The utility of the perfusion index as an indicator of anesthetic depth for repeated propofol sedation in children: An observational study.

BACKGROUND: Children receiving proton therapy require repeated sedation. In this study, we aimed to investigate the utility of the perfusion index (PI) for evaluating consciousness level during repeated propofol sedation. METHODS: In this prospective observational study, children aged from birth to 19 years old scheduled for proton therapy under repeated propofol sedation were enrolled. The primary outcome was the equivalence of PI values 5 min after anesthesia induction on consecutive sedation. Total consumption of propofol during sedation, time to reach the University of Michigan sedation scale (UMSS) score 1 after end of proton therapy, and duration of post-anesthesia care unit (PACU) stay were recorded. RESULTS: The PI values measured 5 min after induction of anesthesia were not equivalent to each other in consecutive sedation except for the second versus third (1st vs. 2nd: 97.5% CI: -1.34, 0.91; p = 0.206, 0.034; 2nd vs. 3rd: 97.5% CI: -0.87, 0.94; p = 0.023, 0.036 3rd vs. 4th: 97.5% CI: -2.08, -0.26; p < 0.99, <0.001; 4th vs. 5th: 97.5% CI: 0.21, 2.28; p < 0.001, >0.99; respectively). In consecutive sedation, there was not a significantly different difference in the time to reach UMSS score 1 (p > 0.99, all) for total consumption of propofol, time to reach UMSS score 1 after the end of proton therapy, and duration of PACU stay. CONCLUSIONS: During repeated propofol sedation in children, PI was insufficient to be used as an indicator of consciousness level assessment. However, we suggest that the information related to repeated sedation provided by this study may be helpful in clinical practice.

Risk factors associated with hypotensive bradycardic events during open shoulder surgery in the beach chair position.

BACKGROUND: Shoulder surgery in the beach chair position frequently causes hypotensive bradycardic events (HBEs), which are potentially associated with an increased risk of cerebral hypoperfusion. Here, we aimed to investigate the incidence and characteristics of symptomatic HBEs that require pharmacological interventions, and to identify specific risk factors associated with symptomatic HBEs. METHODS: We retrospectively examined the records of all patients aged ≥ 18 years who underwent shoulder arthrotomy in the beach chair position between January 2011 and December 2018 at Samsung Medical Center. For patients who experienced HBEs while in the beach chair position, the minimum heart rate and systolic blood pressure were noted, as was the total dose of ephedrine or atropine. RESULTS: Symptomatic HBEs occurred in 61.0% of all cases (256/420). Two patients with symptomatic HBEs experienced postoperative neurological complications. Multivariable logistic regression analysis showed that preoperative interscalene brachial plexus block (ISB) and advanced age were risk factors associated with symptomatic HBEs (odds ratio [OR]: 3.240, 95% CI: 2.003, 5.242, P < 0.001; OR: 1.060 for each 1-year increase, 95% CI: 1.044, 1.076, P < 0.001, respectively). Receiver operating curve analysis revealed that a threshold of 62 years of age had a moderate degree of accuracy for predicting symptomatic HBEs (area under curve: 0.764, 95% CI: 0.720, 0.804, P < 0.001). CONCLUSIONS: Considering the increasing risk of neurocognitive complications with aging, proactive hemodynamic management is needed, especially for elderly patients undergoing shoulder surgery in the beach chair position using ISB.

Association between intraoperative hypotension and postoperative myocardial injury in patients with prior coronary stents undergoing high-risk surgery: a retrospective study.

PURPOSE: We conducted a single-center retrospective study to evaluate the effects of intraoperative hypotension (IOH) on postoperative myocardial injury during major noncardiac surgery in patients with prior coronary stents with preoperatively normal cardiac troponin I levels. Although IOH is assumed to increase the risk of postoperative myocardial injury in patients with prior coronary stents, the level and duration of hazardous low blood pressure have not been clarified. METHODS: Of 2517 patients with prior coronary stents undergoing noncardiac surgery between January 2010 and March 2017, we analyzed 195 undergoing major surgery (vascular, abdominal, and thoracic surgery) who had a normal preoperative high-sensitivity cardiac troponin I (hs-cTnI) level and were followed up postoperatively within 3 days. Postoperative myocardial injury was defined as a hs-cTnI level greater than the 99th percentile reference value. Primary IOH exposure was defined as a decrease of ≥ 50%, 40%, or 30% from the preinduction mean blood pressure. Additional definition of IOH was absolute mean blood pressure < 70, < 60 or < 50 mmHg. Multivariate logistic regression was used to model the exposure and myocardial injury. RESULTS: Myocardial injury occurred in 53 (27.2%) cases. The predefined levels of IOH were not significantly associated with postoperative myocardial injury, but intraoperative continuous inotropes/vasopressors use was significantly higher in patients with myocardial injury (P = 0.004). Operation time ≥ 166 min (OR = 2.823, 95% CI 1.184-6.731, P = 0.019) and abdominal vascular surgery (OR = 2.693, 95% CI 1.213-5.976, P = 0.015) were independent risk factors for myocardial injury. CONCLUSION: Although patients with prior coronary stents with normal hs-cTnI levels did not show association between varying levels of IOH and postoperative myocardial injury after noncardiac surgery, intraoperative need of continuous inotropes/vasopressors was higher in patients with postoperative myocardial injury. Abdominal vascular surgery and surgical time were independent risk factors for myocardial injury after surgery.

The effect of preventive use of corticosteroids on postoperative complications after esophagectomy: A retrospective cohort study.

Corticosteroids have been empirically administered to reduce the rate of acute respiratory distress syndrome (ARDS) after esophagectomy. However, their efficacy remains controversial, and corticosteroids may increase the risk of graft dehiscence and infection, which are major concerns after esophagectomy. Therefore, we compared the incidence of composite complications (ARDS, graft dehiscence and infection) after esophagectomy between patients who received a preventive administration of corticosteroids and those who did not. All patients who underwent esophagectomy from 2010 to 2015 at a tertiary care university hospital were reviewed retrospectively (n = 980). Patients were divided into Steroid (n = 120) and Control (n = 860) groups based on the preventive administration of 100 mg hydrocortisone during surgery. The primary endpoint was the incidence of composite complications. The incidence of composite complications was not different between the Control and Steroid groups (17.4% vs. 21.7% respectively; P = 0.26). The incidence rates of complications in each category were not different between the Control and Steroid groups: ARDS (3.8% vs. 5.0%; P = 0.46), graft dehiscence (4.8% vs. 6.7%; P = 0.37), and infection (12.8% vs. 15.8%; P = 0.36). Propensity score matching revealed that composite complications (20.0% vs. 21.7%; P = 0.75), ARDS (4.3% vs. 5.2%; P = 0.76) and infection (16.5% vs. 15.7%; P = 0.86) were not different between the Control and Steroid group, but the incidence of graft dehiscence was higher in the Steroid group than in the Control group (0.9% vs. 7.0%; P = 0.0175). In conclusions, the preventive use of corticosteroids did not reduce the incidence of ARDS, but may be related to an increased incidence of graft dehiscence. Therefore, routine administration of corticosteroids to prevent ARDS is not recommended in esophagectomy.

Sarcopenia as a predictor of post-transplant tumor recurrence after living donor liver transplantation for hepatocellular carcinoma beyond the Milan criteria.

To evaluate the association between sarcopenia and tumor recurrence after living donor liver transplantation (LDLT) in patients with advanced hepatocellular carcinoma (HCC), we analyzed 92 males who underwent LDLT for treating HCC beyond the Milan criteria. Sarcopenia was defined when the height-normalized psoas muscle thickness was <15.5 mm/m at the L3 vertebra level on computed tomography based on an optimum stratification method using the Gray's test statistic. Survival analysis was performed with death as a competing risk event. The primary outcome was post-transplant HCC recurrence. The median follow-up time was 36 months. There was a 9% increase in recurrence risk per unit decrease in height-normalized psoas muscle thickness. Twenty-six (36.1%) of 72 sarcopenic recipients developed HCC recurrence, whereas only one (5.0%) of 20 non-sarcopenic recipients developed HCC recurrence. Recurrence risk was greater in sarcopenic patients in univariable analysis (hazard ratio [HR] = 8.06 [1.06-16.70], p = 0.044) and in multivariable analysis (HR = 9.49 [1.18-76.32], p = 0.034). Greater alpha-fetoprotein and microvascular invasion were also identified as independent risk factors. Incorporation of sarcopenia improved the model fitness and prediction power of the estimation model. In conclusion, sarcopenia appears to be one of the important host factors modulating tumor recurrence risk after LDLT for advanced HCC.

The influence of patient position on withdrawal force of lumbar epidural catheters after total knee arthroplasty: A randomized trial.

STUDY OBJECTIVE: Elderly patients with degenerative knee disease may have accompanying degenerative spine conditions. There are no studies on lumbar epidural catheter withdrawal forces in these patients. The aim of this study was to investigate withdrawal forces and possible associated risk factors in patients undergoing total knee arthroplasty (TKA). DESIGN: Prospective randomized trial. SETTING: Operating room and ward in a university hospital. PATIENTS: Seventy-eight patients aged 65 to 80years who were undergoing TKA and combined spinal epidural anesthesia were enrolled. INTERVENTIONS: Lumbar epidural catheterization was performed in a lateral position before surgery and the patients were randomly allocated to one of 3 positions for removal: flexed lateral (L), prone (P), and sitting (S). On the third postoperative day, the lumbar epidural catheters were removed by a single investigator with the patient in the assigned position. MEASUREMENTS: We measured the peak tension during catheter withdrawal and evaluated the factors affecting peak tension. MAIN RESULTS: The forces required to remove the catheters were considerably greater in the sitting and prone than in the flexed lateral position: group P (3.9N [0.28-10.36]), group S (4.1N [0.04-11.57]), and group L (1.3N [0.07-3.65]) (P<.001). There was a positive correlation between the length of catheter in the epidural space and peak tension (P=.0026, ß coefficient=.223). CONCLUSIONS: For ease of removal of catheters from the lumbar epidural space, the flexed lateral position is recommended for elderly patients undergoing TKA. When placing the epidural catheter, the physician should be careful not to insert a catheter that is excessively long.

Association between Serum Bilirubin and Acute Intraoperative Hyperglycemia Induced by Prolonged Intermittent Hepatic Inflow Occlusion in Living Liver Donors.

BACKGROUND: Intermittent hepatic inflow occlusion (IHIO) is associated with acute hyperglycemia during living donor hepatectomy when the ischemia is prolonged. Bilirubin is a potent antioxidant to play an important role for maintaining insulin sensitivity and preventing hyperglycemia. Thus, we aimed to test whether serum bilirubin level is associated with prolonged IHIO-induced intraoperative hyperglycemia. METHODS: Seventy-five living liver donors who underwent a prolonged IHIO with a >30 minute cumulative ischemia were included. The association between preoperative serum bilirubin concentrations and the risk of intraoperative hyperglycemia (blood glucose concentration >180 mg/dl) was analyzed using binary logistic regression with adjusting for potential confounders including age and steatosis. RESULTS: The number of donors who underwent 3, 4, 5, and 6 rounds of IHIO was 41, 22, 7, and 5, respectively. Twenty-nine (35%) donors developed intraoperative hyperglycemia. Total bilirubin concentration was inversely associated with hyperglycemia risk (odds ratio [OR] 0.033, 95% confidence interval [CI] 0.004-0.313, P = 0.003). There was an interaction between age and total bilirubin concentration: the effect of lower serum total bilirubin (≤0.7 mg/dl) on the development of hyperglycemia was greater in older donors (>40 years) than in younger donors (P = 0.0.028 versus P = 0.212). Both conjugated bilirubin (OR 0.001 95% CI 0.001-0.684) and unconjugated bilirubin (OR 0.011 95% CI 0.001-0.246) showed an independent association with hyperglycemia risk. CONCLUSIONS: Lower preoperative serum bilirubin was associated with greater risk of prolonged IHIO-induced hyperglycemia during living donor hepatectomy particularly in older donors. Thus, more meticulous glycemic management is recommended when prolonged IHIO is necessary for surgical purposes in old living donors with lower serum bilirubin levels.

False Loss of Resistance in Cervical Epidural Injection: The Loss of Resistance Technique Compared with the Epidrum Guidance in Locating Epidural Space.

BACKGROUND: Epidural block failures can occur due to a misleading loss of resistance (LOR) signal. OBJECTIVE: This study was designed to evaluate the false LOR rate and to determine whether the Epidrum, which is an LOR device for identifying the epidural space, improves the ability to find the epidural space during cervical epidural injection compared the LOR technique. STUDY DESIGN: A randomized, single-blind trial. SETTING: Single academic medical center. METHODS: A total of 150 patients undergoing cervical interlaminar epidural injections at C7-T1 were randomized to receive either the LOR technique with a syringe (group C) or the Epidrum guidance (group E). Fluoroscopic images were used to confirm the accuracy of the needle placement within the epidural space. The rate of misleading epidural signals and adverse effects were recorded and analyzed. RESULTS: The false LOR rate was 74.7% for group C, 62.7% for group E, and 68.7% overall. The incidence of false LOR was not significantly different between the 2 groups. Also, the success rate and the rate of true epidural signals were similar between the 2 groups. LIMITATIONS: The Epidrum cannot be used to confirm whether the needle has entered the vascular space without fluoroscopy. CONCLUSIONS: In this study, we did not find any difference in accuracy between the Epidrum and the LOR technique with a syringe for detecting the cervical epidural space. The overall higher false LOR rate suggests that the combined use of fluoroscopy and LOR technique with a syringe or the Epidrum is necessary to increase the rate of finding the true cervical epidural space. CLINICAL TRIALS REGISTRATION: KCT0001333.

Anesthetic experience in a clinically euthyroid patient with hyperthyroxinemia and suspected impairment of T4 to T3 conversion: a case report.

We report an anesthetic experience in a clinically euthyroid patient with hyperthyroxinemia (elevated free thyroxine, fT4 and normal 3, 5, 3'-L-triiodothyronine, T3) and suspected impairment of conversion from T4 to T3. Despite marked hyperthyroxinemia, this patient's perioperative hemodynamic profile was suspected to be the result of hypothyroidism, in reference to the presence of T4 to T3 conversion disorder. We suspected that pretreatment with antithyroid medication before surgery, surgical stress and anesthesia may have contributed to the decreased T3 level after surgery. She was treated with liothyronine sodium (T3) after surgery which restored her hemodynamic profile to normal. Anesthesiologists may be aware of potential risk and caveats of inducing hypothyroidism in patients with euthyroid hyperthyroxinemia and T4 to T3 conversion impairment.

Fibrinogen recovery and changes in fibrin-based clot firmness after cryoprecipitate administration in patients undergoing aortic surgery involving deep hypothermic circulatory arrest.

BACKGROUND: Cryoprecipitate may be used to treat bleeding in cardiac surgery. Its effects on plasma fibrinogen and fibrin clotting in this setting are poorly defined. STUDY DESIGN AND METHODS: Patients undergoing on-pump aortic surgery with deep hypothermic circulatory arrest (DHCA) were recruited prospectively. After protamine reversal, cryoprecipitate was administered to patients with bleeding, and fibrin deficit was indicated by thromboelastometry (ROTEM)-based FIBTEM test. Coagulation was assessed using ROTEM-based tests and standard laboratory tests before and after cryoprecipitate. RESULTS: Thirteen patients were included. Cryoprecipitate significantly elevated EXTEM A10 from (mean ± standard deviation) 29.4 ± 5.8 to 34.8 ± 5.9 mm (p = 0.01), FIBTEM A10 from 3.5 ± 0.9 to 5.8 ± 1.7 mm (p = 0.04), and plasma fibrinogen concentration from 154.2 ± 25.6 to 193.4 ± 30.5 mg/dL (p = 0.01). EXTEM clot elasticity at 10 minutes (CE10) increased from 42.5 ± 12.0 to 54.7 ± 14.9 mm after cryoprecipitate (30.0% increase). FIBTEM CE10 increased from 3.7 ± 0.9 to 6.2 ± 2.0 mm (53.0% increase). A fibrinogen dose of 13.2 ± 5.2 mg/kg was required to increase FIBTEM A10 by 1 mm. In vivo recovery of fibrinogen was 61.6 ± 31.2%. CONCLUSIONS: Cryoprecipitate increased plasma fibrinogen levels and fibrin-based clotting in bleeding patients undergoing aortic surgery with DHCA. In vivo recovery of fibrinogen was considerably below 100% and fibrinogen content varied between cryoprecipitate units. Trials are needed to assess whether cryoprecipitate impacts clinical outcomes and to evaluate its safety.

Dynamic left ventricular outflow tract obstruction in living donor liver transplantation recipients -A report of two cases-.

We present two cases of dynamic left ventricular outflow tract obstruction in 2 patients who were undergoing living donor liver transplantation. On the preoperative transthoracic echocardiography, the first patient showed normal ventricular function and a normal wall thickness, but severe hemodynamic deterioration developed during the anhepatic period and this was further aggravated after reperfusion in spite of volume resuscitation and catecholamine therapy. Intraoperative transesophageal echocardiography revealed the systolic anterior motion of the mitral valve leaflet together with left ventricular outflow tract obstruction. The second patient showed left ventricular hypertrophy with left ventricular outflow tract obstruction on the preoperative echocardiography. Intraoperative transesophageal echocardiography was used to guide fluid administration and the hemodynamic management throughout the procedure and a temporary portocaval shunt was established to mitigate the venous pooling during the anhepatic period. The purpose of this report is to emphasize the clinical significance of dynamic left ventricular outflow tract obstruction in patients who are undergoing living donor liver transplantation and the role of intraoperative echocardiography to detect and manage it.

Risk factors of postoperative delirium following liver transplantation.

BACKGROUND: Postoperative delirium (POD) after liver transplantation is a serious complication. This study investigated the incidence and the risk factors of POD in liver transplantation recipients. METHODS: Three hundred and sixty eight adult recipients who had undergone liver transplantation were included. We reviewed medical records and the POD was determined by either psychiatric consultation or established diagnostic criteria. Recipients were divided into two groups according to the occurrence of POD: POD group (n = 150) and non-POD group (n = 218), and risk factors were assessed. RESULTS: One hundred fifty (40.8%) of the 368 recipients developed POD after liver transplantation. History of alcohol consumption and alcoholic liver disease, history of hepatic encephalopathy, preoperative mental status changes, ventilator care, dialysis, hypotension, and ICU care were significantly higher in the POD group. In the preoperative laboratory test, sodium was lower while bilirubin, PT (INR) and MELD score were higher in the POD group. Postoperative variables including dialysis, ventilator care duration, ICU stay, hospital stay, glucose and ammonia were significantly higher in the POD group. Three variables were identified as independent predictors of POD in a multiple regression analysis: history of alcohol consumption (odds ratio, 2.04; 95% confidence interval [CI], 1.12-3.72; P = 0.02), history of hepatic encephalopathy (odds ratio, 2.54; 95% CI, 1.46-4.41, P<0.01), and MELD score (odds ratio, 1.03; 95% CI, 1.00-1.06; P = 0.02). CONCLUSIONS: The development of POD and related morbidity and mortality would be reduced if we identified the recipients with risk factors preoperatively and applied early intervention.