title: Modified rapid shallow breathing index adjusted with anthropometric parameters increases predictive power for extubation failure compared with the unmodified index in postcardiac surgery patients.
abstract: OBJECTIVE
  The aim of this study was to determine the best predictors of successful extubation after cardiac surgery, by modifying the rapid shallow breathing index (RSBI) based on patients' anthropometric parameters.
  
  
  METHODS
  Single-center prospective observational study.
  
  
  METHODS
  Two general intensive care units at a single research institute.
  
  
  METHODS
  Patients who had undergone uncomplicated cardiac surgery.
  
  
  METHODS
  None.
  
  
  RESULTS
  The following parameters were investigated in conjunction with modification of the RSBI: Actual body weight (ABW), predicted body weight, ideal body weight, body mass index (BMI), and body surface area. Using the first set of patient data, RSBI threshold and modified RSBI for extubation failure were determined (threshold value; RSBI: 77 breaths/min (bpm)/L, RSBI adjusted with ABW: 5.0 bpm×kg/mL, RSBI adjusted with BMI: 2.0 bpm×BMI/mL). These threshold values for RSBI and RSBI adjusted with ABW or BMI were validated using the second set of patient data. Sensitivity values for RSBI, RSBI modified with ABW, and RSBI modified with BMI were 91%, 100%, and 100%, respectively. The corresponding specificity values were 89%, 92%, and 93%, and the corresponding receiver operator characteristic values were 0.951, 0.977, and 0.980, respectively.
  
  
  CONCLUSIONS
  Modified RSBI adjusted based on ABW or BMI has greater predictive power than conventional RSBI.
authors.affiliation: Department of Anesthesiology, Yokohama City University Hospital, Japan. Electronic address: shunty5323@gmail.com.
authors.forename: Shunsuke
authors.initials: S
authors.lastname: Takaki
authors.affiliation: Department of Anesthesiology, National Heart Center in Malaysia (Institute Jantung Negara), Malaysia.
authors.forename: Suhaini Bin
authors.initials: SB
authors.lastname: Kadiman
authors.affiliation: Department of Anesthesiology, National Heart Center in Malaysia (Institute Jantung Negara), Malaysia.
authors.forename: Sharifah Suraya
authors.initials: SS
authors.lastname: Tahir
authors.affiliation: Department of Anesthesiology, National Heart Center in Malaysia (Institute Jantung Negara), Malaysia.
authors.forename: M Hassan
authors.initials: MH
authors.lastname: Ariff
authors.affiliation: Department of Anesthesiology, Yokohama City University Hospital, Japan.
authors.forename: Kiyoyasu
authors.initials: K
authors.lastname: Kurahashi
authors.affiliation: Department of Anesthesiology, Yokohama City University Hospital, Japan.
authors.forename: Takahisa
authors.initials: T
authors.lastname: Goto
mesh_terms: D000368:Aged; D060666:Airway Extubation / Q000009:adverse effects / Q000379:methods*; D000886:Anthropometry / Q000379:methods*; D006348:Cardiac Surgical Procedures / Q000639:trends*; D005260:Female; D005544:Forecasting; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012119:Respiration; D012121:Respiration, Artificial / Q000009:adverse effects / Q000379:methods*; D012129:Respiratory Function Tests / Q000379:methods; D017211:Treatment Failure; D015300:Ventilator Weaning / Q000009:adverse effects / Q000379:methods*
keywords: anthropometric parameters; cardiac surgery; postoperative care; rapid shallow breathing index