Mews

MEWS, or Modified Early Warning Score, is a physiological scoring system used in hospital settings to identify patients at risk of clinical deterioration. It aggregates routinely monitored vital signs into a numerical score that triggers escalation of care when thresholds are reached.

Commonly, MEWS uses five parameters: respiratory rate, heart rate, systolic blood pressure, temperature, and level of consciousness. Each parameter is assigned a score from 0 to 3 based on how far the measurement deviates from normal ranges. The scores are summed to yield a total MEWS, with higher values indicating greater risk. Some versions may incorporate additional factors such as oxygen saturation, supplemental oxygen requirement, or urine output.

MEWS is used to guide clinical decisions, including more frequent observation, involvement of a nurse manager or rapid response team, or transfer to higher levels of care. It is often applied on medical and surgical wards and can be integrated into paper charts or electronic health records. Thresholds for escalation vary by institution, but a typical rule is that a MEWS above a certain score prompts review within a set time.

MEWS is related to other early warning systems, such as the National Early Warning Score (NEWS); NEWS adds oxygen saturation and oxygen therapy requirements and is used in some regions as a standardized national tool. MEWS is an earlier, simpler system with regional adaptations.

Limitations include variable predictive performance across populations, potential for alarm fatigue, and reliance on consistent measurement. Proper staff training and protocol-defined escalation steps are essential for effectiveness.