Multiple Injection Technique Research Articles

Facial fillers: Relevant anatomy, injection techniques, and complications.

The aim of this review article is to discuss the currently available facial fillers, their differences and indications, relevant anatomy, injection techniques, and avoidance and management of complications. Clinical experience and scientific papers. Reversal of facial aging via filler injection has been around since the late 1800s with the initial use of detrimental products. Today, many safe and effective products exist and can be tailored to the individual patient's desired effect. With the evolution of both products and injection techniques, the rate of complications with facial filler use is low. Nonetheless, providers offering facial filler injections should have detailed knowledge of facial anatomy, including facial planes and soft tissue compartments. Multiple injection techniques exist. Different techniques should be used, depending on the anatomic target. Providers should also know how to avoid and manage complications.

(402) Analysis of Peyronie’s Disease Injection Techniques

Abstract Introduction Collagenase clostridium histolyticum (CCH) is the only food and drug administration (FDA) approved intralesional medication for Peyronies Disease (PD). The manufacture instructions recommend a single injection into the plaque at the point of maximal curvature. However, a 2019 survey of the Sexual Medicine Society of North America (SMSNA) found that physicians were utilizing many different injection techniques. It is unknown if one technique is superior. Objective To assess delivery of medication into PD plaques using an invitro model. Methods We obtained PD plaques from men undergoing plaque excision and grafting. Plaques were stored at -80C until ready for use in the lab. We injected the plaques with 0.25ml of Eosin Y, 5 wt. 5% solution in water because this solution is visibly red and similar to the density of CCH. We assess how the dye spread through the plaque in four different injection techniques: single injection, single injection with slow pull back, multiple site injection and lateral injection. All injections were video recorded in real time. Results Dye was retained inside the plaques will all injection techniques, however in all conditions, a significant amount of dye leaked out of the plaques. Multiple injection technique appeared to have the least about of dye leak out of the plaque. Conclusions In all conditions, dye leaked out of the plaques, however the multiple injection technique appears to have deliver the greatest amount Disclosure Any of the authors act as a consultant, employee or shareholder of an industry for: Endo Pharmaceuticals

Comparison of Free Diced and Multiple Toothpick-Shaped Costal Cartilage Injection Techniques for Augmentation Rhinoplasty.

The free diced costal cartilage (FDCC) injection technique has been used in the augmentation rhinoplasty for a long time. In order to lower the incidence of nasal contour irregularities and graft displacement, we developed the multiple toothpick-shaped costal cartilage (MTCC) injection technique. This comparative study was conducted to introduce and assess this new technique. This retrospective analysis included 51 patients who underwent augmentation rhinoplasty with either the FDCC or MTCC injection technique at the 17th Department of Plastic Surgery in the Plastic Surgery Hospital between July 2014 and May 2020. The patients were divided into the FDCC (n = 30, 58.82%) and MTCC (n = 21, 41.18%) groups. General data, postoperative patient satisfaction, complications and revision rate were compared between the groups. Except for the follow-up period, there were no significant differences in general data (age, sex, preoperative dorsum deformity, preoperative rhinoplasty history) between the groups. Postoperative patient satisfaction, complications and revision rate were similar between the two groups. The MTCC injection is a safe and effective technique for augmentation rhinoplasty. Like the FDCC injection technique, the new technique is relatively easy to perform and time-saving with concealed scarring and minimal postoperative edema. Most of its revision surgeries are also easy to perform by simple rasping and reinjection. According to our experience, the new technique may have wider indication as well as lower incidence of nasal contour irregularities and graft displacement. Therefore, we suggest that the MTCC injection technique is reliable and worthy of recommendation. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Experimental study on the evolution of pore-fracture structures and mechanism of permeability enhancement in coal under cyclic thermal shock

Heat injection is a new method of recovering enhanced coalbed methane (ECBM). In this study, the impact of a sudden increase in ambient temperature on the permeability of coal was studied, and the application prospects of multiple thermal effects in coal fracturing and permeability enhancement were explored. The permeability and development of pore-fracture structures in coal were tested before and after cyclic thermal shock. The evolution characteristics of the pore distribution were evaluated, and an empirical formula for estimating the permeability growth of coal was established. Digital image processing technology and fractal theory were used to analyse changes in macroscopic fractures. The results indicates that cyclic thermal shock could effectively promote the generation and expansion of permeability pores, effectively connect the relatively independent fracture structures, and break and expand the microfractures and pore groups to form an interwoven fracture network. The increase in cyclic thermal shock resulted in an increase of 0.92%, 1.13%, and 16.15% in total porosity increment, the porosity increment of seepage pores and the proportion increment of seepage pores, respectively, after seven thermal shocks. The permeability of coal exhibited a logarithmic growth pattern with an increase in the number of thermal shock cycles; the average permeability increased by 100.02% after seven cycles. Based on the theory of thermodynamics, the influencing mechanism of cyclic thermal shock on the evolution of pore-fracture structures was explored. Differences were observed in the thermal expansion coefficients of minerals in coal, and thermal stress was generated under cyclic thermal shock, which may lead to damage, promoting fracture formation and increasing permeability. With an increase in the number of thermal shock cycles, the efficiency of permeability enhancement gradually decreased, which suggests that the reservoir conditions should be combined and mining plan should be reasonably set in ECBM extraction using multiple thermal injection techniques.

Identification of complications and side effects with axillary approach to the brachial plexus block while using lignocaine hydro chloride: A clinical study

The axillary approach to brachial plexus blockade provides satisfactory anaesthesia for elbow, forearm, and hand surgeries also provides reliable cutaneous anaesthesia of the inner aspect of the upper arm including the medial cutaneous nerve of arm and intercostobrachial nerve, areas often missed with other approaches. In addition, the axillary approach remains the safest of all the other approaches as it does not risk blockade of the phrenic nerve, nor does it have the potential to cause pneumothorax, making it an ideal approach for day care surgery. Historically, single-injection techniques have not provided reliable blockade in the musculocutaneous and radial nerve territories, but success rates have greatly improved with multiple-injection techniques whether using nerve stimulation or ultrasound guidance. The present study has been undertaken to evaluate the complications and side effects during axillary approach to brachial plexus. The study was conducted on 50 patients of age between 15 to 65 years of either sex (using 1.5% lignocaine hydrochloride with epinephrine. one patient developed restlessness and two cases of accidental puncture of axillary artery occurred during performance of the procedure. The procedure was repeated after applying firm pressure over the artery for 5 minutes. Quality was excellent in 48% (n=24), Good in 44% (n=22), Fair 4% (n=2) and Poor/Failure in 4% (n-=2).

Treating the Lips and Its Anatomical Correlate in Respect to Vascular Compromise.

Treating the lips to increase facial attractiveness and youthfulness is challenging when trying to consider ethnic differences in an increasingly more diverse society. Multiple injection techniques are currently available for treating lip contour and volume, but a validation in the cadaveric model under the aspects of safety has not been performed yet. The injection techniques presented in this study are based on the experience and personal selection of the authors. The authors have assessed, treated, and evaluated for more than 20 years patients from the Middle East and Central Europe. Cadaveric verification was performed for each of the presented techniques to identify the positioning of the injected product inside the lips and its relation to the superior/inferior labial arteries. The results of the anatomic analyses revealed that in 58.3% of the performed injections, the product was placed close to the superior/inferior labial arteries. In 60.0% of the cases, applications using a needle placed the injected product in endangered locations, whereas 57.1% of the cases using cannulas placed the product in endangered locations (i.e., in the vicinity of the superior/inferior labial arteries). This anatomic study revealed that injected material into the lips is frequently placed in close proximity to labial arteries representing a high risk for intra-arterial applications, leading to tissue loss (necrosis) and potential end-arterial embolism (potential blindness). Nevertheless, treatment of the lips should be a multistep approach focusing first on the far (upper and middle face) and close (labiomandibular and labiomental) perioral regions.

The estimation of minimum effective volume of 0.5% ropivacaine in ultrasound-guided interscalene brachial plexus nerve block: A clinical trial.

Background and Aims:Interscalene brachial plexus block (ISB) is the most commonly used mode of anesthesia for upper limb surgeries. Higher volume of local anesthetic used in ISB is associated with increased incidence of side effects, particularly phrenic nerve palsy. The aim of this study was to determine the minimum effective volume of 0.5% ropivacaine in 90% patients (MEV90) in ISB.Material and Methods:With target of 45 successful cases, phase 1 clinical trial was conducted based on the principles of biased coin design up-and-down method. After obtaining Ethical Committee's approval and patient's consent, patients with American Society of Anesthesiologist physical status (ASA PS) I and II, aged 18–60 years of either sex, undergoing upper arm surgery were recruited into the study until 45 successful cases. A 7 ml of 0.5% ropivacaine was used as starting dose, with patients receiving a higher or lower dose depending on previous patient's response. R package, SPSS 23, and Microsoft Excel were used for statistical analysis.Results:MEV90 of 0.5% ropivacaine for ISB was determined as 8.64 ml [confidence interval (CI) 95%, 8.28–9.02 ml]. Time for onset of sensory block and motor block was 5 min (5–15 min) and 10 min (5–20 min), respectively, while duration of analgesia was observed as 8.2 (4.8–12.5) h.Conclusions:This study observes that surgical anesthesia can be accomplished with 8.64 ml (95% CI: 8.28–9.02 ml) of 0.5% ropivacaine with ultrasound-guided ISB with multiple injection technique, without clinical deterioration in block onset and duration of analgesia.

Fascial layers influence the spread of injectate during ultrasound-guided infraclavicular brachial plexus block: a cadaver study

Fascial layers of the neurovascular sheath containing the brachial plexus influence distribution of local anaesthetic, hence increasing the risk of block failure when performing infraclavicular brachial plexus block (ICB). Ultrasound-guided infraclavicular brachial plexus block was performed on cadavers using a single injection technique with dye (20-30 ml). After injection, we carried out consecutive dissection of the neurovascular bundle to study dye injectate spread and identify the presence of fascial layers. Ultrasound video images (scout scan and injection) and recordings of dissections were evaluated by independent experts (regional anaesthetists and anatomists). Well defined fascial layers were identified at dissection in seven out of 12 infraclavicular spaces studied. These fascial layers impeded the spread of dye injectate substantially in six cases and partially in one case. No fascial layers were identified at dissection in five cases, in each of which the spread of injectate was complete throughout the neurovascular bundle. The sensitivity and specificity of ultrasonography and haptic sensation for detection of fascial layers were poor. When fascial layers are present in the neurovascular sheath, they impede the spread of injectate during infraclavicular brachial plexus block. Ultrasound detection of these fascial layers is unreliable in cadavers. These findings support the use of greater volumes of injectate or a multiple injection technique when performing this block.

Ultrasound Guidance Versus Peripheral Neurostimulation for Brachial Plexus Block Anesthesia with Axillary Approach and Multiple Injection Technique

Abstract Introduction: There are several approaches for brachial plexus anesthesia: supraclavicular, infraclavicular, interscalenic and axillary. Out of these, the axillary approach is considered to be the safest because of the low risk of lesioning the adjacent structures, low risk of phrenic nerve blockade or of producing an iatrogenic pneumothorax. The block can be performed by one single injection at the site, by two injections or by several injection, among each nerve of the plexus. Ultrasound was introduced in regional anesthesia since 1978, being used initially as an auxiliary method to peripheral neurostimulator. Objectives: The evaluation of ultrasound efficiency as an auxiliary method for brachial plexus block performance, in terms of success rate, vascular punctures. The influence of obesity on performing time, total duration of the block, and success rate of brachial plexus block. Material and method: Prospective, randomized study which enrolled adult patients, scheduled for surgical emergency or elective surgical intervention on upper limb with brachial plexus block by axillary approach, using either the peripheral nerve stimulation or the ultrasound guidance. Results: We enrolled 160 patients, grouped in two sets- the ultrasound group= 82 patients (US) the neurostimulation group = 78 patients (NS). Vascular punctures were statistically significant different p= 0, 04. The success rate was not influenced by the obesity. Conclusions: Ultrasound guidance makes axillary brachial plexus block safer, we can recommend ultrasound guidance as routine for axillary brachial plexus block. The obese patient can beneficiate by both methods of brachial plexus blockage.

Minimum Effective Volume of Lidocaine for Ultrasound-Guided Costoclavicular Block

This dose-finding study aimed to determine the minimum effective volume in 90% of patients (MEV90) of lidocaine 1.5% with epinephrine 5 μg/mL for ultrasound-guided costoclavicular block. Using an in-plane technique and a lateral-to-medial direction, the block needle was positioned in the middle of the 3 cords of the brachial plexus in the costoclavicular space. The entire volume of lidocaine was deposited in this location. Dose assignment was carried out using a biased-coin-design up-and-down sequential method, where the total volume of local anesthetic administered to each patient depended on the response of the previous one. In case of failure, the next subject received a higher volume (defined as the previous volume with an increment of 2.5 mL). If the previous patient had a successful block, the next subject was randomized to a lower volume (defined as the previous volume with a decrement of 2.5 mL), with a probability of b = 0.11, or the same volume, with a probability of 1 - b = 0.89. Success was defined, at 30 minutes, as a minimal score of 14 of 16 points using a sensorimotor composite scale. Patients undergoing surgery of the elbow, forearm, wrist, or hand were prospectively enrolled until 45 successful blocks were obtained. This clinical trial was registered with ClinicalTrials.gov (ID NCT02932670). Fifty-seven patients were included in the study. Using isotonic regression and bootstrap confidence interval, the MEV90 for ultrasound-guided costoclavicular block was estimated to be 34.0 mL (95% confidence interval, 33.4-34.4 mL). All patients with a minimal composite score of 14 points at 30 minutes achieved surgical anesthesia intraoperatively. For ultrasound-guided costoclavicular block, the MEV90 of lidocaine 1.5% with epinephrine 5 μg/mL is 34 mL. Further dose-finding studies are required for other concentrations of lidocaine, other local anesthetic agents, and multiple-injection techniques.

Ultrasound-guided subcostal oblique transversus abdominis plane block in canine cadavers

ObjectivesTo describe the ultrasound-guided transversus abdominis plane (TAP) block using a subcostal oblique approach in dog cadavers and to evaluate the spread of a methylene blue solution using a multiple-injection technique. Study designProspective, descriptive, experimental anatomic study. AnimalsNine adult Beagle cadavers weighing a mean ± standard deviation of 13 ± 2 kg. MethodsMethylene blue solution (10.0 mL) was injected bilaterally within the fascia that overlies the transversus abdominis muscle in dog cadavers under ultrasound guidance. A total of three injections (3.3 mL each) were administered on each side by the same operator. Dissection was performed by a second operator 20 minutes later. Successful nerve staining was defined as the presence of dye on the nerve for a length of >1 cm. ResultsVentral branches of the T9, T10, T11, T12 and T13 nerves innervating the cranial abdominal wall were stained in 72%, 95%, 100%, 95% and 61% of cases, respectively. Ventral branches of L1 and L2 innervating the caudal abdominal wall were stained in only 33% and 11% of cases, respectively. The dye was found only in the fascia between the transversus abdominis and the internal oblique muscles. Conclusions and clinical relevanceThe ultrasound-guided subcostal oblique TAP block provided adequate staining of the sensory innervation of the cranial abdominal wall. Further studies are required to evaluate the efficacy of this technique in blocking the nociceptive response in clinical procedures.

Single, double or multiple-injection techniques for non-ultrasound guided axillary brachial plexus block in adults undergoing surgery of the lower arm.

Regional anaesthesia comprising axillary block of the brachial plexus is a common anaesthetic technique for distal upper limb surgery. This is an update of a review first published in 2006 and previously updated in 2011 and 2013. To compare the relative effects (benefits and harms) of three injection techniques (single, double and multiple) of axillary block of the brachial plexus for distal upper extremity surgery. We considered these effects primarily in terms of anaesthetic effectiveness; the complication rate (neurological and vascular); and pain and discomfort caused by performance of the block. We searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2016, Issue 3), MEDLINE (1946 to April Week 1 2016), Embase (1947 to April 18 2016) and reference lists of trials. We contacted trial authors. The date of the last search was April 2016 (updated from March 2013). We included randomized controlled trials that compared double with single-injection techniques, multiple with single-injection techniques, or multiple with double-injection techniques for axillary block in adults undergoing surgery of the distal upper limb. We excluded trials using ultrasound-guided techniques. Independent study selection, 'Risk of bias' assessment and data extraction were performed by at least two investigators. We undertook meta-analysis. We included one new trial involving 45 participants in this updated review. In total we included 22 trials involving a total of 2193 participants who received regional anaesthesia for hand, wrist, forearm or elbow surgery. 'Risk of bias' assessment indicated that trial design and conduct were generally adequate; the most common areas of weakness were in blinding and allocation concealment.Nine trials comparing double versus single injections showed a statistically significant decrease in primary anaesthesia failure (risk ratio (RR) 0.55, 95% confidence interval (CI) 0.34 to 0.89, high-quality evidence). Subgroup analysis by method of nerve location showed that the effect size was greater when neurostimulation was used rather than the transarterial technique.Nine trials comparing multiple with single injections showed a statistically significant decrease in primary anaesthesia failure (RR 0.25, 95% CI 0.14 to 0.42, high-quality evidence). Pooled data from five trials also showed a significant decrease in incomplete motor block (RR 0.61, 95% CI 0.39 to 0.96, high-quality evidence) in the multiple-injection group.Twelve trials comparing multiple versus double injections showed a statistically significant decrease in primary anaesthesia failure (RR 0.27, 95% CI 0.19 to 0.39, high-quality evidence). Pooled data from six trials also showed a significant decrease in incomplete motor block (RR 0.55, 95% CI 0.36 to 0.85, high-quality evidence) in the multiple injection group.Tourniquet pain was significantly reduced with multiple injections compared with double injections (RR 0.53, 95% CI 0.33 to 0.84, high-quality evidence). Otherwise there were no statistically significant differences between groups in any of the three comparisons on secondary analgesia failure, complications and patient discomfort. Compared with multiple injections, the time for block performance was significantly shorter for single injection (MD 3.33 minutes, 95% CI 2.76 to 3.90) and double injections (MD 1.54 minutes, 95% CI 0.80 to 2.29); however there was no difference in time to readiness for surgery. This review provides evidence that multiple-injection techniques using nerve stimulation for axillary plexus block produce more effective anaesthesia than either double or single-injection techniques. However, there was insufficient evidence to draw any definitive conclusions regarding differences in other outcomes, including safety.

Multiple-injection high-throughput gas chromatography analysis.

Multiple-injection techniques have been shown to be a simple way to perform high-throughput analysis where the entire experiment resides in a single chromatogram, simplifying the data analysis and interpretation. In this study, multiple-injection techniques are applied to gas chromatography with flame ionization detection and mass detection to significantly increase sample throughput. The unique issues of implementing a traditional "Fast" injection mode of multiple-injection techniques with gas chromatography and mass spectrometry are discussed. Stacked injections are also discussed as means to increase the throughput of longer methods where mass detection is unable to distinguish between analytes of the same mass and longer retentions are required to resolve components of interest. Multiple-injection techniques are shown to increase instrument throughput by up to 70% and to simplify data analysis, allowing hits in multiple parallel experiments to be identified easily.

The relationship of the musculocutaneous nerve to the brachial plexus evaluated by MRI

Axillary plexus blocks (AXB) are widely used for upper limb operations. It is recommend that AXB should be performed using a multiple injection technique. Information about the course and position of the musculocutaneous nerve (MCN) is of relevance for AXB performance. The objective of this study was to examine the position of the MCN and its relationship to the axillary sheath using MRI. 54 patients underwent an AXB with 40 ml of local anaesthetic before MRI examination. The course of the MCN and the position where it left the axillary sheath and perforated the coracobrachial muscle (MCN exit point), in relation to the axillary artery and the block needle insertion point in the axillary fold, were recorded. The MCN was seen clearly in 23, partly in 26, and not identified in five patients at the MCN exit point. The mean distance from the insertion point of the block needle in the axillary fold to the MCN exit point was 36.8 mm (SD = 18.9, range: 0–90.5). In 37 patients the MCN exit point was positioned inside the Q1 quadrant (lateral anterior to the axillary artery) and in 11 patients inside the Q2 quadrant (medial anterior to the axillary artery). There is a wide variability as to where the musculocutaneous nerve (MCN) leaves the axillary sheath. Therefore multiple injection techniques, or the use of a proximally directed catheter, should be appropriate to block the MCN.

Myasthenia gravis: A challenge

Sir, Most reports of patients with myasthenia gravis undergoing surgery are for thymectomy which is a treatment option in patients unresponsive to medical management.[1] There are few reports of patients with myasthenia posted for incidental surgery. We would like to report one such case where the patient was scheduled to undergo a modified radical mastectomy for carcinoma of the breast. A 40-year-old female (50 kg) diagnosed as a case of myasthenia gravis Grade II B since 1 year was scheduled for a mastectomy procedure. She had developed symptoms of dysphagia and dysarthria one year before. On further evaluation, it was diagnosed as myasthenia. She was started on pyridostigmine and steroid (since she did not improve only with pyridostigmine), to which she responded. She was also diabetic (due to steroid therapy) controlled on insulin. Her blood and other investigations were within normal range. Her pulmonary function tests (PFT) showed a decrease in vital capacity (2 L). Other parameters were normal. Since she was at risk of post-operative respiratory complications[1], we decided to avoid general anaesthesia. Among the various options paravertebral block (PVB),[2] thoracic epidural[3] block, and tumescent anaesthesia[4] (block) were considered. Tumescent anaesthesia involves the use of large volumes of local anaesthetic drugs, and was hence avoided. Thoracic epidural block[3,5] with a higher concentration of local anaesthetic may produce motor blockade and decrease vital capacity, forced expiratory volume and total lung capacity which was potentially dangerous in our patient due to bulbar muscle involvement. Hence, a PVB was decided to be administered. After patient consent and premedication with midazolam (1 mg) and fentanyl (70 μg), PVB was performed between T1 to T6 levels. 4cc of 0.25% bupivacaine with adrenaline was injected at each space. Sensory block was assessed over the respective dermatomes, and the surgery was continued with top ups of sedation and opioid analgesia (fentanyl 30 μg and dexmedetomidine 20 μg). Propofol (50 mg) was administered during the axillary clearance. Surgery lasted 90 min. The patient remained comfortable during the procedure. Analgesia lasted for 6 h post-operatively. She was restarted on oral dose of pyridostigmine soon after the procedure. She was discharged on the 3rd post-operative day. In patients with myasthenia, the parameters which indicate the need for post-operative mechanical ventilation include disease duration[1,6] >6 years, associated lung disease, pyridostigmine dose requirement >750 mg/day and vital capacity <2.9 L. Hence, a pre-operative lung function assessment is of utmost importance. Since the patient had dysphagia, possibility of aspiration is higher. A previous meta-analysis performed showed that PVB combined with general anaesthesia provided better post-operative analgesia[3,5] during breast surgery. Lesser incidence of adverse effects was reported with the use of PVB.[2,5] Since acute post-operative pain is a risk factor for the development of post-operative chronic pain[2,5], use of PVB is useful. PVB has also been shown to provide better analgesia than wound infiltration. PVB also provides better post-operative dynamic analgesia. Single level and catheter technique have been described, but we used the multiple injection technique. We conclude that regional anaesthesia, especially PVB is a feasible alternative in patients with myasthenia gravis undergoing modified radical mastectomy.

Guidance of axillary multiple injection technique for plexus anesthesia. Ultrasound versus nerve stimulation

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. 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. A total of 60 patients were randomized to either the SONO (n = 30) or STIM (n = 30) group. For the block 40-50ml mepivacaine 1.5 % (plexus) and 5-10ml 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). No differences were observed between the groups in terms of onset time (single nerves 10-20min, plexus 20-25min) and success rate (SONO 90 %, STIM 89 %). Patient satisfaction as measured by block-related pain score (VAS 2cm), 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 ± 1.72min vs. 8.05 ± 2.58, p = 0.02). Nerve stimulation-guided axillary plexus blocks performed by trained anesthesiologists may result in similar onset times and success rates compared to ultrasound-guided blocks.

Zastosowanie ultrasonografii w anestezji regionalnej znacząco zmienia praktykę kliniczną blokad obwodowych

Ultrasound-guided (US-guided) regional anaesthesia has gained worldwide popularity in recent years owing to the benefits the method offers to patients. The 1st Department of Anaesthesiology and Intensive Care of Warsaw Medical University was one of the first centres in Poland to employ US-guided peripheral nerve blocks (PNB) on a routine basis. The technique was incorporated into the institution's clinical practice from 2007. The purpose of this study was to retrospectively assess changes in the clinical practice of US-guided versus non US-guided PNBs over six years of experience with the technique. Retrospective analysis assessing the prevalence of PNB methods, local anaesthetic (LA) injection techniques (i.e. single injection vs. multiple), LA volumes used, success rates and the incidence of complications. This study included 4,066 PNBs performed between January 2006 and June 2012. The results showed systematic growth in the prevalence of US-guided blocks in the total number of PNBs, from 8.6% in 2007 up to 53.3% in 2012. The mean LA volume used in PNB was significantly lower in US-guided blocks compared to traditional PNB techniques (respectively, 21.83 mL vs. 31.41 mL, P < 0.05) without a decrease in the success rate (respectively, 76% vs. 74%, P > 0.05). A shift in the prevailing block technique from single injection to multiple injections was observed, regardless of the nerve location technique employed (from 29% up to 84% of PNBs performed using multiple injection technique). The use of ultrasound optimizes the technique of peripheral blocks and the amount of local anaesthetic used. Ultrasonography does not affect the safety of peripheral blocks.

Comparison of peripheral nerve stimulator versus ultrasonography guided axillary block using multiple injection technique.

Background:The established methods of nerve location were based on either proper motor response on nerve stimulation (NS) or ultrasound guidance. In this prospective, randomised, observer-blinded study, we compared ultrasound guidance with NS for axillary brachial plexus block using 0.5% bupivacaine with the multiple injection techniques.Methods:A total of 120 patients receiving axillary brachial plexus block with 0.5% bupivacaine, using a multiple injection technique, were randomly allocated to receive either NS (group NS, n = 60), or ultrasound guidance (group US, n = 60) for nerve location. A blinded observer recorded the onset of sensory and motor blocks, skin punctures, needle redirections, procedure-related pain and patient satisfaction.Results:The median (range) number of skin punctures were 2 (2–4) in group US and 3 (2–5) in group NS (P < 0.001). No differences were observed in the onset of sensory block in group NS (6.17 ± 1.22 min) and in group US (6.33 ± 0.48 min) (P = 0.16), and in onset of motor block (23.33 ± 1.26 min) in group US and (23.17 ± 1.79 min) in group NS; P > =0.27). Insufficient block was observed in three patient (5%) of group US and four patients (6.67%) of group NS (P > =0.35). Patient acceptance was similarly good in the two groups.Conclusion:Multiple injection axillary blocks with ultrasound guidance provided similar success rates and comparable incidence of complications as compared with NS guidance with 20 ml 0.5% bupivacaine.

Lateral Trendelenburg with the injected side down after the block improves the efficacy of the axillary approach to brachial plexus block

We hypothesized that, after axillary block, positioning the patient in a lateral position with the injected side down and simultaneously in a 20° Trendelenburg position will increase the success rate and quality of the block. Fifty patients with chronic renal failure (ASA 2-3) scheduled for arteriovenous fistula surgery were included in this study. In all patients, 30-40 ml of 0.25 % levobupivacaine were injected into the axillary sheath. The block was performed as three injections (multiple injection technique) with the arm in 90° abduction and 90° flexion in the supine position. Patients were randomly allocated to two groups. Group I (n = 25) patients were kept in the supine position after the block. Group II (n = 25) patients were positioned laterally after the block with the injected arm down and in a 20° Trendelenburg position. Sensory and motor block were evaluated at 2, 4, 6, 8, 10, 15, 20, and 25 min after the administration of the block. Thus, the patients in group II were evaluated in a lateral position during the first 30 min. Throughout the surgery and the recovery period, sensory and motor block were evaluated at 30-min intervals. There were no significant intergroup differences in the effects on radial, ulnar, median, and musculoskeletal nerve blockade. Thirty minutes after the injection, the patients in group II had higher levels of sensory axillary nerve blockade. Subscapular and thoracodorsal nerve motor block were not detected in group I, while 84 % of the patients in group II experienced blockade of both of these nerves (p < 0.01). We conclude that, for patients undergoing an axillary block, positioning the patient laterally with the injected side down and in a 20° Trendelenburg position increases the success rate and quality of the block.

Isolation of monoclonal antibody from a Chinese hamster ovary supernatant. II: Dynamics of the integrated separation on ion exchange and hydrophobic interaction chromatography media

Dynamics of the purification process of a CHO derived monoclonal antibody by ion exchange chromatography (IEC), hydrophobic interaction chromatography (HIC) and their integration has been investigated. To quantify the adsorption behavior of the target protein (IgG1) and impurities contained in the supernatant, their elution course on IEC and HIC columns has been analyzed versus pH and/or the salt concentration in the mobile phase. A short-cut method has been proposed for mathematical modeling and determining underlying kinetic and thermodynamic parameters. The accuracy of the model predictions has been verified by comparing the simulated and experimental band profiles recorded in both chromatographic processes. After verification, the model was used to optimize operating conditions for the column loading and chromatographic elution in the integrated process IEC/HIC. Two alternative loading techniques based on the upstream and downstream feed dilution were taken into account in the optimization routine. In the first one the feed stream was diluted with the loading buffer prior to the column loading, while in the latter one the feed dilution was realized inside the column using the multiple-injection technique. It was shown that the downstream dilution allowed significant reduction of the contact time between the protein and the loading buffer.