Jonathan Shaw and the Epicutaneo-Cava catheter
Although today’s topic focuses on the work of Dr Jonathan C.L. Shaw, it is important to remember that successfully providing total parenteral nutrition (TPN : nutrition exclusively with an intravenous catheter) as the sole nutritional support for growth, development and metabolic maintenance, first in animals, then in a newborn and then in adults, has not been the result of overnight advances but rather the result of scientific, technological, philosophical and practical advances in basic science and clinical medicine by countless researchers and clinical scientists over several decades (1).
Jonathan Shaw was not the first to apply TPN to neonates. During the 1950s and until the late 1960s, TPN did not exist. Parenteral nutrition was partial, administered together with enteral nutrition (nutrition with a gastric tube). TPN was first applied in 1967 to Beagle dogs by Dudrick, Rhoads and Vars. Six dogs were fed by TPN for 72 to 255 days (2).
After that successful experiment, TPN was implemented on a newborn girl, with an intestinal obstruction, for whom enteral nutrition could not be used. Doctors inserted a PVC tube into the baby’s external jugular vein through a needle and tunneled the catheter (see picture) to prevent accidental removal. The TPN lasted 44 days. On day 45, a combination of parenteral and enteral nutrition started. (3)
TPN was then used in 30 adults who had chronic gastrointestinal diseases for periods of 10 to 200 days.This was in 1968.
Jonathan Shaw : who was he ? What is his contribution to neonatal medicine ?
Jonathan C.L.Shaw was a neonatologist working in the NICU at University College Hospital in London. He worked there for 30 years before retiring in 1999. What was his role in 1973, year of publication of his article which later led to the Epicutaneo-Cava catheter ?
- Firstly, based on the work mentioned above, as well as the studies of the nutritionist Elsie Widdowson, Jonathan tried to give the newborn babies the same type of nutrition that they would have received if they had remained in their mother’s uterus, but he did it intravenously, overcoming all the difficulties, for example obtaining adequate calcium (so important for the development of bones and teeth), which was very difficult at the time, and that was a huge conceptual leap. (4)
- Jonathan Shaw’s second merit was to use a material that is much better tolerated by premature and newborn babies than PVC: silicone. (5)
In 1973, parenteral nutrition consisted of a solution of fat-free hyperosmolar glucose, amino acids, minerals and vitamins administered directly into the right atrium or large central vein.
Contrary to Dudrick who used the external jugular vein of the baby girl (with intestinal obstruction), which according to Shaw could interfere with the inspired oxygen concentration, he chose other veins : scalp veins, saphenous vein (in the leg), medium cubital vein (in the arm), veins in the back of the hand.
The catheter was made of non-radio-opaque silicone, most commonly 0.63 mm external diameter, or 0.92 mm for older children. The venous puncture was done with a 19G scalp vein set (winged needle : see drawing below) for the smaller catheter and 16G for the larger catheter, after cutting the extension tube of the scalp vein set and the catheter was introduced with forceps. The hospital bought rolls of silicone tube from Dow Corning, the tube was cut into 50 cm lengths, double-packed and autoclaved.
To prevent glove dust from adhering to the surface of the catheter, which could cause thrombophlebitis, the gloves were rinsed 3 times with distilled water. To control the position of the catheter, Shaw recommended that a radiographic check should always be made after filling the catheter with contrast material. The winged needle used as an introducer was removed and a 25G scalp vein set was used to connect the catheter to the infusion set. The needle protector of the 25G scalp vein set was first mounted on the proximal end of the catheter, the catheter was connected to the butterfly needle and the protective tube covered the assembly and served as an anti-puncture device. A dressing was applied to the cutaneous exit site of the catheter.
The filter and the bottle containing the intravenous solution were sent daily to the laboratory for culture. The silicone catheter was used only for parenteral nutrition. If there was a need to infuse something else, another device was used. If the infusion lasted several weeks, Shaw recommended changing the catheter every 20 / 30 days. The main complication was infection not only of the catheter but also of the infused solution.
In 1973 when he published his article, Shaw recognised that TPN was not ready for widespread use, that it should only be implemented by well-equipped units with many well-trained staff, but he already foresaw that TPN would gain an important place in the routine management of sick underweight children. (5)
Creation of Vygon Epicutaneo-Cava catheter
J. Shaw’s article led Vygon to create the Epicutaneo-cava catheter in 1976, code 2184.06 (see drawing). The catheter was made of non-radio-opaque silicone, 30 cm long with an external diameter of 0.6 mm which was inserted with a 19G winged needle (the current needle). The connection to the infusion set was made with a 27G scalp vein set from which the bevel of the needle had been removed. This product has been sold until 2017, but in small quantities in the recent years.
The product we know today, code 2184.00, appeared in the early 80's.
It has been sold in millions of units all over the world, although today Premicath sells much more than the Epicutaneo-Cava catheter (ECC). ECC is still a key product in the Vygon range of neonatal PICCs. Users appreciate its flexible, non-traumatizing material; the silicone catheter floats in the bloodstream limiting damage to the vascular endothelium and, taking into account the extremely fragile tissues of premature/neonatal infants, limits the risk of erosion of the venous wall, of its perforation, the risk of pericardial effusion and of cardiac tamponade.
Jonathan Shaw’s work has made an essential contribution to the development of total parenteral nutrition in neonates and to the development of peripherally inserted neonatal central venous catheters. This type of catheter, of catheterization practiced in neonates :
- reduces the risks associated with puncturing the neck or chest veins (pneumothorax, haemothorax, injury to a nerve of the brachial plexus, etc.)
- allow a much longer duration of intravenous therapy than an umbilical catheter
- While short catheters and scalp vein sets have a very short lifespan in neonates (30 to 50 / 60 hours) which implies :
. numerous repeated punctures that are very painful and traumatic for children. In this regard, it is known that repetitive harmful stimuli in the early stages of life have been associated with later impacts such as behavioural and emotional difficulties during childhood, the tendency to greater psychosis, intractable pain syndromes…
. a high risk of infiltration and extravasation (infusing outside of the vein)
. frequent interruptions of the intravenous therapy with risks of hypoglycaemia, dehydration,
. risks of phlebitis and erythema (irritation, inflammation of the vein)
. the exhaustion of the peripheral veins
. the risk of arterial puncture
. not being able to infuse hyperosmolar solutions and medicines whose pH is less than 5 or more than 9, because the small peripheral veins do not tolerate these aggressive elements .
With an Epicutaneo-Cava type neonatal PICC, with which the infusion is made in the superior or inferior vena cava (featuring a much bigger diameter, and with higher flow rates, diluting rapidly the aggressive fluids), there is no limitation to the type of fluid (medicine or solution) which is administered to the child, all the problems (mentioned above) which occur with short catheters or scalp vein sets are avoided. All this clearly improves the clinical outcome and contributes to the success of the therapy applied to the child.
We owe all this to Dr Jonathan Shaw and his legacy, 50 years after his invention, remains still present in neonatal intensive care units.
Gesuino Mureddu
Pole of Medical & Scientific Expertise
Sources:
(1) History of Parenteral Nutrition — SJ Dudrick — Journal of the American College of Nutrition — Vol. 28–2009
(2) Growth of Puppies Receiving all Nutritional Requirements by Vein — SJ Dudrick et al. — Fortschr Parenteral Ernährung, 2, 1967
(3) Growth and Development of an Infant receiving All Nutrients Exclusively by vein — DW Wilmore, SJ Dudrick — JAMA, Vol. 203, 1968
(4) Origins of Neonatal Intensive Care in the UK — Seminar held in London in 1999. Transcript edited by DA Christie and EM Tansey
(5) Parenteral Nutrition in the Management of Sick Low Birthweight Infants — JCL Shaw — Pediatric Clinics of North America — Vol. 20, 2, 1973
