[47] Patients with cystic fibrosis (CF) referred for LT present a unique challenge. In addition to being at risk for development of HPS and PPHN, the severity of CF-related lung disease can impact outcome. The forced expiratory volume in one second (FEV1) and forced vital capacity (FVC) have been used in a

model to predict Navitoclax survival.[48] FEV1 was found to be lower in CF patients with liver disease who subsequently receive LT than those who do not undergo LT and is used to monitor improvement following LT.[49] 13. Screening transcutaneous oxygen saturation with the patient in the upright position should be performed in all patients with possible portosystemic shunting. (2-B) 14. Two-dimensional echocardiography (2-DE) with Doppler should be performed in all patients at the time of liver transplant evaluation (2-B); if the right ventricular systolic pressure is over 50 mmHg by 2-DE, a right-heart cardiac catheterization

is necessary to establish the diagnosis of porto-pulmonary hypertension. (2-B) 15. Pulmonary function tests, including forced expiratory volume in one second and forced vital capacity should be performed in patients with cystic fibrosis evaluated for liver transplant. (2-B) Glomerular filtration rate (GFR) is the most practical measure of kidney function.[50] Direct measurement of GFR using an exogenous see more filtration marker, such as iohexol plasma clearance, is impractical in the routine clinical setting.[51] Endogenous filtration markers, such as creatinine clearance, enough are hampered by the imperfections of timed urinary collections. Static measurements of naturally filtered molecules, such as creatinine, are affected by muscle mass, age, and gender as well as renal tubular absorption and secretion. At best, only an estimate of the GFR can be achieved. Serum creatinine, while imperfect, is most often used to screen individuals for evidence of renal insufficiency,

but cannot be used to estimate GFR independently. The recently revised Schwartz Formula utilizes the serum creatinine (sCr), patient height, and a “constant” to derive an estimated creatinine clearance (eCCL) and is easily used at the bedside.[51] The formula is 0.413 × [sCr (mg/dL) / height (cm)] = GFR (mL/min/1.73 m2). Cystatin C is a low molecular weight protein that is almost completely filtered by the glomerulus, is not excreted or absorbed by the renal tubules, and is not affected by muscle mass, age, or gender.[52] Normal values for cystatin C are high in infants but approach normal adult levels (0.51-0.98 mg/L) by 1 year of age.[53] A cystatin C level of 1.06 mg/L predicted a GFR <80 mL/min/1.