This code system http://hl7.org/fhir/ex-diagnosisrelatedgroup defines the following codes:

CodeDisplayDefinition
100Normal Vaginal DeliveryNormal Vaginal Delivery.
101Appendectomy - uncomplicatedAppendectomy without rupture or other complications.
300Tooth abcessEmergency department treatment of a tooth abcess.
400Head trauma - concussionHead trauma - concussion.