COMPARISON OF THE ACID-BASE STATUS OF BLOOD OBTAINED FROM INTRAOSSEOUS AND CENTRAL VENOUS SITES DURING STEADY-FLOW AND LOW-FLOW STATES

Objective: To compare the acid-base status of blood obtained from the tibial intraosseous site with that status obtained from a central venous site during steady- and low-flow states in a piglet model. Design: A prospective, observational study Setting. Animal laboratory at a university medical center. Subjects: Nine 2-day-old piglets. Interventions: Animals were anesthetized, intubated, and mechanically ventilated. A thermodilution pulmonary artery catheter was inserted via the right internal jugular vein and directed into the pulmonary artery. An arterial catheter was inserted into the right carotid artery and an intraosseous needle was inserted into the proximal tibial marrow cavity. Cardiorespiratory arrest was induced by discontinuation of ventilation. The animals were subsequently resuscitated by precordial compressions and ventilation. Blood samples were obtained from central venous and intraosseous sites during steady state and during resuscitation (low-flow state). Results. No significant differences (p < .05) were found for pH, PCO2, and bicarbonate concentration when values that were obtained from the central venous and intraosseous sites were compared during steady- and low-flow states. Conclusions: The acid-base status of intraosseous blood is similar to that status of central venous blood. Intraosseous blood gas values may be an acceptable alternative to central venous blood gas values in judging central acid-base status during cardiopulmonary resuscitation.