Efficiency of passive activated carbon anaesthetic gas capturing systems during simulated ventilation.

Background: Interest in passive flow filter systems to remove sevoflurane from anaesthetic machine exhaust have increased recently to mitigate the environmental impact of volatile anaesthetics. These filter systems consist of chemically activated carbon, with limited evidence on their performance characteristics. We hypothesised that their efficiency depends on filter material.

Comparison of Force Distribution during Laryngoscopy with the C-MAC D-BLADE and Macintosh-Style Blades: A Randomised Controlled Clinical Trial.

: The geometry of a laryngoscope's blade determines the forces acting on the pharyngeal structures to a relevant degree. Knowledge about the force distribution along the blade may prospectively allow for the development of less traumatic blades. Therefore, we examined the forces along the blades experienced during laryngoscopy with the C-MAC D-BLADE and blades of the Macintosh style.

Effective volume of rebreathed air during breathing with facepieces increases with protection class and decreases with ambient airflow.

Wearing facepieces is discussed in the context of increasing the volume of rebreathed air. We hypothesized that rebreathed air volume increases with increasing filtering facepiece (FFP) class and that persons breathing via facepieces compensate for the additional dead-space. We have determined the effective amount of rebreathed air for a surgical masks and FFP2 and FFP3 respirators in a physical model and determined tidal volumes, breathing frequency, blood oxygen saturation, and transcutaneously measured blood carbon dioxide partial pressure (PCO2) in lung-healthy subjects breathing without and with facepieces at rest and during exercising on a recumbent ergometer.

Comparative usability of manual defibrillators - A human factors study.

Background: A manual defibrillator represents key equipment for resuscitation of cardiac arrest scenario. Improper or slow operation of a defibrillator may adversely affect acute care. A self-explanatory interface facilitates handling and decreases the risk of operating errors.

Calculating intrinsic positive end-expiratory pressure from end-expiratory flow in mechanically ventilated children-A study in physical models of the pediatric respiratory system.

Rationale: The high resistance of pediatric endotracheal tubes (ETTs) exposes mechanically ventilated children to a particular risk of developing intrinsic positive end-expiratory pressure (iPEEP). To date, determining iPEEP at the bedside requires the execution of special maneuvers, interruption of ventilation, or additional invasive measurements. Outside such interventions, iPEEP may be unrecognized.

Establishment and validation of intravenous anesthesia with dexmedetomidine for pigs under assisted spontaneous breathing: A preclinical model of intensive care conditions.

Large animal models are frequently used to investigate new medical approaches. In most cases, animals are kept under general anesthesia and mandatory mechanical ventilation during the experiments. However, in some situations assisted spontaneous breathing is essential, e.

Understanding pediatric ventilation in the operative setting. Part I: Physical principles of monitoring in the modern anesthesia workstation.

The modern anesthesia workstation provides a wealth of information some of which is of particular interest when it comes to optimizing ventilation settings. This knowledge gains even more importance in the therapy of pediatric patients. In the absence of evidence-based recommendations on optimal ventilation settings in pediatric patients, the evaluation of individual factors becomes crucial and challenging at the same time.

Understanding pediatric ventilation in the operative setting. Part II: Setting perioperative ventilation.

Approaches toward lung-protective ventilation have increasingly been investigated in recent years. Despite evidence being found in adults undergoing surgery, data in younger children are still scarce and controversial. From a physiological perspective, however, the continuously changing characteristics of the respiratory system from birth through adolescence require an approach based on the analysis of each individual patient.

Incidence of gastric insufflation at high compared with low laryngeal mask cuff pressure: A randomised controlled cross-over trial.

Background: The success of ventilation with a laryngeal mask depends crucially on the seal between the mask and the periglottic tissue. Increasing the laryngeal mask's cuff volume is known to reduce oral air leakage but may lead to gastric insufflation.

Objective: We hypothesised that a lower cuff pressure would result in less gastric insufflation.

Comprehensive evaluation of manikin-based airway training with second generation supraglottic airway devices.

Background: Supraglottic airway devices (SADs) are an essential second line tool during difficult airway management after failed tracheal intubation. Particularly for such challenging situations the handling of an SAD requires sufficient training. We hypothesized that the feasibility of manikin-based airway management with second generation SADs depends on the type of manikin.

[Airway Management in Thoracic Anesthesia with Double-Lumen Tube].

Lung separation and isolation with accomplished one-lung ventilation plays a key role in the airway management for thoracic surgery. Spectrum of indication contains thoracic surgery, procedure- and patient-dependent factors. Usually lung isolation is achieved with a double-lumen tube or a bronchial blocker.

Low-pressure monopolar electroresection of the prostate for glands sized > 70 vs. < 70 cc performed with continuous irrigation and suprapubic suction: perioperative and long-term outcome.

Purpose: To evaluate long-term efficacy and safety of low-pressure transurethral resection of the prostate for prostates < 70 cc (group 1) vs. > 70 cc (group 2).

Patients And Methods: In this study patients operated with monopolar TURP between 2009 and 2012 were evaluated retrospectively.

Pressure-flow characteristics of breathing systems and their components for pediatric and adult patients.

Background: Breathing circuits connect the ventilator to the patients' respiratory system. Breathing tubes, connectors, and sensors contribute to artificial airway resistance to a varying extent. We hypothesized that the flow-dependent resistance is higher in pediatric breathing systems and their components compared to respective types for adults.

Coaxial Tubing Systems Increase Artificial Airway Resistance and Work of Breathing.

Background: Tubing systems are an essential component of the ventilation circuit, connecting the ventilator to the patient's airways. Coaxial tubing systems incorporate the inspiratory tube within the lumen of the expiratory one. We hypothesized that by design, these tubing systems increase resistance to air flow compared with conventional ones.

Application of the Novel Ventilation Mode FLow-Controlled EXpiration (FLEX): A Crossover Proof-of-Principle Study in Lung-Healthy Patients.

Background: Traditionally, mechanical ventilation is achieved via active lung inflation during inspiration and passive lung emptying during expiration. By contrast, the novel FLEX (FLow-controlled EXpiration) ventilator mode actively decreases the rate of lung emptying. We investigated whether FLEX can be used during intraoperative mechanical ventilation of lung-healthy patients.

Intratidal recruitment/derecruitment persists at low and moderate positive end-expiratory pressure in paediatric patients.

In paediatric patients positive end-expiratory pressure (PEEP) is traditionally set lower than in adults. We investigated whether moderately higher PEEP improves respiratory mechanics and regional ventilation. Therefore, 40 children were mechanically ventilated with PEEP 2 and 5cmHO.

Compensating Artificial Airway Resistance via Active Expiration Assistance.

Background: Artificial airway resistance as provided by small-lumen tracheal tubes or catheters increases the risk of intrinsic PEEP (PEEPi). We hypothesized that by active expiration assistance, larger minute volumes could be generated without causing PEEPi compared with conventional mechanical ventilation when using small-lumen tracheal tubes or a cricothyrotomy catheter.

Methods: We investigated the active expiration assistance in a physical model of the respiratory system and estimated its hypothetical performance in terms of maximal flow generated with endotracheal tubes ranging from 3.

Characteristics of Double-Lumen Tubes Determine Bronchial Airway Pressure.

Objectives: To determine pressure-flow characteristics of double-lumen tubes (DLTs) with an outer diameter of 26 to 41 French and calculate bronchial pressure in a model setup and using data from patients who underwent one-lung ventilation with a DLT.

Design: Prospective experimental study and retrospective analysis of clinical measurements.

Setting: University medical center.

Pneumoperitoneum deteriorates intratidal respiratory system mechanics: an observational study in lung-healthy patients.

Background: Pneumoperitoneum during laparoscopic surgery leads to atelectasis and impairment of oxygenation. Positive end-expiratory pressure (PEEP) is supposed to counteract atelectasis. We hypothesized that the derecruiting effects of pneumoperitoneum would deteriorate the intratidal compliance profile in patients undergoing laparoscopic surgery.

The pressure drop across the endotracheal tube in mechanically ventilated pediatric patients.

Background: During mechanical ventilation, the airway pressure (Paw) is usually monitored. However, Paw comprises the endotracheal tube (ETT)-related pressure drop (∆PETT ) and thus does not reflect the pressure in the patients' lungs. Therefore, monitoring of mechanical ventilation should be based on the tracheal pressure (Ptrach ).

Flow Controlled Expiration is perceived as less uncomfortable than positive end expiratory pressure.

Recently, we presented Flow Controlled Expiration (FLEX) as a new option for lung-protective ventilation. FLEX delays the expiratory volume decrease in the lungs without prolonging the duration of expiration. Most ventilated patients nowadays receive spontaneous breathing support.