Use of vasopressors to manage spinal anesthesia-induced hypotension during cesarean delivery.

Cesarean sections are commonly performed under spinal anesthesia, which can lead to hypotension, adversely affecting maternal and fetal outcomes. Hypotension following spinal anesthesia is generally defined as a blood pressure of 80-90% below the baseline value. Various strategies have been implemented to reduce the incidence of spinal anesthesia-induced hypotension. The administration of vasopressors is a crucial method for preventing and treating hypotension. In the past decade, phenylephrine, a primarily alpha-adrenergic agonist, has been the preferred vasopressor for cesarean sections. Recently, norepinephrine, a potent alpha-agonist with modest beta-agonist activity, has gained popularity owing to its advantages over phenylephrine. Vasopressors can be administered via a bolus or continuous infusion. Although administering boluses alone is simpler in a clinical setting, continuous prophylactic infusion initiated immediately after spinal anesthesia is more effective in reducing the incidence of hypotension. Tailoring the infusion dose based on the patient's body weight and adjusting the rate in response to blood pressure changes, in addition to using a prophylactic or rescue bolus, helps reduce blood pressure variability during cesarean sections under spinal anesthesia until neonatal delivery.

Utilizing ChatGPT in clinical research related to anesthesiology: a comprehensive review of opportunities and limitations.

Chat generative pre-trained transformer (ChatGPT) is a chatbot developed by OpenAI that answers questions in a human-like manner. ChatGPT is a GPT language model that understands and responds to natural language created using a transformer, which is a new artificial neural network algorithm first introduced by Google in 2017. ChatGPT can be used to identify research topics and proofread English writing and R scripts to improve work efficiency and optimize time. Attempts to actively utilize generative artificial intelligence (AI) are expected to continue in clinical settings. However, ChatGPT still has many limitations for widespread use in clinical research, owing to AI hallucination symptoms and its training data constraints. Researchers recommend avoiding scientific writing using ChatGPT in many traditional journals because of the current lack of originality guidelines and plagiarism of content generated by ChatGPT. Further regulations and discussions on these topics are expected in the future.

Effect of intraoperative blood transfusion on inflammatory response in parturients with placenta previa undergoing cesarean section: A prospective observational study.

Background: The neutrophil to lymphocyte ratio (NLR), platelet to lymphocyte ratio (PLR), and red cell distribution width (RDW) have been reported as useful biomarkers for evaluating inflammation and a predictor of surgical prognosis. Although there have been recent reports that transfusion may affect inflammatory responses, studies on the post-transfusion inflammatory response in parturients are rare. Therefore, this study aimed to observe changes in inflammatory response after transfusion during cesarean section (C-sec) through NLR, PLR, and RDW. Methods: Parturients aged 20-50 years who underwent C-sec under general anesthesia due to placenta previa totalis from March 4, 2021, to June 10, 2021 were participated in this prospective observational study. We compared postoperative NLR, PLR, and RDW between the transfusion and non-transfusion groups. Results: A total of 53 parturients were included in this study, of which 31 parturients received intraoperative transfusions during C-sec. There were no significant difference in preoperative NLR (3.6 vs. 3.4, p = 0.780), PLR (132.8 vs. 111.3, p = 0.108), and RDW (14.2 vs. 13.6, p = 0.062) between the two groups. However, postoperative NLR was significantly higher in the transfusion group than in the non-transfusion group (12.2 vs. 6.8, p < 0.001). Postoperative RDW was significantly higher in the transfusion group than in the non-transfusion group (14.6 vs. 13.9, p = 0.002) whereas postoperative PLR was not significantly different between the two groups (108.0 vs. 117.4, p = 0.885). Conclusions: Postoperative NLR and RDW, the inflammatory biomarkers, were significantly higher in the transfused C-sec parturients. These results suggest a significant association between postoperative inflammatory response and transfusion in obstetric practice.

Association of red cell distribution width/albumin ratio with intraoperative blood transfusion in cervical cancer patients.

BACKGROUND: Although minimally invasive surgical techniques have reduced intraoperative bleeding, the risk of transfusion exists. However, few studies have evaluated risk factors for transfusion in radical hysterectomy. We aimed to evaluate the association between preoperative red cell distribution width/albumin ratio (RDW/albumin) and transfusion in cervical cancer patients. METHODS: We analyzed 907 patients who underwent radical hysterectomy between June 2006 and February 2015. Logistic regression and Cox regression analyses were performed to determine the risk factors for transfusion and mortality at 5-year and overall. Net reclassification improvement (NRI) and integrated identification improvement (IDI) analyses were performed to verify the improvement of the intraoperative transfusion model upon the addition of RDW/albumin. RESULTS: RDW/albumin was an independent risk factor for transfusion (odds ratio [OR]: 1.34, 95% confidence interval [CI]: 1.02-1.77, p = 0.035). Additionally, body mass index, operation time, laparoscopic surgery, total fluids, and synthetic colloid were risk factors for transfusion. RDW/albumin was an independent risk factor for 5-year mortality (hazard ratio [HR]: 1.51, 95% CI: 1.07-2.14, p = 0.020), and overall mortality (HR: 1.48, 95% CI: 1.06-2.07, p = 0.021). NRI and IDI analyses showed the discriminatory power of RDW/albumin for transfusion (p<0.001 and p = 0.046, respectively). CONCLUSIONS: RDW/albumin might be a significant factor in transfusion and mortality in cervical cancer patients.

Low Preoperative Lymphocyte-to-Monocyte Ratio Is Predictive of the 5-Year Recurrence of Bladder Tumor after Transurethral Resection.

Many studies have investigated the prognostic significance of peripheral blood parameters-including lymphocyte-to-monocyte ratio (LMR)-in several cancers in recent decades. We evaluated the prognostic factors for five-year tumor recurrence after the transurethral resection of a bladder tumor (TURBT). In total, 151 patients with non-muscle invasive bladder tumors who underwent TURBT under spinal anesthesia were selected for this retrospective analysis. The time to tumor recurrence was determined by the number of days from surgery until there was a pathological confirmation of tumor recurrence. The preoperative and postoperative laboratory values were defined as results within one month prior to and one month after TURBT. Univariate and multivariate Cox regression analyses were performed. Seventy-one patients (47.0%) developed recurrent bladder tumors within five years after the first TURBT surgery. The multivariate Cox regression analysis revealed that preoperative LMR (hazard ratio, 0.839; 95% confidence interval, 0.739-0.952; p = 0.006) and multiple tumor sites (hazard ratio, 2.072; 95% confidence interval, 1.243-3.453; p = 0.005) were independent recurrence predictors in patients with recurrent bladder tumors within five years after the TURBT. A low preoperative LMR is an important predictor for the recurrence of a bladder tumor during a five-year follow-up period after surgery.

Effects of Perioperative Inflammatory Response in Cervical Cancer: Laparoscopic versus Open Surgery.

There are few studies between postoperative neutrophil to lymphocyte ratio (NLR) and survival in cervical cancer. We compared postoperative changes in NLR according to surgical methods and analyzed the effect of these changes on 5-year mortality of cervical cancer patients. A total of 929 patients were assigned to either the laparoscopic radical hysterectomy (LRH) (n = 721) or open radical hysterectomy (ORH) (n = 208) group. Propensity score matching analysis compared the postoperative NLR changes between the two groups, and multivariate logistic regression analysis evaluated the association between NLR changes and 5-year mortality. Surgical outcomes between the two groups were also compared. In the LRH group, NLR changes at postoperative day (POD) 0 and POD 1 were significantly lower than in the ORH group after matching (NLR change at POD 0, 10.4 vs. 14.3, p < 0.001; NLR change at POD 1, 3.5 vs. 5.4, p < 0.001). In multivariate logistic regression analysis, postoperative NLR change was not associated with 5-year mortality (2nd quartile: OR 1.55, 95% CI 0.56-4.29, p = 0.401; 3rd quartile: OR 0.90, 95% CI 0.29-2.82, p = 0.869; 4th quartile: OR 1.40, 95% CI 0.48-3.61, p = 0.598), whereas preoperative NLR was associated with 5-year mortality (OR 1.23, 95% CI 1.06-1.43, p = 0.005). After matching, there were no significant differences in surgical outcomes between the two groups. There were significantly fewer postoperative changes of NLR in the LRH group. However, the extent of these NLR changes was not associated with 5-year mortality. By contrast, preoperative NLR was associated with 5-year mortality.

Importance of Preoperative Screening Strategies for Coronavirus Disease 2019 in Patients Undergoing Cesarean Sections: A Retrospective, Large Single-Center, Observational Cohort Study.

During the coronavirus disease 2019 (COVID-19) pandemic, many guidelines have recommended postponing non-emergency operations. However, cesarean sections cannot be indefinitely delayed. Our institution has established a COVID-19 screening strategy for patients undergoing cesarean section. We evaluated the usefulness of this screening strategy. Parturients undergoing cesarean section at our center during the first peak of the COVID-19 outbreak were retrospectively analyzed. Each parturient underwent a questionnaire survey evaluating epidemiological correlation and symptoms at admission. Reverse transcriptase-polymerase chain reaction (RT-PCR) testing and/or chest radiography were performed. In total, 296 parturients underwent cesarean section. All elective and 37 emergency cesarean sections were performed in general operating rooms because they were considered to have a low risk of COVID-19 infection through the screening process. However, 42 emergency cases were performed in negative-pressure operating rooms with full personal protective equipment (PPE) because the RT-PCR results could not be confirmed in a timely manner. None of them were positive for RT-PCR, and there were no cases of nosocomial infection. A comprehensive preoperative screening strategy, including symptomatic and epidemiological correlation, PCR, and/or imaging test, should be performed in patients undergoing cesarian section. Further, cesarean sections in parturients with unconfirmed COVID-19 status should be performed in a negative-pressure operating room with appropriate PPE.

Perinatal outcome of fetuses with congenital high airway obstruction syndrome: a single-center experience.

OBJECTIVE: To report our experience with management of fetuses with congenital high airway obstruction syndrome (CHAOS). METHODS: We retrospectively reviewed the cases of fetuses who were prenatally diagnosed and postnatally confirmed with CHAOS between 2010 and 2019 at Asan Medical Center, Seoul, Korea. RESULTS: Of 13 fetuses prenatally diagnosed with CHAOS, 7 were lost to follow-up and 6 were postnatally confirmed as having CHAOS. All fetuses, except one were delivered via cesarean section with an ex utero intrapartum treatment (EXIT) procedure. Two patients had coexisting congenital heart diseases requiring several cardiac surgeries following birth. Both of these patients demonstrated developmental delay; however, the remaining 4 had a normal development except for expressive language. Two infants died of respiratory complications, and the remaining 4 were alive at the end of the follow-up period. All 4 live patients underwent tracheostomy with planned reconstruction surgery. Three children are now able to phonate, and 1 can maintain a conservation. CONCLUSION: The proper management of CHAOS using the EXIT procedure results in high survival and low hypoxemia-induced complication rates. Therefore, an accurate prenatal diagnosis is necessary for an appropriate perinatal management.

Changes in diaphragmatic excursion and lung compliance during gynaecologic surgery: open laparotomy versus laparoscopy-a prospective observational study.

This study compared the effects of open versus laparoscopic radical hysterectomy on intraoperative diaphragmatic excursion and lung compliance. We enrolled 20 women per group; Group O's members underwent open radical hysterectomy, while Group L's members underwent laparoscopic radical hysterectomy. Diaphragmatic excursion was measured by assessing tidal ventilation using M-mode ultrasonography before intubation (T0), after intubation with mechanical ventilation (T1), 90 min after incision (T2), and at the end of the operation with recovery of muscle relaxation (T3). Peak inspiratory pressure and static lung compliance were measured using an anaesthesia machine combined with a ventilator. Diaphragmatic excursion was significantly lower in Group L than in Group O at T2 (5.3 ± 1.7 mm vs. 7.7 ± 2.0 mm, P < 0.001) and T3 (8.4 ± 1.9 vs. 10.4 ± 2.4, P = 0.011). Impaired diaphragmatic excursion at T3 (< 10 mm under mechanical ventilation) occurred in 15 patients (83.3%) in Group L and seven (38.9%) in Group O (P = 0.006). Changes over time in peak inspiratory pressure and static lung compliance differed significantly between the two groups (P < 0.001 each). Laparoscopic radical hysterectomy decreased diaphragmatic excursion and static lung compliance significantly more than open radical hysterectomy.Korean clinical trial number: Korean Clinical Trials Registry (KCT0004477) (Date of registration: November 18 2019) ( https://cris.nih.go.kr/cris/search/search_result_st01_en.jsp?seq=14963<ype=&rtype= ).

Comparison of electroencephalogram between propofol- and thiopental-induced anesthesia for awareness risk in pregnant women.

There have been few comparative studies using electroencephalogram (EEG) spectral characteristics during the induction of general anesthesia for cesarean section. This retrospective study investigated the differences in the depth of anesthesia through EEG analysis between propofol- and thiopental-induced anesthesia. We reviewed data of 42 patients undergoing cesarean section who received either thiopental (5 mg/kg) or propofol (2 mg/kg). EEG data were extracted from the bispectral index (BIS) monitor, and 10-second segments were selected from the following sections: 1) Stage I, BIS below 60 after induction; 2) Stage II, after intubation completion; 3) Stage III, end-tidal sevoflurane above 0 vol%. The risk of awareness was represented by the BIS and entropy measures. In Stage III, the thiopental group (n = 20) showed significantly higher BIS value than the propofol group (n = 22) (67.9 [18.66] vs 44.5 [20.63], respectively, p = 0.002). The thiopental group had decreased slow-delta oscillations and increased beta-oscillations as compared to the propofol group in Stages II and III (p < 0.05). BIS, spectral entropy, and Renyi permutation entropy were also higher in the thiopental group at Stages II and III (p < 0.05). In conclusion, frontal spectral EEG analysis demonstrated that propofol induction maintained a deeper anesthesia than thiopental in pregnant women.

Changes of diaphragmatic excursion and lung compliance during major laparoscopic pelvic surgery: A prospective observational study.

Major laparoscopic pelvic surgery requires steep Trendelenburg position with pneumoperitoneum for a long time. We investigated the effect of Trendelenburg position with pneumoperitoneum on diaphragmatic excursion and lung compliance during major laparoscopic pelvic surgery using M-mode sonography. Twenty patients undergoing elective pelviscopic radical hysterectomy were included in this study. Diaphragmatic excursion was measured at the following time points; after sedation, after intubation, 90 minutes after Trendelenburg position with pneumoperitoneum, and after operation with recovery of muscle relaxation. And lung compliance was measured using anesthetic machine under general anesthesia; after the intubation, 90 minutes after Trendelenburg position with pneumoperitoneum and after operation with recovery of muscle relaxation. In order to detect postoperative pulmonary complication, postoperative chest radiography was checked. Static lung compliance, dynamic lung compliance and diaphragmatic excursion were decreased during operation (P < 0.001, respectively). At the end of the operation with recovery of muscle relaxation, reduced diaphragmatic movement was not recovered as its excursion after sedation (P < 0.001). In conclusion, lung compliance was decreased following transiently decreased diaphragmatic excursion during major laparoscopic pelvic surgery.

Ex utero intrapartum treatment procedure in two fetuses with airway obstruction.

The ex utero intrapartum treatment (EXIT) procedure was introduced to reduce fetal hypoxic damage while establishing an airway in fetuses with upper and lower airway obstruction. Delivery of the fetal head and shoulders while maintaining the uteroplacental circulation offers time to secure the fetal airway. Here, we report two cases of EXIT procedure for fetal airway obstruction, which were successfully managed with extensive preoperative planning by a professional multidisciplinary team.

Ultrasound-Guided Genicular Nerve Block for Knee Osteoarthritis: A Double-Blind, Randomized Controlled Trial of Local Anesthetic Alone or in Combination with Corticosteroid.

BACKGROUND: Recently, several studies suggested that radiofrequency (RF) ablation of the genicular nerves is a safe and effective therapeutic procedure for intractable pain associated with chronic knee osteoarthritis (OA). Diagnostic genicular nerve block (GNB) with local anesthetic has been generally conducted before making decisions regarding RF ablation. Although GNB has been recently performed together with corticosteroid, the analgesic effects of corticosteroids for treating chronic pain remain controversial. OBJECTIVES: The current study aims to assess the effects of combining corticosteroids and local anesthesia during ultrasound-guided GNB in patients with chronic knee OA. STUDY DESIGN: A randomized, double-blinded institutional study. SETTING: This study took place at Asan Medical Center in Seoul, Korea. METHODS: Forty-eight patients with chronic knee OA were randomly assigned to either the lidocaine alone group (n = 24) or lidocaine plus triamcinolone (TA) group (n = 24) before ultrasound-guided GNB. Visual analog scale (VAS), Oxford Knee Score (OKS), and global perceived effects (7-point scale) were assessed at baseline and at 1, 2, 4, and 8 weeks after the procedure. RESULTS: The VAS scores were significantly lower in the lidocaine plus TA group than in the lidocaine alone group at both 2 (P < 0.001) and 4 (P < 0.001) weeks after GNB. The alleviation of intense pain in the lidocaine plus TA group was sustained up to 2 weeks after the procedure, in accordance with the definition of a minimal clinically important improvement. Although a similar intergroup difference in OKSs was observed at 4 weeks (P < 0.001), the clinical improvement in functional capacity lasted for only one week after the reassessment of OKSs, in accordance with a minimal important change. No patient reported any postprocedural adverse events during the follow-up period. LIMITATIONS: The emotional state of the patients, which might affect the perception of knee pain, was not evaluated. The follow-up period was 2 months; this period might be insufficient to validate the short-term effects of GNB. CONCLUSIONS: Ultrasound-guided GNB, when combined with a local anesthetic and corticosteroid, can provide short-term pain relief. However, the clinical benefit of corticosteroid administration was not clear in comparison with local anesthesia alone. Given the potential adverse effects, corticosteroids might not be appropriate as adjuvants during a GNB for chronic knee OA.The study protocol was approved by our institutional review board (2012-0210), and written informed consent was obtained from all patients. The trial was registered with the Clinical Research Information Service (KCT 0001139). KEY WORDS: Chronic pain, knee osteoarthritis, genicular nerve block, ultrasound, corticosteroid, local anesthetic, visual analog scale, Oxford Knee Score.

Comparison of the effect of spinal anesthesia and general anesthesia on 5-year tumor recurrence rates after transurethral resection of bladder tumors.

Non-muscle invasive bladder tumors are early-stage tumors with high recurrence rates. Transurethral resection of bladder tumor (TURB) is performed under spinal or general anesthesia; however, the effect of the two anesthetic techniques on non-muscle invasive bladder tumor recurrence is unknown. Thus, we compared their effects on tumor recurrence rates five years after TURB. Data from 876 patients who underwent TURB from 2000 to 2007 was reviewed. Patients received spinal or general anesthesia based on their choice or the clinician's preference. Tumor recurrence five years after TURB was assessed using multivariate Cox regression model, propensity score analysis (matching and inverse probability of treatment weighting), and Kaplan-Meier method. The five-year tumor recurrence rate after TURB was 42% and 53% for spinal and general anesthesia groups, respectively (P = 0.013). Hazard ratios for tumor recurrence in the spinal anesthesia group compared to that in the general anesthesia group were 0.619 (P <0.001), 0.642 (P = 0.001), and 0.636 (P <0.001) in the Cox regression model, Cox regression model with propensity score matching, and adjusted analysis with inverse probability of treatment weighting, respectively. The five-year tumor recurrence rate was significantly lower in the spinal anesthesia group than in the general anesthesia group in both the unadjusted (P = 0.002) and adjusted Kaplan-Meier curves (P <0.001). Therefore, spinal anesthesia for non-muscle invasive bladder tumor resection was associated with a lower five-year tumor recurrence rate than general anesthesia. This finding provides useful information for an appropriate selection of anesthetic technique for TURB.

Development of a scoring system to predict massive postpartum transfusion in placenta previa totalis.

PURPOSE: It is important to predict massive postpartum hemorrhage in patients with placenta previa totalis (PPT) and a method that accurately predicts this event is needed. The present study developed a scoring system that predicts massive transfusion in patients with PPT. METHODS: This single-center retrospective cohort study comprised 238 patients with PPT who underwent caesarean section between January 2004 and December 2010. Massive transfusion was defined as the transfusion of ≥8 units of packed red blood cells within 24 h after delivery. Multivariate regression analysis was used to estimate the risks of massive transfusion. A probability score model was then constructed and tested for performance. Subsequently, the model was validated in other patients with PPT (n = 117). RESULTS: Thirty-one patients (13.0%) underwent massive transfusion. Ultrasound suspicion of placental adhesion, previous caesarean section, gestational age <37 weeks, sponge-like appearance of the cervix, and anterior placenta were all independent predictors of massive transfusion. The performance for the score model revealed good calibration (Hosmer-Lemeshow chi-squared 1.64; P = 0.44), and its discrimination (the area under the receiver operating characteristic for this model was 0.84) was better than when suspicion of placental adhesion was used alone (0.67; P < 0.001). In the validation set, the performance was 0.88. CONCLUSION: The scoring system developed using the five independent risk factors had better performance to predict massive transfusion in patients with PPT than when suspicion of placental adhesion was used alone. However, further large-scale studies are warranted to clarify the usefulness and accuracy of this model.

Vagolytic atropine attenuates cerebral vasodilation response during acute orthostatic hypotension.

BACKGROUND: Atropine is an anticholinergic drug which is commonly used in clinical practice. The effect of parasympathetic block with atropine on dynamic cerebrovascular regulation remains unclear. This study was aimed to identify effects of vagolytic atropine on cerebrovascular response during acute orthostatic hypotension in humans. METHODS: Continuous middle cerebral blood flow velocity (CBFV, transcranial Doppler) and arterial blood pressure (ABP, Finometer) were measured during a sit-to-stand procedure in 10 healthy subjects with placebo and vagolytic (10 µg/kg) doses of atropine. Cerebral vascular tone was assessed by cerebrovascular resistance (CVR = ABP / CBFV). Dynamic cerebral autoregulation was also assessed by transfer function analysis of ABP and CBFV. RESULTS: During the standing session, ABP fell to a similar extent in both groups by an average of 23 to 25 mmHg (26% to 29%). CBFV also fell in all subjects but significantly more in vagolytic atropine (-15.0 ± 7.0 cm/s) compared with placebo (-12.0 ± 5.8 cm/s, P < 0.05). CVR was decreased significantly in the placebo group during posture change (1.56 ± 0.44 vs. 1.38 ± 0.38, P < 0.05), in contrast, lesser decreased in the atropine group (1.60 ± 0.50 vs. 1.53 ± 0.42, P = 0.193). Transfer function coherence in the very-low-frequency range was significantly increased in the atropine group during the standing session (0.55 ± 0.14), compared with the sitting session (0.45 ± 0.14, P = 0.006). CONCLUSIONS: These data present that vagolytic atropine attenuates cerebral vasodilation response to acute orthostatic hypotension, suggesting the use of atropine may need care in patients with cerebrovascular disease with vagal impairment.

Unreliable Tracking Ability of the Third-Generation FloTrac/Vigileo™ System for Changes in Stroke Volume after Fluid Administration in Patients with High Systemic Vascular Resistance during Laparoscopic Surgery.

BACKGROUND: The FloTrac/Vigileo™ system does not thoroughly reflect variable arterial tones, due to a lack of external calibration. The ability of this system to measure stroke volume and track its changes after fluid administration has not been fully evaluated in patients with the high systemic vascular resistance that can develop during laparoscopic surgery. METHODS: In 42 patients undergoing laparoscopic prostatectomy, the stroke volume derived by the third-generation FloTrac/Vigileo™ system (SV-Vigileo), the stroke volume measured using transesophageal echocardiography (SV-TEE) as a reference method, and total systemic vascular resistance were evaluated before and after 500 ml fluid administration during pneumoperitoneum combined with the Trendelenburg position. RESULTS: Total systemic vascular resistance was 2159.4 ± 523.5 dyn·s/cm5 before fluid administration. The SV-Vigileo was significantly higher than the SV-TEE both before (68.8 ± 15.9 vs. 57.0 ± 11.0 ml, P < 0.001) and after (73.0 ± 14.8 vs. 64.9 ± 12.2 ml, P = 0.003) fluid administration. During pneumoperitoneum combined with the Trendelenburg position, Bland-Altman analysis for repeated measures showed a 53.8% of percentage error between the SV-Vigileo and the SV-TEE. Four-quadrant plot (69.2% of a concordance rate) and polar plot analysis (20.6° of a mean polar angle, 16.4° of the SD of a polar angle, and ±51.5° of a radial sector containing 95% of the data points) did not indicate a good trending ability of the FloTrac/Vigileo™ system. CONCLUSIONS: The third-generation FloTrac/Vigileo™ system may not be useful in patients undergoing laparoscopic surgery, based on unreliable performance in measuring the stroke volume and in tracking changes in the stroke volume after fluid administration during pneumoperitoneum combined with the Trendelenburg position.

Effect of Tracheal Cuff Shape on Intracuff Pressure Change During Robot-Assisted Laparoscopic Surgery: The Tapered-Shaped Cuff Tube Versus the Cylindrical-Shaped Cuff Tube.

BACKGROUND: Although the cuff of tracheal tubes can reduce airflow leakage and prevent aspiration, excessive intracuff pressure can cause tracheal mucosal injury. Robot-assisted laparoscopic surgery (RALS) can increase intracuff pressure by the Trendelenburg position and pneumoperitoneum. The aim of our current study was to investigate the effect of tracheal cuff shape on the intracuff pressure increase by comparing two different-shaped cuffs during RALS. MATERIALS AND METHODS: Ninety-eight patients undergoing RALS were allocated randomly into two groups (tapered-shaped cuff [TSC] and cylindrical-shaped cuff [CSC] groups). The intracuff pressure was measured at nine specific time points: after intubation, immediately after surgical preparation (Trendelenburg position with CO2 insufflation), at 5, 10, 15, 30, 60, and 90 minutes after surgical preparation, and at the end of surgery. Postintubation airway symptoms were measured by assessing sore throat, hoarseness, and excessive cough 1 hour after postanesthesia care unit admission. RESULTS: Intracuff pressure significantly increased during surgery in both groups. The trend of intracuff pressure change decreased in the TSC group compared with the CSC group, although no statistically significant changes were found (P=.450). Also, there were no statistically significant differences in the postintubation airway symptom between the two groups. CONCLUSIONS: The TSC tube has a tendency to decrease intracuff pressure change compared with the CSC tube during RALS. However, neither of them was beneficial in preventing intraoperative intracuff pressure increase during RALS.

Pleiotrophin inhibits melanogenesis via Erk1/2-MITF signaling in normal human melanocytes.

Pleiotrophin (PTN) is a secreted heparin-binding protein that is involved in various biological functions of cell growth and differentiation. Little is known about the effects of PTN on the melanocyte function and skin pigmentation. In this study, we investigated whether PTN would affect melanogenesis. PTN was expressed in melanocytes and fibroblasts of human skin. Transfection studies revealed that PTN decreased melanogenesis, probably through MITF degradation via Erk1/2 activation in melanocytes. The inhibitory action of PTN in pigmentation was further confirmed in ex vivo cultured skin and in the melanocytes cocultured with fibroblasts. These findings suggest that PTN is a crucial factor for the regulation of melanogenesis in the skin.