Tobramycin blood levels from an indwelling right atrial catheter

Indwelling right atrial catheters provide continuous access to the venous circulation for the purpose of long-term alimentation and blood collection. Two types of central venous systems are the Broviac and Hickman catheters. In general, the Hickman is more versatile, allowing easy blood sample collection, in addition to continuous intravenous fluid and drug administration. Two cases are presented where apparent erroneous tobramycin blood samples were collected through one of these catheter systems. One case compares Hickman tobramycin blood levels with standard peripheral venicollection. Possible ramifications and solutions to the problem are discussed.