Objectives: To determine the agreement of fingertip and sternum capillary refill time (CRT) in children.
Design: Prospective, method-comparison study.
Setting: Single children's emergency department, UK PARTICIPANTS: 92 children aged 0-12 years, with clinical observations within normal ranges for their age, no relevant medical history and presenting to hospital with a minor illness or injury.
Main outcome measures: Agreement between fingertip and sternum CRT measurements.
Results: Fingertip CRT ranged from 0.05 to 2.78 s with a mean of 1.08±0.44 and sternum CRT ranged from 0.85 to 2.38 s with a mean of 1.5±0.33. There was a significant difference between fingertip and sternum CRT (t=-9.2, df=91, p=<0.001) and a weak association between the two measurements (r=0.18, p=0.9). A Bland Altman comparison showed the mean difference between fingertip and sternum CRT was -0.49±0.51 with an upper and lower limit of agreement ranging from -1.5 (95% CI -1.69 to -1.32) to 0.53 (95% CI 0.34 to 0.71).
Conclusions: Measurements of CRT taken at the fingertip and sternum are not comparable. Fingertip CRT was faster than sternum CRT. Normal CRT is 2-3 s. The current study questions the usefulness of CRT in the assessment of circulation in children.