PLEURAL BUPIVACAINE PLACEMENT FOR OPTIMAL POSTTHORACOTOMY PULMONARY-FUNCTION - A PROSPECTIVE, RANDOMIZED STUDY

Objective: To determine dependent chest tube losses of bupivacaine wit h paravertebral versus interpleural administration, thereby helping to explain the significant differences in pulmonary function that exist between these two techniques. Design: A prospective, randomized study. Setting: A single hospital. Participants: Twelve adult patients under going posterolateral thoracotomies. Interventions: Paravertebral or in terpleural administration of bupivacaine. Measurements and Main Result s: Analgesia, as assessed by visual analog pain scores and patient-con trolled morphine requirements, was similar in both groups. Postoperati ve spirometric values were significantly better at most times with the paravertebral route of administration. Dependent chest tube bupivacai ne losses were approximately four times higher in the interpleural gro up. Conclusion: Local anesthetic on the diaphragm might actively impai r respiratory function through diaphragmatic and abdominal muscle weak ness, while failing to contribute to pain relief. Copyright (C) 1998 b y W.B. Saunders Company.