Pathophysiological profile of non-ventilated lung injury in healthy female pigs undergoing mechanical ventilation.

BACKGROUND: Lung regions excluded from mechanical insufflation are traditionally assumed to be spared from ventilation-associated lung injury. However, preliminary data showed activation of potential mechanisms of injury within these non-ventilated regions (e.g., hypoperfusion, inflammation). METHODS: In the present study, we hypothesized that non-ventilated lung injury (NVLI) may develop within 24 h of unilateral mechanical ventilation in previously healthy pigs, and we performed extended pathophysiological measures to profile NVLI. We included two experimental groups undergoing exclusion of the left lung from the ventilation with two different tidal volumes (15 vs 7.5 ml/kg) and a control group on bilateral ventilation. Pathophysiological alteration including lung collapse, changes in lung perfusion, lung stress and inflammation were measured. Lung injury was quantified by histological score. RESULTS: Histological injury score of the non-ventilated lung is significantly higher than normally expanded lung from control animals. The histological score showed lower intermediate values (but still higher than controls) when the tidal volume distending the ventilated lung was reduced by 50%. Main pathophysiological alterations associated with NVLI were: extensive lung collapse; very low pulmonary perfusion; high inspiratory airways pressure; and higher concentrations of acute-phase inflammatory cytokines IL-6, IL-1ß and TNF-α and of Angiopoietin-2 (a marker of endothelial activation) in the broncho-alveolar lavage. Only the last two alterations were mitigated by reducing tidal volume, potentially explaining partial protection. CONCLUSIONS: Non-ventilated lung injury develops within 24 h of controlled mechanical ventilation due to multiple pathophysiological alterations, which are only partially prevented by low tidal volume.

Respiratory failure that occurs in cases of atelectasis, pneumonia and acute hypoxemic respiratory failure a machine called a mechanical ventilator is used to move air in and out of the patient's lungs. We know that the use of a mechanical ventilator can induce lung injury, but complete exclusion from ventilation might not be safe. Using pig lungs to mimic the patient's lungs, we evaluated the use of a ventilator against non-use. We find that the lungs sustained injury regardless of ventilator use. The non-ventilated lung injury consisted of collapse (lack of expansion), low amount of blood flow, high ventilation pressure and inflammatory response. Physicians should be aware that also the regions of the lung not receiving ventilation are at risk of injury.

[Feasibility and efficacy of home monitoring for patients with suspected or confirmed COVID-19.] / Fattibilità ed efficacia di un modello di monitoraggio domiciliare avanzato dei pazienti affetti da CoViD-19 o sospetti.

INTRODUCTION: The MonCOVID study aimed to assess the feasibility of early home management and monitoring of patients with suspected or confirmed CoViD-19, and to evaluate if this would ensure a rapid and adequate transfer to hospital care. METHODS: This pilot, open-label, single-arm study included adult symptomatic patients with suspected or confirmed CoViD-19 for whom the general practitioner or other carer had decided not to proceed to hospitalization. Participants were monitored daily at home, by measuring the pulse oximetry (SpO2) at rest and after a rapid walking test. The study assessed feasibility outcomes (at least 80% of patients recommended to be sent to the competent emergency room actually transferred within 24 hours from reporting) and efficacy (SpO2 at emergency room admission). Patients with SpO2 values below 90% (86% if affected by chronic pulmonary diseases) at rest or with a decrease in SpO2 of five percentage points after a rapid walking test were recommended for hospital care. RESULTS: Thirty-seven participants reported by the local health unit of Alessandria and the Metropolitan City of Turin were included in the study. Enrollment, initially planned for two months to reach a target of 340, was interrupted early due to the drastic reduction in the number of cases. On average, each participant was monitored for 8.2 (median 6.0) days, for a total of 302 visits. The participants showed milder symptoms than those observed in the first phase of the epidemic, at least in terms of pulmonary impairment. No patient had a decrease in SpO2 of 5 percentage points or greater and only one patient required hospitalization due to a worsening of the disease. DISCUSSION: The cases collected were not sufficient to demonstrate or refute the hypothesis of the monitoring test effectiveness. However, the study showed the feasibility of such a program, and raised some elements of interest regarding hospital territory integration, the need to develop tools to support home care and the variability of the clinical manifestations of the CoViD-19 disease.

Integration of ultrasound in medical School: Effects on Physical Examination Skills of Undergraduates.

INTRODUCTION: Ultrasound (US) imaging has rapidly increased its application in almost every medical field. Many universities worldwide provide teaching of US for undergraduates in their curricula. Emerging evidence is supporting the use of ultrasonography to improve also non-US skills and knowledge of medical students. OBJECTIVES: The purpose of this review is to understand if the integration of US lessons into medical students' curriculum improves their learning of physical examination and enhances their skills when performing it. METHODS: We performed a systematic review of literature by searching three electronic medical databases. We included studies of any level of evidence published in peer-reviewed journals. Evaluated data were extracted using the PICO framework and critically analyzed. PRISMA guidelines were applied; we excluded all the articles evaluated with serious risk of bias and/or low methodological quality. RESULTS: We included 15 articles, accounting for more than 1643 medical students involved from five different countries and 14 various academical institutions. Eight out of nine studies (88.9%) reported an improvement of practical physical examination scores by students exposed to ultrasound lectures. Eleven out of eleven studies (100%), which administered self-assessment questionnaires, reported strong agreement among students that ultrasound lectures helped them learning and understanding the physical exam and improved their confidence and skills. CONCLUSIONS: Increasing evidence shows that incorporating ultrasound in medical students' curriculum might improve their ability and confidence when learning and performing a physical exam. This significant tendency needs to be corroborated at a deeper level by further studies.

Correlation analysis between echocardiographic flow pattern and N-terminal-pro-brain natriuretic peptide for early targeted treatment of patent ductus arteriosus.

OBJECTIVE: Echocardiographic flow patterns of patent ductus arteriosus (PDA) are useful to predict the development of hemodynamically significant ductus in premature infants. N-terminal pro-brain natriuretic peptide (NT-proBNP) concentrations seem to be useful to detect PDA. We investigated how NT-proBNP levels change on the basis of different flow patterns during the first day of life, and whether NT-proBNP might represent a reliable decision tool in PDA management. METHODS: Neonates with gestational age <32 weeks were assessed prospectively, using paired Doppler-echocardiographic evaluation and NT-proBNP values, at T0 (6-24 h of life), and daily until ductal closure. RESULTS: At T0, NT-proBNP concentrations of 41 neonates correlated to the kind of pattern (p = 0.018) with the highest values in neonates with pulsatile or growing patterns. A value <9854 pg/ml identified neonates with spontaneous closure (sensitivity 71.8%, specificity 100%). Overall, 32 infants needed treatment. Pre-treatment NT-proBNP values increased compared to those at T0, significantly in neonates with growing pattern at T0 (p = 0.001). After treatment, NT-proBNP concentrations decreased compared to pre-treatment values (p = 0.0024), more markedly in the responders than in the non-responders (p = 0.042). CONCLUSIONS: NT-proBNP concentrations at T0 show a good agreement with different flow patterns and represent a useful tool to identify neonates at risk of developing hemodynamically significant PDA.

Peripheral nerve blockade and neonatal limb ischemia: our experience and literature review.

Considering the high frequency of bleeding complications following fibrinolytic treatment in neonates, peripheral nerve blockade (PNB) has been proposed alone or in association with lower doses of tissue plasminogen activator, as a possible new therapeutic approach in the management of neonatal limb ischemia (LI) secondary to vasospasm and/or thrombosis. The present article provides a review of the current knowledge about the topic, in order to evaluate the efficacy and safety of this therapeutic approach. According to the few case reports documented in literature and to our experience, PNB could be considered as valid procedure for the treatment of LI, especially during neonatal period, when the risk of serious bleeding associated with fibrinolytic or anticoagulant therapy is higher. Peripheral nerve blockade resulted in a safe and effective procedure for the treatment of neonatal vascular spasm and thrombosis.

Use of a combined SpO2/PtcCO2 sensor in the delivery room.

Arterial oxygen saturation (SaO(2)) and partial arterial pressure of carbon dioxide (PaCO(2)) are important respiratory parameters in critically ill neonates. A sensor combining a pulse oximeter with the Stow-Severinghaus electrode, required for the measurement of peripheral oxygen saturation (SpO(2)) and transcutaneous partial pressure of carbon dioxide (PtcCO(2)), respectively, has been recently used in neonatal clinical practice (TOSCA(500Ò)Radiometer). We evaluated TOSCA usability and reliability in the delivery room (DR), throughout three different periods, on term, late-preterm, and preterm neonates. During the first period (period A), 30 healthy term neonates were simultaneously monitored with both TOSCA and a MASIMO pulse oximeter. During the second period (period B), 10 healthy late-preterm neonates were monitored with both TOSCA and a transcutaneous device measuring PtcCO(2) (TINA(Ò) TCM3, Radiometer). During the third period (period C), 15 preterm neonates were monitored with TOSCA and MASIMO after birth, during stabilization, and during transport to the neonatal intensive care unit (NICU). Blood gas analyses were performed to compare transcutaneous and blood gas values. TOSCA resulted easily and safely usable in the DR, allowing reliable noninvasive SaO(2) estimation. Since PtcCO(2) measurements with TOSCA required at least 10 min to be stable and reliable, this parameter was not useful during the early resuscitation immediately after birth. Moreover, PtcCO(2) levels were less precise if compared to the conventional transcutaneous monitoring. However, PtcCO(2) measurement by TOSCA was useful as trend-monitoring after stabilization and during transport to NICU.