Computerized axial tomo-epidurographic and radiographic documentation of unilateral epidural analgesia

A 23-year-old primigravid patient who received epidural analgesia for pain of labour presented with persistent, apparently irremediable, unilateral analgesia. Computerized axial tomo-epidurography demonstrated absence of circumferential spread due to lateral placement of the catheter. Transforaminal escape of contrast medium into the paravertebral area had occurred and anterior and posterior midline partitioning of the epidural space was obvious. All the usual measures to promote contralateral analgesia, except re-insertion of the catheter, had been tried without success.     

Another (Internal) Epineurium: Beyond the Anatomical Barriers of Nerves

The epineurium has been accepted as the outer anatomical barrier of the peripheral nerves. Our objective was to characterize the microanatomy of the layers surrounding nerves using different tissue-specific staining methods. Two hundred forty-two cross sections of human sciatic and median nerves, and brachial plexuses of eight fresh unembalmed cadavers, were examined. The samples were fixed in formaldehyde solution and stained with hematoxylin–eosin, Masson's trichrome, or epithelial membrane antigen under standard conditions. Because epithelial membrane antigen only stains the perineurium, we demonstrated using hematoxylin–eosin and Masson's trichrome that there were different collagen layers inside and outside the nerves. All fascicles had a collagen layer that surrounded the perineurium and were in close contact with it, with no adipose tissue between them. Unlike the perineurium, this layer, an “internal epineurium,” contained no cells, and it surrounded one or a small group of fascicles. Bundling these fascicles or small groups of fascicles together was the true epineurium, and between the true and internal epineurium, we consistently found an adipose-containing compartment. More proximal to this, the tibial and common peroneal nerves were bundled together by another collagen layer, the circumneurium, which also had a fat-cell-containing compartment deep to it. There were scattered collagen fibers among the adipocytes. Using tissue-specific staining, we were able to demonstrate a collagen layer, the “internal epineurium.” Outside the nerves, we identified several fat-containing concentric compartments. Those compartments were limited by collagen fiber layers that were also similar to the epineurium. Clin. Anat. 33:199–206, 2020. © 2019 Wiley Periodicals, Inc.     

Early experience with continuous cervical paravertebral block using a stimulating catheter

Background and Objectives: This study reports our early experience with continuous cervical paravertebral block (CCPVB) using a stimulating catheter for the management of acute pain after shoulder surgery. METHODS: This prospective observational study presents 256 CCPVB for pain relief after 14 different shoulder operations. Surgery was performed under general anesthesia and blocks were placed prior to induction of general anesthesia (n = 81 [32%]), after induction of general anesthesia (n = 116 [45%]), or postoperatively in the recovery room (n = 59 [23%]). A bolus dose of 30 mL of 0.5% ropivacaine was followed by an infusion of 0.1 mL/kg/h of 0.2% ropivacaine. Patient- or nurse-initiated bolus doses of 10 mL of the same drug were used for breakthrough pain and rescue analgesics were available. Postoperative pain, patient satisfaction, and motor function in different parts of the upper limb were evaluated immediately after surgery (time 0), and then 6, 12, 24, 48, 60 hours, and 14 days postoperatively. RESULTS: An average of 2 (range 1-7) attempts were needed to advance the catheter while still stimulating the nerve. Average postoperative pain ranged from 0.27 +/- 1.04 cm to 0.78 +/- 1.56 cm (mean +/- SD) on a visual analog scale (VAS) (0-10 cm) for the first 48 hours and 3.8 +/- 2.1 cm and 3.5 +/- 2.4 cm at 60 hours and 14 days, respectively. Patient satisfaction on a VAS of 0 to 5 was 4.19 +/- 1.1, 4.28 +/- 1.01, and 4.69 +/- 1.05 at times 0, 6 hours, and 14 days, respectively. Motor function returned to normal in the fingers within 24 hours and in the shoulder within 60 hours. Complications included Horner's syndrome (40%), dyspnea (8%), superficial skin infection (5%), posterior neck pain (22%), subclavian artery puncture (1%), contralateral epidural spread (4%), and 8% of the patients complained of an unpleasant "dead feeling" of the arm. Ninety-one percent of patients would request CCPVB again for future shoulder surgery. There was no evidence of nerve damage.     

Induction of anaesthesia in children

Induction of anaesthesia in children in the age group 2-6 years is a special challenge. In order to minimise emotional and physical stress during induction of anaesthesia by gas inhalation, a toy telephone has been modified to deliver induction gases to the mouthpiece while taped nursery stories can be heard from a small speaker placed in the earpiece. The child holds the hand set and listens to a suitable story, while appropriate concentrations of inhalation agents are adjusted inconspicuously.