Controlled versus gravity-based irrigation in endoscopic spine surgery: pressure stability, thresholds, and safety...

Area of Science:

• Neurosurgery
• Minimally Invasive Surgery
• Surgical Technology

Background:

• Endoscopic spine surgery requires continuous irrigation for visualization and hemostasis.
• Existing irrigation systems (gravity-based, high-flow) may cause unstable pressures and neurologic risks.
• Pump-controlled irrigation offers regulated pressure but its safety and pressure behavior need further definition.

Purpose of the Study:

• To systematically review literature comparing pump-controlled versus gravity-based/high-flow irrigation in endoscopic spine surgery.
• Focus on pressure dynamics and pressure-related complications.
• Evaluate safety and efficacy of different irrigation systems.

Main Methods:

• Systematic review following PRISMA 2020 guidelines.
• Searched PubMed, Embase, Web of Science, Google Scholar (inception-Jan 2026).
• Included experimental, animal, and clinical studies reporting pressure measurements or complications; qualitative synthesis performed.

Main Results:

• Eleven studies included (retrospective, cadaveric, animal models).
• Pump-controlled irrigation showed significantly lower working-space pressures compared to gravity-based systems (12.10 vs 23.86 mmHg).
• Outflow obstruction and dural disruption are key drivers of pressure escalation, potentially leading to neurologic complications (0.52% of cases).

Conclusions:

• Irrigation generally maintains physiologic pressures if dura is intact and outflow is adequate.
• Impaired drainage and dural disruption can cause rapid, significant pressure elevations.
• Pump-controlled systems offer stable pressures, but safety depends on effective outflow and dural integrity, necessitating intraoperative vigilance.