Prone Versus Sitting Position in Neurosurgery-Differences in Patients' Hemodynamic Management.

Objective: Neurosurgery in general anesthesia exposes patients to hemodynamic alterations in both the prone and the sitting position. We aimed to evaluate the hemodynamic profile during stroke volume-directed fluid administration in patients undergoing neurosurgery either in the sitting or the prone position.

Methods: In 2 separate prospective trials, 30 patients in prone and 28 patients in sitting position were randomly assigned to receive either Ringer acetate (RAC) or hydroxyethyl starch (HES; 130 kDa/0.

Severity of Myasthenia Gravis Influences the Relationship between Train-of-four Ratio and Twitch Tension and Run-down of Rat Endplate Potentials.

Background: Train-of-four ratio (TOFR) is often used to evaluate muscle relaxation caused by neuromuscular-blocking agents (NMBAs). However, it is unknown whether TOFR reliably correlates with the first twitch tension (T1) in patients with myasthenia gravis (MG). By using rat models of experimental autoimmune MG (EAMG), the authors verified the hypothesis that the severity of MG influences the relationship between TOFR and T1.

Stroke volume-directed administration of hydroxyethyl starch (HES 130/0.4) and Ringer’s acetate in prone position during neurosurgery: a randomized controlled trial.

Purpose: General anesthesia in the prone position is associated with hypotension. We studied stroke volume (SV)-directed administration of hydroxyethyl starch (HES 130 kDa/0.4) and Ringer’s acetate (RAC) in neurosurgical patients operated on in a prone position to determine the volumes required for stable hemodynamics and possible coagulatory effects.

Blockers of adenosine A1, but not muscarinic acetylcholine, receptors improve excessive extracellular glutamate-induced synaptic depression.

We investigated adenosinergic and cholinergic effects on excessive glutamate-induced depressions of central excitatory synaptic transmissions in vitro. From the CA1 region in rat hippocampal slices, orthodromically elicited population spikes (PSs) and field excitatory postsynaptic potentials (fEPSPs) at 0.1Hz were simultaneously recorded.

Ultrasound-guided supraclavicular central venous catheterization in patients with malignant hematologic diseases.

We present two cases of central venous catheterization (CVC) in which an ultrasound-guided in-plane approach was used. Case 1 was a 60-year-old man with acute myelogenous leukemia in whom a right supraclavicular CVC was performed. He had pancytopenia (leukocytes 2,000/μL; erythrocytes 350 × 10(4)/μL; platelets 5.

Intravenous lipid emulsion only minimally influences bupivacaine and mepivacaine distribution in plasma and does not enhance recovery from intoxication in pigs.

Background: The reported successful use of IV lipid emulsions in local anesthetic intoxications is thought to be due to lipid sequestration of local anesthetics. However, controlled efficacy studies were lacking, and other mechanisms of action have also been suggested. We investigated the effect of lipid infusion on plasma concentrations and cardiovascular effects of 2 local anesthetics differing in lipophilicity, bupivacaine, and mepivacaine.

No antidotal effect of intravenous lipid emulsion in experimental amitriptyline intoxication despite significant entrapment of amitriptyline.

Intravenous lipid emulsion has been used in the resuscitative treatment of intoxications caused by local anaesthetics and tricyclic antidepressants with seemingly beneficial results. We studied the effect of intravenous lipid emulsion on the plasma concentration of amitriptyline and haemodynamic recovery in a pig model of amitriptyline intoxication. Twenty pigs were anaesthetized (1% isoflurane in 21% O(2)) and given amitriptyline 15 mg/kg intravenously for 15 min.

Pralidoxime inhibits paraoxon-induced depression of rocuronium-neuromuscular block in a time-dependent fashion.

Objective: The composite effects of organophosphorus (OP)-cholinesterase (ChE) inhibitors and oximes on the actions of nondepolarizing neuromuscular blockers in acute OP-ChE inhibitor intoxication have not been evaluated in detail. We investigated the effects of paraoxon (Pox) (an OP-ChE inhibitor) and pralidoxime (PAM) (an oxime) on the nondepolarizing neuromuscular blocking action of rocuronium.

Methods: Isometric twitch tensions of rat left phrenic nerve-hemidiaphragm preparations elicited by indirect (phrenic nerve) supramaximal stimulation at 0.

Ultrasound-guided cervical nerve root block: spread of solution and clinical effect.

Objectives: We investigated the clinical effects and accuracy of ultrasound-guided cervical nerve root block. Additionally, spinal level and spread of injected solution were confirmed by anatomic dissection of fresh cadavers. DESIGN SETTING, PATIENTS, AND INTERVENTIONS: Twelve patients diagnosed with mono-radiculopathy between C5-7 underwent ultrasound-guided nerve root block.

Sitting position for removal of pineal region lesions: the Helsinki experience.

Objective: To present a summary of anesthetic considerations for use of the sitting position in procedures to remove lesions of the occipital and suboccipital regions, with a special reference to the Helsinki experience with more than 300 operations in 1997-2007, and a retrospective study evaluating the incidence of venous air embolism (VAE) and hemodynamic stability in patients operated in the steep sitting position.

Methods: Anesthesiology reports of 72 patients with a mean (± standard deviation [SD]) age of 33 years ± 18 treated by the senior author (J.H.

Comparison of hypertonic saline and mannitol on whole blood coagulation in vitro assessed by thromboelastometry.

Background: Hypertonic saline (HS) is an alternative to mannitol for decreasing intracranial pressure in traumatic brain injury and before craniotomy. Both HS and mannitol may interfere with blood coagulation but their influence on coagulation has not been compared in controlled situations. Therefore, we evaluated different strengths of HS and 15% mannitol on blood coagulation in vitro.

[Optimal analgesic effect of continuous supraclavicular brachial plexus block with ropivacaine after shoulder surgery].

Background: Optimal dose of local anesthetics for supraclavicular brachial plexus block (BPB) is still unknown. We prospectively investigated the analgesic effect of ultrasound-guided continuous supraclavicular BPB with ropivacaine at different infusion rates.

Methods: Thirty-nine patients scheduled to undergo shoulder surgery were randomly assigned to four groups; receiving no continuous BPB (control group, n = 10), BPB with 0.

Intravenous lipid emulsion sequesters amiodarone in plasma and eliminates its hypotensive action in pigs.

Study Objective: Our objective is to investigate to what extent amiodarone is sequestered by intravenously administered lipid emulsion in plasma of pigs and whether the lipid emulsion inhibits amiodarone-induced hypotension.

Methods: Twenty anesthetized pigs received randomly 1.5 mL/kg bolus injection of olive/soybean oil-based 20% lipid emulsion (lipid group, n=10) or Ringer's acetate solution (control group, n=10) in 1 minute, followed by a continuous infusion of either solution for 30 minutes at 0.

Effects of atropine and pralidoxime on neuronal actions of paraoxon in rat hippocampal slices.

The actions of paraoxon, an organophosphorus cholinesterase (ChE) inhibitor, on central synaptic transmission and somatic excitability, and the inhibitory effects of atropine, a non-selective muscarinic acetylcholine receptor (mAChR) antagonist, and pralidoxime (PAM), an oxime, on these actions were investigated. From rat hippocampal slices, CA1-population spikes (PSs) and CA1-field excitatory postsynaptic potentials (fEPSPs) at 0.1Hz were recorded using a multi-electrode array (MEA) system.

Effect of arterial blood pressure on the arterial to end-tidal carbon dioxide difference during anesthesia induction in patients scheduled for craniotomy.

Background: Before obtaining results of arterial blood gas analysis in mechanically ventilated patients undergoing neurosurgery, the volume of ventilation is primarily adjusted according to endtidal CO2 (EtCO2). We characterized the impact of various arterial blood pressure changes on arterial PCO2 (PaCO2) to EtCO2 differences (PaCO2-EtCO2) in patients anesthetized for craniotomy.

Methods: Seventy-two elective craniotomy patients were enrolled in this prospective study.

Lack in effects of therapeutic concentrations of dexmedetomidine and clonidine on the neuromuscular blocking action of rocuronium in isolated rat diaphragms.

Background: We investigated the effects of the alpha-2 adrenoceptor agonists clonidine and dexmedetomidine on the neuromuscular blocking effect of rocuronium in vitro.

Methods: Isometric twitch tensions of rat nerve-hemidiaphragm preparations elicited by indirect (phrenic nerve) supramaximal stimulation at 0.1 Hz were evaluated.

Acute late sepsis attenuates effects of a nondepolarizing neuromuscular blocker, rocuronium, by facilitation of endplate potential and enhancement of membrane excitability in vitro.

Background: Sepsis attenuates the muscle-relaxing effects of nondepolarizing neuromuscular blockers. The authors investigated the effects of acute late sepsis on neuromuscular transmission and neuromuscular actions of rocuronium to clarify the mechanisms by which sepsis attenuates the effects of nondepolarizing neuromuscular blockers.

Methods: Sepsis was induced by cecal ligation and puncture operation.

[The mechanisms of depression by benzodiazepines, barbiturates and propofol of excitatory synaptic transmissions mediated by adenosine neuromodulation].

Adenosine is known to modulate synaptic functions through adenosine receptors and the related adenosine neuromodulatory system. Benzodiazepines, barbiturates and propofol, the main actins of which are facilitation of GABAA receptor functions, also facilitate accumulation of endogenous adenosine in the extracellular space by inhibiting adenosine uptake via adenosine transporters. The accumulated adenosine depresses excitatory synaptic transmission by decreasing transmitter release, depressing postsynaptic sensitivity and inhibiting neuronal excitability through adenosine A1 receptors and the related adenosine neuromodulatory system.

Sepsis stage dependently and differentially attenuates the effects of nondepolarizing neuromuscular blockers on the rat diaphragm in vitro.

We investigated the effects of early and late sepsis on the actions of nondepolarizing neuromuscular blockers by using a rat sepsis model induced by cecal ligation and puncture. Isometric twitch tensions of nerve-hemidiaphragm preparations elicited by indirect (phrenic nerve) supramaximal stimulation at 0.1 Hz were evaluated.

Effects of halothane and isoflurane on hyperexcitability of spinal dorsal horn neurons after incision in the rat.

Background: The aim of this study was to determine whether halothane and isoflurane used during and after surgical injury attenuate subsequent hyperexcitability of spinal dorsal horn (SDH) neurons by preventing development of central sensitization.

Methods: Activity of a wide-dynamic-range neuron of the SDH was isolated in decerebrate-spinal Sprague-Dawley rats, and neuronal activity (receptive field size and responses to nonnoxious and noxious stimuli) was recorded. A 1-cm-long incision was made through the skin, fascia, and muscle under anesthesia with halothane (1.

[Anesthetic management for a radical operation in an infant with cloacal exstrophy].

We report the anesthetic management for a radical operation in an infant with cloacal exstrophy. Diagnosis of cloacal exstrophy with meningocele was made at the 26th week of gestation. Cesarian section was performed under general anesthesia in order to keep the infant in a state of apnea to prevent aerophagia, the so-called "sleeping baby", at the 38th week of gestation.