Arterial, venous and capillary blood gas measurement in newborn at the NICU.

In NICU arterial blood gas sampling is the golden standerd to monitor
ventilated patients.
Arterial access is not always technical possible and should always be well
weighed against complications as trombosis, infection and ischemia.
In absence of arterial access, capillary blood gasses are used in standard of
care. Because venous blood gasses are said to be unreliable, they are not used.
Even if due to other reason venous blood have to be drawn, a capillary blood
gas will be taken seperately.
In literature there is lack of evidence whether the different blood gasses are,
even partly, reliable enough to be used for clinical purposis.

The objective of this study is to investigate ABG, CBG and VBG (or parts of the
blood gas analysis) in infants.

This is a prospective observational single center study. In infants admitted to
the NICU who need blood gas monitoring, arterial, venous and capillary blood
gas will be performed simultaneously at the same time-point.

To minimize the burden for the patient we will do the following:
When venous access is needed for either intravenous medication or for blood
examination we will collect extra blood for venous blood gas at the same time.
We do not perform an extra puncture.
We will limit the number of simultaneously drawn blood gas samples to a maximum
of 5 paired samples (e.g. venous versus arterial and/or capillary) and a
maximum of 3 extra capillary punctures to minimize the burden per patient.

All punctures will be comforted with oral sucrosis following local protocol.