A pressure-sensing catheter for detecting pressure changes within a cavity of a patient, comprising: an elongate member comprising a proximal end, a distal end and a central lumen extending from the proximal end to the distal end; a first monitor lumen positioned within the elongate member between the central lumen and a wall of the elongate member, the first monitor lumen extending from the proximal end to the distal end; and, a first pressure-compliant member defining an interior chamber, the first pressure-compliant member being hollow and in fluid communication with the first monitor lumen, the first pressure-compliant member being disposed about an exterior of the elongate member, wherein the first monitor lumen and the interior chamber of the first pressure-compliant member define a fluid column, characterized in that the first monitor lumen has a volume of 25 microliters to 40 microliters; and the pressure sensing catheter further comprises: a connector apparatus disposed about the proximal end and in fluid communication with the first monitor lumen, the connector apparatus comprising a first complementary connector and a second complementary connector, the first complementary connector and the second complementary connector being connectable to each other in a complementary fashion, at least one of the first complementary connector and the second complementary connector (72, 98) being fluidly coupled to the fluid column, one of the first complementary connector and the second complementary connector (72, 98) comprising a pressurizing device and the other of the first complementary connector and the second complementary connector (72, 98) comprising a bore (114, 122), wherein coupling the first complementary connector and the second complementary connector causes the pressurizing device to displace a volume of fluid located within the bore (114, 122) into the fluid column, wherein a ratio of a volume of displaced fluid to the volume of the fluid column is at least about 1:2 and less than about 1:1. an elongate member comprising a proximal end, a distal end and a central lumen extending from the proximal end to the distal end; a first monitor lumen positioned within the elongate member between the central lumen and a wall of the elongate member, the first monitor lumen extending from the proximal end to the distal end; and, a first pressure-compliant member defining an interior chamber, the first pressure-compliant member being hollow and in fluid communication with the first monitor lumen, the first pressure-compliant member being disposed about an exterior of the elongate member, wherein the first monitor lumen and the interior chamber of the first pressure-compliant member define a fluid column, characterized in that the first monitor lumen has a volume of 25 microliters to 40 microliters; and the pressure sensing catheter further comprises: a connector apparatus disposed about the proximal end and in fluid communication with the first monitor lumen, the connector apparatus comprising a first complementary connector and a second complementary connector, the first complementary connector and the second complementary connector being connectable to each other in a complementary fashion, at least one of the first complementary connector and the second complementary connector (72, 98) being fluidly coupled to the fluid column, one of the first complementary connector and the second complementary connector (72, 98) comprising a pressurizing device and the other of the first complementary connector and the second complementary connector (72, 98) comprising a bore (114, 122), wherein coupling the first complementary connector and the second complementary connector causes the pressurizing device to displace a volume of fluid located within the bore (114, 122) into the fluid column, wherein a ratio of a volume of displaced fluid to the volume of the fluid column is at least about 1:2 and less than about 1:1. a connector apparatus disposed about the proximal end and in fluid communication with the first monitor lumen, the connector apparatus comprising a first complementary connector and a second complementary connector, the first complementary connector and the second complementary connector being connectable to each other in a complementary fashion, at least one of the first complementary connector and the second complementary connector (72, 98) being fluidly coupled to the fluid column, one of the first complementary connector and the second complementary connector (72, 98) comprising a pressurizing device and the other of the first complementary connector and the second complementary connector (72, 98) comprising a bore (114, 122), wherein coupling the first complementary connector and the second complementary connector causes the pressurizing device to displace a volume of fluid located within the bore (114, 122) into the fluid column, wherein a ratio of a volume of displaced fluid to the volume of the fluid column is at least about 1:2 and less than about 1:1.