Big ones 14-16 mostly for drawing up drugs etc as low resistance. Needles up to 14g are also used as part of cannula to insert IV access - bigger ones over 18G only really used in cases where you need to give large volumes of liquid quickly eg during anaesthetics or if you’re seriously unwell/in shock.
Big ones 14-16 mostly for drawing up drugs etc as low resistance. Needles up to 14g are also used as part of cannula to insert IV access - bigger ones over 18G only really used in cases where you need to give large volumes of liquid quickly eg during anaesthetics or if you’re seriously unwell/in shock.