Postoperative neurocognitive disorders in ambulatory surgery: a narrative review.

Postoperative neurocognitive disorders (PoNCDs), such as postoperative delirium and cognitive dysfunction or decline can occur after surgery, especially in older patients. This significantly affects patient morbidity and surgical outcomes. Among various risk factors, recent studies have shown that preoperative frailty is associated with developing these conditions.

Current clinical application of dantrolene sodium.

Dantrolene sodium (DS) was first introduced as an oral antispasmodic drug. However, in 1975, DS was demonstrated to be effective for managing malignant hyperthermia (MH) and was adopted as the primary therapeutic drug after intravenous administration. However, it is difficult to administer DS intravenously to manage MH.

Chronic exposure to dexamethasone may not affect sugammadex reversal of rocuronium-induced neuromuscular blockade: an in vivo study on rats.

Background: Chronic glucocorticoid exposure is associated with resistance to nondepolarizing neuromuscular blocking agents. Therefore, we hypothesized that sugammadex-induced recovery would occur more rapidly in subjects exposed to chronic dexamethasone compared to those who were not exposed. This study evaluated the sugammadex-induced recovery profile after neuromuscular blockade (NMB) in rats exposed to chronic dexamethasone.

Effects of hydrocortisone-presensitized sugammadex on recovery from neuromuscular blockade induced by rocuronium: a rodent in vivo study.

Background: Sugammadex is a specific antagonist of aminosteroidal neuromuscular blocking agents with 1:1 binding to guest molecules. Sugammadex can also bind to other drugs having a steroid component in its chemical structure. In this in vivo experiment, we investigated the differences in the recovery of rocuronium-induced neuromuscular blockade using sugammadex pre-exposed with two different concentrations of hydrocortisone.

The principles of presenting statistical results using figures.

Tables and figures are commonly adopted methods for presenting specific data or statistical analysis results. Figures can be used to display characteristics and distributions of data, allowing for intuitive understanding through visualization and thus making it easier to interpret the statistical results. To maximize the positive aspects of figure presentation and increase the accuracy of the content, in this article, the authors will describe how to choose an appropriate figure type and the necessary components to include.

Considerations for crossover design in clinical study.

This article introduces a crossover design that is often used in clinical studies, with the advantage of comparing treatment effects within one study subject. In particular, the advantages and disadvantages of the two-period, two-sequence crossover design (2 × 2 or AB/BA crossover design), which is widely used in clinical practice, are identified, and the elements necessary for analysis are introduced. This article explains the carryover effect, period effect, sequence effect, and period-by-treatment interaction in a crossover design and examines the analysis commands of SAS along with example data.

Effects of sevoflurane and adenosine receptor antagonist on the sugammadex-induced recovery from rocuronium-induced neuromuscular blockade in rodent phrenic nerve-hemidiaphragm tissue specimens.

Sevoflurane affects on the A1 receptor in the central nervous system and potentiates the action of neuromuscular blocking agents. In the present study, we investigated whether sevoflurane (SEVO) has the ability to potentiate the neuromuscular blocking effect of rocuronium and if the specific antagonist of adenosine receptor (SLV320) can reverse this effect. In this study, phrenic nerve-hemidiaphragm tissue specimens were obtained from 40 Sprague-Dawley (SD) rats.

The principles of presenting statistical results: Table.

General medical journals such as the Korean Journal of Anesthesiology (KJA) receive numerous manuscripts every year. However, reviewers have noticed that the tables presented in various manuscripts have great diversity in their appearance, resulting in difficulties in the review and publication process. It might be due to the lack of clear written instructions regarding reporting of statistical results for authors.

Does the minimal occlusive volume technique provide adequate endotracheal tube cuff pressure to prevent air leakage?: a prospective, randomized, crossover clinical study.

Background: Methods of determining proper endotracheal tube (ETT) cuff pressure to prevent air leakage include the minimal occlusive volume (MOV) technique, which uses auscultation, and the spirometer technique, which directly measures inspiratory and expiratory breathing volumes. Spirometers may measure even small air leakage, therefore, the spirometer technique requires a higher cuff pressure than the MOV technique to completely seal the airway. This study aimed to evaluate the difference in cuff pressure between the two techniques used to seal the airway.

Tips for troublesome sample-size calculation.

Properly set sample size is one of the important factors for scientific and persuasive research. The sample size that can guarantee both clinically significant differences and adequate power in the phenomena of interest to the investigator, without causing excessive financial or medical considerations, will always be the object of concern. In this paper, we reviewed the essential factors for sample size calculation.

Effects of different sugammadex doses on the train of four ratio recovery progression during rocuronium induced neuromuscular blockade in the rat phrenic nerve hemidiaphragm.

Background: In this study, we used an ex-vivo model to investigate the recovery pattern of both the train-of-four (TOF) ratio and first twitch tension of TOF (T1), and determined their relationship during recovery from rocuronium-induced neuromuscular blockade at various concentrations of sugammadex.

Methods: Tissue specimens of the phrenic nerve-hemidiaphragm were obtained from 60 adult Sprague-Dawley rats. Each specimen was immersed in an organ bath filled with Krebs buffer solution and stimulated with the TOF pattern using indirect supramaximal stimulation at 20-second intervals.

Effect of protracted dexamethasone exposure and its withdrawal on rocuronium-induced neuromuscular blockade and sugammadex reversal: an ex vivo rat study.

Studies have reported that protracted dexamethasone treatment induces resistance to nondepolarizing neuromuscular blocking agents (NMBAs) and the association with nicotinic acetylcholine receptors in the diaphragm of rats. Here, we investigated the effect of protracted dexamethasone administration on the sensitivity to rocuronium and the recovery profile when reversed by sugammadex; additionally, we observed the recovery period of pharmacodynamic change after withdrawal. Sprague-Dawley rats received daily intraperitoneal injections of dexamethasone or saline for 14 days.

Survival analysis: part II - applied clinical data analysis.

As a follow-up to a previous article, this review provides several in-depth concepts regarding a survival analysis. Also, several codes for specific survival analysis are listed to enhance the understanding of such an analysis and to provide an applicable survival analysis method. A proportional hazard assumption is an important concept in survival analysis.

Randomization in clinical studies.

Randomized controlled trial is widely accepted as the best design for evaluating the efficacy of a new treatment because of the advantages of randomization (random allocation). Randomization eliminates accidental bias, including selection bias, and provides a base for allowing the use of probability theory. Despite its importance, randomization has not been properly understood.

Effects of dexamethasone and hydrocortisone on rocuroniuminduced neuromuscular blockade and reversal by sugammadex in phrenic nerve-hemidiaphragm rat model.

Background: The facilitator effects of steroids on neuromuscular transmission may cause resistance to neuromuscular blocking agents. Additionally, steroids may hinder sugammadex reversal of neuromuscular blockade, but these findings remain controversial. Therefore, we explored the effect of dexamethasone and hydrocortisone on rocuronium-induced neuromuscular blockade and their inhibitory effect on sugammadex.

Assessment of P values for demographic data in randomized controlled trials.

In a large number of randomized controlled trials, researchers provide P values for demographic data, which are commonly reported in table 1 of the article for the purpose of emphasizing the lack of differences between or among groups. As such, the authors intend to demonstrate that statistically insignificant P values in the demographic data confirm that group randomization was adequately performed. However, statistically insignificant P values do not necessarily reflect successful randomization.

Dexamethasone concentration affecting rocuronium-induced neuromuscular blockade and sugammadex reversal in a rat phrenic nerve-hemidiaphragm model: An ex vivo study.

Background: The concentration range of dexamethasone that inhibits neuromuscular blockade (NMB) and sugammadex reversal remains unclear.

Objective: To evaluate the effects of dexamethasone on rocuronium-induced NMB and sugammadex reversal.

Design: Ex vivo study.

Effects of neuromuscular presynaptic muscarinic M receptor blockade on rocuronium-induced neuromuscular blockade in immobilized tibialis anterior muscles.

This in vivo study tested the hypothesis that the modulation of acetylcholine (ACh) release by the M muscarinic receptor (mAChR) in the neuromuscular junction of disused muscles may affect the tensions of the muscles during the neuromuscular monitoring of a rocuronium-induced neuromuscular block and compared the results with those obtained from normal muscles. A total of 20 C57BL/6 (wild-type) and 10 α7 knock out (α7KO) mice were used in this experiment. As a pre-experimental procedure, knee and ankle joints of right hind limbs were fixed by needle pinning at the 90° flexed position.

Survival analysis: Part I - analysis of time-to-event.

Length of time is a variable often encountered during data analysis. Survival analysis provides simple, intuitive results concerning time-to-event for events of interest, which are not confined to death. This review introduces methods of analyzing time-to-event.