Sub-Tenon Block: A Learning Curve of 100 Cases

Abstract

This study measures the learning curve for accomplishing sub-Tenon blocks for ophthalmic surgery applicable to anaesthetists skilled in peribulbar techniques. We defined criteria for a good block in terms of chemosis, subconjunctival haemorrhage, globe movement and the need for additional peribulbar block. The overall success rate, by our definitions, was 72% and 56% for the two operators. The overall requirement for an additional peribulbar block was 10%. The rate of additional blocks and reduction in globe movement reached a plateau after about 60 procedures for both operators. The rates of chemosis (6% and 12% overall) and subconjunctival haemorrhage (6% and 12% overall) did not trend with increased experience. The results applied to both a cataract and a vitreo-retinal surgery casemix.

Assessment of the learning curve of peribulbar blocks using the Learning-Curve Cumulative Sum Method (LC-CUSUM): an observational study

“…In the only study retrieved from a comprehensive literature search, Clarke and colleagues described the sub-Tenon block learning curves of two anesthesiologists experienced in peribulbar anesthesia using the success rates at every 20 blocks in a sequence of 100 blocks performed by each anesthesiologist to assess learning, who stabilized performance after 60 blocks. 11 Thus, to the authors’ best knowledge, this may be the first study describing novice anesthesia residents' peribulbar anesthesia learning curve.…”

Adverse Events Associated with Regional Ophthalmic Anaesthesia in an Australian Teaching Hospital

“…Therefore care needs to be taken with case selection, consent and degree of supervision until adequate case numbers are achieved. A previous study suggested that improvement in technique continued over the first 60 STB performed 8 .…”

Revisiting transconjunctival sutureless 25‐gauge vitrectomy: still worthwhile?

“…A posterior sub-Tenon injection of 1% ropivacaine with 15 units/mL of hyaluronidase (mean volume 5 mL) was given for local anaesthesia. 8 All 25G surgical procedures were performed using the Millenium (Baush & Lomb, Rochester, NY, USA) 25G transconjunctival sutureless vitrectomy system. The trocars were placed through the conjunctiva and the sclera by shifting the conjunctiva sidewards.…”