Effect of the Mode of Administration of Inhaled Anaesthetics on the Interpretation of the F<sub>A</sub>/F<sub>I</sub> Curve – a GasMan® Simulation

Zundert, Tom Van; Hendrickx, Jan F. A.; Brebels, A.; Cooman, Sofie De; Gatt, Stephen; Wolf, A. De

doi:10.1177/0310057x1003800114

Cited by 12 publications

(6 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…10 h) are limited and there are no clinical investigations comparing the recovery of obese and morbidly obese patients after longer durations of volatile anesthesia. Further, Table 3 Awakening times for desflurane, sevoflurane and isoflurane after a duration of anesthesia of 1, 5 and 10 h for the four different simulation models Decrement times are displayed in min:s. Since one simulation model only has one decrement time for one specific volatile agent and duration of administration, no further statistical analysis can be performed [5] and sevoflurane group 41 [6] kg m 2 ) after volatile anesthesia combined with a target controlled infusion of remifentanil (duration of administration in desflurane group of 112 [28] and sevoflurane group 112 [33] minutes) after laparoscopic gastric banding [42]. In this clinical investigation, postoperative recovery was assessed with the Aldrete score [43].…”

Section: Discussionmentioning

confidence: 99%

“…The theoretical model is able to reproduce the kinetic relationships described by Kety and explored by Eger [12,26,31,32]. Furthermore, the Gas Man simulation model has been used extensively in pharmacokinetic studies to investigate the uptake, distribution and elimination of volatile anesthetics during different clinical settings [25,27,33,34].…”

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

Context-sensitive decrement times for inhaled anesthetics in obese patients explored with Gas Man®

Weber

Schmidt

Wirth

et al. 2020

J Clin Monit Comput

View full text Add to dashboard Cite

Anesthesia care providers and anesthesia decision support tools use mathematical pharmacokinetic models to control delivery and especially removal of anesthetics from the patient's body. However, these models are not able to reflect alterations in pharmacokinetics of volatile anesthetics caused by obesity. The primary aim of this study was to refine those models for obese patients. To investigate the effects of obesity on the elimination of desflurane, isoflurane and sevoflurane for various anesthesia durations, the Gas Man® computer simulation software was used. Four different models simulating patients with weights of 70 kg, 100 kg, 125 kg and 150 kg were constructed by increasing fat weight to the standard 70 kg model. For each modelled patient condition, the vaporizer was set to reach quickly and then maintain an alveolar concentration of 1.0 minimum alveolar concentration (MAC). Subsequently, the circuit was switched to an open (non-rebreathing) circuit model, the inspiratory anesthetic concentration was set to 0 and the time to the anesthetic decrements by 67% (awakening times), 90% (recovery times) and 95% (resolution times) in the vessel-rich tissue compartment including highly perfused tissue of the central nervous system were determined. Awakening times did not differ greatly between the simulation models. After volatile anesthesia with sevoflurane and isoflurane, awakening times were lower in the more obese simulation models. With increasing obesity, recovery and resolution times were higher. The additional adipose tissue in obese simulation models did not prolong awakening times and thus may act more like a sink for volatile anesthetics. The results of these simulations should be validated by comparing the elimination of volatile anesthetics in obese patients with data from our simulation models.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

Context-sensitive decrement times for inhaled anesthetics in obese patients explored with Gas Man®

Weber

Schmidt

Wirth

et al. 2020

J Clin Monit Comput

View full text Add to dashboard Cite

show abstract

“…Once inspired and end-tidal sevoflurane concentration equilibrated at a predetermined target concentration, these settings were maintained for 6 minutes to equilibrate sevoflurane concentration between the blood and brain. [ 11 , 12 ] The child was then positioned, and localization of the target muscle using a nerve stimulator for botulinum toxin injection was attempted.…”

Section: Methodsmentioning

confidence: 99%

50% effective concentration of sevoflurane for immobility in cerebral palsy children undergoing botulinum toxin injection

et al. 2022

View full text Add to dashboard Cite

Background: This prospective study aimed to determine the optimum end-tidal sevoflurane concentration required for immobility during botulinum toxin injection in spontaneously breathing children with cerebral palsy (CP). Methods: Twenty-three children with spastic CP, aged 3 to 12 years, with American Society of Anesthesiologists (ASA) physical status I and II, scheduled to receive botulinum toxin type A injection were enrolled in the study. After induction of deep sedation using pre-filled 8% sevoflurane in oxygen and maintenance of the predetermined end-tidal sevoflurane concentration, the botulinum toxin was injected in spontaneously breathing children. The response to the botulinum toxin injection was classified as “movement” or “no movement” by an independent investigator who was blinded to the predetermined end-tidal sevoflurane concentration and bispectral index (BIS) value. The end-tidal sevoflurane concentration was predetermined, initiating at 2.0% with 0.2% as a step size in the next patient depending on the previous patient’s response using the modified Dixon’s up-and-down method. Results: Of 21 children, 12 (57.1%) showed “no movement” in response to the botulinum toxin injection. By Dixon’s up-and-down method, the 50% effective end-tidal concentration (EC 50 ) of sevoflurane for successful botulinum toxin injection was 1.76 ± 0.15% (95% CI 1.62–1.90). Based on the dose‐response curve using probit analysis, the predicted EC 50 and 95% effective end-tidal concentrations (EC 95 ) of sevoflurane without movement were 1.77% (95% CI 1.59–2.35) and 2.09% (95% CI 1.89–5.80), respectively. Conclusion: Botulinum toxin injection can be successfully accomplished at an end-tidal sevoflurane concentration of 1.76 ± 0.15% in 50% of spontaneously breathing children with CP aged 3–12 years.

show abstract

“…The pharmacokinetic profile of inhaled anesthetics is also well known and has been included in simulation software such as "GasMan" [6], although interactions with other drugs aren't implemented there. However, to my knowledge appropriate algorithms for all possible interactions with these drugs…”

Section: Insert Fig 2 Herementioning

confidence: 99%

A plea for an independent holistic anaesthesia delivery system

Bíró

2013

European Journal of Anaesthesiology

View full text Add to dashboard Cite

Effect of the Mode of Administration of Inhaled Anaesthetics on the Interpretation of the F_A/F_I Curve – a GasMan® Simulation

Cited by 12 publications

References 6 publications

Context-sensitive decrement times for inhaled anesthetics in obese patients explored with Gas Man®

Context-sensitive decrement times for inhaled anesthetics in obese patients explored with Gas Man®

50% effective concentration of sevoflurane for immobility in cerebral palsy children undergoing botulinum toxin injection

A plea for an independent holistic anaesthesia delivery system

Contact Info

Product

Resources

About

Effect of the Mode of Administration of Inhaled Anaesthetics on the Interpretation of the FA/FI Curve – a GasMan® Simulation

Cited by 12 publications

References 6 publications

Context-sensitive decrement times for inhaled anesthetics in obese patients explored with Gas Man®

Context-sensitive decrement times for inhaled anesthetics in obese patients explored with Gas Man®

50% effective concentration of sevoflurane for immobility in cerebral palsy children undergoing botulinum toxin injection

A plea for an independent holistic anaesthesia delivery system

Contact Info

Product

Resources

About

Effect of the Mode of Administration of Inhaled Anaesthetics on the Interpretation of the F_A/F_I Curve – a GasMan® Simulation