The impact of an algorithm-guided management of preoperative anemia in perioperative hemoglobin level and transfusion of major orthopedic surgery patients.

The aim of this study was to evaluate a laboratory-guided therapeutic algorithm of preoperative anemia. 335 patients with elective hip or knee arthroplasty were included in this retrospective before-after study. Group I (n = 101) underwent conventional preoperative procedures before algorithm implementation.

Head position angles to open the upper airway differ less with the head positioned on a support.

Introduction: The aim of the study was to assess the effects of positioning the head on a support on "head position angles" to optimally open the upper airway during bag-valve mask ventilation.

Methods: We ventilated the lungs of anesthetized adults with a bag-valve mask and the head positioned with (n = 30) or without a support (n = 30). In both groups, head position angles and ventilation parameters were measured with the head positioned in (1) neutral position, (2) in a position deemed optimal for ventilation by the investigator, and (3) in maximal extension.

Head-position angles in children for opening the upper airway.

Aims: Inexperienced health-care-providers may encounter severe problems to ventilate an unconscious child. Designing a ventilating device that could indicate how to open an upper airway correctly may be beneficial. Neutral position in young children and slight head extension in older children is recommended, although the optimal head angle is not clear.

Anaesthesia in prehospital emergencies and in the emergency room.

Aims: To review anaesthesia in prehospital emergencies and in the emergency room, and to discuss guidelines for anaesthesia indication; pre-oxygenation; anaesthesia induction and drugs; airway management; anaesthesia maintenance and monitoring; side effects and training.

Methods: A literature search in the PubMed database was performed and 87 articles were included in this non-systematic review.

Conclusions: For pre-oxygenation, high-flow oxygen should be delivered with a tight-fitting face-mask provided with a reservoir.

The mouth-to-bag resuscitator during standard anaesthesia induction in apnoeic patients.

Aim: Ventilation of a non-intubated emergency patient by inexperienced rescuers with a standard bag-valve device may result in high inspiratory flow rates and subsequently high airway pressures with stomach inflation. Therefore, a self-inflating bag has been developed that requires lay rescuers to blow up a single-use balloon inside an adult bag-valve device, which, in turn, displaces air within the bag towards the patient. This concept has been compared to standard adult bag-valve devices earlier in bench models but not in patients.

Ventilation strategies in the obstructed airway in a bench model simulating a nonintubated respiratory arrest patient.

Background: The Smart Bag MO(R) is an adult flow-limited bag-valve device designed to reduce the risk of stomach inflation in an unprotected airway. Its properties in severe airway obstruction are as yet unknown.

Methods: In a bench model, we evaluated respiratory mechanics and delivered tidal volumes although ventilating at airway resistances of 4, 10, and 20 cm H(2)O .

Effects of stomach inflation on haemodynamic and pulmonary function during spontaneous circulation in pigs.

Aim: Stomach inflation during mask ventilation is frequent, but the effects on haemodynamic and pulmonary function are unclear. We evaluated the effects of stomach inflation on haemodynamic and pulmonary function during spontaneous circulation in a porcine model.

Methods: Randomised prospective animal study.

Automated emergency ventilation devices in a simulated unprotected airway.

Background: Automated ventilation devices are becoming more popular for emergency ventilation, but there is still not much experience concerning the optimal ventilation mode.

Methods: In a bench model representing a non-intubated patient in respiratory and cardiac arrest, we compared a pressure-cycled with a time- and volume-cycled automated ventilation device in their completely automated modes. The main study endpoints were inspiratory time, respiratory rate, stomach inflation, and lung tidal volumes.

Effects of stomach inflation on haemodynamic and pulmonary function during cardiopulmonary resuscitation in pigs.

Aim: Stomach inflation during cardiopulmonary resuscitation (CPR) is frequent, but the effect on haemodynamic and pulmonary function is unclear. The purpose of this study was to evaluate the effect of clinically realistic stomach inflation on haemodynamic and pulmonary function during CPR in a porcine model.

Methods: After baseline measurements ventricular fibrillation was induced in 21 pigs, and the stomach was inflated with 0L (n=7), 5L (n=7) or 10L air (n=7) before initiating CPR.

Influence of ventilation strategies on survival in severe controlled hemorrhagic shock.

Objective: To investigate the effect of different ventilation settings on hemodynamic stability in severe controlled hemorrhagic shock.

Design: Prospective, randomized, controlled animal study.

Setting: Research laboratory in a university hospital.

Preoperative administration of esomeprazole has no influence on frequency of refluxes.

Study Objective: To examine the effect of esomeprazole in a fixed time setting on gastric content volume, gastric acidity, gastric barrier pressure, and reflux propensity.

Design: Randomized, controlled, double-blind trial.

Subjects: 21 healthy, ASA I physical status volunteers.

Minimizing stomach inflation versus optimizing chest compressions.

In a bench model, we evaluated a bag-valve device (Smart Bag MO) with limited maximum inspiratory gas flow developed to reduce the risk of stomach inflation in an unprotected airway. During simulated cardiopulmonary resuscitation with uninterrupted chest compressions, ventilation with the "disabled" Smart Bag MO or an adult self-inflating bag-valve device provided only adequate tidal volumes if inspiratory time was 0.5 s.

Guided insertion of the ProSeal laryngeal mask airway is superior to conventional tracheal intubation by first-month anesthesia residents after brief manikin-only training.

In the following pilot study, we compared conventional laryngoscope-guided tracheal intubation (tracheal intubation) and laryngoscope-guided, gum elastic bougie-guided ProSeal laryngeal mask airway insertion (guided ProSeal) for airway management by first-month anesthesia residents after brief manikin-only training. Five first-month residents with no practical experience of airway management were observed performing these techniques in 200 ASA I-II anesthetized, paralyzed adults. Each resident managed 40 patients, 20 in each group, in random order.

Influence of negative expiratory pressure ventilation on hemodynamic variables during severe hemorrhagic shock.

Objective: Outcome after trauma with severe hemorrhagic shock is still dismal. Since the majority of blood is present in the venous vessels, it might be beneficial to perform venous recruiting via the airway during severe hemorrhagic shock. Therefore, the purpose of our study was to evaluate the effects of negative expiratory pressure ventilation on mean arterial blood pressure, cardiac output, and short-term survival during severe hemorrhagic shock.

Effects of face mask ventilation in apneic patients with a resuscitation ventilator in comparison with a bag-valve-mask.

Bag-valve-mask ventilation in an unprotected airway is often applied with a high flow rate or a short inflation time and, therefore, a high peak airway pressure, which may increase the risk of stomach inflation and subsequent pulmonary aspiration. Strategies to provide more patient safety may be a reduction in inspiratory flow and, therefore, peak airway pressure. The purpose of this study was to evaluate the effects of bag-valve-mask ventilation vs.

Middle ear pressure changes during anesthesia with or without nitrous oxide are similar among airway devices.

We tested the hypothesis that middle ear pressure (MEP) is influenced by the choice of airway device during anesthesia with or without nitrous oxide (N2O) in the gas mixture. Eighty consecutive anesthetized, paralyzed ventilated patients (ASA physical status I-II, 18-65 yr) were randomly allocated for airway management with the orally inserted tracheal tube, classic laryngeal mask airway, ProSeal laryngeal mask airway, or laryngeal tube suction with or without N2O 66% in the gas mixture. MEP was measured from both ears in random order by a blinded observer before induction of anesthesia and every 10 min for 70 min.

Signs of inflammation after sciatic nerve block in pigs.

Nerve stimulators are widely used to assist with peripheral nerve blocks but do not eliminate the risk of nerve injury. We evaluated the histologic findings 6 h after sciatic nerve block with bupivacaine in pigs. When a motor response was still obtained with a current <0.

The influence of postural changes on gastroesophageal reflux and barrier pressure in nonfasting individuals.

Unlabelled: There is controversy regarding optimal body positioning (i.e., head-up, head-down) in awake nonfasting individuals to minimize the risk for pulmonary aspiration of gastric contents as the result of gastroesophageal reflux (GER).

Effects of decreasing inspiratory times during simulated bag-valve-mask ventilation.

During CPR, an inspiratory time of 2 s is recommended when the airway is unprotected; indicating that approximately 30% of the resuscitation attempt is spent on ventilation, but not on chest compressions. Since survival rates may not decrease when ventilation levels are relatively low, and uninterrupted chest compressions with a constant rate of approximately 100/min have been shown to be lifesaving, it may be beneficial to cut down the time spent on ventilation, and instead, increase the time for chest compressions. In an established bench model of a simulated unprotected airway, we evaluated if inspiratory time can be decreased from 2 to 1 s at different lower oesophageal sphincter pressure (LOSP) levels during ventilation with a bag-valve-mask device.

An anatomic landmark to simplify subclavian vein cannulation: the "deltoid tuberosity".

The subclavian vein is frequently used to obtain central venous access. Several landmarks exist to determine the puncture site and angle, but they may require patient manipulation and anatomic measurements. We studied the feasibility of using the deltoid tuberosity, located on the lateral aspect of the clavicle, as an anatomic landmark.

The ProSeal has a shorter life-span than the Classic laryngeal mask airway.

We tested the hypothesis that the life-span of the ProSeal laryngeal mask airway (LMA) is shorter than the Classic LMA. We also compared residual cuff volumes and changes in elastance and permeability with use. Six new size 4 ProSeal LMAs and 6 new size 4 Classic LMAs were tested.