cardiac chest pain in past 2hrs
BP < 100mmHg or HR < 50 or HR > 120 or resp. distress or RR > 30 unless chronic and stable
temporary pacing wire
GCS falling > 2 points in 24hrs
suspected SAH, ruptured AAA, or meningococcal septicaemia
major trauma or suspected spinal cord injury
bleeding in 3rd trimester or labour