Medical apparatus are disclosed for optoacoustic monitoring of an indwelling unit of the apparatus, where the indwelling unit includes one or more optical components capable of directing pulsed light into an overlying tissue. The apparatus also include one or more acoustic components in contact with an exterior surface of the tissue to detect induced pressure waves producing an acoustic output analyzed with an optoacoustic unit to monitor and confirm proper placement of the indwelling unit. Methods for using the apparatus are also disclosed.
