Showing papers by "Massimo Antonelli published in 1995"

Paralysis has no effect on chest wall and respiratory system mechanics of mechanically ventilated, sedated patients

Abstract: To evaluate the separate effects of sedation and paralysis on chest wall and respiratory system mechanics of mechanically ventilated, critically ill patients.Setting: ICU of the University “La Sapienza” Hospital, Rome. 13 critically ill patients were enrolled in this study. All were affected by disease involving both lungs and chest wall mechanics (ARDS in 4 patients, closed chest trauma without flail chest in 4 patients, cardiogenic pulmonary oedema with fluidic overload in 5 patients). Respiratory system and chest wall mechanics were evaluated during constant flow controlled mechanical ventilation in basal conditions (i. e. with the patients under apnoic sedation) and after paralysis with pancuronium bromide. In details, we simultaneously recorded airflow, tracheal pressure, esophageal pressure and tidal volume; with the end-inspiratory and end-expiratory airway occlusion technique we could evaluate respiratory system and chest wall elastance and resistances. Lung mechanics was evaluated by subtracting chest wall from respiratory system data. All data obtained in basal conditions (with the patients sedated with thiopental or propofol) and after muscle paralysis were compared using the Student'st test for paired data. The administration of pancuronium bromide to sedated patients induced a complete muscle paralysis without producing significant modification both to the viscoelastic and to the resistive parameters of chest wall and respiratory system. This study demonstrates the lack of additive effects of muscle paralysis in mechanically ventilated, sedated patients. Also in view of the possible side effects of muscle paralysis, our results question the usefulness of generalyzed administration of neuromuscular blocking drugs in mechanically ventilated patients.

Construction and performance of the lead-scintillating fiber calorimeter prototypes for the KLOE detector

Abstract: The KLOE detector is designed primarily for the study of direct CP violation in K0 decays. The electromagnetic calorimeter, EmC, is a most demanding element of the detector. Two prototypes of the EmC (one for the barrel and one for the end-cap region) have been built at Frascati and tested at PSI (Switzerland) using beams of electrons, muons and pions of 40 to 290 MeV/c momentum, and at the Frascati LADON facility using photons of 20 to 80 MeV. We observe excellent linearity from 20 to 290 MeV. The energy resolution is σ(E)/E ∼ 4.4% / ”E(GeV) and the time resolution is ∼ 34 ps/”E(GeV). We found little dependence on incidence angle and entry position. We also determined that some πμ identification is possible.

High IL-6 serum levels are associated with septic shock and mortality in septic patients with severe leukopenia due to hematological malignancies.

Abstract: The serum levels of immunoreactive interleukin-6 (IL-6) and tumor necrosis factor (TNF) were analyzed in 14 leukopenic patients with documented sepsis, at 60 min (TO), 24h (Tl), 48h (T2) and 1 week (T3) after the onset of sepsis syndrome. Sera from 10 leukopenic patients without sepsis (controls) were also tested. All septic patients had high IL-6 levels at TO. These levels persisted only in the seven patients who died of septic shock, presenting a 30-fold increase (p < 0.001) as compared to the survivors and the controls. At T3, 7 survivors had recovered from sepsis and showed low IL-6 serum levels. The TNF serum concentration always < 30 pg/ml in both the subjects and in the controls. The C-reactive protein (CRP) and clinical parameters appeared to be less specifically associated with shock and mortality than IL-6.

Bacteremia, Pneumonia, and Acute Renal Failure in Trauma Patients

Abstract: Trauma constitutes one of the main cause of death for the USA population in the first decades of life and the third cause of death in all age groups after cancer and atherosclerosis. Mortality from trauma has a multimodal distribution, with a first peak (few minutes after the traumatic event) produced by injuries of intrinsic lethal nature. The second peak (minutes to hours after the traumatic event) is produced by injuries of potentially lethal nature (neurologic injury or hemorrhage). Finally, the third peak (days or weeks) is due to sepsis and multiple organ failure (MOF) [1].