Metabolic effects as a cause of myotoxic effects of fluoroquinolones.

Objectives: To investigate if fluoroquinolones (FQs) influence skeletal muscle metabolism of healthy and malignant hyperthermia susceptible (MHS) pigs.

Materials And Methods: After approval from of the Animal Care Committee, 10 MHS pigs, and 6 MHS pigs were anesthetized with hemodynamic and systemic metabolic monitoring. Microdialysis catheters were placed intramuscularly.

Effect of caffeine on intrinsic mechanical properties of normal and malignant hyperthermia-susceptible muscle.

Introduction: Malignant hyperthermia (MH) is a potentially lethal anesthesic complication. Pathological symptoms develop after exposure to triggering substances. It remains uncertain whether cellular alterations pre-exist.

[Malignant hyperthermia].

Malignant hyperthermia (MH) is a rare hereditary, mostly subclinical myopathy. Trigger substances, such as volatile anesthetic agents and the depolarizing muscle relaxant succinylcholine can induce a potentially fatal metabolic increase in predisposed patients caused by a dysregulation of the myoplasmic calcium (Ca) concentration. Mutations in the dihydropyridine ryanodine receptor complex in combination with the trigger substances are responsible for an uncontrolled release of Ca from the sarcoplasmic reticulum.

[Guidance of axillary multiple injection technique for plexus anesthesia. Ultrasound versus nerve stimulation].

Background: Ultrasound guidance is still a young method in regional anesthesia when compared to nerve stimulation and only a few studies exist comparing these two techniques in an axillary multiple injection approach.

Aim: This prospective, randomized, observer-blinded study compared an ultrasound-guided (SONO) quadruple injection axillary block (out of plane, perineural) with a nerve stimulation-guided (STIM) triple injection axillary block for upper limb surgery.

Material And Methods: A total of 60 patients were randomized to either the SONO (n = 30) or STIM (n = 30) group.

The effect of succinylcholine on malignant hyperthermia events in susceptible swine.

Background: While the impact of volatile anaesthetics to induce malignant hyperthermia (MH) is abundantly clear, the role of succinylcholine still remains controversial. To evaluate the influence of succinylcholine on porcine MH events, the authors investigated the hemodynamic and metabolic responses in MH susceptible (MHS) and non-susceptible (MHN) swine following either succinylcholine or halothane application alone or a combination of both substances.

Methods: With approval of the local animal care committee 27 MHS and 30 MHN pigs were anaesthetized and mechanically ventilated.

A minimal-invasive metabolic test detects malignant hyperthermia susceptibility in a patient after sevoflurane-induced metabolic crisis.

Malignant hyperthermia is a rare but life-threatening complication of general anesthesia in predisposed patients usually triggered by potent inhalation anesthetics and/or the depolarizing muscle relaxant succinylcholine. The authors present a case of delayed sevoflurane-induced malignant hyperthermia in a 21-year-old male patient that was sufficiently treated by discontinuation of trigger agent application and dantrolene infusion. After surviving an MH episode diagnostic procedures are indicated to increase patient safety.

Minimally invasive monitoring of skeletal muscle hypermetabolism induced by the phosphodiesterase-III-inhibitor milrinone and sodium fluoride.

Objectives: We hypothesized that the phosphodiesterase-III-inhibitor milrinone and the non-specific G-protein activator sodium fluoride increase the skeletal muscular lactate levels as a sign of a hypermetabolic response.

Methods: With approval of the local animal care committee Sprague-Dawley rats were killed and artificially perfused either with Ringer's solution or sodium fluoride 110 mM, while milrinone 1.32 mM or Ringer's solution at 1 μl/min was applied via microdialysis probes in both hind limbs.

Sevoflurane as a potential replacement for halothane in diagnostic testing for malignant hyperthermia susceptibility: results of a preliminary study.

Background: To diagnose malignant hyperthermia (MH) susceptibility, muscle bundles are exposed to halothane and caffeine. We investigated whether sevoflurane, which is more clinically relevant but less potent of an anesthetic, could replace halothane in diagnostic MH testing.

Methods: With prior written consent, muscle bundles from 6 malignant hyperthermia susceptible (MHS) and 5 non-susceptible (MHN) individuals were exposed to increasing concentrations of sevoflurane (1.

Succinylcholine in malignant hyperthermia: evaluation of a novel in vivo model.

Introduction: Malignant hyperthermia (MH) is a potentially lethal anesthetic complication characterized by muscle hypermetabolism and generalized rigor. The exact mechanism of succinylcholine as an MH trigger cannot be examined in existing in vitro models. Therefore, a novel in vivo model was used to examine the metabolic response to succinylcholine.

Fluoroquinolones influence the intracellular calcium handling in individuals susceptible to malignant hyperthermia.

Introduction: The mechanisms of fluoroquinolone-induced myotoxicity are unknown but an involvement of intracellular calcium handling is suspected. An in vitro contracture test used to investigate cellular processes in malignant hyperthermia (MH) can be applied to study the effects of fluoroquinolones.

Methods: With approval of the local ethics committee, muscle biopsies of 18 MH susceptible (MHS) and 12 MHS non-susceptible (MHN) pigs were performed.

Magnesium does not influence the clinical course of succinylcholine-induced malignant hyperthermia.

Background: Malignant hyperthermia (MH) is a potentially lethal hypermetabolic syndrome. Volatile anesthetics and/or succinylcholine lead to an increase of the intracellular calcium concentration resulting in activation of various intracellular processes. A production of carbon dioxide, and later lactate, are early signs of increased cellular energy consumption.

Statins alter intracellular calcium homeostasis in malignant hyperthermia susceptible individuals.

Aims: Statines, HMG-CoA reductase inhibitors, are widely used to treat hypercholesterinemia. These substances are well tolerated, but myotoxic effects have been reported. The exact mechanisms of the induced myotoxicity are unknown but an involvement of intracellular calcium handling is suspected.

In-vitro contracture testing for susceptibility to malignant hyperthermia: can halothane be replaced?

Background: Malignant hyperthermia is a potentially lethal inherited hypermetabolic syndrome that develops in susceptible individuals following administration of depolarising neuromuscular relaxants or volatile anaesthetics. Genetic analysis can only confirm a diagnosis of malignant hyperthermia in about 70%, and in the remainder an in-vitro contracture test, with halothane and caffeine, on muscle obtained from open muscle biopsy is required to establish the diagnosis. As the licence for clinical use of halothane expired in 2005, its continuing availability is in doubt.

Minimally invasive metabolic testing for malignant hyperthermia susceptibility: a systematic review of the methodology and results.

Importance Of The Field: Malignant hyperthermia (MH) is a potentially lethal hypermetabolic syndrome that develops in susceptible individuals exposed to volatile anesthetics or depolarizing neuromuscular blocking agents. Because genetic screening is successful only in 30 - 50% of all suspected cases, contracture testing following an open muscle biopsy is performed to diagnose MH susceptibility. Two different protocols exist, the in vitro contracture test (IVCT) for Europe and the caffine halothane contracture test for the US.

Intramuscular injection of malignant hyperthermia trigger agents induces hypermetabolism in susceptible and nonsusceptible individuals.

Background And Objective: A new minimally invasive metabolic test for the diagnosis of susceptibility for malignant hyperthermia measuring intramuscular p(CO(2)) and lactate following local application of caffeine and halothane in humans was recently proposed. The present study tested the hypothesis that a more simplified test protocol allows a differentiation between malignant hyperthermia susceptible (MHS) and malignant hyperthermia nonsusceptible (MHN) and control individuals.

Methods: With approval of the local ethics committee and informed consent, microdialysis and p(CO(2)) probes with attached microtubing were placed into the lateral vastus muscle of six MHS, seven MHN and seven control individuals.

[Malignant hyperthermia and its differential diagnosis].

Hyperthermia affects almost all endogenous regulatory systems, where especially cardiovascular and central nervous system interactions can result in life threatening complications. This review illustrates signs and symptoms, pathophysiology and therapeutic options of the three most common hyperthermic syndromes in neurology: malignant hyperthermia, serotonine-syndrom and malignant neuroleptic syndrome. The aim of this contribution is to enable the reader to make the differential diagnosis of these three disease entities.

An in-vivo metabolic test for detecting malignant hyperthermia susceptibility in humans: a pilot study.

Introduction: In vitro contracture testing to diagnose malignant hyperthermia (MH) susceptibility requires a muscle biopsy, which may be associated with severe side effects for the patient. After investigation of several different protocols, we present a less invasive metabolic test that involves IM injection of caffeine and halothane, and subsequent measurement of interstitial lactate to differentiate between MH susceptible (MHS) and MH non-susceptible (MHN) individuals.

Methods: Two microdialysis probes with attached microtubing for trigger injection were inserted into the lateral vastus muscle of eight previously diagnosed MHS patients (representing three genetic variants Gly2434Arg, Thr2206Met, and Arg614Cys), seven MHN patients, and seven control individuals.

Arteriovenous extracorporeal lung assist as integral part of a multimodal treatment concept: a retrospective analysis of 22 patients with ARDS refractory to standard care.

Background And Objectives: Pumpless arteriovenous extracorporeal lung assist is increasingly used as a rescue therapy in acute respiratory distress syndrome. Arteriovenous extracorporeal lung assist is highly efficient in eliminating carbon dioxide and allows the application of ventilator techniques that prioritize lung protection and aim to reduce ventilator-induced lung injury and remote organ dysfunction.

Methods: Retrospective data analysis performed in a 12-bed university hospital ICU.

[In-vivo diagnosis of malignant hyperthermia susceptibility: a microdialysis study].

Background: In malignant hyperthermia (MH), volatile anesthetics induce hypermetabolism, lactic acidosis and rhabdomyolysis in predisposed patients. The authors hypothesized that intramuscular caffeine and halothane application would increase local lactate concentration in MH susceptible (MHS) individuals more than in non-susceptible (MHN) subjects without initiating the full MH syndrome.

Methods: In 14 MHS, 12 MHN and 7 control individuals, microdialysis probes were placed in the rectus femoris muscle and perfused with Ringer's solution at 1 microl/min.

Intramuscular injection of sevoflurane detects malignant hyperthermia predisposition in susceptible pigs.

Background: The authors hypothesized that intramuscular sevoflurane injection allows diagnostic differentiation between malignant hyperthermia-susceptible (MHS) and -nonsusceptible (MHN) pigs by measurement of intramuscular lactate and carbon dioxide partial pressure (PCO2), and that dantrolene reduces the sevoflurane-induced PCO2 increase.

Methods: With approval of the local animal care committee, microdialysis probes with attached microtubing for sevoflurane injection were placed in the adductor muscles of nine MHS and six MHN pigs, and PCO2 probes with microtubing were positioned in the triceps muscle of eight MHS and six MHN pigs. After equilibration, sevoflurane boluses at different concentrations and a sevoflurane-dantrolene bolus were injected synchronously.

Differential effects of volatile and intravenous anesthetics on the activity of human TASK-1.

Volatile anesthetics have been shown to activate various two-pore (2P) domain K(+) (K(2P)) channels such as TASK-1 and TREK-1 (TWIK-related acid-sensitive K(+) channel), and mice deficient in these channels are resistant to halothane-induced anesthesia. Here, we investigated whether K(2P) channels were also potentially important targets of intravenous anesthetics. Whole cell patch-clamp techniques were used to determine the effects of the commonly used intravenous anesthetics etomidate and propofol on the acid-sensitive K(+) current in rat ventricular myocytes (which strongly express TASK-1) and selected human K(2P) channels expressed in Xenopus laevis oocytes.

A minimally invasive metabolic test with intramuscular injection of halothane 5 and 6 vol% to detect probands at risk for malignant hyperthermia.

We hypothesised that intramuscular halothane injection increases local Pco(2) concentrations in malignant hyperthermia susceptible (MHS) but not in non-susceptible (MHN) individuals. Pco(2) probes with attached microtubing catheters for halothane injection were placed into the lateral vastus muscle of eight MHS and eight MHN probands. Following equilibration, a single bolus of 200 microl halothane 5 and 6 vol% was injected.

[Anesthesia in pediatric neurosurgery].

Due to the complexity of neurosurgical and neuroradiologic interventions and diagnostic procedures in pediatric patients the anesthesiologist is particularly challenged. Anesthesiological management in neuropediatric interventions necessitates both profound knowledge of pediatric anesthesia and thorough understanding of neurological pathophysiology. This review describes in detail neuropediatric anesthesiology with an emphasis on airway management, intraoperative positioning, volume therapy and intraoperative monitoring.