Optimising circulation

We recommend aggressive and timely stabilisation of cardiac pre-load throughout the surgical procedure, as this appears beneficial to the patient. 1B

In cases of uncontrolled bleeding we suggest lower thresholds for cardiac pre-load and/or permissive hypotension may be considered. 2C

We recommend the avoidance of hypervolaemia secondary to crystalloids or colloids to a level exceeding the interstitial space in steady state, and beyond an optimal cardiac pre-load. 1B

We recommend against the use of central venous pressure (CVP) and pulmonary artery occlusion pressure as the only variables to guide fluid therapy and optimisation of pre-load during severe bleeding. Dynamic assessment of fluid responsiveness and non-invasive measurement of cardiac output should be considered instead. 1B

We suggest the replacement of extracellular fluid losses with isotonic crystalloids in a timely and protocol-based manner. 2C

Compared with crystalloids, haemodynamic stabilisation with iso-oncotic colloids, such as human albumin and hydroxyethyl starch, causes less tissue oedema. C

Infusion of colloids in patients with severe bleeding can aggravate dilutional coagulopathy by additional effects on fibrin polymerisation and platelet aggregation. C

We suggest the use of balanced solutions for crystalloids and as a basic solute for iso-oncotic preparations. C

Transfusion triggers
We recommend a target haemoglobin concentration of 7 to 9 gdl-1 during active bleeding. 1C

Continuous haemoglobin monitoring can be used as a trend monitor. C

Oxygen fraction
We recommend that the inspiratory oxygen fraction should be high enough to prevent arterial hypoxaemia in bleeding patients, while avoiding excessive hyperoxia (PaO2 >26.7 kPa [200 mmHg]). 1C

Monitoring tissue perfusion
We recommend repeated measurements of a combination of haematocrit (Hct)/haemoglobin, serum lactate, and base deficit to monitor tissue perfusion, tissue oxygenation and the dynamics of blood loss during acute bleeding. These parameters can be extended by measurement of cardiac output, dynamic parameters of volume status [e.g. stroke volume variation (SVV), pulse pressure variation (PPV)], CO2 gap and central venous oxygen saturation. 1C

Normovolaemic haemodilution
We suggest the use of acute normovolaemic haemodilution (ANH) in selected settings. 2C

We recommend against ANH in combination with controlled hypotension. 1B

In patients with pre-existing or acquired coagulopathy we suggest that the use of ANH is considered carefully. 2C