Transcutaneous oxygen monitors are reliable indicators of arterial oxygen tension (if used correctly).

The following recommendations should always be kept in mind: Each new transcutaneous equipment, or modification of equipment, must be adequately tested in vivo as well as in vitro. The users must have basic understanding of the principles and the major requirements for applying the tcPO2 technique. Calibration procedures must be carefully adhered to according to the manufacturer's instruction. The temperature of the electrode must be kept at 44 degrees C for premature infants and at 44 degrees or 45 degrees C for term infants if the clinical aim is to estimate arterial PO2 levels. Resetting of the electrode must then be done every two hours. For sick infants, this may be needed more frequently. Whenever there is cause to compare tcPO2 values with arterial ones, the latter must be obtained from an appropriate vessel. Great care must be taken when drawing and analyzing blood for PO2. The infant should not be crying. Significantly lower transcutaneous PO2 values than arterial PO2 values are due to either one or several of the errors indicated above or to an insufficient circulation under the electrode. In recent years, technical or clinical errors seem to have become more and more common. Thereby the technique has unjustly fallen into disrepute. Insufficient circulation under the electrode rarely occurs in the newborn infant and then only in those who are in overt shock.