Volumen sanguíneo intratorácico versus presión arterial de oclusión pulmonar como estimadores de precarga cardíaca en pacientes críticos / Intrathoracic blood volume versus pulmonary artery occlusion pressure as estimators of cardiac preload in critically ill patients

Background:Monitoring of cardiac preload by determination of pulmonary artery occlusion pressure (PAOP) has been traditionally used to guide fluid therapy to optimize cardiac output (CO). Since factors such as intrathoracic pressure and ventricular compliance may modify PAOP, volumetric estimators of preload have been developed. The PiCCO system is able to measure CO and intrathoracic blood volume (ITBV) by transpulmonary thermodilution. Aim: To compare a volumetric (ITBV) versus a pressure (PAOP) determination to accurately estimate cardiac preload in severely ill patients. Patients and Methods: From June 2001 to October 2003, 22 mechanically ventilated patients with hemodynamic instability underwent hemodynamic monitoring with pulmonary artery catheter (PAC) and PiCCO system. ITBV index (ITBVI), PAOP and CI were measured simultaneously by both methods. One hundred thirty eight deltas (D) were obtained from the difference of ITBVI, PAOP, CI-PAC and CI-PiCCO between 6-12 am and 6-12 pm. Linear regression analysis of DITBVI versus Ð CI-PiCCO and Ð PAOP versus DCI-PAC were made. Results: Mean age of patients was 60.8 ± 19.4 years. APACHE II was 23.9 ± 7. Fifteen patients met criteria for acute respiratory distress syndrome (ARDS). Delta ITBVI significantly correlated with DCI-PiCCO (r=0.54; 95% confidence interval = 0.41-0.65; p <0.01). There was no correlation between DPAOP and Ð CI-PAC. Conclusion: ITBVI correlated better with CI than PAOP, and therefore it seems to be a more accurate estimator of preload in unstable, mechanically ventilated patients.

Enfermedades pulmonares en pacientes infectados con VIH hospitalizados en el Instituto Nacional del Tórax / Lung diseases among HIV infected patients admitted to the \"Instituto Nacional del Torax\" in Santiago, Chile

Background: Pulmonary diseases are common among HIV infected patients. The prevalence of the different diseases varies greatly. Aim: To identify the different pulmonary diseases that affect a Chilean population of HIV infected patients and to identify factors associated with in hospital mortality. Material and methods: Retrospective review of the clinical records of all HIV infected patients with lung diseases discharged from our institution during a period of 3.5 years. Collection of demographic and biomedical data. Results: One hundred seventy one patients (aged 35.7 years, 86% men) had 236 episodes of lung diseases. Only 13.5% of the patients were receiving antiretroviral therapy and 18% were on pneumocystis prophylaxis. Infectious diseases accounted for 87% of the discharges, neoplasm for 5.1%. Pneumocystis jirovecii infection was responsible for 37.7% of the episodes, community acquired pneumonia was seen in 24.1% and mycobacterial diseases in 14.4%. Two or more conditions were present in 13.6%. Death during hospital stay occurred in 19.5%. Multivariate analysis identified pneumothorax as the only significant independent predictor of in-hospital mortality in patients with pneumocystis pneumonia, while nosocomial pneumonia was the only predictor of death among patients with non-pneumocystis pulmonary diseases. Conclusions: Infectious diseases were the main cause of hospitalization among Chilean HIV infected patients. Mortality among these patients remains high. Appropriate antiretroviral therapy and prophylaxis may alter pulmonary disease prevalence in the future. Every effort should be made to avoid the development of pneumothorax and nosocomial pneumonia.