Peripheral Nerve Blocks (peripheral + nerve_block)

Distribution by Scientific Domains

Selected Abstracts

Peripheral Nerve Blocks of the Hand

Douglas Dillon
No abstract is available for this article. [source]

A review of pediatric regional anesthesia practice during a 17-year period in a single institution

Summary Background:, There is anecdotal evidence of changes in pediatric regional anesthesia (RA) practice. We performed a retrospective review of prospective data on pediatric RA over 17 years in our institution. Methods:, Data were collected from an electronic database for every anesthetic performed between 1989 and 2005. Type of RA, if any, and age of the patient were noted. Patients were divided into two groups: ,4 years (younger group) and 5 years or older (older group). Results:, A total of 51 408 anesthetics were performed; 23 609 (46%) in the younger group. A total of 10 929 RA were performed. In the younger group, RA increased from 9.5% to 27.6% (P < 0.001). Neuraxial blocks decreased from 100% to 59.7% of RA. Caudals decreased in the late 1990s from 70% to 22% of RA and epidurals have decreased from 22% to 11% of RA since 2002. Neonatal spinals were introduced in 1990 and now reach 30% of RA. Peripheral blocks have increased up to 37% of RA since 1994. In the older group, RA increased from 9.2% to 23.3% (P < 0.001), less than in the younger (P < 0.01). Neuraxial blocks have decreased from 97% to 24.9% of RA (P < 0.001), more obviously than in the younger group (P < 0.001). Peripheral blocks emerged in 1994, outnumbering neuraxial blocks as early as 1995 and now account for 75% of RA. This increase is significantly more pronounced than in the younger group (P < 0.001). In both groups, peripheral blocks were distributed among plexus blocks (30%) and compartment/peripheral nerve blocks (70%). In the last 5 years, a perineural catheter was placed in 12.9% of peripheral blocks to ensure continuous postoperative analgesia. Conclusions:, In our hospital, there has been a dramatic increase in RA, mainly from 1989 to 1995. The most remarkable events in the last decade were: (i) the change in practice from neuraxial to peripheral blocks and (ii) the emergence of continuous postoperative analgesia via perineural catheters. [source]

Continuous peripheral nerve block catheter tip adhesion in a rat model

C. C. Buckenmaier III
Background:, Continuous peripheral nerve block (CPNB) has been used effectively in combat casualties from Iraq and Afghanistan to provide surgical anesthesia and extended duration analgesia during evacuation and convalescence. Little information is available concerning catheter tip tissue reaction with prolonged use. Methods:, Forty-eight male Sprague-Dawley rats were assigned (12 per group) to one of four catheter tip designs provided by Arrow International: group A, 20-gauge catheter with three side-holes and a bullet-shaped tip; group B, 19-gauge StimuCathÔ catheter with coiled omni-port end with hemispherical distal tip; group C, 19-gauge catheter with single end-hole in conducting tip; group D, 19-gauge catheter with closed conducting tip with four side-holes. Following laparotomy, a randomly assigned catheter tip was sutured to the parietal peritoneal wall with the tip extending between experimental injuries created on the abdominal wall and cecum. After 7 days in situ, the catheter tips were removed from the adhesion mass using a force gauge, and the grams of force needed for removal were recorded. Results:, The mean force ± standard deviation values were 1.09 ± 1.21 g for group A, 21.20 ± 30.15 g for group B, 0.88 ± 1.47 g for group C and 1.60 ± 2.50 g for group D. The variation of each catheter group mean force compared with that of group B was significant (P < 0.05). There was no significant difference in adhesion force between groups A, C and D. Conclusions:, These results suggest that the manufactured design of a CPNB catheter tip can contribute to the adhesion of the tip in an intense inflammatory environment. This finding may have important clinical implications for CPNB catheters left in place for extended periods of time. [source]

Dextrose 5% in water: fluid medium for maintaining electrical stimulation of peripheral nerves during stimulating catheter placement

B. C. H. Tsui
It is well documented that a higher electrical current is required to elicit a motor response following a normal saline (NS) injection during the placement of stimulating catheters for peripheral nerve block. We present three cases of continuous brachial plexus catheter placement in which Dextrose 5% in water (D5W) was used to dilate the perineural space instead of NS. Three brachial plexus blocks (two interscalene and one axillary) were performed in three different patients for pain relief. In each case, an insulated needle was advanced towards the brachial plexus. A corresponding motor response was elicited with a current less than 0.5 mA after needle repositioning. A stimulating catheter was advanced with ease after 3,5 ml of D5W was injected to dilate the perineural space. A corresponding motor response was maintained when the current applied to the stimulating catheter was less than 0.5 mA. Local anesthetic was then injected and the motor response immediately ceased. All blocks were successful and provided excellent pain relief with the continuous infusion of local anesthetics. [source]

Addition of sodium bicarbonate to lidocaine decreases the duration of peripheral nerve block in rat. (Harvard Medical School, Boston, MA) Anesthesiology 2000;93:1045,1052.

PAIN PRACTICE, Issue 2 2001
Catherine J. Sinnott
This study evaluated the effect of adding sodium bicarbonate to lidocaine with and without epinephrine versus equivalent alkalinization by sodium hydroxide (NaOH) on onset, degree, and duration of peripheral nerve block. The study was broken up into two parts. Part I examined alkalinization by sodium bicarbonate versus NaOH to pH 7.8 on 0.5% lidocaine, with and without epinephrine prepared from crystalline salt. Part II examined 0.5% and 1.0% commercial lidocaine solutions, with and without epinephrine, either unalkalinized or alkalinized with sodium bicarbonate or NaOH. The study concluded that with 1% commercial lidocaine without epinephrine, sodium bicarbonate decreases the degree and duration of the block. However, in solutions with epinephrine, sodium bicarbonate hastens onset, without effecting degree or duration. Comment by Octavio Calvillo, M.D., Ph.D. There is evidence that adding sodium bicarbonate to lidocaine without epinephrine improves the quality of epidural block, whereas adding sodium bicarbonate to lidocaine with epinephrine does not. The addition of 8.4% sodium bicarbonate to 2% lidocaine without epinephrine was shown to decrease the onset time and enhance the depth of the epidural block. When bicarbonate was added to 2% lidocaine with epinephrine neither onset time nor depth of the epidural block was affected. Most investigators have used epidural block as their paradigm. The authors in this study used the sciatic nerve block of the rat. [source]

The effects of clonidine on ropivacaine 0.75% in axillary perivascular brachial plexus block

W. Erlacher
Introduction: The new long-acting local anesthetic ropivacaine is a chemical congener of bupivacaine and mepivacaine. The admixture of clonidine to local anesthetics in peripheral nerve block has been reported to result in a prolonged block. The aim of the present study was to evaluate the effects of clonidine added to ropivacaine on onset, duration and quality of brachial plexus block. Methods: Patients were randomly allocated into two groups. In group I brachial plexus was performed using 40 ml of ropivacaine 0.75% plus 1 ml of NaCL 0.9%, and in group II brachial plexus was performed using 40 ml of ropivacaine 0.75% plus 1 ml (0.150 mg) of clonidine. Onset of sensory and motor block of radial, ulnar, median and musculocutaneous nerve were recorded. Motor block was evaluated by quantification of muscle force, according to a rating scale from 6 (normal contraction force) to 0 (complete paralysis). Sensory block was evaluated by testing response to a pinprick in the associated innervation areas. Finally, the duration of the sensory block was registered. Data were expressed in mean±SD. For statistical analysis a Student t -test was used. A P -value of ,0.05 was considered as statistically significant. Results: The duration of blockade was without significant difference between the groups. Group I: 718±90 min; Group II: 727±117 min. There was no intergroup difference in sensory and motor onset or in quality of blockade. Conclusion: The addition of clonidine to ropivacaine 0.75% does not lead to any advantage of block of the brachial plexus when compared with pure ropivacaine 0.75%. [source]

Ultrasound-guided technique allowed early detection of intravascular injection during an infraclavicular brachial plexus block

The reported incidence of complications after peripheral nerve blocks is generally low and varies from 0% to 5%. The injuries related to brachial plexus block are perhaps more commonly reported, than after peripheral blocks of the lower extremity nerves. Recent reports suggest that expert ultrasound guidance may reduce but not completely eliminate complications as intraneural or intravascular injection. We report a case of accidental intravascular injection of local anesthetic during infraclavicular brachial plexus block, in spite of the use of ultrasound guidance technique, and negative aspiration for blood. [source]

Impact of a regional anesthesia rotation on ultrasonographic identification of anatomic structures by anesthesiology residents

Objective: The specific aim of this study was to determine the ability of anesthesiology residents to independently identify a series of anatomic structures in a live model using ultrasound, both before and after a 4-week regional anesthesia rotation that incorporates a standardized ultrasound training curriculum for peripheral nerve blockade. Methods: Ten CA2 and CA3 anesthesiology residents volunteered to participate in this study. Each resident was subjected to a pre-rotation practical exam, in which he attempted to identify 15 structures at four sites of peripheral nerve blockade, in a test subject. Each resident then received specific training for ultrasound-guided nerve blocks during a 4-week regional anesthesia rotation, and then completed a post-rotation exam. The mean number of structures correctly identified on the exams was compared for significant differences utilizing a paired t -test. Results: Residents were able to identify significantly more anatomic structures on the post-rotation exam as compared with the pre-rotation exam (mean 14.1 vs. 9.9, P<.001), as well as more peripheral nerve targets. The most frequently misidentified structures on the pre-rotation exam were the subclavian vein, the sciatic nerve in the popliteal fossa, and the femur. Conclusions: Ultrasound-naïve anesthesiology residents, who received instruction and experience with ultrasound-guided peripheral nerve blocks on a 4-week regional anesthesia rotation, significantly improved their ability to independently identify relevant anatomic structures with ultrasonography. [source]

Training in peripheral nerve blocks of the lower extremity should not be ignored

H. P. Lau
No abstract is available for this article. [source]

The successful use of peripheral nerve blocks for femoral amputation

We present a case report of four patients with severe cardiac insufficiency where peripheral nerve blocks guided by either nerve stimulation or ultrasonography were the sole anaesthetic for above-knee amputation. The patients were breathing spontaneously and remained haemodynamically stable during surgery. Thus, use of peripheral nerve blocks for femoral amputation in high-risk patients seems to be the technique of choice that can lower perioperative risk. [source]

Are peripheral and neuraxial blocks with ultrasound guidance more effective and safe in children?

Summary Background and aims:, The efficacy and safety of ultrasound guided (USG) pediatric peripheral nerve and neuraxial blocks in children have not been evaluated. In this review, we have looked at the success rate, efficacy and complications with USG peripheral nerve blocks and compared with nerve stimulation or anatomical landmark based techniques in children. Methods:, All suitable studies in MEDLINE, EMBASE Drugs and Cochrane Evidence Based Medicine Reviews: Cochrane Database of Systemic Reviews databases were identified. In addition, citation review and hand search of recent pediatric anesthesia and surgical journals were done. All three authors read all selected articles independently and a consensus was achieved. All randomized controlled trials (RCTs) comparing USG peripheral and neuraxial blocks with other techniques in children were included. Results:, Ultrasound guidance has been demonstrated to improve block characteristics in children including shorter block performance time, higher success rates, shorter onset time, longer block duration, less volume of local anesthetic agents and visibility of neuraxial structures. Conclusion:, Clinical studies in children suggest that US guidance has some advantages over more traditional nerve stimulation,based techniques for regional block. However, the advantage of US guidance on safety over traditional has not been adequately demonstrated in children except ilio-inguinal blocks. [source]

Great auricular nerve blockade using high resolution ultrasound: a volunteer study

ANAESTHESIA, Issue 8 2010
A. Thallaj
Summary This prospective, observational volunteer study aimed to describe the appearance of the great auricular nerve using ultrasound and its blockade under ultrasound guidance. An in-plane needle guidance technique was used for blockade of the great auricular nerve with 0.1 ml mepivacaine 1%. Sensory block was evaluated by pinprick testing in comparison with the contralateral area propriae. The great auricular nerve was successfully seen in all volunteers and the tail of the helix, antitragus, lobula and mandibular angle were blocked in all cases whereas the antihelix and concha were never blocked. Ultrasound imaging of the great auricular nerve can be reliably achieved and successful blockade with minimal volumes of local anaesthetic is another example of the benefits of ultrasound-guided peripheral nerve blocks. [source]

Litigation related to regional anaesthesia: an analysis of claims against the NHS in England 1995,2007,

ANAESTHESIA, Issue 5 2010
K. Szypula
Summary We analysed 366 claims related to regional anaesthesia and analgesia from the 841 anaesthesia-related claims handled by the National Health Service Litigation Authority between 1995 and 2007. The majority of claims (281/366, 77%) were closed at the time of analysis. The total cost of closed claims was £12 724 017 (34% of the cost of the anaesthesia dataset) with a median (IQR [range]) of £4772 (£0,28 907 [£0,2 070 092]). Approximately half of the claims (186/366; 51%) were related to obstetric anaesthesia and analgesia and of the non-obstetric claims, the majority (148/180; 82%) were related to neuraxial block. The total cost for obstetric closed claims was £5 433 920 (median (IQR [range]) £5678 (£0,27 690 [£0,1 597 565]) while that for non-obstetric closed claims was £7 290 097 (£3337 (£0,31 405 [£0,2 070 062]). Non-obstetric claims were more likely to relate to severe outcomes than obstetric ones. The maximum values of claims were higher for claims related to neuraxial blocks and eye blocks than for peripheral nerve blocks. Despite many limitations, including lack of clinical detail for each case, the dataset provides a useful overview of the extent, patterns and cost associated with the claims. [source]

Neurological complication analysis of 1000 ultrasound guided peripheral nerve blocks for elective orthopaedic surgery: a prospective study,

ANAESTHESIA, Issue 8 2009
M. J. Fredrickson
Summary Little data exists regarding the frequency of neurological complications following ultrasound guided peripheral nerve blockade. Therefore, we studied single injection and continuous ultrasound guided interscalene, supraclavicular, infraclavicular, femoral and sciatic nerve blocks in patients undergoing orthopaedic extremity surgery. All patients were contacted during postoperative weeks 2,4 and questioned for numbness or altered sensation anywhere in the involved extremity, and pain or weakness unrelated to surgery. The presumed aetiology of symptoms was based on the collective agreement of principal investigator, primary surgeon and a neurologist. Multivariate analysis was performed for characteristics potentially important in the causation of neurological complications. Of 1010 consecutive blocks, successful follow up between weeks 2 and 4 occurred in 98.6%. New, all-cause, neurological symptoms were present in 56/690 blocks (8.2%) at day 10, 37/1010 (3.7%) at 1 month and 6/1010 (0.6%) at 6 months. Most symptoms were due to causes unrelated to the block. Of 452 patients directly questioned at the time of the block, new neurological symptoms were more common in patients who experienced procedure-induced paraesthesia (odds ratio = 1.7, p = 0.029). The postoperative neurological symptom rate in this series is very similar to those previously reported following traditional techniques. [source]

Regional anaesthesia for limb surgery: a review of anaesthetists' beliefs and practice in the Oxford region*

ANAESTHESIA, Issue 6 2008
N. M. Feely
Summary We conducted a postal survey of 210 anaesthetists in the Oxford region to determine their views and practice regarding the timing of regional anaesthesia when combined with general anaesthesia for adults undergoing limb surgery and to compare the results with those obtained in a similar survey conducted in 2001. Of the 151 respondents (72% response rate), 102 (68%) regularly combined regional and general anaesthesia for adult limb surgery. Over 80% believed that central neuraxial blocks should be performed before general anaesthesia. This matched their current practice, marking a change from 2001. Significantly fewer anaesthetists believed it necessary to perform peripheral nerve blocks before general anaesthesia than in 2001, marking another significant change in practice. Overall, the results indicate an increased popularity of regional blocks in combination with general anaesthesia when compared with 2001 practice, which we believe is related to high quality advanced training modules now on offer to senior trainees in the Oxford region. [source]