The effect of high frequency oscillatory ventilation combined with tracheal gas insufflation on extravascular lung water in patients with acute respiratory distress syndrome: a randomized, crossover, physiological study.

Purpose: High frequency oscillation combined with tracheal gas insufflation (HFO-TGI) improves oxygenation in patients with Acute Respiratory Distress Syndrome (ARDS). There is limited physiologic data regarding the effects of HFO-TGI on hemodynamics and pulmonary edema during ARDS. The aim of this study was to investigate the effect of HFO-TGI on extravascular lung water (EVLW). Materials and Methods: We conducted a prospective, randomized, crossover study. Consecutive eligible patients with ARDS received sessions of conventional mechanical ventilation (CMV) with recruitment maneuvers (RMs), followed by HFO-TGI with RMs, or vice versa. Each ventilatory technique was administered for 8 hours. The order of administration was randomly assigned. Arterial/central venous blood gas analysis and measurement of hemodynamic parameters and EVLW were performed at baseline and after each 8-hour period using the single-indicator thermodilution technique. Results: Twelve patients received 32 sessions. PaO2/FiO2 and respiratory system compliance were higher (p<0.001 for both), while EVLW indexed to predicted body weight (EVLWI) and oxygenation index were lower (p=0.021 and 0.029, respectively) in HFO-TGI compared with CMV. There was a significant correlation between PaO2/FiO2 improvement and EVLWI drop during HFO-TGI (Rs=-0.452, p= 0.009). Conclusions: HFO-TGI improves gas exchange and lung mechanics in ARDS, and potentially attenuates EVLW accumulation

High-frequency oscillation and tracheal gas insufflation in patients with severe acute respiratory distress syndrome and traumatic brain injury: an interventional physiological study

In acute respiratory distress syndrome (ARDS), combined high-frequency oscillation (HFO) and tracheal gas insufflation (TGI) improves gas exchange compared with conventional mechanical ventilation (CMV). We evaluated the effect of HFO-TGI on PaO2/fractional inspired O2 (FiO2) and PaCO2, systemic hemodynamics, intracranial pressure (ICP), and cerebral perfusion pressure (CPP) in patients with traumatic brain injury (TBI) and concurrent severe ARDS

Dexmedetomidine for paroxysmal sympathetic hyperactivity in a patient with traumatic brain injury: a case report in the intensive care unit

In this case report we describe the course of a patient with severe traumatic brain injury who, upon withdrawal of sedation, presented the characteristic clinical signs of paroxysmal sympathetic hyperactivity and responded to the combination of dexmedetomidine infusion and oral metoprolol. We present the diagnostic and therapeutic rationale that guided our decisions and summarize the current knowledge on the topic

Correlation of Serum and Urine Midazolam Levels with Consciousness Tests after Discontinuation of Sedation in the Intensive Care Unit

Title: Correlation of serum and urine midazolam levels with observed level of consciousness after discontinuation of midazolam sedation in the intensive care unit &nbsp; Marilena Papadaki1, Maria Pratikaki2, Achilleas Giannopoulos1, Theodora Ntaidou1, Eleftheria Mizi1, Marios Kougias1, Georgios Bouboulis1, Aikaterini Sarri1 and Charikleia S Vrettou1 &nbsp; 1 &nbsp;1st Department of Intensive Care, Evangelismos Hospital, University of Athens Medical School, 45-47 Ipsilantou Str., 106 76 Athens, Greece 2 Department of Clinical Biochemistry, Evangelismos Hospital, Athens, Greece &nbsp; Introduction: Continuous infusion of midazolam is related to prolonged activity and delayed awakening in the critically ill. Serum benzodiazepine levels can be helpful in differentiating residual benzodiazepine activity from other causes of impaired level of consciousness (LOC) [1]. Although benzodiazepine levels can also be measured in the urine, the relationship between serum and urine levels with the observed LOC has not been studied in clinical practice. Objectives: To investigate the correlation between serum and urine benzodiazepine levels in the critically ill and their correlation with the observed level of consciousness estimated with the Glasgow Coma Scale (GCS) and the Full Outline of UnResponsiveness Score (FOUR score). Patients and Methods: This prospective observational study involved patients admitted to a 30 bed General Intensive Care Unit, who were intubated and mechanically ventilated, with GCS prior to intubation &gt; 8. Midazolam infusion was discontinued for at least 12 hours before sampling. Serum and urine sampling and clinical evaluation to calculate the GCS and FOUR score were done simultaneously. Gathered data included age, sex, weight and height, reason for admission to intensive care, renal function, daily fluid balance, daily and hourly urine output, liver function, serum proteins, hemoglobin and the application of renal replacement therapy. Serum benzodiazepine measurements were performed on the Integra system (Roche), which is suitable for semiquantitative detection of benzodiazepines in the serum. Urine benzodiazepine levels were measured with the Cobas C501 system, which is suitable for semiquantitative detection of benzodiazepines in human urine. The Scientific and Ethics committee of Evangelismos hospital approved the study protocol. Results: Twenty patients were included in the study, 10 male and 10 female. Reasons for ICU admission were septic shock (n=7), respiratory failure and ARDS (n=7), and acute surgery and trauma (n=6). Patients’ age ranged from 20 to 90 years old (median 66 years) and their weight from 45 to 160 Kg &nbsp;(median 77.5 Kg). The SOFA score ranged from 4 to 15 (median 8). The GCS score from 3 to 14 (median 7) and the FOUR score from 3 to 15 (median 10). Six patients were on continuous veno-venous haemodiafiltration (CVVHD) at sampling time. Serum benzodiazepine levels correlate moderately with the GCS (R =-0.496, p=0.026) and better with the FOUR score (R =-0.685, p=0.001), but did not correlate with measured levels in the urine (R =-0.029 p=0.904), even when patients without AKI were analysed separately (n= 12, R = 0.173, p=0.572). Figure 1 presents the scatter plot of measured urine and serum benzodiazepine levels in our sample. Conclusions: In patients treated in the intensive care unit, after discontinuation of midazolam sedation, the LOC (GCS and FOUR score) correlate significantly with the benzodiazepine levels measured in the serum. Urine benzodiazepine levels do not correlate with serum levels or with the observed LOC and therefore cannot be helpful in the differential diagnosis of drowsiness or coma in this population. References: (1) Rosich Andreu et al. Intensive Care Medicine Experimental 2015, 3(Suppl 1):A330 &nbsp; &nbsp; &nbsp

Mechanical ventilation of patients with acute respiratory distress syndrome using high frequency oscillation combined with tracheal gas insufflation

Mechanical ventilation with High Frequency Oscillation combined with Tracheal Gas Insufflation (HFO-TGI) improves gas exchange and respiratory system mechanics in patients with Acute Respiratory Distress Syndrome (ARDS). Intermittent recruitment with HFO-TGI is also related with improved survival in ARDS patients. The aim of this doctoral research is to investigate the effect of HFO-TGI on the lung’s inflammatory response, the accumulation of pulmonary oedema, and the evaluation of the efficacy and safety of HFO-TGI application in patients with traumatic brain injury (TBI) and concommitant ARDS. This doctoral thesis contains the results of three clinical trials. In the first, randomised, interventional trial we found that patients who received HFO-TGI sessions had increased levels of inflammatory markers in the bronchoalveolar lavage. In the second, cross-over clinical trial, we observed a reduction of extravascular lung water index related with improved oxygenation during the application of HFO-TGI in patients with ARDS. Finally, in a interventional physiological study we showed that intermittent recruitment with HFO-TGI in patients with TBI and ARDS improves gas exchange and respiratory system mechanics, without adversely affecting haemodynamics, and specifically the intracranial pressure and the cerebral perfusion pressure.Ο μηχανικός αερισμός με συνδυασμό ταλαντωτή υψηλής συχνότητας και ενδοτραχειακής εμφύσησης αερίων (HFO-TGI) βελτιώνει την ανταλλαγή των αερίων και την μηχανική του αερισμού σε ασθενείς με σύνδρομο οξείας αναπνευστικής δυσχέρειας (ARDS). Έχει επίσης βρεθεί ότι η διαλείπουσα εφαρμογή συνεδριών HFO-TGI σε ασθενείς με ARDS σχετίζεται και με βελτίωση της επιβίωσης. Σκοπός της παρούσας διδακτορικής έρευνας είναι η μελέτη της της επίδρασης του HFO-TGI στην φλεγμονώδη απάντηση του πνεύμονα, στην εξέλιξη του πνευμονικού οιδήματος, και η εκτίμηση της ασφάλειας και της αποτελεσματικότητας του HFO-TGI σε ασθενείς με ARDS και κρανιοεγκεφαλική κάκωση (ΚΕΚ).Στα πλαίσια αυτής της διδακτορικής έρευνας διενεργήθηκαν τρεις κλινικές δοκιμές. Στην πρώτη διπλή τυχαιοποιημένη παρεμβατική μελέτη βρήκαμε ότι ασθενείς που έλαβαν συνεδρίες HFO-TGI εμφάνισαν αύξηση των δεικτών φλεγμονής στο βρογχοκυψελιδικό έκπλυμα έναντι ασθενών που αερίστηκαν αποκλειστικά με συμβατικό μηχανικό αερισμό. Στην δεύτερη, τυχαιοποιημένη διασταυρούμενη κλινική μελέτη διαπιστώσαμε ότι το HFO-TGI προκαλεί μείωση του δείκτη εξωπνευμονικού ύδατος, η οποία σχετίζεται με τη βελτίωση της οξυγόνωσης σε ασθενείς με ARDS. Τέλος σε παρεμβατική φυσιολογική μελέτη δείξαμε ότι το HFO-TGI όταν εφαρμόζεται σε ασθενείς με ΚΕΚ και ARDS επιδρά ευνοϊκά στην ανταλλαγή των αερίων και στη μηχανική του αερισμού χωρίς δυσμενείς επιπτώσεις στις αιμοδυναμικές παραμέτρους και ιδιαίτερα στην ενδοκράνιο πίεση και στην πίεση εγκεφαλικής άδρευσης

Second- and Third-Tier Therapies for Severe Traumatic Brain Injury

Intracranial hypertension is a common finding in patients with severe traumatic brain injury. These patients need treatment in the intensive care unit, where intracranial pressure monitoring and, whenever possible, multimodal neuromonitoring can be applied. A three-tier approach is suggested in current recommendations, in which higher-tier therapies have more significant side effects. In this review, we explain the rationale for this approach, and analyze the benefits and risks of each therapeutic modality. Finally, we discuss, based on the most recent recommendations, how this approach can be adapted in low- and middle-income countries, where available resources are limited

COVID-19-Related ARDS: Key Mechanistic Features and Treatments

Acute respiratory distress syndrome (ARDS) is a heterogeneous syndrome historically characterized by the presence of severe hypoxemia, high-permeability pulmonary edema manifesting as diffuse alveolar infiltrate on chest radiograph, and reduced compliance of the integrated respiratory system as a result of widespread compressive atelectasis and fluid-filled alveoli. Coronavirus disease 19 (COVID-19)-associated ARDS (C-ARDS) is a novel etiology caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that may present with distinct clinical features as a result of the viral pathobiology unique to SARS-CoV-2. In particular, severe injury to the pulmonary vascular endothelium, accompanied by the presence of diffuse microthrombi in the pulmonary microcirculation, can lead to a clinical presentation in which the severity of impaired gas exchange becomes uncoupled from lung capacity and respiratory mechanics. The purpose of this review is to highlight the key mechanistic features of C-ARDS and to discuss the implications these features have on its treatment. In some patients with C-ARDS, rigid adherence to guidelines derived from clinical trials in the pre-COVID era may not be appropriate