Novel liquid-gas exchange technique to reduce postoperative pneumocephalus in chronic subdural hematoma.

OBJECTIVE

Postoperative pneumocephalus after burr hole drainage for chronic subdural hematoma (CSDH) may delay brain re-expansion and worsen prognosis. This study assessed the "liquid-gas exchange" technique's value in reducing intracranial air and promoting early brain re-expansion.

METHOD: A retrospective analysis included 147 CSDH patients who underwent single burr hole drainage (Jan 2021-Jul 2025). They were divided by intraoperative air evacuation: new technique group (n = 66) and conventional group (n = 81). Baseline characteristics (gender, age, medical history, antiplatelet/anticoagulant use, hematoma volume, bilaterality) were comparable (all P > 0.05). Surgical position, anesthesia type, postoperative pneumocephalus volume, symptomatic pneumocephalus, 1-week residual cavity volume, complications, and 3-month recurrence were compared.

RESULT: On postoperative day 1, pneumocephalus volume was lower in the new technique group (15.2 ± 8.1 mL vs. 32.5 ± 18.3 mL, P < 0.001). Tension pneumocephalus occurred in 12 conventional group cases (none in the new group, P = 0.003). At 1 week, residual cavity volume was smaller in the new group (24.5 ± 12.8 mL vs. 45.2 ± 18.5 mL, P < 0.001).

COMPLICATIONS: 1 epilepsy case/group; no infections; 2 subdural bleeding cases (conventional group only, P = 0.643). At 3 months, 3 conventional group cases recurred (none in the new group, P = 0.115).

CONCLUSION

The "liquid-gas exchange" technique reduces postoperative pneumocephalus (especially symptomatic cases) and 1-week residual cavity volume, promoting early brain re-expansion and better prognosis, with high clinical value for wider use.