leo booij - Academia.edu (original) (raw)
Papers by leo booij
Medical news of the North Caucasus, 2017
In a review of the current literature assesses the recently discovered phenomenon and the toxicit... more In a review of the current literature assesses the recently discovered phenomenon and the toxicity of anesthetics in the developing child brain. The ways of diagnostics of morphological and functional abnormalities of brain activity in children. Provides indisputable data on the possibility of this type of interactions taking into account the mechanism of action of anesthetics. Comparative characteristics of strength toxic effects on children’s brain different types of inhalation and non-inhalation anesthetics. There is a comparison of the degree of toxic impact on the brain at single and repeated exposure of anesthesia. Emphasizes the lack of information and especially objective data visualization of degenerative changes in children’s brain due to ethical constraints and the impossibility of obtaining samples for biopsy. The conclusion about the appropriateness of expectant surgical tactics in the absence of urgent indications for surgical intervention to 4 years of a child’s life....
In this short review are the physiological processes involved in neuromuscular transmission descr... more In this short review are the physiological processes involved in neuromuscular transmission described. Muscle relaxants are used in clinical anaesthesia to block this transmission and the requirements for an ideal drug are defined. The disadvantages of the currently available drugs are summarized including those for succinylcholine. Some focus is placed on rocuronium. The main disadvantage, i.e. residual paralysis, can be treated and/or prevented by reversal of such a block. However, currently used compounds have serious adverse effects and are not always efficacious. Therefore also the requirements for an ideal reversal agent are defined. Against this profile is sugammadex discussed. The possibility to replace succinylcholine with a combination of succinylcholine and sugammadex is discussed.
Anaesthesia in children with a neuromuscular disease is challenging the anaesthesiologist. In thi... more Anaesthesia in children with a neuromuscular disease is challenging the anaesthesiologist. In this group occur frequently perioperative complications from muscle weakness, respiratory depression and cardiac involvement. Lack of experience is the reason for uncertainty. Knowledge of the pathophysiology and relevant pharmacology of the disease, preoperative development of an adequate treatment plan with consultation of other disciplines, and close monitoring of the patient are extremely important. The various diseases can be divided according to the location of the disorder: pre-junctional, junctional, post-junctional. Many of them are described in this article. Only few patients are susceptible for malignant hyperthermia. Rhabdomyolyis can be induced by inhalational anaesthesia and succinylcholine in many of these diseases, whereas in most a prolonged effect of muscle relaxants exist and succinylcholine may induce myotonic reactions. The complications and anaesthetic effects in many ...
Medical news of the North Caucasus
Current Anaesthesia & Critical Care
Current Anaesthesia & Critical Care
The availability of organs for transplantation is very limited. It is not only the legal and ethi... more The availability of organs for transplantation is very limited. It is not only the legal and ethical factors, but also the feelings of the relatives of potential donors that contribute to this scarcity. All involved in the acquisition of organs must be aware of the regulations and the proper way to determine brain death. Furthermore, anaesthesiologists need to know about the problems that may occur during conservation and harvesting of organs. All these issues are dealt with in the article presented here.
Current Anaesthesia & Critical Care
Survey of Anesthesiology, 1984
Survey of Anesthesiology, 1980
Antagonism by neostigmine of neuromuscular blockade produced by pancuronium or its metabolites wa... more Antagonism by neostigmine of neuromuscular blockade produced by pancuronium or its metabolites was studied in the cat anterior or tibialis muscle-peroneal nerve preparation using constant infusions of muscle relaxants. The ED50 of neostigmine (dose which caused a 50% antagonism) was 16, 11, 29, and 26 micrograms/kg for pancuronium, 3-hydroxypancuronium, 17-hydroxypancuronium, and 3, 17-hydroxypancuronium, respectively. Times of onset of neostigmine action were shorter when antagonizing 17-hydroxypancuronium neuromuscular blockade. Duration of neostigmine action when antagonizing 17- or 3, 17-hydroxypancuronium blockade was shorter than with pancuronium or 3-hydroxypancuronium. We conclude that more neostigmine is required to antagonize 17- or 3,17-hydroxypancuronium neuromuscular blockade than is required to antagonize pancuronium. Conversely, less neostigmine was required to antagonize 3-hydroxypancuronium blockade.
Curr Opin Anesthesiol, 1989
Baillière's Clinical Anaesthesiology, 1994
Muscle contraction is initiated when acetylcholine is bound to postsynaptic acetylcholine recepto... more Muscle contraction is initiated when acetylcholine is bound to postsynaptic acetylcholine receptors at the neuromuscular junction. Such binding starts to be ineffective either when 25% or more of the receptors are occupied by depolarizing muscle relaxants, or when 70-75% or more receptors are occupied by non-depolarizing muscle relaxants. Therefore the concentration of such relaxants at the receptor, i.e. in the biophase, is of the utmost importance for their clinical effect (pharmacodynamics). The concentration at the biophase is in equilibrium with the plasma concentration, which in turn depends on the dose of relaxant administered, and on the pharmacokinetic behaviour of that individual drug. Hence, as with many other drugs, a relationship exists between plasma concentration of muscle relaxant and the degree of paralysis. The pharmacokinetic behaviour of muscle relaxants thus determines the clinical effect to a considerable extent (Shanks et al, 1978; Stanski and Sheiner, 1979). The relationship between plasma concentration and effect is described by the Hill equation (1), in which there is no further increase in effect beyond a certain concentration: f= Cs/(c ~ + ECsoO [1] Wherefis the intensity of effect, C is the plasma concentration, ECs0 is the plasma concentration at 50% effect and s is the Hill exponent. The time course of action of non-depolarizing muscle relaxants is thus a reflection of the plasma concentration decay curve. Concentration decay curves are characterized by a number of parameters (slopes, intercepts, etc.) from which the pharmacokinetic variables (half-life times, plasma clearance, volumes of distribution, etc.) can be calculated. GENERAL ASPECTS OF THE PHARMACOKINETICS OF RELAXANTS All muscle relaxants contain quaternary ammonium groups, and are thereby positively charged at body temperature. Because of this ionization they are highly water-soluble and relatively insoluble in fat. They are therefore poorly absorbed from the gut. Their onset of effect is delayed when administered intramuscularly, although the actual absorption rate is dependant on the site of intramuscular administration (Iwasaki et al, 1992).
Pharm World Sci, 1997
Page 1. 3.1.Introduction Sometimes muscle relaxant is needed for a long peri-od of time, ie in th... more Page 1. 3.1.Introduction Sometimes muscle relaxant is needed for a long peri-od of time, ie in the ICU. In other cases a constant depression of muscle contraction is necessary during anaesthesia. Such constant blockades are ...
Current Anaesthesia & Critical Care, 1996
Niets uit deze uitgave mag worden vermenigvuldigd en/of openbaar worden gemaakt middels druk, fot... more Niets uit deze uitgave mag worden vermenigvuldigd en/of openbaar worden gemaakt middels druk, fotokopie, microfilm, geluidsband of op welke andere wijze dan ook, zonder voorafgaande schriftelijke toestemming van de copyrighthouder.
Nederlands tijdschrift voor geneeskunde
Acta anaesthesiologica Belgica
ABSTRACT
Medical news of the North Caucasus, 2017
In a review of the current literature assesses the recently discovered phenomenon and the toxicit... more In a review of the current literature assesses the recently discovered phenomenon and the toxicity of anesthetics in the developing child brain. The ways of diagnostics of morphological and functional abnormalities of brain activity in children. Provides indisputable data on the possibility of this type of interactions taking into account the mechanism of action of anesthetics. Comparative characteristics of strength toxic effects on children’s brain different types of inhalation and non-inhalation anesthetics. There is a comparison of the degree of toxic impact on the brain at single and repeated exposure of anesthesia. Emphasizes the lack of information and especially objective data visualization of degenerative changes in children’s brain due to ethical constraints and the impossibility of obtaining samples for biopsy. The conclusion about the appropriateness of expectant surgical tactics in the absence of urgent indications for surgical intervention to 4 years of a child’s life....
In this short review are the physiological processes involved in neuromuscular transmission descr... more In this short review are the physiological processes involved in neuromuscular transmission described. Muscle relaxants are used in clinical anaesthesia to block this transmission and the requirements for an ideal drug are defined. The disadvantages of the currently available drugs are summarized including those for succinylcholine. Some focus is placed on rocuronium. The main disadvantage, i.e. residual paralysis, can be treated and/or prevented by reversal of such a block. However, currently used compounds have serious adverse effects and are not always efficacious. Therefore also the requirements for an ideal reversal agent are defined. Against this profile is sugammadex discussed. The possibility to replace succinylcholine with a combination of succinylcholine and sugammadex is discussed.
Anaesthesia in children with a neuromuscular disease is challenging the anaesthesiologist. In thi... more Anaesthesia in children with a neuromuscular disease is challenging the anaesthesiologist. In this group occur frequently perioperative complications from muscle weakness, respiratory depression and cardiac involvement. Lack of experience is the reason for uncertainty. Knowledge of the pathophysiology and relevant pharmacology of the disease, preoperative development of an adequate treatment plan with consultation of other disciplines, and close monitoring of the patient are extremely important. The various diseases can be divided according to the location of the disorder: pre-junctional, junctional, post-junctional. Many of them are described in this article. Only few patients are susceptible for malignant hyperthermia. Rhabdomyolyis can be induced by inhalational anaesthesia and succinylcholine in many of these diseases, whereas in most a prolonged effect of muscle relaxants exist and succinylcholine may induce myotonic reactions. The complications and anaesthetic effects in many ...
Medical news of the North Caucasus
Current Anaesthesia & Critical Care
Current Anaesthesia & Critical Care
The availability of organs for transplantation is very limited. It is not only the legal and ethi... more The availability of organs for transplantation is very limited. It is not only the legal and ethical factors, but also the feelings of the relatives of potential donors that contribute to this scarcity. All involved in the acquisition of organs must be aware of the regulations and the proper way to determine brain death. Furthermore, anaesthesiologists need to know about the problems that may occur during conservation and harvesting of organs. All these issues are dealt with in the article presented here.
Current Anaesthesia & Critical Care
Survey of Anesthesiology, 1984
Survey of Anesthesiology, 1980
Antagonism by neostigmine of neuromuscular blockade produced by pancuronium or its metabolites wa... more Antagonism by neostigmine of neuromuscular blockade produced by pancuronium or its metabolites was studied in the cat anterior or tibialis muscle-peroneal nerve preparation using constant infusions of muscle relaxants. The ED50 of neostigmine (dose which caused a 50% antagonism) was 16, 11, 29, and 26 micrograms/kg for pancuronium, 3-hydroxypancuronium, 17-hydroxypancuronium, and 3, 17-hydroxypancuronium, respectively. Times of onset of neostigmine action were shorter when antagonizing 17-hydroxypancuronium neuromuscular blockade. Duration of neostigmine action when antagonizing 17- or 3, 17-hydroxypancuronium blockade was shorter than with pancuronium or 3-hydroxypancuronium. We conclude that more neostigmine is required to antagonize 17- or 3,17-hydroxypancuronium neuromuscular blockade than is required to antagonize pancuronium. Conversely, less neostigmine was required to antagonize 3-hydroxypancuronium blockade.
Curr Opin Anesthesiol, 1989
Baillière's Clinical Anaesthesiology, 1994
Muscle contraction is initiated when acetylcholine is bound to postsynaptic acetylcholine recepto... more Muscle contraction is initiated when acetylcholine is bound to postsynaptic acetylcholine receptors at the neuromuscular junction. Such binding starts to be ineffective either when 25% or more of the receptors are occupied by depolarizing muscle relaxants, or when 70-75% or more receptors are occupied by non-depolarizing muscle relaxants. Therefore the concentration of such relaxants at the receptor, i.e. in the biophase, is of the utmost importance for their clinical effect (pharmacodynamics). The concentration at the biophase is in equilibrium with the plasma concentration, which in turn depends on the dose of relaxant administered, and on the pharmacokinetic behaviour of that individual drug. Hence, as with many other drugs, a relationship exists between plasma concentration of muscle relaxant and the degree of paralysis. The pharmacokinetic behaviour of muscle relaxants thus determines the clinical effect to a considerable extent (Shanks et al, 1978; Stanski and Sheiner, 1979). The relationship between plasma concentration and effect is described by the Hill equation (1), in which there is no further increase in effect beyond a certain concentration: f= Cs/(c ~ + ECsoO [1] Wherefis the intensity of effect, C is the plasma concentration, ECs0 is the plasma concentration at 50% effect and s is the Hill exponent. The time course of action of non-depolarizing muscle relaxants is thus a reflection of the plasma concentration decay curve. Concentration decay curves are characterized by a number of parameters (slopes, intercepts, etc.) from which the pharmacokinetic variables (half-life times, plasma clearance, volumes of distribution, etc.) can be calculated. GENERAL ASPECTS OF THE PHARMACOKINETICS OF RELAXANTS All muscle relaxants contain quaternary ammonium groups, and are thereby positively charged at body temperature. Because of this ionization they are highly water-soluble and relatively insoluble in fat. They are therefore poorly absorbed from the gut. Their onset of effect is delayed when administered intramuscularly, although the actual absorption rate is dependant on the site of intramuscular administration (Iwasaki et al, 1992).
Pharm World Sci, 1997
Page 1. 3.1.Introduction Sometimes muscle relaxant is needed for a long peri-od of time, ie in th... more Page 1. 3.1.Introduction Sometimes muscle relaxant is needed for a long peri-od of time, ie in the ICU. In other cases a constant depression of muscle contraction is necessary during anaesthesia. Such constant blockades are ...
Current Anaesthesia & Critical Care, 1996
Niets uit deze uitgave mag worden vermenigvuldigd en/of openbaar worden gemaakt middels druk, fot... more Niets uit deze uitgave mag worden vermenigvuldigd en/of openbaar worden gemaakt middels druk, fotokopie, microfilm, geluidsband of op welke andere wijze dan ook, zonder voorafgaande schriftelijke toestemming van de copyrighthouder.
Nederlands tijdschrift voor geneeskunde
Acta anaesthesiologica Belgica
ABSTRACT