Pendelluft, the movement of gas within different lung regions, is present in animal models of assisted mechanical ventilation and associated with lung overstretching. Due to rebreathing of CO2 as compared to fresh gas, pendelluft might reduce ventilatory efficiency possibly exacerbating patient’s respiratory workload during weaning. Our aim was to measure pendelluft by electrical impedance tomography (EIT) in patients who failed a spontaneous breathing trial (SBT). This is an observational study conducted in a general intensive care unit of a tertiary-level teaching hospital. EIT signal was recorded in 20 patients while pressure support (PS) ventilation was progressively reduced from clinical level (baseline) to 2 cmH2O, as in an SBT; four ventral-to-dorsal lung regions of interest were identified for pendelluft measurement. A regional gas movement (> 6 mL) occurring in a direction opposite to the global EIT signal was considered diagnostic for high pendelluft. Eight patients out of 20 (40%) were classified as high-pendelluft; baseline clinical characteristics did not differ between high- and low-pendelluft patients. At PS reduction, pendelluft and EtCO2 increased more in the high-pendelluft group (p < .001 and .011, respectively). The volume of gas subject to pendelluft moved almost completely from the ventral towards the dorsal lung regions, while the opposite movement was minimal (16.3 [10:32.8] vs. 0 [0:1.8] mL, p = .001). In a subgroup of patients, increased pendelluft volumes positively correlated with markers of respiratory distress such as increased respiratory rate, p0.1, and EtCO2. Occult pendelluft can be measured by EIT, and is frequently present in patients failing an SBT. When present, pendelluft increases with the reduction of ventilator support and is associated with increased EtCO2, suggesting a reduction of the ability to eliminate CO2.

Opioids are extensively used in patients with cancer pain; despite their efficacy, several patients can experience ineffective analgesia and/or side effects. Pharmacogenetics is a new approach to drug prescription based on the “personalized-medicine” concept, i.e., the ability of tailoring treatments to each individual’s genetic/genomic profile. Pharmacogenetics aims to identify specific genetic variants that influence pharmacokinetics and pharmacodynamics of drugs, better determining their effectiveness/safety profile. Opioid response is a complex scenario, but some gene variants have shown a correlation with pain sensitivity, as well as with opioid metabolism and clinical efficacy/adverse events. Although questions remain unanswered, some of these gene variants may already be used to identify specific patients’ phenotypes that are more prone to experience better clinical response (i.e., better analgesia and/or less adverse events). Once adopted, this approach to opioid prescription may improve a patient’s outcome. This review summarizes the available data on genetic variants and opioid response: we will focus on basic pharmacogenetic and its impact in the clinical scenario discussing how they may lead to more appropriate opioid prescription in cancer patients.

BACKGROUND: Standard indications for endotracheal suctioning are often based on clinical judgment on the deterioration of the patient's condition, and/or routine suctioning. TBA Care is a secretion detector that analyses airway sounds and indicates the need for suctioning. OBJECTIVE: To determine the efficacy of TBA Care in detecting retained secretions, compared to standard indications. METHODS: We conducted a prospective randomized trial with 72 general intensive care unit patients randomized at intubation into 2 groups, differing only in suctioning indications. The control group indications were at least 3 scheduled suctionings per day or were clinically driven. The secretion-detector group indications were device signal or clinically driven. At each suctioning session we recorded the indication for suctioning and the amount of secretions removed. Patients were followed until intensive care unit discharge or extubation. Diagnosis of ventilator-associated pneumonia was confirmed via microbiological analysis of suctioned secretions. RESULTS: We analyzed 1,705 suctionings in the control group and 1,354 in the secretion-detector group. The secretion-detector group had fewer suctionings per day (3.9 ± 2.3 vs 4.8 ± 1.2, P = .002) and a lower rate of unnecessary suctionings (4% vs 12%, P < .001). In the secretion-detector group, 97% of the suctionings were performed following the signal from the TBA Care device. In the control group, clinical deterioration (65%) was the most frequent indication for suctioning. The incidence of ventilator-associated pneumonia was similar in the groups. CONCLUSIONS: TBA Care seems to give valid and timely indications for suctioning, anticipating clinical deterioration due to secretion retention and reducing unnecessary suctionings. (ClinicalTrials.gov registration NCT00932776.)