Thromboelastographic evaluation after cardiac surgery optimizes transfusion requirements in the intensive care unit: a single-center retrospective cohort study using an inverse probability weighting method.

OBJECTIVE: There are no reports from Japan showing the effects of using the thromboelastography algorithm on transfusion requirements after Intensive Care Unit (ICU) admission, and post-implementation knowledge regarding the thromboelastography algorithm under the Japanese healthcare system is insufficient. Therefore, this study aimed to clarify the effect of the TEG6s thromboelastography algorithm on transfusion requirements for patients in the ICU after cardiac surgery. METHODS: We retrospectively compared the requirements for blood transfusion up to 24 h after ICU admission using the thromboelastography algorithm (January 2021 to April 2022) (thromboelastography group; n = 201) and specialist consultation with surgeons and anesthesiologists (January 2018 to December 2020) (non-thromboelastography group; n = 494). RESULTS: There were no significant between-group differences in terms of age, height, weight, body mass index, operative procedure, duration of surgery or cardiopulmonary bypass, body temperature, or urine volume during surgical intervention. Moreover, there was no significant between-group difference in the amount of drainage at 24 h after ICU admission. However, crystalloid and urine volumes were significantly higher in the thromboelastography group than in the non-thromboelastography group. Additionally, fresh-frozen plasma (FFP) transfusion volumes were significantly lower in the thromboelastography group. However, there were no significant between-group differences in red blood cell count or platelet transfusion volume. After variable adjustment, the amount of FFP used from the operating room to 24 h after ICU admission was significantly reduced in the thromboelastography group. CONCLUSIONS: The thromboelastography algorithm optimized transfusion requirements at 24 h after admission to the ICU following cardiac surgery.

＜Editors' Choice＞ Efficacy of pectoral nerve block type-2 (Pecs II block) versus serratus plane block for postoperative analgesia in breast cancer surgery: a retrospective study.

Thoracic wall nerve blocks reduce postoperative acute pain after breast cancer surgery (BCS); however, their short-term effects and the most effective technique remain unclear. To compare the effects of pectoral nerve block type-2 (Pecs II block) and serratus plane block for postoperative short-term analgesia, we retrospectively reviewed 43 BCS patients who underwent Pecs II block (n=22) or serratus plane block (n=21). The primary outcome was the proportion of patients with no complaints of pain 2 months post-BCS. The odds ratio (OR) was assessed, adjusting for axillary lymph node dissection. The secondary outcomes were pain severity 24 hours and 2 months post-operation using the numerical rating scale score, and morphine consumption within 24 hours. The proportion of patients without pain 2 months post-BCS was significantly less with Pecs II block than in patients with serratus plane block (55% vs. 19%, adjusted OR, 5.04; 95% confidence interval, 1.26-20.07; P=0.02); the median [interquartile range] score for pain 2 months post-operation was also significantly lower with Pecs II block (Pecs II block 0.5 [0-1] vs. serratus plane block 1 [1-2]); P=0.03). Regarding post-BCS acute analgesia, the median [interquartile range] postoperative 24-hour pain score was 2 [1-3] and 3 [1.5-3.5], and the median morphine consumption within 24 hours was 1.5 [0.75-5.5] and 3 [1.5-10] mg in Pecs II block and serratus plane block (P=0.47 and P=0.11), respectively. This study suggests that Pecs II block prevents short-term post-BCS pain better than serratus plane block. However, further studies are needed in order to support this finding.

A single paravertebral injection via a needle vs. a catheter for the spreading to multiple intercostal levels: a randomized controlled trial.

PURPOSE: Thoracic paravertebral block (TPVB) provides a unilateral nerve block at multiple intercostal levels allowing injection of a local anesthetic into paravertebral space (PVS) via a needle or catheter. However, the most effective injection method remains unclear. This study compared the real-time spread of ropivacaine between two paravertebral injection methods using thoracoscopy. METHODS: Thirty-four patients scheduled for thoracoscopic surgery were randomly allocated into the Needle or Catheter groups, and performed transverse in-plane ultrasound-guided TPVB. The Needle group received 20 ml of 0.5% ropivacaine via a needle placed into the lateral edge of PVS; the Catheter group received the same dose of ropivacaine via a catheter inserted 5 cm into PVS. The primary outcome was the spreading pattern of ropivacaine in each group. The secondary outcome was intraoperative vasopressor requirement after paravertebral injection. RESULTS: In the Needle group, all cases showed ropivacaine spread to multiple intercostal levels, mainly across the ribs. Contrastingly, the Catheter group showed variable spreading patterns; multiple intercostal levels (n = 10) [across the ribs (n = 4), anterolateral aspect of the vertebral bodies (n = 6)] or unobservable spreading (no change; n = 7) (P = 0.007). Vasopressors were required in two and ten cases in the Needle and Catheter groups, respectively (P = 0.010). CONCLUSION: Paravertebral injection via a needle typically resulted in spreading to multiple intercostal levels, especially across the ribs on the peripheral side of injection site, whereas injection via a catheter resulted in variable spreading patterns. Therefore, injections via needles are more stable.

Dietary exposure to acrylamide in a group of Japanese adults based on 24-hour duplicate diet samples.

Acrylamide is a probable human carcinogen and known human neurotoxin that can be generated in food through heating. Using a mathematical modelling approach, our previous study estimated long-term average dietary exposure to acrylamide in the Japanese people; however, the validity of these estimates remained unknown. Here, we aimed to obtain a more accurate estimate of acrylamide exposure that would reflect the usual practice of heat processing and consumption of foods in the population. We collected duplicate diet samples and dietary records during 24 h from a group of Japanese adults. A total of 110 duplicate diet samples were analysed for acrylamide by LC-MS/MS. Data from individual dietary records were used to examine the association between dietary acrylamide exposure and consumption of selected food groups (e.g., coffee, tea, confectioneries, and vegetables prepared at high temperature [deep-frying, stir-frying, sautéing, and baking]). Of the 110 homogenised diet samples, 108 contained detectable levels of acrylamide. Dietary exposure to acrylamide ranged from 8 to 1582 ng/kg body weight (bw)/day, with the mean value of 215 ng/kg-bw/day and median value of 143 ng/kg-bw/day. This mean value was higher than the value we previously estimated for Japanese adults using a mathematical approach. Multiple linear regression analysis showed log dietary acrylamide exposure was significantly associated with consumption of coffee and vegetables prepared at high temperature during 24-hr of sampling (adj. R2 = 0.250, p < 0.001). We revealed significant difference in dietary acrylamide exposure between participants who had coffee and vegetables prepared at high temperature (median, 169 ng/kg-bw/day; range, 35-1224 ng/kg-bw/day, n = 42) and those who had none of them (median, 75 ng/kg-bw/day; range, 8-311 ng/kg-bw/day, n = 15) (Steel-Dwass test, p < 0.05).

Local anesthetic spread into the paravertebral space with two types of quadratus lumborum blocks: a crossover volunteer study.

PURPOSE: Previous work showed that 20 mL of local anesthetic (LA) did not spread into the paravertebral space (PVS) via the intramuscular quadratus lumborum block (QLBi). If spread of LA into the PVS can be achieved by increasing the total LA volume, QLBi can be more effective. We hypothesized that a larger volume of LA for the QLBi would spread into the PVS. METHODS: This crossover volunteer study included five healthy men. For comparison, both the ultrasound-guided QLB type 2 (QLB2) and QLBi were employed on opposite sides of each volunteer, and the spread of LA solution (0.7 mL/kg) mixed with contrast media in the PVS was assessed 1 h after the first injection using magnetic resonance imaging. Sensory loss was evaluated by pinprick 90 min post-injection. Each volunteer underwent both QLB types, and the same procedures were administered on opposite sides 7 days after the first experiment. RESULTS: In total, 20 QLB blocks (10 QLB2 and 10 QLBi) were performed. LA did not spread into the PVS after the QLBi. The sensory block area included the lower abdomen after the QLB2, but not after the QLBi. The sensory block area did not extend to the upper abdominal region or the midline of the lower abdomen with either block method. CONCLUSION: LA administered by the QLB2 spreads into the PVS of T10-T12, resulting in lower and lateral abdominal sensory loss. In contrast, LA administered by the QLBi does not spread into the PVS and results in only lateral abdominal sensory loss.

Improving the side-to-side stapled anastomosis: comparison of staplers for robust crotch formation.

BACKGROUND: Few studies have investigated the burst pressure of side-to-side anastomoses comparing different stapling devices that are commercially available. OBJECTIVES: We conducted side-to-side anastomoses with a variety of staplers and compared burst pressure in the crotch of the anastomoses. SETTING: Nagoya City East Medical Center. METHODS: We conducted side-to-side anastomoses with 9 staplers with different shapes and forms. Fresh pig small intestines were used. A side-to-side anastomosis was performed between 2 intestine specimens using a linear stapler. The burst pressure of the anastomosis was recorded. RESULTS: In total, 45 staplers were used for this experiment. The site of leakage in all cases was the crotch. Regarding the influence of the number of staple rows, the burst pressure in 3-row staplers was significantly higher than in 2-row staplers. With regard to the relationship between staple height and burst pressure, staples with a height slightly shorter than the intestinal thickness showed the highest burst pressure. In a comparison of staplers with uniform staple heights and stamplers with staples of 3 different heights, the latter had significantly lower burst pressures. Neoveil significantly increased the burst pressure in the crotch and contributed to the highest burst pressure of all the staplers used in this experiment. CONCLUSIONS: In this experiment, we defined the important factors that influence burst pressure at the crotch of a stapled, side-to-side anastomosis. These factors include the number of staple rows, the height of the staple compared with the thickness of the tissue, uniformity of staple height, and reinforcement of the staple line. In any surgical case requiring intestinal anastomosis, selection of a stapler is a critical step.

Eversion stripping of the esophagus with intraesophageal insufflation-A case report.

INTRODUCTION: Patients with esophageal cancer frequently cannot tolerate thoracotomy due to their overall debilitated condition. Moreover, some patients have severe adhesions in the thoracic cavity. Eversion stripping of the esophagus is an option for resection in these patients. PRESENTATION OF CASE: A 64-year-old man was admitted to our institution with the chief complaint of epigastric pain. Endoscopic examination showed a protruding lesion 22cm from the incisors, with a superficial and circumferential mucosal irregularity on the distal side of the lesion. Biopsy revealed squamous cell carcinoma. Clinical stage was T1b(sm)N0M0, cStage I. In addition to the poor pulmonary status of the patient, adhesions in the intrathoracic cavity were predicted. The decision was made to perform esophageal resection without a thoracotomy. In order to ensure complete invagination of the esophagus, the esophagus was insufflated prior to stripping. The stripping process was observed with a gastroscope. During the stripping, the esophagus did not bunch up, and stripping was smooth and with minimal resistance. DISCUSSION: The stripping resection of the esophagus is an important option for the esophageal surgeon. In this case report, we describe a new eversion stripping method of the esophagus. This easy and reliable stripping method incorporates intraesophageal insufflation. CONCLUSION: The indications for blunt esophageal dissection without thoracotomy have been decreasing. On the other hand, our method seems to be useful in optimal case of stripping of esophagus.

Resection of the Gastric Tube Reconstructed through the Retrosternal Route without Sternotomy.

With advances of combined modality therapy, prognoses in esophageal cancer have been improving. After resection of esophageal cancer, the development of gastric tube cancer is a risk. While such cancer in an early stage can be cured endoscopically, total gastric tube resection is indicated in advanced stages. A 68-year-old man underwent subtotal esophagectomy reconstructed with a gastric tube through the retrosternal route. Gastric cancer was found one and a half years postoperatively. The gastric tube was resected without sternotomy. This is the first report of a patient undergoing resection of the gastric tube reconstructed through the retrosternal route without sternotomy.

A randomized controlled trial comparing paravertebral block via the surgical field with thoracic epidural block using ropivacaine for post-thoracotomy pain relief.

PURPOSE: We conducted a comparative study to evaluate analgesic efficacy between paravertebral block via the surgical field (PVB-sf), in which the catheter was inserted into the ventral side of the sympathetic trunk in the paravertebral space by a thoracic surgeon under thoracoscopic visualization, and epidural block (Epi) using ropivacaine for post-thoracotomy pain relief. METHODS: Lung cancer patients scheduled for lobectomy via thoracotomy were randomly allocated to receive either PVB-sf or Epi (n = 36 per group). Before thoracotomy closure, 0.375% ropivacaine was administered as a bolus (PVB-sf, 20 mL; Epi, 5 mL), followed by a 300-mL continuous infusion of 0.2% ropivacaine at 5 mL/h. Postoperative pain was assessed using a visual analog scale (VAS) score at various time points, including the primary endpoint of 2 h after ropivacaine bolus injection. Sensory block area, vital signs, serum ropivacaine concentrations, and side effects were also evaluated. RESULTS: The Epi group showed significantly lower VAS scores and blood pressure and a wider sensory block area than the PVB-sf group at all evaluation time points. While the mean serum ropivacaine concentration in the PVB-sf group was significantly higher than that in the Epi group until 1 h after injection of the ropivacaine bolus, there was no significant difference at any subsequent assessment point. The incidence of side effects was similar between the groups. CONCLUSION: The Epi was superior to PVB-sf for the management of post-thoracotomy pain in this patient cohort. The number of dermatomes anaesthetized by Epi was greater than that anaesthetized by PVB-sf. No difference in complication rates was observed between the two groups.

[Ultrasound-guided Truncal Block for Abdominal Surgery: Present and Future Perspectives].

Patients undergoing abdominal surgery can experi- ence severe pain due to the abdominal wall incision. Epidural anesthesia has been considered as the gold standard for perioperative analgesia in abdominal sur- gery. However, currently, many patients receive pro- phylactic anticoagulation therapy preoperatively with potential complications. For such cases, while epidural anesthesia is contraindicated, the use of ultrasound- guided peripheral nerve block is increasing. In abdomi- nal surgery, ultrasound-guided rectus sheath block and transversus abdominis plane block are commonly used for perioperative analgesia. The use of ultrasound ren- ders these block techniques safe and reliable. Cur- rently, a new abdominal peripheral nerve block, qua- dratus lumborum block, is gaining attention because it is thought to have a wider range of analgesia and a longer duration of effect As the analgesic properties of these blocks are limited in extent and duration, it is important to select the appropriate approach. Ultrasound-guided abdominal trunk block can con- tribute to perioperative multimodal analgesia.

Breakage and retention of thoracic paravertebral catheter: a case report.

BACKGROUND: Paravertebral catheters are generally inserted and removed without complications. However, catheter breakage occurs rarely. This is the first report describing breakage of a thoracic paravertebral catheter and retention of the catheter fragment within the patient. CASE PRESENTATION: A 65-year-old female patient complained of an unusual sensation in her back during postoperative chemotherapy for lung cancer. A catheter fragment was identified in the soft tissues of the back on computed tomography. The paravertebral catheter had been placed 2 years prior left lower lobectomy. The patient had neither neurological symptoms nor infection signs around the fragment. However, the potential side effects of chemotherapy, including coagulopathy and immunosuppression, increased the risk of late-onset hematoma and abscess formation around the fragment. Therefore, we surgically removed the catheter fragment. Analysis of the fragment revealed that the catheter had been severed by the cutting edge of the Tuohy needle or the suture needle. CONCLUSION: In this report, a paravertebral catheter fragment was retained in the posterior mediastinum for 2 years. The catheter was likely damaged during the insertion procedure. We suggest that catheters should not be withdrawn through the Tuohy needle, but be withdrawn together with the Tuohy needle. Although secure fixation of the catheter can be achieved with sutures, to reduce the risk of damage to the catheter, alternative methods, such as surgical tapes or skin glue should be considered. After removal of a catheter, its tip should be checked to ensure that the entire catheter has been completely removed. If a catheter fragment is retained within the patient, removal of the fragment should be considered according to the patient's condition and risks.

Recent decline of DDTs among several organochlorine pesticides in background air in East Asia.

Hexachlorocyclohexanes (HCHs), chlordanes (CHLs), and dichlorodiphenyltrichloroethanes (DDTs) in air-mass outflows from East Asia were recorded monthly from April 2009 to March 2014 at Cape Hedo in Japan. These organochlorine pesticides (OCPs) were collected by a high volume air sampler equipped with a quartz fiber filter, a polyurethane foam plug, and activated carbon fiber and analyzed by using a gas chromatograph-high resolution mass spectrometer. The overall (and geometric mean ± SD) concentration over the period was 4.9-43 pg m(-3) (15 ± 7.8 pg m(-3)) in HCHs (sum of α-/ß-/γ-/δ-HCH), 1.5-83 pg m(-3) (8.8 ± 11 pg m(-3)) in CHLs (sum of cis-/trans-chlordane, cis-/trans-nonachlor, and oxychlordane), and 0.71-16 pg m(-3) (2.5 ± 2.0 pg m(-3)) in DDTs (sum of o,p'-/p,p'-DDD, o,p'-/p,p'-DDE, and o,p'-/p,p'-DDT). Clear seasonal changes, i.e. higher in summer and lower in winter, were observed in HCHs and CHLs, suggesting the dominant effect of temperature-dependence, secondary sources in these OCPs. DDT concentration as well as the ratio of (o,p'-DDT + p,p'-DDT) to total DDTs, on the other hand, showed clear a declining trend during the five year sampling period, suggesting the decrease of input of newly produced DDTs in the regional environment by reflecting recent activities in the East Asian region to eliminate production and use of DDTs under the Stockholm Convention.

Brain regions and monoaminergic neurotransmitters that are involved in mouse ambulatory activity promoted by bupropion.

Bupropion (BUP), a substituted phenyl-ethylamine, has been utilized for the treatment of depression and for smoking cessation, however, one concern is that BUP may increase a risk of psychosis similar to other substituted phenyl-ethylamine amphetamine (AMPH) and methamphetamine (MetAMPH). BUP promotes ambulation in mice and causes behavioral sensitization on the ambulation-promoting effect when repeatedly administered as well as AMPH and MetAMPH. The present study aimed to elucidate brain regions and monoaminergic neurotransmitters that are involved in the ambulation-promoting effect of BUP. c-Fos-like immunoreactivity (c-Fos-IR) mapping in brain in combination with measuring ambulatory activity was conducted to determine brain region(s) that is involved in the ambulatory effect of BUP. Three kinds of statistical analyses for c-Fos-IR in 24 brain regions consistently showed that c-Fos-IR in the Caudate putamen (CPu) is positively correlated with the ambulatory response to BUP. In addition, multiple regression analysis indicated that the ambulatory response is a function of c-Fos-IR not only in the CPu but also in the lateral septum nucleus (LS), median raphe nucleus (MnR), lateral globus pallidus (LGP), medial globus pallidus (MGP), locus coeruleus (LC) and ventral hypothalamic nucleus (VMH). Effects of BUP on monoaminergic neurotransmitters in the CPu were examined using in vivo microdialysis method, as the pharmacological experiments indicated that monoaminergic neurotransmitters, dopamine (DA) in particular, mediate the ambulatory response to BUP. Response of DA in the CPu to BUP was parallel to the ambulatory response, showing that DA in the CPu is involved in the ambulatory response to BUP. The present study also suggests that other brain regions such as the LC, the origin nucleus of norepinephrine (NE) neurons, and another neurotransmitter NE may also play some roles for the ambulatory response to BUP, however, further studies are needed to elucidate the roles.

Rapid automatic identification and quantification of compounds in complex matrices using comprehensive two-dimensional gas chromatography coupled to high resolution time-of-flight mass spectrometry with a peak sentinel tool.

Comprehensive two-dimensional gas chromatography coupled to mass spectrometry (GC×GC-MS) is a powerful tool for comprehensive analysis of organic pollutants. In this study, we developed a powerful analytical method using GC×GC for rapid and accurate identification and quantification of compounds in environmental samples with complex matrices. Specifically, we have developed an automatic peak sentinel tool, T-SEN, with free programming software, R. The tool, which consists of a simple algorithm for on peak finding and peak shape identification, allows rapid screening of target compounds, even for large data sets from GC×GC coupled to high resolution time of flight mass spectrometry (HRTOFMS). The software tool automatically assigns and quantifies compounds that are listed in user databases. T-SEN works on a typical 64 bit workstation, and the reference calculation speed is 10-20 min for approximately 170 compounds for peak finding (five ion count setting) and integration from 1-2GB of sample data acquired by GC×GC-HRTOFMS. We analyzed and quantified 17 PCDD/F congeners and 24 PCB congeners in a crude lake sediment extract by both GC×GC coupled to quadrupole mass spectrometry (qMS) and GC×GC-HRTOFMS with T-SEN. While GC×GC-qMS with T-SEN resulted in false identification and inaccurate quantification, GC×GC-HRTOFMS with T-SEN provided correct identification and accurate quantification of compounds without sample pre-treatment. The differences between the values measured by GC×GC-HRTOFMS with T-SEN and the certified values for the certified reference material ranged from 7.3 to 36.9% for compounds with concentrations above the limit of quantification. False positives/negatives were not observed, except for when co-elution occurred. The technique of GC×GC-HRTOFMS in combination with T-SEN provides rapid and accurate screening and represents a powerful new approach for comprehensive analysis.

Selective extraction of halogenated compounds from data measured by comprehensive multidimensional gas chromatography/high resolution time-of-flight mass spectrometry for non-target analysis of environmental and biological samples.

We developed a method that selectively extracts a subset from comprehensive 2D gas chromatography (GC×GC) and high-resolution time-of-flight mass spectrometry (HRTOFMS) data to detect and identify trace levels of organohalogens. The data were obtained by measuring several environmental and biological samples, namely fly ash, soil, sediment, the atmosphere, and human urine. For global analysis, some samples were measured without purification. By using our novel software, the mass spectra of organochlorines or organobromines were then extracted into a data subset under high mass accuracy conditions that were approximately equivalent to a mass resolution of 6000 for some samples. Mass defect filtering as pre-screening for the data extraction was very effective in removing the mass spectra of hydrocarbons. Those results showed that data obtained with HRTOFMS are valuable for global analysis of organohalogens, and probably of other compounds if specific data extraction methods can be devised.

Global and selective detection of organohalogens in environmental samples by comprehensive two-dimensional gas chromatography-tandem mass spectrometry and high-resolution time-of-flight mass spectrometry.

We successfully detected halogenated compounds from several kinds of environmental samples by using a comprehensive two-dimensional gas chromatograph coupled with a tandem mass spectrometer (GC×GC-MS/MS). For the global detection of organohalogens, fly ash sample extracts were directly measured without any cleanup process. The global and selective detection of halogenated compounds was achieved by neutral loss scans of chlorine, bromine and/or fluorine using an MS/MS. It was also possible to search for and identify compounds using two-dimensional mass chromatograms and mass profiles obtained from measurements of the same sample with a GC×GC-high resolution time-of-flight mass spectrometer (HRTofMS) under the same conditions as those used for the GC×GC-MS/MS. In this study, novel software tools were also developed to help find target (halogenated) compounds in the data provided by a GC×GC-HRTofMS. As a result, many dioxin and polychlorinated biphenyl congeners and many other halogenated compounds were found in fly ash extract and sediment samples. By extracting the desired information, which concerned organohalogens in this study, from huge quantities of data with the GC×GC-HRTofMS, we reveal the possibility of realizing the total global detection of compounds with one GC measurement of a sample without any pre-treatment.

Spinal cord stimulation markedly ameliorated refractory neuropathic pain in transthyretin Val30Met familial amyloid polyneuropathy.

Although spinal cord stimulation has been reported to be effective for controlling neuropathic pain in diabetic neuropathy, it has rarely been investigated in other peripheral neuropathies. We describe, for the first time, the efficacy of spinal cord stimulation for refractory neuropathic pain in a patient with transthyretin Val30Met associated familial amyloid polyneuropathy (FAP ATTR Val30Met). A 72-year-old man was diagnosed as having FAP ATTR Val30Met when he was 70 years old. He had been complained of burning pain in the distal portion of his bilateral lower limbs since he was 69 years old. Because conventional symptomatic therapies, including nonsteroidal anti-inflammatory drugs, antiepileptic drugs, and tricyclic antidepressants did not ameliorate pain, he underwent bilateral lumbar spinal cord electrical stimulation at high frequency and low voltage at the level of Th12 vertebral body and this was markedly effective. Our case expands the application of spinal cord stimulation, which should be considered as an alternative therapeutic approach for relief of neuropathic pain, which can be extremely distressful for patients and may lead to an impaired quality of life.

Serum concentration of lidocaine after transversus abdominis plane block.

We measured the serum concentration of lidocaine after transversus abdominis plane (TAP) block with 40 ml of 1% lidocaine in 12 patients under general anesthesia, using a fluorescence polarization immunoassay. The peak mean serum concentration of lidocaine occurred 30 min after the block (3.6 +/- 0.7 microg x ml(-1)). The highest concentration of lidocaine (5.microg x ml(-1)) was recorded 15 min after the block. These results indicate that a TAP block can potentially cause systemic toxicity of a local anesthetic. The analgesic effect of the TAP block may partially depend on the rise in serum concentration of the local anesthetic.

[Ultrasound-guided femoral nerve block].

Femoral nerve block is well suited for surgery on the anterior aspect of the thigh and knee. The primary indication of continuous femoral nerve block is pain management after major femoral or knee surgery. Ultrasound image guidance for femoral nerve block can improve block success rate and decrease complications. We describe the ultrasound scanning, needling technique, and catheter insertion technique for single-dose technique and continuous infusion technique.