This code system http://hl7.org/fhir/deviceassociation-status defines the following codes:

CodeDisplayDefinition
implanted ImplantedThe device is implanted in the patient.
explanted ExplantedThe device is no longer implanted in the patient. Note that this is not the value to be used for devices that have never been implanted. In those cases, no value or a specific value can be used.
entered-in-error Entered in ErrorThe association was entered in error and therefore nullified.
attached AttachedThe device is attached to the patient but not implanted in the patient.
unknown UnknownThe association status of the device has not been determined.
<status value="active"/><experimental value="false"/><publisher value="HL7 International"/><description value="DeviceAssociation Status Codes"/><jurisdiction><coding><system value="http://unstats.un.org/unsd/methods/m49/m49.htm"/><code value="001"/><display value="World"/></coding></jurisdiction><caseSensitive value="true"/><valueSet value="http://hl7.org/fhir/ValueSet/deviceassociation-status"/><content value="complete"/><concept><code value="implanted"/><display value="Implanted"/><definition value="The device is implanted in the patient."/></concept><concept><code value="explanted"/><display value="Explanted"/><definition value="The device is no longer implanted in the patient. Note that this is not the value to be used for devices that have never been implanted. In those cases, no value or a specific value can be used."/></concept><concept><code value="entered-in-error"/><display value="Entered in Error"/><definition value="The association was entered in error and therefore nullified."/></concept><concept><code value="attached"/><display value="Attached"/><definition value="The device is attached to the patient but not implanted in the patient."/></concept><concept><code value="unknown"/><display value="Unknown"/><definition value="The association status of the device has not been determined."/></concept></CodeSystem>