Asynchronous Communication - unidirectional information flow (i.e., text, e-mail), sometimes known as store and forward, refers to telemedicine that is delivered at a later time from when the patient or another healthcare provider requests it. This could be text-based interactions, a specialist reviewing labs or records at a later time, or a patient conducting an online assessment for medications.

Bandwidth - the amount of information that may move through a network at any point in time. Think of it like a door or a turnstile: only one or two people can fit through at a time. Similarly, packets of digital information flow through wires and those wires, or their connections, are limited in size and thus only allow a certain amount of information to pass through them at a time. Thus, packets must “get-in-line” such that some arrive to their destination before others. If the network is not “point-to-point” and serves multiple users, then these users must share the bandwidth. Some information on the network can be considered “higher priority” than other information. Quality of services protocols allow certain types of information or information from a particular source/user to move more freely (i.e. may go to the “head of the line”) than other information.

Consultant/Expert- the clinician who receives the consult from the local caregiver. This may be a designated consultant in a formal system, or a validated and/or trusted expert provider chosen by the local caregiver

Distant Site- a distant site is the location the telemedicine provider is in at the time of remote patient service. Sometimes this is referred to as the consulting site.

Extended consultation- emergent consultation is for patients with critical illness or injury. This concept reflects clinical engagement more than communication modality. This refers to a consultant/expert who remains engaged with the care of a local patient or local patients over time by monitoring physiologic vital signs, audio channel(s), video feed(s), or combinations of these technologies.

Latency - the amount of time it takes information to travel from origination to destination. Most of the time, digital information travels quickly, even across hundreds of miles of distance. Still, using satellite communication to move from one side of the globe to the other, or from the moon to the earth, delays receipt of information. Information may also be slowed if it must pass through filters, firewalls, or scanning software.

Local Caregiver- the person (not necessarily someone with medical training) who is taking care of a patient and who initiates teleconsultation.

Originating Site- the originating site is the location the telemedicine patient is in at the time of remote patient service.

Remote Patient Monitoring- remote patient monitoring refers to technology and programs that help track patient health data at a distant site outside of the hospital or clinic and send that data to care providers in real time. This technology could be in the form of connected healthcare devices like a smartwatch or heart monitor, health monitoring and wellness apps, or connected home devices. Remote monitoring patient data can include vital signs, weight, blood pressure, blood sugar, and other inputs like mental health data or symptoms.

Routine consultations are those that do not require immediate assistance. Routine consultations may take many hours to receive a response from a specialist (4-24 hours; median response time is approximately 4 hours).

Synchronous Communication- bidirectional information flow (i.e. voice, video, both). Synchronous telemedicine refers to telemedicine that is performed in real-time via video or phone consult. In practice, this looks like an urgent care provider assessing symptoms of a sore throat and fever, a psychiatrist managing a patient’s medication, or a primary care provider conducting a follow-up visit with a patient.

Telemedicine- remote evaluation, diagnosis, treatment, and/or consultation using telecommunications technologies. Telemedicine is a subset of telehealth referring to the specific delivery of clinical healthcare services through telecommunications platforms. Examples of telemedicine could be video consults, phone consults, or patient-provider communication through text messages or a patient portal.

Teleconsultation – or “eConsult” is a caregiver to remote expert discussion about a patient’s diagnosis, diagnostic plan, treatment, or management plan using telecommunications technology such as a call, text, video consult, etc.

Urgent non-critical care specialty consultations are those in with remote consultants need to speak with a specialist in order to best manage a patient within hours. This could be a patient related need (i.e. the patient may worsen in the next several hours) or mission specific need (i.e. there is a short communications window or there is a mission essential decision to make like “does this casualty need to get on the evacuation platform that is leaving in the next hour or can he/she continue mission until the next available evacuation time”).

VTC – video teleconferencing is the ability to share audio and video signal between two locations to conduct real-time communication. This includes point-to-point (one location communicates to only one other location at a time) and multi-point (multiple locations communication with multiple other locations simultaneously).