Precision of traditional approaches for lumbar plexus block: impact and management of interindividual anatomic variability.

BACKGROUND: Traditional methods for approaching the lumbar plexus from the posterior rely on finding the intersection of lines that are drawn based on surface landmarks. These methods may be inaccurate in many cases. The aim of this study was to determine the accuracy of these traditional approaches and determine if modifications could increase their accuracy. METHODS: The lumbar plexus region of 48 cadavers (78 +/- 7 yr; 167 +/- 6 cm; 60 +/- 13 kg; men/women: 29/19) was dissected, and relevant anatomic structures were marked. Needle proximity curves were obtained by triangulation for the five traditional approaches and for vectors from the posterior superior iliac spine directed towards the lumbar spinous processes of L3 and towards L4. RESULTS: Proximity curves (mean +/- SD) showed that except Pandin's approach (13 +/- 5 mm too medial), all others were too lateral: Winnie (17 +/- 8 mm), Chayen (8 +/- 5 mm), Capdevila (6 +/- 4 mm), and Dekrey (17 +/- 6 mm). Further, the curves had a narrow parabolic shape and thus a narrow margin of error. Both diagonal vectors had a significantly higher proximity to the lumbar plexus as compared with traditional approaches with a wide parabola, indicating more error tolerance. Using the vector posterior superior iliac spine-L3 with a length between 1/6-1/3 (= 16-22 mm) of the distance posterior superior iliac spine-L3, a proximity to the lumbar plexus < 5.0 +/- 0.3 mm was reached. CONCLUSION: Improvement of both the proximity and the margin of error is possible by using diagonal landmark vectors. Relying on the position of the posterior superior iliac spine eliminates the sex and sided differences and individual body size, which can be problematic if firm metric distances are used in determining the entry point.

High-resolution ultrasound-guided high interscalene plexus block for carotid endarterectomy.

BACKGROUND AND OBJECTIVES: High-resolution ultrasound imaging (HRUI) allows real-time visualization of peripheral nerves, needle insertion, and the spread of local-anesthetic (LA) solution. We evaluated the feasibility of performing a high interscalene brachial-plexus block for carotid endarterectomy by means of HRUI, thereby limiting the amount of LA to the dose required to sufficiently surround the relevant nerve structures. METHODS: The interscalene brachial plexus was localized in the interscalene groove at its most cephalad point in 14 patients undergoing carotid endarterectomy by use of an ultrasound device with a 17.5 MHz transducer. Up to 20 mL of ropivacaine 0.5% was injected. RESULTS: In all patients, HRUI allowed clear delineation of the upper part of the interscalene brachial plexus at the level of the 4th cervical vertebra appearing as 1 hypoechoic, roundish, hypodense node located in a distance of 1.5 +/- 0.3 cm to the skin, 1.5 +/- 0.2 cm lateral to the common carotid artery, and 0.6 +/- 0.2 cm from the transverse process of the spine. Likewise HRUI allowed a clear delineation of minor blood vessels and adjacent anatomic structures, as well as accurate placement of the needle close to the nerves. Real-time observation of LA spread during injection was possible, even in increments of less than 1 mL. CONCLUSIONS: High-resolution ultrasonic imaging allows clear depiction of the target tissues and facilitates accurate needle placement during high interscalene brachial-plexus blocks. This technique may minimize the risk of direct puncture-related complications, as well as accidental intravascular injection of LA. The observation of LA spread in all patients, even in small increments of less than 1 mL might enhance safety by limiting the injected LA to the actual demand. Well-placed LA spread could potentially avoid central nervous toxicity caused by intravascular injection or resorption of inadequately high dosages, in particular in nerve blocks of the highly vascularized neck region.

Perioperative complications of radical cystectomy in a contemporary series.

OBJECTIVES: Radical cystectomy is the preferred standard treatment for patients with muscle-invasive bladder cancer. With improvements in intra- and perioperative care lower complication rates have been reported. We retrospectively evaluated our series of patients who underwent radical cystectomy for advanced bladder cancer for perioperative complications as well as operative time, postoperative hospital stay and transfusion rates. PATIENTS AND METHODS: Between April 1993 and August 2005, 516 radical cystectomies were performed for muscle infiltrating transitional cell carcinoma and other types of neoplastic diseases of the bladder at our institution. The average age was 66.3 yr (31-89). RESULTS: The perioperative mortality rate was 0.8%. A total of 141 patients (27.3%) developed at least one perioperative complication. The most frequent medical complications were subileus in 20 (3.9%) patients, deep venous thrombosis in 24 (4.7%), and enterocolitis in 10 (1.9%). Surgical complications included pelvic lymphoceles in 42 (8.1%) patients, wound dehiscence in 46 (8.9%), pelvic hematoma in 4 (0.8%), peritonitis in 4 (0.8%) and small bowel obstruction in 4 (0.8%). The total early reoperation rate was 6.2%. Operative time, postoperative hospital stay and average number of blood units transfused decreased over the period 1993-2005. CONCLUSIONS: Radical cystectomy today is a procedure with an acceptable rate of perioperative morbidity and mortality. Improvements in surgical technique and anaesthesia as well as increased quality of perioperative care in recent years have resulted in reduced morbidity and shorter hospital stay.

Misplacement of a psoas compartment catheter in the subarachnoid space.

BACKGROUND AND OBJECTIVES: This case report describes an unusual cause of misplacement of an indwelling catheter in the subarachnoid space after primary psoas compartment block in a patient undergoing total knee arthroplasty. CASE REPORT: A 67-year-old woman presenting for total knee joint replacement received a combination of continuous psoas compartment block and sciatic nerve block. Neurostimulation and additional ultrasound guidance were used for identification of the lumbar plexus. After elicitation of a quadriceps motor response, a negative aspiration test, and an uneventful test dose, 20 mL ropivacaine 0.375% and 20 mL mepivacaine 1% were injected. Despite difficult ultrasound conditions because of intestinal air, local anesthetic spread was observed paravertebrally at the medial border of the psoas muscle as usual. A catheter was then advanced 7 cm through the insulated directional puncture needle. An additional sciatic nerve block was performed by using Labat's approach. Ten minutes after injection unilateral sensory block was noted and surgery was started. After uneventful surgery, bilateral sensory block to the T4 level and complete motor block in both lower limbs was detected. A second aspiration test was negative, and an epidural block was suspected. For verification of the catheter tip location, a computed tomography scan with contrast dye was performed revealing catheter placement in the subarachnoid space. The catheter was removed and showed a kink about 7 cm from the tip. After regression of the neuraxial block, lumbar plexus block persisted for another 2 hours. CONCLUSION: An additional test dose via the catheter is recommended if the indwelling catheter is inserted after injection of the local anesthetics through the puncture needle. If epidural anesthesia occurs, an x-ray of the catheter is advisable because negative aspiration via catheter does not rule out subarachnoid catheter location.

Large solitary fibrous tumor of the seminal vesicle.

Solitary fibrous tumors show a classic morphologic pattern ("patternless pattern") consisting mainly of a proliferation of bland spindle cells with varying amounts of thick, often hyalinized or keloid-like, intercellular collagen bundles. Immunohistochemistry shows a strong reactivity for CD34 antigen, vimentin, and, in a variable percentage, bcl-2 antigen. We report the case of a 50-year-old man with a large solitary fibrous tumor located in the pelvic cavity with a rare nonspecific histologic pattern of pseudovascular formations. The patient underwent pelvic exenteration with orthotopic continent urinary diversion and sigmoid-J-pouch bowel reconstruction. No signs of tumor recurrence were noted within 24 months of surgery.