The immediate period after spinal cord injury (SCI) is one of the only opportunities that clinicians and care-givers have to make a real difference to patient outcomes. One of the main aims during this period is to preserve blood flow and oxygen delivery to the spinal cord to prevent any further damage from occurring after the injury. The heart acts as the major pump for blood to be pumped to the spinal cord and the body. It has been shown in small animal models and in humans with long-standing SCI that the ability of the heart to pump blood after injury is compromised, which may in turn reduce the amount of blood and oxygen delivered to the injured cord. It is unclear how quickly these changes occur in the heart following SCI and how best to manage heart function such that blood flow and oxygen delivery can be optimized. In the present study, the investigators will examine how the heart functions immediately after SCI. The findings from this study are expected to provide new information that could help clinicians improve the management of people who have just suffered a SCI.