Everything You Should Know About Lab Work

Everything You Should Know About Lab Work

By Daniel Haimowitz, MD, FACP, CMD, FPALTC

Ordering lab work is an integral part of taking care of patients. There may be opportunities in the long-term care continuum for making more informed choices and ordering fewer blood draws for laboratory tests in residents while avoiding potentially unnecessary expense for  facilities. The Choosing Wisely campaign identified lab tests as about 25% of all low-value services. This can be a complicated issue, so let’s dive into the specifics to present a framework that can help all involved.

The Evidence for Labs in the Nursing Home

There is little literature laying out the evidence for laboratory monitoring frequency in either the long-term care (LTC) setting or the short-term part A post-acute (PA) setting. Two studies examined the yield of routine lab ordering in skilled nursing facilities. The first found that only 16.7% of annual lab panels yielded at least one abnormality, suggesting that all beneficial abnormalities could be identified in basic tests such as complete blood count (CBC), electrolytes, renal function tests, thyroid function tests, and urinalysis. There was little evidence of benefit in routinely ordering comprehensive profiles.¹ The other was a study of severely impaired nursing home veterans showing that only 0.2% of individual tests resulted in patient benefit.  These data support the notion that comprehensive panels are not warranted in severely impaired LTC residents.² There are no good peer-reviewed studies or guidelines differentiating lab ordering frequency between part A PALTC settings. There is, however, some reasonably good literature providing suggested guidelines for labs specific to certain medications and associated conditions.  

Seek More Information

The first step for system and process improvement is to speak to the facility’s lab provider. Does the facility have access to laboratory utilization data? Is there an excessive volume (more than expected for the target population) of relatively low-cost tests (such as Vitamin D concentrations) or a low volume of high-cost tests (such as pharmacogenomic profiles)? Which prescribers are ordering which tests and how many of them? In residents with concerns of active bleeding, it is reasonable to obtain CBCs, but it is unlikely that all residents warrant monthly CBC testing. With this information, the facility can identify prescribing outliers and develop an action plan.  

In addition, ask the laboratory provider whether there are cost differences for specific tests. For example, is a CBC with differential more expensive than a CBC, and is that more expensive than just a hemoglobin level?  Sharing that information with ordering clinicians can impact behavior.  Additionally, sharing that information with nursing staff can also be important, since they may be unaware of the cost difference between two adjacent check boxes on a laboratory order slip.  

What is the expense of a complete metabolic profile versus a basic metabolic profile versus individual electrolytes (sodium, potassium, BUN, creatinine)? The primary decision point is whether the test is clinically appropriate. If not, avoid ordering it. If it is appropriate, is there a  less-costly test that can yield the needed clinical information?

Essential to this endeavor is to generate health-care provider-specific data. Physicians and physician associates will recognize that simply being presented with costs associated with lab testing in a vacuum is meaningless. Multiple issues need to be taken into consideration. For example:

• Costs need to be broken down between skilled/post-acute patients and LTC residents (and, if desired, between assisted living, memory care, and independent living residents). Another category to break out is hospice residents, where doing routine lab work is unlikely to change clinical management decisions or the resident’s quality of life.
• Time frame for follow-up lab work needs to be established. One week may be an insufficient time period in which to expect change, and a year probably is too long. A period of one to three months may be an optimum ordering frequency, depending on the acuity of the clinical issue, the number of lab tests generated, and the size of the facility.  Seasonal variations may also need to be considered as acute respiratory illness in the winter may appropriately prompt increased lab testing or imaging.
• Demographic characteristics such as age, race, sex, and underlying comorbidities may be relevant and affect ordering frequency.
• Establish a lookback period and separate out payer types,  such as Private Pay, Medicare Part A, Managed Medicare, and Medicaid for investigation.  
• Improving lab monitoring (a.k.a. “diagnostic stewardship”) can have many benefits, including reduced unnecessary repeat blood draws, decreased misdiagnosis of incidental electrolyte disorders, and less iatrogenic anemia.³

The goal is to make the collected data understandable, meaningful to providers, and actionable by the facility and providers. Confounding factors need to be taken into consideration—the data need to identify specific providers versus groups as a whole.  For example, on-call providers could be creating an issue in laboratory testing.

Post-Acute Patient Laboratory Issues

Patients in the facility for short-term rehabilitation fall into a separate category. They may arrive with orders from the hospital, they usually have a higher level of medical intensity than most custodial residents, and typically are seen at least weekly if not more often due to medical complexity. An overriding concern here is that for Medicare Part A residents, the facility is responsible for paying all laboratory costs. There is an opportunity to bring together ordering clinicians whose primary focus is clinical quality with the facility leaders who are charged with the economic viability of the institution. Medical care can be enhanced with sound clinical judgment and fiscal responsibility.

Points to Ponder

• Opinions vary as to whether to draw labs upon admission to the post-acute facility. Best practice is to individualize lab ordering and consider what lab work is available from other sources, especially the transferring hospital, before ordering only medically indicated laboratory tests. Some prescribers order labs on admission, others on the next lab day, others in a week, depending on the availability of recent laboratory results and the likelihood of a rapid change in clinical status. It's always better to try to obtain copies of recent tests than to reflexively repeat them.  Some clinicians order labs upon arrival to post-acute care “because our labs are always different than the hospital’s.” This perception may provide an opportunity to compare results obtained in the two different facilities. If a difference is found between the two facilities and it is consistent both in test and in direction, that may serve as an opportunity to partner with both the hospital and nursing home lab providers to determine the cause (different testing protocols, different calibration).
• Evaluate the need for lab orders sent with the resident to the facility upon hospital discharge to determine if they are indicated clinically. Recognize that many providers in acute care are inexperienced in the PALTC setting and may be unaware of practice differences and provision of age-friendly care focused on what matters to the resident. Sometimes practitioners are not informed about hospital-ordered labs when the medication reconciliation or verification of orders is performed. On occasion, recurring laboratory tests are ordered by hospital specialists that may not be needed following hospital discharge. Communication with the discharging physician at the hospital can clarify discrepancies between what is ordered and what is needed in some instances. The attending physician for a nursing home resident should be capable of making decisions about what lab work is necessary without requiring input from other clinicians (who may not have expertise in geriatric care).
• Scheduling standing lab tests as a monitoring mechanism. While there are published standards of monitoring as a benchmark (PharMerica)⁴, it can be confusing and lead to  unnecessary laboratory testing. One could consider developing a table of recommended labs for screening and medication monitoring, as noted above, with recommended frequencies to help standardize laboratory monitoring practices in the facility.
• Ordering labs for preventive health/routine health maintenance is not indicated for short-term patients. Tests such as lipid panels, Vitamin D concentrations, and HgbA1C tests can usually be deferred until after the patient is discharged from the skilled setting.  Note that outpatient circumstances are important here, and the facility should attempt to ensure that these sorts of tests are ordered upon discharge in the event the patient lacks a primary care provider in the community.
• Routine laboratory testing for older adults with hypertension increases costs and should only be considered when establishing a diagnosis or prognosis or if it will affect management decisions (e.g., with certain medications, such as diuretics, ACE Inhibitors, etc.).⁵
• Genetic or immunologic testing for which the facility will be financially responsible should be avoided unless medically necessary in the post-acute care setting and of some urgency. (Pharmacogenomic testing is a complicated issue. The theoretical rationale for nursing home residents is strong, but the evidence for hard clinical outcomes remains limited. The bottom line is that while the prevalence of actionable drug-gene interactions is high in this population, and theoretical and economic arguments are compelling, there has been no large, definitive randomized controlled trial demonstrating improved clinical outcomes specifically in nursing home residents. The high medication burden in this population makes it a reasonable consideration for selected residents receiving specific medications affected by genomic variants, but it is not a standard of care.⁶
• Some tests are not indicated at all. For example, levetiracetam (Keppra) is not dosed based on serum concentrations (the test is only indicated to monitor adherence, which should not be needed in the post-acute care setting.⁷ BNP testing is not a universal screening tool, is influenced by non-cardiac factors, and requires other confirmatory testing.⁸ Evidence does not support the use of pre-calcitonin levels to diagnose sepsis.⁹ Pre-albumin levels are short-phase reactants and should be ordered usually in seriously ill hospitalized patients, not to evaluate long-term nutrition status.¹⁰
• If you don’t know what a test is or have to look up what it’s used for, then it probably should not be ordered.
• Inappropriate ordering of urinalyses, urine cultures, and wound cultures is a discussion to be had in an antibiotic stewardship framework.

Test Ordering in Long-Term Residents

Some of the above concerns also apply to the long-term care resident population. Perhaps the most appropriate issue to tackle is whether the resident needs any blood work at all; in other words, does ordering lab work correlate with their goals of care? Do very elderly, hospice-appropriate residents really need lipid panels or HgbA1Cs? One could argue that even CBCs or BMPs may not be needed if residents, families, or attending physicians would be unlikely to act on potentially abnormal results.

A clinician might reasonably ask whether “routine labs” are likely to improve a resident’s quality of life, comfort, or level of function. Recognize that some nursing home residents who are enrolled in Medicare Advantage or other value-based models may have laboratory tests tied to quality incentives for the facility, the practice, or the health plan. In general, there are exceptions for those enrolled in hospice programs, those who carry a palliative care diagnosis (Z51.5), and other reasons. In addition, most value-based models that demand certain lab tests do not require 100% adherence to achieve the highest scores.

Most of these general principles apply in other health-care settings—assisted living (particularly in memory care), independent living, and even in the practitioner’s office.

Guidelines for Implementation for Change

So, where to start? Here are some proposed action steps.

1. Collect data that is as provider-specific as possible.
2. Track laboratory costs.
3. Collect data from the lab (if available)—which labs are ordered, by whom, and how often.  What are the indications for the labs, percentage of the labs that had abnormal results, etc. Are there tests included in the per diem, and if so, which ones? Also ask if there’s a list of contract pricing for the facility (see #7 below).
4. Identify opportunities where laboratory testing can be adjusted as above.
5. See if the facility is being charged more for stat labs compared to routine labs (and how much the charge is), and track whether stat labs are being ordered appropriately.
6. Determine if labs suggested or ordered by others (specialists, consultants, dietary, nursing staff, or DON) are appropriate.
7. See if your lab has cost differences between lab sets (i.e., panels) and individual laboratory tests.
8. Identify the most expensive lab sets and consider developing a semi-formal “pre-approval” process.
9. Be aware of how labs and studies are performed once they are ordered.  "Stat" carries different expectations for collection and reporting times in nursing homes versus assisted living and acute care centers.  Serum ammonia concentrations, rarely indicated, require prompt delivery to the laboratory, which practitioners and staff should be aware of when scheduling lab draws. Sometimes lab draw errors make blood that is drawn unable to be tested by the lab (a problem the facility may not be able to influence).
10. Educate your ordering practitioners (the "pre-analytic" part of lab ordering, compared to the gathering of retrospective data about prescribing practices within the facility, the "post-analytic" part).  Many of the points mentioned here are worthwhile. It could also be useful to educate them about the specific cost of tests, as they may not be informed of this.
11. Establish this process as a formalized performance improvement plan in quality assessment and performance improvement (QAPI), using data and discussion to inform and prioritize initiatives.

One could call this “patient-centered” laboratory testing, which would be effective and efficient, and is but one opportunity to consider in long-term care. Hopefully, some of these suggestions will be “news you can use” to develop a win-win for residents, the facility, and their organizations.  Spearheading this type of initiative validates medical directors as an important part of the leadership team.

(I would like to acknowledge the input of my colleagues Drs. Laurent Adler, Sing Palat, Karl Steinberg, and Bob Zorowitz, as well as the members of the PALTmed Community Forum.)

References:

(1)    Levinstein MR, Ouslander JG, Rubenstein LZ, Forsythe SB. Yield of routine annual laboratory tests in a skilled nursing home population. JAMA. 1987 Oct 9;258(14):1909-15. PMID: 3656601
(2)    Kim DE, Berlowitz DR. The limited value of routine laboratory assessments in severely impaired nursing home residents. JAMA. 1994 Nov 9;272(18):1447-52. PMID: 7933428
(3)    Diagnostic Stewardship to Prevent Diagnostic Error Morgan et al https://jamanetwork.com/journals/jama/article-abstract/2802248 2023
(4)    PharMerica Lab Monitoring Guide. https://pharmerica.com/wp-content/uploads/2020/12/Medication-Lab-Monitoring-Guide_2020-2021_FINAL.pdf
(5)    ACCF/AHA 2011 Expert Consensus Document on Hypertension in the Elderly https://www.ahajournals.org/doi/pdf/10.1161/cir.0b013e31821daaf6
(6)    El Rouby N, Johnson JA. Pharmacogenetic Testing - Evidence, Challenges, and Pathways to Adoption. NEJM Evid. 2025 Oct;4(10):EVIDra2400343. doi: 10.1056/EVIDra2400343. Epub 2025 Sep 23. PMID: 40985782.
(7)    https://www.droracle.ai/articles/462868/what-laboratory-tests-are-recommended-for-patients-on-keppra
(8)    Cigna Healthcare Plasma Brain Natriuretic Peptide in the Outpatient Setting https://v.static.cigna.com/assets/chcp/pdf/coveragePolicies/medical/mm_0028_coveragepositioncriteria_plasma_brain_natriuetic_peptide.pdf
(9)    Procalcitonin as a diagnostic marker for sepsis: a systematic review and meta-analysis. The Lancet: Infectious Diseases, 2013 
(10) MedLine Plus https://medlineplus.gov/lab-tests/prealbumin-blood-test/

Daniel Haimowitz is an internist and geriatrician in the Philadelphia suburbs. He is a multi-facility medical director, has been awarded both the PALTmed William Dodd and James Pattee awards, and is a long-time member of the Caring for the Ages Editorial Board.