Oxygen therapy delivery

Hyperbaric oxygen therapy involves the delivery of 100% oxygen at pressures in excess of normal atmospheric conditions. The intermittent application of hyperbaric hyperoxia is associated with direct and indirect antibacterial effects, angiogenesis in partially ischemic tissue, tissue hyperoxygenation, " vasoconstriction without component hypoxia, and... 

Mixed respiratory and metabolic acidosis should be treated by responding to both the respiratory and metabolic acidosis. Improved oxygen delivery must be initiated to improve hypercarbia and hypoxia. Mechanical ventilation can be needed to reduce PaC02. During initial therapy, appropriate amounts of alkali should be given to reverse the metabolic acidosis. 

Rinsch, C., Regulier, E., Deglon, N., Dalle, B., Beuzard, Y. and Aebischer, P. (1997) A gene therapy approach to regulated delivery of erythropoietin as a function of oxygen tension. Hum. Gene Ther., 8, 1881-1889. 

Correct answer = D. It is important to increase the cardiac output to improve oxygen delivery and thus minimize anaerobic metabolism and improve CNS and renal perfusion. Since this patient apparently does not have a heart condition, such as congestive heart failure, she could benefit from fluid therapy. An inotropic agent, such as dopamine, would lead to an increased cardiac output and dilation of the renal vasculature. [Note At high doses, however, it may constrict the renal beds due to interaction on a receptors.] Antibiotic administration is also important but will not improve the patient s hemodynamics. 

In two other trials, one in the United States and the other in Europe, DCLHb was tested in trauma and hemorrhagic shock patients as an adjunct to the current therapies for enhancing oxygen delivery fluids, blood, and operative intervention. In the multicenter, randomized, controlled, single-blinded efficacy trial conducted at 18 U.S. trauma centers from Feb 1997 to Jan 1998, patients with presumed or proven hemorrhage and persistent hypoperfusion were treated with DCLHb or normal saline (control) solution. Although there were no restrictions in the use of fluids, blood, or any other intervention prior to enrollment in this study, once enrolled, the patient received 500 ml of the treatment solution no later than 30 min after first... 

The main goal of fluid therapy is to increase cardiac output by increasing and then maintaining cardiac preload (Starling s law of the heart). This, in turn, increases oxygen delivery to the tissues. By selecting fluids with the appropriate electrolyte content, it is also possible to correct electrolyte and add-base disturbances. 

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