The topics of international publications on paediatric anaesthesia from 1993 to 1998.

A comprehensive compilation of the current international literature on paediatric anaesthesia is still lacking. It was the aim of this study to identify all publications with a focus on paediatric anaesthesia, and to determine the spectrum of topics, as well as the publication type and language for the period between 1993 and 1998. All articles published in 12 major anaesthesia journals were evaluated and, additionally, a computerized, Internet-based Medline-search was performed using selected keywords. The analysis was limited to original articles, case reports, reviews and editorials. For the period between 1993 and 1998, a total of 2259 (377 per year) publications on paediatric anaesthes…

Poor outcome after hypoxia-ischemia in newborns is associated with physiological abnormalities during early recovery

"Secondary hypoxia/ischemia" (i.e. regional impairment of oxygen and substrate delivery) results in secondary deterioration after traumatic brain injury in adults as well as in children and infants. However, detailed analysis regarding critical physiological abnormalities resulting from hypoxia/ischemia in the immature brain, e.g. acid-base-status, serum glucose levels and brain temperature, and their influence on outcome, are only available from non-traumatic experimental models. In recent studies on hypoxic/asphyxic cardiac arrest in neonatal piglets, we were able to predict short-term outcome using specific physiologic abnormalities immediately after the insult. Severe acidosis, low seru…

Effects of Propofol (Intravenous Propofol Emulsion) on Cell Membranes Measured by Electrofusion and Electroporation

The influence of propofol (CAS 2078-54-8 (intravenous propofol emulsion) on cell membrane properties was investigated in vitro with techniques of cell electrofusion and cell electroporation. Human lymphoma cells and plant protoplasts were chosen as a model system. Propofol (intravenous propofol emulsion) decreased the electrofusion yield of the cells and their membrane permeability. A 50% decrease in relative electrofusion was observed in human lymphoma cells in the presence of about 0.05 mmol/l propofol (intravenous propofol emulsion) and in plant protoplasts in the presence of about 0.1 mmol/l. The fusion of human lymphoma cells was inhibited to 100% at concentrations higher than 0.2 mmol…

Pharmacological preconditioning in global cerebral ischemia

Single dose 3-nitropropionic acid (3-NPA) 24 hr before global ischemia improves neuronal survival in both, neocortex and hippocampus (‘chemical preconditioning’). Neuronal survival after transient global ischemia requires new protein synthesis during recovery, especially of those with anti-apoptotic function. Bcl-2-protein is expressed in neurons that survive cerebral ischemia and may parallel the time course of tolerance after ischemic preconditioning. With this study we examined whether differences in bcl-2-protein expression compared to baseline may be involved in the induction of ischemic tolerance using 3-NPA.

Neurogenic pulmonary oedema after generalized epileptic seizure

The diagnosis 'tonic clonic seizure' is frequently established by emergency physicians on scene. In patients with epilepsy mortality due to accidents, asphyxia, cardiac arrhythmias or postictal neurogenic pulmonary oedema (NPO) is twice as high as in the general population. We report a case of acute pulmonary oedema after a tonic clonic seizure. Following this event, the patient developed respiratory insufficiency and evidence of pulmonary oedema not associated with the classic aetiologies of congestive heart failure, aspiration or toxic exposure. The patient survived the incident after aggressive prehospital treatment, long-term intensive care and subsequent rehabilitation. A systematic ca…

An early bolus of hypertonic saline hydroxyethyl starch improves long-term outcome after global cerebral ischemia.

Objective: The beneficial effect of hypertonic saline solutions in the emergency treatment of shock and traumatic brain injury is well described. The present study determines effects of a single bolus of hypertonic saline on long-term survival, neurologic function, and neuronal survival 10 days after global cerebral ischemia. In addition, we evaluated the therapeutic window for hypertonic saline treatment (early vs. delayed application). Design: Laboratory experiment. Setting: University laboratory. Subjects: Male Wistar rats weighing 240‐330 g. Interventions: Rats were submitted to temporal global cerebral ischemia using temporary bilateral carotid occlusion combined with hypobaric hypoten…

Neurodegeneration in excitotoxicity, global cerebral ischemia, and target deprivation: A perspective on the contributions of apoptosis and necrosis.

In the human brain and spinal cord, neurons degenerate after acute insults (e.g., stroke, cardiac arrest, trauma) and during progressive, adult-onset diseases [e.g., amyotrophic lateral sclerosis, Alzheimer's disease]. Glutamate receptor-mediated excitotoxicity has been implicated in all of these neurological conditions. Nevertheless, effective approaches to prevent or limit neuronal damage in these disorders remain elusive, primarily because of an incomplete understanding of the mechanisms of neuronal death in in vivo settings. Therefore, animal models of neurodegeneration are crucial for improving our understanding of the mechanisms of neuronal death. In this review, we evaluate experimen…

<title>Noninvasive detection of intracerebral hemorrhage using near-infrared spectroscopy (NIRS)</title>

Intracerebral Hemorrhage (IH) is an important cause of secondary brain injury in neurosurgical patients. Early identification and treatment improve neurologic outcome. We have tested Near Infrared Spectroscopy (NIRS) as an alternative noninvasive diagnostic tool compared to CT-Scans to detect IH. We prospectively studied 212 patients with neurologic symptoms associated with intracranial pathology before performing a CT-scan. NIRS signals indicated pathologies in 181 cases (sensitivity 0.96; specificity 0.29). In a subgroup of subdural hematomas NIRS detected 45 of 46 hematomas (sensitivity 0.96; specificity 0.79). Identification of intracerebral hemorrhage using NIRS has the potential to al…

Effects of normobaric oxygen on ciliary beat frequency of human respiratory epithelium

Respiratory infection is a major cause of morbidity after general anaesthesia. Impairment of respiratory ciliary beat frequency (CBF) by different stress factors causes a decrease in mucus transport rate (MTR). We have tested the effect of different concentrations of oxygen on CBF of human respiratory epithelium in a prospective, randomized, in vitro study. Samples of superficial mucosa of the inferior nasal turbinates of 20 non-smoking healthy volunteers were harvested and exposed to three different oxygen environments (group I = 21% oxygen, group II = 60% oxygen and group III = 95% oxygen) for 2 h. In 50% of the samples, exposure time was prolonged. At 30, 60, 90, 120 and 240 min, light m…

Hypoxia-Ischemia in Newborn Piglets Produces Early Defects in Striatal High-Affinity Glutamate Uptake

The antibiotic erythromycin induces tolerance against transient global cerebral ischemia in rats (pharmacologic preconditioning).

Background Cerebral ischemic tolerance can be induced by a variety of noxious stimuli, but no clinically applicable regimen for preconditioning has been described. Therefore, the authors tested the ability of a pharmacologic preconditioning strategy using the well-known macrolide antibiotic erythromycin to induce tolerance against transient global cerebral ischemia in vivo. They also investigated whether tolerance induction by erythromycin involves transcriptional and translational changes of cerebral B-cell leukemia/lymphoma-2 (bcl-2) expression. Methods Male Wistar rats were treated with erythromycin (25 mg/kg intramuscularly) or vehicle and subjected to 15 min of transient global cerebr…

Primery care of the multiply injured child in the emergency room

Publications on paediatric anaesthesia: a quantitative analysis of publication activity and international recognition.

A comprehensive compilation of the current international literature on paediatric anaesthesia is lacking. The aim of this study was to identify all articles on clinical practice in paediatric anaesthesia, to name the respective journals, and to assess the publication activity and international recognition of selected countries for a 6-yr period (1993–1998). The search comprised an article-to-article evaluation (‘hand search') of 12 peer-reviewed anaesthesia journals, as well as an Internet-based (‘SilverPlatter') MedlineTM-search (3.900 medical journals, US National Library of Medicine), both limited to original articles, case reports, reviews and editorials. Selected physical characteristi…

Isoflurane is associated with a similar incidence of emergence agitation/delirium as sevoflurane in young children ? a randomized controlled study

Summary Background:  Children may be agitated or even delirious especially when recovering from general anesthesia using volatile anesthetics. Many trials have focused on the newer agents sevoflurane and desflurane but for the widely used isoflurane little is known about its potential to generate agitation. We investigated the emergence characteristics of small children after sevoflurane or isoflurane with caudal anesthesia for postoperative pain control. Methods:  After institutional approval and parental consent, anesthesia was randomly performed with sevoflurane (n = 30) or isoflurane (n = 29) in children at the age of 3.8 ± 1.8 years during surgical interventions on the lower part of th…

Control of brain temperature during experimental global ischemia in rats.

Temperature control during experimental ischemia continues to be of major interest. However, if exposure of brain tissue is necessary during the experiment, regional heat loss may occur even when the core temperature is maintained. Furthermore, valid non-invasive brain temperature monitoring is difficult in small rodents. This paper describes a method for both monitoring and maintenance of brain temperature during small animal preparations in a stereotaxic frame. The device used includes an ear-bar thermocouple probe and a small near-infrared radiator. The new equipment permitted to maintain peri-ischemic brain temperature at a desired level while carrying out non-invasive continuous record…

Tolerance-Inducing Dose of 3-Nitropropionic Acid Modulates bcl-2 and bax Balance in the Rat Brain: A Potential Mechanism of Chemical Preconditioning

Many studies have reported ischemia protection using various preconditioning techniques, including single dose 3-nitropropionic acid (3-NPA), a mitochondrial toxin. However, the cellular signal transduction cascades resulting in ischemic tolerance and the mechanisms involved in neuronal survival in the tolerant state still remain unclear. The current study investigated the mRNA and protein expression of the antiapoptotic bcl-2 and the proapoptotic bax, two antagonistic members of the bcl-2 gene family, in response to a single dose of 3-NPA, to global cerebral ischemia–reperfusion, and to the combination of both 3-NPA-pretreatment and subsequent global cerebral ischemia–reperfusion. Brain h…

Induction of Cerebral Ischemic Tolerance by Erythromycin Preconditioning Reprograms the Transcriptional Response to Ischemia and Suppresses Inflammation

Background A single dose of the macrolide antibiotic erythromycin can induce tolerance against cerebral ischemia in vivo (pharmacologic preconditioning). This study identified potential mechanisms of tolerance induction by assessing effects of erythromycin preconditioning on the cerebral transcriptional response to transient global cerebral ischemia. Methods Preconditioned and nonpreconditioned rats were exposed to 15 min of global cerebral ischemia, and changes in cerebral gene expression were identified by complementary DNA expression array and quantified by real-time reverse-transcription polymerase chain reaction. Results Ischemia caused a widespread up-regulation of transcription in n…

Failure to Sustain Recovery of Na,K ATPase Function Is a Possible Mechanism for Striatal Neuron Necrosis in Hypoxic-Ischemic Newborn Piglets

Failure to Sustain Recovery of Na,K ATPase Function Is a Possible Mechanism for Striatal Neuron Necrosis in Hypoxic-Ischemic Newborn Piglets

Management of the paediatric airway: new developments

During the last 2 years, some interesting new devices have been made available to improve airway management in children and infants, and several studies have advanced our understanding concerning risks and benefits of the current practice in the field. Certain risk factors for airway related problems during anaesthesia in children having a cold have been identified, and new aspects of the controversy concerning the use of cuffed endotracheal tubes in children presented. Novel video-assisted systems have been introduced for the management of the difficult airway in paediatric patients, and new applications for well known devices have been suggested, such as the laryngeal mask airway serving …

Quantitative EEG during Early Recovery from Hypoxic-Ischemic Injury in Immature Piglets: Burst Occurrence and Duration

This study examined the course of EEG recovery in an animal model of hypoxic-ischemic injury. The model used periods of hypoxia, room air and asphyxia to induce cardiac arrest. One-week-old piglets (n = 16) were exposed to a period of hypoxia, room air and complete asphyxia for 7 minutes. After cardiac arrest and resuscitation, two EEG features were evaluated as prognostic indicators of behavioral outcome as assessed by a neuroscore at 24 hours after insult. A prominent EEG feature was the number and duration of bursts evident during recovery. Episodes of bursting were detected through the thresholds on sustained periods of elevated power. After the animal was resuscitated, the EEG was moni…