[Recommendations of the new S1 guidelines on airway management].

The German guidelines for airway management aim to optimize the care of patients undergoing anesthesia or intensive care. The preanesthesia evaluation is an important component for detection of anatomical and physiological indications for difficult mask ventilation and intubation. If predictors for a difficult or impossible mask ventilation and/or endotracheal intubation are present the airway should be secured while maintaining spontaneous breathing.

Videolaryngoscopy for Physician-Based, Prehospital Emergency Intubation: A Prospective, Randomized, Multicenter Comparison of Different Blade Types Using A.P. Advance, C-MAC System, and KingVision.

Background: Videolaryngoscopy is a valuable technique for endotracheal intubation. When used in the perioperative period, different videolaryngoscopes vary both in terms of technical use and intubation success rates. However, in the prehospital environment, the relative performance of different videolaryngoscopic systems is less well studied.

Effect of ischemic and pharmacological preconditioning of lower limb muscle tissue on tissue oxygenation measured by near-infrared spectroscopy--a pilot study.

Background: Ischemic or volatile anesthetic preconditioning is defined as tissue protection from impending ischemic cell damage by repetitive short periods of tissue exposure to ischemia or volatile anesthetics. Objective of this study was to elucidate, if ischemic preconditioning and pharmacological preconditioning with sevoflurane have effects on muscle tissue oxygen saturation in patients undergoing surgical revascularization of the lower limb.

Methods: In this prospective randomized pilot study ischemic and pharmacological (sevoflurane) preconditioning was performed in 40 patients with lower limb arterial occlusive disease undergoing surgical revascularization.

Airway management disasters in the ICU--lessons learned?

The C-MAC video laryngoscope substantially reduced poor glottic views and increased intubation success in ICU patients with at least one predictor for difficult intubation. However, all video-assisted and optical intubation devices have different view angles, thus producing different images with particular distortion, and even experts in 'old-fashioned' airway management need a substantial level of training with a certain device before using it safely and successfully in critical situations and patients. Video laryngoscopes, regardless of a particular brand or device, cannot be used intuitively - they require expert skills and routines to be turned into a life-saving airway management tool.

[Airwaymanagement: video-assisted airway management].

Endotracheal intubation remains the "goldstandard" in airway management. If with use of conventional techniques intubation of the patient fails, or if an anticipated difficult airway is present, video-assisted techniques may help to increase intubation success. Video-assisted techniques give the possibility to indirectly visualise the laryngeal structures with fibreoptical or camerachip-technique, and to display the videopicture on an external or integrated monitor.

The C-MAC videolaryngoscope for prehospital emergency intubation: a prospective, multicentre, observational study.

Background: In this preliminary prospective observational study at four physician-led air rescue centres, the efficacy of the C-MAC (Karl Storz, Tuttlingen, Germany), a new portable videolaryngoscope, was evaluated during prehospital emergency endotracheal intubations.

Methods: 80 consecutive patients requiring prehospital emergency intubation, treated by a physician introduced in the use of the C-MAC were enrolled in this study.

Results: Indication for prehospital intubation was trauma in 45 cases (including maxillo-facial trauma in 10 cases), cardiopulmonary resuscitation in 14 cases, and unconsciousness of neurological aetiology and cardiogenic dyspnoea in 21 cases.

A randomised, controlled crossover comparison of the C-MAC videolaryngoscope with direct laryngoscopy in 150 patients during routine induction of anaesthesia.

Background: The C-MAC® (Karl Storz, Tuttlingen, Germany) has recently been introduced as a new device for videolaryngoscopy guided intubation. The purpose of the present study was to compare for the first time the C-MAC with conventional direct laryngoscopy in 150 patients during routine induction of anaesthesia.

Methods: After approval of the institutional review board and written informed consent, 150 patients (ASA I-III) with general anaesthesia were enrolled.

First clinical evaluation of the C-MAC D-Blade videolaryngoscope during routine and difficult intubation.

In the present preliminary study we evaluated the C-MAC® D-Blade (Karl Storz, Tuttlingen, Germany), a new videolaryngoscopic C-MAC blade for difficult intubation, during both routine and difficult intubations. First, both the conventional direct laryngoscopy and the D-Blade were used in 15 consecutive patients with normal airways during routine induction of anesthesia. Second, the D-Blade was used as a rescue device in 20 of 300 (6.

Effects of cerebral hypoperfusion on bispectral index: a randomised, controlled animal experiment during haemorrhagic shock.

Background: The aim of this porcine haemorrhagic shock model was to investigate the changes of bispectral index (BIS) after slow and fast recovery of cerebral perfusion, and its correlation with plasma propofol concentrations.

Methods: After Animal Investigational Committee approval, 16 pigs during propofol anaesthesia underwent a liver trauma with severe hypotension, and were randomly assigned to receive therapy for either slow recovery (fluid resuscitation; slow group; n=8) or fast recovery of cerebral perfusion (vasopressor combined with hypertonic-saline-starch; fast group; n=8), respectively. Cerebral perfusion pressure (CPP=MAP-ICP), cerebral tissue oxygenation index (TOI), BIS, and plasma concentrations of propofol and haemoglobin were measured at baseline (Pre-shock), haemodynamic decompensation (Shock), and 5 (Therapy) and 30 min (End) after therapy, respectively.

Laryngeal tube S II, laryngeal tube S disposable, Fastrach laryngeal mask and Fastrach laryngeal mask disposable during elective surgery: a randomized controlled comparison between reusable and disposable supraglottic airway devices.

Background And Objective: Analogue disposable devices of the laryngeal tube S II (LTS II) and the Fastrach laryngeal intubation mask (ILMA, Fastrach), namely the laryngeal tube disposable (LTS-D) and the Fastrach laryngeal intubation mask disposable (Fastrach-D), have recently been introduced. The purpose of this study was to compare each reusable device with the corresponding disposable one, during routine surgery.

Methods: After informed consent, 120 American Society of Anesthesiologists I-III patients scheduled for routine minor surgery were randomly allocated to the LTS II (n = 30), the LTS-D (n = 30), the Fastrach (n = 30) and the Fastrach-D (n = 30) groups, respectively.

The C-MAC videolaryngoscope: first experiences with a new device for videolaryngoscopy-guided intubation.

We studied the efficacy of the C-MAC (Karl Storz, Tuttlingen, Germany), a new portable videolaryngoscope, in 60 patients during routine induction of anesthesia. It was possible to insert the blade (Size 3) of the C-MAC and to get a view of the glottis on the first attempt in all patients. Tracheal intubation also was successful in all 60 patients; 52 patients were intubated on the first attempt, 6 on the second, and 2 on the third.

Cerebral metabolism during deep hypothermic circulatory arrest vs moderate hypothermic selective cerebral perfusion in a piglet model: a microdialysis study.

Background: Few data exist regarding antegrade selective cerebral perfusion (ASCP) and its application in newborn and juvenile patients. Clinical data suggest ASCP alone to be superior to deep hypothermic circulatory arrest (DHCA); however, the effects of moderate hypothermia during ASCP on cerebral metabolism in this patient population are still unclear.

Methods: After obtaining the approval from animal investigation committee, 16 piglets were randomly assigned to circulatory arrest combined with either ASCP at 27 degrees C or DHCA at 18 degrees C for 90 min.

Laryngeal tube S II, ProSeal laryngeal mask, and EasyTube during elective surgery: a randomized controlled comparison with the endotracheal tube in nontrained professionals.

Background And Objective: EasyTube (EZT), ProSeal laryngeal mask airway (PLMA), and Laryngeal tube S II (LTS II) have recently been introduced as supraglottic airway devices and have been proposed as emergency airway alternatives. The purpose of this study was to compare the performance of the three devices, if used by anaesthesiologists without extensive hands-on training, with the endotracheal tube during routine surgical procedures.

Methods: After informed consent, 88 ASA I-II patients scheduled for routine minor surgery were randomly allocated to EZT (n=22), PLMA (n=22), and LTS II (n=22) groups and the endotracheal tube (n=22) group, respectively.

Cerebral effects of three resuscitation protocols in uncontrolled haemorrhagic shock: a randomised controlled experimental study.

Background: To compare haemodynamic and cerebral variables during aggressive fluid resuscitation vs. administration of a hypertonic starch solution (HS) combined with either noradrenaline [norepinephrine] or arginine vasopressin in an animal model of uncontrolled haemorrhagic shock.

Methods: After Animal Investigational Committee approval, 24 anaesthetised pigs underwent a liver trauma.

Impact of different compression-ventilation ratios during basic life support cardiopulmonary resuscitation.

Background: The 2005 revised guidelines for cardiopulmonary resuscitation (CPR) suggest a universal compression-to-ventilation (C:V) ratio of 30:2. The effects of this ratio in a realistic CPR scenario have not been investigated completely.

Material And Methods: After 4 min of untreated ventricular fibrillation (VF), 24 pigs were randomly assigned to 6 min of basic-life support (BLS) CPR with 21% oxygen, and either (1) chest compressions only ("CC" group, n=8), or (2) cycles of 30 compressions followed by two breaths with a self-inflating bag (Fio2 0.

Regional and local brain oxygenation during hemorrhagic shock: a prospective experimental study on the effects of small-volume resuscitation with norepinephrine.

Background: Patients with uncontrolled hemorrhage may benefit if resuscitation with large amounts of fluids is replaced by a small volume or vasopressor until surgery. Norepinephrine (NE) is commonly used as a vasopressor to control hypotension. The purpose of this study was to compare the effects of hypertonic-hyperoncotic saline starch solution (HHS) either alone or combined with NE on brain tissue oxygen pressure (PbtO2) and brain oxygen saturation (rSO2) in a model of uncontrolled hemorrhage.

Measurement of blood flow index during antegrade selective cerebral perfusion with near-infrared spectroscopy in newborn piglets.

Background: Neonates with complex congenital heart defects have traditionally undergone surgery during deep hypothermic cardiac arrest (HCA). Selective cerebral perfusion (SCP) is thought to minimize ischemic brain injury by providing adequate cerebral blood flow. We investigated SCP with different flow rates compared with HCA with respect to cerebral perfusion and tissue oxygenation as assessed by near-infrared spectroscopy.

Release of protein S100B in haemorrhagic shock: effects of small volume resuscitation combined with arginine vasopressin.

Background: The present study was designed to evaluate the effect of conventional fluid resuscitation and small volume resuscitation alone and combined with arginine vasopressin (AVP) on cerebral perfusion pressure (CPP) and protein S100B during experimental haemorrhagic shock.

Material And Methods: Thirty anaesthetised pigs underwent a penetrating liver trauma. Following haemodynamic decompensation, pigs received either (1) a combination of crystalloid (40 mL kg(-1)) and colloid (20 mL kg(-1)) solutions (fluid, n=10), (2) hypertonic-hyperoncotic solution (HHS; 4 mL kg(-1)) combined with normal saline (HHS+NS; n=10) or (3) HHS combined with AVP (0.

Impact of norepinephrine and fluid on cerebral oxygenation in experimental hemorrhagic shock.

Few data exist regarding resuscitation of hypovolemic shock in infants, and alternative strategies such as vasopressor therapy merit further evaluation. However, the effects of norepinephrine on cerebral perfusion and oxygenation during hemorrhagic shock in the pediatric population are still unclear. Eight anesthetized piglets were subjected to hypotension by blood withdrawal of 25 mL/kg.

Arginine vasopressin during sinus rhythm: effects on haemodynamic variables, left anterior descending coronary artery cross sectional area and cardiac index, before and after inhibition of NO-synthase, in pigs.

Unlabelled: We have shown previously that arginine vasopressin (AVP) given during sinus rhythm increases mean arterial blood pressure (MAP) and left anterior descending (LAD) coronary artery cross sectional area. AVP was assumed to result in vasodilatation via activation of the endothelial nitric oxide system. The purpose of the present study was to assess the effects of AVP before and after NO-inhibition.

Revised resuscitation guidelines: adrenaline versus adrenaline/vasopressin in a pig model of cardiopulmonary resuscitation--a randomised, controlled trial.

Background: Synergistic effects of adrenaline (epinephrine) and vasopressin may be beneficial during cardiopulmonary resuscitation. However, it is unknown whether either adrenaline alone or an alternating administration of adrenaline and vasopressin is better for restoring vital organ perfusion following basic life support (BLS) according to the revised algorithm with a compression-to-ventilation (c/v) ratio of 30:2.

Material And Methods: After 4min of ventricular fibrillation, and 6min of BLS with a c/v ratio of 30:2, 16 pigs were randomised to receive either 45microg/kg adrenaline, or alternating 45microg/kg adrenaline and 0.

The reliability of pulse contour-derived cardiac output during hemorrhage and after vasopressor administration.

Background: Reliable measurement of cardiac output (CO) is important in the critically ill. Pulse contour-derived CO (PCCO) has been evaluated during stable hemodynamics, but is sensitive to changes in vascular tone and has not been validated under conditions of changing hemodynamics. Furthermore, PCCO requires calibration for the individual vascular impedance by transpulmonary thermodilution CO (TPCO), and the required frequency of recalibration to maintain accurate measurements, especially during changing conditions, has not been confirmed.

Small volume resuscitation: a randomized controlled trial with either norepinephrine or vasopressin during severe hemorrhage.

Background: The present study was designed to evaluate the effects of hypertonic-hyperoncotic hydroxyethyl starch solution (HHS) combined with either norepinephrine (NE) or arginine vasopressin (AVP) on cerebral perfusion pressure (CPP) and brain metabolism after hemorrhagic shock.

Methods: Fourteen pigs were subjected to uncontrolled liver bleeding until hemodynamic decompensation followed by resuscitation using HHS (4 mL/kg) combined with either NE (bolus of 1000 microg; 60 microg/kg/hr; n = 7) or AVP (bolus of 10 U; 2 U/kg/hr; n = 7), respectively. Extracellular cerebral concentrations of glucose, glycerol, lactate, and the lactate/pyruvate ratio were assessed by microdialysis.

Cerebral metabolism assessed with microdialysis in uncontrolled hemorrhagic shock after penetrating liver trauma.

In a porcine model of uncontrolled hemorrhagic shock, we evaluated the effects of fluid resuscitation versus arginine vasopressin (AVP) combined with hypertonic-hyperoncotic hydroxyethyl starch solution (HHS) on cerebral perfusion pressure (CPP) and on cerebral metabolism using intracerebral microdialysis. Sixteen anesthetized pigs were subjected to uncontrolled liver bleeding until hemodynamic decompensation, followed by resuscitation using either fluid (n = 8) or AVP/HHS (n = 8). Thirty minutes after drug administration, bleeding was controlled by manual compression, and colloid and crystalloid solutions were administered in both groups.

Brain tissue oxygen pressure and cerebral metabolism in an animal model of cardiac arrest and cardiopulmonary resuscitation.

Objective: Direct measurement of brain tissue oxygenation (PbtO2) is established during spontaneous circulation, but values of PbtO2 during and after cardiopulmonary resuscitation (CPR) are unknown. The purpose of this study was to investigate: (1) the time-course of PbtO2 in an established model of CPR, and (2) the changes of cerebral venous lactate and S-100B.

Methods: In 12 pigs (12-16 weeks, 35-45 kg), ventricular fibrillation (VF) was induced electrically during general anaesthesia.