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Certified Registered Nurse Anesthetist (CRNA)

Elizabeth S. Grenier

Works at hospitals in Portland, ME · Maine

Summary

Elizabeth S. Grenier is a nurse anesthetist at 155 Rover River Pkwy, Portland, ME 04102. Phone: (207) 879-3000. Accepts Medicare assignment. In 2024, Elizabeth S. Grenier had 72 Original Medicare patients and 73 services. NPI 1427549997. Source: CMS National Downloadable File, updated October 2, 2026; CMS Facility Affiliation Data, updated October 2, 2026; CMS Medicare Physician & Other Practitioners, data year 2024.

  • Specialty: Nurse anesthetist (Medicare lists Certified Registered Nurse Anesthetist (CRNA))
  • Address: 155 Rover River Pkwy, Portland, ME 04102 · Directions (2 more locations)
  • Phone: (207) 879‑3000
  • Medicare: Accepts Medicare assignment
  • Hospital: Northern Light Mercy Hospital
  • Group practice: Mercy Hospital
  • School: graduated 2019
  • Gender (as listed): Female

From official Medicare data

This page shows what Medicare's official clinician data says about Elizabeth S. Grenier, joined by NPI number (data updated October 2, 2026). It is not a recommendation or a rating. Call the office or hospital to confirm before you go.

In a medical emergency, call 911.

Quick answers

Does Elizabeth S. Grenier accept Medicare assignment?
Yes. Medicare's clinician data says Elizabeth S. Grenier accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of October 2, 2026. Ask the office to confirm before your visit.
How many Medicare patients does Elizabeth S. Grenier see?
In 2024, CMS data shows 72 Original Medicare patients and 73 services for Elizabeth S. Grenier. This counts Original Medicare only and measures volume, not quality.
What is Elizabeth S. Grenier's NPI number?
1427549997. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Medicare activity in 2024

Official CMS public-use data for Elizabeth S. Grenier, data year 2024 (released May 21, 2026). It covers Original Medicare (fee-for-service) patients only, not Medicare Advantage or other insurance. It shows volume, not quality or outcomes. CMS hides any count of 10 or fewer patients.

Original Medicare patients72
Services billed to Medicare73
Different services or procedures27
Participating Medicare providerYes
Average age of these patients73

Chronic conditions among these patients

Share of this clinician’s Original Medicare patients with each condition, as published by CMS (it describes the patients, not the care given).

  • High blood pressure71%
  • High cholesterol67%
  • Arthritis60%
  • Anxiety33%
  • Cancer (breast, colorectal, lung, prostate, endometrial or leukemia/lymphoma)32%
  • Chronic kidney disease25%

Hospitals where Elizabeth S. Grenier works

Medicare's Facility Affiliation Data lists Elizabeth S. Grenier at these hospitals (updated October 2, 2026). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians. Star rating and emergency services: Hospital General Information (CMS), data updated October 26, 2026.

Practice locations

Addresses where Elizabeth S. Grenier is enrolled with Medicare (CMS data updated October 2, 2026).

Group practices

Medicare enrollment lists Elizabeth S. Grenier as a member of this group (CMS data updated October 2, 2026).

  • Mercy Hospital301 clinicians in the group

Specialties

Find other clinicians: Certified Registered Nurse Anesthetist (CRNA), Maine →

Other nurse anesthetists in Portland

Clinicians with the same Medicare primary specialty in Portland, ME — not a recommendation.

All nurse anesthetists in Portland →

Other clinicians in Mercy Hospital

Medicare enrollment lists these clinicians in the same group practice — not a recommendation.

Clinician information

Graduation year2019
Gender (as listed)Female
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1427549997
CorrectionsReport an error or suggest an update →

Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.

Sources

  1. Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated October 2, 2026, retrieved October 29, 2026
  2. Hospital General Information — CMS, data updated October 26, 2026, retrieved November 13, 2026
  3. National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
  4. Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
  5. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  6. Medicare Care Compare — official Medicare tool to look up clinicians