10. Pregnancy (excluded from CPM portion only) a. Rationale: Pregnant patients can develop the supine hypotensive syndrome (where the uterus compromises venous return due to compression of the IVC). This typically occurs only after 20 weeks gestation. To assure safety, any patient who self identifies as pregnant or has a positive urine pregnancy test on admission will not be offered CPM since it requires extended periods in the supine position.