Several indices exist to assess cerebral perfusion after cardiac arrest (CA).

We aimed to investigate a new approach allowing absolute flow and microvascular resistance measurement based on selective arterial continuous thermodilution before and after CA resuscitation in an animal model.

In anaesthetised pigs, intravascular absolute cerebral blood flow (CBF) and coronary blood flow (ABF) with corresponding microvascular resistances were measured. CA was induced with 3 and 5minutes of no-flow time in group 1 and 2, respectively. CBF was obtained at baseline, at 15minutes (T15) and 30minutes (T30) after resuscitation. Thereafter, CBF in the contralateral cerebral artery and ABF were measured.

Thirteen pigs were included in this protocol: five in group 1 and eight in group 2. The protocol could not be completed in three pigs from group 2 due to haemodynamic instability. Compared to baseline, significantly lower CBF (0.040±0.03 vs. 0.026±0.02L/min; P=0.03) and significantly higher cerebral microvascular resistances (2014±1015 vs. 3202±1838 Woods Units; P=0.04) were observed at T30. ABF and resistances remained stable at baseline, as compared to T30 (0.122±0.05 vs. 0.143±0.06L/min; P=0.15 and 563±203 vs. 478±181 Woods Units; P=0.36, respectively) with similar haemodynamic parameters. The same trend was observed in both groups according to no-flow time (Figure 1).

ABF and CBF measurement after CA resuscitation is feasible with thermodilution technique, allowing accurate monitoring and measurements. This novel approach allows simultaneous measurements of flow and microvascular resistances. This animal model simplifies experimentations to evaluate cerebral perfusion and test therapies.