If the respiratory acidosis is chronic, the body will respond by trying to excrete acid and retain bicarbonate in the urine resulting in a compensatory rise in serum bicarbonate. a significant ventilation/perfusion imbalance.depression of the breathing centre in the brain.Respiratory acidosis occurs when the pCO2 is abnormally high. Thus a decrease in pH from 7.0 to 6.0 represents a ten-fold increase in. The pH is a negative logarithm of hydrogen ion concentration, normal range 7.35-7.45. Venous sites - (from an intravenous cannula) more accurate from umbilical vein catheter (UVC) or central venous catheter (CVC) than peripheral IV.Ĭapillary sites - (heel prick) specimens are the least useful, particularly if the baby has decreased perfusion or is cold.

It is always important to note the FiO2 (percentage inspired oxygen) when interpreting blood gases. Arterial specimens are required to assess pO2. We recommend that you also refer to more contemporaneous evidence in the interim.īlood gases are helpful to determine the adequacy of respiratory function (oxygenation and ventilation) as well as the baby's acid-base balance.īlood gases can be taken from the following sites:Īrterial sites - either a peripheral arterial stab or an indwelling arterial line, arterial stabs may be taken from the radial artery (provided there is also a palpable ulnar pulse) or from the brachial artery, although this is in close proximity to the median nerve. Please note that all guidance is currently under review and some may be out of date.

Ph 7.18