An unusual course of a long line into a thoraco-epigastric vein in a preterm neonate

A male infant (second twin) born at 30 weeks’ gestation, weighing 1,390g required continuous positive airway pressure (CPAP) after admission. On day 1, a long line was inserted into the right arm and fixed at 10cm for parenteral nutrition. Ideally, the long line would have passed through the axillary vein to the subclavian vein and into the superior vena cava, however, a chest X-ray showed the line’s route as through the basilic vein to the axillary vein, followed by a turn into the lateral thoracic vein extending into the thoraco-epigastric vein (FIGURES 1 and 2). This line was removed and replaced by another long line in the leg.

FIGURE 1 A chest X-ray showing the unusual course of a long line from the basilic vein into the axillary vein and then into the thoraco-epigastric vein (arrow).

FIGURE 1 A schematic diagram showing the venous anatomy of the upper limbs.

Long lines, while used commonly, are known to incur risks. Guidelines¹ advise confirming the position by X-ray (with or without contrast) due to the significant morbidity associated with malposition. A misplaced long line could lead to complications such as cardiac tamponade if the tip is located in the heart; liver injury if located within the liver; neurological complications if located in the lumbar vein^2,3 and extravasation injury. It is therefore recommended that the tip be positioned in a large vein outside the cardiac shadow.⁴ This is particularly true when using parenteral nutrition as the high osmolarity of the solution can cause vascular wall damage and injury to the surrounding tissue.⁴

The thoraco-epigastric vein is a small vein that runs super-ficially along the lateral chest wall. Line insertion into this site is extremely rare and not an ideal position for infusing parenteral nutrition. The closest scenario reported describes an accidental cannulation of the epigastric vein5 causing hypoglycaemia and extravasation-related acute abdomen requiring surgical intervention. It is, therefore, vital to check the long line position before its use.