| 摘要 |
An instrument for epidural and spinal anaesthesia has outer and inner needle assemblies. The outer assembly has a hollow needle the forward end of which is bent at an angle of about 20 DEG and has an inclined, pointed tip that makes an angle of about 10 DEG with the axis of the instrument. The needle has a hub at its rear end which is provided with a keyway on its outer surface. The inner assembly has a hollow needle that extends within the needle of the outer assembly and projects from its forward end. The inner needle also has an inclined, pointed tip that makes an angle of about 30 DEG with the axis of the instrument. The tips of the two needles lie in planes substantially at right angles to each other. At its rear end, the inner assembly has a transparent hub with a key that locates in the keyway so as to ensure correct orientation of the two assemblies. |
