Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of August 10, 2026.
NPIDirectory

Joseph W Hassler, CRNA

Individual provider Certified Registered Nurse Anesthetist · NPI 1881932960

Joseph W Hassler, CRNA is registered under Certified Registered Nurse Anesthetist (CRNA) in Washington, Missouri. Qualified in 2007, 19 years ago. Practices with Western Anesthesiology Associates Inc, a 254-clinician group, works from 2 locations and accepts Medicare assignment. Licensed in Missouri.

Years since qualifying
19
Licensed in
MO
In the registry since
2013
What do these letters mean?
CRNA — Certified Registered Nurse Anesthetist
An advanced practice nurse who administers anaesthesia.

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Practice location Address checks out

901 E 5th St
Washington, MO 63090-3127
Phone: (636) 239-8000
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Additional practice locations (1)

  • 751 Sappington Bridge Rd, Sullivan, MO 63080-2354 — (573) 468-1343

Specialties & licences

Certified Registered Nurse Anesthetist (primary) Taxonomy 367500000X · Licence 2013001823 (MO)

Record details

NPI number1881932960
Entity typeIndividual (Type 1)
GenderMale
Credentials CRNA
Sole proprietorNo
NPI enumeratedJanuary 23, 2013
Last updated in NPPESNovember 5, 2021
Certification dateNovember 5, 2021

Medicare enrollment

From the CMS Doctors & Clinicians file — this clinician is enrolled in Medicare.

Medicare specialtyCERTIFIED REGISTERED NURSE ANESTHETIST (CRNA)
Medical schoolOTHER
Graduated 2007 (19 years in practice)
Group practice Western Anesthesiology Associates Inc — 254 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount

Medicare patients and services, 2024

From the CMS Medicare Physician & Other Practitioners file for calendar year 2024. It counts Original Medicare patients only, so a practice that mostly sees Medicare Advantage or privately insured patients looks smaller here than it is.

Medicare patients75
Services billed 84 a service is one billed item, such as a visit, a test or a procedure
Average patient age73

Dollar amounts are not shown. What Medicare pays a practice is gross billings, before staff, premises and tax and including the cost of any drugs it administers, so it is not what a clinician earns.

Payments from drug and device companies, 2025

Drug and device makers are required by federal law (the Physician Payments Sunshine Act) to report what they pay or give to clinicians, and CMS publishes the reports as Open Payments. This is the 2025 program year. A report is a record of a payment, not an allegation of anything, and many are small items such as meals. Only general payments are listed here; research payments and ownership or investment interests are reported separately by CMS and are not shown.

Food and Beverage $94 3 payments · a meal or drink at a meeting or visit, not a fee

Each amount is the sum of what companies reported for that kind of payment in 2025, rounded to the dollar. Not all of it is income to the clinician: a meal is not a fee, a charitable contribution goes to a charity, and a royalty or an acquisition payment is not a salary.

Check a report, or dispute one, at the source in CMS’s own tool, Open Payments. Corrections go through CMS’s dispute process. This site removes a home address on request and asks for no proof, because that is privacy; it will not remove an accurate payment report on request, because that is a statutory public disclosure.

Practises at

Facilities the CMS Facility Affiliation file lists for this clinician.

  • Mercy Hospital Washington Hospital · Washington, MO

Colleagues at Western Anesthesiology Associates Inc

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 254 clinicians in the practice; 12 are shown here.

Other providers in Washington