title: [Prevalence of diaphragmatic paralysis after brachial plexus blockade by the posterior approach with 0.2% ropivacaine.].
abstract: OBJECTIVE
  Brachial plexus blockade by the interscalene approach, described by Winnie, is one of the most effective techniques in promoting postoperative analgesia in surgeries of the shoulder. Diaphragmatic paralysis is one of the consequences of this technique. This paralysis can cause respiratory failure in patients with prior lung dysfunction. Brachial plexus blockade by the posterior approach has become increasingly more popular. The objective of this study was to determine the prevalence of diaphragmatic paralysis after interscalene brachial plexus blockade by the posterior approach with 0.2% ropivacaine.
  
  
  METHODS
  Twenty-two patients who underwent interscalene brachial plexus blockade by the posterior approach with 0.2% ropivacaine were evaluated in the postoperative period to identify radiological signs of elevation of the hemidiaphragm that could suggest hemidiaphragmatic paralysis. Forty mL of 0.2% ropivacaine were used in 20 patients; inspiratory chest X-rays were done in these patients. Twenty mL of 0.2% ropivacaine were used in two patients, with posterior fluoroscopic evaluation.
  
  
  RESULTS
  There were no complications related to the procedure. The anesthesia was effective in every patient, providing good postoperative analgesia. Every patient in this study presented elevation of the diaphragm compatible with hemidiaphragmatic paralysis.
  
  
  CONCLUSIONS
  We observed that brachial plexus blockade by the posterior approach is associated with a high prevalence of diaphragmatic paralysis, even with low concentrations of local anesthetics.
authors.affiliation: Hospital Lifecenter.
authors.forename: Marcos Guilherme Cunha
authors.initials: MG
authors.lastname: Cruvinel
authors.forename: Carlos Henrique Viana de
authors.initials: CH
authors.lastname: Castro
authors.forename: Yerkes Pereira
authors.initials: YP
authors.lastname: Silva
authors.forename: Roberto Cardoso
authors.initials: RC
authors.lastname: Bessa Júnior
authors.forename: Flávio de Oliveira
authors.initials: Fde O
authors.lastname: França
authors.forename: Flávio
authors.initials: F
authors.lastname: Lago