Right ventricular dysfunction in septic shock.

Background: Right ventricular dysfunction (RVD) is common in critically ill patients and the presence of this condition affects patients' outcomes. Improving the knowledge background and establishing the incidence of RVD in septic shock patients would render the management more efficacious. This study was performed to evaluate the incidence and outcomes of RVD in septic shock patients.

Material And Method: A single center retrospective observational study was performed in the Medical ICU, Siriraj Hospital, Mahidol University between January 2007 and October 2009. Patients with septic shock in whom pulmonary artery catheter (PAC) was inserted were included in the study.

Results: The PAC was placed in 118 patients during the study period. The patients' mean age was 58.0 +/- 18.5 years and 71 of them (59.3%) were male. The mean body mass index was 25.0 +/- 6.6 Kg/m2 and the mean APACHE II score was 26.1 +/- 7.7. The admission diagnoses were severe sepsis or septic shock (70%), severe pneumonia (38%), acute respiratory distress syndrome (21%). Twenty one patients (17.8%) meet the diagnosis criteria of RVD. The hospital mortality in RVD patients tended to be higher than the non-RVD patients (81.0% vs. 60.8%, p 0.06). Although similar proportions of both group received ventilatory support, the RVD patients had lower tidal volume and had higher peak airway pressure. Also the RVD group had lower PaO2/FiO2 ratio. In addition, the RVD group had lower cardiac output and more frequently underwent renal replacement therapy.

Conclusion: In patients with septic shock, the incidence of RVD is substantial. The significant factors associated with RVD include low tidal volume and high peak airway pressure. Measures to prevent the alteration in lung compliance in septic shock patients may prevent RVD and improve patients' outcomes.