Comparison of the Different Approaches to Saphenous Nerve Block

Background: The authors compared the efficacy of the different approaches to saphenous nerve block.

Methods: The following approaches to saphenous nerve block were compared in 10 volunteers: perifemoral, transsartorial, block at the medial femoral condyle, below-the-knee field block, and blockade at the level of the medial malleolus. Each volunteer underwent all five blocks, and the interval between blocks was 3-7 days. The sequence of injection was randomized by Latin square design. Sensory blockade at the medial aspects of the leg and foot and the strength of the anterior thigh muscles were noted.

Results: The transsartorial, perifemoral, and below-the-knee field block approaches were more effective than block at the medial femoral condyle in providing sensory anesthesia to the medial aspect of the leg. The transsartorial approach was more effective than block at the medial femoral condyle and below-the-knee field block in providing sensory anesthesia to the medial aspect of the foot. Compared with the perifemoral approach, the transsartorial approach did not cause weakness of the hip flexors and the knee extensors. In volunteers with partial numbness in the medial aspect of the foot, supplemental block of the medial dorsal cutaneous branch of the superficial peroneal nerve resulted in complete sensory blockade.     

Scalene Muscle Injections for Neurogenic Thoracic Outlet Syndrome: Case Series

Abstract: Scalene muscle injections are used to confirm the diagnosis of neurogenic thoracic outlet syndrome and predict the response of patients to surgery. We performed a retrospective study to determine if relief of pain was related to brachial plexus blockade in these patients. Methods: We reviewed the charts of 12 patients who had anterior and middle scalene muscle injections, for neurogenic thoracic outlet syndrome, between April 2009 and September 2010. The injections were performed under ultrasound guidance wherein 2 to 5 mL of 0.25% bupivacaine was injected into the belly of the anterior and scalene muscles. The following were noted: (1) sites of preprocedure pain; (2) volume injected into each of the anterior and middle scalene muscles; (3) presence of numbness after injection; and (4) presence and duration of pain relief. Results: All 12 patients had relief of their pain. Six of the twelve patients developed numbness, which ranged from blockade of the C4‐5, C6‐7, and C4‐T1 dermatomes. In the patients who developed numbness, there was no relationship between the duration of numbness and the duration of pain relief or the location of numbness and the location of pain relief. Conclusions: The relief from scalene muscle injections in patients with neurogenic thoracic outlet syndrome is not related to blockade of the brachial plexus. ?     

Human platelets express Toll-like receptor 3 and respond to poly I:C

Platelets functions in hemostasis have been widely studied. Currently, growing evidence shows that platelets have also a role in the immune innate response. Recently, protein expression of Toll-like receptors (TLR’s) 2, 4, 7, 8, and 9, and the presence of TLRs 1 and 6 mRNA in human platelets was described. Up to now the functionality of TLR-2, 4 and 9 in human platelets has been demonstrated. Due to the relevance of TLRs functions to PAMPS (pathogen-associated molecular patterns) recognizing, we evaluated the presence of TLR3 in human platelets founding low percentages of platelets expressing surface or intracellular TLR3 protein. The activation with thrombin induced an increase in the percentage of platelets expressing surface TLR3 and higher levels of TLR3 expression in the whole population. Human platelets responded to poly I:C by increasing [Ca²⁺]_i, the percentages of cells expressing TLR4 and CD62P, and by releasing CXCL4 and IL-1β in comparison to unstimulated platelets. These results demonstrate that human platelets express TLR3 and are capable of responding to poly I:C, suggesting that these cells might influence the immune innate response when detecting viral dsRNA.     

Superior sagittal sinus thrombosis in a patient with postdural puncture headache

BACKGROUND AND OBJECTIVES: The occurrence of concomitant intracranial pathology in a patient with postdural puncture headache (PDPH) is rare. We present a patient who had a superior sagittal sinus thrombosis in addition to his PDPH. The signs and symptoms of intracranial pathology in patients with dural puncture headache, in addition to their postural headache, are discussed. CASE REPORT: A 32-year-old man with lymphoblastic lymphoma received treatment with daunorubicin, vincristine, and prednisone. He developed postural headache and severe nausea and vomiting after a diagnostic lumbar puncture. Magnetic resonance imaging (MRI) showed superior sagittal sinus (SSS) thrombosis and meningeal enhancement. An epidural blood patch was performed and enoxaparin was prescribed for 6 months. He has remained asymptomatic. CONCLUSIONS: Patients with PDPH have classic postural headache. The occurrence of additional signs and symptoms should alert the clinician to the presence of intracranial pathology. Patients with lymphoblastic lymphoma who had treatment with L-asparaginase and steroid are predisposed to the development of cortical venous thrombosis and may have this syndrome in addition to a dural puncture headache.