Effects of Hyperbaric Oxygen Therapy on Postoperative Surgery

1. The core mechanism of HBOT in promoting postoperative recovery

Enhancing tissue oxygen supply and antioxidant defense

Surgical trauma is often accompanied by local microcirculatory disorders and tissue hypoxia. HBOT can increase the plasma dissolved oxygen concentration by 20 times at 2-3 atmospheres, directly improving the energy metabolism of hypoxic tissues. Studies have shown that HBOT can upregulate the activity of antioxidant enzymes (such as superoxide dismutase) and reduce the damage of reactive oxygen species (ROS) to mitochondria, thereby accelerating the resolution of postoperative inflammation.
​​Regulate inflammation and immune response​​
HBOT reduces postoperative systemic inflammatory response syndrome (SIRS) by inhibiting the release of proinflammatory factors (such as TNF-α, IL-6) and promoting the secretion of anti-inflammatory factor IL-10. Animal experiments have confirmed that HBOT can reduce macrophage infiltration and shorten wound healing time by more than 30%.
​​Promote angiogenesis and tissue repair​​
The activation of hypoxia-inducible factor-1α (HIF-1α) is one of the core pathways of HBOT. HIF-1α promotes capillary angiogenesis and improves local blood supply after surgery by stimulating the expression of vascular endothelial growth factor (VEGF). Clinical data show

that HBOT can increase the survival rate of skin transplants by 25% and reduce the risk of flap necrosis.

2. Clinical application of HBOT in postoperative complications

Postoperative infection and wound healing​​
HBOT has an auxiliary antibacterial effect on infectious postoperative complications (such as abdominal abscesses and osteomyelitis). Hyperbaric oxygen environment can inhibit the toxin production of anaerobic bacteria (such as Clostridium perfringens) and enhance the phagocytic ability of neutrophils. A multicenter study of 300 patients (Smith et al., 2022) showed that the incidence of deep infection in the HBOT group was 52% lower than that in the control group, and the wound healing time was shortened by 10 days.
​​Postoperative pain and dysfunction

HBOT can significantly relieve postoperative chronic pain by regulating the levels of serotonin and dopamine in the central nervous system. A randomized controlled trial after joint replacement found that the visual analog pain score (VAS) of patients in the HBOT group decreased by 40% compared with the control group, and the improvement of joint range of motion was more significant.
​​Organ function protection

HBOT can reduce ischemia-reperfusion injury after cardiothoracic and hepatobiliary surgery. For example, HBOT improves liver function recovery after partial liver resection by reducing the expression of hepatocyte apoptosis markers (such as caspase-3). In addition, HBOT can also reduce the consumption of alveolar surfactant and prevent postoperative acute respiratory distress syndrome (ARDS).

3. Controversy and limitations

Heterogeneity of efficacy and applicable population

There are significant differences in the conclusions of current studies. For example, the benefits of HBOT for clean surgery (such as hernia repair) have not been clearly established, but it is effective for contaminated surgery (such as intestinal perforation repair). A 2023 Cochrane systematic review pointed out that HBOT is only cost-effective for specific high-risk groups (such as those with diabetes and postoperative infection), and may be over-medicalized for ordinary patients.
​​Safety risks and economic burden

HBOT may cause complications such as barotrauma and oxygen toxicity (manifested as epileptic seizures), with an incidence of about 1%-3%. In addition, the high cost of a single treatment (usually hundreds to thousands of yuan) and the need for multiple courses of treatment limit its popularity. Some countries only cover specific indications (such as gas embolism and refractory ulcers) in medical insurance.
​​Controversy over the quality of evidence

Although some clinical trials support the efficacy of HBOT, most studies have small sample sizes and insufficient blinding. For example, a meta-analysis of abdominal surgery (2021) pointed out that the difference between the HBOT group and the control group may be interfered by confounding factors (such as underlying diseases), and a larger RCT is needed for verification.

4. Future Directions and Clinical Recommendations
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Precision Application Strategies

In the future, it is necessary to screen the beneficiary population through biomarkers (such as HIF-1α levels, microcirculation imaging) and optimize treatment parameters (pressure, course of treatment). For example, for patients after cancer surgery, it is necessary to weigh the immunomodulatory effect of HBOT against the risk of tumor recurrence.
​​Combined Therapy and Technological Innovation

The combined application of HBOT with stem cell therapy and bioengineered dressings may enhance the efficacy. In addition, the development of portable hyperbaric oxygen equipment (such as normal pressure hyperoxia chamber) may lower the threshold for treatment.

5. Conclusion

Hyperbaric oxygen chamber therapy improves postoperative tissue repair and functional recovery through multi-target mechanisms, and shows unique value in the fields of infectious complications and chronic pain management. However, its clinical application must strictly follow the indications to avoid waste of resources. Future research should focus on stratified treatment strategies and cost-effectiveness analysis to promote the transformation of HBOT from experimental intervention to standardized treatment.