SOFA score

A limitation of the APACHE and SAPS scoring systems is that they were designed and validated on data obtained during the first 24h of intensive care admission. Various systems have been developed to enable daily scoring (e.g. Sequential Organ Failure Assessment (SOFA), Riyadh Intensive Care Program (RIP) score, Multiple Organ Dysfunction Score (MODS), etc.) to allow a better assessment of change in the patient’s condition.

As the physiological and biochemical status of the patient is determined in part by the disease severity, but also by the degree of medical intervention, these sequential scoring systems incorporate the use of various therapies and procedures.

The SOFA system was initially designed to improve patient characterization for multicentre drug trials in sepsis (SOFA initially stood for ‘Sepsis organ failure assessment’), but has subsequently been applied to intensive care patients in general, with ‘Sequential’ being substituted for ‘Sepsis’.

Although it has not been validated in the sense that a point score denoting severity of dysfunction in one organ system does not translate directly to an equivalent severity in another organ, it has been used successfully to prognosticate and to follow changes in patient status throughout their intensive care stay (see table opposite).

 SOFA score

Conversion factors

• PaO2:FIO2 to kPa: divide by 7.5.

• Creatinine to μmol/L: multiply by 88.

• Bilirubin to μmol/L: multiply by 17.1.