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Concept: Local anesthesia

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The use of peripheral nerve blocks for anesthesia and postoperative analgesia has increased significantly in recent years. Adjuvants are frequently added to local anesthetics to prolong analgesia following peripheral nerve blockade. Numerous randomized controlled trials and meta-analyses have examined the pros and cons of the use of various individual adjuvants.

Concepts: Randomized controlled trial, Anesthesia, Local anesthesia, Morphine, Ketamine, Local anesthetic, Anesthetic, Nerve block

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Local infiltration analgesia (LIA) with liposomal bupivacaine (LB) in patients undergoing total knee arthroplasty (TKA) has yielded mixed results. The PILLAR study, which was designed to minimize limitations associated with previous studies, compared the effects of LIA with or without LB on pain scores, opioid consumption, including proportion of opioid-free patients, time to first opioid rescue, and safety after primary unilateral TKA.

Concepts: Randomized controlled trial, Local anesthesia, Opioid, Pain, Cultural studies, Knee replacement, Mixed martial arts, The Pillar

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Currently available local anesthetics approved for single-injection peripheral nerve blocks have a maximum duration of <24 hours. A liposomal bupivacaine formulation (EXPAREL, Pacira Pharmaceuticals, Inc., San Diego, CA), releasing bupivacaine over 96 hours, recently gained Food and Drug Administration approval exclusively for wound infiltration but not peripheral nerve blocks.

Concepts: Pharmacology, Anesthesia, Local anesthesia, Local anesthetic, Peripheral nervous system, Block, Nerve block

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Abstract Objective. This study aimed to survey current Swedish practices for performing and handling transrectal ultrasound-guided prostate biopsies. Material and methods. A Swedish Urology Network (SUNe) was organized for the distribution of information, survey studies and research collaborations. A web-based questionnaire was distributed to the members in 2011. Results. In this first SUNe survey, 137 (91%) of the 151 members replied. All used antibiotic prophylaxis (84% ciprofloxacin, 12% trimethoprim-sulfamethoxazole), most commonly (63%) as a single dose of ciprofloxacin. Local anaesthesia was used by 87%. Half of the respondents only used a “side-fire” probe, whereas 17% always used an “end-fire” probe. Most (84%) routinely took 10 or more biopsy cores. About three-quarters started with the right base of the prostate and did not routinely take midline biopsies. More than one-third never or rarely sampled the anterior part of the prostate. There was great variability in how biopsy location was reported, but 71% considered a national standardized coordinate system desirable. Fine-needle aspiration was used occasionally by 39%, in more than 10% of cases by 6% and always by 2%. Most urologists mounted the biopsy cores on paper before fixation (78%), put only one core per jar (75%) and used flat-bottomed jars (70%). Conclusions. Most routines for handling of prostate biopsies, antibiotic prophylaxis, local anaesthesia and number of cores were uniform. However, there is still a need for standardization of the performance of ultrasound-guided biopsies. Although the method used to specify biopsy location varied greatly, most urologists would prefer a national standardized system.

Concepts: Biopsy, Pathology, Surgery, Prostate cancer, Local anesthesia, Medical tests, Needle aspiration biopsy, Benign prostatic hyperplasia

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BACKGROUND: Interscalene nerve blocks provide adequate analgesia, but there are no objective criteria for early assessment of correct catheter placement. In the present study, pulse oximetry technology was used to evaluate changes in the perfusion index (PI) in both blocked and unblocked arms, and changes in the plethysmographic variability index (PVI) were evaluated once mechanical ventilation was instituted. METHODS: The PI and PVI values were assessed using a Radical-7™ finger pulse oximetry device (Masimo Corp., Irvine, CA, USA) in both arms of 30 orthopedic patients who received an interscalene catheter at least 25 min before induction of general anesthesia. Data were evaluated at baseline, on application of local anesthetics; five, ten, and 15 min after onset of interscalene nerve blocks; after induction of general anesthesia; before and after a 500 mL colloid fluid challenge; and five minutes thereafter. RESULTS: In the 25 patients with successful blocks, the difference between the PI values in the blocked arm and the PI values in the contralateral arm increased within five minutes of the application of the local anesthetics (P < 0.05) and increased progressively until 15 min. After induction of general anesthesia, the PI increased in the unblocked arm while it remained relatively constant in the blocked arm, thus reducing the difference in the PI. A fluid challenge resulted in a decrease in PVI values in both arms. CONCLUSION: The perfusion index increases after successful interscalene nerve blockade and may be used as an indicator for successful block placement in awake patients. The PVI values before and after a fluid challenge can be useful to detect changes in preload, and this can be performed in both blocked and unblocked arms. (ClinicalTrials.gov number: NCT 01389011).

Concepts: Anesthesia, Local anesthesia, Catheter, Pulse oximetry, Local anesthetic, Block, Blocking, Masimo

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Achievement of asymmetry remains one of the goals of cosmetic procedures. Interestingly, scar asymmetry after abdominoplasty has been rarely considered a complication. However, this can have a significant impact on patient and surgeon satisfaction. This study identifies silent seromas as a potential cause of scar asymmetry.Among abdominoplasty procedures in a university hospital institution over a 30 months' period (October 1, 2007 to April 1, 2010), we retrospectively identified 6 patients who developed abdominal scar asymmetry only 3 months postoperatively and without any early warning complications (hematoma, seroma, or infection). Clinical examination was completed by abdominal diagnostic ultrasonography. Seroma capsulectomy under local anesthesia was performed in all cases.In all patients clinically presenting late abdominal scar asymmetry, ultrasonography confirmed the presence of an encapsulated chronic seroma. Surgical capsulectomy under local anesthesia resulted in reestablishment of former symmetry and high patient satisfaction. No complications such as wound infection, dehiscence, hematoma, or recurrence of seroma were detected after revision surgery.In our experience, fibrous capsule due to chronic seromas resulted in abdominal scar deviation and asymmetry. Surgical capsulectomy followed by wearing of compressive garments resulted to be an effective treatment with pleasant aesthetic outcome and no seroma recurrence. Silent seromas should be considered as a possible etiologic factor of scar asymmetries appearing during late follow-up after abdominoplasty.

Concepts: Hospital, Infection, Surgery, Physician, Anesthesia, Local anesthesia, Wound, 2007

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The use of local anesthesia with lidocaine containing epinephrine in patients with cardiac disease is controversial in the literature. The aim of our study was determining the safety of use the local anesthesia contain epinephrine in patients with ischemic heart disease that undergoing reconstructive surgery. Thirty two patients that had known ischemic heart disease and candidate to undergo reconstructive surgery for skin tumor enrolled in this study.  All patients continued their medication for cardiac disease till morning of the operation. 10 ml lidocaine 2% containing 1:100,000 epinephrine was injected in patients for local anesthesia. The hemodynamic changes and electrocardiographic variables before injection were compared with them after injection, during surgery and till 6 hours postoperation period. A 12 lead electrocardiogram was recorded in all our cases for detection of myocardial ischemic changes. The mean age, weight and height were 58.2±10.4, 74.8.±14.4 kg and 164.5± 8 cm respectively. Twelve patients (37.5%) were diagnosed with systemic hypertension and 10 patients with diabetes (31.2%). The comparison of change of systolic, diastolic and mean blood pressure between baseline, during procedure and after operation defined that our subjects did not have any significant disturbance in blood pressure in perioperative period. The comparison of baseline heart rate with heart rate after injection, during procedure and in postoperation period indicated a significant changes in this variable (P=0.044). The heart rhythm during the perioperative period also failed to exhibit alterations. The ischemic change was not recorded in our patients before injection compared to after injection. None of our patients have any early complications because of infiltration of local anesthetic containing epinephrine in our patients. The use of 10 ml 2% lidocaine with epinephrine 1:100,000 in patients with cardiac disease represent a safe anesthetic procedure. These patients experienced a more profound anesthesia with hemodynamic stability and without myocardial ischemic changes.

Concepts: Hypertension, Cardiology, Heart, Blood pressure, Heart disease, Anesthesia, Local anesthesia, Local anesthetic

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BACKGROUND: Historically, the anterolateral interscalene block-deposition of local anesthetic adjacent to the brachial plexus roots/trunks-has been used for surgical procedures involving the shoulder. The resulting block frequently failed to provide surgical anesthesia of the hand and forearm, even though the brachial plexus at this level included all of the axons of the upper-extremity terminal nerves. However, it remains unknown whether deposition of local anesthetic adjacent to the seventh cervical root or inferior trunk results in anesthesia of the hand and forearm. METHODS: Using ultrasound guidance and a needle-in-plane posterior approach, a Tuohy needle was positioned with the tip located between the deepest and next-deepest visualized brachial plexus root/trunk, followed by injection of mepivacaine (1.5%). Grip strength and the tolerance to cutaneous electrical current in 5 terminal nerve distributions were measured at baseline and then every 5 minutes following injection for a total of 30 minutes. The primary end point was the proportion of cases in which the interscalene nerve block resulted in a decrease in grip strength of at least 90% and hand and forearm anesthesia (tolerance to >50 mA of current in all 5 terminal nerve distributions) within 30 minutes. The primary hypothesis was that a single-injection interscalene brachial plexus block produces a similar rate of anesthesia of the hand and forearm to the published success rate of 95% for other brachial plexus block approaches. RESULTS: Of 55 subjects with blocks placed per protocol, all had a successful block of the shoulder as defined by inability to abduct at the shoulder joint. Thirty-three subjects had measurements at 30 minutes following local anesthetic deposition, and only 5 (15%) of these subjects had a surgical block of the hand and forearm (P < 0.0001; 95% confidence interval, 6%-33%). We therefore reject the hypothesis that the interscalene block as performed in this study provides equivalent anesthesia to the hand and forearm compared with other brachial plexus block techniques. Block failures of the hand and forearm were due to inadequate cutaneous anesthesia of the ulnar (n = 27; 82%), median (n = 26; 78%), or radial (n = 22; 67%) distributions; the medial forearm (n = 25; 76%); and/or the lateral forearm (n = 14; 42%). Failure to achieve at least a 90% reduction in grip strength occurred in 16 subjects (48%). CONCLUSIONS: This study did not find evidence to support the hypothesis that local anesthetic injected adjacent to the deepest brachial plexus roots/trunks reliably results in surgical anesthesia of the hand and forearm.

Concepts: Surgery, Anesthesia, Local anesthesia, Forearm, Ulnar nerve, Local anesthetic, Brachial plexus, Nerve block

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All previously documented regional anesthesia procedures for carotid artery surgery routinely require additional local infiltration or systemic supplementation with opioids to achieve satisfactory analgesia because of the complex innervation of the surgical site. Here, we report a reliable ultrasound-guided anesthesia method for carotid artery surgery. High-resolution ultrasound-guided regional anesthesia using a 12.5-MHz linear ultrasound transducer was performed in 34 patients undergoing carotid endarterectomy. Anesthesia consisted of perivascular regional anesthesia of the internal carotid artery and intermediate cervical plexus block. The internal carotid artery and the nerves of the superficial cervical plexus were identified, and a needle was placed dorsal to the internal carotid artery and directed cranially to the carotid bifurcation under ultrasound visualization. After careful aspiration, local anesthetic was spread around the internal carotid artery and the carotid bifurcation. In the second step, local anesthetic was injected below the sternocleidomastoid muscle along the previously identified nerves of the intermediate cervical plexus. The necessity for intra-operative supplementation and the conversion rate to general anesthesia were recorded. Ultrasonic visualization of the region of interest was possible in all cases. Needle direction was successful in all cases. Three to five milliliters of 0.5% ropivacaine produced satisfactory spread around the carotid bifurcation. For intermediate cervical plexus block, 10 to 20 mL of 0.5% ropivacaine produced sufficient intra-operative analgesia. Conversion to general anesthesia because of an incomplete block was not necessary. Five cases required additional local infiltration with 1% prilocaine (2-6 mL) by the surgeon. Visualization with high-resolution ultrasound yields safe and accurate performance of the block. Because of the low rate of intra-operative supplementation, we conclude that the described ultrasound-guided perivascular anesthesia technique is effective for carotid artery surgery.

Concepts: Anesthesia, Local anesthesia, Internal carotid artery, Common carotid artery, External carotid artery, Internal jugular vein, Local anesthetic, Cervical plexus

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Our aim was to analyse the amount of anxiety and fear felt before, immediately after, and one week after, dental extraction. We studied 70 patients (35 men and 35 women (mean (SD) age 43 (±10) years), who were listed for dental extraction under local anaesthesia in a private clinic that specialised in oral surgery. Patients were evaluated on 3 consecutive occasions: immediately preoperatively, immediately postoperatively, and 7 days later. Each patient’s anxiety was measured using Spielberger’s State-Trait Anxiety Inventory (Spanish version), the Modified Corah Dental Anxiety Scale (MDAS) and the Dental Fear Survey. There were significant differences in the STAI-Trait scale between before and 7 days after extraction (p=0.04), and in the MDAS between before and immediately after extraction (p=0.02), and between immediately after and 7 days after extraction (p=<0.001). The DFS also differed between before and immediately after extraction (p=0.002), and between immediately and 7 days after extraction (p<0.001). Dental anxiety immediately after tooth extraction may be influenced by operative techniques (type of anaesthesia, duration of operation, or position of tooth extracted), but anxiety at 7 days after extraction is not.

Concepts: Anxiety, Anesthesia, Local anesthesia, Endodontic therapy, Oral and maxillofacial surgery, Toothache, Dentistry procedures, Dental extraction