Factors to consider during anesthesia in patients undergoing preemptive kidney transplantation: a propensity-score matched analysis.

BACKGROUND: International guidelines have recommended preemptive kidney transplantation (KT) as the preferred approach, advocating for transplantation before the initiation of dialysis. This approach is advantageous for graft and patient survival by avoiding dialysis-related complications. However, recipients of preemptive KT may undergo anesthesia without the opportunity to optimize volume status or correct metabolic disturbances associated with end-stage renal disease. In these regard, we aimed to investigate the anesthetic events that occur more frequently during preemptive KT compared to nonpreemptive KT. METHODS: This is a single-center retrospective study. Of the 672 patients who underwent Living donor KT (LDKT), 388 of 519 who underwent nonpreemptive KT were matched with 153 of 153 who underwent preemptive KT using propensity score based on preoperative covariates. The primary outcome was intraoperative hypotension defined as area under the threshold (AUT), with a threshold set at a mean arterial blood pressure below 70 mmHg. The secondary outcomes were intraoperative metabolic acidosis estimated by base excess and serum bicarbonate, electrolyte imbalance, the use of inotropes or vasopressors, intraoperative transfusion, immediate graft function evaluated by the nadir creatinine, and re-operation due to bleeding. RESULTS: After propensity score matching, we analyzed 388 and 153 patients in non-preemptive and preemptive groups. The multivariable analysis revealed the AUT of the preemptive group to be significantly greater than that of the nonpreemptive group (mean ± standard deviation, 29.7 ± 61.5 and 14.5 ± 37.7, respectively, P = 0.007). Metabolic acidosis was more severe in the preemptive group compared to the nonpreemptive group. The differences in the nadir creatinine value and times to nadir creatinine were statistically significant, but clinically insignificant. CONCLUSION: Intraoperative hypotension and metabolic acidosis occurred more frequently in the preemptive group during LDKT. These findings highlight the need for anesthesiologists to be prepared and vigilant in managing these events during surgery.

Continuous Titration of Inspired Oxygen Using Oxygen Reserve Index to Decrease Oxygen Exposure During One-Lung Ventilation: A Randomized Controlled Trial.

BACKGROUND: A high fraction of inspired oxygen (Fio2) is administered during one-lung ventilation (OLV). However, a high Fio2 is not physiologic and may lead to various complications. We hypothesized that continuous titration of Fio2 using the oxygen reserve index (ORI) reduces oxygen exposure compared to conventional management during OLV. METHODS: In this randomized, double-blinded trial, patients undergoing thoracic surgery were assigned to an ORI (n = 64) or a control group (n = 60). In the ORI group, ORI was continuously displayed using multiwavelength pulse co-oximetry (Masimo) between 0 and 1 (0, no reserve; 1, maximum reserve), and Fio2 was titrated for a target ORI of 0.21 at 5-minute intervals during OLV. In the control group, Fio2 was adjusted using arterial blood gas analysis measured at 15 minutes after OLV initiation. The primary end point was the time-weighted average Fio2 during OLV. RESULTS: Overall, time-weighted average Fio2 did not differ between the groups (control versus ORI: median [interquartile range], 0.87 [0.73-1.00] vs 0.82 [0.68-0.93]; P = .09). However, in a subgroup analysis, the ORI group reduced time-weighted average Fio2 after pulmonary vascular ligation compared to the control group (control versus ORI: median [interquartile range], 0.75 [0.70-1.00] vs 0.72 [0.59-0.89]; P = .0261). The incidence of intraoperative hypoxia (arterial oxygen saturation [Spo2] <94%; control versus ORI: 32% [19/60; 95% confidence interval (CI), 20-45] vs 19% [12/64; 95% CI, 10-31]; P = .09), and postoperative complications within the first 7 days did not differ between the groups. CONCLUSIONS: ORI-guided continuous Fio2 titration does not reduce overall oxygen exposure during OLV.

One-Year Recipient Morbidity of Liver Transplantation Using Pure Laparoscopic Versus Open Living Donor Right Hepatectomy: Propensity Score Analysis.

Donor safety and graft results of pure laparoscopic living donor right hepatectomy (LLDRH) have previously been compared with those of open living donor right hepatectomy (OLDRH). However, the clinical outcomes of recipients at 1-year follow-up have never been accurately compared. We aimed to compare 1-year outcomes of recipients of living donor right liver transplantation (LRLT) using pure LLDRH and OLDRH. From May 2013 to May 2017, 197 consecutive recipients underwent LRLT. Donor hepatectomies were performed either by OLDRH (n = 127) or pure LLDRH (n = 70). After propensity score matching, 53 recipients were included in each group for analysis. The clinical outcomes at 1-year follow-up were compared between the 2 groups. The primary outcome was recipient death or graft failure during the 1-year follow-up period. In the propensity-matched analysis, the incidence of death or graft failure during the 1-year follow-up period was not different between the 2 groups (3.8% versus 5.7%; odds ratio [OR], 1.45; 95% confidence interval [CI], 0.24-8.95; P = 0.69). However, the composite of Clavien-Dindo 3b-5 complications was more frequent in the pure LLDRH group (OR, 2.62; 95% CI, 1.15-5.96; P = 0.02). In conclusion, although pure LLDRH affords a comparable incidence of fatal complications in recipients, operative complications may increase at the beginning of the program. The safety of the recipients should be confirmed to accept pure LLDRH as a feasible option.

Living Donor Liver Transplantation for an Infant Having Tracheostomy and Subglottic Stenosis: A Case Report.

BACKGROUND: It is uncommon to perform liver transplantation for patients with end-stage liver disease having tracheostomy. Usually, the tracheostomy cannula is changed to an oral endotracheal tube (ETT) before operation because ETT is easy to handle during operation. If routine oral ETT insertion is difficult, we should seek other solutions. CASE DESCRIPTION: We report a successful conversion from tracheostomy tube to ETT in a patient with subglottic stenosis. The patient was an 8-month-old infant who was scheduled for living donor liver transplantation due to acute hepatic failure. The original plan was to convert the tracheostomy tube to oral ETT, which failed due to aggravation of subglottic stenosis. An otolaryngologist performed balloon dilatation surgery, and ETT was successfully intubated. Owing to a multidisciplinary approach, the surgery was successfully performed without fatal adverse events, and the patient was later discharged with a tracheostomy. CONCLUSIONS: It is unusual for pediatric patients with tracheostomy tubes to undergo major surgeries like liver transplantation. We hope that this case of successful anesthetic management based on a multidisciplinary approach suggests new ideas to anesthesiologists seeking safe anesthesia.

Safety of hydroxyzine in the sedation of pediatric dental patients.

Hydroxyzine is one of the most popular oral sedatives used in pediatric dentistry. This study aimed to investigate the safety and possible side effects of sedation using hydroxyzine in pediatric dentistry. "Hydroxyzine," "Dental sedation," "Child," and "Safety" and their associated synonyms were searched using the Cochrane Library, Embase, PubMed, KISS, KMBASE, and KoreaMed databases. Academic information and portals of DBpia and RISS were also perused. Altogether, 340 papers were found, among which a total of 24 papers were selected according to the detailed criteria. Nine studies used hydroxyzine as monotherapy, and 10 studies compared its safety when hydroxyzine used as multitherapy. In addition, seven studies employed a drug regimen wherein hydroxyzine was one of the components. All these studies revealed that the adverse events specific to hydroxyzine usage were drowsiness and dryness of the mouth, and that there were respiratory complications due to a synergistic reaction of hydroxyzine. Although classified as a histamine blocker, hydroxyzine with its sedative, antiemetic, anticonvulsant, and anticholinergic properties is an oral sedative available without serious adverse events, If the proper dosage of the drug is used and its synergistic effects with other drugs are ascertained in the route of administration.

The impact of pulmonary function tests on early postoperative complications in open lung resection surgery: an observational cohort study.

We investigated whether pulmonary function tests (PFTs) can predict pulmonary complications and if they are, to find new cutoff values in current open lung resection surgery. In this observational study, patients underwent open lung resection surgery at a tertiary hospital were analyzed (n = 1544). Various PFTs were tested by area under the receiver-operating characteristic curve (AUCROC) to predict pulmonary complications until 30 days postoperatively. In results, PFTs were generally not effective to predict pulmonary complications (AUCROC: 0.58-0.66). Therefore, we could not determine new cutoff values, and used previously reported cutoffs for post-hoc analysis [predicted postoperative forced expiratory volume in one second (ppoFEV1) < 40%, predicted postoperative diffusing capacity for carbon monoxide (ppoDLCO) < 40%]. In multivariable analysis, old age, male sex, current smoker, intraoperative transfusion and use of inotropes were independent risk factors for pulmonary complications (model 1: AUCROC 0.737). Addition of ppoFEV1 or ppoDLCO < 40% to model 1 did not significantly increase predictive capability (model 2: AUCROC 0.751, P = 0.065). In propensity score-matched subgroups, patients with ppoFEV1 or ppoDLCO < 40% showed higher rates of pulmonary complications [13% (21/160) vs. 24% (38/160), P = 0.014], but no difference in in-hospital mortality [3% (8/241) vs. 6% (14/241), P = 0.210] or mean survival duration [61 (95% CI 57-66) vs. 65 (95% CI 60-70) months, P = 0.830] compared to patients with both > 40%. In conclusion, PFTs themselves were not effective predictors of pulmonary complications. Decision to proceed with surgical resection of lung cancer should be made on an individual basis considering other risk factors and the patient's goals.

Application of sevoflurane inhalation sedation in dental treatment: a mini review.

Sevoflurane is familiar to anesthesiologists as an inhaled anesthetic to induce and maintain anesthesia; however, it has not been widely used for sedation. Recently, the use of sevoflurane for inhalational sedation has been increasing. Moreover, in Korea, the use of sevoflurane for conscious or deep sedation in dental care for children and the disabled is increasing, primarily by dental anesthesiologists. In this article, we reviewed a sedation method using sevoflurane.

Nonsustained ventricular tachycardia during outpatient anesthesia: a case report.

During the perioperative period, anesthesiologists frequently observe cardiac tachyarrhythmia. Ventricular tachycardia is very rare in non-cardiac surgeries. However, it can be fatal when it occurs. Therefore, anesthesiologists should be watchful so as to not to miss ventricular tachycardia and take the appropriate steps to manage it promptly. We present a case, with a review of related literature, in which a non-sustained ventricular tachycardia was observed in a patient who visited the hospital for dental treatment.

Awake craniotomy using a high-flow nasal cannula with oxygen reserve index monitoring - A report of two cases.

BACKGROUND: Awake craniotomy is a well-tolerated procedure for the resection of brain tumors residing within or close to the eloquent cortical areas. Monitored anesthesia care (MAC) is a dominant anesthetic approach for awake craniotomy; however, it is associated with inherent challenges such as desaturation and hypercapnia, which may lead to various complications. The prevention of respiratory insufficiency is important for successful awake craniotomy. As measures to avoid respiratory depression, the use of high-flow nasal cannula (HFNC) can improve patient oxygenation and monitor the monitoring the oxygen reserve index (ORi) can detect hypoxia earlier. CASE: We report two cases of awake craniotomy with MAC using HFNC and ORi. We adjusted the fraction of inspired oxygen of the HFNC according to the ORi level. The patient underwent successful awake craniotomy without a desaturation event or additional airway intervention. CONCLUSIONS: Combined HFNC and ORi monitoring may provide adequate oxygen reserves in patients undergoing awake craniotomy.

Comparison of Respiratory Effects between Dexmedetomidine and Propofol Sedation for Ultrasound-Guided Radiofrequency Ablation of Hepatic Neoplasm: A Randomized Controlled Trial.

Patient's cooperation and respiration is necessary in percutaneous radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC). We compared the respiratory patterns of dexmedetomidine and propofol sedation during this procedure. Participants were randomly allocated into two groups: the continuous infusions of dexmedetomidine-remifentanil (DR group) or the propofol-remifentanil (PR group). We measured the tidal volume for each patient's respiration during one-minute intervals at five points and compared the standard deviation of the tidal volumes (SDvt) between the groups. Sixty-two patients completed the study. SDvt at 10 min was not different between the groups (DR group, 108.58 vs. PR group, 149.06, p = 0.451). However, SDvt and end-tidal carbon dioxide (EtCO2) level of PR group were significantly increased over time compared to DR group (p = 0.004, p = 0.021; ß = 0.14, ß = -0.91, respectively). Heart rate was significantly decreased during sedation in DR group (p < 0.001, ß = -2.32). Radiologist satisfaction was significantly higher, and the incidence of apnea was lower in DR group (p = 0.010, p = 0.009, respectively). Compared with propofol-remifentanil, sedation using dexmedetomidine-remifentanil provided a lower increase of the standard deviation of tidal volume and EtCO2, and also showed less apnea during RFA of HCC.

Predictive Value of the Phase Angle for Analgesic Efficacy in Lumbosacral Transforaminal Block.

The mechanism of low back and leg pain involves mixed neuropathic and nociceptive components. Spinal neuropathic pain is related to increased levels of inflammatory cytokines and disrupted and increased permeability of the blood-spinal cord barrier, originally composed of tight junctions of capillary endothelial cells surrounded by lamina. The phase angle (PA) estimates cell membrane integrity using bioelectrical impedance analysis. We evaluated the predictive value of the PA for analgesic efficacy in lumbosacral transforaminal block. We retrospectively collected data from 120 patients receiving transforaminal blocks for lumbosacral radicular pain and assessed the PA before and 5 min following the block. Responders (group R) and non-responders (group N) were defined by ≥50% and <50% pain reduction, respectively, on a numerical rating scale, 30 min following the block; clinical data and the PA were compared. Among the 109 included patients, 50 (45.9%) and 59 (54.1%) had ≥50% and <50% pain reduction, respectively. In group N, the PA change ratio showed 88.1% specificity, 32.0% sensitivity, and 62.4% accuracy; a ratio of <0.087 at 5 min following the block predicted non-response. A PA change ratio of <0.087 at 5 min following lumbar transforaminal blocks predicted non-responders with high specificity.

Preoperative 2D-echocardiographic assessment of pulmonary arterial pressure in subgroups of liver transplantation recipients.

BACKGROUND: The clinical efficacy of preoperative 2D-echocardiographic assessment of pulmonary arterial pressure (PAP) has not been evaluated fully in liver transplantation (LT) recipients. METHODS: From October 2010 to February 2017, a total of 344 LT recipients who underwent preoperative 2D-echocardiography and intraoperative right heart catheterization (RHC) was enrolled and stratified according to etiology, disease progression, and clinical setting. The correlation of right ventricular systolic pressure (RVSP) on preoperative 2D-echocardiography with mean and systolic PAP on intraoperative RHC was evaluated, and the predictive value of RVSP > 50 mmHg to identify mean PAP > 35 mmHg was estimated. RESULTS: In the overall population, significant but weak correlations were observed (R = 0.27; P < 0.001 for systolic PAP, R = 0.24; P < 0.001 for mean PAP). The positive and negative predictive values of RVSP > 50 mmHg identifying mean PAP > 35 mmHg were 37.5% and 49.9%, respectively. In the subgroup analyses, correlations were not significant in recipients of deceased donor type LT (R = 0.129; P = 0.224 for systolic PAP, R = 0.163; P = 0.126 for mean PAP) or in recipients with poorly controlled ascites (R = 0.215; P = 0.072 for systolic PAP, R = 0.21; P = 0.079 for mean PAP). CONCLUSIONS: In LT recipients, the correlation between RVSP on preoperative 2D-echocardiography and PAP on intraoperative RHC was weak; thus, preoperative 2D-echocardiography might not be the optimal tool for predicting intraoperative PAP. In LT candidates at risk of pulmonary hypertension, RHC should be considered.

Effects of lowering inspiratory oxygen fraction during microvascular decompression on postoperative gas exchange: A pre-post study.

BACKGROUND: Despite many previous studies, the optimal oxygen fraction during general anesthesia remains controversial. This study aimed to evaluate the effects of lowering intraoperative fraction of inspired oxygen on postoperative gas exchange in patients undergoing microvascular decompression (MVD). METHODS: We conducted a pre-post study to compare postoperative gas exchange with different intraoperative oxygen fractions. From April 2010 to June 2017, 1456 consecutive patients who underwent MVD were enrolled. Starting in January 2014, routine oxygen fraction was lowered from 1.0 to 0.3 during anesthetic induction/awakening and from 0.5 to 0.3 during anesthetic maintenance. Postoperative gas exchange, presented as the minimum value of PaO2/FIO2 ratio within 48 hours, were compared along with adverse events. RESULTS: Among 1456 patients, 623 (42.8%) patients were stratified into group H (high FIO2) and 833 (57.2%) patients into group L (low FIO2). Intraoperative positive end-expiratory pressure was used in 126 (15.1%) patients in group H and 90 (14.4%) patients in group L (p = 0.77).The minimum value of PaO2/ FIO2 ratio within 48 hours after surgery was significantly greater in the group L (226.13 vs. 323.12; p < 0.001) without increasing any adverse events. CONCLUSION: In patients undergoing MVD, lowering routine FIO2 and avoiding 100% O2 improved postoperative gas exchange.