Pressure support ventilation versus continuous positive airway pressure ventilation with the ProSeal laryngeal mask airway: a randomized crossover study of anesthetized pediatric patients.

Continuous positive airway pressure (CPAP) and pressure support ventilation (PSV) improve gas exchange in adults, but there are little published data regarding children. We compared the efficacy of PSV with CPAP in anesthetized children managed with the ProSeal laryngeal mask airway. Patients were randomized into two equal-sized crossover groups and data were collected before surgery.

Positive pressure versus pressure support ventilation at different levels of PEEP using the ProSeal laryngeal mask airway.

We compared positive pressure ventilation with pressure support ventilation at different levels of positive end expiratory pressure (PEEP) using the ProSeal laryngeal mask airway (PLMA). Forty-two anaesthetized adults (ASA 1-2, aged 19 to 63 years) underwent positive pressure ventilation and then pressure support ventilation each with PEEP set at 0, 5 and 10 cmH2O in random order. Pressure support ventilation was with the inspired tidal volume (VTInsp) set at 7 ml/kg and the respiratory rate adjusted to maintain the end-tidal CO2 (ETCO2) at 40 mmHg.

Airway protection with the ProSeal laryngeal mask airway in a child.

We describe a case where a size 2 ProSeal laryngeal mask airway successfully channelled regurgitated fluid away from the respiratory tract in a 5-year-old child following an inguinal hernia repair.

Specific inhibition of cyclin-dependent kinase 4/6 by PD 0332991 and associated antitumor activity in human tumor xenografts.

PD 0332991 is a highly specific inhibitor of cyclin-dependent kinase 4 (Cdk4) (IC50, 0.011 micromol/L) and Cdk6 (IC50, 0.016 micromol/L), having no activity against a panel of 36 additional protein kinases.

The laryngeal mask airway Unique versus the Soft Seal laryngeal mask: a randomized, crossover study in paralyzed, anesthetized patients.

We tested the hypothesis that ease of insertion, oropharyngeal leak pressure, fiberoptic position, ease of ventilation, and mucosal trauma are different for the Soft Seal laryngeal mask airway (SSLM) and the laryngeal mask airway Unique (LMA-U). Ninety paralyzed, anesthetized adult patients (ASA I-II; 18-80 yr old) were studied. Both devices were inserted into each patient in random order.

Aspiration and the laryngeal mask airway: three cases and a review of the literature.

The primary limitation of the laryngeal mask airway (LMA) is that it does not reliably protect the lungs from regurgitated stomach content. We describe three cases of aspiration associated with the LMA, including the first brain injury, the first death, and the first associated with the intubating LMA, and review the 20 specific case reports of aspiration associated with the LMA that we were able to find described in the literature.

Failed obstetric tracheal intubation and postoperative respiratory support with the ProSeal laryngeal mask airway.

Unlabelled: The ProSeal laryngeal mask airway (ProSeal LMA) provides a better seal and probably better airway protection than the classic laryngeal mask airway (classic LMA). We report the use of the ProSeal LMA in a 26-yr-old female with HELLP syndrome for failed obstetric intubation and postoperative respiratory support. Both laryngoscope-guided tracheal intubation and face mask ventilation failed, but a size 4 ProSeal LMA was easily inserted and high tidal volumes obtained.

Mechanical versus manual ventilation via a face mask during the induction of anesthesia: a prospective, randomized, crossover study.

Unlabelled: One approach to make ventilation safer in an unprotected airway has been to limit tidal volumes; another one might be to limit peak airway pressure, although it is unknown whether adequate tidal volumes can be delivered. Accordingly, the purpose of this study was to evaluate the quality of automatic pressure-controlled ventilation versus manual circle system face-mask ventilation regarding ventilatory variables in an unprotected airway. We studied 41 adults (ASA status I-II) in a prospective, randomized, crossover design with both devices during the induction of anesthesia.

Administration of 100% oxygen before removal of the laryngeal mask airway does not affect postanesthetic arterial partial pressure of oxygen.

Unlabelled: Breathing 100% oxygen at the end of general anesthesia has been shown to worsen postoperative pulmonary gas exchange when an endotracheal tube is used. Counter measures, such as high positive end-expiratory pressure or the vital-capacity maneuver, may limit this effect. Such strategies, however, may be impracticable, or even contraindicated, when the laryngeal mask airway (LMA) is used.

A pilot study to evaluate the SMART BAG: a new pressure-responsive, gas-flow limiting bag-valve-mask device.

Unlabelled: Reducing inspiratory flow rate and peak airway pressure may be important to minimize the risk of stomach inflation when ventilating an unprotected airway with positive pressure ventilation. In this study, we assessed the effects of a standard self-inflating bag compared with a new pressure-responsive, inspiratory gas flow-limiting device (SMART BAG) on respiratory mechanics in 60 adult patients undergoing routine induction of anesthesia. Respiratory variables were measured using a pulmonary monitor.

Aspiration of gastric contents during use of a ProSeal laryngeal mask airway secondary to unidentified foldover malposition.

Unlabelled: The primary function of the drain tube of the ProSeal laryngeal mask airway (PLMA) is to prevent aspiration of regurgitated stomach contents. We report a case of gastric aspiration with the PLMA during a laparoscopic cholecystectomy in a 64-yr-old healthy man secondary to an unidentified foldover malposition. It is imperative that the position and patency of the drain tube be verified in all patients with the PLMA.

Routine cleaning and autoclaving does not remove protein deposits from reusable laryngeal mask devices.

Unlabelled: We tested the hypothesis that routine cleaning and autoclaving does not remove protein deposits from reusable laryngeal mask airways (LMAs). All previously used classic and flexible LMAs from a single hospital were tested. Each LMA was hand-washed in an enzymatic solution for 3 min, machine-washed with a disinfectant for 14 min at up to 85 degrees C; dried for 30 min at 75 degrees C, packaged in porous film, and autoclaved for 4 min at 134 degrees C.

Pharyngeal mucosal pressures with the laryngeal tube airway versus ProSeal laryngeal mask airway.

We tested the hypothesis that mucosal pressures are higher for the laryngeal tube airway trade mark than the ProSeal laryngeal mask airway. Fifteen fresh cadavers were studied. Microchip pressure sensors were attached to the laryngeal tube airway and ProSeal laryngeal mask airway at four similar anatomical locations (base of tongue, lateral pharynx, posterior pharynx and posterior hypopharynx) and three dissimilar locations (laryngeal tube airway trade mark, anterior and lateral hypopharynx; ProSeal laryngeal mask airway, pyriform fossa).

Sustained prolongation of the QTc interval after anesthesia with sevoflurane in infants during the first 6 months of life.

Background: Sevoflurane, an inhalational anesthetic frequently administered to infants, prolongs the QT interval of the electrocardiogram in adults. A long QT interval resulting in fatal arrhythmia may also be responsible for some cases of sudden death in infants. As the QT interval increases during the second month of life and returns to the values recorded at birth by the sixth month, we evaluated the effect of sevoflurane on the QT interval during and after anesthesia in this particular population.

Administration of oxygen before tracheal extubation worsens gas exchange after general anesthesia in a pig model.

Unlabelled: Administration of 100% oxygen before tracheal extubation is common clinical practice. We determined the effect of this technique on postoperative gas exchange in a porcine model using the multiple inert gas elimination technique. After general anesthesia with mechanical ventilation for a period of 30 min (inspiratory fraction of oxygen of 0.

Pulmonary gas exchange after cardiopulmonary resuscitation with either vasopressin or epinephrine.

Objective: It is well established that epinephrine administered during cardiopulmonary resuscitation results in pulmonary gas exchange disturbances. It is uncertain how vasopressin affects gas exchange after cardiopulmonary resuscitation.

Design: Prospective, randomized experimental study.

Augmented spontaneous breathing and pulmonary gas exchange during pneumoperitoneum.

Background And Objective: Ventilation of the lungs with positive end-expiratory pressure during pneumoperitoneum has been shown to improve the arterial partial pressure of oxygen. The implications of spontaneous breathing on pulmonary gas exchange remain unknown in this setting. We therefore sought to examine the influence of pressure-support ventilation with spontaneous breathing on gas exchange during simulated laparoscopy.

Monitoring pollution by proton-transfer-reaction mass spectrometry during paediatric anaesthesia with positive pressure ventilation via the laryngeal mask airway or uncuffed tracheal tube.

Twenty children aged 2-66 months were randomly allocated for airway management with either the laryngeal mask airway or uncuffed tracheal tube using intermittent positive pressure ventilation with a tidal volume of 8 ml.kg-1 and a respiratory rate adjusted to maintain end-expiratory carbon dioxide concentration at 5.3 kPa.

The influence of cuff volume and anatomic location on pharyngeal, esophageal, and tracheal mucosal pressures with the esophageal tracheal combitube.

Background: The authors determined the influence of cuff volume and anatomic location on pharyngeal, esophageal, and tracheal mucosal pressures for the esophageal tracheal combitube.

Methods: Twenty fresh cadavers were studied. Microchip sensors were attached to the anterior, lateral, and posterior surfaces of the distal and proximal cuffs of the small adult esophageal tracheal combitube.

Pulmonary gas exchange in coronary artery surgery patients during sevoflurane and isoflurane anesthesia.

Unlabelled: As the surgical population ages, the number of patients presenting with coronary artery disease and age-related loss of pulmonary recoil will increase. Although their influence on gas exchange in this population remains unknown, sevoflurane and isoflurane are used for an increasing variety of surgical procedures. We examined pulmonary gas exchange (multiple inert gas elimination technique) in 30 patients presenting for coronary artery bypass grafting.

The feasibility of transesophageal echocardiograph-guided right and left ventricular oximetry in hemodynamically stable patients undergoing coronary artery bypass grafting.

Unlabelled: There are no techniques available for continuous noninvasive measurement of the oxygen saturation of blood flowing through the heart. We assessed the feasibility and accuracy of transesophageal echocardiograph (TEE)-guided left ventricular (SpO2 LV) and right ventricular (SpO2 RV) oximetry. Twenty hemodynamically stable, well-oxygenated anesthetized patients (ASA physical status III, aged 51-75 yr) undergoing coronary artery bypass grafting were studied.

The Laryngeal Mask Airway ProSeal(TM) as a temporary ventilatory device in grossly and morbidly obese patients before laryngoscope-guided tracheal intubation.

Unlabelled: We determined the efficacy of the laryngeal mask airway ProSeal(TM) (PLMA) as a temporary ventilatory device in morbidly obese patients before laryngoscope-guided tracheal intubation. Sixty patients (body mass index 35--60 kg/m(2)) scheduled for elective surgery, who preferred airway management under general anesthesia, were studied. The induction of anesthesia was with midazolam/fentanyl/propofol and maintenance was with sevoflurane 1%--3% in oxygen 100%.