Postoperative monitoring of segmental lung motion and of developed force in the diaphragm

Measuring systems were developed for continuous monitoring of diaphragmatic force development by a force probe and for continuous monitoring of pulmodynamics by core to surface electrical impedance. On 18 high risk patients, undergoing oesophageal surgery, recovery of diaphragmatic activity and global ventilation was studied during the early postoperative period. When analgesia weakend, developed force also diminished. The relation: Amplitude of the active force signal to amplitude of the impedance signaldecreased to less than 0.5. Adequate analgesia combined with physical therapy reencouraged the patients to enhance diaphragmatic activity. Different analgetic drugs showed different patterns of action on the diaphragma.