The Effect of ShotBlocker on Pain and Patient Satisfaction for Spinal Anesthesia: A Randomized Trial

Abstract

BACKGROUND: During spinal anesthesia, patients may experience pain and discomfort associated with dermal puncture. It may also cause involuntary movement, which often disturbs the patient’s posture thus affecting the success of spinal anesthesia. Different methods have been studied to cope with needle-related pain. “ShotBlocker” is a flexible, plastic, U-shaped device, which has several blunt points. It is suggested that blunt points provide a nonnoxious physical stimulation and inhibit the transmission of injection pain. OBJECTIVES: The purpose of this study was to examine the effectiveness of the ShotBlocker for dermal puncture pain during spinal anesthesia. STUDY DESIGN: Prospective randomized trial. SETTING: University hospital, operating room. METHODS: Ninety-four patients aged 18 to 65 years with physical status American Society of Anesthesiologists (ASA) I or II scheduled for elective surgery under spinal anesthesia were randomly assigned to either a ShotBlocker (n = 47) or control group (n = 47). In the ShotBlocker group, lumbar punctures were performed with the application of ShotBlocker. Needle-associated pain score and patient satisfaction were assessed by the patient, immediately after completion of the spinal anesthesia using a 10-cm Visual Analog Scale (VAS) and a 5-point Likert scale for satisfaction. Patients were also closely observed for symptoms of discomfort such as spontaneous vocalization and involuntary movement. RESULTS: A total of 88 patients completed the study. There was no significant difference in VAS scores, patient satisfaction, or procedure time between groups (P > 0.05). Spontaneous vocalization did not occur in both groups. However, incidence of unintentional movement during dermal puncture was higher in the control group (6.8% vs. 31.8%; P < 0.05). LIMITATIONS: Study was conducted in a single-center with a relatively small population of patients. Only the attending anesthetist collecting data was blinded to the procedure. Patients older than age 65 years were also excluded from the study, thus our results cannot be generalized. CONCLUSIONS: ShotBlocker did not show any advantage on VAS scores but decreased the incidence of unintentional movement during dermal puncture. KEY WORDS: Spinal anesthesia, pain, ShotBlocker, needle, pin-prick pain, dermal puncture, neuraxial block, regional, needle phobia, lumbar puncture