title: Increased Rate of Poor Laryngoscopic Views in Patients Scheduled for Cardiac Surgery Versus Patients Scheduled for General Surgery: A Propensity Score-Based Analysis of 21,561 Cases.
abstract: OBJECTIVE
  Former analyses reported an increased rate of poor direct laryngoscopy view in cardiac surgery patients; however, these findings frequently could be attributed to confounding patient characteristics. In most of the reported cardiac surgery cohorts, the rate of well-known risk factors for poor direct laryngoscopy view such as male sex, obesity, or older age, were increased compared with the control groups. Especially in the ongoing debate on anesthesia staff qualification for cardiac interventions outside the operating room a detailed and stratified risk analysis seems necessary.
  
  
  METHODS
  Retrospective, anonymous, propensity score-based, matched-pair analysis.
  
  
  METHODS
  Single-center study in a university hospital.
  
  
  METHODS
  No active participants. Retrospective, anonymous chart analysis.
  
  
  METHODS
  The anesthesia records of patients undergoing cardiac surgery in a period of 6 consecutive years were analyzed retrospectively. The results were compared with those of a control group of patients who underwent general surgery. Poor laryngoscopic view was defined as Cormack and Lehane classification grade 3 or 4.
  
  
  RESULTS
  The records of 21,561 general anesthesia procedures were reviewed for the study. The incidence of poor direct laryngoscopic views in patients scheduled for cardiac surgery was significantly increased compared with those of the general surgery cohort (7% v 4.2%). Using propensity score-based matched-pair analysis, equal subgroups were generated of each surgical department, with 2,946 patients showing identical demographic characteristics. After stratifying for demographic characteristics, the rate of poor direct laryngoscopy view remained statistically significantly higher in the cardiac surgery group (7.5% v 5.7%).
  
  
  CONCLUSIONS
  Even with stratification for demographic risk factors, cardiac surgery patients showed a significantly higher rate of poor direct laryngoscopic view compared with general surgery patients. These results should be taken into account for human resource management and distribution of difficult airway equipment, especially when cardiac interventional programs are implemented in remote hospital locations.
authors: Department of Anesthesiology, University Hospital Erlangen, Erlangen, Germany. Electronic address: sebi_heinrich@gmx.de.
authors: Sebastian
authors: S
authors: Heinrich
authors: Department of Anesthesiology, University Hospital Erlangen, Erlangen, Germany.
authors: Andreas
authors: A
authors: Ackermann
authors: Department of Anesthesiology, University Hospital Erlangen, Erlangen, Germany.
authors: Johannes
authors: J
authors: Prottengeier
authors: Department of Anesthesiology, University Hospital Erlangen, Erlangen, Germany.
authors: Ixchel
authors: I
authors: Castellanos
authors: Department of Anesthesiology, University Hospital Erlangen, Erlangen, Germany.
authors: Joachim
authors: J
authors: Schmidt
authors: Department of Anesthesiology, University Hospital Erlangen, Erlangen, Germany.
authors: Jürgen
authors: J
authors: Schüttler
mesh_terms: D000368:Aged; D000768:Anesthesia, General / Q000009:adverse effects / Q000639:trends*; D001071:Appointments and Schedules; D006348:Cardiac Surgical Procedures / Q000009:adverse effects / Q000639:trends*; D005260:Female; D006801:Humans; D007828:Laryngoscopy / Q000009:adverse effects / Q000639:trends*; D008297:Male; D008875:Middle Aged; D057216:Propensity Score; D012189:Retrospective Studies; D013514:Surgical Procedures, Operative / Q000009:adverse effects / Q000639:trends
keywords: anesthesia for cardiac surgery; difficult airway; difficult laryngoscopy view; risk factor for difficult intubation