Effectiveness and cost of selective decontamination of the digestive tract in critically ill intubated patients. A randomized, double-blind, placebo-controlled, multicenter trial.

We evaluated the effect of selective decontamination of the digestive tract (SDD) on the incidence of ventilator-associated pneumonia (VAP) and its associated morbidity and cost in a mixed population of intubated patients. Two hundred seventy-one consecutive patients admitted to the intensive care units (ICUs) of five teaching hospitals and who had an expected need for intubation exceeding 48 h were enrolled and received topical antibiotics or placebo. Uninfected patients additionally received ceftriaxone or placebo for 3 d. VAP occurred in 11.4% of SDD-treated and 29.3% of control-group patients (p < 0.001; 95% confidence interval [CI]: 7.8 to 27.9). The incidence of nonrespiratory infections in the two groups was 19.1% and 30.7%, respectively (p = 0.04; 95% CI: 0.7 to 22.7). Among survivors, the median length of ICU stay was 11 d (interquartile range: 7 to 21.5 d) for the SDD-treated group and 16. 5 d (10 to 30 d) for the control group (p = 0.006). Mean cost per survivor was $11,926 for treated and $16,296 for control-group patients. Mortality was 38.9% and 47.1%, respectively (p = 0.57). In decontaminated patients, the prevalence of gram-negative bacilli fell within 7 d from 47.4% to 13.0% (p < 0.001), whereas colonization with resistant gram-positive strains was higher (p < 0. 05) than in the placebo group. In a mixed population of intubated patients, SDD was associated with a significant reduction of morbidity at a reduced cost. Our findings support the use of SDD in this high-risk group.

Oxygen delivery-dependent oxygen consumption in acute respiratory failure.

OBJECTIVE: To investigate whether oxygen consumption (VO2) is dependent on oxygen delivery (DO2) in adult respiratory distress syndrome (ARDS) and non-ARDS acute respiratory failure. DESIGN: Intervention study of a consecutive sample of patients admitted to the ICU with the diagnosis of acute respiratory failure. SETTING: Tertiary care center. PATIENTS: Thirteen consecutive patients with a diagnosis of ARDS and 11 with a diagnosis of respiratory failure not due to ARDS. Patients were monitored with an oximetric pulmonary artery catheter and mechanically ventilated. INTERVENTIONS: DO2 was decreased by the application of positive end-expiratory pressure (PEEP) (20 cm H2O), and subsequently increased by an iv infusion of dobutamine (10 micrograms/kg.min). RESULTS: After the application of PEEP, DO2 decreased significantly in both groups. However, VO2 decreased significantly (p less than .01) only in the ARDS group. When dobutamine was infused, DO2 increased significantly (p less than .01) in both groups, but VO2 increased only in ARDS patients. DO2 correlated significantly with VO2 both in ARDS (r2 = .81, p less than .01) and in non-ARDS (r2 = .38, p less than .05) patients. The correlation coefficient was significantly higher for ARDS than for non-ARDS patients. Comparing the slopes of the regression lines, a stronger dependency of VO2 on DO2 was found in ARDS than in non-ARDS respiratory failure (p less than .001). The oxygen extraction ratio correlated with DO2 in non-ARDS patients (r2 = .49, p less than .05), but not in ARDS patients. CONCLUSIONS: VO2 is dependent on DO2 over a wide range of DO2 values in acute respiratory failure. This dependency phenomenon is much stronger in ARDS than in respiratory failure due to other causes. Due to the abnormal dependency of VO2 on DO2, changes in the oxygenation status may not be reflected by changes in mixed venous oxygen saturation in ARDS.

[Changes in tissue oxygen extraction in patients with acute respiratory insufficiency]. / Alteraciones en la extracción hística de oxígeno en pacientes con insuficiencia respiratoria aguda.

We analyzed the tissue oxygen extraction in 25 patients with acute respiratory failure. Fourteen met the clinical criteria for the adult respiratory distress syndrome (ARDS). The 11 remaining patients had acute respiratory failure with causes different from ARDS. In all cases the changes in the oxygen extraction ratio (O2ER) and in the oxygen consumption (VO2) were evaluated after changing oxygen availability (O2A) with positive end-expiratory pressure (PEEP) and dobutamine infusion. The patients with ARDS showed a change in VO2 parallel to O2A changes, with a significant correlation (r = 0.85); however, no changes were found in O2ER (r = 18). In the patients without ARDS, the changes in O2A did not modify the VO2 (r = 0.02) but there was a significant inverse relationship between DO2 and O2ER (r = -0.70). These findings suggest an abnormal regulation of tissue oxygen extraction and an abnormal dependence of VO2 on O2A in cases with ARDS. Dobutamine therapy, in addition to inotropic effects, could improve a situation of hidden hypoxia, as it is a vasodilator that might act on microvasculature.

[Pulmonary microvascular cytology in critical patients]. / Citología microvascular pulmonar en el enfermo crítico.

Cytology in blood drawn through a wedged Swan-Ganz catheter appears as a sensitive method for the diagnosis of carcinomatous lymphangitis in patients in whom transbronchial biopsy is considered dangerous or who refuse to undergo the latter procedure. However, its usefulness has not been assessed in critical patients with acute respiratory failure of unknown etiology in whom malignant disease is suspected. We report our experience in two patients admitted to the Intensive Care Unit with acute respiratory failure of unknown etiology: they were a female with breast carcinoma and a male with lymphoma in whom the cytological study of pulmonary capillary blood disclosed malignant cells. The clinical evaluation and the subsequent histological studies confirmed the pulmonary involvement by malignant disease in both cases.

Alveolar proteinosis and nocardiosis: a patient treated by bronchopulmonary lavage.

Alveolar proteinosis is a relatively rare disease of unclear pathogenesis associated with opportunistic-infections. Although nocardiosis is the most frequent one, only 22 cases have been reported previously and are reviewed here. We present a patient with alveolar proteinosis with nocardiosis treated as an emergency with bilateral bronchopulmonary lavage and antibiotics. No previous cases of this association have been successfully managed in this way.

[Rupture of simple renal cyst after minimal renal injury]. / Rotura de quiste renal simple tras traumatismo renal mínimo.

A case is presented of minimum renal trauma, leading to a retroperitoneal hematoma as a consequence of a simple renal cyst rupture as well as an artery contained therein. The etiopathogenicity of this phenomenon is commented. The different clinical manifestations of renal trauma are highlighted, as well as the suspicion of previous renal pathology when a large renal lesion is found secondary to minimum renal trauma. The approach of the renal pediculum must be the first step in the surgical treatment of renal trauma.