Adaptive Fluidics With Dynamic Fluid Infusion Boosts Efficiency Of Phacoemulsification: Results Of A Randomized Controlled Study

To compare the key phacoemulsification attributes of fluid volume and ultrasound parameters between variable infusion pressure system (adaptive fluidics) and gravity-fed fixed infusion pressure system. 

An interventional randomized controlled trial. 

An interventional randomized controlled trial. 108 cataract surgeries were randomized in 1:1 into Group 1, in a variable infusion pressure system (that maintains fluidics stability within the eye by dynamic infusion linked to real-time vacuum levels), and in Group 2, with a gravity-fed fixed infusion pressure system. In both groups, the same venturi-based phaco machine was employed with differently specified disposable cassettes, operated by a single surgeon with identical ultrasound and vacuum settings. Outcomes of used fluid volume within the eye, average phaco power (U/S AVE), absolute phaco time (APT), and elapsed phaco time (EPT) were analyzed. 

The baseline parameters of cataract grades and axial length were comparable between groups (p=0.442, 0.605). The mean fluid level in Group 1 was 90.2+/-19 ml against Group 2 which is 129+/-44 (p<0.0001). The mean vacuum in Groups 1 and 2 were 311.4 & 322.4mm Hg (p=0.115). U/S AVE was comparable between groups (18% in Group 1, 20.4% in group 2; p=0.087), however, EPT was significantly greater in Group 2 (9.5+/-4.9 sec) compared to Group 1 (5.3+/-3.6 sec, p<0.0001). The total phaco energy delivered into the eye, represented by APT in Group 1 was significantly less, 21.79+/-8.65 sec compared to Group 2, which is 31.27+/-7.3 sec (p<0.0001). 

Real-time vacuum-linked dynamic fluid infusion in venturi-based phaco systems uses lesser fluid volume and phaco energy within the eye, compared to gravity-fed fixed infusions, which could translate clinically as less traumatic and possibly more endothelium friendly.