Actual pressure generated by various suction technique and suctioning liquid weight through endoscopic ultrasound‐guided aspiration needles

Suction pressure is one of the most important factors that determines the amount of tissue obtained during endoscopic ultrasound-guided fine needle aspiration (EUS-FNA). This study aimed to elucidate the actual suction pressure generated by various suction methods and suctioning liquid weights.We used different types of fine needles and different suction techniques, including the slow pull technique (SPT), dry suction technique (DST), wet suction technique (WST), neutralizing negative pressure technique (NNPT), and residual negative pressure technique (RNPT). We measured their actual suction pressure and weighed the amount of suctioned liquid.The actual suction pressure and the suctioning liquid weight was lower in SPT than in DST, while that of WST was the highest. In general, the actual suction pressure increased and the suctioning liquid weight decreased as the diameter of the FNA needles decreased. For the fine-needle biopsy (FNB) needles, the suctioning liquid weight of the FNB needles was significantly larger than that of FNA needles. In general, the actual suction pressure generated using RNPT was larger than that of NNPT.WST is superior to SPT and DST in the actual suction pressure and suctioning liquid weight. The diameter of the FNA needle was an important factor that affected the actual suction pressure and suctioning liquid weight. The FNB needles is superior to FNA needles in the suctioning liquid weight. Our study measured the actual suction pressure of new suction methods (NNPT and RNPT). These novel findings provide a basis for future research.