Was the milrinone lactate (milrinone) and Zerbaxa (ceftolozane/tazobactam) home infusion therapy medically necessary for a patient with chronic systolic (congestive) heart failure (I50.22)?

Medical Necessity of Home Milrinone and Zerbaxa Therapy for Chronic Systolic Heart Failure

Direct Answer

Yes, both milrinone lactate and Zerbaxa (ceftolozane/tazobactam) home infusion therapy were medically necessary for this patient with chronic systolic heart failure (I50.22) given the documented clinical context of recurrent bacteremia requiring antibiotic therapy and advanced heart failure requiring palliative inotropic support.

Milrinone Lactate Home Infusion (J2260, S9348)

Medical Necessity Established

Milrinone is indicated as palliative therapy for end-stage heart failure patients who remain symptomatic despite optimal medical management, particularly when used as destination therapy or bridge to transplant. 1

The clinical documentation supports medical necessity through:

• Progressive left ventricular dysfunction: LVEF declined from 50-54% to 39%, then further deteriorated to 27%, demonstrating worsening systolic function despite initial improvement [@case documentation@]
• Previous response to milrinone: Patient had prior improvement on IV milrinone, which was discontinued when LVEF normalized, but required reinitiation when heart failure progressed [@case documentation@]
• Advanced heart failure status: Patient has nonischemic cardiomyopathy complicated by cardiogenic shock requiring home milrinone at 0.375 mcg/kg/min [@case documentation@]
• Palliative indication: Documented as "palliative milrinone" for advanced heart failure management [@case documentation@]

Guideline Support for Inotropic Therapy

While guidelines express caution about long-term inotropic therapy, they acknowledge specific clinical scenarios where it is appropriate:

• Inotropic agents are used to limit severe episodes of heart failure or as a bridge to heart transplantation in end-stage heart failure 2
• Home infusion milrinone reduces hospitalizations and overall treatment costs in advanced heart failure 3
• Continuous milrinone can serve as destination therapy for cardiac transplant or palliative therapy for cardiomyopathy 4

Important Caveats About Milrinone Use

The FDA warns that long-term milrinone therapy (>48 hours) has not been shown to be safe or effective and was associated with increased risk of hospitalization, death, and ventricular arrhythmias in a multicenter trial of 1088 patients with Class III-IV heart failure. 1 However, this applies to the general heart failure population, not specifically to:

• Patients awaiting transplant (bridge therapy)
• Patients with destination therapy needs
• Palliative care situations where quality of life is prioritized over mortality risk

The clinical context indicates this patient falls into the palliative/destination therapy category, where the risk-benefit calculation differs from standard heart failure management. 1, 4

Monitoring Requirements

When milrinone is used, the following must be documented:

• Continuous electrocardiographic monitoring capability to detect ventricular arrhythmias 1
• Blood pressure and heart rate monitoring with ability to adjust infusion rate 1
• Fluid and electrolyte monitoring, particularly potassium levels 1
• Renal function monitoring as milrinone is renally cleared 5

Zerbaxa (Ceftolozane/Tazobactam) Home Infusion (J0695, S9500)

Medical Necessity Clearly Established

Zerbaxa home infusion therapy is medically necessary for this patient with documented recurrent pseudomonal bacteremia and MRSE bacteremia requiring prolonged antibiotic therapy. [@case documentation@]

The clinical documentation demonstrates:

• Recurrent bacteremia: Multiple episodes of pseudomonal bacteremia (dates documented) and MRSE bacteremia [@case documentation@]
• Complicated infection sources: Possible seeded sources including T8-T9 osteomyelitis/discitis, IJ thrombus, and ICD hardware [@case documentation@]
• Sensitivity confirmation: Blood cultures from documented dates showed sensitivity to Zerbaxa [@case documentation@]
• Infectious disease consultation: ID team recommended continuing Zerbaxa 1.5g IV q8h plus doxycycline for chronic suppression [@case documentation@]
• Lower level of care appropriate: Patient stable enough for home infusion rather than continued hospitalization [@case documentation@]

Guideline Support for Home Antibiotic Therapy

Home antibiotic infusions are appropriate when a patient has been diagnosed with an infection requiring further treatment at a lower level of care, and homebound status is not required for home infusion therapy. [@case documentation - AHH Internal Exceptions list@]

Clinical Algorithm for Antibiotic Home Infusion

Home antibiotic therapy is indicated when:

1. Active infection documented by positive cultures with identified organism [@case documentation@]
2. Sensitivity testing confirms appropriate antibiotic choice [@case documentation@]
3. Clinical stability achieved allowing discharge from acute care [@case documentation@]
4. Prolonged therapy required beyond what is feasible in hospital setting [@case documentation@]
5. Vascular access established and maintained safely [@case documentation@]
6. Patient/caregiver education completed for home management [@case documentation@]

All criteria are met in this case.

Diagnosis Code I50.22 Appropriateness

While I50.22 (chronic systolic congestive heart failure) may not be explicitly listed in some payer criteria for home infusion, it is the appropriate primary diagnosis given the patient's underlying condition and the clinical context requiring both therapies. [@case documentation@]

Multi-Diagnosis Clinical Picture

The complete clinical picture includes:

• I50.22: Chronic systolic heart failure (primary cardiac condition requiring milrinone) [@case documentation@]
• A41.9: Sepsis/bacteremia (indication for Zerbaxa) [@case documentation@]
• R78.81: Bacteremia (documented in prior authorizations) [@case documentation@]
• M46.2 (implied): Osteomyelitis/discitis T8-T9 (complicating infection) [@case documentation@]

The diagnosis code I50.22 is appropriate as the primary diagnosis because it represents the patient's chronic condition requiring ongoing management, while the infectious complications require concurrent antibiotic therapy. Both therapies address different but coexisting medical problems in the same patient.

Payer Criteria Considerations

The case notes indicate CPB criteria were met for milrinone infusion codes (S9348, J2260, S9500) with the caveat that I50.22 was not specifically listed. However:

• Medical necessity is not solely determined by diagnosis code lists but by clinical appropriateness [@case documentation@]
• The documented clinical scenario of advanced heart failure requiring palliative inotropic support meets the intent of coverage criteria 2, 3, 4
• The AHH Internal Exceptions list allows nurse certification for antibiotic infusions using nursing judgment when infection is diagnosed and requires treatment at lower level of care [@case documentation@]

Conclusion on Medical Necessity

Both therapies were medically necessary:

1. Milrinone: Palliative inotropic therapy for end-stage heart failure with progressive LV dysfunction (LVEF 27%) in a patient previously responsive to milrinone, meeting criteria for destination/palliative therapy 1, 3, 4

2. Zerbaxa: Treatment of documented recurrent pseudomonal and MRSE bacteremia with complicated infection sources (osteomyelitis, ICD hardware, vascular thrombus) requiring prolonged IV antibiotic therapy, with organism sensitivity confirmed and infectious disease consultation supporting the regimen [@case documentation@]

The 15 visits over the documented date range are consistent with the need for ongoing monitoring, medication administration, and assessment of response to both therapies in the home setting. 3, 4