title: A systematic review and meta-analysis of cohort studies of echocardiographic findings in OSA children after adenotonsilectomy.
abstract: BACKGROUND
  There is evidence that OSA in children can be associated with acute and chronic effects on the cardiovascular system due to repetitive episodes of apnea and hypoxemia.
  
  
  OBJECTIVE
  To assess whether there is an association between OSA and echocardiographic findings in children and whether that association persists after adenotonsillectomy.
  
  
  METHODS
  A literature search was conducted based on PUBMED, EMBASE and LILACS.
  
  
  METHODS
  Children with OSA and children who did not have OSA, who were aged ≤12 years.
  
  
  METHODS
  Two reviewers extracted data independently; the risk of bias was assessed by examining the selected sample, the recruitment method, completeness of follow up, and blinding.
  
  
  RESULTS
  Seven studies met all the inclusion criteria and methodological requirements. There was a significant difference with elevated mean pulmonary arterial pressure levels in OSA participants compared to those without OSA at preoperative assessment [mean difference (MD) 8.67; confidential interval (CI) 95% 6.09, 11.25]. OSA participants showed a statistically significant increased interventricular septum (IVS) thickness (mm) [MD 0.60; CI 95% 0.09, 1.11]; and right ventricular (RV) dimension (cm/m) [MD 0.19; CI 95% 0.10, 0.28]. There was also a significant increase in right ventricular (RV) dimension (cm/m) [MD 0.10; CI 95% 0.05, 0.14] in OSA children.
  
  
  CONCLUSIONS
  There is moderate quality evidence regarding possible association between OSA and right heart repercussions. More prognosis studies are needed, to allow the combination of results in a meta-analysis.
authors.affiliation: Otolaryngology, Botucatu Medical School, Univ Estadual Paulista-UNESP, Botucatu, SP, Brazil.
authors.forename: Silke Anna Theresa
authors.initials: SA
authors.lastname: Weber
authors.affiliation: Botucatu Medical School, Univ Estadual Paulista-UNESP, Botucatu, SP, Brazil.
authors.forename: Raíssa
authors.initials: R
authors.lastname: Pierri Carvalho
authors.affiliation: Cochrane Prognosis Group, Sydney Children's Hospital Network, Sydney, NSW, Australia.
authors.forename: Greta
authors.initials: G
authors.lastname: Ridley
authors.affiliation: Cochrane Prognosis Group, University of Melbourne, Parkville, VIC, Australia; Royal Children's Hospital Melbourne, Parkville, VIC, Australia; Murdoch Children's Research Institute, Parkville, VIC, Australia.
authors.forename: Katrina
authors.initials: K
authors.lastname: Williams
authors.affiliation: Evidence-Based Medicine Unit, Anaesthesiology Department, Botucatu Medical School, Univ Estadual Paulista-UNESP, Sao Paulo, SP, Brazil; McMaster Institute of Urology, McMaster University, Hamilton, Canada. Electronic address: eldib@fmb.unesp.br.
authors.forename: Regina
authors.initials: R
authors.lastname: El Dib
mesh_terms: D000233:Adenoidectomy; D002648:Child; D004452:Echocardiography; D006346:Heart Septum / Q000000981:diagnostic imaging; D006801:Humans; D006976:Hypertension, Pulmonary / Q000150:complications; D017380:Hypertrophy, Right Ventricular / Q000150:complications / Q000000981:diagnostic imaging; D020181:Sleep Apnea, Obstructive / Q000150:complications / Q000601:surgery*; D014068:Tonsillectomy
keywords: Echocardiographic findings; Meta-analysis; Obstructive sleep apnea; Prognosis studies; Systematic review