The emergence level of the musculocutaneous nerve from the brachial plexus: implications for infraclavicular nerve blocks.

BACKGROUND: In this cadaveric study we assessed the level of the emergence of the musculocutanous nerve (MCN) relative to needle insertion site during infraclavicular block. METHODS: Forty brachial plexi from 20 embalmed adult cadavers were dissected. The MCN was exposed from its origin on the lateral cord to its penetration into the coracobrachialis muscle. The point of emergence of the MCN from the lateral cord relative to a line drawn directly caudad from the anteromedial tip of the coracoid process was measured. A needle was placed predissection using our previously described technique, and the distance from the needletip to the emergence of the MCN was measured. RESULTS: MCN often emerged distal to the coracoid process. At the needle insertion site, 80% of MCN had already emerged from the lateral cord. The distance of emergence ranged from 8.5 cm proximal to 12 cm distal to the coracoid process. CONCLUSION: This anatomical study suggests that MCN may be one of the factors explaining MCN block failure for the single-injection technique of infraclavicular block using lateral needle trajectory.

Postoperative analgesia after total hip arthroplasty: patient-controlled analgesia versus transdermal fentanyl patch.

STUDY OBJECTIVE: To determine whether a new transdermal fentanyl patch (TFP) is a good choice for the postoperative pain management of patients undergoing primary total hip arthroplasty compared with patient-controlled analgesia (PCA). DESIGN: Randomized, prospective study. SETTING: University hospital. PATIENTS: 30 patients undergoing primary total hip arthroplasty. INTERVENTIONS: Patients received either a TFP (group T; Duragesic 50 microg/h, matrix fentanyl patch, Janssen-Cilag) applied approximately 10 hours before induction of general anesthesia and PCA programmed in the postanesthesia care unit (PACU), or PCA programmed in the PACU (group P). MEASUREMENTS: Intraoperative sufentanil and additional postoperative morphine administration were recorded, as well as visual analog scores and routine vital signs at predetermined intervals during the first 48 hours. MAIN RESULTS: Morphine consumption on arrival in the PACU was 3.5+/-3 mg in group T versus 13+/-5 mg in group P (P<0.0001). Visual analog scores on arrival in the PACU were 37+/-22 mm in group T versus 73+/-13 mm in group P (P<0.0001). Cumulative morphine consumption at the 24th hour was 43+/-16 mg in group P and 4+/-3 mg in group T (P<0.0001). Cumulative morphine consumption at the 48th hour was 54+/-26 mg in group P and 5+/-4 mg in group T (P<0.0001). Intraoperative sufentanil consumption was 38+/-15 microg in group T versus 30+/-5 microg in group P (not significant). The sedation score was 0 in both groups during the first 48 postoperative hours. CONCLUSIONS: Preoperative TFP application decreases pain scores and morphine consumption in the PACU and appears to have prolonged effects spanning the first 48 postoperative hours.

Migraine with atypical aura in the recovery room: a sometimes complicated diagnosis!

Migraine is a frequent neurological pathology. However, the diagnosis can be difficult to establish, especially when it is accompanied with an atypical aura that can be confounded with a stroke. We describe a case of 38-yr-old patient who presented just after general anesthesia with a perioperative acute migraine with atypical aura which was wrongly treated as a serious cerebral stroke. The patient had not mentioned migraine in her history before the surgery. This lack of information led to unnecessary therapy.

The paramedian technique: a superior initial approach to continuous spinal anesthesia in the elderly.

BACKGROUND: Spinal anesthesia in elderly patients is frequently associated with significant technical difficulties. Thus, we compared the classical midline approach to the paramedian approach to perform continuous spinal anesthesia (CSA). METHODS: We prospectively studied 40 patients aged >75 yr who underwent open surgical repair of a hip fracture. These patients were randomly allocated to one of two groups: Group M: midline approach, and Group PM: paramedian approach. Patients were positioned in the lateral decubitus to receive CSA at L4-5 level. CSA was considered successful if cerebrospinal fluid was obtained through the needle. In case of initial failure in either approach, the same approach was repeated by the same operator. If two attempts were unsuccessful, the other anatomical approach was used by the same operator. If both approaches failed, a staff anesthesiologist performed a final attempt. In case of failure or insufficient block, the patient received general anesthesia. RESULTS: The success rate after the first attempt was 85% (17) for Group PM and 45% (9) for Group M (P = 0.02). All catheters were successfully introduced. No patient required general anesthesia. Vascular puncture after needle puncture was observed in six patients in Group M versus 0 in Group PM (P = 0.03), but none were of clinical consequence. No other clinically significant complications were observed. CONCLUSION: In summary, after the initial attempt, the paramedian approach is associated with an increased success rate, compared with the midline approach, during the performance of CSA in elderly patients.

Eutectic mixture of local anesthetic (EMLA) decreases pain during humeral block placement in nonsedated patients.

BACKGROUND: We evaluated the potential role of an euctectic mixture of local anesthetic (EMLA) cream application before performing midhumeral block. METHODS: Sixty patients undergoing surgery distal to the elbow amenable to a humeral block were prospectively recruited for the study. The patients were randomly allocated to 1 of 3 groups: Group E: topical EMLA cream 60 min before block plus 2 mL IV normal saline 5 min before procedure; Group P: topical sham cream plus 2 mL IV normal saline, and Group S: topical sham cream plus 0.1 microg/kg of sufentanil in 2 mL solution IV. Pain experienced during skin puncture, and overall pain for the whole procedure were rated using a 100-mm visual analog scale (0: no pain to 100: worst pain). RESULTS: Patients in Group E experienced less pain compared with those in Groups P and S (5 +/- 3 mm vs 33 +/- 20 mm and 30 +/- 18 mm, respectively, P < 0.0001). The pain experienced throughout the complete humeral block was more substantial in Group P than in Group E (P = 0.01). CONCLUSION: The patients who received EMLA cream had less pain with needle puncture as well as throughout the performance of humeral block.

A modified mid-femoral approach to the sciatic nerve block: a correlation between evoked motor response and sensory block.

BACKGROUND: The lateral sciatic mid-femoral block (LSMF), proved to be reliable, safe, and effective on both branches of the sciatic nerve with a single injection. However, we do not know which component of the sciatic nerve (the tibial [T] or the common peroneal [CP]) produces a better success rate when performing a LSMF with a single injection technique. In this prospective study we compared the success rate of the T motor response with the CP motor response. METHODS: Ninety-five patients undergoing ankle or foot surgery were enrolled. Thirty milliliters of 0.475% ropivacaine was injected at the first evoked motor response, either T or CP, with a minimal intensity between 0.3 and 0.5 mA. RESULTS: Seventy-two patients were included in group T and 23 in group CP. The block was considered a success when a complete sensory block of the sciatic nerve was obtained. The success rate was 90% (65) for the T response and 70% (16) for the CP response (P < 0.05). Time to perform the block (CP: 4.5 +/- 3 min vs T: 4.5 +/- 4 min; P = NS) as well as sensory and motor onset times were not significantly different between groups. No complications were observed in either group. CONCLUSION: We conclude that the evoked motor response of the T branch is associated with a higher success rate than a CP response using the modified LSMF block.

A comparison between double-injection axillary brachial plexus block and midhumeral block for emergency upper limb surgery.

In this prospective and randomized study, we compared a double-injection axillary (median and radial nerves) block with a midhumeral block in 90 patients undergoing emergency upper limb surgery. Time to perform the block, success rate, and patient tolerance were evaluated. The time to perform the block was 5 min longer in the midhumeral group. The success rate was similar in both groups (80% and 91% in groups axillary and midhumeral respectively), except for the musculocutaneous nerve. Patient tolerance was better in the axillary group. Double-injection axillary brachial plexus block is superior to midhumeral block for emergency hand surgery.