Articles: closed-circuit-anesthesia.
-
J Clin Monit Comput · Aug 2020
Behavior of a dual closed-loop controller of propofol and remifentanil guided by the bispectral index for postoperative sedation of adult cardiac surgery patients: a preliminary open study.
A dual-loop controller permits the automated titration of propofol and remifentanil during anesthesia; it has never been used in intensive care after cardiac surgery. The goal of this preliminary study was to determine the efficacy of this controller to provide postoperative sedation in 19 adult cardiac surgery patients with a Bispectral Index target of 50. Results are presented as numbers (percentages) or medians [25th-75th percentiles]. ⋯ Automated sedation device was discontinued in two patients for hemodynamic instability. No patient had awareness of the postoperative sedation period. Dual closed-loop can provide postoperative sedation after cardiac surgery but the choice of the depth of sedation should take into account the risk of hypotension.
-
Anesthesia and analgesia · Jun 2020
Observational StudyInfluence of Remifentanil on the Control Performance of the Bispectral Index Controlled Bayesian-Based Closed-Loop System for Propofol Administration.
Remifentanil does not reduce the performance of BIS-based closed-loop propofol anesthesia with a remifentanil effect site concentration of 2.8-7.5 ng/mL.
pearl -
This article examines successful management of an anesthesia machine failure with the Draeger (or Dräger) Apollo (Draeger Inc) anesthesia workstation. Approximately 45 minutes into the case, while the patient was under general anesthesia and mechanical ventilation, the anesthesia machine failed to achieve positive pressurization following a high-pressure alarm. Despite multiple maneuvers, the issue did not resolve until the machine was manually powered off and on at the main power switch. This case report emphasizes the importance of always having a backup means of patient ventilation and anesthesia administration.
-
Anesthesia and analgesia · Feb 2020
Estimating the Impact of Carbon Dioxide Absorbent Performance Differences on Absorbent Cost During Low-Flow Anesthesia.
Reducing fresh gas flow when using a circle anesthesia circuit is the most effective strategy for reducing both inhaled anesthetic vapor cost and waste. As fresh gas flow is reduced, the amount of exhaled gas rebreathed increases, but the utilization of carbon dioxide absorbent increases as well. Reducing fresh gas flow may not make economic sense if the increased cost of absorbent utilization exceeds the reduced cost of anesthetic vapor. The primary objective of this study was to determine the minimum fresh gas flow at which absorbent costs do not exceed vapor savings. Another objective is to provide a qualitative insight into the factors that influence absorbent performance as fresh gas flow is reduced. ⋯ The relative costs of anesthetic vapor and carbon dioxide absorbent as fresh gas flow is reduced are dependent on choice of anesthetic vapor and performance of the carbon dioxide absorbent. Absorbent performance is determined by the product selected and strategy for replacement. Clinicians can maximize the performance of absorbents by replacing them based on the appearance of inspired carbon dioxide rather than the indicator. Even though absorbent costs exceed vapor savings as fresh gas flow is reduced, isoflurane is still the lowest cost choice for the environmentally sound practice of closed-circuit anesthesia.
-
Minerva anestesiologica · Jan 2020
Meta AnalysisHemodynamic stability of closed-loop anesthesia systems: a systematic review.
This systematic review investigates the effect of closed-loop anesthesia delivery on the maintenance of cardiovascular parameters. The specific challenges arise from the fact that many physiological variables used for the control of anesthetic delivery and maintenance of hemodynamic stability are regulated by the autonomic nervous system, which is subject to high inter-individual variability. ⋯ The findings support the use of closed-loop systems for anesthetic delivery. Interpretation should take into account limitations, such as the large variations in the selected studies in the type of parameters used to measure outcomes. In summary, this review provides evidence supporting the importance of considering cardiovascular variables in the design of automated anesthetic delivery systems.