Pharmacological optimisation of ultrasound guided axillary brachial plexus block

Regional anaesthesia provide significant advantages in the perioperative care of the patient undergoing surgery, including improved postoperative analgesia, a reduction in adverse events, shorter recovery time, and expedited hospital discharge when compared to general anaesthesia. Safe performance of brachial plexus block warrants consideration of several factors, such as ⅰ. an understanding of relevant anatomy, ⅱ. effectiveness and potential adverse effects of brachial plexus approach for the intended site of surgery, ⅲ. methods of nerve localisation, and ⅳ. selection of pharmacological agents to enhance the quality of block. The choice of local anaesthetics in peripheral nerve block is dependent upon variables such as the desired onset and duration of motor and sensory nerve block, the expected duration of surgery and the requirement for post-surgical regional analgesia. Other factors that can modify the effectiveness of peripheral nerve blockade are the volume and concentration (and dose) of local anaesthetic injected and addition of adjuvants. The objective of this thesis is to evaluate the effect of local anaesthetic volumes, volume/concentration ratio (dose) and addition of adjuvants with a aim to optimise the clinical characteristics of the ultrasound-guided axillary brachial plexus block (USgABPB) for upper limb trauma surgeries. In the first study, we investigated the effect of two volumes (10 vs 30 mL) of lidocaine with epinephrine 1:200 000 on USgABPB. In the second study, we examined whether two different volumes and concentrations of a fixed dose of lidocaine with epinephrine by dilution influenced the characteristics of USgABPB. In the third study, we evaluated the effects of adding clonidine 1 µg/kg to 20 mL of lidocaine 2% with epinephrine 1:200 000 on the onset and duration of sensory and motor block following USgABPB. Our results added the following to the optimisation of the characteristics of the ultrasound guided axillary brachial plexus block. ⅰ. Higher volume (30mL compared to 10 mL) of lidocaine 2% with epinephrine resulted in longer overall duration of sensory and motor block and a shorter sensory and motor block onset time. ⅱ. Dilution of a fixed dose of lidocaine with epinephrine administered as 40 mL of lidocaine 1% (when compared to 20 mL of lidocaine 2%) with epinephrine resulted in faster overall onset of block. ⅲ. Admixture of clonidine 1µg/kg to lidocaine with epinephrine for ultrasound guided axillary brachial plexus block resulted in faster onset and longer duration of both sensory and motor block with extended duration of postoperative analgesia. On the contrary, the duration of lower volume group was similar when compared with the duration of block from our other studies (20 ml of lidocaine 2% with epinephrine 1:200,000). It seems that the relation between volume (dose) and duration of the block is not linear and any increase beyond the threshold volume, improvements in the block characteristics becomes less significant. Our findings indicate an optimal approach may comprise low (dose) volume (10 ml of Lidocaine 2% with epinephrine 1:200, 000) with adjuvant (clonidine 1µg/kg) to enhance the characteristics of USgABPB for patients undergoing upper extremity trauma surgeries. Our research findings also indicates that, dilution of this admixture to a greater volume can be utilised to improve the onset of the brachial plexus block and operator performance characteristics. In addition to this following original body of work a review article was published on Ultrasound guided axillary brachial plexus block

Enantioselective synthesis of bronchodilating agent (R)-Salmeterol^#

1347-1352Synthesis of β2-adrenoreceptor agonist bronchodilator (R)-Salmeterol has been described with good yields. The synthesis commenced from commercially available starting materials, 4-hydroxy benzaldehyde and phenylbutanoic acid. The features of the synthetic strategy are Wittig olefination and Sharpless asymmetric dihydroxylation

Enantioselective synthesis of bronchodilating agent (R)-Salmeterol

Synthesis of β2-adrenoreceptor agonist bronchodilator (R)-Salmeterol has been described with good yields. The synthesis commenced from commercially available starting materials, 4-hydroxy benzaldehyde and phenylbutanoic acid. The features of the synthetic strategy are Wittig olefination and Sharpless asymmetric dihydroxylation.

Inferior alveolar nerve injury with laryngeal mask airway: a case report

<p>Abstract</p> <p>Introduction</p> <p>The incidence of damage to the individual cranial nerves and their branches associated with laryngeal mask airway use is low; there have been case reports of damage to the lingual nerve, hypoglossal nerve and recurrent laryngeal nerve. To the best of our knowledge we present the first reported case of inferior alveolar nerve injury associated with laryngeal mask airway use.</p> <p>Case presentation</p> <p>A 35-year-old Caucasian man presented to our facility for elective anterior cruciate ligament repair. He had no background history of any significant medical problems. He opted for general anesthesia over a regional technique. He was induced with fentanyl and propofol and a size 4 laryngeal mask airway was inserted without any problems. His head was in a neutral position during the surgery. After surgery in the recovery room, he complained of numbness in his lower lip. He also developed extensive scabbing of the lower lip on the second day after surgery. The numbness and scabbing started improving after a week, with complete recovery after two weeks.</p> <p>Conclusion</p> <p>We report the first case of vascular occlusion and injury to the inferior alveolar nerve, causing scabbing and numbness of the lower lip, resulting from laryngeal mask airway use. This is an original case report mostly of interest for anesthetists who use the laryngeal mask airway in day-to-day practice. Excessive inflation of the laryngeal mask airway cuff could have led to this complication. Despite the low incidence of cranial nerve injury associated with the use of the laryngeal mask airway, vigilant adherence to evidence-based medicine techniques and recommendations from the manufacturer's instructions can prevent such complications.</p

Radial artery pseudo aneurysm after percutaneous cannulation using Seldinger technique

Cannulation of a peripheral artery in a patient allows for continuous blood pressure (BP) monitoring and facilitates frequent arterial blood gas (ABG) analysis. Complications include thrombosis, embolism risk, haemorrhage, sepsis, and formation of pseudo aneurysms. A 75-year-old male admitted via casualty with a collapse secondary to seizures. Patient was intubated and mechanically ventilated for 7 days. A right radial artery catheter was inserted on admission to casualty. The arterial catheter remained in situ for 7 days. Five days following its removal, the skin site appeared inflamed and a wound swab grew methicillin resistant Staphylococcus aureus (MRSA). Eight days later a distinct bulging of the radial artery was noticed. An ultrasound was done and it showed radial artery pseudoaneurysm, the diagnosis was confirmed by angiogram. Delayed radial artery pseudoaneurysm formation has only been reported in association with infection, and less than twenty of these cases have been reported in the literature

IT infrastructure

This report describes the methods taken to improve the overall IT infrastructure and Web presence of a non-profit organization called The Greater Boston Chapter of the Association for Computing Machinery. The web site incorporated an automated online registration system that utilized various e-commerce features to improve the overall user experience. The overall system was found to be effective in the eyes of both the users and the organization

Effects of Clonidine as an Adjuvant to Lidocaine with Epinephrine in Ultrasound Guided Axillary Brachial Plexus Block: A Randomised Controlled Trial

This study evaluated the effects of adding adjuvant clonidine to lidocaine with epinephrine on the characteristics of ultrasound-guided axillary brachial plexus block (ABPB) for upper extremity surgery. Twenty-four patients were randomised to receive an ultrasound guided ABPB with 20 mL of lidocaine 2% with 1:200,000 epinephrine plus 2 mL of either normal saline 0.9% (Group 1) or a mixture of clonidine 1 µg/kg and normal saline 0.9% (Group 2). The outcome measures that were recorded were the overall onset time and the duration of sensory and motor block. The median (IQR) overall onset time of sensory and motor block was significantly shorter in Group 2 vs. Group 1 (5 (5–7.5) min vs. 10 (8.8–12.5) min; p &lt; 0.001) and (5 (2.5–7.5) min vs. 7.5 (6.3–7.5) min; p = 0.001), respectively. The median (IQR) overall duration of sensory and motor block was significantly longer in Group 2 vs. Group 1 (225 (200–231) min vs. 168 (148–190) min; p &lt; 0.001) and (225 (208–231) min vs. 168(148–186) min; p &lt; 0.001), respectively. In ultrasound-guided ABPB, the addition of clonidine to lidocaine with epinephrine resulted in shorter onset time and prolonged duration of sensory and motor block