Positive test dose in a neonate with a caudally placed epidural catheter

Abstract

We present a case of a neonate with an epidural catheter placed via the caudal route after induction of general anaesthesia in whom the test doses of epinephrine-containing local anaesthetic was positive on two occasions. Remarkable tachycardia was noted after each of two separate injections through the catheter. Blood was never aspirated from the catheter and placement was without difficulty. After the catheter was removed, blood was noted at the tip.

Pharmacokinetics and efficacy of ropivacaine for continuous epidural infusion in neonates and infants

“…A transient elevation of the T‐wave amplitude has been suggested as a sign of accidental intravenous injection of local anesthetic and could indicate a toxic reaction (23–25). This has been disputed by others (26,27).…”

Neonatal T‐wave elevation from a positive epidural test dose

“…Heart rate increase and T‐wave changes have emerged as valuable parameters (1). Heart rate increase during test dosing in a neonate has been reported (2). We recently observed a pronounced T‐wave increase following test‐dose injection in a neonate.…”

“…In the study by Fisher et al (1), small children received higher volumes of test dose and thus higher doses of epinephrine per kg, which were commonly 1 μ g·kg −1 and higher in patients of <5 kg weight according to the graph in their publication. Because the dead space of the epidural catheter can be significant during test dosing in neonates, the test dose needs to be either flushed in (2) or the dead space needs to be accounted for when calculating the test‐dose volume. We chose a test‐dose volume of 1 ml.…”