title: The importance of pleural integrity for effective and safe thoracic paravertebral block: a retrospective comparative study on postoperative pain control by paravertebral block.
abstract: OBJECTIVE
  Recently, paravertebral block (PVB) has been reported to be an effective analgesic modality for post-thoracotomy pain, but there is no consensus on how thoracic PVB can be more effective. Our hypothesis that intact pleura has a significant impact on the analgesic effectiveness of thoracic PVB was evaluated.
  
  
  METHODS
  Data of patients who underwent general thoracic surgery [thoracotomy or video-assisted thoracic surgery (VATS)] and paravertebral catheterization at Nagara Medical Center between April 2010 and March 2013 were collected. To compare the frequency of non-steroidal anti-inflammatory drugs taken as well as the usage of rescue pain medications between patients with pleural disruption and those without, data were analysed after matching on propensity scores. Covariates for match estimation were age, sex, body mass index, American Society of Anesthesiologists score, diagnosis, operative details and local anaesthesia infused.
  
  
  RESULTS
  There were 278 patients who underwent general thoracic surgery and paravertebral catheterization. The propensity score-matching process created 78 matched patients with pleural disruption and those without. Based on the propensity score matching, a significant increase in the frequency of non-steroidal anti-inflammatory drugs taken on postoperative day 1 and in the usage of rescue drugs was observed in patients with pleural disruption.
  
  
  CONCLUSIONS
  According to our analysis, creating a sub-pleural space without pleural disruption is essential for quality thoracic PVB.
authors.affiliation: Department of General Thoracic Surgery, Kyoto University Hospital, Kyoto, Japan tk.thoracic@gmail.com.
authors.forename: Teruya
authors.initials: T
authors.lastname: Komatsu
authors.affiliation: Department of General Thoracic Surgery, Kyoto University Hospital, Kyoto, Japan.
authors.forename: Terumasa
authors.initials: T
authors.lastname: Sowa
authors.affiliation: Department of Anesthesiology, Nagara Medical Center, Gifu, Japan.
authors.forename: Atsunari
authors.initials: A
authors.lastname: Kino
authors.affiliation: Department of General Thoracic Surgery, Nagara Medical Center, Gifu, Japan.
authors.forename: Takuji
authors.initials: T
authors.lastname: Fujinaga
mesh_terms: D000700:Analgesics / Q000627:therapeutic use*; D002404:Catheterization; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D009407:Nerve Block / Q000379:methods*; D010147:Pain Measurement; D010149:Postoperative Pain / Q000175:diagnosis / Q000628:therapy*; D010994:Pleura / Q000601:surgery*; D012189:Retrospective Studies; D013896:Thoracic Diseases / Q000601:surgery*; D020775:Thoracic Surgery, Video-Assisted / Q000009:adverse effects*; D013904:Thoracic Vertebrae; D016896:Treatment Outcome
chemical_list: D000700:Analgesics
keywords: Paravertebral block; Pleural disruption; Postoperative pain management; Thoracic analgesia