Are baseline prothrombin time/partial thromboplastin time values necessary before instituting anticoagulation?

Are We Overusing Coagulation Studies in the Emergency Department?

Methods

This retrospective observational study, conducted in the ED of King Saud University Medical City (KSUMC) in Riyadh, Saudi Arabia, during July and August of 2021(2 months) examined coagulation profile requests. Patients' demographic data (age and gender), medical and clinical history (presenting complaint, comorbidities, and diagnosis), the use of antiplatelets or anticoagulant agents and laboratory values for PT, APTT, and INR were collected. We calculated the total cost of unnecessary coagulation profile testing based on the independent assessment of two ED consultants.

Results

Of 1,754 patients included in the study, 811 (46.2%) were males and 943 (53.8%) were females, with a mean age of 42.1 ± 18.5 years. There were 29 (1.7%) patients with liver disease and 21 (1.2%) patients had thromboembolic disease. The majority of the patients' results were within normal levels of PT (n = 1,409, 80.3%), APTT (n = 1,262, 71.9%), and INR (n = 1,711, 97.4%). Evidence of active bleeding was detected in 29 patients (1.7%). Among patients with bleeding only one had an abnormal INR (3.01) and was on warfarin. Forty-six (2.6%) patients had elevated INR level. Cohen's kappa between the two consultants was recorded at 0.681 (substantial agreement) in their assessment of the appropriateness of coagulation tests requests and both consultants believed that 1,051 tests (59.9%) were not indicated and were unnecessary. The expected annual cost saving if the unnecessary tests were removed would be around SAR 1,897,200 (approximately US$ 503,232) which is about SAR 180000 (US$ 48000)/1000 patients.

Conclusion

This study showed that coagulation tests are overused in the ED. More than half of coagulation profile tests in our study population were deemed unnecessary and associated with significant cost. Targeted testing based on specific patient presentation and medical history can guide physicians in wisely choosing who needs coagulation studies.

Reducing low-value ED coags across 11 hospitals in a safety net setting

BACKGROUND

Prothrombin/international normalized ratio and activated partial thromboplastin time (PT/INR and aPTT) are frequently ordered in emergency departments (EDs), but rarely affect management. They offer limited utility outside of select indications. Several quality improvement initiatives have shown reduction in ED use of PT/INR and aPTT using multifaceted interventions in well-resourced settings. Successful reduction of these low-value tests has not yet been shown using a single intervention across a large hospital system in a safety net setting. This study aims to determine if an intervention of two BPAs is associated with a reduction in PT/INR and aPTT usage across a large safety net system.

METHODS

This initiative was set at a large safety net system in the United States with 11 acute care hospitals. Two Best Practice Advisories (BPAs) discouraging inappropriate PT/INR and aPTT use were implemented from March 16, 2022-August 30, 2022. Order rate per 100 ED patients during the pre-intervention period was compared to the post-intervention period on both the system and individual hospital level. Complete blood count (CBC) testing served as a control, and packed red blood cell transfusions served as a balancing measure. An interrupted time series regression analysis was performed to capture immediate and temporal changes in ordering for all tests in the pre and post-intervention periods.

RESULTS

PT/INR tests exhibited an absolute decline of 4.11 tests per 100 ED encounters (95% confidence interval -5.17 to -3.05; relative reduction of 18.9%). aPTT tests exhibited absolute decline of 4.03 tests per 100 ED encounters (95% CI -5.10 to -2.97; relative reduction of 19.8%). The control measure, CBC, did not significantly change (-0.43, 95% CI -2.83 to 1.96). Individual hospitals showed variable response, with absolute reductions from 2.02 to 9.6 tests per 100 ED encounters for PT/INR (relative reduction 12.1%-30.5%) and 2.07 to 10.04 for aPTT (relative reduction 12.1%-31.4%). Regression analysis showed that the intervention caused an immediate 25.7% decline in PT/INR and 24.7% decline in aPTT tests compared to the control measure. The slope differences (rate of order increase pre vs post intervention) did not significantly decline compared to the control.

CONCLUSIONS

This BPA intervention reduced PT/INR and aPTT use across 11 EDs in a large, urban, safety net system. Further study is needed in implementation to other non-safety net settings.

Emergency medicine misconceptions: Utility of routine coagulation panels in the emergency department setting

BACKGROUND

Coagulation panels are ordered for a variety of conditions in the emergency department (ED).

OBJECTIVE

This narrative review evaluates specific conditions for which a coagulation panel is commonly ordered but has limited utility in medical decision-making.

DISCUSSION

Coagulation panels consist of partial thromboplastin time (PTT) or activated partial thromboplastin time (aPTT), prothrombin time (PT), and international normalized ratio (INR). These tests evaluate the coagulation pathway which leads to formation of a fibrin clot. The coagulation panel can monitor warfarin and heparin therapy, evaluate for vitamin K deficiency, evaluate for malnutrition or severe systemic disease, and assess hemostatic function in the setting of bleeding. The utility of coagulation testing in chest pain evaluation, routine perioperative assessment, prior to initiation of anticoagulation, and as screening for admitted patients is low, with little to no change in patient management based on results of these panels. Coagulation testing should be considered in systemically ill patients, those with a prior history of bleeding or family history of bleeding, patients on anticoagulation, or patients with active hemorrhage and signs of bleeding. Thromboelastography and rotational thromboelastometry offer more reliable measures of coagulation function.

CONCLUSIONS

Little utility for coagulation assessment is present for the evaluation of chest pain, routine perioperative assessment, initiation of anticoagulation, and screening for admitted patients. However, coagulation panel assessment should be considered in patients with hemorrhage, patients on anticoagulation, and personal history or family history of bleeding.

Cost-effectiveness of routine coagulation testing in the evaluation of chest pain in the ED

INTRODUCTION

Approximately 5% of all US emergency department (ED) visits are for chest pain, and coagulation testing is frequently utilized as part of the ED evaluation.

OBJECTIVE

The objective was to assess the cost-effectiveness of routine coagulation testing of patients with chest pain in the ED.

METHODS

We conducted a retrospective chart review of patients evaluated for chest pain in a community ED between August 1, 2010, and October 31, 2010. Charts were reviewed to determine the number and results of coagulation studies ordered, the number of coagulation studies that were appropriately ordered, and the number of patients requiring a therapeutic intervention or change in clinical plan (withholding of antiplatelet/anticoagulant, delayed procedure, or treatment with fresh frozen plasma or vitamin K) based on an unexpected coagulopathy. We considered it appropriate to order coagulation studies on patients with cirrhosis, known/suspected coagulopathy, active bleeding, use of warfarin, or ST-elevation myocardial infarction.

RESULTS

Of the 740 patients included, 406 (55%) had coagulation studies ordered. Of those 406, 327 (81%) patients with coagulation studies ordered had no indications for testing. One of the 327 patients (0.31%; 95% confidence interval, 0.05%-1.7%) tested without indication had a clinically significant coagulopathy (internationalized normalization ratio >1.5, partial thromboplastin time >50 seconds), but none (0%; 95% confidence interval, 0%-1.2%) of the patients with coagulation testing performed without indication required a therapeutic intervention or change in clinical plan. The cost of coagulation testing in these 327 patients was $16780.

CONCLUSIONS

Coagulation testing on chest pain patients in the ED is not cost-effective and should not be routinely performed.

Effect of CBC results on ED management of women with lower abdominal pain

Recent studies have suggested that the results of complete blood counts (CBCs) are neither sensitive nor specific in diagnosing abdominal pain, but no study has attempted to determine whether CBC results actually influence the management of ED patients. This study attempted to determine whether CBC results in women with lower abdominal pain affect ED disposition or diagnosis. One hundred women between the ages of 15 and 45 with lower abdominal pain presenting to a community hospital ED with an annual census of 45,000 were enrolled in this prospective study. Before review of the CBC results but after review of all other studies, the ED physician recorded a presumptive diagnosis and indicated whether consultation and/or admission were warranted. After the results of the CBC were reviewed, these factors were reassessed. Patient management or ED diagnosis was affected in two cases (2%; 95% confidence interval 0% to 7%), one resulting in appropriate discharge and one resulting in unnecessary admission. It was concluded that in young women with abdominal pain CBC results rarely affect clinical decision-making.