Final answer:
The vital signs of an unstable patient awaiting transportation should be checked approximately every 5 minutes to allow for immediate response to any changes in the patient's condition.
Step-by-step explanation:
The vital signs of an unstable patient awaiting transportation should be checked every 5 minutes. This frequent monitoring is crucial as it allows healthcare providers to track the patient's condition closely and to respond swiftly to any deteriorations in their state. If a patient is unstable, their condition can change rapidly, hence the need for more frequent vital signs assessments. In some protocols, even more frequent checks may be warranted depending on the patient's status and presenting complaint.