Patients undergoing major head and neck surgery develop vitamin K deficiency during the first week of recovery, according to a 2026 prospective study of 39 patients published in the Scandinavian Journal of Clinical and Laboratory Investigation. Researchers found that vitamin K-dependent proteins Gas6 and PIVKA-II increased significantly after surgery, with PIVKA-II continuing to rise through day 6, indicating depleted vitamin K stores. This deficiency could affect blood clotting and wound healing during a critical recovery period.
When patients have major head and neck surgery to remove tumors and rebuild the area with tissue grafts, their bodies go through significant changes. According to Gram Research analysis, a new study of 39 patients found that certain vitamin K-related proteins in the blood change dramatically after surgery, suggesting the body becomes deficient in vitamin K during recovery. Vitamin K is crucial for blood clotting, controlling inflammation, and preventing cancer growth. Understanding these changes could help doctors better support patients during their healing process and prevent complications like excessive bleeding or poor wound healing.
Key Statistics
A 2026 prospective study of 39 patients undergoing head and neck free flap surgery found that Gas6, a vitamin K-dependent protein, increased significantly on postoperative days 1 and 2 compared to preoperative levels.
In the same 2026 study of 39 surgical patients, PIVKA-II, a marker of vitamin K deficiency, showed continuous increases throughout the first postoperative week, with significant elevations by day 2 that persisted through day 6.
Research reviewed by Gram Research found that head and neck surgery patients showed signs of vitamin K deficiency within 24 hours after surgery, with protein markers indicating the deficiency worsened rather than improved during the first postoperative week.
The Quick Take
- What they studied: Whether patients who have major head and neck surgery (removing cancer and rebuilding with tissue grafts) develop vitamin K deficiency during recovery
- Who participated: 39 patients undergoing extensive head and neck surgery with tissue reconstruction. All patients were tracked from surgery day through the first week of recovery.
- Key finding: Two key vitamin K-related proteins increased significantly after surgery: Gas6 jumped on days 1 and 2, and PIVKA-II continued rising through day 6, indicating the body’s vitamin K stores were being depleted
- What it means for you: If you’re having major head and neck surgery, your surgical team may need to monitor vitamin K levels and potentially provide supplements during recovery to support healing and prevent bleeding complications. Talk to your surgeon about vitamin K management as part of your recovery plan.
The Research Details
Researchers followed 39 patients who underwent major head and neck surgery where doctors removed cancerous tissue and rebuilt the area using tissue grafts (called free flaps). They measured three special proteins in the blood that depend on vitamin K to work properly: dp-uc-MGP, Gas6, and PIVKA-II. They also measured a related protein called sAxl. Blood samples were taken on the day of surgery and then on days 1, 2, and 6 after surgery.
This is called a prospective observational study, meaning researchers watched what happened to patients over time without changing their treatment. They used statistical tests to see if the protein levels changed significantly from before surgery to after surgery. The researchers hypothesized that surgery would stress the body enough to cause vitamin K deficiency.
This research approach is important because it shows real-world changes in actual patients rather than just laboratory experiments. By measuring multiple vitamin K-related proteins at different time points, the researchers could track exactly when and how the body’s vitamin K status changes after major surgery. This helps doctors understand what’s happening inside patients’ bodies during recovery.
This study has both strengths and limitations. The strength is that it measured specific, objective markers (blood proteins) in real patients undergoing actual surgery. The limitation is the small sample size of 39 patients, which means results may not apply to all patients. The study was observational, not experimental, so researchers couldn’t control all variables. However, the findings were statistically significant, meaning they’re unlikely to be due to chance.
What the Results Show
The study found clear evidence that vitamin K deficiency develops after head and neck surgery. Gas6, one of the vitamin K-dependent proteins, increased significantly on postoperative days 1 and 2 compared to before surgery. This increase suggests the body was trying to compensate for low vitamin K.
Even more striking, PIVKA-II showed a continuous increase throughout the entire study period, rising significantly by day 2 and remaining elevated through day 6. PIVKA-II is considered a marker of vitamin K deficiency—when vitamin K is low, this protein accumulates in the blood. The fact that it kept rising suggests the vitamin K deficiency was getting worse, not better, during the first week after surgery.
Interestingly, two other proteins measured (dp-uc-MGP and sAxl) did not show significant changes, suggesting that vitamin K deficiency affects some proteins more than others. This tells us that the body’s response to surgery is selective and complex.
The pattern of protein changes over time is important. The immediate increase in Gas6 on days 1 and 2 suggests the body quickly recognizes vitamin K deficiency and tries to respond. The continued rise in PIVKA-II through day 6 indicates that vitamin K stores remain depleted throughout the first postoperative week. This timeline is crucial because it shows when patients are most vulnerable and when vitamin K support might be most beneficial.
While vitamin K deficiency has been observed in other surgical patients, this is one of the first studies to specifically track vitamin K-dependent proteins in head and neck surgery patients. Previous research showed that major surgery can deplete vitamin K, but this study provides detailed measurements of exactly which proteins change and when. The findings align with what we know about how surgery stresses the body and depletes nutrients, but this research gives us a clearer picture of the vitamin K story specifically.
The study included only 39 patients, which is a relatively small group. Results might differ in larger populations or in patients with different health conditions. The study didn’t measure actual vitamin K levels in the blood, only the proteins that depend on vitamin K, so we can infer deficiency but didn’t directly measure it. The study also didn’t track whether patients who received vitamin K supplements had different outcomes, so we don’t know if supplementation would help. Additionally, all patients were undergoing similar surgery, so results may not apply to other types of surgery or medical conditions.
The Bottom Line
Based on this research, surgeons should consider monitoring vitamin K status in patients undergoing major head and neck surgery, particularly during the first week after surgery. Vitamin K supplementation may be beneficial during recovery, though this study didn’t test supplementation directly. Patients should discuss vitamin K management with their surgical team before and after surgery. Confidence level: Moderate—the findings are clear, but larger studies are needed to confirm optimal treatment strategies.
This research is most relevant to patients scheduled for major head and neck surgery, their surgeons, and anesthesiologists. It’s also important for nutritionists and recovery specialists working with surgical patients. Patients with bleeding disorders or those taking blood thinners should especially discuss vitamin K with their doctors. People having minor procedures or those without head and neck surgery don’t need to apply these findings directly.
Vitamin K deficiency appears to develop within the first 24 hours after surgery and may persist for at least a week. If vitamin K supplementation is provided, benefits for wound healing and preventing bleeding complications would likely appear within days to weeks, though this study didn’t measure outcomes. Full recovery of normal vitamin K status may take longer than the one-week study period.
Frequently Asked Questions
What happens to vitamin K levels after major head and neck surgery?
Vitamin K deficiency develops within 24 hours after head and neck surgery and worsens during the first week of recovery. A 2026 study of 39 patients found that vitamin K-dependent proteins increased significantly, indicating the body’s vitamin K stores were depleted during this critical healing period.
Why does vitamin K deficiency happen after surgery?
Major surgery stresses the body and depletes essential nutrients, including vitamin K. The body uses vitamin K rapidly for blood clotting, inflammation control, and tissue repair. The combination of blood loss, tissue damage, and increased metabolic demands during recovery depletes vitamin K stores faster than the body can replenish them.
How long does vitamin K deficiency last after head and neck surgery?
Based on a 2026 study tracking patients for one week post-surgery, vitamin K deficiency persists at least through day 6 of recovery. The study didn’t track beyond one week, so the full duration is unknown, but deficiency appears to be a significant issue during the critical early healing phase.
Should I take vitamin K supplements before head and neck surgery?
Discuss vitamin K supplementation with your surgical team before surgery. While this research shows deficiency develops after surgery, the study didn’t test whether preoperative supplementation helps. Your surgeon can assess your individual vitamin K status and recommend appropriate supplementation based on your health history.
What are the risks of vitamin K deficiency after surgery?
Vitamin K is essential for blood clotting and controlling inflammation. Deficiency after surgery could increase bleeding risk and potentially slow wound healing. However, this study measured protein changes but didn’t track actual bleeding complications, so the clinical impact remains unclear and requires further research.
Want to Apply This Research?
- If you’re recovering from head and neck surgery, track your vitamin K intake daily (through diet or supplements as prescribed) and note any signs of bleeding (unusual bruising, bleeding gums, blood in urine) or slow wound healing. Log these observations daily for the first two weeks post-surgery.
- Work with your surgical team to establish a vitamin K supplementation plan before surgery. After surgery, prioritize vitamin K-rich foods like leafy greens (spinach, kale), broccoli, and Brussels sprouts as soon as your diet allows. If prescribed vitamin K supplements, take them consistently as directed.
- During the first postoperative week, track vitamin K intake, wound appearance, and any bleeding symptoms daily. After the first week, continue monitoring weekly for the first month. Share this data with your surgical team at follow-up appointments to help them assess your recovery progress.
This research describes changes in vitamin K-dependent proteins after head and neck surgery but does not establish that vitamin K supplementation prevents complications or improves outcomes. Patients scheduled for head and neck surgery should discuss vitamin K management, supplementation, and monitoring with their surgical team before and after their procedure. This article is for educational purposes and should not replace professional medical advice. Individual vitamin K needs vary based on health status, medications (especially blood thinners), and other factors that only a qualified healthcare provider can assess.
This research translation is published by Gram Research, the science division of Gram, an AI-powered nutrition tracking app.