SpaceLabs AM66 Fetal Monitor

The AM66 is an antepartum (pre-labor) fetal monitor for measuring and recording maternal and fetal activity. Data is displayed on the front panel, recorded on a strip chart recorder, and if the transmission option is installed, can be transmitted via telephone modem to a remote data receiver. The transmission option is installed on all Medical Specialties-owned units.

Uterine activity and fetal heart rate is monitored externally using a ultrasound transducer strapped to the abdomen of the patient. This transducer sends sound waves into the maternal abdomen and detects echoes coming from moving objects within. The monitor analyzes these echoes, picking out indications of fetal heart motion, and uses the rhythm of the motions to compute heart rate. At the same time, the tocotransducer detects uterine activity by sensing changes in tension on the abdomen.

The AM66 also has the capability to monitor twins. This requires the use of a second ultrasound (green dot) transducer. Use two green dot ultrasound transducers to measure twin’s fetal heartrates, one plugging into the rear and one into the front of the unit. The one in the rear prints out as maternal heartrate, with front indicated as fetal on printout. This can be changed to have both print out as fetal by reprogramming during the calibration procedure. The red dot tocotransducer is used to measure uterine contractions.

The data produced can be transmitted over telephone line to either a second AM66 unit at the remote receiving location, or by using a DR100 data receiver. 80 minutes of data can be stored in memory for this transmission (40 minutes when monitoring twins).

Suggested Substitutions: Hewlett Packard 8040A, SpaceLabs DT100 Data Transmitter (below)

SpaceLabs DT100 Data Transmitter (UXDT100B) and
DR100 Data Receiver (UXDR100)

The DT100 Data Transmitter performs the same function as the AM66, collecting, storing, and transmitting fetal heart rate and uterine activity. However, it provides no printout of activity, and must be used in conjunction with the DR100 Data Receiver, which receives all the data from the DT100 at a remote site and plots the data on a thermal strip chart recorder. The DR100 can also receive data transmitted by the AM66; conversely, the AM66 can be used to receive data transmitted by the DT100. Receivers can accumulate data from more than one transmitting unit. The DT100 can digitize and store up to 120 minutes of Uterine Activity data for transmission.  The manufacture of both the DT100 and the DR100 has been discontinued by  SpaceLabs, but the company still offers service support for the discontinued models.