Five Ps of critical limb ischemia

Five Ps of critical limb ischemia (acute limb ischemia)

1. Pain
2. Pallor
3. Paraesthesia
4. Paralysis
5. Pulselessness

Some authors add one more – Poikilothermia and make it Six Ps of critical limb ischemia.
Poikilothermia means that the limb has lost its temperature control mechanism. Hence it assumes room temperature, usually colder than rest of the body.

Rutherford classification for acute limb ischemia

Rutherford classification has been used in the setting of acute limb ischemia [1]. In category I, the limb is viable, there are no neurological signs and arterial sounds are audible on Doppler evaluation. Category II is viability threatened, but reversible ischemia. This category is subdivided into IIa and IIb. IIa is marginally threatened, with sensory loss, absent arterial sound on Doppler, but audible venous sound. IIb is immediately threatened, with some degree of muscle weakness, arterial sounds inaudible on Doppler, venous sounds audible. Category III is irreversible ischemia with paralysis, contracture and inaudible arterial and venous sounds on Doppler.

Thromboembolectomy with a Fogarty catheter

Thromboembolectomy with a Fogarty catheter is the age old treatment for acute limb ischemia. Usual protocol is surgical dissection and exposure of the common femoral artery, superficial femoral artery or brachial arteries depending on the case. Supplementary distal access may be used when needed [2]. Though the procedure is meant for Rutherford category I and II, occasionally it may be indicated in category III. This is to relieve ischemia and/or restore blood flow to collaterals. Objective in that case is for achieving a more distal amputation, osteoarticular preservation and better rehabilitation. Among the 105 patients evaluated in the study, thromboembolectomy with a Fogarty catheter was performed in 73.3% of cases. Arterial reocclusion was more frequent in thrombosis cases compared to embolic cases. Major amputations were less frequent among Rutherford Class I patients, as expected.

References

1. Rutherford RB. Clinical staging of acute limb ischemia as the basis for choice of revascularization method: when and how to intervene. Semin Vasc Surg. 2009 Mar;22(1):5-9.
2. Teodoro C, Bertanha M, Girard FPCM, Sobreira ML, Yoshida RA, Moura R, Jaldin RG, Yoshida WB. Results of treatment of acute occlusions of limb arteries at a university hospital – retrospective study. J Vasc Bras. 2020 Nov 16;19:e20200031.