title: Is transcutaneous oxygen and carbon dioxide monitoring indispensable in short- and long-term therapeutic management of non-reconstructable lower critical limb ischemia?
abstract: OBJECTIVE
  The aim of this study was to evaluate the capacity of transcutaneous partial pressure of O(2) (TCpO(2)) and CO(2) (TCpCO(2)) to predict clinical response to pharmacological treatment in short- and long-term follow-up of unreconstructable critical limb ischemia (CLI) treated with prostanoids; to suggest a diagnostic and therapeutic algorithm able to define the possibility of prostanoid therapy in unreconstructable CLI at high risk of limb loss.
  
  
  METHODS
  Twenty-six consecutive patients with CLI (21 with distal trophic lesions, 31 symptomatic limbs) considered unreconstructable after peripheral angiography and with a history of type 2 diabetes mellitus underwent daily parenteral Iloprost treatment for 2-3 weeks.
  
  
  RESULTS
  Transcutaneous gas-analytic monitoring (TGM) in non-reconstructable CLI treated with Iloprost divided patients into 2 groups: early responders (ER) with increased TcpO(2) and normalization of TcpCO2, and non responders (NR) with unchanged TcpO(2) and TcpCO(2) parameters. In the NR who underwent a second cycle of Iloprost within a few months of the first, TGM further divided the patients into another subgroup of late responders (LR) with TcpO(2) and TcpCO(2) similar to the ER group and a subgroup of NR, who, after pharmacological treatment failure, should undergo eventual surgical re-timing and/or spinal cord stimulation in a final attempt to save the limb.
  
  
  CONCLUSIONS
  In the short-term follow-up of CLI, a marked reduction in supine/dependent TcpO(2) and a marked increase in supine TcpCO(2) at the symptomatic forefoot proved to be significant predictors of major amputation risk. In the long-term follow-up period, TGM showed that, in ER and in LR, the favourable effect of pharmacological therapy observed in the first 6 months will disappear over the next 6 months, suggesting an algorithm of 2- to 3-week cycles of prostanoid therapy repeated every year. In NR treated with surgical and/or alternative therapies who did not undergo major amputations, prolonged instrumental TGM will provide a constant evaluation of metabolic parameters, thus providing the possibility to save the limb with additional pharmacological therapy.
authors.affiliation: Angiology Unit, Cardio-Thoracic Department Azienda Ospedaliero-Universitaria Pisana, Pisa, Italy. e.melillo@ao-pisa.toscana.it
authors.forename: E
authors.initials: E
authors.lastname: Melillo
authors.forename: M
authors.initials: M
authors.lastname: Nuti
authors.forename: R
authors.initials: R
authors.lastname: Pedrinelli
authors.forename: F
authors.initials: F
authors.lastname: Buttitta
authors.forename: A
authors.initials: A
authors.lastname: Balbarini
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001785:Blood Gas Monitoring, Transcutaneous; D016638:Critical Illness; D005260:Female; D006801:Humans; D016285:Iloprost / Q000627:therapeutic use*; D007511:Ischemia / Q000097:blood* / Q000188:drug therapy*; D007866:Leg / Q000098:blood supply*; D008297:Male; D008875:Middle Aged; D013997:Time Factors; D014665:Vasodilator Agents / Q000627:therapeutic use*
chemical_list: D014665:Vasodilator Agents; D016285:Iloprost