Assessing inspiratory drive and effort in critically ill patients at the bedside.

Unlabelled: Monitoring inspiratory drive and effort may aid proper selection and setting of respiratory support in patients with acute respiratory failure (ARF), whether they are intubated or not. Although diaphragmatic electrical activity (EAdi) and esophageal manometry can be considered the reference methods for assessing respiratory drive and inspiratory effort, respectively, various alternative techniques exist, each with distinct advantages and limitations. This narrative review provides a comprehensive overview of bedside methods to assess respiratory drive and effort, with a primary focus on patients with ARF.

Noninvasive respiratory supports in ICU.

Background: Noninvasive respiratory supports are routinely applied in critically ill patients with acute respiratory failure to avoid intubation and invasive mechanical ventilation, thereby reducing the risk of related complications, and to facilitate successful weaning from mechanical ventilation after extubation. They are also applied during the intubation procedure for preoxygenation with the aim of enhancing oxygenation and ensuring the safety of the procedure.

Main Body: High-flow nasal oxygen decreases airway dead space, provides a stable concentration of inspired oxygen, generates low level of flow-dependent positive airway pressure, and optimizes comfort.

High-Flow Nasal Oxygen versus Mechanical Ventilation Through a Laryngeal Mask During General Anesthesia Without Muscle Paralysis: A Randomized Clinical Trial.

Background: Apneic oxygenation with high-flow nasal oxygen is a novel intraoperative respiratory support strategy for patients undergoing general anesthesia, but data about its clinical effects are scarce. We conducted a randomized trial to assess whether high-flow nasal oxygen is noninferior to mechanical ventilation through a laryngeal mask in terms of success rate of intraoperative respiratory support among patients undergoing a 30-minute general anesthesia session.

Methods: Single-center, randomized, noninferiority trial conducted in Italy between May 2022 and June 2023 and involving American Society of Anesthesiologists class I and II patients undergoing general anesthesia for operative hysteroscopy.

Evaluation of the potential for lung recruitment with the Recruitment-to-Inflation ratio during general anesthesia.

Background: During general anesthesia, the effect of positive end-expiratory pressure (PEEP) on lung injury depends on the potential for lung recruitment, which is variable among patients. The recruitment-to-inflation ratio (R/I) is measured from ventilator data during a single-breath PEEP-release maneuver, and has been proposed to assess recruitability without the need for additional equipment during acute respiratory distress syndrome. This study hypothesized that R/I reliably estimates the individual potential for lung recruitment during general anesthesia.

Omics approach to chest electrical impedance tomography reveals physiological cluster of ARDS characterised by increased respiratory drive and effort.

Background: Non-invasive assessment of respiratory drive and effort in spontaneously breathing ARDS patients is challenging, yet clinically relevant. We explored whether hierarchical clustering applied to electrical impedance tomography (EIT- a radiation-free non-invasive lung imaging technique) identifies ARDS sub-phenotypes with increased drive and effort.

Results: Thirty intubated patients with ARDS on assisted mechanical ventilation were monitored by EIT and esophageal pressure during a decremental positive end-expiratory pressure (PEEP) trial.

Unveiling an Arpp-19 phosphorylation switch that grants chromosome stability.

During cell division, the onset of mitosis is granted by activation of cyclin B-dependent kinase 1 (Cdk1), master mitotic kinase, coordinated with inactivation of Cdk1-counteracting phosphatases. PP2A-B55, a major of these phosphatases, is inhibited in mitosis by Arpp-19 and Ensa, two very similar proteins, once phosphorylated by the Cdk1-stimulated kinase Greatwall (Gwl). We show here that Arpp-19 is also phosphorylated in a Cdk1-dependent manner at serine 23, a site missing in mammalian Ensa, in mitotic human cells and dephosphorylated at this site during mitosis exit.

Stewart's theory and acid-base changes induced by crystalloid infusion in humans: a randomized physiological trial.

Background: Stewart's acid-base theory states that, under isocapnic conditions, crystalloid infusion affects plasma pH due to changes in strong ion difference and total weak acid concentration: a comprehensive study also assessing renal response and hemodilution effects has not been conducted in humans. We aimed to evaluate Stewart's approach during crystalloid infusion in humans.

Methods: In this randomized trial, patients undergoing surgery with minimal blood losses were randomized to receive to normal saline (chloride content 154 mEq/L, strong ion difference 0 mEq/L), lactated Ringer's (chloride content 112 mEq/L, strong ion difference 29 mEq/L) or Crystalsol (chloride content 98 mEq/L, strong ion difference 50 mEq/L): patients received 10 ml/kg immediately after intubation, and 20 ml/kg after 2 h.

Heterogeneity in clinical judgment of septal lead position and capture type in left bundle branch area pacing.

Background: Determining capture type and septal lead location during left bundle branch area pacing (LBBAP) relies on criteria obtained during implantation. However, during follow-up, the interpretation of left bundle branch (LBB) capture largely depends on QRS morphology, which is not so straightforward in LBBAP.

Objective: This study aimed to investigate the inter- and intraobserver agreement, as well as the accuracy of clinical judgment of the electrocardiogram (ECG) in determining LBB-capture and septal lead position in patients undergoing LBBAP implantation.

Acute Electrical Synchronization Achieved With Dynamic Atrioventricular Delays During Biventricular and Left Ventricular MultiPoint Pacing.

Background: Cardiac resynchronization therapy (CRT) response relies on 2 factors: when and where to pace. These factors may be enhanced by dynamic atrioventricular delays (AVDs) (eg, SyncAV CRT, Abbott Cardiovascular, Abbott Park, IL) and multisite left ventricular (LV) pacing (eg, MultiPoint Pacing [MPP], Abbott). Their individual and combined synchronization contributions have not been evaluated across a comprehensive spectrum of pacing configurations.

Endocardial gaglionated plexi ablation in different vagally-mediated clinical settings: From cardioneuroablation to cardio-neuromodulation.

Cardioneuroablation (CNA) is now recognized as a safe and effective method in patients with cardioinhibitory neurocardiogenic syncope (CNCS), especially in young patients in order to avoid or prolong, as much as possible, the timing of definitive cardiac pacing. Several investigations have shown beneficial and very satisfactory results with a standard non-extensive endocardial ablation, aimed at identifying high-amplitude fragmented signals in the right and left atria. Despite this, the current scientific debate is focused about a proposal on an ablative method, even more individualized than CNA (at least as a first approach), considering that a standardized approach, especially in the left atrium, could expose CNCS patients with a good prognosis to an excessive risk of complications.

Pacing of the specialized His Purkinje conduction system: 'HOW and FOR WHOM'.

The human heart's conduction system consists of specialized cardiomyocytes that generate and transmit electrical impulses, leading to the rhythmic and synchronized contraction of the atria and ventricles, which is crucial for the normal cardiac cycle. In conduction system pacing (CSP), pacing leads are placed in the His bundle region and the left bundle branch area to achieve physiological cardiac activation. This method offers a more natural alternative to the myocardial stimulation provided by conventional right ventricular pacing and biventricular pacing.

Assessing fluid responsiveness by using functional hemodynamic tests in critically ill patients: a narrative review and a profile-based clinical guide.

Fluids are given with the purpose of increasing cardiac output (CO), but approximately only 50% of critically ill patients are fluid responders. Since the effect of a fluid bolus is time-sensitive, it diminuish within few hours, following the initial fluid resuscitation. Several functional hemodynamic tests (FHTs), consisting of maneuvers affecting heart-lung interactions, have been conceived to discriminate fluid responders from non-responders.

Chromosome alignment and Kif18A action rely on spindle-localized control of Cdk1 activity.

Introduction: During mitosis, chromosome alignment at the mitotic spindle equator grants correct chromosome segregation and proper nuclei formation in daughter cells. The kinesin 8 family member Kif18A plays a crucial role for chromosome alignment by localizing at the kinetochore-microtubule (K-MT) plus ends to dampen MT dynamics and stabilize K-MT attachments. Kif18A action is directly antagonized by the master mitotic kinase cyclin B-dependent kinase 1 (Cdk1) and is promoted by protein phosphatase 1 (PP1).

Early physiologic changes after awake prone positioning predict clinical outcomes in patients with acute hypoxemic respiratory failure.

Purpose: The optimal physiologic parameters to monitor after a session of awake prone positioning in patients with acute respiratory failure are not well understood. This study aimed to identify which early physiologic changes after the first session of awake prone positioning are linked to the need for invasive mechanical ventilation or death in patients with acute respiratory failure.

Methods: We performed a secondary analysis of a prospective cohort study of adult patients with acute respiratory failure related to coronavirus disease 2019 (COVID-19) treated with awake prone positioning.

Assessment of ventricular electrical heterogeneity in left bundle branch pacing and left ventricular septal pacing by using various electrophysiological methods.

Introduction: Left bundle branch area pacing (LBBAP) comprises pacing at the left ventricular septum (LVSP) or left bundle branch (LBBP). The aim of the present study was to investigate the differences in ventricular electrical heterogeneity between LVSP, LBBP, right ventricular pacing (RVP) and intrinsic conduction with different dyssynchrony measures using the ECG, vectorcardiograpy, ECG belt, and Ultrahigh frequency (UHF-)ECG.

Methods: Thirty-seven patients with a pacemaker indication for bradycardia or cardiac resynchronization therapy underwent LBBAP implantation.

Representation of obesity in contemporary atrial fibrillation ablation randomized controlled trials.

Background: The prevalence and impact of obesity on outcomes of atrial fibrillation (AF) ablation randomized controlled trials (RCTs) have not been well studied.

Objective: To examine the proportion of participants with obesity enrolled in RCTs of AF ablation and outcomes of ablation when subgroup analysis of participants with obesity were available.

Methods: We systematically searched PubMed and EMBASE for AF ablation RCTs published between January 1, 2015 to May 31, 2022.

Recruitment-to-inflation ratio to assess response to PEEP during laparoscopic surgery: A physiologic study.

Study Objective: During laparoscopic surgery, the role of PEEP to improve outcome is controversial. Mechanistically, PEEP benefits depend on the extent of alveolar recruitment, which prevents ventilator-induced lung injury by reducing lung dynamic strain. The hypotheses of this study were that pneumoperitoneum-induced aeration loss and PEEP-induced recruitment are inter-individually variable, and that the recruitment-to-inflation ratio (R/I) can identify patients who benefit from PEEP in terms of strain reduction.

Recruitment-to-inflation ratio for bedside PEEP selection in acute respiratory distress syndrome.

In acute respiratory distress syndrome, the role of positive end-expiratory pressure (PEEP) to prevent ventilator-induced lung injury is controversial. Randomized trials comparing higher versus lower PEEP strategies failed to demonstrate a clinical benefit. This may depend on the inter-individually variable potential for lung recruitment (i.