title: Postoperative pneumonia following cardiac surgery in non-ventilated patients versus mechanically ventilated patients: is there any difference?
abstract: BACKGROUND
  No studies have compared ventilator-associated pneumonia (VAP) and non-VAP following cardiac surgery (CS). The aim of this study was to assess the incidence, clinical and microbiologic features, treatment characteristics and prognosis of postoperative pneumonia following CS with a special focus on non-VAP.
  
  
  METHODS
  This was a retrospective cohort study based on a prospectively collected database. We compared cases of non-VAP and VAP following CS observed between January 2005 and December 2012. Statistical analysis consisted of bivariate and multivariate analysis.
  
  
  RESULTS
  A total of 257 (3.5%) of 7,439 consecutive CS patients developed postoperative pneumonia, including 120 (47%) cases of non-VAP. Patients with VAP had more frequent history of congestive heart failure (31% vs. 17%, P = 0.006) and longer duration of cardiopulmonary bypass (105 vs 76 min, P < 0.0001), than patients with non-VAP. No significant differences were observed between the 2 groups in terms of the types of microorganisms isolated with high proportions of Enterobacteriaceae (35%), Pseudomonas aeruginosa (20.2%) and Haemophilus spp (20.2%), except for a lower proportion of Methicillin-susceptible S. aureus in the non-VAP group (3.2% vs 7.9%, P = 0.03). In the intensive care unit, patients with non-VAP had lower sequential organ failure assessment scores than patients with VAP (8 ± 3 versus 9 ± 3, P = 0.004). On multivariate analysis, in-hospital mortality was similar in both groups (32% in the non-VAP group and 42% in the VAP group, adjusted Odds Ratio (aOR): 1.4; 95% confidence intervals (CI): 0.7-2.5; P = 0.34) and appropriate empiric antibiotic therapy was associated with a reduction of in-hospital mortality (aOR: 0.4; 95% CI: 0.2-1; P = 0.05). Piperacillin/tazobactam or imipenem monotherapy constituted appropriate empiric therapy in the two groups, with values reaching 93% and 95% with no differences between VAP and non-VAP cases.
  
  
  CONCLUSIONS
  Intensive care patients with VAP are more severely ill than non-VAP patients following CS. Nevertheless, patients with non-VAP and VAP following CS have similar outcomes. This study suggests that the empiric antibiotic regimen in patients with pneumonia following CS should include at least a broad-spectrum antibiotic targeting non-fermenting Gram-negative bacilli, regardless of the type of pneumonia, and targeting S. aureus in VAP patients.
authors.affiliation: Hôpital Universitaire Félix Guyon, Réanimation Polyvalente, Allée des Topazes, 97400, Saint Denis, France. nicolas.allou@hotmail.fr.|AP-HP, Hôpital Bichat, Département d'Anesthésie-Réanimation, 46 rue Henri Huchard, F-75018, Paris, France. nicolas.allou@hotmail.fr.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Allou
authors.affiliation: Hôpital Universitaire Félix Guyon, Réanimation Polyvalente, Allée des Topazes, 97400, Saint Denis, France. allyn.jer@gmail.com.|AP-HP, Hôpital Bichat, Département d'Anesthésie-Réanimation, 46 rue Henri Huchard, F-75018, Paris, France. allyn.jer@gmail.com.
authors.forename: Jerome
authors.initials: J
authors.lastname: Allyn
authors.affiliation: AP-HP, Hôpital Bichat, Département d'Anesthésie-Réanimation, 46 rue Henri Huchard, F-75018, Paris, France. aurelie.snauwaert@gmail.com.|Univ Paris Diderot, Sorbonne Paris Cité, F-75018, Paris, France. aurelie.snauwaert@gmail.com.
authors.forename: Aurélie
authors.initials: A
authors.lastname: Snauwaert
authors.affiliation: AP-HP, Hôpital Bichat, Département d'Anesthésie-Réanimation, 46 rue Henri Huchard, F-75018, Paris, France. welschcamille@yahoo.fr.|Univ Paris Diderot, Sorbonne Paris Cité, F-75018, Paris, France. welschcamille@yahoo.fr.
authors.forename: Camille
authors.initials: C
authors.lastname: Welsch
authors.affiliation: AP-HP, Hôpital Bichat, Unité d'Hygiène et de lutte Contre les Infections Hospitalières, 46 rue Henri Huchard, F-75018, Paris, France. jean-christophe.lucet@bch.aphp.fr.
authors.forename: Jean Christophe
authors.initials: JC
authors.lastname: Lucet
authors.affiliation: AP-HP, Hôpital Bichat, Département d'Anesthésie-Réanimation, 46 rue Henri Huchard, F-75018, Paris, France. ritakortbaoui@hotmail.com.|Univ Paris Diderot, Sorbonne Paris Cité, F-75018, Paris, France. ritakortbaoui@hotmail.com.
authors.forename: Rita
authors.initials: R
authors.lastname: Kortbaoui
authors.affiliation: AP-HP, Hôpital Bichat, Département d'Anesthésie-Réanimation, 46 rue Henri Huchard, F-75018, Paris, France. mathieu.desmard@bch.aphp.fr.|Univ Paris Diderot, Sorbonne Paris Cité, F-75018, Paris, France. mathieu.desmard@bch.aphp.fr.
authors.forename: Mathieu
authors.initials: M
authors.lastname: Desmard
authors.affiliation: AP-HP, Hôpital Bichat, Département d'Anesthésie-Réanimation, 46 rue Henri Huchard, F-75018, Paris, France. pascal.augustin@bch.aphp.fr.|Univ Paris Diderot, Sorbonne Paris Cité, F-75018, Paris, France. pascal.augustin@bch.aphp.fr.
authors.forename: Pascal
authors.initials: P
authors.lastname: Augustin
authors.affiliation: AP-HP, Hôpital Bichat, Département d'Anesthésie-Réanimation, 46 rue Henri Huchard, F-75018, Paris, France. philippe.montravers@bch.aphp.fr.|Univ Paris Diderot, Sorbonne Paris Cité, F-75018, Paris, France. philippe.montravers@bch.aphp.fr.
authors.forename: Philippe
authors.initials: P
authors.lastname: Montravers
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D006348:Cardiac Surgical Procedures; D016638:Critical Illness; D005260:Female; D006090:Gram-Negative Bacteria / Q000302:isolation & purification; D017052:Hospital Mortality; D006801:Humans; D015994:Incidence; D007362:Intensive Care Units; D008297:Male; D008875:Middle Aged; D010878:Piperacillin / Q000627:therapeutic use; D011014:Pneumonia / Q000188:drug therapy* / Q000209:etiology / Q000382:microbiology; D053717:Pneumonia, Ventilator-Associated / Q000188:drug therapy / Q000382:microbiology; D011183:Postoperative Complications / Q000188:drug therapy* / Q000382:microbiology; D012121:Respiration, Artificial / Q000009:adverse effects*; D012189:Retrospective Studies; D012720:Severity of Illness Index
chemical_list: D000900:Anti-Bacterial Agents; D010878:Piperacillin