Relationship between mean arterial pressure and end-tidal partial pressure of carbon dioxide during hemorrhagic shock and volume resuscitation

Objectives. We examined the relationship between partial end-tidal CO(2) (pet) and mean arterial pressure in patients with traumatic hemorrhagic shock, who were receiving constant minute ventilation. Methods. In 61 patients we continuously measured pet CO(2) with a capnograph, direct arterial pressure via a cannula, oxygen levels via pulse oximetry and body temperature. Results. We observed significant changes in pet CO(2) (increase) after volume resuscitation and a quantitative linear relationship between pet CO(2) and mean arterial pressure. Conclusions. Partial end-tidal CO(2) can be used as a reliable non-invasive monitoring device in patients with hemorrhagic shock when minute ventilation is relatively constant. The monitoring of pet C02 might also be a useful guide for volume resuscitation in hemorrhagic shock, especially in the pre-hospital setting.