When do you saline-lock orders for IV fluids?

[nursing1989]

Hi all.

I have been doing my integrative practicum on the Surgical floor at a hospital and I'm curious about orders regarding IV fluids (such as Lactated Ringers) and when you are ok to go ahead a saline-lock a patient instead of keep the fluids running. For instance, we get a lot of orders post surgery for LR at 125/hr. The order doesn't say anything about when it is ok to disconnect the patient from the fluids and keep them saline-locked. I'm curious when it is ok for a nurse to do that. Is it if the patient is able to take in oral fluids, their IV & oral fluid intake is more than their output.. etc. I'm just wondering when it is safe to take them off and what the parameters/what is within nursing scope of practice to do so. I've seen nurses stop fluids, but never get great answers as to why they decided to put them on saline lock. Also, what would warrant a nurse to put them back on the fluids after putting them on a saline-lock. I would love feedback. Thanks in advance.

[KelRN215, BSN, RN]

Probably every hospital does things differently and it depends on a lot of factors. Some surgeries we expect the kid to discharge on POD 1 or 2 so if their nausea was controlled overnight, we'd hep lock them on the morning following to PO challenge. If they weren't meeting their maintenance fluid goals, they went back on the IV. Usually we tried to keep them hep locked during the day to PO challenge them and hooked them up at night if they couldn't meet their fluid needs. For babies, they eat/drink all night so if they were feeding well overnight, they'd probably get hep locked in the morning. For other conditions, the patient shouldn't be hep locked regardless of their PO intake. Some chemotherapies and IV acyclovir require a certain amount of IV fluid for renal protection. Some cerebral vascular conditions require 1.5x IV fluid maintenance.