Potential Risk of Choline Alfoscerate on Isoflurane-Induced Toxicity in Primary Human Astrocytes

Objective@#: Isoflurane, a widely used common inhalational anesthetic agent, can induce brain toxicity. The challenge lies in protecting neurologically compromised patients from neurotoxic anesthetics. Choline alfoscerate (L-α-Glycerophosphorylcholine, α-GPC) is recognized for its neuroprotective properties against oxidative stress and inflammation, but its optimal therapeutic window and indications are still under investigation. This study explores the impact of α-GPC on human astrocytes, the most abundant cells in the brain that protect against oxidative stress, under isoflurane exposure. @*Methods@#: This study was designed to examine changes in factors related to isoflurane-induced toxicity following α-GPC administration. Primary human astrocytes were pretreated with varying doses of α-GPC (ranging from 0.1 to 10.0 μM) for 24 hours prior to 2.5% isoflurane exposure. In vitro analysis of cell morphology, water-soluble tetrazolium salt-1 assay, quantitative real-time polymerase chain reaction, proteome profiler array, and transcriptome sequencing were conducted. @*Results@#: A significant morphological damage to human astrocytes was observed in the group that had been pretreated with 10.0 mM of α-GPC and exposed to 2.5% isoflurane. A decrease in cell viability was identified in the group pretreated with 10.0 μM of α-GPC and exposed to 2.5% isoflurane compared to the group exposed only to 2.5% isoflurane. Quantitative real-time polymerase chain reaction revealed that mRNA expression of heme-oxygenase 1 and hypoxia-inducible factor-1α, which were reduced by isoflurane, was further suppressed by 10.0 μM α-GPC pretreatment. The proteome profiler array demonstrated that α-GPC pretreatment influenced a variety of factors associated with apoptosis induced by oxidative stress. Additionally, transcriptome sequencing identified pathways significantly related to changes in isoflurane-induced toxicity caused by α-GPC pretreatment. @*Conclusion@#: The findings suggest that α-GPC pretreatment could potentially enhance the vulnerability of primary human astrocytes to isoflurane-induced toxicity by diminishing the expression of antioxidant factors, potentially leading to amplified cell damage.

Depth of double-lumen endobronchial tube: a comparison between real practice and clinical recommendations using height-based formulae

The depth of double-lumen endobronchial tube (DLT) is reportedly known tobe directly proportional to height and several height-based recommendations have beensuggested. This retrospective study was designed to find out the difference between calculated depths using height-based formulae and realistic depths in clinical practice of DLTplacement by analyzing pooled data from patients intubated with left-sided DLT.Methods: The electronic medical records of adults, intubated with DLT from February 2018to December 2020, were reviewed. Data retrieved included age, sex, height, weight, andsize and depth of DLT. The finally documented DLT depth (depth final, DF) was comparedwith the calculated depths, and the relationship between height and DF was also evaluated.A questionnaire on endobronchial intubation method was sent to anesthesiologists.Results: A total of 503 out of 575 electronic records of consecutive patients were analyzed.Although the relationship between height and DF was shown to have significant correlation(Spearman’s rho = 0.63, P < 0.001), DF was shown to be significantly greater than calculated depths (P < 0.001). Despite 57.1% of anesthesiologists have knowledge of clinical recommendations to anticipate size and depth of DLT, no one routinely utilizes those recommendations.Conclusions: Anesthesiologists tend to place DLTs in a deeper position than expected whendepths are calculated using height-based recommendations. Although such discrepanciesmay not be clinically meaningful, efforts are needed to standardize the methods of endobronchial intubation to prevent potential complications associated with malposition.

Intravenous Versus Perineural Dexamethasone for Reducing Rebound Pain After Interscalene Brachial Plexus Block: A Randomized Controlled Trial

Background@#Interscalene brachial plexus block (ISB) is a common regional technique to manage acute postoperative pain for arthroscopic rotator cuff tear repair. However, rebound pain may compromise its overall benefit. Our aim was to investigate the primary hypothesis that perineural and intravenous dexamethasone have different effects on rebound pain after resolution of ISB for arthroscopic rotator cuff tear repair. @*Methods@#Patients aged ≥ 20 years scheduled for elective arthroscopic rotator cuff tear repair under general anesthesia with preoperative ISB were included. The participants were randomized to receive dexamethasone either perineurally (perineural group) or intravenously (intravenous group). In the perineural group, patients received ISB with 12 mL of 0.5% ropivacaine containing 5 mg of dexamethasone; simultaneously, 1 mL of 0.9% normal saline was administered intravenously. In the intravenous group, patients received ISB with 12 mL of 0.5% ropivacaine; simultaneously, 1 mL of dexamethasone 5 mg was administered intravenously. The primary outcome was the difference in the pain score (0–10 on numeric rating scale) between before and after ISB resolution. The secondary outcomes were the incidence of rebound pain; onset, duration, and intensity of rebound pain; time to the first analgesic request; and pain-related sleep disturbance. @*Results@#A total of 71 patients were randomized to either perineural group (n = 36) or intravenous group (n = 35). After block resolution, pain scores increased significantly more in the perineural group (mean ± standard deviation, 4.9 ± 2.1) compared to the intravenous group (4.0 ± 1.7, P = 0.043). The duration of ISB was more prolonged in the perineural group (median [interquartile range], 19.9 [17.2–23.1] hours) than the intravenous group (15.1 [13.7–15.9] hours, P < 0.001). The incidence of rebound pain and pain-related sleep disturbance during the first postoperative week was significantly higher in the perineural group than in the intravenous group (rebound pain: 44.4% vs. 20.0%, P = 0.028; sleep disturbance: 55.6% vs. 25.7%, P = 0.011). The duration and intensity of rebound pain were similar between the two groups. @*Conclusion@#Although perineural dexamethasone provided longer postoperative analgesia, intravenous dexamethasone was more beneficial in reducing pain increase after ISB resolution, incidence of rebound pain, and pain-related sleep disturbance.

Association between anesthetic method and postpartum hemorrhage in Korea based on National Health Insurance Service data

Postpartum hemorrhage (PPH) is a major cause of maternal mortality and the risk factors for PPH differ among studies. In this large-scale study, we investigated whether the anesthetic method used was associated with PPH after cesarean section. Methods: We extracted data on cesarean sections performed between January 2008 and June 2013 from the National Health Insurance Service database. The anesthetic methods were categorized into general, spinal and epidural anesthesia. To compare the likelihood of PPH among deliveries using different anesthetic methods, crude and adjusted odds ratios (ORs) and 95% confidence intervals were calculated using logistic regression analysis. Results: Data from 330,324 cesarean sections were analyzed, and 21,636 cases of PPH were identified. Univariate analysis showed that general and epidural anesthesia increased the risk of PPH compared to spinal anesthesia. The OR for PPH was highest for morbidly adherent placenta, followed by placenta previa, placental abruption, and hypertension. When other clinical covariates were controlled for, general and epidural anesthesia still remained significant risk factors for PPH compared to spinal anesthesia. Conclusions: This study showed that general and epidural anesthesia elevated the risk of PPH compared to spinal anesthesia during cesarean section. Since we could not consider the potential bias of group differences in indications, more in-depth clinical trials are needed to validate our findings. Obstetric factors such as placental abnormalities had high odds ratios and thus are more important than the choice of anesthetic method, which should be based on the patient’s clinical condition and institutional resources.

Oleanolic Acid Protects the Skin from Particulate Matter-Induced Aging

The role of particulate matter (PM) in health problems including cardiovascular diseases (CVD) and pneumonia is becoming increasingly clear. Polycyclic aromatic hydrocarbons, major components of PM, bind to aryl hydrocarbon receptor (AhRs) and promote the expression of CYP1A1 through the AhR pathway in keratinocytes. Activation of AhRs in skin cells is associated with cell differentiation in keratinocytes and inflammation, resulting in dermatological lesions. Oleanolic acid, a natural component of L. lucidum, also has anti-inflammation, anticancer, and antioxidant characteristics. Previously, we found that PM 10, induced the AhR signaling pathway and autophagy process in keratinocytes. Here, we investigated the effects of oleanolic acid on PM 10,-induced skin aging. We observed that oleanolic acid inhibits PM 10,-induced CYP1A1 and decreases the increase of tumor necrosis factor– alpha and interleukin 6 induced by PM 10,. A supernatant derived from keratinocytes cotreated with oleanolic acid and PM 10, inhibited the release of matrix metalloproteinase 1 in dermal fibroblasts. Also, the AhR-mediated autophagy disruption was recovered by oleanolic acid. Thus, oleanolic acid may be a potential treatment for addressing PM 10,-induced skin aging.

Adverse events of conscious sedation using midazolam for gastrointestinal endoscopy

BACKGROUND: This study was conducted to identify the types and incidence of adverse events associated with midazolam, which is the most widely used drug to induce conscious sedation during gastrointestinal endoscopy, and to analyze the factors associated with hypoxemia and sedation failure.METHODS: Of 87,740 patients who underwent gastrointestinal endoscopy between February 2015 and May 2017, the electronic medical records of 335 who reportedly developed adverse events were retrospectively reviewed, and analysis was performed to determine the risk factors for hypoxemia and sedation failure, the two most frequent adverse events among those manifested during gastrointestinal endoscopy.RESULTS: The overall adverse event rate was 0.38% (n = 335); hypoxemia was most frequent, accounting for 40.7% (n = 90), followed by sedation failure (34.8%, n = 77), delayed discharge from the recovery room (22.1%, n = 49), and hypotension (2.2%, n = 5). Compared with the control group, the hypoxemia group did not show any significant differences in sex and body weight, but mean age was significantly older (P < 0.001) and a significantly lower dose of midazolam was administered (P < 0.001). In the group with sedation failure, the mean rate was higher in men (P < 0.001) and a significantly higher dose of midazolam was administered (P < 0.001), but no age difference was found.CONCLUSIONS: Midazolam-based conscious sedation during gastrointestinal endoscopy can lead to various adverse events. In particular, as elderly patients are at higher risk of developing hypoxemia, midazolam dose adjustment and careful monitoring are required in this group.

A retrospective analysis of neurological complications after ultrasound guided interscalene block for arthroscopic shoulder surgery

BACKGROUND: Ultrasound-guided interscalene brachial plexus block (US-ISB) has been reported to be effective postoperative analgesia for arthroscopic shoulder surgery. Although considered rare, various neurological complications have been reported. We retrospectively evaluated 668 patients for post operation neurological symptoms including hemidiaphragmatic paresis and post-operative neurologic symptoms after US-ISB. METHODS: We performed a retrospective chart review of 668 patients undergoing shoulder surgery with single-shot US-ISB from January 2010 to May 2015. The general anesthesia prior to the US-guided ISB procedure was standardized by expert anesthesiologists. Neurological postoperative complications were evaluated at 48 hours, about 2 weeks, 1 month, 3 months, 6 months, and up to resolution after operation. RESULTS: Three patients (0.4%) developed hemidiaphragmatic paresis (HDP), which were likely US-ISB associated and improved within 1 day. Two patients developed sensory symptoms, also likely US-ISB associated; one was paresthesia at the tip of the thumb/index finger, which resolved within 2 weeks, and the other was hypoesthesia involving the posterior auricular nerve, which resolved within 6 months. Motor and sensory symptoms which were not likely associated with US-ISB were hypoesthesia and pain (n = 28, 4.6%) and motor weakness (n = 2, 0.3%). CONCLUSIONS: Incidence of HDP and neurological complications, respectively 0.4% and 0.3%, related to transient minor sensory symptoms occurred after US-ISB for arthroscopic shoulder surgery but the complications improved spontaneously. Therefore, we confirm that the US-ISB procedure with low volumes of local anesthetics is an acceptable technique with a low rate of HDP and neurological complications.

Hypersensitivity Reaction to Perioperative Drug Mistaken for Local Anesthetic Systemic Toxicity in a Patient under Brachial Plexus Block / 고신대학교의과대학학술지

Perioperative anaphylaxis, although rare, is a severe, life-threatening unexpected systemic hypersensitivity reaction. Simultaneous administration of various drugs during anesthesia, the difficulty of communicate with patients in sedation and anesthesia, and coverage of the patient with surgical drapes are considered to be factors that impede early recognition of anaphylactic reactions. It is very important to perform an intradermal skin test because antibiotics are the most common cause of perioperative anaphylaxis. We report a case of negative-intradermal skin test antibiotic anaphylaxis mistaken for local aesthetic systemic toxicity without increase of serum tryptase for confirmative diagnostic biomaker during surgery under brachial plexus block. It is not possible to exclude the danger of anaphylaxis completely, even if it is negative-intradermal skin test and normal tryptase level. Therefore, anesthesiologists should be closely monitored and treated early for antibiotics related hypersensitive reaction, like other medicines during anesthesia.

Compression stockings reduce the incidence of hypotension but not that of cerebral desaturation events in the beach-chair position: a randomized controlled trial / 대한마취과학회지

BACKGROUND: The beach-chair position (BCP) results in decreases in venous return, cardiac output, and cerebral perfusion pressure. In this randomized, prospective study, we investigated whether applying thigh-high compression stockings affected the maintenance of regional cerebral tissue oxygen saturation (rSO2) in the BCP. METHODS: Patients undergoing orthopedic surgery in the BCP under general anesthesia were included and assigned randomly to the control or the compression stocking group. Appropriately sized thigh-high compression stockings were applied to the patients in the stockings group. All patients were tilted, up to 45°, throughout the operation. Non-invasive blood pressure, invasive arterial blood pressure zeroed at the external auditory meatus, and rSO2 were recorded. RESULTS: Data were analyzed from 19 patients per group. In the BCP, the values of rSO2 and blood pressure decreased significantly compared with those at baseline, with no significant difference between the groups. The incidences of cerebral desaturation events (CDEs) were similar between the groups; however, that of hypotension was significantly lower in the compression stocking group. During 36 CDEs, the levels of rSO2 and blood pressure decreased significantly compared with those at baseline in both groups. No significant correlation was found between rSO2 and blood pressure. CONCLUSIONS: Thigh-high compression stockings reduced the incidence of hypotension but not that of CDEs. Our results suggest that other factors, beyond hypotension itself, contribute to CDEs and in other words, efforts just to reduce the incidence of hypotension may not mainly contribute to a reduction of CDEs occurrence in the BCP under general anesthesia.

Influence of the Phase of Menstrual Cycle on Postoperative Nausea and Vomiting after Breast Cancer Surgery / 이화의대지

OBJECTIVES: The phase of the menstrual cycle was demonstrated to have an influence on the incidence of postoperative nausea and vomiting (PONV) after gynecologic laparoscopic surgery, but little was known for breast surgery, which was shown to have relatively higher incidence of PONV, >60%. We performed this study to investigate the influence of the phase of menstrual cycle on PONV after breast cancer surgery. METHODS: A total of 103 patients, who were scheduled for breast cancer surgery under general anesthesia, were recruited, and patients with irregular menstrual cycles, history of previous history of PONV were excluded. Groups were divided in two ways as follows: 1) gynecologic classification: premenstrual and menstrual (days 25 to 6), follicular (days 8 to 12), ovulation (days 13 to 15), and luteal phase (days 20 to 24); 2) menstrual classification: menstrual (days 1 to 8) and non-menstrual (days 9 to 28). PONV were recorded using Rhodes index of nausea, vomiting and retching at postoperative 6 and 24 hours. RESULTS: The overall incidence of PONV during postoperative 24 hours was 35.4%. At the menstrual classification, the incidence of PONV at postoperative 24 hours was higher in the menstrual group than that in the non-menstrual group (16.7% vs. 4.2%, P=0.057). The severity of PONV, measured with Rhodes index of nausea, vomiting and retching was significantly different between menstrual and non-menstrual groups (P=0.034). CONCLUSION: The duration and severity of the PONV after breast cancer surgery were demonstrated to be prolonged and aggravated during menstruation, respectively. Therefore, consideration of menstrual cycle for scheduling breast cancer surgery could effectively prevent the PONV and reduce medical cost.

Changes in Serum Concentrations of Insulin-like Growth Factor Binding Protein-3 after General Anesthesia Using Propofol or Isoflurane / 이화의대지

OBJECTIVES: The insulin-like growth factor binding proteins (IGFBP) regulate the bioavailability and bioactivity of insulin-like growth factor. We aimed to evaluate whether the IGFBP-3 level undergo major changes during perioperative periods according to the different kind of anesthetic agents. METHODS: Eighteen adults scheduled for elective total abdominal hysterectomy were enrolled. The patients were randomly assigned to have either propofol or isoflurane for maintenance of general anesthesia. A venous sample was taken for analysis of IGFBP-3 at the following time points: before induction, at the time of peritoneal closure, 1 hour after extubation at recovery room, and 2 and 5 postoperative days. The samples were analyzed by enzyme linked immunosolvent assay. RESULTS: Demographic data were similar between groups. In the both groups, the IGFBP-3 concentration decreased after anesthesia induction, reaching a nadir at the time of peritoneal closure without a significant difference between groups. In analysis between groups, the IGFBP-3 concentration in the isoflurane group on the postoperative 5th day was recovered to preoperative value and significantly higher than that in the propofol group (P < 0.05). CONCLUSION: This is the first study to show that the anesthetics used for general anesthesia affect the IGFBP-3 level during perioperative periods. The decrease of IGFBP-3 level following anesthesia induction in the isoflurane group was recovered to preoperative value, whereas that observed in the propofol group was not recovered on the postoperative 5th day. Further study is needed to establish the definitive effect of general anesthetics on IGFBP-3 and provide a comprehensive interpretation.

Lead fracture of peripheral nerve stimulator for brachial plexopathy: a case report / 대한마취과학회지

Peripheral nerve stimulation (PNS) is a useful treatment for chronic pain, but it can cause damage depending on its application site. Here, we describe the case of a 54-year-old man who underwent PNS for brachial plexopathy in 2015. One lead was implanted on the left medial cord to stimulate the medial antebrachial cutaneous nerve, and the other was implanted on the radial nerve to stimulate the posterior antebrachial cutaneous nerve. Both leads were inserted near the shoulder joint but did not cross it. Before PNS, the patient did not move his shoulder and elbow because of severe pain, but the treatment greatly alleviated this pain. Twenty months after the operation, both leads were fractured, and the severe pain returned. Repetitive motion near the joint was closely related to the lead fractures. In conclusion, large joints as the insertion sites of PNS leads should be avoided to prevent lead fractures.

Retrospective Analysis of Difficult Intubation / 이화의대지

OBJECTIVES: We analyzed retrospectively incidence, management, and predictors of difficult intubation, which have been known through practical cases. METHODS: A total of 217 cases of difficult intubation (DI) between 2010 and 2014 were investigated. Risk factors such as age, body mass index, Mallampati score, thyromental distance, degree of mouth opening and range of neck motion, Cormack-Lehane grade, intubation and airway management techniques were investigated. The cases of each department were analyzed and the airway management techniques according to simplified risk scores (SRS) were also investigated. RESULTS: The average incidence of DI was 0.49%. Patients undergoing surgery in the departments of oro-maxillo-facial surgery (1.35%), ophthalmologic surgery (0.96%), urologic surgery (0.80%), and head and neck surgery of ear-nose-throat (0.62%) showed the higher incidence of DI. Difficult mask ventilation (10 of 217, 4.6%) was occurred with DI. Higher SRS were related to high rates of video laryngoscope use and fiberoptic guided intubation. There was a decrease in the use of McCoy blades after 2013, an increase in the use of video laryngoscope, and a consistent rate of fiberoptic intubation. CONCLUSION: It is not easy to check all the predictors of DI in a preanesthetic evaluation and the predictors are not accurate. The role of clinical preparation and practical management is important, and the most important thing is to establish a planned induction strategy. Multiple factors system, such as simplified risk factors should be used to evaluate patients to prepare for appropriate airway management techniques in case of DI.

Hypoesthesia of the Cutaneous Branch of Cervical Plexus after Shoulder Arthroscopy under General Anesthesia with Ultrasound Guided-Interscalene Block / 이화의대지

We present an uncommon case of hypoesthesia in the posterior and upper third of the superior area on the left ear auricle, after arthroscopic surgery of the shoulder in the lateral position under general anesthesia with ultrasound guided-interscalene brachial plexus block. A 65-year-old man underwent arthroscopic rotator cuff repair of the left shoulder in the right lateral decubitus position. Two days after operation, he complained of numbness around the left auricle; his symptoms persisted until 6 weeks after surgery. Audiometry and sensory examinations were normal. He recovered naturally by 6 months postoperatively. Postoperative neurological deficits that may not be block-related can be attributed to a combination of factors, such as patient-, anesthesia-, and surgery-related factors, including direct trauma, positioning, and retraction. Anesthesiologists should be aware that the injury may not be block-related and consider other possible causes.

Dyspnea due to Residual Neuromuscular Blockade in Elderly Patient with Unrecognized Pre-existing Unilateral Vocal Cord Paralysis / 이화의대지

Muscle relaxation using neuromuscular blocking agent is an essential process for endotracheal intubation and surgery, and requires adequate recovery of muscle function after surgery. Residual neuromuscular blockade is defined as an insufficient neuromuscular recovery that can be prevented by confirming train-of-four ratio >0.9 using objective neuromuscular monitoring. Sugammadex, a novel selective relaxant-binding agent, produces rapid and effective reversal of rocuronium-induced neuromuscular blockade. We report a case of the residual neuromuscular blockade accompanying dyspnea and stridor after general anesthesia in an unrecognized pre-existing symptomless unilateral vocal cord paralysis patient, who had experienced the disappearance of dyspnea and stridor after administration of sugammadex.

Effect of short-term prewarming on body temperature in arthroscopic shoulder surgery

BACKGROUND: Hypothermia (< 36°C) is common during arthroscopic shoulder surgery. It is known that 30 to 60 minutes of prewarming can prevent perioperative hypothermia by decreasing body heat redistribution. However, the effect of short-term prewarming (less than 30 minutes) on body temperature in such surgery has not been reported yet. Therefore, the aim of this prospective study was to investigate the effect of short-term prewarming for less than 30 minutes using forced-air warming device on body temperature during interscalene brachial plexus block (ISBPB) procedure in arthroscopic shoulder surgery before general anesthesia. METHODS: We randomly assigned patients scheduled for arthroscopic shoulder surgery to receive either cotton blanket (not pre-warmed, group C, n = 26) or forced-air warming device (pre-warmed, group F, n = 26). Temperature was recorded every 15 minutes from entering the operating room until leaving post-anesthetic care unit (PACU). Shivering and thermal comfort scale were evaluated during their stay in the PACU. RESULTS: There were significant differences in body temperature between group C and group F from 30 minutes after induction of general anesthesia to 30 minutes after arrival in the PACU (P < 0.05). The median duration of prewarming in group F was 14 min (range: 9-23 min). There was no significant difference in thermal comfort scale or shivering between the two groups in PACU. CONCLUSIONS: Our results showed that short-term prewarming using a forced-air warming device during ISBPB in arthroscopic shoulder surgery had beneficial effect on perioperative hypothermia.

Effect of short-term prewarming on body temperature in arthroscopic shoulder surgery

BACKGROUND: Hypothermia (< 36°C) is common during arthroscopic shoulder surgery. It is known that 30 to 60 minutes of prewarming can prevent perioperative hypothermia by decreasing body heat redistribution. However, the effect of short-term prewarming (less than 30 minutes) on body temperature in such surgery has not been reported yet. Therefore, the aim of this prospective study was to investigate the effect of short-term prewarming for less than 30 minutes using forced-air warming device on body temperature during interscalene brachial plexus block (ISBPB) procedure in arthroscopic shoulder surgery before general anesthesia. METHODS: We randomly assigned patients scheduled for arthroscopic shoulder surgery to receive either cotton blanket (not pre-warmed, group C, n = 26) or forced-air warming device (pre-warmed, group F, n = 26). Temperature was recorded every 15 minutes from entering the operating room until leaving post-anesthetic care unit (PACU). Shivering and thermal comfort scale were evaluated during their stay in the PACU. RESULTS: There were significant differences in body temperature between group C and group F from 30 minutes after induction of general anesthesia to 30 minutes after arrival in the PACU (P < 0.05). The median duration of prewarming in group F was 14 min (range: 9-23 min). There was no significant difference in thermal comfort scale or shivering between the two groups in PACU. CONCLUSIONS: Our results showed that short-term prewarming using a forced-air warming device during ISBPB in arthroscopic shoulder surgery had beneficial effect on perioperative hypothermia.

The Efficacy of Additional Intravenous Patient-controlled Analgesia to the Interscalene Block in Arthroscopic Shoulder Surgery: A Prospective Randomized Controlled Study

BACKGROUND: The purpose is to determine the efficacy of additional intravenous patient-controlled analgesia (IV-PCA) by comparing the analgesic effects between interscalene block (ISB) combined with IV-PCA and single ISB after arthroscopic shoulder surgery. METHODS: A total of 213 patients who underwent arthroscopic shoulder surgery were divided into two groups based on the type of perioperative anesthesia. The single ISB group included 100 patients, while the IV-PCA group included 113 patients. The visual analogue scale for pain (VAS pain) scores were assessed at 12, 24, and 48 hours postoperatively in accordance with shoulder pathology. Postoperative narcotics-related complications and consumption of additional non-steroidal anti-inflammatory drugs between the two groups were compared. RESULTS: VAS pain showed no significant difference between the two groups at most points of the postoperative timeline, regardless of shoulder pathology, except in patients with rotator cuff repair at postoperative 24 hours. Although the IV-PCA group showed a statistically lower VAS pain score than the ISB group at postoperative 24 hours (p=0.04), the difference in the VAS pain score was only 9.0 mm in patients with rotator cuff repair. Narcotics-related complications were observed more frequently in the IV-PCA group than in the ISB group for patients with rotator cuff repair. CONCLUSIONS: Additional IV-PCA demonstrated no booster effect for immediate pain control in patients undergoing arthroscopic shoulder surgery with preoperative single ISB. Furthermore, patients with IV-PCA experienced greater narcotics-related complications.

The Efficacy of Additional Intravenous Patient-controlled Analgesia to the Interscalene Block in Arthroscopic Shoulder Surgery: A Prospective Randomized Controlled Study

BACKGROUND: The purpose is to determine the efficacy of additional intravenous patient-controlled analgesia (IV-PCA) by comparing the analgesic effects between interscalene block (ISB) combined with IV-PCA and single ISB after arthroscopic shoulder surgery. METHODS: A total of 213 patients who underwent arthroscopic shoulder surgery were divided into two groups based on the type of perioperative anesthesia. The single ISB group included 100 patients, while the IV-PCA group included 113 patients. The visual analogue scale for pain (VAS pain) scores were assessed at 12, 24, and 48 hours postoperatively in accordance with shoulder pathology. Postoperative narcotics-related complications and consumption of additional non-steroidal anti-inflammatory drugs between the two groups were compared. RESULTS: VAS pain showed no significant difference between the two groups at most points of the postoperative timeline, regardless of shoulder pathology, except in patients with rotator cuff repair at postoperative 24 hours. Although the IV-PCA group showed a statistically lower VAS pain score than the ISB group at postoperative 24 hours (p=0.04), the difference in the VAS pain score was only 9.0 mm in patients with rotator cuff repair. Narcotics-related complications were observed more frequently in the IV-PCA group than in the ISB group for patients with rotator cuff repair. CONCLUSIONS: Additional IV-PCA demonstrated no booster effect for immediate pain control in patients undergoing arthroscopic shoulder surgery with preoperative single ISB. Furthermore, patients with IV-PCA experienced greater narcotics-related complications.

The Skin-to-epidural distance of parturients by ultrasonography: sitting position versus left lateral position

BACKGROUND: Pre-procedural lumbar ultrasound scanning is a reliable tool to estimate the skin to epidural distance (SED). We conducted an observational study to compare the SED between the sitting position and lateral position using pre-procedural ultrasound imaging of the lumbar spine in parturients. METHODS: Using a 2–5 MHz curvilinear transducer, we obtained images of the lumbar interspaces from L2-3 to L5-S1 in the paramedian sagittal oblique view. The individual distance from the skin to the ligamentum flavum-dura mater unit was measured at the level of L2-3, L3-4, L4-5, and L5-S1 in the left lateral position (distance in lateral position; D-lat). Subsequently, participants were placed in the sitting position, and the distance was measured in the same manner (distance in sitting position; D-sit). Data were grouped according to body mass index (BMI; kg/m²) measurements of ≥ 25 or < 25 and analyzed. The primary outcome was the change determined by ultrasound between D-lat and D-sit at the same lumbar level according to position. RESULTS: Thirty parturients were studied. The difference between D-lat and D-sit in the same lumbar level was not statistically significant. The mean changes between D-lat and D-sit in the same lumbar level were less than 0.18 cm. In BMI ≥ 25 group, the difference between D-lat and D-sit were greater than that of BMI < 25 group at L3-4 level (P = 0.042). CONCLUSIONS: It is important for clinicians to consider that position change is associated with greater differences in SED in obese parturients (BMI ≥ 25) compared with thin parturients (BMI < 25). For obese parturients, the sitting position may be helpful.