2 ± 1.0 year) over a 2-month period were recorded. Demographic factors (age, race, gender, zip code, insurance status) were extracted from the electronic medical record (EMR). Charts were independently reviewed 6 months later to determine results of recommended tests, follow-up of actionable test results, 30-day readmission rates, and predictors of suboptimal communication.

RESULTS

Of 490 recommended tests, 437 (89.2%) were performed, and 199 (45.5%) had actionable findings. Of these, 48 (24.1%) did not have documented follow-up. Failure of follow-up was higher for upper endoscopy (31.9%) compared to colonoscopy (18.0%, p = 0.07). Women (p = 0.07), patients on Medicare (p = 0.05), and procedures supervised by advanced GI fellows (p = 0.06) were less likely to receive follow-up. Median income and identification of a primary provider did not influence follow-up rates; 30-day readmission rates were not impacted. Female gender, insurance (Medicare) status, and attending type remained independent predictors of failure of follow-up on multivariate regression (p ≤ 0.03).

CONCLUSIONS

Failure to follow up test results on inpatient services at a large academic center was unacceptably high. Maximizing personnel participation together with diligence and technology (EMR) will be required to improve communication.

Predictors of intraoperative testing in adults undergoing noncardiac surgery within a regional hospital system

BACKGROUND

The use of intraoperative testing is central to anesthesia practice, and point-of-care testing (POCT) is often used. Nevertheless, POCT is costly and its contribution to patient outcome is unknown. There is a lack of guidelines to describe which patients should undergo intraoperative testing or how results should be applied. As such, we undertook a historical cohort study evaluating intraoperative testing practices within our region where POCT is not used.

METHODS

In 2012, we obtained a random sample of 1,000 adult patients undergoing noncardiac surgery in three of our health system hospitals. Patient, surgical, and testing details were extracted, and the surgical procedures were categorized using the Johns Hopkins risk guidelines. Our primary outcome was the administration of at least one intraoperative test. We used a multivariable logistic regression model to identify factors associated with testing and described the time from ordering the tests to receiving the results using descriptive statistics.

RESULTS

Study results showed that 110/1,000 (11.0%) patients underwent 413 diagnostic tests. Complete blood count was the most commonly administered test (36.3%), and the mean (standard deviation) time to obtain all test results was 29.9 (19.9) min. High-risk procedures were associated with an odds ratio (OR) of 12.3 (95% confidence interval [CI], 8.3 to 18.2; P < 0.001). Other predictors of intraoperative testing included emergency surgery (OR, 3.8; 95% CI, 2.0 to 7.2; P < 0.001), number of comorbidities (OR, 1.1; 95% CI, 1.0 to 1.2; P = 0.03), and duration of surgery (OR, 2.3; 95% CI, 1.8 to 2.9; P < 0.001).

CONCLUSION

Intraoperative testing is common and more likely in patients undergoing high-risk surgical procedures. In a central laboratory system, there is substantial time from ordering the tests to receiving the results. The clinical impact of this delay is unknown. Further evaluation is required regarding the relationship between the time required for intraoperative test results and perioperative outcomes.