Visceral Adipose Tissue Reduction Measured by Deep Neural Network Architecture Improved Reflux Esophagitis Endoscopic Grade.

INTRODUCTION: Visceral obesity is a risk factor for reflux esophagitis (RE). We investigated the risk of RE according to visceral adipose tissue (VAT) measured by deep neural network architecture using computed tomography (CT) and evaluated the longitudinal association between abdominal adipose tissue changes and the disease course of RE. METHODS: Individuals receiving health checkups who underwent esophagogastroduodenoscopy (EGD) and abdominal CT at Seoul National University Healthcare System Gangnam Center between 2015 and 2016 were included. Visceral and subcutaneous adipose tissue areas and volumes were measured using a deep neural network architecture and CT. The association between the abdominal adipose tissue area and volume and the risk of RE was evaluated. Participants who underwent follow-up EGD and abdominal CT were selected; the effects of changes in abdominal adipose tissue area and volume on RE endoscopic grade were investigated using Cox proportional hazards regression. RESULTS: We enrolled 6,570 patients who underwent EGD and abdominal CT on the same day. RE was associated with male sex, hypertension, diabetes, excessive alcohol intake, current smoking status, and levels of physical activity. The VAT area and volume increased the risk of RE dose-dependently. A decreasing VAT volume was significantly associated with improvement in RE endoscopic grade (hazard ratio: 3.22, 95% confidence interval: 1.82-5.71). Changes in subcutaneous adipose tissue volume and the disease course of RE were not significantly correlated. DISCUSSION: Visceral obesity is strongly associated with RE. VAT volume reduction was prospectively associated with improvement in RE endoscopic grade dose-dependently. Visceral obesity is a potential target for RE treatment.

Relationship between preinduction electroencephalogram patterns and propofol sensitivity in adult patients.

PURPOSE: To determine the precise induction dose, an objective assessment of individual propofol sensitivity is necessary. This study aimed to investigate whether preinduction electroencephalogram (EEG) data are useful in determining the optimal propofol dose for the induction of general anesthesia in healthy adult patients. METHODS: Seventy healthy adult patients underwent total intravenous anesthesia (TIVA), and the effect-site target concentration of propofol was observed to measure each individual's propofol requirements for loss of responsiveness. We analyzed preinduction EEG data to assess its relationship with propofol requirements and conducted multiple regression analyses considering various patient-related factors. RESULTS: Patients with higher relative delta power (ρ = 0.47, p < 0.01) and higher absolute delta power (ρ = 0.34, p = 0.01) required a greater amount of propofol for anesthesia induction. In contrast, patients with higher relative beta power (ρ = -0.33, p < 0.01) required less propofol to achieve unresponsiveness. Multiple regression analysis revealed an independent association between relative delta power and propofol requirements. CONCLUSION: Preinduction EEG, particularly relative delta power, is associated with propofol requirements during the induction of general anesthesia. The utilization of preinduction EEG data may improve the precision of induction dose selection for individuals.

Relationships between common carotid artery blood flow and anesthesia, pneumoperitoneum, and head-down tilt position: a linear mixed-effect analysis.

This study investigated the effects of pneumoperitoneum and the head-down tilt position on common carotid artery (CCA) blood flow in surgical patients. METHODS: This prospective observational study included 20 patients who underwent gynecological surgery. CCA blood flow was measured using Doppler ultrasound at four-time points: awake in the supine position [T1], 3 min after anesthesia induction in the supine position [T2], 3 min after pneumoperitoneum in the supine position [T3], and 3 min after pneumoperitoneum in the head-down tilt position [T4]. Hemodynamic and respiratory parameters were also recorded at each time point. Linear mixed-effect analyses were performed to compare CCA blood flow across the time points and assess its relationship with hemodynamic parameters. RESULTS: Compared with T1, CCA blood flow decreased significantly at T2 (345.4 [288.0-392.9] vs. 293.1 [253.0-342.6], P = 0.048). CCA blood flow were also significantly lower at T3 and T4 compared with T1 (345.4 [288.0-392.9] vs. 283.6 [258.8-307.6] and 287.1 [242.1-321.4], P = 0.005 and 0.016, respectively). CCA blood flow at T3 and T4 did not significantly differ from that at T2. Changes in CCA blood flow were significantly associated with changes in cardiac index and stroke volume index (P = 0.011 and 0.024, respectively). CONCLUSION: CCA blood flow was significantly decreased by anesthesia induction. Inducing pneumoperitoneum, with or without the head-down tilt position, did not further decrease CCA blood flow if the cardiac index remained unchanged. The cardiac index and stroke volume index were significantly associated with CCA blood flow. CLINICAL TRIAL REGISTRATION: Clinicaltrials.gov (NCT04233177, January 18, 2020).

Risk prediction models incorporating institutional case volume for mortality after hip fracture surgery in the elderly.

INTRODUCTION: While higher institutional case volume is associated with better postoperative outcomes in various types of surgery, institutional case volume has been rarely included in risk prediction models for surgical patients. This study aimed to develop and validate the predictive models incorporating institutional case volume for predicting in-hospital mortality and 1-year mortality after hip fracture surgery in the elderly. MATERIALS AND METHODS: Data for all patients (≥ 60 years) who underwent surgery for femur neck fracture, pertrochanteric fracture, or subtrochanteric fracture between January 2008 and December 2016 were extracted from the Korean National Health Insurance Service database. Patients were randomly assigned into the derivation cohort or the validation cohort in a 1:1 ratio. Risk prediction models for in-hospital mortality and 1-year mortality were developed in the derivation cohort using the logistic regression model. Covariates included age, sex, type of fracture, type of anaesthesia, transfusion, and comorbidities such as hypertension, diabetes, coronary artery disease, chronic kidney disease, cerebrovascular disease, and dementia. Two separate models, one with and the other without institutional case volume as a covariate, were constructed, evaluated, and compared using the likelihood ratio test. Based on the models, scoring systems for predicting in-hospital mortality and 1-year mortality were developed. RESULTS: Analysis of 196,842 patients showed 3.6% in-hospital mortality (7084/196,842) and 15.42% 1-year mortality (30,345/196,842). The model for predicting in-hospital mortality incorporating the institutional case volume demonstrated better discrimination (c-statistics 0.692) compared to the model without the institutional case volume (c-statistics 0.688; likelihood ratio test p value < 0.001). The performance of the model for predicting 1-year mortality was also better when incorporating institutional case volume (c-statistics 0.675 vs. 0.674; likelihood ratio test p value < 0.001). CONCLUSIONS: The new institutional case volume incorporated scoring system may help to predict in-hospital mortality and 1-year mortality after hip fracture surgery in the elderly population.

Effect of remifentanil on post-operative analgesic consumption in patients undergoing shoulder arthroplasty after interscalene brachial plexus block: a randomized controlled trial.

PURPOSE: Remifentanil is useful in balanced anesthesia; however, there is concern regarding opioid-induced hyperalgesia. The effect of remifentanil on rebound pain, characterized by hyperalgesia after peripheral nerve block has rarely been studied. This study evaluated whether intraoperative remifentanil infusion may increase postoperative analgesic requirement in patients receiving preoperative interscalene brachial plexus block (IBP). METHODS: Sixty-eight patients undergoing arthroscopic shoulder surgery under general anesthesia were randomly allocated to remifentanil (R) or control (C) group. Preoperative IBP with 0.5% ropivacaine 15 mL was performed in all patients. Intraoperative remifentanil was administered only in the R group. Postoperative pain was controlled using intravenous patient-controlled analgesia (IV-PCA) and rescue analgesics. The primary outcome was the dosage of fentanyl-nefopam IV-PCA infused over 24 h postoperatively. The secondary outcomes included the numeric rating scale (NRS) score recorded at 4-h intervals over 24 h, amount of rescue analgesics and total postoperative analgesics used over 24 h, occurrence of intraoperative hypotension, postoperative nausea and vomiting (PONV) and delirium. RESULTS: The dosage of fentanyl-nefopam IV-PCA was significantly less in C group than R group for postoperative 24 h. Fentanyl 101 [63-158] (median [interquartile range]) µg was used in the C group, while fentanyl 161 [103-285] µg was used in the R group (median difference 64 µg, 95% CI 10-121 µg, P = 0.02). Nefopam 8.1 [5.0-12.6] mg was used in the C group, while nefopam 12.9 [8.2-22.8] mg was used in the R group (median difference 5.1 mg, 95% CI 0.8-9.7 mg, P = 0.02). The total analgesic consumption: the sum of PCA consumption and administered rescue analgesic dose, converted to morphine milligram equivalents, was higher in the R group than C group (median difference 10.9 mg, 95% CI 3.0-19.0 mg, P = 0.01). The average NRS score, the incidence of PONV and delirium, were similar in both groups. The incidence of intraoperative hypotension was higher in R group than C group (47.1% vs. 20.6%, P = 0.005). CONCLUSIONS: Remifentanil administration during arthroscopic shoulder surgery in patients undergoing preoperative IBP increased postoperative analgesic consumption.

Optimal angle of needle insertion for spinal anesthesia in patients with spondylolisthesis: an ultrasonographic study.

BACKGROUND: Spondylolisthesis is a common degenerative spinal deformity. At the level of spondylolisthesis, the anatomy of the interlaminar space may differ from normal spine, in which case optimal angle of the needle insertion for spinal anesthesia may change. This study compared the optimal angle of needle insertion during spinal anesthesia in patients with and without lumbar spondylolisthesis using ultrasound. METHODS: We recruited 40 patients, 20 with and 20 without lumbar spondylolisthesis (group S and N, respectively). Ultrasonography was performed in the transverse midline and parasagittal oblique views at the spondylolisthesis level and the adjacent upper level. We measured the probe application angle with the longest interlaminar height of the ligamentum flavum-dura mater complex (LFD), depth from the skin to the LFD, depth from the skin to the anterior complex, and intrathecal space width. A positive angle represented a cephalad angulation. RESULTS: The optimal needle insertion angle in the transverse midline view at the spondylolisthesis level was (-) 2.7 ± 3.4° in group S and 0.8 ± 2.5° in group N (P [Formula: see text] 0.001). In the parasagittal oblique view, it was (-) 2.7 ± 4.5° in group S and 1.0 ± 3.2° in group N (P = 0.004). There were no between-group differences in the angles at the upper level, with all cephalad angles in both views. Other ultrasound image data were comparable between groups. CONCLUSION: In patients with spondylolisthesis, caudad angulation of the spinal needle can aid successful spinal puncture at spondylolisthesis level, both in the midline and paramedian approaches. TRIAL REGISTRATION: www.ClinicalTrials.gov ( NCT04426916 ); registered 11 June 2020.

Effect of Sedatives on In-hospital and Long-term Mortality of Critically Ill Patients Requiring Extended Mechanical Ventilation for ≥ 48 Hours.

BACKGROUND: The purpose of this study was to assess the correlation between sedatives and mortality in critically ill patients who required mechanical ventilation (MV) for ≥ 48 hours from 2008 to 2016. METHODS: We conducted a nationwide retrospective cohort study using population-based healthcare reimbursement claims database. Data from adult patients (aged ≥ 18) who underwent MV for ≥ 48 hours between 2008 and 2016 were identified and extracted from the National Health Insurance Service database. The benzodiazepine group consisted of patients who were administered benzodiazepines for sedation during MV. All other patients were assigned to the non-benzodiazepine group. RESULTS: A total of 158,712 patients requiring MV for ≥ 48 hours were admitted in 55 centers in Korea from 2008 to 2016. The benzodiazepine group had significantly higher in-hospital and one-year mortality compared to the non-benzodiazepine group (37.0% vs. 34.3%, 55.0% vs. 54.4%, respectively). Benzodiazepine use decreased from 2008 to 2016, after adjusting for age, sex, and mean Elixhauser comorbidity index in the Poisson regression analysis (incidence rate ratio, 0.968; 95% confident interval, 0.954-0.983; P < 0.001). Benzodiazepine use, older age, lower case volume (≤ 500 cases/year), chronic kidney disease, and higher Elixhauser comorbidity index were common significant risk factors for in-hospital and one-year mortality. CONCLUSION: In critically ill patients undergoing MV for ≥ 48 hour, the use of benzodiazepines for sedation, older age, and chronic kidney disease were associated with higher in-hospital mortality and one-year mortality. Further studies are needed to evaluate the impact of benzodiazepines on the mortality in elderly patients with chronic kidney disease requiring MV for ≥ 48 hours.

Ultrasound-guided versus conventional lung recruitment manoeuvres in laparoscopic gynaecological surgery: A randomised controlled trial.

BACKGROUND: Pneumoperitoneum and steep Trendelenburg position promote the formation of pulmonary atelectasis during laparoscopic gynaecological surgery. OBJECTIVE: To determine whether lung ultrasound-guided alveolar recruitment manoeuvres could reduce peri-operative atelectasis compared with conventional recruitment manoeuvres during laparoscopic gynaecological surgery. DESIGN: Randomised controlled trial. SETTING: Tertiary hospital, Republic of Korea, from August 2018 to January 2019. PATIENTS: Adult patients scheduled for laparoscopic gynaecological surgery under general anaesthesia. INTERVENTION: Forty patients were randomised to receive either ultrasound-guided recruitment manoeuvres (manual inflation until no visibly collapsed area was seen with lung ultrasonography; intervention group) or conventional recruitment manoeuvres (single manual inflation with 30 cmH2O pressure; control group). Recruitment manoeuvres were performed 5 min after induction and at the end of surgery in both groups. All patients received volume-controlled ventilation with a tidal volume of 8 ml kg-1 and a positive end-expiratory pressure of 5 cmH2O. MAIN OUTCOME MEASURES: The primary outcome was the lung ultrasound score at the end of surgery; a higher score indicates worse lung aeration. RESULTS: Lung ultrasound scores at the end of surgery were significantly lower in the intervention group compared with control group (median [IQR], 7.5 [6.5 to 8.5] versus 9.5 [8.5 to 13.5]; difference, -2 [95% CI, -4.5 to -1]; P = 0.008). The intergroup difference persisted in the postanaesthesia care unit (7 [5 to 8.8] versus 10 [7.3 to 12.8]; difference, -3 [95% CI, -5.5 to -1.5]; P = 0.005). The incidence of atelectasis was lower in the intervention group compared with control group at the end of surgery (35 versus 80%; P = 0.010) but was comparable in the postanaesthesia care unit (40 versus 55%; P = 0.527). CONCLUSIONS: The use of ultrasound-guided recruitment manoeuvres improves peri-operative lung aeration; these effects may persist in the postanaesthesia care unit. However, the long-term effects of ultrasound-guided recruitment manoeuvres on clinical outcomes should be the subject of future trials. TRIAL REGISTRATION: ClinicalTrials.gov (NCT03607240).

Efficacy of intra-operative administration of iron isomaltoside for preventing postoperative anaemia after total knee arthroplasty: A randomised controlled trial.

BACKGROUND: Postoperative anaemia is common after total knee arthroplasty (TKA). Emerging evidence shows the beneficial effects of peri-operative iron supplementation in patients at risk of postoperative anaemia. OBJECTIVE: To evaluate the efficacy of intra-operative administration of iron isomaltoside for the prevention of postoperative anaemia in patients undergoing TKA. DESIGN: Randomised, controlled, double-blind, parallel-group study. SETTING: A tertiary care teaching hospital; between 29 March 2018 and 16 April 2019. PATIENTS: Eighty-nine patients scheduled for unilateral TKA were included. INTERVENTION: Iron isomaltoside or placebo were administered intravenously over 30 min during surgical wound closure. MAIN OUTCOME MEASURES: The primary outcome measure was the incidence of anaemia at 30 days after TKA: anaemia was defined as haemoglobin less than 12 g dl-1 for female and less than 13 g dl-1 for male. RESULTS: In total, 89 patients were included in the final analysis (44 in the treatment group; 45 in the control group). The administered dose of iron isomaltoside in the treatment group was 1136 ±â€Š225 mg. The incidence of anaemia at 30 days after TKA was significantly lower in the treatment group (34.1%, 15/44) than that in the control group (62.2%, 28/45): relative risk 0.55 (95% confidence interval, 0.34 to 0.88), P = 0.008. Haemoglobin concentration, serum ferritin concentrations, and transferrin saturation were also significantly higher in the treatment group at 30 days after TKA. CONCLUSION: The intra-operative administration of iron isomaltoside effectively prevents postoperative anaemia in patients undergoing TKA, and thus it can be included in patient blood management protocols for reducing postoperative anaemia in these population. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT03470649.

Ultrasound-Assisted Versus Landmark-Guided Spinal Anesthesia in Patients With Abnormal Spinal Anatomy: A Randomized Controlled Trial.

BACKGROUND: Spinal anesthesia using a surface landmark-guided technique can be challenging in patients with anatomical alterations of the lumbar spine; however, it is unclear whether using ultrasonography can decrease the technical difficulties in these populations. We assessed whether an ultrasound-assisted technique could reduce the number of needle passes required for block success compared with the landmark-guided technique in patients with abnormal spinal anatomy. METHODS: Forty-four patients with abnormal spinal anatomy including documented lumbar scoliosis and previous spinal surgery were randomized to receive either surface landmark-guided or preprocedural ultrasound-assisted spinal anesthesia. All spinal procedures were performed by 1 of 3 experienced anesthesiologists. The primary outcome was the number of needle passes required for successful dural puncture. Secondary outcomes included the success rate on the first pass, total procedure time, periprocedural pain scores, and the incidences of radicular pain, paresthesia, and bloody tap during the neuraxial procedure. Intergroup difference in the primary outcome was assessed for significance using Mann-Whitney U test. RESULTS: The median (interquartile range [IQR; range]) number of needle passes was significantly lower in the ultrasound group than in the landmark group (ultrasound 1.5 [1-3 {1-5}]; landmark 6 [2-9.3 {1-15}]; P < .001). First-pass success was achieved in 11 (50.0%) and 2 (9.1%) patients in the ultrasound and landmark groups, respectively (P = .007). The total procedure time, defined as the sum of the time for identifying landmarks and performing spinal anesthesia, did not differ significantly between the 2 groups (ultrasound 141 seconds [115-181 seconds {101-336 seconds}]; landmark 146 seconds [90-295 seconds {53-404 seconds}]; P = .888). The ultrasound group showed lower periprocedural pain scores compared with the landmark group (ultrasound 3.5 [1-5 {0-7}]; landmark 5.5 [3-8 {0-9}]; P = .012). The incidences of complications during the procedure showed no significant differences between the 2 groups. CONCLUSIONS: For anesthesiologists with experience in neuraxial ultrasonography, the use of ultrasound significantly reduces the technical difficulties of spinal anesthesia in patients with abnormal spinal anatomy compared with the landmark-guided technique. Our results can lead to practical suggestions that encourage the use of neuraxial ultrasonography for spinal anesthesia in such patients.

Hydroxyethyl Starch 6% 130/0.4 in a Balanced Electrolyte Solution and Renal Function After Nephrectomy.

BACKGROUND: Although previous studies have reported nephrotoxicity associated with hydroxyethyl starch (HES), the long-term effect of HES on renal function after nephrectomy has rarely been reported. We evaluated the association between intraoperative HES administration and short- and long-term renal function after nephrectomy. METHODS: We retrospectively reviewed 1106 patients who underwent partial or radical nephrectomy. The patients were divided into 2 groups: patients who received (HES group) or did not receive 6% HES 130/0.4 intraoperatively (non-HES group). The primary outcome was new-onset chronic kidney disease (CKD) stage 3a (estimated glomerular filtration rate [eGFR] <60 mL/min/1.73 m) or higher or all-cause mortality during 60 months after surgery. Propensity score matching was performed to address baseline differences between the 2 groups. Renal survival determined by stage 3a and stage 5 CKD (eGFR <15 mL/min/1.73 m) or all-cause mortality were compared up to 60 months before and after matching. We compared postoperative acute kidney injury (AKI) and CKD upstaging in the matched cohort as secondary outcomes. Ordinal logistic regression and Cox proportional hazards regression analyses using inverse probability of treatment weighting were performed for postoperative AKI and our primary outcome, respectively. A subgroup analysis of partial nephrectomy was performed. RESULTS: Thirty percent of patients received HES intraoperatively. Balanced solution and 0.9% normal saline was administered during surgery in both groups. Renal survival was not significantly different between groups after matching (log-rank test P = .377 for our primary outcome, and P = .981 for stage 5 or all-cause mortality, respectively). In the matched cohort (HES group: n = 280, non-HES group: n = 280), the incidence of AKI or CKD upstaging at 1 year was not significantly different (AKI: n = 94, 33.6% in HES group versus n = 90, 32.1% in non-HES group; CKD upstaging: n = 132, 47.1% in HES group versus n = 122, 43.6% in non-HES group; odds ratio [OR], 1.16; 95% confidence interval [CI], 0.83-1.61; P = .396). Intraoperative HES administration was not associated with postoperative renal outcomes (AKI: OR, 0.97; 95% CI, 0.81-1.16; P = .723; CKD stage 3a or higher or all-cause mortality: hazard ratio, 1.01; 95% CI, 0.89-1.14; P = .920). Subgroup analysis yielded similar results. CONCLUSIONS: Intraoperative 6% HES 130/0.4 administration was not significantly associated with short- and long-term renal function or renal survival up to 5 years in patients undergoing partial or radical nephrectomy. However, wide CI including large harm effect precludes firm conclusion and inadequate assessment of safety cannot be ruled out by our results.

The cumulative duration of bispectral index less than 40 concurrent with hypotension is associated with 90-day postoperative mortality: a retrospective study.

BACKGROUND: The relationship between intraoperative low bispectral index (BIS) values and poor clinical outcomes has been controversial. Intraoperative hypotension is associated with postoperative complication. The purpose of this study was to investigate the influence of intraoperative low BIS values and hypotension on postoperative mortality in patients undergoing major abdominal surgery. METHODS: This retrospective study analyzed 1862 cases of general anesthesia. We collected the cumulative time of BIS values below 20 and 40 as well as electroencephalographic suppression and documented the incidences in which these states were maintained for at least 5 min. Durations of intraoperative mean arterial pressures (MAP) less than 50 mmHg were also recorded. Multivariable logistic regression was used to evaluate the association between suspected risk factors and postoperative mortality. RESULTS: Ninety-day mortality and 180-day mortality were 1.5 and 3.2% respectively. The cumulative time in minutes for BIS values falling below 40 coupled with MAP falling below 50 mmHg was associated with 90-day mortality (odds ratio, 1.26; 95% confidence interval, 1.04-1.53; P = .019). We found no association between BIS related values and 180-day mortality. CONCLUSIONS: The cumulative duration of BIS values less than 40 concurrent with MAP less than 50 mmHg was associated with 90-day postoperative mortality, not 180-day postoperative mortality.

Neutrophil/Lymphocyte Ratio in Patients Undergoing Noncardiac Surgery After Coronary Stent Implantation.

OBJECTIVE: Perioperative cell count-associated predictors, including the neutrophil/lymphocyte ratio (N/LR) and platelet/lymphocyte ratio (P/LR), are associated with poor clinical outcomes including myocardial injury. Study investigators aimed to examine the association among the perioperative N/LR, P/LR, and postoperative major adverse cardiovascular and cerebral events (MACCE) after noncardiac surgery in patients with drug-eluting stent (DES) insertion. DESIGN: Retrospective and observational. SETTING: Single university hospital. PARTICIPANTS: The study comprised 965 patients who underwent noncardiac surgery within 6 months after DES implantation. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Baseline perioperative clinical parameters, including N/LR and P/LR measured before surgery, immediately after surgery, and on postoperative day (POD) 1, were obtained. MACCE was defined as a composite of nonfatal myocardial infarction, coronary revascularization, nonhemorrhagic stroke, and pulmonary embolism within 1 month after surgery. Multivariate logistic regression analysis and propensity score matching were used to identify predictors of MACCE after surgery. MACCE occurred in 67 patients (6.9%) and was more common in patients with N/LR on POD 1 >4.3 (multivariable-adjusted odds ratio [OR] 2.03, 95% confidence interval [CI] 1.12-2.79; p = 0.040 and as a continuous N/LR [OR 1.17, 95% CI 1.08-1.27; p < 0.001]). This association was consistent after propensity score matching and was stronger when the antiplatelet agent was stopped before surgery (OR 3.02, 95% CI 2.14-4.48; p = 0.006 for stopping dual antiplatelet therapy). CONCLUSIONS: In patients undergoing noncardiac surgery within 6 months after DES implantation, elevated N/LR on POD 1 is independently associated with postoperative MACCE. Elevated postoperative N/LR as a marker of systemic inflammation may help to predict the development of MACCE in these high-risk patients.

The Hemodynamic Effect of Epinephrine-Containing Local Infiltration Analgesia After Tourniquet Deflation During Total Knee Arthroplasty: A Retrospective Observational Study.

BACKGROUND: Local infiltration analgesia (LIA) is widely used in patients undergoing total knee arthroplasty and often contains epinephrine for a prolonged analgesic effect and to reduce systemic absorption of the local anesthetic. This retrospective observational study investigated the hemodynamic effect of locally infiltrated epinephrine after deflation of the tourniquet during total knee arthroplasty. METHODS: We reviewed the electronic medical records of patients who underwent total knee arthroplasty between January 2017 and February 2018 at a tertiary care university hospital. Total knee arthroplasty was performed using a conventional technique with a pneumatic tourniquet. LIA consisted of ropivacaine, morphine sulfate, ketorolac, and methylprednisolone. The patients were grouped according to whether or not epinephrine was included in the LIA. The incidence of a hypertensive response (systolic blood pressure >160 mmHg or mean blood pressure >110 mmHg) after deflation of the tourniquet was compared between the 2 groups. RESULTS: A total of 452 patients had received LIA with (n = 188) or without (n = 264) epinephrine. A hypertensive response after deflation of the tourniquet was more common in patients who received LIA containing epinephrine (42/188 [22.3%]) than in those who received LIA without epinephrine (14/264 [5.3%], P < .001). However, the incidence of hypotension after deflation of the tourniquet was not significantly different between the 2 groups (P = .976). CONCLUSION: Because epinephrine-containing LIA can result in a hypertensive response after deflation of the tourniquet during total knee arthroplasty, it should be cautiously administered, especially in patients with cardiovascular comorbidities.

Total Intravenous Anesthesia versus Inhalation Anesthesia for Breast Cancer Surgery: A Retrospective Cohort Study.

BACKGROUND: The association between type of anesthesia used and recurrence of cancer remains controversial. This retrospective cohort study compared the influence of total IV anesthesia and inhalation anesthesia on the primary outcome of recurrence-free survival after breast cancer surgery. METHODS: The authors reviewed the electronic medical records of patients who had breast cancer surgery at a tertiary care teaching hospital between January 2005 and December 2013. The patients were grouped according to whether IV or inhalation anesthesia was used for surgery. Propensity score matching was used to account for differences in baseline characteristics. Kaplan-Meier survival curves were constructed to evaluate the influence of type of anesthesia on recurrence-free survival and overall survival. The risks of cancer recurrence and all-cause mortality were compared between each type of anesthesia. RESULTS: Of 7,678 patients who had breast cancer surgery during the study period, data for 5,331 patients were available for analysis (IV group, n = 3,085; inhalation group, n = 2,246). After propensity score matching, 1,766 patients remained in each group. Kaplan-Meier survival curves showed that there was no significant difference in recurrence-free survival or overall survival between the two groups, with 5-yr recurrence-free survival rates of 93.2% (95% CI, 91.9 to 94.5) in the IV group and 93.8% (95% CI, 92.6 to 95.1) in the inhalation group. Inhalation anesthesia had no significant impact on recurrence-free survival (hazard ratio, 0.96; 95% CI, 0.69 to 1.32; P = 0.782) or overall survival (hazard ratio, 0.96; 95% CI, 0.69 to 1.33, P = 0.805) when compared with total IV anesthesia. CONCLUSIONS: The authors found no association between type of anesthesia used and the long-term prognosis of breast cancer. The results of this retrospective cohort study do not suggest specific selection of IV or inhalation anesthesia for breast cancer surgery.

The effect of neck extension on success rate of blind intubation through Ambu® AuraGain™ laryngeal mask: a randomized clinical trial.

PURPOSE: Although the use of fibreoptic guidance is recommended for tracheal intubation through supraglottic airway devices, it can also be performed in a blind manner. Based on the previous finding that a fibreoptic view of the vocal cords was better in the extended neck position than in the neutral position, we hypothesized that neck extension can better facilitate blind intubation through the Ambu® AuraGain™ laryngeal mask than the neutral position. METHODS: Patients undergoing general anesthesia were randomly assigned to the extension group or the neutral group. After induction of anesthesia, the AuraGain™ was placed in the oropharynx, followed by blind intubation through the AuraGain™ in the assigned neck position within a maximum of two attempts. The primary outcome was successful blind intubation through the AuraGain™ in the first attempt. RESULTS: Of 168 adult patients screened, 124 patients were enrolled and 121 patients were included in the final analysis (extension group, n = 59; neutral group, n = 62). The incidence of successful blind intubation on the first attempt was significantly higher in the extension group than in the neutral group (68% vs. 47%, respectively; relative risk [RR], 1.45; 95% confidence interval [CI], 1.05 to 1.99; P = 0.02). The overall incidence of successful blind intubation was also significantly higher in the extension group than in the neutral group (71% vs 50%, respectively; RR, 1.42; 95% CI, 1.06 to 1.92; P = 0.02). The time required for successful blind intubation and the incidence of hoarseness, cough, or sore throat at 24 hr after extubation did not differ between groups. CONCLUSION: Neck extension can be used to facilitate blind intubation through the Ambu® AuraGain™ laryngeal mask. Considering the relatively high failure rate, blind intubation via the AuraGain™ should be used as an alternative, not as a first-line choice. TRIAL REGISTRATION: www.ClinicalTrials.gov (NCT03408431); registered 24 January 2018.

Safety margin for needle placement during lumbar plexus block: An anatomical study using magnetic resonance imaging.

PURPOSE: We aimed to provide anatomic characteristics of the lumbar plexus and a safety margin for needle placement during lumbar plexus block in adults. METHODS: Lumbar spine magnetic resonance images from 377 adults were reviewed. We determined the depth of the lumbar plexus from the needle insertion point for the modified traditional and Capdevila's approaches at the L4 and L5 levels. The relationship of age, height, and body weight with lumbar plexus depth, and the presence of the kidney on the transverse plane at the L4 level were assessed. RESULTS: The lumbar plexus was deeper at the L5 level than at the L4 level for both approaches (mean difference 3.2 mm [95% confidence interval (CI), 2.4 to 4.0] for the modified traditional approach; mean difference 4.4 mm [95% CI, 3.7 to 5.2] for Capdevila's approach). Eighty-six (22.8%) patients had an L4 transverse process shorter than 40 mm, which implies that the needle may not contact the L4 transverse process with the modified traditional approach. The mean (standard deviation) of safety margins for needle insertion, defined as the distance from the posterior aspect of the L4 transverse process to the anterior margin of the psoas muscle, were 45 (8) and 44 (6) mm, respectively for the modified traditional and Capdevila's approach (mean difference, 0.5 mm; 95% CI, -0.1 to 1.1]). The lumbar plexus depth for each approach at the L4 level was predicted using the following equations: Depth (mm) = 87.24 - 0.36 × height (cm) + 0.69 × weight (kg) for the modified traditional approach (r2 = 0.37) and Depth (mm) = 86.51 - 0.35 × height (cm) + 0.61 × weight (kg) for Capdevila's approach (r2 = 0.33). The kidney was observed at the L4 level in 60 (15.9%) patients, with higher incidence in patients over 70 yr and those shorter than 150 cm. CONCLUSION: The surface anatomic relations of the lumbar plexus found in this study may be useful for performing successful and safe lumbar plexus block.

RéSUMé: OBJECTIF: Nous avons cherché à fournir des données anatomiques du plexus lombaire et de la marge de sécurité pour le positionnement de l'aiguille au cours d'un bloc lombaire chez l'adulte. MéTHODES: Les images par résonance magnétique de la colonne vertébrale lombaire de 377 adultes ont été analysées. Nous avons déterminé la profondeur du plexus lombaire à partir du point d'insertion de l'aiguille pour les approches traditionnelle modifiée et de Capdevila aux niveaux L4 et L5. Les corrélations de l'âge, de la taille et du poids corporel avec la profondeur du plexus lombaire et la présence du rein sur le plan de l'apophyse transverse au niveau de L4 ont été évaluées. RéSULTATS: Le plexus lombaire était plus profond à l'étage L5 qu'à l'étage L4 pour les deux approches (différence moyenne : 3,2 mm [intervalle de confiance (IC) à 95 % : 2,4 à 4,0] pour l'approche traditionnelle modifiée; différence moyenne : 4,4 mm [IC à 95 % : 3,7 à 5,2] pour l'approche de Capdevila). Quatre-vingt-six patients (22,8 %) avaient l'apophyse transverse de L4 mesurant moins de 40 mm, ce qui implique que l'aiguille pourrait ne pas faire contact avec cette apophyse avec l'approche traditionnelle modifiée. Les marges de sécurité pour l'insertion de l'aiguille, définies comme étant la distance moyenne (écart-type) entre la face postérieure de l'apophyse transverse de L4 et la marge antérieure du muscle psoas, étaient de 45 (8) mm et 44 (6) mm pour, respectivement, l'approche traditionnelle modifiée et l'approche de Capdevila (différence des moyennes, 0,5 mm; IC à 95 % : −0,1 à 1,1). La profondeur du plexus lombaire pour chaque approche au niveau L4 a été prédite à l'aide des équations suivantes : Profondeur (mm) = 87,24 − 0,36 × taille (cm) + 0,69 × poids (kg) pour l'approche traditionnelle modifiée (r2 = 0,37) et Profondeur (mm) = 86,51 − 0,35 × taille (cm) + 0,61 × poids (kg) pour l'approche de Capdevila (r2 = 0,33). Le rein a été observé au niveau L4 chez 60 patients (15,9 %) avec une plus grande incidence chez les patients âgés de plus de 70 ans et chez ceux dont la taille était inférieure à 150 cm. CONCLUSION: Les rapports anatomiques de la surface du corps et du plexus lombaire identifiés dans cette étude peuvent contribuer à la réalisation d'un bloc lombaire efficace et sécuritaire.

Effect of different fraction of inspired oxygen on development of atelectasis in mechanically ventilated children: A randomized controlled trial.

BACKGROUND: The use of high fraction of inspired oxygen (FI O2 ) can cause direct pulmonary toxicity and pulmonary complications. The purpose of this study was to evaluate the effect of different FI O2 on development of intraoperative atelectasis in mechanically ventilated children using lung ultrasound. METHODS: In this randomized controlled, patient- and sonographer-blinded trial, 86 children (≤6 years) undergoing noncardiac surgery were allocated into a low (n = 43) or high (n = 43) FI O2 group. The low FI O2 group consistently received 30% air-oxygen mixture during preoxygenation, ultrasound-guided recruitment maneuver, and mechanical ventilation. The high FI O2 group received 100% oxygen during preoxygenation and ultrasound-guided recruitment maneuver and 60% air-oxygen mixture during mechanical ventilation. Positive end-expiratory pressure of 5 cm H2 O was applied in both groups. Lung ultrasound was performed one minute after the start of mechanical ventilation and at the end of surgery in both groups. Primary outcome was significant atelectasis incidence (consolidation score of ≥2 in any region) on the postoperative lung ultrasound. Secondary outcomes included significant atelectasis incidence on the preoperative lung ultrasound, incidences of intra- and postoperative desaturation, and incidences of postoperative fever and postoperative pulmonary complications. RESULTS: Significant atelectasis incidence on the postoperative lung ultrasound was similar between the low and high FI O2 groups (28% vs 37%; Pearson chi-square value = 0.847; P = .357; OR 1.531; 95% CI 0.617-3.800). Significant atelectasis incidence on the preoperative lung ultrasound was also similar between the groups (12% vs 9%; Pearson chi-square value = 0.124; P = .725; OR 0.779; 95% CI 0.194-3.125). There were no statistically significant differences in the other secondary outcomes. CONCLUSIONS: FI O2 did not affect significant atelectasis formation in mechanically ventilated children who received ultrasound-guided recruitment maneuver and positive end-expiratory pressure.

Accuracy of pulse oximeters at low oxygen saturations in children with congenital cyanotic heart disease: An observational study.

BACKGROUND: Pulse oximetry overestimates arterial oxygen saturation (SaO2 ) at less than 90% saturation in cyanotic children. The Masimo Blue sensor (Masimo Corp., Irvine, CA) is a pulse oximetry sensor developed for use in children with cyanosis. However, there remains a lack of research in actual clinical practice. AIMS: We evaluated the intraoperative performance of three different pulse oximeters to measure oxyhemoglobin saturation (SpO2 ) at low saturations in pediatric patients with cyanotic heart disease and the influence of clinical variables (SaO2 , hemoglobin concentration, perfusion index, and weight) on the accuracy of the sensors. METHODS: This prospective observational study compared SpO2 measured using three pulse oximeters (Masimo Blue [Masimo Corp., Irvine, CA]; Masimo LNCS, and Nellcor [Medtronic, Dublin, Ireland]) at selected SaO2 ranges (≥85%, 75%-84%, 60%-74%, and < 60%). Accuracy was evaluated according to bias and Bland-Altman analysis with appropriate correction for multiple measurements. Relationships between bias and clinical variables were assessed using a generalized estimating equation. RESULTS: Two hundred and fifty-eight samples were analyzed. The mean overall bias (limits of agreement) of Masimo Blue, Masimo LNCS, and Nellcor sensor was -5.3 (-20.9 to 10.3%), -7.4 (-21.9 to 7.1%), and -7.4 (-22.5 to 15.1%), respectively. However, there was no difference in bias among the three sensors at SaO2 <60%. Generalized estimating equation showed that SaO2 value was associated with bias of all sensors. Perfusion index affected the bias of Blue sensor and LNCS sensor, and patients' weight was associated with bias of Nellcor sensor. CONCLUSION: Masimo blue sensor demonstrated overall lower bias compared to the other two sensors. However, the accuracy of all sensors was similarly poor at SaO2 less than 60%. Bias was influenced by SaO2 , perfusion index, and body weight.

Effect of Institutional Kidney Transplantation Case-Volume on Post-Transplant Graft Failure: a Retrospective Cohort Study.

BACKGROUND: The impact of institutional case volume to graft failure rate after adult kidney transplantation is relatively unclear compared to other solid organ transplantations. METHODS: A retrospective cohort study of 13,872 adult kidney transplantations in Korea was performed. Institutions were divided into low- (< 24 cases/year), medium- (24-60 cases/year), and high- (> 60 cases/year) volume centers depending on the annual case volume. One-year graft failure rate was defined as the proportion of patients who required dialysis or re-transplantation at one year after transplantation. Postoperative in-hospital mortality and long-term graft survival were also measured. RESULTS: After adjustment, one year graft failure was higher in low-volume centers significantly (adjusted odds ratio [aOR], 1.50; 95% confidence interval [CI], 1.26-1.78; P < 0.001) and medium-volume centers (aOR, 1.87; 95% CI, 1.57-2.23; P < 0.001) compared to high-volume centers. Low-volume centers had significantly higher mortality (aOR, 1.75; 95% CI, 1.15-2.66; P = 0.01) than that of high-volume centers after adjustment. Long-term graft survival of up to 9 years was superior in high-volume centers compared to low- and medium-volume centers (P < 0.001). CONCLUSION: Higher-case volume centers were associated with lower one-year graft failure rate, lower in-hospital mortality, and higher long-term graft survival after kidney transplantation.