In Vivo Measurement of Tidal Volume During Non-invasive Respiratory Support by Continuous-Flow Helmet CPAP.

Recently, the interest in the Helmet interface during non-invasive respiratory support (NIRS) has increased due to the COVID-19 pandemic. During NIRS, positive end-expiratory pressure (PEEP) can be given as continuous positive airway pressure (CPAP), which maintains a positive airway pressure throughout the whole respiratory cycle with Helmet as an interface (H-CPAP). The main disadvantage of the H-CPAP is the inability to measure tidal volume (VT). Opto-electronic plethysmography (OEP) is a non-invasive technique that is not sensitive to gas compression/expansion inside the helmet. OEP acquisitions were performed on 28 healthy volunteers (14 females and 14 males) at baseline and during Helmet CPAP. The effect of posture (semi-recumbent vs. prone), flow (50 vs. 60 L/min), and PEEP (0 vs. 5 vs. 10 cmH2O) on the ventilatory and thoracic-abdominal pattern and the operational volumes were investigated. Prone position limited vital capacity, abdominal expansion and chest wall recruitment. A constant flow of 60 L/min reduced the need for the subject to ventilate while having a slight recruitment effect (100 mL) in the semi-recumbent position. A progressive increasing recruitment was found with higher PEEP but limited by the prone position. It is possible to accurately measure tidal volume during H-CPAP to deliver non-invasive ventilatory support using opto-electronic plethysmography during different clinical settings.

Role of noninvasive ventilation in elderly patients with hypercapnic respiratory failure.

The effectiveness of non-invasive ventilation (NIV) in treating patients with acute respiratory failure (ARF) is showed by its ability to diminish the recurrence to endotracheal intubation (ETI), the occurrence of ETI-associated lung infections as well as related mortality. A specific issue is the outcome of NIV in patients referring to Emergency Department for ARF who receive a do-not-intubate (DNI) order because of too critical conditions or advanced age. Recent data show that elderly patients (mean age 81 years) with ARF who have a DNI order can be successfully treated by NIV, as demonstrated by a survival rate of 83%. The positive outcome was confirmed by a subsequent 3-year observation, that demonstrated an overall survival rate of 54%. These findings clearly suggest to treat by NIV elderly patients also in presence of a DNI order.

[Intravenous nitroglycerin infusion suppresses exercise-induced arrhythmia in patients with ischemic cardiopathy: indications for chronic treatment ]. / L'infusione endovenosa di nitroglicerina sopprime le aritmie indotte da slorzo in pazienti con cardiopatia ischemica: indicazioni per il trattamento cronico.

In patients with ischemic heart disease and arrhythmias, selection of antiarrhythmic treatment is often difficult as it is hard to separate "primary" from ischemic arrhythmias. We studied 20 patients with ischemic heart disease, who developed ventricular arrhythmias consistently during exercise test. Exercise test was performed twice during infusion of placebo and then during intravenous administration of nitroglycerin, titrated to reduce systolic blood pressure by 10 mmHg. Exercise duration was 7.8 +/- 1.7 and 7.9 +/- 1.5 min, in the 2 placebo tests (NS). Angina developed in 5 patients and ischemic ST changes in 10. With nitroglycerin exercise duration increased to 8.4 +/- 20 min (p less than 0.05), diagnostic ST segment depression was observed in 2 patients and only 1 had angina. In all 20 patients, ventricular arrhythmias were consistently present during both tests on placebo, that were markedly reduced by nitroglycerin. In fact, ventricular ectopic beats were 455 (mean 35.8 +/- 16.8) and 418 (mean 34.4 +/- 11.1) in the 2 exercise tests with placebo, and 11 during nitroglycerin infusion (mean 0.6 +/- 0.1; p less than 0.001). Couplets were 28 and 29 during placebo (NS) and 0 during nitroglycerin (p less than 0.001). Ventricular tachycardia was present in 6 and 8 patients during placebo but in none during nitroglycerin (p less than 0.001). Reduction of exercise-induced arrhythmias was maintained during chronic treatment with oral vasodilators. Prevention of exercise-related arrhythmias by nitroglycerin infusion appears a good indicator of their ischemic origin and may provide valuable information for long-term profilaxis with oral vasodilators, then avoiding the use of antiarrhythmic agents and their potential side effects.

Pharmacokinetic profile of cefotetan in different clinical conditions.

The pharmacokinetic profile of cefotetan was studied in a group of hospitalized patients. The absorption of the molecule (after a single dose of 2 g/i.m.) was good and the drug was found to diffuse satisfactorily in the lungs, prostatic tissue, kidney and in the female genitalia.

Comparison between sulbenicillin and piperacillin levels in serum and in bronchial secretions--a pharmacokinetic study.

In order to assess pharmacokinetic differences between sulbenicillin (S) and piperacillin (P), two penicillin derivatives, 24 in-patients, 12 males and 12 females mean age 59.4 years, suffering from recurrent bronchial infections were enrolled. Patients were randomly allocated to S (12 patients) and to P (12 patients) and were given 2 g i.m. every 12 h of the awarded antibiotic, for a 7-day period. At the first and 7th day blood samples (0.25, 0.5, 1, 2, 4, 6, 8 and 12 h after dosing) as well as sputum samples (1, 2, 4, 8, 12 h after dosing) and urine samples (3, 6, 9 and 12 h after dosing) were collected, and the levels of S or P were determined by bacillus subtilis test. The pharmacokinetic analysis was performed by a standard program. On day 1 and 7 the mean peak serum concentration occurred at the first hour for S (39.9 +/- 5.2; 40.9 +/- 5.1 mcg/ml, respectively) and for P (32.2 +/- 5.4; 33.1 +/- 5.4 mcg/ml, respectively). Serum AUC0-12 and AUC0-00 (mg/l.h) levels of S were significantly higher (p less than 0.01 or less) than those of P on day 1 and 7. Similarly MRT (8 h) and Cmax (mg/l) where higher but only on day 7. Sputum AUC0-12 (mg/l.h) level of S was significantly higher (p less than 0.05) than that of P on day 1 and 7. In conclusion serum and sputum S appear to have a different pharmacokinetic profile in respect to P. However, when compared to the AUC, both drugs reach antibacterial levels.