What are the most clinically supported scoring systems, such as Pulmonary Embolism Rule-out Criteria (PERC) and Systemic Inflammatory Response Syndrome (SIRS), used in the emergency department?

From the Guidelines

The most clinically supported scoring systems used in emergency departments include PERC (Pulmonary Embolism Rule-out Criteria) and Wells criteria for pulmonary embolism risk assessment, as well as other tools such as HEART, qSOFA, SIRS, CURB-65, and PSI/PORT for various conditions. These tools help clinicians make rapid, evidence-based decisions about patient care, diagnostic testing, and disposition. The PERC criteria, in particular, have been validated in multiple studies, including a prospective validation study 1 and a randomized non-inferiority management study, which suggested safe exclusion of PE in patients with low clinical probability who met all criteria of the PERC rule. Some key points to consider when using these scoring systems include:

• The PERC criteria comprise eight clinical variables significantly associated with an absence of PE, including age < 50 years, pulse < 100 beats per minute, and no unilateral leg swelling 1.
• The Wells criteria and revised Geneva score can be used to predict pretest probability of PE, and a normal high-sensitivity d-dimer level can be used to further risk-stratify patients at both low and intermediate risk for PE 1.
• The use of these scoring systems can help standardize risk assessment, improve resource utilization, and enhance patient outcomes through more consistent decision-making in time-sensitive emergency situations. It is essential to note that while these scoring systems are valuable, they should complement rather than replace clinical judgment, as they are designed to be quickly applied at the bedside with readily available clinical information. In addition to PERC and Wells criteria, other scoring systems such as HEART, qSOFA, SIRS, CURB-65, and PSI/PORT can be used to assess various conditions, including chest pain, sepsis, pneumonia, and necrotizing soft tissue infections. Overall, the use of these clinically supported scoring systems can help emergency department clinicians make informed decisions about patient care and improve outcomes.

From the Research

Clinically Supported Scoring Systems

The following scoring systems are used in the emergency department to diagnose and manage various conditions:

• Pulmonary Embolism Rule-out Criteria (PERC) 2, 3, 4: a clinical diagnostic rule designed to exclude pulmonary embolism without further testing
• Systemic Inflammatory Response Syndrome (SIRS) 5, 6: a scoring system used to identify patients with a suspected infection
• quick Sequential Organ Failure Assessment (qSOFA) score 5, 6: a scoring system used to predict mortality and sepsis in patients with a suspected infection
• modified National Early Warning Score (mNEWS) 5: a scoring system used to predict mortality and sepsis in patients with a suspected infection

Performance of Scoring Systems

The performance of these scoring systems varies:

• PERC rule: has a negative likelihood ratio of 0.21 (95% CI: 0.12-0.38) for predicting PE overall, and 0.63 (95% CI: 0.38-1.06) in low-risk patients 2
• mNEWS: has the highest sensitivity (91.18%) and area under the receiver operating characteristic curve (AUC) (0.607) for predicting 30-day mortality 5
• qSOFA: has the highest specificity (83.67%) but poor sensitivity (19.82%) for identifying patients at risk of bacteraemia 6
• SIRS: has reasonable sensitivity (82.07%) but poor specificity (20.72%) for identifying patients at risk of bacteraemia 6

Clinical Application

These scoring systems can be used in the emergency department to:

• Exclude pulmonary embolism without further testing in low-risk patients using the PERC rule 3, 4
• Predict mortality and sepsis in patients with a suspected infection using mNEWS, qSOFA, and SIRS 5, 6
• Identify patients at risk of bacteraemia using the CEC SEPSIS KILLS pathway and other scoring systems 6