The flow-volume loop in tetraplegics

We have studied the FVC and maximum flow-volume loop in 20 tetraplegics and the results have been compared with the predicted normal values. The FVC in sitting position is reduced at approximately half the normal predicted values and is significantly lower than in supine and Trendelenburg. At high lung volumes the flows are reduced at half the normal values. At low lung volumes the reduction is smaller (71.5 per cent).