An analysis of the efficacy of two different retrobulbar anesthesia for micro-invasive vitrectomy

Objective To evaluate the efficacy of micro-invasive vitrectomy with two retrobulbar anesthetic methods.Methods Clinical case-control study,120 patients scheduled for 3-port pars plana vitrectomy using 23-gauge instrumentation combined with 25-gauge infusion were randomly divided into two groups according to anesthetic method.Patients in group A were anesthetized with an injection of narcotic through temporal side; patients in group B received the traditional retrobulbar nerve block.Main outcome measures included Visual analogue scale,immobilization score,complications,vital signs observation,the surgeon and patient satisfaction etc.Results The differences of Visual analogue scale (F =319.1,P ＜0.05) and immobilization score (F =1267.9,P ＜0.05) between group A and group B were statistically significant.Visual analogue scale of group A and group B was different during anaesthetizing (t =-6.4,P ＜0.05) and group A (3.3±1.9) ＜group B (5.5±2.0).The differences of immobilization score at 2 minutes (t =-5.2,P ＜0.05) and 4 minutes (t =-3.9,P ＜0.05) were statistically significant,and group A (7.1±2.2) ＜group B (9.1±2.0) at 2 minutes; group A (3.8±2.0) ＜group B (5.3±2.1) at 4 minutes respectively.The differences of blood pressure between group A and group B were statistically significant (t =-4.7,P ＜0.05) with group A (15.1±0.8) ＜group B (15.3±1.2); respiratory rate in group A (109±7) was lower than that in group B (123±9)with statistical significance (t =-5.3,P ＜0.05).The time of reaching immobilization criterion was shorter (t =-3.1,P ＜0.05) in group A.The differences of the satisfactory degree of surgeon (F =0.03,P ＜0.05) and patient (F =0.01,P ＜0.05) between group A and group B were statistically significant.Oronasal numbness was found in 2 patients from group A,and temporary blackouts was found in 1 patient from group B.Two patients in group A and 7 patients in group B required additional anesthesia ten minutes after the first narcotic,and 6 patients in group B required that during surgery time.No anesthesia-related complications occurred in this study.Conclusions Anesthesia via temporal side for micro-invasive vitrectomy shows good clinical results.It is easier,requires lesser times of injection,gains higher satisfactory degree of surgeon and patient compared with traditional retrobulbar nerve block.Further studies are needed to explore its functions. Key words: Retrobulbar anesthesia; Micro-invasive vitrectomy; Visual analogue scale; Immobilization