Comparison of 25 and 27 Gauge Needle in Spinal Anesthesia Learning Curve for Anesthesia Residency Training
Somrat Charuluxananan MD, MSc, FRCAT*, Oranuch Kyokong MD, MSc, FRCAT*, Pornthep Premsamran MD, FRCAT**
Affiliation : * Department of Anesthesiology and Clinical Epidemiological Unit, Faculty of Medicine, Chulalongkorn University ** Department of Anesthesiology, Faculty of Medicine, Chulalongkorn University
Background and Rationale: Size of spinal needle may be a factor which influences the success rate of spinal
anesthesia.
Objectives : To compare learning curves of using 25G and 27G quincke spinal needle for spinal anesthesia.
Setting : Department of Anesthesiology, Faculty of Medicine, Chulalongkorn University and King
Chulalongkorn Memorial Hospital.
Design : Prospective randomized control trial.
Materials and Methods : Ten new first year anesthesia residents were randomized to 2 groups: Group I (n = 5)
used 25G Quincke spinal needle, Group II (n = 5) used 27G Quincke spinal needle to perform 200 consecutive
cases of spinal anesthesia. Number of success and failure was recorded by each individual resident anony-
mously. The learning curves of plotted by cumulative sum of success rate revealed an initial rapid improvement
of success during the first 20 cases in both groups. The overall success rate of group I was 84% (95CI, 66.5-
100) and group II was 87% (95%CI, 61.5-100); p = 0.89. The widest difference between the 2 learning curves
at 20 attempts intervals was at the twentieth attempts with a success rate of 76.0% VS 65.0% in group I and
group II respectively; p = 0.54.
Conclusion : The learning curves of spinal anesthesia using 25G and 27G Quincke spinal needle showed
rapid improvement of success rate at the first 20 spinal block and high overall success rate with no significant
difference between the groups.
Keywords : Anesthesia, Spinal anesthesia, Learning curve, Training, Needle size
