Effects of Instrument-Assisted Constant-Speed Injection Versus Manual Injection on Pain From Large-Volume Subcutaneous Injection of Pertuzumab and Trastuzumab in Breast Cancer: A Randomized, Self-Controlled Study

Research Background:Subcutaneous injection is an important route of administration in targeted therapy for breast cancer, but injection pain affects patients' treatment experience. Fluctuations in injection speed during traditional manual push may be one of the factors exacerbating pain, whereas machine-driven injection can provide a constant flow rate, theoretically reducing pain; however, high-quality evidence is lacking.

Research Objective:To compare the difference in pain intensity between instrument constant-speed injection and manual injection in breast cancer patients receiving subcutaneous injection of pertuzumab and trastuzumab.

Research Methods:A randomized self-controlled design is used, with data analysis performed using paired t-tests. The study plans to enroll 40 female breast cancer patients. Each patient receives two injection methods across two treatment cycles: instrument constant-speed injection (medical infusion pump, 2 mL/min) and manual injection (a nurse uses a stopwatch to time and simulates the injection pump speed of 2 mL/min). The order of injection methods is randomly assigned by drawing lots (the injection method for the first cycle is randomly drawn, and the method for the second cycle is naturally the alternative method). The primary outcome is the patient's most severe pain during injection, measured immediately after injection using the Numerical Rating Scale (NRS, 0-10). Secondary outcomes include injection site reactions, patient satisfaction, nurse fatigue (Borg CR10 scale), patient preference, and safety indicators.

Research Significance:The results of this study will provide high-level evidence for selecting comfortable and efficient subcutaneous injection techniques in clinical practice, thereby improving patients' treatment experience.