Introduction: Why Stopping Bad Lab Habits Improves Patient Care

Hospitals across the world rely heavily on lab testing to diagnose and monitor disease — but sometimes, that dependence turns into habit rather than necessity. Bad lab habits in hospitals not only waste time and resources but also cause unnecessary discomfort for patients.

This guide highlights eight common lab practices that should be stopped immediately. You’ll learn why these tests don’t add clinical value when repeated unnecessarily — and what to do instead to provide evidence-based, patient-centered care.

1. Trending Ammonia for Hepatic Encephalopathy (HE)

Why Ammonia Isn’t a Reliable Marker for HE

Ammonia testing is useful to support a diagnosis of hepatic encephalopathy, but daily trending offers little to no benefit. Studies show that ammonia levels do not correlate reliably with disease severity or response to treatment.

The Right Approach: Monitor Mental Status, Not Numbers

Once the diagnosis is made, clinical improvement should guide management. The patient’s mental status remains the most accurate indicator of progress — not fluctuating lab results.

👉 Key takeaway: Stop chasing ammonia numbers. Follow your patient, not the lab.

2. Ordering Daily Lipase or Amylase in Pancreatitis

Understanding When Lipase and Amylase Are Actually Useful

Lipase and amylase are valuable diagnostic tools for acute pancreatitis, but their utility ends there. Daily trending of these enzymes does not provide insight into disease recovery.

Clinical Indicators That Truly Reflect Recovery

Instead, monitor abdominal pain, oral intake tolerance, and systemic stability. These are the true indicators of whether pancreatitis is resolving.

👉 Key takeaway: Order lipase once to diagnose, not every morning to monitor.

3. Serial BNP Testing in Heart Failure Patients

Why BNP Shouldn’t Be Trended Daily

BNP and NT-proBNP are excellent for diagnosing heart failure, but serial testing rarely affects clinical management once the diagnosis is made. Daily BNP orders only add costs without improving care.

What to Monitor Instead of BNP

Rely on physical exam findings, daily weights, and diuretic response. These parameters more accurately reflect fluid status and treatment efficacy.

👉 Key takeaway: Use your stethoscope and scale more than the lab slip.

4. AST and ALT in Hepatitis: Stop Obsessing Over Numbers

The Real Markers of Liver Function

Elevated AST and ALT levels indicate hepatocellular injury but don’t directly measure liver function. For functional assessment, INR and bilirubin are far more meaningful.

When to Safely Discharge Despite Elevated AST/ALT

Don’t delay discharge solely due to persistent enzyme elevation. Enzyme normalization can lag weeks behind clinical improvement. Focus instead on symptom resolution and synthetic recovery.

👉 Key takeaway: Elevated enzymes don’t equal instability.

5. Daily CBC, CMP, Magnesium, and Phosphate “Just Because”

Common Scenarios Where Routine Labs Are Unnecessary

Routine daily labs are often ordered for stable patients — even when the results won’t affect care. Unless there’s active bleeding, renal failure, severe infection, or critical electrolyte disturbance, repeat testing is unnecessary.

Clinical Judgment Over Habitual Testing

Use your clinical judgment. Order labs only when you expect the results to change management decisions.

👉 Key takeaway: Don’t let the computer order for you — think before you click.

6. Serial Troponins After PCI in Acute MI

What the Guidelines Actually Say About Post-PCI Troponins

According to major cardiology societies, serial troponin testing after successful PCI in confirmed MI patients adds no clinical value. Troponin levels may reflect infarct size but rarely influence management.

When a Follow-up Troponin Is Actually Warranted

Consider repeating only if reinfarction or stent thrombosis is suspected based on new symptoms or ECG changes.

👉 Key takeaway: Don’t trend troponins for curiosity’s sake.

7. Daily INR in Stable Warfarin Patients

Evidence-Based INR Monitoring Intervals

Stable warfarin patients don’t need daily INR checks. Guidelines recommend rechecking every few days during dose titration and every 4–12 weeks once stable.

Clinical Triggers for Additional INR Testing

Only order daily INR for bleeding events, drug interactions, or acute liver failure.

👉 Key takeaway: Check INR when it matters, not out of routine.

8. Daily CRP, ESR, or Procalcitonin Without Indication

Why Trending Inflammatory Markers Adds Little Value

Inflammatory markers like CRP, ESR, and procalcitonin often fluctuate slowly and lag behind clinical recovery. Daily monitoring rarely provides actionable insight.

Smarter Use of Inflammatory Biomarkers

Reserve these tests for specific infection monitoring or treatment discontinuation decisions, not for routine trending.

👉 Key takeaway: Use inflammatory markers wisely and selectively.

The Hidden Costs of Bad Lab Habits in Hospitals

Impact on Patients and Hospital Resources

Each unnecessary test means another needle stick, another anxiety-inducing result, and added costs to the system. Overordering also increases lab workload and burnout among healthcare staff.

How to Build a Culture of Smarter Lab Ordering

Hospitals should implement evidence-based testing protocols, provide education for residents, and encourage feedback loops to prevent wasteful ordering.

For more guidance, refer to Choosing Wisely, a campaign promoting evidence-based healthcare practices.

FAQs About Bad Lab Habits in Hospitals

1. Why are unnecessary lab tests a problem in hospitals?
They waste resources, can cause patient discomfort, and rarely alter management decisions.

2. What is a good rule of thumb before ordering a test?
Ask: “Will this result change my management?” If not, don’t order it.

3. How can hospitals reduce bad lab habits?
Through education, EMR alerts, and continuous quality improvement programs.

4. Which labs are most commonly overordered?
CBC, CMP, magnesium, phosphate, and CRP are the top offenders.

5. Should we ever trend ammonia or lipase daily?
No — neither provides reliable clinical information over time.

6. How can clinicians promote smarter testing?
By prioritizing clinical evaluation and using labs to confirm — not replace — their judgment.

Conclusion: Smarter Testing Means Better Medicine

Breaking bad lab habits in hospitals isn’t just about saving money — it’s about enhancing patient care and focusing on what truly matters. By replacing reflexive ordering with thoughtful testing, clinicians can reduce harm, improve outcomes, and restore the art of medicine.