Bunkerhill’s $55M bet: making AI work inside real hospitals
Bunkerhill Health has closed a $55 million Series B round to push its agentic AI platform, Carebricks, deeper into the messy reality of working hospitals. The round includes continued backing from Sequoia Capital, Felicis, Optum Ventures, and Y Combinator, with Khosla Ventures joining as a new investor.
That last name matters. Vinod Khosla has watched plenty of healthcare AI projects die in pilot purgatory — models that dazzled in research papers but never touched a patient chart. His firm’s participation signals something: Bunkerhill claims to have cracked the hardest part of healthcare AI, which is getting a health system to actually run the software in production.
The problem Carebricks tries to solve
US healthcare spending hit $5.3 trillion in 2024, according to the Centers for Medicare & Medicaid Services. Meanwhile, labor shortages keep squeezing providers. Hospitals have poured money into documentation systems meant to lighten the load on clinicians. Bunkerhill’s argument is that the next wave of technology spending shouldn’t just record what doctors think — it should act on those ideas.
“Medicine has advanced faster than our healthcare system’s ability to operationalise it,” said Nishith Khandwala, co-founder and CEO of Bunkerhill Health. “Every leading health system has more opportunities to improve patient outcomes than its workforce has capacity to address. We believe AI agents can help them turn more of those ideas into reality.”
What Carebricks actually does
Carebricks isn’t a fixed product. It’s a platform that lets hospitals build their own AI agents. Some agents scan cardiology imaging for early signs of heart disease and flag patients needing follow-up. Others handle prior authorizations or keep registry data current. The range extends into administrative work — the kind that rarely makes AI pitches but eats staff hours every week.
Cleveland Clinic, the University of Texas Medical Branch (UTMB), and Intermountain Health all run Carebricks today.
20 AI agents live inside one health system
UTMB offers the clearest picture of what “running it” looks like once the pilot label comes off. The system now has more than 20 agents live on Carebricks, spanning clinical care, operations, and administration, according to Dr. Peter McCaffrey, UTMB’s chief AI officer.
A coronary calcium agent that caught a heart attack before it happened
In its first month running at UTMB, a coronary calcium detection agent built on an FDA-cleared algorithm flagged a patient as being at imminent risk of a heart attack. Cardiology confirmed the risk and performed a triple bypass. UTMB’s care team credits the early detection with saving the patient’s life.
It’s a single case, not a controlled trial. Bunkerhill has published no data on false-positive rates or performance across a broader patient population over time.
Nephrology triage cuts wait times in half
A nephrology triage agent now prioritizes patients by severity, escalating urgent cases and routing others to telemedicine. UTMB reports this has cut average specialist wait times by more than 50 percent.
Lung nodule tracking improves follow-up speed
A lung nodule agent tracks incidental findings on CT scans through to the correct follow-up. UTMB cites an 80 percent faster response on urgent cases, a doubling of guideline-concordant follow-up, and a drop in manual coordinator work.
These are health system-reported operational results from live production use — not synthetic benchmark scores. That matters. It also means the numbers reflect one institution’s data conditions and staffing setup, not a guarantee that another hospital will see the same curve.
“We’ve already seen tremendous impact on patient care, and we’re only at the beginning of what becomes possible when a health system can operate with agentic AI at this scale,” McCaffrey said.
The governance question Bunkerhill can’t dodge
None of this removes the work health systems still have to do themselves. Bunkerhill says it will use the new funding to expand Carebricks into a wider range of clinical and operational use cases while building out governance, monitoring, and safeguards.
A platform that lets a nephrology department build its own triage agent also means that department owns the consequences of how that agent is tuned. Health system boards weighing a Carebricks-style deployment need answers on liability assignment, monitoring cadence, and what happens when an agent’s judgment and a clinician’s judgment disagree — before signing off on scale.
UTMB’s 20-agent footprint gives Bunkerhill a reference case few competitors can currently match. Whether that number holds up as a signal for the rest of the industry depends on how UTMB, and the other systems now running Carebricks, handle the governance side as the agent count climbs.
What the $55M buys
Bunkerhill plans to use the new capital to expand Carebricks into a wider range of clinical and operational use cases. The company also intends to build out governance, monitoring, and safeguards — the infrastructure that makes it safe for hospitals to scale agent count without running into chaos.
Vinod Khosla put it bluntly: “The bottleneck in healthcare AI was never the technology, it was getting a health system to actually run it. Bunkerhill closed that gap. They made it much, much easier to adopt AI and already have traction inside critical health systems that would take most companies years to earn.”
The question now is whether that traction scales beyond UTMB — and whether the governance framework keeps pace with the agent count.