Advancing an epidural catheter 10 cm then retracting it 5 cm is no more effective than advancing it 5 cm

Study Objective: To determine whether threading an epidural catheter 10 cm then retracting it 5 cm affects its intravascular placement and paresthesias. Design: Prospective randomized study. Setting: Labor and Delivery Unit, University Medical Center. Patients: Eighty parturients. Interventions: All patients received epidural anesthesia. Patients were randomized to 1 of 2 groups: threading the epidural catheter 5 cm (5-cm group) or threading the epidural catheter 10 cm and retracting 5 cm (10-cm group). In the 10-cm group, the epidural catheter was threaded 10 cm and pulled back 5 cm. In the 5-cm group, the epidural catheter was threaded 5 cm. Measurements and Main Results: Placement of the epidural catheter intravascularly, the presence of a paresthesia, and bilateral sensory levels were measured. There was no difference in the frequency of intravascular placement between 10- and 5-cm groups, 10.2% vs 7.5%, respectively. Although not statistically significant, there was a trend toward a higher frequency of paresthesia in the 10-cm group, 15.4% vs 7.5%, and a lower frequency of uneven sensory levels in the 10-cm group, 15% vs 2.6%. Conclusions: There is no clear clinical benefit or disadvantage to threading an epidural catheter 10 cm into the epidural space then withdrawing it 5 cm. Further study is warranted.