Radioisotope blood volume measurement in uncontrolled retroperitoneal haemorrhage induced by a transfemoral iliac artery puncture

Standard-of-care, large volume crystalloid infusion, in the setting of unco ntrolled bleeding, has been challenged and it is not known if fluid resusci tation increases retroperitoneal hemorrhage. We developed an experimental m odel of retroperitoneal haemorrhage to correlate haemodynamic and metabolic alterations with the blood Volume loss. Anaesthetised, spontaneously breat hing dogs (17.1 +/- 0.56 kg) were randomised to unilateral (UL, n = 11) or bilateral (BL, n = 11) iliac artery puncture, using a metallic device intro duced through the femoral arteries and followed for 120 min. Initial and fi nal blood volumes were determined using radioactive tracers, (TC)-T-99m and Cr-51, respectively. UL was associated with a stable arterial pressure and a moderate decrease in cardiac output and oxygen delivery. BL induced an a brupt and sustained decrease in mean arterial pressure, from 131.9 +/- 5.9 to 88.6 +/- 10.8 mmHg, and a much greater reduction in cardiac output, oxyg en delivery and consumption than UL throughout the experiment. Total retrop eritoneal blood loss after BL was 36.8 +/- 3.2 ml/kg, while after UL was 25 .1 +/- 3.4 ml/kg (P = 0.0262). We conclude that a transfemoral bilateral il iac artery puncture produces a clinically relevant model of uncontrolled re troperitoneal haemorrhage, with hypotension and low flow state, while a uni lateral iliac artery lesion causes a compensated shock state. (C) 2001 Else vier Science Ltd. All rights reserved.