To determine the equivalency of pressure measurements from peripherally inserted central catheters(PICCs) versus centrally inserted central venous catheters(CVCs) in vitro as well as in vivo. The in vitro study was performed in a clinical laboratory. Static pressure measurements from PICCs and CVCs were obtained in vitro over a physiologic range of 5–25 mmHg. Triple and dual lumen PICCs were directly compared to CVC controls.Dynamic pressure waveforms were recorded to simulate physiologic intravascular pressure variation. The in vivo study was executed in the medical intensive care unit(MICU) of a tertiary-level academic medical center. Data was collected from ten adult patients with both a PICC and a CVC in place for on-going clinical care. Measurements of central venous pressure (CVP) were recorded simultaneously from PICCs and CVCs. Duplicate measurements were taken after a stable waveform was recorded. For the in vitro study, a total of 540 pressure measurements were recorded. The average bias determined by Bland–Altman plot was 0 mmHg for the 5Fr PICC and 0.071 mmHg for the 6Fr PICC. The correlation coefficient for both catheters was 1.0 (P<0.001). Dynamic pressure waveforms revealed equivalent amplitude. During the in vivo trial, 70CVP measurements were collected. The paired CVP measurements were found to be highly reliable across subjects (r = 0.99, P<0.0001). No significance in the average difference in CVP measurement (PICC–CVC) was determined by the Wilcoxon Signed Rank test (S = 1,P = 0.93). In conclusion, PICCs are equivalent to CVCs when measuring static and dynamic pressure in vitro and CVP in ICU patients.