title: 'Six sigma approach' - an objective strategy in digital assessment of postoperative air leaks: a prospective randomised study.
abstract: OBJECTIVE
  Until now, only way to report air leaks (ALs) has been with an analogue score in an inherently subjective manner. The Six Sigma quality improvement methodology is a data-driven approach applicable to evaluate the quality of the quantification method of repetitive procedures. We applied the Six Sigma concept to improve the process of AL evaluation.
  
  
  METHODS
  A digital device for AL measurement (Drentech PALM, Redax S.r.l., Mirandola (MO), Italy) was applied to 49 consecutive patients, who underwent pulmonary intervention, compared with a similar population with classical chest drainage. Data recorded were postoperative AL, chest-tube removal days, number of chest roentgenograms, hospital length of stay; device setup time, average time rating AL and patient satisfaction. Bivariable comparisons were made using the Mann-Whitney test, the χ² test and Fisher's exact test. Analysis of quality was conducted using the Six Sigma methodology.
  
  
  RESULTS
  There were no significant differences regarding AL (p=0.075), although not statistically significant; there was a reduction of postoperative chest X-rays (four vs five) and of hospital length of stay (6.5 vs 7.1 days); and a marginally significant difference was found between chest-tube removal days (p=0.056). There were significant differences regarding device setup time (p=0.001), average time rating AL (p=0.001), inter-observer variability (p=0.001) and patient satisfaction (p=0.002). Six Sigma analyses revealed accurate assessment of AL.
  
  
  CONCLUSIONS
  Continuous digital measurement of AL reduces degree of variability of AL score, gives more assurance for tube removal, and reports AL without the apprehension of observer error. Efficiency and effectiveness improved with the use of a digital device. We have noted that the AL curves depict actually sealing of AL. The clinical importance of AL curves requires further study.
authors.affiliation: Thoracic Surgery Unit, S. Croce e Carle City Hospital, Cuneo, Italy. luca.bertolaccini@unito.it
authors.forename: Luca
authors.initials: L
authors.lastname: Bertolaccini
authors.forename: Giovanna
authors.initials: G
authors.lastname: Rizzardi
authors.forename: Mary Jo
authors.initials: MJ
authors.lastname: Filice
authors.forename: Alberto
authors.initials: A
authors.lastname: Terzi
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D015505:Chest Tubes; D020878:Device Removal; D005260:Female; D005541:Forced Expiratory Volume / Q000502:physiology; D006801:Humans; D007558:Italy; D007902:Length of Stay / Q000706:statistics & numerical data; D008168:Lung / Q000601:surgery; D008297:Male; D008875:Middle Aged; D017060:Patient Satisfaction; D011030:Pneumothorax / Q000175:diagnosis* / Q000503:physiopathology / Q000628:therapy; D011182:Postoperative Care / Q000295:instrumentation / Q000379:methods / Q000592:standards; D011183:Postoperative Complications / Q000175:diagnosis* / Q000503:physiopathology / Q000628:therapy; D011446:Prospective Studies; D058996:Quality Improvement; D055815:Young Adult