Reduced injection pressures using a compressed air injection technique (CAIT): an in vitro study.

Area of Science:

• Anesthesiology
• Neurosurgery
• Medical Devices

Background:

• High injection pressures are linked to intraneural injection and neurological injury in animal models.
• A safe injection pressure limit of 1,034 mm Hg has been suggested to prevent nerve damage.

Purpose of the Study:

• To evaluate if a compressed air injection technique (CAIT) can maintain injection pressures below 1,034 mm Hg in an in vitro setting.
• To compare CAIT with the traditional "syringe feel" method for pressure generation.

Main Methods:

• 30 anesthesiologists performed saline injections using 30 mL syringes and 22-gauge needles in a semiclosed system.
• Injection pressures were measured for 60 seconds using the "syringe feel" method and CAIT.
• CAIT involved compressing 10 mL of air above the saline to 5 mL before and during injection.

Main Results:

• All 30 anesthesiologists using CAIT maintained pressures below 1,034 mm Hg.
• 29 of 30 anesthesiologists exceeded 1,034 mm Hg using the "syringe feel" method.
• Mean pressure with CAIT was significantly lower (636 mm Hg) than with the "syringe feel" method (1,378 mm Hg).

Conclusions:

• CAIT effectively limits injection pressures below the 1,034 mm Hg threshold in an in vitro model.
• Further animal and clinical studies are required to validate CAIT for real-time pressure monitoring and its impact on nerve injury prevention.
• CAIT shows potential to enhance the safety of peripheral nerve blocks.