Publications by authors named "Seung Woo Ku"

Article Synopsis
  • Efficient operating room (OR) scheduling can enhance utilization and lower costs, particularly when managed by a dedicated scheduling office (ORSO).
  • A study at a tertiary hospital analyzed data from two years and showed significant improvements in OR utilization rates, daily case numbers, and cumulative operation time after scheduling process adjustments were made.
  • Increased efficiencies were observed during regular hours, while evening/night time operations decreased, suggesting that a well-coordinated scheduling office can optimize OR management, leading to financial and operational benefits.
View Article and Find Full Text PDF

Background: Laryngeal microsurgery (LMS) is often accompanied by a sudden increase in blood pressure (BP) during surgery because of stimulation around the larynx. This sudden change in the hemodynamic status is not immediately reflected in a casual cuff-type measurement that takes intermittent readings every 3 to 5 min.

Objective: This study aimed to investigate the potential of pulse arrival time (PAT) as a marker for a BP surge, which usually occurs in patients undergoing LMS.

View Article and Find Full Text PDF

A 57-year-old woman scheduled for cochlear implant removal exhibited preoperative electrocardiographic findings of early repolarization (ER). Four episodes of transient ST segment elevations during surgery raised suspicion for vasospastic angina (VA). In the post-anesthetic care unit, the patient complained of chest discomfort and received sublingual nitroglycerin with uncertain effect.

View Article and Find Full Text PDF

We report a case of pulmonary aspiration during induction of general anesthesia in a patient who was status post esophagectomy. Sudden, unexpected aspiration occurred even though the patient had fasted adequately (over 13 hours) and received rapid sequence anesthesia induction. Since during esophagectomy, the lower esophageal sphincter is excised, stomach vagal innervation is lost, and the stomach is flaccid, draining only by gravity, the patient becomes vulnerable to aspiration.

View Article and Find Full Text PDF

Ketamine and propofol have distinctively different molecular mechanisms of action and neurophysiological features, although both induce loss of consciousness. Therefore, identifying a common feature of ketamine- and propofol-induced unconsciousness would provide insight into the underlying mechanism of losing consciousness. In this study we search for a common feature by applying the concept of type-II complexity, and argue that neural complexity is essential for a brain to maintain consciousness.

View Article and Find Full Text PDF

Recent studies of propofol-induced unconsciousness have identified characteristic properties of electroencephalographic alpha rhythms that may be mediated by drug activity at γ-aminobutyric acid (GABA) receptors in the thalamus. However, the effect of ketamine (a primarily non-GABAergic anesthetic drug) on alpha oscillations has not been systematically evaluated. We analyzed the electroencephalogram of 28 surgical patients during consciousness and ketamine-induced unconsciousness with a focus on frontal power, frontal cross-frequency coupling, frontal-parietal functional connectivity (measured by coherence and phase lag index), and frontal-to-parietal directional connectivity (measured by directed phase lag index) in the alpha bandwidth.

View Article and Find Full Text PDF

Ethanol sclerotherapy for the treatment of low-flow vascular malformations can cause catastrophic cardiopulmonary complications, including pulmonary embolism and pulmonary hypertension, that can result in right heart failure and fatal arrhythmias, leading to death. We here report a case of abrupt cardiovascular collapse that developed immediately following ethanol sclerotherapy in 31-year-old female patient who had a large arteriovenous malformation in her leg. Anesthesiologists should be aware of the fatal cardiopulmonary complications that are associated with ethanol sclerotherapy and consider the use of invasive hemodynamic monitoring, such as pulmonary artery pressure monitoring, when large doses of ethanol are required.

View Article and Find Full Text PDF

Introduction: Directional connectivity from anterior to posterior brain regions (or "feedback" connectivity) has been shown to be inhibited by propofol and sevoflurane. In this study the authors tested the hypothesis that ketamine would also inhibit cortical feedback connectivity in frontoparietal networks.

Methods: Surgical patients (n = 30) were recruited for induction of anesthesia with intravenous ketamine (2 mg/kg); electroencephalography of the frontal and parietal regions was acquired.

View Article and Find Full Text PDF

Background: The precise mechanism and optimal measure of anesthetic-induced unconsciousness has yet to be elucidated. Preferential inhibition of feedback connectivity from frontal to parietal brain networks is one potential neurophysiologic correlate, but has only been demonstrated in animals or under limited conditions in healthy volunteers.

Methods And Findings: We recruited eighteen patients presenting for surgery under general anesthesia; electroencephalography of the frontal and parietal regions was acquired during (i) baseline consciousness, (ii) anesthetic induction with propofol or sevoflurane, (iii) general anesthesia, (iv) recovery of consciousness, and (v) post-recovery states.

View Article and Find Full Text PDF

Background: Propofol and remifentanil are used for tracheal intubation in the absence of neuromuscular blocking agents. We hypothesized that the addition of sevoflurane to propofol and remifentanil would improve intubation conditions and provide hemodynamic stability.

Methods: Seventy-six patients scheduled for elective surgery were randomly allocated to be ventilated with either 4% (group I) or 7% sevoflurane (group II) after propofol injection (2 mg/kg).

View Article and Find Full Text PDF

Background: Propofol and barbiturates are both known to protect cells of several organs against ischemia/reperfusion injury, but there are few reports on any possible protective effects on human hepatocytes. We investigated the activities of both agents on human hepatic SNU761 cells under hydrogen peroxide (H(2)O(2))-induced oxidative stress.

Methods: To determine whether propofol and pentobarbital protect hepatocytes from H(2)O(2)-induced toxicity, we used SNU761 cells, a human hepatocellular carcinoma (HCC) cell line.

View Article and Find Full Text PDF

Background: The present investigation was undertaken to evaluate the protective effect of propofol and etomidate against hydrogen peroxide (H2O2) induced oxidative damage in human hepatic SNU761 cells by measuring lactate dehydrogenase (LDH).

Methods: The cell line of human hepatocellular carcinoma was grown for 24 hours in dissociated cell culture. They were divided into eight groups: negative control (NC) group with no drug administration, positive control (PC) group with H2O2 250 micrometer and other groups pretreated with propofol (P; 1, 10, 50 micrometer) or etomidate (ET; 1, 10, 50 micrometer) followed H2O2 administration.

View Article and Find Full Text PDF

Hypothesis/objectives: To examine the protective effect of general anesthesia with isoflurane against noise-induced hearing loss in mice.

Study Design: Animal study using noise stimulation and measurement of hearing in BALB/c mice.

Methods: Mice were exposed to 122 dB peak equivalent sound pressure level click noise for 3 hours per day for 3 consecutive days with or without anesthesia using isoflurane.

View Article and Find Full Text PDF