What is the SOFA score?
The Sequential Organ Failure Assessment is a tool used to monitor critically ill patients condition while they are in ICU to assess the severity of organ dysfunction or how quickly the organ is failing. It is originally called as “Sepsis related Organ Failure Assessment” score.
Although many different scoring systems have been created, the SOFA score is now the most used application in the real world.
It was developed by consensus.
The SOFA trusted score is a scoring system that helps doctors to evaluate how well the organs systems in the body are functioning. There are six distinct components,
Respiratory system, Cardiovascular, Hepatic, Renal, Coagulation and Neurological system.
Image 1
Respiratory system : The PaO2/FiO2 ratio is a measure of oxygenation efficiency in lungs. It compares the amount of oxygen in the blood(PaO2) to the concentration of oxygen being delivered to the lungs(FiO2). A lower PaO2/FiO2 indicates that there is impaired oxygenation and may be indication of Acute respiratory distress syndrome (ARDS) or other respiratory disorders.
Cardiovascular Assessment: Its evaluation focuses on patient’s hemodynamic status, particularly through the assessment of MAP mean arterial pressure.
Hepatic system : Assessing Bilirubin levels as a marker of liver function.
Coagulation system : Examining platelet counts.
Renal system : Evaluating creatinine and urine output.
Neurological system : Assessing the Glassgow coma scale(GCS) score.
Each organ system receives a scoring range from 0 (normal) to 4 (abnormal),
With minimum SOFA score of 0 and the maximum SOFA score of 24.
What are SOFA morbidity and mortality rates ?
In the context of SOFA score, morbidity refers to extent of organ dysfunction or failure experienced by the patient. The SOFA scores commonly used on ICU patients to assess the severity of ill sepsis patients and predicts outcome.
Image 2
The United States Department of Health and Human Services (HHS) notes that the higher the SOFA score, the higher the risk of death.
Image 3: The mortality rate estimation is based on highest SOFA score during patient’s ICU stay.
A medical professional calculates this score for every 24 hours for a patient right from admission until discharge. The patient with SOFA score of 2 may have high chance of survival, while the score greater than 11 indicates very low chance of survival.
SIRS and QSOFA comparison
Both SIRS and QSOFA share similarities in their goals about predicting illness, still they differ in their focus, components and application.
Image 4
The criteria for SIRS include abnormalities in vital signs, with presence of two or more SIRS criteria indicates presence of infection or other inflammatory conditions.
Where as Quick SOFA is simplified version of SOFA score that focus on identifying patients with suspected infection who are at high risk poor outcomes such as sepsis or septic shock.
What is Lactate enhanced qSOFA ?
(LqSOFA) is modified qSOFA score is superior to the other four rapid scoring tools in predicting in-hospital mortality rate of the sepsis patients and in need for ICU admission.
4 Tools :
SIRS (Systemic inflammatory response syndrome)
QSOFA (Quick SOFA)
LQSOFA (Quick SOFA with serum Lactate criteria)
MEWS (Modified early warning score)
Altered mental status GCS <15,
Respiratory Rate: ≥22 breaths per minute,
Systolic Blood pressure ≤100mmHg
Serum Lactate levels ≥2mmol/L
Lactate enhanced quick SOFA is similar to Quick SOFA , which aims to improve early identification of patients at risk by including Lactate levels. Elevated lactate levels with tissue hypoperfusion and cellular dysfunction are considered as a marker of severity in sepsis.
QSOFA is simpler and quicker to apply, suitable for rapid assessment while LqSOFA offers an additional layer of assessment by incorporating lactate levels.
Analysis by comparing QSOFA and Lactate +QSOFA with sepsis patients in ICULOS for Every 24hours
In this chart, Both QSOFA and LqSOFA sepsis patients who are in ICU where meets
Above 2 components (altered mental status, low blood pressure and elevated lactate levels are said positive with 25–40% higher mortality risks.
If fewer than the 2 components are present, the mortality prediction is lower ranging from 10–25%.
Organ function analysis by comparing SIRS conditions and Lactate enhanced QSOFA
Image 5: QSOFA score 1, which meets 1 criteria , indicates low organ functional ,
QSOFA score 2, which meets 2 or more than indicates multi Organ Failure.
SIRS criteria are broader and can be triggered by various conditions beyond sepsis, It focus on inflammatory responses.
LqSOFA focus on organ dysfunction and abnormalities. It is more specific to sepsis related complications.
Insights From image 5 Organ Analysis, LqSOFA has been shown more specific organ functionality and organ failure to get the more predictive morbidity value in each age group.
“Patients who meet 2 or more of the above criteria considered as positive modified LQSOFA score, indicating an increased risk of mortality.
Conclusion:
By documenting valuable SOFA scores over time, clinicians track changes in patients’ clinical status, monitor response to therapy and communicate to healthcare team. This strategy helps in patient’s outcome.