Efficacy of Erector Spinae Plane Block for Analgesia in Thoracic Surgery: A Systematic Review and Meta-Analysis

OBJECTIVE

The objective of this study was to determine whether erector spinae plane block (ESPB) can provide an effective analgesia for managing pain after thoracic surgery and compare the efficacy of ESPB with that of other regional analgesic techniques.

DESIGN

Systematic review and meta-analysis of randomized controlled trials.

SETTING

PubMed, EMBASE, CENTRAL, CINAHL, Scopus, and Web of Science were searched.

PARTICIPANTS

Patients undergoing thoracic surgeries.

INTERVENTION

Erector spinae plane block with local anesthetics for postoperative analgesia.

MEASUREMENT AND MAIN RESULTS

Seventeen studies, including 1,092 patients, were included in the final analysis. Erector spinae plane block reduced 24-hour postoperative opioid consumption (mean difference [MD] -17.49, 95% CI -26.87 to -8.12), pain score at rest (MD -0.82, 95% CI -1.31 to -0.33), and pain score at movement (MD -0.77, 95% CI -1.20 to -0.3) compared to no block. Compared with other regional blocks, various results have been observed. Although statistical results showed that ESPB is inferior to thoracic paravertebral block and intercostal nerve block and superior to serratus anterior plan block in postoperative analgesia, clinical differences remain unclear. The incidence of hematoma was lower in the ESPB group than in the other groups (odds ratio 0.19, 95% CI 0.05-0.73).

CONCLUSION

Erector spinae plane block may provide effective analgesia after thoracic surgery. Compared with other techniques, it is a safer method, without clinically important differences, for postoperative pain control. Therefore, ESPB may be considered as a valuable option for postoperative pain management after thoracic surgery.

The influence of moderate or deep neuromuscular block status on anesthetic depth monitoring system during total intravenous anesthesia using propofol and remifentanil: A randomized trial

The neuromuscular block state may affect the electroencephalogram-derived index representing the anesthetic depth. We applied an Anesthetic Depth Monitoring for Sedation (ADMS) to patients undergoing laparoscopic cholecystectomy under total intravenous anesthesia, and evaluated the requirement of propofol according to the different neuromuscular block state. Adult patients scheduled to undergo laparoscopic cholecystectomy were enrolled and randomly assigned to either the moderate (MB) or deep neuromuscular block (DB) group. The UniCon sensor of ADMS was applied to monitor anesthetic depth and the unicon value was maintained between 40 and 50 during the operation. According to the group assignment, intraoperative rocuronium was administered to maintain proper neuromuscular block state, moderate or deep block state. The unicon value, electromyography (EMG) index, and total dose of propofol and rocuronium were analyzed. At similar anesthetic depth, less propofol was used in the DB group compared to the MB group (6.19 ± 1.36 in the MB mg/kg/h group vs 4.93 ± 3.02 mg/kg/h in the DM group, p = 0.042). As expected, more rocuronium were used in the DB group than in the MB group (0.8 ± 0.2 mg/kg in the MB group vs 1.2 ± 0.2 mg/kg in the DB group, p = 0.023) and the EMG indices were lower in the DB group than in the MB group, at several time points as follows: at starting operation (p < 0.001); at 15 (p = 0.019), 45 (p = 0.011), and 60 min (p < 0.001) after the initiation of the operation; at the end of operation (p = 0.003); and at 5 min after the administration of sugammadex (p < 0.001). At similar anesthetic depth, patients under the deep neuromuscular block state required less propofol with lower intraoperative EMG indices compared to those under the moderate neuromuscular block state during general anesthesia.

Role of Unfolded Protein Response and Endoplasmic Reticulum-Associated Degradation by Repeated Exposure to Inhalation Anesthetics in Caenorhabditis elegans

Background: When an imbalance occurs between the demand and capacity for protein folding, unfolded proteins accumulate in the endoplasmic reticulum (ER) lumen and activate the unfolded protein response (UPR). In addition, unfolded proteins are cleared from the ER lumen for ubiquitination and subsequent cytosolic proteasomal degradation, which is termed as the ER-associated degradation (ERAD) pathway. This study focused on changes in the UPR and ERAD pathways induced by the repeated inhalation anesthetic exposure in Caenorhabditis elegans. Methods: Depending on repeated isoflurane exposure, C. elegans was classified into the control or isoflurane group. To evaluate the expression of a specific gene, RNA was extracted from adult worms in each group and real-time polymerase chain reaction was performed. Ubiquitinated protein levels were measured using western blotting, and behavioral changes were evaluated by chemotaxis assay using various mutant strains. Results: Isoflurane upregulated the expression of ire-1 and pek-1 whereas the expression of atf-6 was unaffected. The expression of both sel-1 and sel-11 was decreased by isoflurane exposure, possibly indicating the inhibition of retro-translocation. The expression of cdc-48.1 and cdc-48.2 was decreased and higher ubiquitinated protein levels were observed in the isoflurane group than in the control, suggesting that deubiquitination and degradation of misfolded proteins were interrupted. The chemotaxis indices of ire-1, pek-1, sel-1, and sel-11 mutants decreased significantly compared to N2, and they were not suppressed further even after the repeated isoflurane exposure. Conclusion: Repeated isoflurane exposure caused significant ER stress in C. elegans. Following the increase in UPR, the ERAD pathway was disrupted by repeated isoflurane exposure and ubiquitinated proteins was accumulated subsequently. UPR and ERAD pathways are potential modifiable neuroprotection targets against anesthesia-induced neurotoxicity.

Effects of tranexamic acid on the activity of glutamate transporter EAAT3

Background

Tranexamic acid (TXA) is the most widely used hemostatic agent in surgical patients. However, when used in a high dose, it could cause a seizure in the postoperative period. The exact effector mechanism behind the seizure triggering remains unknown. Therefore, the authors investigated the effects of TXA on the activity of glutamate transporter type 3 (excitatory amino acid transporter 3; EAAT3), which is the main neuronal glutamate transporter type.

Methods

EAAT3 was expressed in Xenopus laevis oocytes through mRNA injection. Oocytes were incubated with diluted tranexamic acid for 72 h. Two-electrode voltage clamping was used to measure membrane currents before, during, and after applying 30 µM L-glutamate. Responses were quantified by integrating the current traces and reported in microcoulombs (µC). Results were presented as mean ± SEM.

Results

TXA (30 to 1,000 µM) significantly decreased EAAT3 activity. Our kinetic study showed that V_max was significantly decreased in the TXA group compared with the control group (1.1 ± 0.1 vs. 1.4 ± 0.1 µC, n = 18–23, P = 0.043), but the K_m did not significantly change (12.7 ± 3.9 µM for TXA vs. 12.8 ± 3.8 for control, n = 18–23, P = 0.986).

Conclusions

Our results suggest that TXA attenuates EAAT3 activity, which may explain its proconvulsant effect.

Retrospective Comparison between the Effects of Propofol and Inhalation Anesthetics on Postoperative Recurrence of Early- and Intermediate-Stage Hepatocellular Carcinoma

OBJECTIVE

Previous studies have reported that propofol has antitumor, anti-inflammatory, and antioxidant effects in addition to its anesthetic properties. To confirm this, a retrospective investigation was conducted to determine whether different anesthetic agents, particularly propofol and inhalation anesthetics, have an effect on the recurrence of hepatocellular carcinoma (HCC) in patients who were diagnosed with primary HCC and underwent laparoscopic hepatectomy.

SUBJECTS AND METHODS

Patients with Barcelona Clinic Liver Cancer stages 0, A, and B HCC, who underwent laparoscopic hepatic resection, were enrolled in this study. Post-operative HCC recurrence, which was determined from postoperative liver CT, was evaluated 24 months postoperatively with respect to the main anesthetic agents. The characteristics of HCC and other patient-related or surgery-related variables were evaluated together.

RESULTS AND CONCLUSION

During the 24-month period after hepatic resection, less HCC patients in the propofol group than in the inhalation group recurred (p = 0.046). The mean time to recurrence was 20.8 months (95% CI, 19.7-22.0) and 19.1 months (95% CI, 17.8-20.4) in the propofol group and the inhalation group, respectively. In addition, multivariable Cox proportional regression analysis revealed that the propofol group showed significantly decreased recurrence versus the inhalation group (hazard ratio, 0.57; 95% CI, 0.47-0.69; p = 0.029). When propofol was used as the main general anesthetic agent for laparoscopic hepatic resection, the postoperative 2-year recurrence rate decreased in early- and intermediate-stage HCC.

Association of Preoperative Serum Chloride Levels With Mortality and Morbidity After Noncardiac Surgery: A Retrospective Cohort Study

BACKGROUND

Postoperative hyperchloremia is known to be related to increases in mortality and morbidity after surgery. However, the relationship between preoperative hyperchloremia and hypochloremia and postoperative mortality and morbidity is not well established. Our aim was to evaluate the relationship between preoperative hyperchloremia or hypochloremia, as assessed using preoperative serum chloride tests, and 90-day mortality and morbidity after noncardiac surgery.

METHODS

In this retrospective cohort study, we reviewed the medical records of patients >20 years of age who underwent noncardiac surgery between January 2010 and December 2016. Patients were categorized into one of the following groups on the basis of the results of serum chloride testing performed within 1 month before surgery: normochloremia, 97-110 mmol·L; hyperchloremia, >110 mmol·L; and hypochloremia, <97 mmol·L. The primary end point of this study was the difference in postoperative 90-day mortality among the preoperative serum chloride groups. The secondary end point was the difference in postoperative acute kidney injury incidence among the preoperative serum chloride groups.

RESULTS

A total of 106,505 patients were included in the final analysis (2147 were allocated to the preoperative hypochloremia group and 617 to the hyperchloremia group). Multivariable Cox regression analysis revealed significantly increased 90-day mortality in the hypochloremia (hazard ratio, 1.46; 95% CI, 1.16-1.84; P = .001) and hyperchloremia (hazard ratio, 1.76; 95% CI, 1.13-2.73; P = .013) groups when compared with the normochloremia group. In addition, multivariable logistic regression analysis revealed a 1.83-fold increased odds of acute kidney injury in the preoperative hypochloremia group when compared with the normochloremia group (odds ratio, 1.83; 95% CI, 1.53-2.19; P < .001).

CONCLUSIONS

Preoperative hypochloremia and hyperchloremia were related to increased 90-day mortality after noncardiac surgery. In addition, preoperative hypochloremia was related to an increased risk for postoperative acute kidney injury.

Comparison of Intraoperative Sedation With Dexmedetomidine Versus Propofol on Acute Postoperative Pain in Total Knee Arthroplasty Under Spinal Anesthesia: A Randomized Trial

BACKGROUND

In patients undergoing total knee arthroplasty under spinal anesthesia, we compared the postoperative analgesic effect of intraoperative sedation with dexmedetomidine versus propofol. We hypothesized that sedation with dexmedetomidine would result in lower postoperative opioid analgesic consumption than with propofol.

METHODS

Forty-eight patients were enrolled and randomly assigned to either a dexmedetomidine group (n = 24), which received a loading dose of 1 μg/kg dexmedetomidine over 10 minutes, followed by a continuous infusion of 0.1-0.5 μg·kg·hour, or a propofol group (n = 24), which received a continuous infusion of propofol via a target-controlled infusion to maintain the effect-site concentration within a range of 0.5-2.0 μg/mL. The drug infusion rate was determined according to the sedation level, targeting a modified observer's assessment of alertness/sedation score of 3 or 4. The cumulative amounts of fentanyl administered via intravenous patient-controlled analgesia were recorded at 24 and 48 hours postoperatively (primary outcome). The postoperative numerical rating scale for pain was assessed at 6, 12, 24, and 48 hours (secondary outcome). The postoperative use of additional rescue analgesic (ketoprofen) and antiemetic drugs was also compared between the 2 groups at 24 and 48 hours.

RESULTS

Dexmedetomidine significantly reduced postoperative fentanyl consumption (median [interquartile range]) during 0-24 hours (45 [30-71] vs 150 [49-248] μg, P = .004; median difference = -105 μg [99.98% CI, 210-7.5]), 24-48 hours (90 [45-143] vs 188 [75-266] μg, P = .005; median difference = -98 μg [99.98% CI, 195-45]), and 0-48 hours (135 [68-195] vs 360 [146-480] μg, P = .003; median difference = -225 μg [99.98% CI, 405-7.5]). The numerical rating scale (median [interquartile range]) was lower at 6 hours (1 [0-2] vs 2 [1-3], P = .003), 12 hours (1 [1-2] vs 3 [2-3], P < .001), 24 hours (1 [1-2] vs 3 [2-3], P < .001), and 48 hours (2 [2-3] vs 3 [3-4], P < .001) after surgery in the dexmedetomidine group compared to the propofol group. No significant intergroup differences were observed in the amount of rescue analgesics and antiemetics at 24 hours (P = .155 and P = .482) and 48 hours (P = .082 and P = .153) after surgery.

CONCLUSIONS

Intraoperative dexmedetomidine sedation was associated with a small but clinically important reduction in postoperative opioid use after total knee arthroplasty.

Intraoperative continuous noninvasive hemoglobin monitoring in patients with placenta previa undergoing cesarean section: a prospective observational study

Background

Obstetric patients with placenta previa are at risk for sever peripartum hemorrhage. Early detection of anemia and proper transfusion strategy are important for the management of obstetric hemorrhage. In this study, we assessed the utility and accuracy of noninvasive hemoglobin (SpHb) monitoring in patients with placenta previa during cesarean section.

Methods

Parturients diagnosed with placenta previa and scheduled for cesarean section under spinal anesthesia were enrolled. SpHb and laboratory Hb (Lab-Hb) were measured during surgery as primary outcomes.

Results

Seventy-four pairs of SpHb and Lab-Hb were collected from 39 patients. The correlation coefficient was 0.877 between SpHb and Lab-Hb (P < 0.001). The Bland–Altman plot showed a mean difference ± SD of 0.3 ± 0.8 g/dl between noninvasive Hb and Lab-Hb, and the limits of agreement were −1.2 to 1.8 g/dl. The magnitude of the difference between SpHb and Lab-Hb was < 0.5 g/dl in 64.9%; however, it was > 1.5 g/dl in 10.8%.

Conclusions

SpHb monitoring had a good correlation with Lab-Hb. A small mean difference between SpHb and lab-Hb might not be clinically significant; however, the limits of agreements were not narrow. In particular, SpHb could be overestimated in the anemic population. Based on our results, further studies investigating the accuracy and precision of SpHb monitoring should be performed in parturients presenting Hb below 10 g/dl.

Comparison of standard versus 90° rotation technique for LMA Flexible™ insertion: a randomized controlled trial

Background

Insertion of a flexible laryngeal mask airway (LMA Flexible) is known to be more difficult than that of a conventional laryngeal mask airway. The 90° rotation technique can improve the success rate with a conventional laryngeal mask airway but its effect with the LMA Flexible remains unknown. We assessed whether the 90° rotation technique increased the first-attempt success rate of LMA Flexible insertion versus the standard technique.

Methods

In total, 129 female patients undergoing breast surgery were analyzed. The primary endpoint was success at the first attempt. The insertion time, number of trials, number of manipulations required, and oropharyngeal leak pressure were also evaluated. Heart rate and mean blood pressure were recorded 1 min before and 1 min after insertion. Blood staining on the LMA Flexible after removal and postoperative sore throat were checked.

Results

The first-attempt success rates were comparable between the groups (93% vs. 98.3%, P = .20). The insertion time, number of trials and manipulations, hemodynamic variables, and complications, such as blood staining and sore throat, did not differ between the groups.

Conclusions

The 90° rotation technique is a good alternative to the standard technique for insertion of the LMA Flexible.

Trial registration

ClinicalTrials.gov (NCT03028896). It was registered retrospectively at Jan 19th, 2017.

The effect of neuromuscular reversal agent on postoperative pain after laparoscopic gastric cancer surgery: Comparison between the neostigmine and sugammadex

Use of sugammadex for neuromuscular block reversal is associated with fewer postoperative complications than neostigmine; however, the effects on postoperative pain outcomes are largely unknown. In this retrospective study, we investigated the relationship between neuromuscular reversal agents and postoperative pain-related outcomes following laparoscopic gastric cancer surgery.We reviewed the electronic health records of patients who underwent laparoscopic gastric cancer surgery between January 2010 and June 2017. Patients were divided into a sugammadex group and a neostigmine group, according to the neuromuscular block reversal agent used. We compared the pain outcomes in the first 3 days postoperatively (POD 0-3), length of hospital stay, and postoperative complications (Clavien-Dindo grade ≥II).During the study period, 3056 patients received sugammadex (n = 901) or neostigmine (n = 2155) for neuromuscular reversal. After propensity score matching, 1478 patients (739 in each group) were included in regression analysis. In linear regression analysis, intravenous morphine equivalent consumption (mg) during POD 0 to 3 was higher in the sugammadex group than in the neostigmine group [coefficient 103.41, 95% confidence interval (CI): 77.45-129.37; P <.001]. However, hospital stay was shorter (coefficient: -0.60, 95% CI -1.12 to -0.08; P = .025) and postoperative complication rate was lower (odds ratio: 0.20, 95% CI 0.07-0.58; P = .003) in the sugammadex group.In this retrospective study, patients undergoing laparoscopic gastric cancer surgery who received sugammadex for neuromuscular block reversal exhibited greater postoperative analgesic requirements than those who received neostigmine but had a shorter hospital stay and a lower postoperative complication rate. A randomized and blinded study should be conducted in the future to confirm the findings of the present study.

Perioperative sedative use is not associated with acute kidney injury after total hip or knee arthroplasty

Background

The use of sedatives (propofol or dexmedetomidine) is common in total knee arthroplasty (TKA) or total hip arthroplasty (THA) under spinal anesthesia. Although propofol and dexmedetomidine have been reported to decrease the risk of acute kidney injury (AKI) after cardiac surgery, their effects on AKI incidence after TKA or THA are still unknown. The purpose of this study was to investigate the associations between sedative dosage (propofol and dexmedetomidine) and AKI incidence after TKA or THA under spinal anesthesia.

Methods

This retrospective observational study analyzed medical records of adult patients aged 18 years or older who underwent unilateral TKA or THA under spinal anesthesia at a single tertiary care hospital between January 2007 and June 2018. Data were analyzed using univariable and multivariable logistic regression analyses.

Results

A total of 5,663 patients were included in the analysis (TKA: 3,570, 63.0%; THA: 2,093, 37.0%), and 147 patients (2.6%) developed AKI in postoperative days 0-3. Multivariable logistic regression analysis showed that propofol dosage (odds ratio: 0.99, 95% confidence interval: 0.94, 1.05; P=0.839) and dexmedetomidine dosage (odds ratio: 0.95, 95% confidence interval: 0.84, 1.09; P=0.461) were not significantly associated with AKI incidence.

Conclusions

This study demonstrated no significant association between sedative uses (propofol, dexmedetomidine) and AKI incidence after THA or TKA under spinal anesthesia, and use of such sedatives does not require extreme caution.

A Comparison of Hemostatic Properties between Monopolar and Bipolar Hysteroscopic Surgery using Rotational Thromboelastometry: A Randomized Trial

OBJECTIVE

Systemic absorption of irrigation fluid can lead to a disturbed coagulation cascade. We compared the changes in hemostatic properties on using nonelectrolyte solution in monopolar hysteroscopic surgery (HS) with that on using isotonic saline in bipolar HS via rotational thromboelastometry (ROTEM) analysis.

METHODS

A total of 54 patients were randomized into 2 groups: 1 group underwent monopolar HS using a mixture of 2.7% sorbitol and 0.54% mannitol (the HSMP group), whereas the other group underwent bipolar HS using 0.9% isotonic saline (the HSBP group). The effects of these 2 methods on coagulation were assessed via pre and postoperative laboratory tests, including estimation of the international normalized ratio of prothrombin time and activated partial thromboplastin time and ROTEM analysis. In addition, the hemoglobin, hematocrit, and electrolyte levels and the platelet count were analyzed.

RESULTS

Patient characteristics, volume of irrigation fluid absorbed, and type of procedure were comparable between the 2 groups. There were no significant differences in the pre and postoperative values of ROTEM parameters between the 2 groups. Most postoperative ROTEM parameters, as compared with preoperative values, changed in both groups; clot formation time was prolonged, and the α-angle and maximum clot firmness were decreased. All ROTEM parameters were maintained within the normal range. Hematological parameters, including hemoglobin and hematocrit levels and platelet count, were significantly decreased postoperatively in both groups compared to the preoperative values. No pre and postoperative hematological and hemostatic parameters were significantly different between the 2 groups.

CONCLUSION

Irrigation fluid absorbed in healthy women during HS caused hypocoagulable changes in the blood, irrespective of the irrigant type, and no significant differences between HS using monopolar and bipolar electrodes were demonstrated.

The effect of repeated isoflurane exposure on serine synthesis pathway during the developmental period in Caenorhabditis elegans

BACKGROUND

Serine synthetic pathway plays an essential role in the development and function of the nervous system. This study investigated whether the serine synthetic pathway was affected by repeated volatile anesthetic exposure using C. elegans and its relationship with anesthesia-induced neurotoxicity.

METHODS

Synchronized worms were divided into two groups: the control and isoflurane groups. Worms in the isoflurane group were exposed to isoflurane for 1 h at each larval stage. The chemotaxis index was evaluated when they reached the young adult-stage in both groups. Also, RNA was extracted from the young adult-worms, and the expressions of C31C9.2, F26H9.5, and Y62E10 A.13 were evaluated using real-time polymerase chain reaction in both groups. At the same time, the l-serine level was measured. After phosphoserine phosphatase inhibitor - glycerophosphorylcholine (GPC) - and l-serine were treated, the change of chemotaxis index was determined.

RESULTS

In young adult worms exposed to isoflurane, the genetic expressions of C31C9.2, F26H9.5, and Y62E10 A.13 were decreased, and a significant decrease was shown in Y62E10 A.13. The serine level in worms was also lower in the isoflurane group than in the control group (5.13 ± 1.44 vs. 7.65 ± 0.81 pM, n = 5 in each group, p = 0.009). Exposure to GPC reduced the chemotaxis index to a similar degree as repeated isoflurane exposure (52.9% in GPC group vs 58.7% in the isoflurane group). The chemotaxis index (61.1%) was not decreased by repeated isoflurane anesthesia in GPC-treated worms. In this condition, the l-serine level was low similarly in both groups (5.22 ± 1.19 vs. 4.90 ± 1.36 pM, n = 5 in each group, p = 0.702). When l-serine was supplied to C. elegans, the deteriorated chemotaxis index by isoflurane exposure recovered (78.1% in the control group vs. 75.5% in the isoflurane group, p = 0.465).

CONCLUSION

Serine synthetic pathway was negatively affected in C. elegans by repeated isoflurane exposure. Y62E10 A.13, which corresponds to phosphoserine phosphatase, was mostly influenced, followed by low l-serine level. Supplementation with l-serine could restore the chemotaxis index.

Value of preoperative spirometry test in predicting postoperative pulmonary complications in high-risk patients after laparoscopic abdominal surgery

Whether preoperative spirometry in non-thoracic surgery can predict postoperative pulmonary complications (PPCs) is controversial. We investigated whether preoperative spirometry results can predict the occurrence of PPCs in patients who had undergone laparoscopic abdominal surgery. This retrospective observational study analyzed the records of patients who underwent inpatient laparoscopic gastric or colorectal cancer surgery at Seoul National University Bundang Hospital between January 2010 and June 2017. Preoperative spirometry was performed for patients at a high risk of PPCs, such as elderly patients (age >60 years), patients aged <60 years with chronic pulmonary disease, and current smokers. The main outcome was the association between the results of spirometry tests performed within 1 month prior to surgery and the occurrence of PPCs, as determined by multivariable logistic regression analysis. Of the 898 included patients who underwent laparoscopic gastric (372 patients) or colorectal cancer surgery (526 patients), PPC occurred in 117 patients (gastric cancer: 74, colorectal cancer: 43). A 1% greater preoperative forced vital capacity (FVC) was associated with a 2% lower incidence of PPCs after laparoscopic gastric or colorectal cancer surgery (odds ratio: 0.98, 95% confidence interval: 0.97–0.99, P = 0.018). However, the preoperative forced expiratory volume in 1 second (FEV1) (%) and FEV1/FVC (%) were not significantly associated with PPCs (P = 0.059 and P = 0.147, respectively). In conclusion, lower preoperative spirometry FVC, but not FEV1 or FEV1/FVC, may predict PPCs in high-risk patients undergoing laparoscopic abdominal surgery.

The effect of a mixture of 2.7% sorbitol-0.54% mannitol solution on blood coagulation: an invitro, observational healthyvolunteer study using rotational thromboelastometry (ROTEM)

Background

We investigated the effect of irrigation fluid on coagulation according to the hemodilution level using rotational thromboelastometry (ROTEM).

Methods

Venous blood was taken from 12 healthy volunteers and divided into four specimen tubes that were diluted to various levels (0%, 10%, 20%, and 40%) using an irrigation fluid composed of 2.7% sorbitol and 0.54% mannitol.

Results

Significant prolongation of clotting time was observed in the 40% diluted sample using both INTEM (P = 0.009) and EXTEM (P = 0.001) assays. However, the clot formation time was prolonged significantly in the 10%, 20%, and 40% diluted samples using both INTEM (P < 0.001) and EXTEM (P = 0.002, P < 0.001, and P < 0.001, respectively) assays. A significant decrease of α-angle of INTEM and EXTEM were observed in the 10% (P < 0.001), 20% (P < 0.001 and P = 0.001, respectively), and 40% (P < 0.001) groups compared with the 0% dilution group. The maximum clot firmness (MCF) of INTEM decreased significantly in the 20% (P < 0.001) and 40% (P < 0.001) diluted samples. In the MCF of EXTEM and FIBTEM assays, 10% (P = 0.009 and P = 0.015, respectively), 20% (P = 0.001), and 40% (P < 0.001) samples showed a significant decrease compared with the 0% sample. Nevertheless, most of the ROTEM values were within the reference range, except the 40% sample.

Conclusions

Blood became hypocoagulable when it was diluted in vitro with a fluid composed of 2.7% sorbitol and 0.54% mannitol.

Comparison of upper airway patency in patients with mild obstructive sleep apnea during dexmedetomidine or propofol sedation: a prospective, randomized, controlled trial

Background

In addition to propofol, dexmedetomidine is a suitable alternative for intraoperative sedation in procedures requiring regional anesthesia. To date, however, little is known about the influences of each drug on upper airway patency. Accordingly, the authors investigated differences between dexmedetomidine and propofol sedation in the occurrence of upper airway obstruction and requirements for airway intervention in patients with mild obstructive sleep apnea.

Methods

Patients with an apnea/hypopnea index of 5–14/h according to Watch-PAT 200 analysis were enrolled in this study. Spinal anesthesia was routinely performed for surgery. Intraoperative sedation was initiated using either dexmedetomidine or propofol infusion at a level of modified observer’s assessment of alertness/sedation scale 3. The primary outcome was the proportion of patients exhibiting signs of upper airway obstruction. A sign of upper airway obstruction was defined as no detection of end-tidal carbon dioxide for at least 10 s despite respiratory efforts.

Results

A total of 50 patients were included in the final analysis (dexmedetomidine [n = 26]; propofol [n = 24]). During the intraoperative sedation period, there was a significantly lower proportion of patients exhibiting signs of upper airway obstruction in the dexmedetomidine group than in the propofol group (11.5% vs. 41.7%, P = 0.035). An artificial airway was inserted in 1 patients (3.8%) and 5 patient (20.8%) in the dexmedetomidine and propofol groups, respectively (P = 0.093).

Conclusion

Dexmedetomidine sedation was associated with a lower incidence of upper airway obstruction than propofol sedation in patients with mild obstructive sleep apnea.

Trial registration number

Clinical trials.gov (NCT02993718): Retrospectively registered.

FIBTEM as a predictor of intra- and postoperative blood loss in revision total hip arthroplasty: A prospective observational study

Revision total hip arthroplasty (THA) may cause intra- and postoperative massive bleeding. This prospective observational study evaluated if the maximum clot firmness of FIBTEM (MCFFIB) could act as a predictor of perioperative massive bleeding in revision THA.Fifty-eight adult patients undergoing revision THA were included. Pre- and postoperative MCFFIB, hematological and hemostatic laboratory data, as well as the amount of intra- and postoperative blood loss (IBL and PBL) were obtained.The change rate (MCFFIB-C) between the pre- and postoperative MCFFIB had a significant correlation with IBL (ρ = 0.431, P = .001). Moreover, PBL had a significant correlation with MCFFIB-C (ρ = 0.292, P = .026). The MCFFIB-C cut-off value of ≥ 29% showed the highest sensitivity and specificity for predicting IBL ≥ 1000 mL or PBL ≥500 mL. The incidence of red blood cell transfusion in the postoperative period was higher in patients showing MCFFIB-C ≥ 29% (34% vs 8%, P = .015).The change rate between pre- and postoperative MCFFIB values was correlated well with the amount of IBL or PBL. Moreover, particular change rate of MCFFIB could predict massive bleeding in revision THA.

Intraoperative Nefopam Reduces Acute Postoperative Pain after Laparoscopic Gastrectomy: a Prospective, Randomized Study

BACKGROUND

We assessed whether intraoperative nefopam would reduce opioid consumption and relieve postoperative pain in patients undergoing laparoscopic gastrectomy.

METHODS

The 60 enrolled patients were randomly assigned to the control (n = 32) or nefopam (n = 28) group. All patients were blinded to their group assignment. We administered 100 ml of normal saline only (control group) or 20 mg of nefopam mixed in 100 ml normal saline (nefopam group) after anesthesia induction and at the end of surgery. The cumulative amount of fentanyl via intravenous patient-controlled analgesia (PCA), incidence of rescue analgesic medication, and numerical rating scale (NRS) for postoperative pain were evaluated along with the total remifentanil consumption.

RESULTS

The mean infusion rate of remifentanil was significantly lower in the nefopam group (0.08 ± 0.05 μg/kg/min) than in the control group (0.13 ± 0.06 μg/kg/min) (P < 0.001). Patients in the nefopam group required less fentanyl via intravenous PCA than those in the control group during the first 6 h after surgery (323.8 ± 119.3 μg vs. 421.2 ± 151.6 μg, P = 0.009). Additionally, fewer patients in the nefopam group than in the control group received a rescue analgesic during the initial 6 h postoperatively (78.6 vs. 96.9%, P = 0.028). The NRS measured while patients were in the post-anesthetic care unit was significantly lower in the nefopam group than in the control group (3.8 ± 1.1 vs. 4.8 ± 1.4, P = 0.012). The subsequent NRS obtained after patients had been transferred to the general ward was comparable between the two groups during the following postoperative period.

CONCLUSIONS

Intraoperative nefopam decreased postoperative pain and opioid consumption in the acute postoperative period after laparoscopic gastrectomy. Hence, nefopam may be considered as a component of multimodal analgesia after laparoscopic gastrectomy.

Comparison of intraoperative basal fluid requirements in distal pancreatectomy: Laparotomy vs. laparoscopy: A retrospective cohort study

There has been recent progress in intraoperative fluid therapy. However, little is known about intraoperative fluid therapy in laparoscopic surgery. The purpose of this study is to determine whether there are differences in the basal fluid requirements during surgery between laparotomy and laparoscopic distal pancreatectomy.This retrospective cohort study analyzed the electronic medical records of 253 patients who underwent distal pancreatectomy via either laparotomy (73 patients) or laparoscopy (180 patients) between June 2006 and March 2016. The volume of intraoperative fluid administered, postoperative complications, length of hospital stay, and readmission rate were evaluated. The total volume of fluids was calculated as the sum of the volume of crystalloid plus the volume of colloid multiplied by 1.5 or 2.0.Patients who had laparotomy were older and had higher American Society of Anesthesiologists classes. Anesthesia time was longer and estimated blood loss was larger in laparotomy. More colloid (1.8 mL/kg per h vs. 1.2 mL/kg per h, P < .001) and more total calculated fluid (1.5 times: 11.7 mL/kg per h vs. 10.6 mL/kg per h, P = .002; 2.0 times: 12.6 mL/kg per h vs. 11.2 mL/kg per h, P = .001) were infused in laparotomy. Crystalloid (9.0 mL/kg per h vs. 8.9 mL/kg per h, P = .203) did not show significant difference. Postoperative complications were more frequent (63% vs. 45%, P = .008), the hospital stay was longer (18 days vs. 13.4 days, P < .001), and readmission rate was higher (15% vs. 5.6%, P = .02) in laparotomy. By logistic regression analysis, we could find that operation type (laparotomy vs. laparoscopy, odds ratio 1.900, 95% confidence interval 1.072-3.368) and operation time (P = .004) had effect on complications.In patients undergoing distal pancreatectomy, basal fluid requirements were larger in laparotomy compared with laparoscopy. Operation time and estimated blood loss had effects on fluid administration. Postoperative complications were more frequent in laparotomy but we could not find relationships with infused colloid or total calculated fluid volumes. Operation type (laparotomy vs. laparoscopy) and operation time were the only related factors to postoperative complications.

Is neuromuscular blocker needed in children undergoing inguinal herniorrhaphy?: A prospective, randomized, and controlled trial

BACKGROUND

Intraoperative neuromuscular blocker is widely used, but is known to be associated with postoperative residual paralysis, which is known to be associated with increased risk of pulmonary complications. Hence, its use should be individualized and restricted to procedures where it is mandatory. We examined whether not using a neuromuscular blocker affects the surgical conditions in children undergoing inguinal herniorrhaphy.

METHODS

Anesthesia was induced and maintained with sevoflurane in 60% nitrous oxide, and the airway was maintained using an I-gel. In total, 66 children aged 1 to 6 years were randomized to receive rocuronium (rocuronium group, n = 33) or saline (control group, n = 33); 61 children of them finished the study. A single surgeon who performed the operation rated the surgical condition of each patient on a 4-point scale (1 = poor, 2 = acceptable, 3 = good, and 4 = excellent). Intraoperative patient movement, recovery time, emergence agitation, and postoperative pain scores were evaluated.

RESULTS

One patient in control group and no patient in rocuronium group showed intraoperative movement. When noninferiority test was done for intraoperative patient movement, with the noninferiority margin of 20%, the difference of absolute risk was 3.3% (95% confidence interval -8.0% to 16.7%) and saline group was noninferior to rocuronium group. All of the patients showed good to excellent surgical conditions, and no difference was found between the 2 groups. The recovery time was shorter in the control group than in the rocuronium group (4.5 ± 1.8 vs 5.6 ± 2.2 minutes, respectively; P = .028).

CONCLUSION

In children aged 1 to 6 years undergoing inguinal herniorhaphy under sevoflurane anesthesia using an I-gel, not using neuromuscular blocker showed similar intraoperative condition and shortened recovery time compared with using neuromouscular blocker.

Intraoperative dexmedetomidine sedation reduces the postoperative agitated behavior in elderly patients undergoing orthopedic surgery compared to the propofol sedation

BACKGROUND

Postoperative agitation or confusion is one of the symptoms of hyperactive delirium in elderly patients. We retrospectively evaluated the incidence of postoperative abnormal psychomotor behavior in elderly surgical patients according to the use of different intraoperative sedative agents: dexmedetomidine vs. propofol.

METHODS

The medical records of 855 elderly patients, who underwent orthopedic surgery with regional anesthesia between July 2012 and September 2015, were divided into two groups, the dexmedetomidine group (N.=263) and the propofol group (N.=592), and then evaluated. Agitated behavior was evaluated as the primary outcome, and patient-, surgery-, and anesthesia-related factors, as well as other postoperative complications, were investigated as secondary outcomes. To reduce the risk of confounder effects between the two groups, 263 patients were selected from the propofol group by propensity score matching.

RESULTS

In the propensity-score-matched groups, the incidence of agitated behavior was lower in the dexmedetomidine group compared with the propofol group (6 [2.3%] vs. 17 [6.5%], P=0.027). All pre- and postoperative laboratory values were comparable between the two groups, including hemoglobin, hematocrit, platelet count, C-reactive protein, electrolytes, creatinine, glomerular filtration rate, and albumin. Moreover, intraoperative propofol sedation, older age, higher Charlson comorbidity index, and hip surgery were found to be significant factors for the occurrence of agitation.

CONCLUSIONS

This study suggests that intraoperative dexmedetomidine sedation, as compared with propofol sedation, may have a greater beneficial effect in reducing agitated behavior in elderly patients undergoing orthopedic surgery with regional anesthesia.

A Study on CYP2C19 and CYP2D6 Polymorphic Effects on Pharmacokinetics and Pharmacodynamics of Amitriptyline in Healthy Koreans

We performed a double-blinded, genotype-based stratification study to explore the pharmacokinetics and pharmacodynamics of amitriptyline according to CYP2C19 and CYP2D6 genotype in Korean subjects. Twenty-four healthy adults were grouped by genotype of CYP2C19 and CYP2D6. After a single dose of 25 mg of amitriptyline, blood samples were collected and anticholinergic effects were measured. The extent of N-demethylation of amitriptyline significantly decreased in subjects carrying two nonfunctional alleles of CYP2C19. The extent of hydroxylation of amitriptyline or nortriptyline was significantly reduced in subjects carrying two CYP2D6 decreased functional alleles compared with those with no or one decreased functional allele. The overall metabolic pathway of amitriptyline was more likely to be dominated by CYP2C19 than CYP2D6. The gene variations of CYP2C19 and CYP2D6 did not change the pharmacodynamic effect. The findings of this study will provide useful information on individualized drug treatment with amitriptyline considering both CYP2D6 and CYP2C19 gene variations.

The impact of irrigating fluid absorption on blood coagulation in patients undergoing transurethral resection of the prostate: A prospective observational study using rotational thromboelastometry

Although endoscopic transurethral resection of the prostate (TURP) is a well-established procedure as a treatment for benign prostatic hyperplasia, its complications remain a concern. Among these, coagulopathy may be caused by the absorption of irrigating fluid. This study aimed to evaluate such phenomenon using a rotational thromboelastometry (ROTEM).A total of 20 patients undergoing TURP participated in this study. A mixture of 2.7% sorbitol-0.54% mannitol solution and 1% ethanol was used as an irrigating fluid, and fluid absorption was measured via the ethanol concentration in expired breath. The effects on coagulation were assessed by pre- and postoperative laboratory blood tests, including hemoglobin, hematocrit, platelet count, international normalized ratio of prothrombin time (PT-INR), activated partial thromboplastin time, electrolyte, and ROTEM.INTEM-clotting time (INTEM-CT) was significantly lengthened by 14% (P = 0.001). INTEM-α-angle was significantly decreased by 3% (P = 0.011). EXTEM-clot formation time was significantly prolonged by 18% (P = 0.008), and EXTEM-maximum clot firmness (EXTEM-MCF) was significantly decreased by 4% (P = 0.010). FIBTEM-MCF was also significantly decreased by 13% (P = 0.015). Moreover, hemoglobin (P < 0.001), hematocrit (P < 0.001), platelet counts (P < 0.001), potassium (P = 0.024), and ionized calcium (P = 0.004) were significantly decreased, while PT-INR (P = 0.001) was significantly increased after surgery. The amount of irrigating fluid absorbed was significantly associated with the weight of resected prostatic tissue (P = 0.001) and change of INTEM-CT (P < 0.001).As shown by the ROTEM analysis, the irrigating fluid absorbed during TURP impaired the blood coagulation cascade by creating a disruption in the coagulation factor activity or by lowering the coagulation factor concentration via dilution.

A prospective, randomized and controlled study of interscalene brachial plexus block for arthroscopic shoulder surgery: A comparison of C5 and conventional approach, a CONSORT-compliant article

BACKGROUND

The shoulder area is mainly innervated with the C5 and C6 nerve roots, and interscalene brachial plexus block (ISB) is widely used for postoperative analgesia after shoulder surgery. However, it is associated with adverse effects, such as numbness and weakness in the blocked arm due to an unwanted block of the lower brachial plexus (C7-T1). We hypothesized that the C5 approach during ISB would provide postoperative analgesia while minimizing adverse events after arthroscopic shoulder surgery.

METHODS

A total of 92 patients scheduled for arthroscopic shoulder surgery were enrolled and randomly assigned to 1 of the 3 groups: The control (no ISB, n = 31), conventional ISB (ISB with the conventional approach, n = 31), or C5 ISB (ISB with the C5 approach, n = 30) group. ISB was performed before the induction of anesthesia, and a subacromial catheter was placed in all patients at the end of the surgery. Postoperative pain scores, numbness, and weakness were recorded at 2, 8, and 24 hours after surgery. Oxygen saturation and overall patient satisfaction scores were also assessed at 1 and 48 hour after surgery, respectively.

RESULTS

The pain scores were lower in the conventional ISB group and the C5 ISB group than in the control group at postoperative 2 and 8 hours (P < 0.05). The incidence and degree of numbness and weakness of the blocked arm were significantly lower in the C5 ISB group than in the conventional ISB group (P < 0.05). Oxygen saturation were lower in the conventional ISB group and C5 ISB group than in the control group (P = 0.01). Overall patient satisfaction scores were higher in the C5 ISB group than in the control or conventional ISB group (P < 0.01).

CONCLUSION

The C5 approach for ISB provides analgesia as effectively as the conventional approach following arthroscopic shoulder surgery, with the advantages of minimal numbness and weakness.