Background and Aims Acute pain increases vital signs and is measured by the Manchester pain scale during triage. This multicentre observational study aims to determine associations between respiratory rates or heart rates and Manchester pain scores and to derive age and pain appropriate centiles for children presenting at emergency departments (EDs).

Methods Triaged children (< 16 years) presented at EDs in Rotterdam between 2006 and 2010, in The Hague between 2006 and 2007, and in London in 2010, were included. Pain scores were obtained by the Manchester painscale (range 0–10). This painscale combines a visual analogue scale, a verbal descriptor scale, and a pain behaviour tool. Univariate and multivariable regression analyses were performed. Secondly, pain and age appropriate heart rate and respiratory rate centile charts were created.

Results We included 45344 children. In multivariable analysis, the average heart rate of children with mild or moderate pain decreased significantly with 6.1 (95%CI5.2–6.9) and 5.0 (95%CI3.9–6.1) beats per minute respectively, while children with severe pain had increased heart rates (6.5.95%CI4.5–8.6) when compared with children without pain. Centile charts for children younger than twelve years showed increased heart rates for children with severe pain. This effect disappeared in older children. The association between respiratory rates and pain scores showed similar trends as heart rate centiles, but the change in respiratory rates was small.

Conclusion New derived centile charts for children are available to interpreted heart rates and respiratory rates in relation to pain. In younger children, heart rates increased due to severe pain.