Vivian Lam, MD
NPI 1629421144 · Critical Care Medicine (Internal Medicine) Physician · Oak Lawn, IL
Enrolled with Medicare as Practitioner - Emergency Medicine · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Vivian Lam, MD is a Critical Care Medicine (Internal Medicine) Physician provider in Oak Lawn, IL (NPI 1629421144).
Provider details
- NPI number
- 1629421144
- Entity type
- Individual
- Primary specialty
- Critical Care Medicine (Internal Medicine) PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Female
- Sole proprietor
- Yes
- License
- 036.161275 (IL)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure28% of score
9 yrs in NPPES registry
- Profile completeness28% of score
100% of core fields populated
- Practice footprint17% of score
2 documented practice locations
- Medicare service volume (vs. specialty peers)28% of score
205 Medicare services, 2024 (ranked within specialty)
Medicare volume is ranked against active providers in the same specialty. Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our methodology.
What this provider does (Medicare)
Based on Medicare fee-for-service claims, 2024; not all care is captured.
| Service (HCPCS) | Medicare services | Typical Medicare-allowed (2024) |
|---|---|---|
| Critical Care, First 30-74 Minutes99291 | 186 | $218 |
| Subsequent Hospital Care With Moderate Levelof Medical Decision Making, If Using Time, at Least 35 Minutes99232 | 19 | $81 |
Typical Medicare-allowed amounts for these services range $81–$218 (2024). The Medicare-allowed amount is what Medicare recognizes for a service under fee-for-service — a reference figure for 2024, not a price quote and not what you would be billed. Medicare Part B covers roughly an eighth of all NPIs (65+ skew); services with fewer than 11 beneficiaries are suppressed by CMS. Source: CMS Medicare Physician & Other Practitioners, by Provider & Service.
Practice location
Mailing address
Additional practice locations (1)
- 1500 E. Medical Center Dr.Ann Arbor, MI 48109Phone: (734) 763-7919
Registry dates
- Enumerated
- 2016-07-20
- Last updated
- 2024-11-06
- Certified
- 2024-11-06
Frequently asked questions
- What is Vivian Lam's NPI number?
- Vivian Lam's National Provider Identifier (NPI) is 1629421144, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Vivian Lam's specialty?
- Vivian Lam is listed in the NPPES registry with a primary specialty of Critical Care Medicine (Internal Medicine) Physician (Allopathic & Osteopathic Physicians).
- Where is Vivian Lam located?
- Vivian Lam's practice location on file with NPPES is 4440 W 95th St, Oak Lawn, IL 60453-2600.
- What is Vivian Lam's phone number?
- The practice phone number listed in the NPPES registry for Vivian Lam is (708) 684-8000.
- Does Vivian Lam accept Medicare?
- Vivian Lam is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Vivian Lam's NPI active?
- Yes — Vivian Lam's NPI (1629421144) is active in the NPPES registry as of the last update on 2024-11-06.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.