RAPID Score for Pleural Infection

Why Use

Pleural infection is a common condition with a high mortality with rising incidence in both adult and pediatric populations. Treatment options vary from very invasive, such as thoracic surgery, to simple treatment with antibiotics and/or intrapleural fibrinolytics. Determining which therapeutic approach is best for each patient can be challenging, as can predicting which patients are most likely to need extended stays in hospital. The RAPID Score is a robustly-developed risk model which has the potential to allow treatments to be more effectively targeted in pleural infection patients.

When to Use

Patient with pleural infection, defined by the presence of at least one of the following: Purulent fluid. Positive bacterial culture in fluid. Positive result for bacteria on Gram staining in fluid. Fluid pH <7.2, measured using a blood gas analyzer.

Formula

Pearls / Pitfalls

Based on trials done in the UK only, so extrapolation to different populations may not be accurate. Although technically externally validated by MIST2, this was not the intended purpose of the study. A large prospective validation study for RAPID is underway. Although the score seems to be able to reliably stratify patients into low, moderate and high risk categories, there is no clear indication for changing treatment exists yet. Purulence confers decreased mortality, which is counter to some other studies. The authors observed that purulent collections were less likely to have loculations and were therefore more amenable to complete drainage.

Management

It is not yet known how best to manage patients based on RAPID Score; however: Patients who are low risk may be better candidates for invasive surgical therapy, including thoracotomy or video-assisted thoracoscopic surgery (VATS). Some higher risk patients may benefit from earlier aggressive intervention to minimize the chances of poor outcomes. Higher risk patients who are sicker at presentation may be better suited for less invasive therapies like tube thoracostomy and fibrinolytics. Knowledge of the RAPID Score may help physicians advise patients and family members regarding the likely duration of stay in hospital and, if appropriate, their risk of mortality.

Critical Actions

The RAPID Score has yet to be prospectively validated in a large trial setting and so its role in routine clinical care is not fully formed. Clinical decisions regarding the treatment of pleural infection must always be taken with local variability in mind, especially relating to the availability of thoracic surgery and knowledge of likely causative organisms. The RAPID Score does not dictate treatment, but rather gives better information about the patient at presentation.

Advice

Factors associated with high risk scores include gram-negative rod infections, heart disease, diabetes, cancer, lung disease, and increased length of stay. Consider erring on the side of caution in patients with these.

More Information

Interpretation: RAPID Score Risk 3-month mortality* 0–2 Low 1.5% 3–4 Medium 17.8% 5–7 High 47.8% *From validation study, White 2015 .