{"id":3695,"date":"2015-06-22T23:04:35","date_gmt":"2015-06-22T23:04:35","guid":{"rendered":"http:\/\/opentextbc.ca\/clinicalskills\/?post_type=chapter&p=3695"},"modified":"2021-06-09T16:48:22","modified_gmt":"2021-06-09T16:48:22","slug":"3-3-care-of-iv-tubing-administration-sets","status":"publish","type":"chapter","link":"https:\/\/opentextbc.ca\/clinicalskills\/chapter\/3-3-care-of-iv-tubing-administration-sets\/","title":{"raw":"8.5 Flushing a Saline Lock and Converting a Saline Lock to a Continuous IV Infusion","rendered":"8.5 Flushing a Saline Lock and Converting a Saline Lock to a Continuous IV Infusion"},"content":{"raw":"A saline lock (SL)<\/strong>, also known as a heparin lock, is a peripheral intravenous cannula connected to extension tubing with a positive pressure cap (see Figure 8.7). This device allows easy access to the peripheral vein for intermittent IV fluids or medications (Perry, et al., 2014). The saline lock is \"flushed\" or filled with normal saline to prevent clotting when not in use. To use an SL, the cannula is flushed with 3 to 5 ml of normal saline to assess patency. After the saline lock is used, the cannula is flushed again with 3 to 5 ml of normal saline or heparin to \"lock\" the saline in the cannula in order to keep it patent. Once the saline lock is inserted, it can be left in a vein for up to 72 hours or as per agency policy. Saline locks are usually inserted in the arm or hand. If a saline lock is removed, the extension tubing and positive pressure cap are also changed (Vancouver Coastal Health, 2012).\r\n\r\n[caption id=\"attachment_6155\" align=\"aligncenter\" width=\"300\"]\"Saline<\/a> Figure 8.7 Saline lock with positive pressure cap (Max Plus)[\/caption]\r\n\r\nA saline lock can be used for continuous and intermittent short-term IV therapy. Flushing is performed:\r\n