In May/June 2015, the “Journal of Infusion Nursing” dedicated an article to short catheters that states:
“The insertion of short peripheral catheters, the most common invasive procedure in hospitals around the world, is associated with a variety of complications and an unacceptable failure rate of between 35% and 50%, even in the best hands.
This failure has an adverse effect on patients, professionals and the health system. Although progress has been made in this area, analysis of the mechanisms that demonstrate a persistently high failure rate with short peripheral catheters shows that there are opportunities for improvement.”
But why do short catheters have such poor results ?
In this technique called “over-the-needle technique”, the four main steps are as follows:
A. Puncture: blood reflux into the hub of the catheter
B. Advancing the catheter over the needle (the needle must remain in the same position as in step A)
C. Removing the needle
D. Connecting the infusion system (containing the therapy or solution to be infused)
During step B or C, the vein may be lost. If the catheter has not been pushed far enough or has been pushed through (transfixation), the catheter tip is placed in a lower or lateral position to the vein.
The catheter should be removed and another attempt should be made in another site, another vein or even the other arm if the practitioner feels this is appropriate.
Nevertheless in some cases, due to fear of losing the access on the first attempt, the same catheter is used to continue to search for the vessel lumen, resulting in movements of the catheter, removal, re-entry of the tissue at a larger or smaller angle, changes in direction and so on.
The insertion becomes a much more invasive process. Injury to the vein itself and adjacent tissue increases the risk of early complications (haematoma, extravasation) and consequently the risk of malfunction and/or early catheter removal.
Standard short peripheral catheters are made of a rigid plastic and their biocompatibility is limited and so exceeding or even reaching three days of use is difficult. The materials they are made of, such as Teflon and polyethylene, make insertion easier because they are rigid, but they can cause (mechanical) phlebitis.
On the other hand, drugs weaken them over time due to reduced chemical resistance.
The calibre of the veins
As it is a catheter of reduced length and it is inserted in the forearm, its tip will be located in a small-calibre vein. A peripheral vein has a very reduced flow compared to a deep vein such as the basilic or cephalic vein (250 ml/min). This is an example of the ulnar vein in its distal section:
Due to it having a limited flow, the rate at which drugs are infused is inadequate and the vein may not be able to cope. If the catheter takes up more than a third of the vein’s lumen, it becomes even more difficult to perform because it is exposed to a higher risk of injury and phlebitis.
The type of drugs
The guidelines on vascular accesses say that through a peripheral route only therapies with the following characteristics should be infused:
– A pH between 5 and 9
– An osmolarity below 600 mOsm/L
It is vital to know these 2 characteristics in the medication to be administered before channelling the route to the patient in order to avoid deterioration of the venous capital due to vesicant drugs (chemical phlebitis).
The rigidity, the low biocompatibility of its material, as well as the insertion technique, mean that the short peripheral catheter can cause problems over time. For this reason, its use must be rationalised, knowing the pros and cons to ensure correct handling. As in all care, training plays a fundamental role.
The key aspects are:
– Using this type of route for therapies which do not exceed six days
– Do not infuse vesicant medication: osmolarity must be <600mOsm/L and pH between 5 and 9
– Make an assessment of the patient’s venous capital: use only if there are three or more suitable puncture sites
– Establish strict protocols for route placement and maintenance to standardise practice and minimise complications
– Consider whether the patient is going to be admitted or going home
– Assess other options in the event of prolonged therapy.
– Removal of Peripheral Intravenous Catheters Due to Catheter Failures Among Adult Patients Murayama, Ryoko PhD, RN, RMW; Uchida, Miho MSI, RN; Oe, Makoto PhD, RN; Takahashi, Toshiaki MHS, RN; Oya, Maiko RN, RMW; Komiyama, Chieko RN; Sanada, Hiromi PhD, RN, WOCN Journal of Infusion Nursing: July/August 2017 – Volume 40 – Issue 4 – pp. 224-231
– Short Peripheral Intravenous Catheters and Infections Hadaway, Lynn MEd, RN, BC, CRNI® Journal of Infusion Nursing: July/August 2012 – Volume 35 – Issue 4 – pp. 230-240 doi: 10.1097/NAN.0b013e31825af099
– Phlebitis Signs and Symptoms With Peripheral Intravenous Catheters: Incidence and Correlation Study Mihala, Gabor, MEng, GCert (Biostat); Ray-Barruel, Gillian, PhD, RN; Chopra, Vineet, MD, MSc; Webster, Joan, BA, RN; Wallis, Marianne, PhD, RN, FACN; Marsh, Nicole, MAdvPrac, BN, RN; McGrail, Matthew, PhD, GradDip (IT), BSc (Hons); Rickard, Claire M, PhD, RN Journal of Infusion Nursing: July/August 2018 – Volume 41 – Issue 4 – pp. 260-263
– Flebitis zero http://flebitiszero.com/site/wp-content/uploads/2014/09/1.Definición-Flebitis.pdf Hit That Vein
– Tips and Techniques for Inserting an IV Cannula https://www.ausmed.com/articles/how-to-place-an-iv/