Jens Børglum

Distribution Patterns, Dermatomal Anesthesia, and Ropivacaine Serum Concentrations After Bilateral Dual Transversus Abdominis Plane Block

Background and Objectives The ability of transversus abdominis plane (TAP) blocks to anesthetize the upper abdomen remains debatable. We aimed to describe the local anesthetic distribution following ultrasound-guided TAP blocks with repeated magnetic resonance imaging investigations and to relate this to the resulting dermatomal anesthesia. Methods Eight volunteers were included in a randomized, observer-blinded study. Sixty milliliters of ropivacaine 0.375% was administered: 1 injection of 30 mL as a lateral classic TAP block, followed by a sham upper intercostal TAP block, and on the contralateral side, 2 separate 15-mL injections at the upper intercostal and lateral classic TAP plexuses, respectively. The primary outcome measure was magnetic resonance imaging–assessed area expansion of all injectates over a 6-hr period. Dermatomal anesthesia and sequential serum ropivacaine levels were recorded at the same time intervals. Results All injectate areas expanded in a statistically significant manner in the anterior abdominal wall. Lateral classic TAP blocks with 30-mL injectates did not extend into the upper intercostal TAP plexus. The dual 15-mL injectates on the other hemiabdomen remained within the upper intercostal and lateral classic TAP compartments and resulted in significantly (P < 0.018) more widespread dermatomal anesthesia. Measured serum ropivacaine concentrations were below the potential level of toxicity. Conclusions Magnetic resonance imaging analysis revealed a significant time-dependent expansion of injectates. Magnetic resonance imaging and the degree of dermatomal anesthesia confirmed that the upper and lateral TAP compartments do not appear to communicate. Separate injections at the upper intercostal and lateral classic TAP plexuses are necessary to block the entire abdominal wall.

Ultrasound-guided bilateral dual transversus abdominis plane block: a new four-point approach.

Background: We describe a new ultrasound‐guided bilateral dual transversus abdominis plane block. Our hypothesis was that we could anaesthetize both the upper (Th6–Th9) and the lower (Th10–Th12) abdominal wall bilaterally using a four‐point single‐shot technique to provide effective post‐operative analgesia.

Temporal comparison of ultrasound vs. auscultation and capnography in verification of endotracheal tube placement

This study compared the time consumption of bilateral lung ultrasound with auscultation and capnography for verifying endotracheal intubation.

Defining adductor canal block.

used to guide an 18-gauge Tuohy needle into the T12/L1 interspace with minimal bony contact. Loss of resistance to saline was met at a depth of 4.5 cm, and a 20-gauge epidural catheter was threaded easily 4 cm into the epidu space. An 18-gauge 2-inch Crawford needle was used to tunnel the catheter subcutaneously. An anteroposterior and lateral epidurogram was performed with 2 mL of iohexol (Omnipaque 300; GE Healthcare, Cork, Ireland). The catheter position was confirmed at T12 with adequate midline vertical spread in a pattern consistent with posterior and anterior epidural spread (Fig. 1). The patient was returned to the supine position, and the epidural catheter was periodically bolused with 0.25% bupivacaine with 1:200,000 epinephrine intraoperatively to maintain analgesia. The operative procedurewas uneventful. The patient was extubated and later discharged to the ward. Postoperatively, the patient was placed on patient-controlled epidural analgesia with an epidural infusion containing 0.1% ropivacaine, 2 μg/mL fentanyl, and 0.5 μg/mL clonidine. The basal rate was set at 10 mL/h with 2 mL every 30minutes demand. Scheduled oral acetaminophen 650 mg every 6 hours was used as a pain adjunct. On postoperative day (POD) 2, the basal rate was increased to 12 mL/h, and analgesia was reported to be excellent. The epidural catheter was removed on POD 4 after successful transition to oral hydrocodone/ acetaminophen 7.5/500 every 4 hours. She was discharged on POD 4. Both patient and family reported superior analgesia and reduced hospital stay compared with earlier admissions for similar orthopedic operations. Successful placement of an epidural catheter can be a challenging task in children with OPPG given the relative fragility of bony structures and high incidence of preexisting vertebral column abnormalities. However, we suggest that an epidural catheter placed under meticulous fluoroscopic guidance to minimize damage to surrounding tissue may be an appropriate option for children with OPPG undergoing lowerextremity surgery. Indeed, epidural analgesia has been shown to provide postoperative analgesia superior to intravenous patientcontrolled analgesia and may also reduce hospital length of stay. Inadequately managed acute pain may possibly lead to chronic pain states, and this must be taken into consideration when planning anesthetics for patients with chronic painful diseases such as OPPG. Imaging modalities such as ultrasound and fluoroscopy continue to increase the safety of acute painmanagement techniques, and the option of regional anesthesia should be considered in all eligible patients to reduce the costs of inadequately treated perioperative pain.

Ultrasound-guided continuous suprascapular nerve block for adhesive capsulitis: one case and a short topical review

We present a case with an ultrasound‐guided (USG) placement of a perineural catheter beneath the transverse scapular ligament in the scapular notch to provide a continuous block of the suprascapular nerve (SSN). The patient suffered from a severe and very painful adhesive capsulitis of the left shoulder secondary to an operation in the same shoulder conducted 20 weeks previously for impingement syndrome and a superior labral anterior–posterior tear. Following a new operation with capsular release, the placement of a continuous nerve block catheter subsequently allowed for nearly pain‐free low impact passive and guided active mobilization by the performing physiotherapist for three consecutive weeks. This case and a short topical review on the use of SSN block in painful shoulder conditions highlight the possibility of a USG continuous nerve block of the SSN as sufficient pain management in the immediate post‐operative period following capsular release of the shoulder. Findings in other painful shoulder conditions and suggestions for future studies are discussed in the text.

The Optimal Analgesic Block for Total Knee Arthroplasty.

Abstract Peripheral nerve block for total knee arthroplasty is ideally motor sparing while providing effective postoperative analgesia. To achieve these goals, one must understand surgical dissection techniques, distribution of nociceptive generators, sensory innervation of the knee, and nerve topography in the thigh.

Structured approach to ultrasound-guided identification of the cricothyroid membrane: a randomized comparison with the palpation method in the morbidly obese

Editor—Correct identification of the cricothyroid membrane is crucial in preparation for emergency airway management. However, the conventional method, inspection and palpation, has a low success rate, especially in women (24–35%). We have previously described a structured stepwise method for ultrasonographic identification of the cricothyroid membrane, 4 in which it is not necessary to see or palpate any landmarks on the neck for successful identification. Themethod involves ultrasonographic identification of the trachea in the transverse plane, rotating the transducer to the longitudinal plane, and identifying the image of the anterior parts of the tracheal rings and the cricothyroid cartilage. Using its ability to cast a shadow on the ultrasound image, an i.v. needle is slid between the transducer and the skin, without penetrating the skin, until it is immediately cranial to the cricoid cartilage, thus indicating the cricothyroid membrane (Fig. 1 Q2 ). We tested the effectiveness of the stepwise approach in the hand of airway-ultrasound naive anaesthetists. After Ethics Committee approval, written consent, and trial registration, 35 anaesthetists, with a mean of 6 yr experience in clinical anaesthesia, completed a structured training programme consisting of an e-learning module, followed by a 20 min lecture, and 20 min hands-on training on live models. Subsequently, the anaesthetists’ ability to identify the cricothyroid membrane both with the palpation method and with ultrasonography was tested in a crossover randomized-sequence test on a morbidly obese female, height 166 cm, weight 125 kg, and BMI 45.3 kg m. Both attemptswere timed and videotaped. The timing started when the finger or the ultrasound probe touched the skin of the neck. With both methods, the anaesthetist was instructed to place an i.v. needle (as a marker) transversely on the skin where he or she found the cricothyroid membrane to be. When

Verification of endotracheal intubation in obese patients – temporal comparison of ultrasound vs. auscultation and capnography

Ultrasound (US) may have an emerging role as an adjunct in verification of endotracheal intubation. Obtaining optimal US images in obese patients is generally regarded more difficult than for other patients. This study compared the time consumption of bilateral lung US with auscultation and capnography for verifying endotracheal intubation in obese patients.

Redefining the adductor canal block.

FIGURE 1. The photographs show a cadaver limb from a man (A) and a woman (B). The distance from the base of patella (red) to the anterior superior iliac spine (blue) is 50 cm in the male limb and 44 cm in the female limb. The midpoint (cyan) is 25 cm proximal to the base of the patella in the male and 22 cm in the female limb. The midpoint is approximately 9 cm from the upper margin (magenta) of the AC in themale and 7.5 cm in the female limb. The distance from the lower border of the greater trochanter (green) to the base of patella (red) is 32 cm in the male and 29 cm in the female limb, and the midpoint (yellow) is at the level of the AC. We want to thank Jæger and colleagues for responding to our concerns about the so-called adductor canal block (ACB). However, some important issues require further clarification. Jæger et al state that the anatomical basis of the ACB has academic interest but limited clinical relevance. Because we agree with Alon Winnie that “regional anesthesia is simply an excercise of applied anatomy,”we believe that it is highly relevant to discuss and understand the anatomical basis of ACB. The needle insertion point for the ACB as defined by Jæger et al—and in past publications by the same research group—is the midpoint between the anterior superior iliac spine and the base of the patella. Jæger et al insist that this point is per definition within the adductor canal

A randomised cross-over comparison of the transverse and longitudinal techniques for ultrasound-guided identification of the cricothyroid membrane in morbidly obese subjects.

We compared the transverse and longitudinal approaches to ultrasound‐guided identification of the cricothyroid membrane, to determine which was faster and more successful. Forty‐two anaesthetists received a one‐hour structured training programme consisting of e‐learning, a lecture and hands‐on training, and then applied both techniques in a randomised, cross‐over sequence to obese females with body mass index 39.0 – 43.9 kg.m−2. The mean (SD) time to identify the cricothyroid membrane was 24.0 (12.4) s using the transverse technique compared with 37.6 (17.9) s for the longitudinal technique (p = 0.0003). Successful identification of the cricothyroid membrane was achieved by 38 (90%) anaesthetists using either technique. All anaesthetists were successful in identifying the cricothyroid membrane with at least one of the techniques. We advocate the learning and application of these two techniques for identification of the cricothyroid membrane before starting anaesthesia in difficult patients, especially when anatomical landmarks are impalpable. Further use in emergency situations is feasible, if clinicians have experience and the ultrasound machine is readily available.