Dispatch Life Support (Pre-Arrival Instructions)
What dispatch life support is
Dispatch Life Support is the set of medically approved instructions the EMD delivers by telephone before responders arrive. It has two families: Post-Dispatch Instructions, given as a routine part of the call, and Pre-Arrival Instructions, given when a specific protocol calls for them and when the situation is time-critical - CPR, choking relief, bleeding control, and childbirth are the classic examples.
Delivering instructions that work
Good pre-arrival instruction is a performance skill. Get the caller's agreement to help, then give one instruction at a time, in plain language, and confirm each step before moving to the next. Tell the caller to put the phone on speaker so both hands are free. Stay on the line. Do not improvise, do not add steps the protocol does not contain, and do not skip steps because the caller says he already knows what to do. If a second person is present, direct that person and keep the caller on the line as your coach.
Traps
Typical exam traps: beginning CPR instructions before confirming the patient is unresponsive and not breathing effectively; skipping the question of whether anyone on scene knows CPR; delivering a rapid paragraph of instructions and assuming it was followed; abandoning the protocol because the caller resists (redirect rather than argue); and failing to hand off cleanly - telling the caller to hang up while compressions are in progress. Also watch for instructions given out of sequence, and for instructions that exceed the EMD's scope, such as advising medication doses.
Rule of thumb: if the patient is not breathing effectively and is unresponsive, compressions start now - pre-arrival instruction does not wait for the full interrogation to finish.
Worked example: a caller reports an adult who collapsed and is not breathing. The EMD confirms unresponsiveness and ineffective breathing, selects the highest applicable determinant, dispatches, then moves immediately into compression instructions - one step at a time, speakerphone on, caller kept on the line until responders take over.