Six Ps of critical limb ischemia

Six Ps of critical limb ischemia (CLI)

Classical clinical presentation of acute limb ischemia has been described as Six Ps of critical limb ischemia (CLI): [1]

  1. Pale
  2. Painful
  3. Pulseless
  4. Paralyzed
  5. Paraesthetic
  6. Perishing cold (or poikilothermia [2]  – impaired regulation of body temperature. The limb usually becomes cool, in accordance with room temperature, which is usually colder than body temperature)

Pallor is due to lack of blood supply. Pain is due to limb ischemia. Pulses are absent as expected, due to the vascular occlusion. Paralysis is due to ischemia of motor nerves and muscles. Paranesthesia is due to involvement of the sensory nerves.

Critical limb ischemia has dual importance of being more severe disease process and association with cardiovascular disease risk. 30% may require major amputation, defined as amputation above the ankle. Half of them can die in a year, mostly due to cardiovascular disease [1]. Read more on MALE – Major Adverse Limb Events (includes major amputation, reintervention which could be surgical or repeat angioplasty).


  1. Bailey MA, Griffin KJ, Scott DJA. Clinical Assessment of Patients with Peripheral Arterial Disease. Seminars in Interventional Radiology. 2014;31(4):292-299.
  2. Creager MA, Kaufman JA, Conte MS. Acute Limb Ischemia. N Engl J Med 2012; 366:2198-2206.

Earlier post: Five Ps of critical limb ischemia