Effects of local infiltration analgesia for posterior knee pain after total knee arthroplasty: comparison with sciatic nerve block

Background

Although femoral nerve block provides good analgesia after total knee arthroplasty (TKA), residual posterior knee pain may decrease patient satisfaction. We compared the efficacy of periarticular infiltration analgesia (PIA) and sciatic nerve block (SNB) for posterior knee pain.

Methods

Forty-nine patients scheduled for TKA were prospectively randomized into the PIA group (n = 25) or SNB group (n = 24) and received general anesthesia with ultrasound-guided femoral nerve block (FNB). In the PIA group, 60 ml 0.5 % ropivacaine and 0.3 mg epinephrine were injected intraoperatively into the periarticular soft tissue before inserting the components. In the SNB group, patients received ultrasound-guided SNB with 20 ml 0.375 % ropivacaine and periarticular infiltration with 20 ml normal saline and 0.3 mg epinephrine. We evaluated postoperative pain scores, posterior knee pain, frequency of rescue analgesics for 36 h, and performance time of PIA and SNB.

Results

Visual analogue pain scores at 12–24 h were significantly lower in the PIA group than in the SNB group (p < 0.05). The majority of patients had no posterior knee pain. There were no significant differences between the groups in frequency and time of first administration of rescue analgesics and in side effects. Time for performance of periarticular infiltration was significantly shorter than that for SNB (p < 0.05). The dose of intraoperative remifentanil was significantly lower in the SNB group than in the PIA group (p < 0.001).

Conclusions

The combination of FNB and PIA provides sufficient analgesia after TKA. The rapid and convenient periarticular infiltration technique could be a good alternative to SNB.     

Case series: ultrasound-guided supraclavicular block using a curvilinear probe in 104 day-case hand surgery patients

Purpose

To report our experiences regarding the implementation of a combined ultrasound and nerve stimulation guidance technique for supraclavicular blockade in day-case hand surgery patients at our institution.

Clinical features

We retrospectively reviewed 104 patient charts from the first 6 months of our clinical practice of using this block approach for upper extremity surgery. Block success, completion and recovery time, post-block analgesia requirement, acute complication rate, and duration of hospital stay were evaluated and categorized based on the practitioner who performed the block (fellow/staff anesthesiologists and residents), as well as the body mass index of the patient (when available). During the performance of each block, the brachial plexus was viewed using a curvilinear probe, and the needle was advanced in-plane in an anterolateral-to-posteromedial direction. The plexus, needle, and spread of local anesthetic could be clearly visualized in each case. Surgical regional anesthesia was achieved in 94.2% of blocks. The block was the sole method of postoperative analgesia in 85.6% of patients, and the overall block completion time was 20.2 ± 9.2 min. There were no occurrences of clinical pneumothorax during the study period.

Conclusions

We report our successful experience using ultrasound guidance and nerve stimulation during supraclavicular blockade. The curvilinear probe enables a large field of view, adequate resolution in larger patients, and excellent needle visibility that allows access to the plexus while avoiding the pleura and subclavian artery.     

Perivascular brachial plexus block. Ultrasound versus nerve stimulator

Background

Optimizing the needle position using ultrasound (US) instead of electrical nerve stimulation (NSt) is increasingly common for perivascular brachial plexus block. These two methods were compared in a prospective, randomized, single-blinded controlled trial regarding effectiveness and time of onset of peripheral nerve blockade.

Methods

After puncture (penetration of neurovascular sheath and complete insertion of needle) 56 patients were randomly assigned to either the US group (finding the needle tip in transpectoral section, short axis, correction of needle position if local anesthetic spread was insufficient) or the NSt group (target impulse reaction in median, ulnar or radial nerve of 0.3?mA/0.1?ms, if necessary correction of position before injection of local anesthetic) to verify the needle position. All patients received 500?mg 1% mepivacaine. Sensory and motor blocks were tested by single nerve measurements (SNM) 5, 10 and 20?min after finishing the injection, where 0 represents minimal and 2 maximal success of the block.

Results

Single nerve measurements were analyzed using repeated measures ANOVA. The mean results of cumulative SNMs were significantly higher in the US group at all measurement times. Sensitivity US/NSt: 5?min: 3.36±2.32/2.63±1.87; 10?min: 5.45±2.41/4.21±2.45; 20?min: 7.30±2.02/6.43±2.43, p=0.015, motor function US/NSt: 5?min: 3.91±1.81/3.02±1.67; 10?min: 5.27±1.66/4.05±1.70; 20?min: 6.64±1.37/5.50±1.90, p<0.001. At the beginning of surgery complete nerve blockade was achieved in 89% in the US group and 68% in the NSt group (p=0.006), 3 (US) versus 7 (NSt) patients needed supplementation and 3 (US) versus 11 (NSt) patients needed general anesthesia (p=0.022). To achieve the nerve block took approximately 1?min more in the US group (p=0.003).

Conclusion

The use of ultrasound in perivascular brachial plexus blocks leads to significantly higher success rates and shorter times of onset.     

No change in impedance upon intravascular injection of D5W

Purpose

Electrical impedance increases following test injections of non-conducting solutions around nerves; however, this increase should diminish rapidly with intravascular needle placement, wherein the systemic circulation will dissipate the solution. For this observational study, we hypothesized that the impedance increases significantly at the perineural space after an injection of 5% dextrose in water (D5W), but that it does not increase correspondingly at the intravascular location

Methods

After Ethics Research Board approval, electrical impedance was measured by a nerve stimulator displaying resistance, Stimuplex® HNS 12, before and during (30 sec) an injection of D5W 3 mL: 1) during intravenous cannula placement using an insulated stimulating needle sheathed in its plastic cannula, MultiSet NanoLine with 18G needle; and 2) during needle placement (Pajunk 22G insulated) for an ultrasound-guided supraclavicular block in patients undergoing hand surgery. The impedance changes at each location were analyzed and compared.

Results

Data were collected from 16 patients. Baseline impedance was lower intravascularly (mean 16.5 ± standard deviation 7.2 kΩ) compared with perineurally (23.5 ± 8.3 kΩ) (P = 0.037). Peak impedance after intravascular D5W injection was 20.1 ± 6.8 kΩ, which was not a significant change (P = 0.15). In contrast, peak impedance after perineural D5W injection was 58.6 ± 29.1 kΩ, an increase of 35.1 ± 26.4 kΩ (155 ± 117%), and then it reached a plateau of 36.7 ± 19.6 kΩ. The increase in impedance was significantly greater at the perineural location (P < 0.0001).

Conclusion

The absence of a significant increase in impedance upon injection of D5W prior to injection of local anesthetic may provide useful information to warn of intravascular injection.     

Single-dose Spinalanästhesie mit einer Mischung aus Bupivacain 0,5% isobar und Mepivacain 4% hyperbar

Background: Single-dose spinal anaesthesia with hyperbaric local anaesthetic provides profound analgesia and motor blockade and allows exact assessment of the analgesic level. The present prospective, randomised study compares a mixture of plain 0.5% bupivacaine and hyperbaric 4% mepivacaine with hyperbaric 0.5% bupivacaine with regard to onset time of analgesia and duration of the sensory and motor blockade. Methods: One hundred and twenty-two orthopaedic patients (69 m/53 f, aged 20–91 years) scheduled for elective lower limb surgery under spinal anaesthesia were randomly allocated to one of two groups. In group 1, 67 patients received a 1:1 mixture of plain 0.5% bupivacaine and hyperbaric 4% mepivacaine (density: 1,015 kg/m³, 37° C). In group 2, 55 patients received hyperbaric 0.5% bupivacaine (density: 1,021). The lumbar puncture was performed between L3 and L5 using a 26 G Quincke needle through a 20 G introducer with the patients either in the sitting or lateral position. The local anaesthetic was administered with an injection speed of 1 ml per 5 s. Patients with a body height <160 cm received 2.0 ml, those 160–180 cm 3,0 ml, and those >180 cm 4.0 ml. The level of analgesia was registered every minute by pin-prick until the maximal analgesic level was reached. The time of regression of analgesia to the level of T 12 and regression of the motor block to Bromage scale 3 was registered. The data were analysed using Student’s t-test with P<0.05 considered as significant. Results: Demographic data did not differ between groups. In group 1, the onset time of analgesia was faster than in group 2 (8±3 vs. 14±5 min, P<0.001). While in group 1 the onset time of analgesia was faster in patients injected sitting compared to those in the lateral position (p<0.05), there was no position-related difference in group 2. The groups also did not differ with respect to the maximal level of analgesia and the duration of sensory and motor blockade. Conclusions: The local anaesthetic mixture may be preferred to hyperbaric 0.5% bupivacaine in patients requiring a fast onset of analgesia associated with a 2–3 h duration of sensory and motor block.     

The parasacral sciatic nerve block does not induce anesthesia of the obturator nerve

Purpose

The ability of the parasacral sciatic nerve block (PSNB) to induce anesthesia of the obturator nerve remains controversial. Our objective was to evaluate the anesthesia of the obturator nerve after a PSNB.

Methods

Forty patients scheduled to undergo knee surgery (anterior cruciate ligament reconstruction) were included in this prospective, randomized, controlled study. Patients were randomized to receive PSNB alone (control group, n = 20) or PSNB in combination with an obturator nerve block (obturator group, n = 20). After evaluation for 30 min, the two groups received a femoral nerve block, and patients were taken to surgery. The obturator nerve blockade was assessed by measurement of adductor strength at baseline (T0) and every 10 min during the 30-min evaluation (T10, T20, and T30). Pain scores after tourniquet inflation and during surgery were compared between the two groups. The requirement for additional intravenous analgesia and/or sedation was also recorded.

Results

The two groups had comparable demographic and surgical characteristics. Four patients were excluded from the study because of PSNB or femoral nerve block failure. The adductor strength values were similar between groups at T0 but were significantly lower in the obturator group at T10, T20, and T30 (p < 0.0001). Patients in the obturator group reported less pain than those in the control group (p < 0.05). They also required less additional intravenous sedation and/or analgesia (p < 0.05).

Conclusion

This clinical study demonstrated that the PSNB is an unreliable means of inducing anesthesia of the obturator nerve and emphasizes the need to block this nerve separately to induce adequate analgesia during knee surgery.     

Effect of ultrasound-guided intercostal nerve block on postoperative pain after percutaneous nephrolithotomy

Background

The aim of the study was to investigate the effect of preoperative ultrasound-guided (US) intercostal nerve block (ICNB) in the 11th and 12th intercostal spaces on postoperative pain control and tramadol consumption in patients undergoing percutaneous nephrolithotomy (PCNL).

Methods

After obtaining ethical committee approval and written informed patient consent, 40 patients were randomly allocated to the ICNB group or the control group. For the ICNB group US-guided ICNB was performed with 0.5?% bupivacaine and 1/200,000 epinephrine at the 11th and 12th intercostal spaces after premedication. A sham block was performed for the control group and postoperative pain and tramadol consumption were recorded by anesthesiologists blinded to the treatment.

Results

Postoperative visual analog scale scores at all follow-up times were found to be significantly lower in the ICNB group than in the control group (p?<?0.05). The mean 24 h intravenous tramadol consumption was 97.5?±?39.5 mg for the ICNB group which was significantly lower than the 199.7?±?77.6 mg recorded for the control group (p?<?0.05).

Conclusion

In PCNL with nephrostomy tube placement US-guided ICNB performed at the 11th and 12th intercostal spaces provided effective analgesia.     

Elektrische Nervenstimulation bei peripheren Nervenblockaden

Background

The use of nerve stimulation is a common standard procedure for peripheral nerve blocks. However, ultrasound guidance is increasingly being used as an alternative. This study explored the relationship between needle positioning defined by ultrasound guidance and the electrical nerve stimulation before and after injection of 5% glucose solution (G5%).

Patients and methods

After obtaining permission from the ethics committee, 60 patients were enrolled in the study and the results from 51 patients could be analyzed. For sonographically defined correct needle placement the lowest electrical threshold of the elicited motor responses before and after injection of 1 ml G5% was determined.

Results

In 76% of cases nerve structures could be visualized with high quality and 90% of the blocks were successful. Only 29% of patients with a successful block showed a motor response with a stimulation current ≤0.5 mA. There was a relationship only between the quality of the visualization and the success of the blockade. Addition of G5% did not result in significant changes in stimulation thresholds.

Conclusion

With the protocol used the success of a blockade depends only on the quality of visualization. With correct ultrasound-guided needle tip positioning the electrical information seems to be skewed and doubtful.     

Ropivacainevs bupivacaine in major surgery in infants

Purpose

To assess and compare the onset time and duration of neuroblockade obtained after ropivacaine or bupivacaine in infants undergoing major abdominal surgery. We also evaluated the efficacy and safety of employing ropivacaine instead of bupivacaine to provide operative anesthesia and postoperative analgesia.

Methods

In a prospective double blind study 28 infants, aged 1–12 months, undergoing elective major abdominal surgery, were randomly allocated to receive, after induction of general anesthesia, either 0.7 ml· kg^?1 bupivacaine 0.25% (group B) or ropivacaine 0.2% (group R) via lumbar epidural block. The onset time, total surgical time and duration of analgesia were recorded.

Results

No differences were noted in demographic data, hemodynamic variables or duration of surgery. The onset time for sensory blockade was 13.1 min ± 2.1 (group B) and 11.7 ± 2.4 min (group R). The duration of analgesia was 491 ± 291 (group R) and 456 min ± 247 (group B). Eight patients in group B and six in group R needed codeine and acetaminophen rescue on at least one occasion during the 24 hr study period. No major side effects were noted in either groups.

Conclusions

In infants undergoing major abdominal surgery under combined epidural/light general anesthesia, ropivacaine 0.2% produces sensory and motor blockade similar in onset, duration of action and efficacy to that obtained from an equal volume, 0.7 ml· kg^?1, of bupivacaine 0.25%.     

Sentinel Lymph Node Biopsy is Associated with Improved Survival in Merkel Cell Carcinoma

Background

Although sentinel lymph node biopsy (SNB) has become a standard for Merkel cell carcinoma (MCC), the impact on survival is unclear. To better define the staging and therapeutic value of SNB, we compared SNB with nodal observation.

Methods

Patients with clinical stage I and II MCC in the Surveillance, Epidemiology, and End Results (SEER) registry undergoing surgery between 2003 and 2009 were identified and divided into two groups—SNB and observation.

Results

A total of 1,193 patients met the inclusion criteria (SNB 474 and Observation 719). The median age was 78 years, and the majority were White (95.3 %), male (58.8 %), received radiation therapy (52.9 %) and had T1 tumors (65.3 %). Twenty-four percent had a positive SNB. SNB patients were younger (73 vs. 81 years; p < 0.0001), had T1 tumors (69.6 vs. 62.5 %; p = 0.04) and received radiotherapy (57.8 vs. 40 %; p < 0.0001). Among biopsy patients, a negative SNB was associated with improved 5-year MCC-specific survival (84.5 vs. 64.6 %; p < 0.0001). Univariate analysis demonstrated an increased 5-year MCC-specific survival for the SNB group versus the Observation group (79.2 vs. 73.8 %; p = 0.004), female gender (83.2 vs. 70.4 %; p = 0.0004), and lower T stage (p < 0.0001). On Cox regression, diminished survival was noted for the Observation group (risk ratio [RR] 1.43; p = 0.04), male gender (RR 2.06; p < 0.0001), and a higher T stage.

Conclusion

SNB for MCC provides prognostic information and is associated with a significant survival advantage.     

Distale Blockaden des N. ischiadicus

Background and objectives

The design of this study is related to an important current issue: should local anesthetics be intentionally injected into peripheral nerves? Answering this question is not possible without better knowledge regarding classical methods of nerve localization (e.g. cause of paresthesias and nerve stimulation technique). Have intraneural injections ever been avoided? This prospective, randomized comparison of distal sciatic nerve block with ultrasound guidance tested the hypothesis that intraneural injection of local anesthetics using the nerve stimulation technique is common and associated with a higher success rate.

Material and methods

In this study 250 adult patients were randomly allocated either to the nerve stimulation group (group NS, n?=?125) or to the ultrasound guidance group (group US, n?=?125). The sciatic nerve was anesthetized with 20 ml prilocaine 1% and 10 ml ropivacaine 0.75%. In the US group the goal was an intraepineural needle position. In the NS group progress of the block was observed by a second physician using ultrasound imaging but blinded for the investigator performing the nerve stimulation. The main outcome variables were time until readiness for surgery (performance time and onset time), success rate and frequency of paresthesias. In the NS group needle positions and corresponding stimulation thresholds were recorded.

Results

In both groups seven patients were excluded from further analysis because of protocol violation. In the NS group (n?=?118) the following needle positions were estimated: intraepineural (NS 1, n?=?51), extraparaneural (NS 2, n?=?33), needle tip dislocation from intraepineural to extraparaneural while injecting local anesthetic (NS 3, n?=?19) and other or not determined needle positions (n?=?15). Paresthesias indicated an intraneural needle position with an odds ratio of 27.4 (specificity 98.8%, sensitivity 45.9%). The success rate without supplementation was significantly higher in the US group (94.9% vs. 61.9%, p?<?0.001) and the time until readiness for surgery was significantly (p?<?0.001) shorter for successful blocks: 15.1 min (95% confidence interval CI 13.6–16.5 min) vs. 28 min (95% CI 24.9–31.1 min). In the NS subgroups the results were as follows (95% CI in brackets): NS1 88.2% and 22.7 min (19.5–25.9 min), NS2 24.2% and 43.3 min (35.5–51.1 min) and NS3 36.8% and 35.3 min (22.1–48.4 min).

Conclusions

For distal sciatic nerve blocks using the nerve stimulation technique, intraepineural injection of local anesthetics is common and associated with significant and clinically important higher success rates as well as shorter times until readiness for surgery. In both groups no block-related nerve damage was observed. The results indicate that for some blocks (e.g. sciatic, supraclavicular) perforation of the outer layers of connective tissue was always an important prerequisite for success using classical methods of nerve localization (cause of paresthesias and nerve stimulation technique). Additional nerve stimulation with an ultrasound-guided distal sciatic nerve block cannot make any additional contribution to the safety or success of the block. New insights concerning the architecture of the sciatic nerve are discussed and associated implications for the performance of distal ultrasound-guided sciatic nerve block are addressed.     

Ultrasound-guided versus computed tomography-controlled periradicular injections in the middle and lower cervical spine: a prospective randomized clinical trial

Purpose

We conducted this study to evaluate accuracy, time saving, radiation doses, safety, and pain relief of ultrasound (US)-guided periradicular injections versus computed tomography (CT)-controlled interventions in the cervical spine in a prospective randomized clinical trial.

Methods

Forty adult patients were consecutively enrolled and randomly assigned to either a US or a CT group. US-guided periradicular injections were performed on a standard ultrasound device using a broadband linear array transducer. By basically following the osseous landmarks for level definition in “in-plane techniques”, a spinal needle was advanced as near as possible to the intended, US-depicted nerve root. The respective needle tip positioning was then verified by CT. The control group underwent CT-guided injections, which were performed under standardized procedures using the CT-positioning laser function.

Results

The accuracy of US-guided interventions was 100 %. The mean time to final needle placement in the US group was 02:21 ± 01:43 min:s versus 10:33 ± 02:30 min:s in the CT group. The mean dose-length product radiation dose, including CT confirmation for study purposes only, was 25.1 ± 16.8 mGy cm for the US group and 132.5 ± 78.4 mGy cm for the CT group. Both groups showed the same significant visual analog scale decay (p < 0.05) without “inter-methodic” differences of pain relief (p > 0.05).

Conclusions

US-guided periradicular injections are accurate, result in a significant reduction of procedure expenditure under the avoidance of radiation and show the same therapeutic effect as CT-guided periradicular injections.     

Negligible Effect of Perioperative Epidural Analgesia Among Patients Undergoing Elective Gastric and Pancreatic Resections

Background

There are conflicting data regarding improvements in postoperative outcomes with perioperative epidural analgesia. We sought to examine the effect of perioperative epidural analgesia vs. intravenous narcotic analgesia on perioperative outcomes including pain control, morbidity, and mortality in patients undergoing gastric and pancreatic resections.

Methods

We evaluated 169 patients from 2007 to 2011 who underwent open gastric and pancreatic resections for malignancy at a university medical center. Emergency, traumatic, pediatric, enucleations, and disseminated cancer cases were excluded. Clinicopathologic data were reviewed among epidural (E) and non-epidural (NE) patients for their association with perioperative endpoints.

Results

One hundred twenty patients (71 %) received an epidural and 49 (29 %) did not. There were no significant differences (P?>?0.05) in mean pain scores at each of the four days (days 0–3) among the E (3.2?±?2.7, 3.2?±?2.3, 2.3?±?1.9, and 2.1?±?1.9, respectively) and NE patients (3.7?±?2.7, 3.4?±?1.9, 2.9?±?2.1, and 2.4?±?1.9, respectively). Within each of the E and NE patient groups, there were significant differences (P?<?0.0001) in mean pain scores from day 0 to day 3 (P?<?0.0001). Of the E patients, 69 % also received intravenous patient-controlled analgesia (PCA). Ileus (13 % E vs. 8 % NE), pneumonia (12 % E vs. 8 % NE), venous thromboembolism (6 % E vs. 4 % NE), length of stay [11.0?±?12.1 (8, 4–107) E vs. 12.2?±?10.7 (7, 3–54) NE], overall morbidity (36 % E vs. 39 % NE), and mortality (4 % E vs. 2 % NE) were not significantly different.

Conclusions

Routine use of epidurals in this group of patients does not appear to be superior to PCA.     

Minimally invasive surgery for esophageal cancer: a review on sentinel node concept

Background

Lymphoadenectomy is a cornerstone of esophageal cancer treatment, and sentinel node (SN) biopsy (SNB) might provide surgeons with an extra tool to limit unnecessarily extended lymphadenectomy and to implement a minimally invasive approach. The aim of our study was to review all the available literature on the use of SNB in esophageal surgery for malignancy.

Methods

The review was conducted according to the PRISMA guidelines. A systematic search was performed in PubMed, EMBASE, and the Cochrane database to identify all original articles on the role of SNB in esophageal cancer. Data on methodologies, tumor stage and localization, and results were summarized and used to address relevant clinical questions related to the application of the SNB technique in esophageal cancer.

Results

Twelve studies were included, with a total of 492 patients. Different methods for SN identification were used (radionuclide, blue dye, computed tomography [CT] lymphography). The pooled values estimated using the random-effects model were, respectively: technetium-99 m overall detection rate (DR) 0.970 (95 % CI 0.814–0.996), accuracy (ACC) 0.902 (95 % CI 0.736–0.968); blue-dye DR 0.971 (95 % CI 0.890–0.993), ACC 0.790 (95 % CI 0.681–0.870); and CT lymphoscintigraphy DR 0.970 (95 % CI 0.814–0.996), ACC 0.902 (95 % CI 0.736–0.968).

Conclusion

Based on these results, the concept of SN in esophageal cancer is technically feasible with an acceptable DR and ACC, and it might be applicable in the event of early-stage adenocarcinoma of the gastroesophageal junction in patients with a high surgical risk or in a patient where an endoscopic resection is taken into consideration. Further studies focused on a single tumor type and localizations are needed in order to predict the correct utilization of this concept in minimally invasive treatment of esophageal cancer.     

Steuerung der axillären Multiinjektionstechnik zur Plexusanästhesie

Background

Ultrasound guidance is still a young method in regional anesthesia when compared to nerve stimulation and only a few studies exist comparing these two techniques in an axillary multiple injection approach.

Aim

This prospective, randomized, observer-blinded study compared an ultrasound-guided (SONO) quadruple injection axillary block (out of plane, perineural) with a nerve stimulation-guided (STIM) triple injection axillary block for upper limb surgery.

Material and methods

A total of 60 patients were randomized to either the SONO (n?=?30) or STIM (n?=?30) group. For the block 40–50 ml mepivacaine 1.5?% (plexus) and 5–10 ml mepivacaine 0.5?% (subcutaneous in the medial skin of the arm) was used. Anesthesia time was recorded as the primary end point. After evaluation of block-related pain using a visual analog scale (VAS) a blinded observer tested sensory and motor function of the median nerve (MED), ulnar nerve (ULN), radial nerve (RAD), musculocutaneous nerve of the upper limb (MUC) and medial cutaneous nerve of the forearm (CAM) at defined times. The main outcome variable was onset time (defined loss of sensory/motor function).

Results

No differences were observed between the groups in terms of onset time (single nerves 10–20 min, plexus 20–25 min) and success rate (SONO 90?%, STIM 89?%). Patient satisfaction as measured by block-related pain score (VAS 2 cm), complications (vascular puncture SONO 7?%, STIM 11?%; paresthesia SONO 21?%, STIM 22?%) and patient acceptance (SONO 92?%, STIM 91?%) showed no differences. Performance time was shorter in the SONO group (6.68?±?1.72 min vs. 8.05?±?2.58, p?=?0.02).

Conclusion

Nerve stimulation-guided axillary plexus blocks performed by trained anesthesiologists may result in similar onset times and success rates compared to ultrasound-guided blocks.     

The role of electrical stimulation in ultrasound-guided subgluteal sciatic nerve block: a retrospective study on how response pattern and minimal evoked current affect the resultant blockade

Purpose

Nerve stimulation may be combined with ultrasound imaging for a block of deeply located nerves such as the sciatic nerve in the subgluteal region. At present, it is unknown how the use of nerve stimulation affects blockade after this nerve block. We retrospectively compared the effects of the two types of motor response and those of minimal evoked current above and below 0.5 mA on ultrasound-guided subgluteal sciatic nerve block using mepivacaine or ropivacaine, two local anesthetics with different onset time and duration.

Methods

We reviewed records and video images of patients who, from April 2008 until October 2011, received ultrasound-guided subgluteal sciatic nerve block combined with nerve stimulation using 20 ml of either 1.5 % mepivacaine with 1:400,000 epinephrine or 0.5 % ropivacaine. Sensory and motor blockade data for 30 min after the block and for the duration of the blockade were gathered. Patients for whom any data were missing, the video image was poor, and/or intraneural injection was observed during the block were excluded from the study. The same data were compared in two ways: regarding the motor response pattern between the response of the tibial nerve and the common peroneal nerve, and regarding the minimal current between low current (< 0.5 mA) and high current (≥0.5 mA). The primary endpoints were the onset and duration of blockade of the sciatic nerve block.

Results

We analyzed the data of 170 and 99 patients who received mepivacaine and ropivacaine, respectively. The progress of sensory and motor blockade as well as block duration was similar between different motor response patterns after both anesthetics. The proportion of patients who developed sensory block of the tibial nerve and motor block at 30 min was higher in the low minimal current group than in the other group receiving mepivacaine. Patients in the former group also had longer block duration. With ropivacaine, complete motor blockade was present at 30 min in a higher proportion of patients after lower minimal evoked current than after higher minimal evoked current.

Conclusion

When ultrasound-guided subgluteal sciatic nerve block was conducted with nerve stimulation, the motor response pattern did not markedly affect the progress of sensory or motor blockade or block duration. Lower minimal evoked current was associated with faster onset in sensory and motor block and longer block duration after mepivacaine and faster onset in motor block after ropivacaine. The clinical significance of this, however, has yet to be determined.     

Case report: Neurological deficit associated with intraneural needle placement without injection

Purpose

Recent reports of painless intraneural injection of low volumes of local anesthetic without subsequent neurological deficit have led to the suggestion that deliberate subepineural injection may be a safe and therefore acceptable practice.

Clinical features

This report describes a case where a venous cannulation needle inadvertently penetrated a patient’s median nerve. Sudden onset severe lancinating pain occurred in the median nerve sensory distribution. A subsequent thorough ultrasound examination showed the median nerve to be located immediately posterior to the targeted median cubital vein. New onset sensory symptoms (numbness, tingling, pain, and altered sensation to touch) in the distribution of the penetrated median nerve persisted for >6 weeks.

Conclusion

This report highlights the hazards of intraneural needle placement irrespective of an associated injection.     

Neurolytic celiac plexus block reduces occurrence and duration of terminal delirium in patients with pancreatic cancer

Purpose

WHO’s three step ladder sometimes cannot provide adequate pain relief for pancreatic cancer. Some patients develop terminal delirium (TD). The aim of this study was to test if the addition of a celiac plexus block (CPB) to pharmacotherapy could reduce the incidence of TD.

Methods

Pancreatic cancer patients under the care of our palliative-care team were investigated with regard to the duration and occurrence of TD, pain scores [numerical rating score (NRS)] and daily opioid dose. Between August 2007 to September 2008, 17 patients received only pharmacotherapy (control group). Then, we modified our guideline for analgesia, performing CPB 7 days after the first intervention of our team. Between October 2008 to September 2009, 19 patients received CPB.

Results

The opioid doses in CPB group were significantly lower both at 10 days after the first intervention (3 days after CPB) (27 ± 11 vs. 66 ± 82 mg; p = 0.029) and 2 days before death (37 ± 25 vs. 124 ± 117 mg; p = 0.009). NRS in the CPB group were significantly lower both at 10 days after the first intervention (0 [0–2] vs. 3 [2–5], p < 0.0001) and 2 days before death (1 [0–2] vs. 3 [1–4.5], p = 0.018). The occurrence and duration of TD in CPB group were both reduced (42 vs. 94 %, p = 0.019; and 1.8 ± 2.9 vs. 10.4 ± 7.5 days, p = 0.0003).

Conclusion

The duration and occurrence of TD and the pain severity were significantly less in pancreatic cancer patients who underwent neurolytic CPB.     

The Influence of Sentinel Lymph Node Biopsy on Survival for Intermediate-Thickness Melanoma

Background

The Multicenter Selective Lymphadenectomy Trial-1 (MSLT-1) failed to demonstrate a survival advantage for sentinel lymph node biopsy (SNB) in melanoma. This may have been secondary to inadequate statistical power. This study was designed to determine the impact of SNB on melanoma-specific survival (MSS) in a larger patient cohort.

Methods

From 2003–2008, patients with tumors 1–4 mm in thickness and clinically negative nodes were identified within the SEER registry. Propensity score was used to create two matched cohorts: those who underwent a wide excision with SNB or wide excision alone.

Result

A total of 15,274 met inclusion criteria and 7,910 comprised the match cohort. Average age was 67.4 years. The majority were male (62.3 %) and white (97.2 %). Primary tumors were most frequently nonulcerated (77.1 %), located on the extremity (42.3 %), and T2 (64.1 %). There were 3,955 patients in both the SNB and observation groups. There was no significant difference in gender, ethnicity, ulceration status, primary site, or T-classification between the groups. Improved 5-year MSS was associated with SNB (85.7 vs. 84.0 %), female gender (88.3 vs. 82.7 %), absence of ulceration (87.5 vs. 75.7 %), extremity location (87.4 %), T2 disease (88.6 vs. 77.9 %), and a negative SNB (88.9 vs. 64.8 %). The relationships between observation [hazard ratio (HR) 1.18], male gender (HR 1.33), ulceration (HR 1.77), head-and-neck location (HR 1.34), and T3 disease (HR 1.82) persisted on multivariate analysis.

Conclusions

Status of the sentinel node is the strongest predictor of survival in patients with intermediate thickness melanoma. SNB compared with observation was associated with a modest survival advantage.     

Does the addition of magnesium to bupivacaine improve postoperative analgesia of ultrasound-guided thoracic paravertebral block in patients undergoing thoracic surgery?

Purpose

Magnesium is a plentiful intracellular cation that has been reported to possess analgesic effect. The present study was aimed to see whether addition of magnesium to bupivacaine in thoracic paravertebral block (TPVB) improved the analgesic effect after thoracic surgery.

Materials and methods

Fifty adult patients undergoing elective open thoracic surgery were divided into two equal groups. Group I received 12 ml of 0.5 % bupivacaine plus 0.9 % saline (3 ml) whereas Group II received 12 ml of 0.5 % bupivacaine plus 150 mg magnesium sulphate (in 3 ml 0.9 % saline) for TPVB. The following parameters were assessed: onset, dermatomal levels and duration of sensory block, duration of analgesia, visual analogue scale (VAS) for pain, postoperative intravenous morphine consumption, pulmonary function tests (peak expiratory flow rate [PEFR], forced expiratory volume in 1 s [FEV1] and forced vital capacity [FVC]) before and 24 h after surgery, and complications from the drugs and technique.

Results

Group II patients showed a significantly longer sensory block duration (224.6 ± 59.3 vs 160.1 ± 55.2 min, P < 0.05), longer duration of analgesia (388.8 ± 70.6 vs 222.2 ± 61.6 min, P < 0.05), less VAS during the postoperative 48 h, less need for postoperative morphine (16.2 ± 7.4 vs 29.5 ± 11.1 mg, P < 0.05) and lower incidence of somnolence (0 [0 %] vs 5 [20 %], P < 0.05). Furthermore, postoperative pulmonary function tests (PEFR, FEV1 and FVC) were significantly better in Group II whereas there was no significant difference between both groups regarding the sensory block dermatomal level or hemodynamic data.

Conclusion

Addition of magnesium to bupivacaine in TPVB improved the analgesic effect of bupivacaine in patients undergoing thoracic surgery.