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PROVIDER PROFILE · NPI 1043336258

John O'brienA.P.R.N.

PRACTICEWCHNSee all providers at this practice →
Certified Registered Nurse Anesthetist (CRNA)Danbury, CTI
CROSS-REFERENCE

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MEDICARE UTILIZATION · PART B · 2024
Total beneficiaries
96
Unique beneficiaries
—
Total services
97
Distinct HCPCS
4
Medicare payment
$8K
Peer benchmark
Q1
Q2
Q3
Q4
Q5
Total Medicare services vs. 679 Certified Registered Nurse Anesthetist (CRNA) providers in CT — above median (cohort median 102).
PRESCRIBING · PART D · 2024
No data available for this provider in 2024.
QUALITY · MIPS · 2024
No data available for this provider in 2024.
INDUSTRY PAYMENTS · OPEN PAYMENTS · 2024
No data available for this provider in 2024.
REFERRAL NETWORK

Where John O'brien's patients come from & go

Directional shared-patient flow from Medicare claims — who sends patients to this provider (inbound) and where this provider's patients go next (outbound). 4 inbound referrers · 9 outbound destinations.

Receives referrals from
Inbound — who sends patients here
PhysicianPatientsVisits
Quest Diagnostics Llc
Clinical Laboratory · Wallingford, CT
1618
Robert Deveney
Orthopedic Surgery · Danbury, CT
1630
Jeffrey Schmierer
Cardiology · Danbury, CT
1216
Douglas Henshaw
Orthopedic Surgery · Danbury, CT
1113
Refers patients to
Outbound — where patients go next
PhysicianPatientsVisits
Western Connecticut Orthopedic Surgical Center Llc
Ambulatory Surgical Center · Danbury, CT
8992
DANBURY HOSPITAL65115
Allan Grunberg
Anesthesiology · Washington Depot, CT
4143
Scott Frieary
Anesthesiology · Greenville, NC
4040
Guisseppi Digiovanni
Orthopedic Surgery · Danbury, CT
3577
Robert Deveney
Orthopedic Surgery · Danbury, CT
2127
Ronan Romero
Anesthesiology · Danbury, CT
1919
Antonio Paz
Interventional Pain Management · Brookfield, CT
1212
Douglas Henshaw
Orthopedic Surgery · Danbury, CT
1118
Source: CMS Physician Shared Patient Patterns (30-day window, Medicare FFS). Direction = a beneficiary seen by the first provider, then the second, within 30 days; a proxy for referral, not a documented referral. Pairs with fewer than 11 shared beneficiaries are suppressed.