The invention provides a fluid management system (1) for providing fluid from a fluid source (20) to the body of a patient. The fluid management system (1) includes a compressible chamber (10). A fluid conduit (30) is in fluid communication with the fluid source (20) and with an interior of the compressible chamber (10). A bypass conduit (40) has an inlet end (43) in fluid communication with the fluid source (20) and an outlet end (44) for providing fluid to a trocar (70). The bypass conduit 40 passes either through or around the compressible chamber (10). A first one way valve (80) can admit fluid from the fluid conduit (30) into the interior of the compressible chamber (10). A second one way valve (90) can admit fluid within the interior of the compressible chamber (10) into the bypass conduit (40). A portion (46) of the bypass conduit (40) upstream of the second one way valve (90) is collapsible under the force of selectively applied external pressure when the compressible chamber (10) is at least partially filled with fluid from the fluid source (20), so as to selectively close off the bypass conduit (40) upstream of the second one way valve (90).