Heel Warming Before Capillary Blood Sampling

Some infants experience a difficult and painful blood sampling which can lead to bruised or swollen heels and a blood sample of poor quality. To minimize the risk of that, the infant's heel is heated before the procedure as described in standard GP42-A6 from The Clinical and Laboratory Standards Institute. However, no consensus exists on which heating method to use. The aim of this study is to compare three different heating methods in terms of which method can help reduce pain experienced by infants as well as increase the quality of the blood samples.

Infants (postmenstrual age ≥ 28 + 0) admitted to the NICU, Kolding Hospital and having a blood sample taken by a Biomedical Laboratory Scientist are invited to participate. A parental informed concent must be signed by both parents before participation.

Infants are randomized to one of the three heating methods: glove, blanket or gel pad.

The following blood sampling procedure is closely monitored to register data corresponding to the five outcome measures.

Furthermore the infants personal data, location of the infant during the procedure, surface temperature of the heel before and after heating, volume of sampled blood, sign of bruises and swelling as well as hematocrit are registered.

Data registration, web-based block randomization, data storage and statistical analysis are supported by OPEN (Open Patient data Explorative Network, University of Southern Denmark).

The study is registered as public research at the Region of Southern Denmark (journal no. 20/1316) and is approved by The Regional Committees on Health Research Ethics for Southern Denmark (ID S-20200082).

Inclusion criteria

• PMA (postmenstrual age) ≥ 28+0
• Blood sampling performed by a Biomedical Laboratory Scientist

Exclusion criteria

• GA (gestational age) ≥ 44+0
• Weight > 6000 g
• Coagulation related disorder
• Severe illness/disorder
• Heel is bruised or swollen
• Parents not understanding written Danish language