Standardized pharmacological management of delirium after on-pump cardiac surgery reduces ICU stay and ventilation in a retrospective pre-post study

Cardiac surgery patients not only undergo a highly invasive procedure but are at risk for a diversity of postoperative complications. Up to 53% of these patients suffer from postoperative delirium (POD). This severe and common adverse event increases mortality and prolonged mechanical ventilation and extends the intensive care unit stay. The objective of this study was to test the hypothesis that standardized pharmacological management of delirium (SPMD) may reduce the length of stay in the intensive care unit (ICU), duration of postoperative mechanical ventilation, and the incidence of postoperative complications such as pneumonia or bloodstream infections in on-pump cardiac surgery ICU patients. In this retrospective, single-center observational cohort study, 247 patients were examined between May 2018 to June 2020, who underwent on-pump cardiac surgery, suffered from POD, and received pharmacological POD treatment. 125 were treated before and 122 after SPMD implementation in the ICU. The primary endpoint was a composite outcome, including the length of ICU stay, postoperative mechanical ventilation time, and ICU survival rate. The secondary endpoints were complications including postoperative pneumonia and bloodstream infections. Although the ICU survival rate was not significantly different between both groups, the length of ICU stay (control group: 23 ± 27 days; SPMD group: 16 ± 16 days; p = 0.024) and the duration of mechanical ventilation were significantly reduced in the SPMD-cohort (control group: 230 ± 395 h; SPMD group: 128 ± 268 h; p = 0.022). Concordantly, the pneumonic risk was reduced after SPMD introduction (control group: 44.0%; SPMD group: 27.9%; p = 0.012) as well as the incidence for bloodstream infections (control group: 19.2%; SPMD group: 6.6%; p = 0.004). Standardized pharmacological management of postoperative delirium in on-pump cardiac surgery ICU patients reduced the length of ICU stay and duration of mechanical ventilation significantly, leading to a decrease in pneumonic complications and bloodstream infections.