Review of the Evaluation and Treatment of Vasovagal Reactions in Outpatient Procedures.

BACKGROUND: A vasovagal reaction is a commonly encountered event in outpatient procedures. There is a paucity of discussion on vasovagal reactions (VVRs) in the dermatologic surgery literature. However, recent investigations in the physiology, evaluation, and treatment of VVRs have been reported in other specialties. OBJECTIVE: A comprehensive review of the physiology, evaluation, treatment, and prevention of VVRs. MATERIALS AND METHODS: A search as performed using the PubMed/MEDLINE databases. Search terms included "vasovagal," "vasovagal reaction," "syncope," "reflex syncope," "neurocardiogenic syncope," and "fainting." RESULTS: Studies demonstrate greater understanding in the physiology of a vasovagal reaction. Although permanent sequelae are uncommon, it is important to respond in a prompt manner. A variety of treatment and prevention options are presented. CONCLUSION: Vasovagal reactions should be carefully evaluated. Additional studies may provide greater data in understanding and managing vasovagal reactions.

Finer Needles Reduce Pain Associated With Injection of Local Anesthetic Using a Minimal Insertion Injection Technique.

BACKGROUND: The injection of local anesthetic into the skin is often the only memorable event described by the patient after dermatologic procedures. OBJECTIVE: The authors compared the pain felt during injection of local anesthetic using a minimal needle insertion technique with a 30- or 33-gauge needle. MATERIALS AND METHODS: Three hundred eighteen patients with tumors on the head and neck were injected with lidocaine using a previously described technique with either a 30- or 33-gauge needle. After injection, patients were surveyed using the visual assessment scale for pain. RESULTS: Seventy-seven percent of patients felt no pain with injection on the face using a 33-gauge needle compared with 64% with a 30 gauge, whereas 94% of patients felt no pain on the scalp with a 33-gauge needle compared with 54% with a 30 gauge. Visual analog scale scores were also significantly decreased on the face and scalp using the smaller needle. There was no difference in pain between the 2 needles with injection on the neck. CONCLUSION: This study further validates the use of this technique for the injection of lidocaine and the preference of a 33 gauge over a 30-gauge needle for the initial injection on the face and scalp.

Synovial inflammation plays a greater role in post-traumatic osteoarthritis compared to idiopathic osteoarthritis in the Hartley guinea pig knee.

BACKGROUND: The objective of this study was to evaluate the extent of stromal cell-derived factor-1's (SDF-1) involvement in the pathogenesis of idiopathic versus post-traumatic OA by comparing differences in synovial membrane morphology, SDF-1 synovial fluid (SF) concentrations, and matrix metalloproteinase-13 (MMP-13) SF concentrations. METHODS: Thirty-six 3-month-old Hartley guinea pigs were obtained and divided into 6 groups. Upon sacrifice, India Ink staining was used to evaluate gross morphology, Safranin O/Fast green staining was used to assess cartilage damage, H/E staining was employed to visualize the synovium, and SF samples were obtained for biochemical analyses. Sandwich ELISA was used to quantify the SF concentrations of SDF-1 and MMP-13. RESULTS: 12 month-old, idiopathic OA guinea pigs and 5.5 month-old ACLT animals had comparable cartilage damage when evaluated by the Modified Mankin Score. SDF-1 and MMP-13 concentrations were not statistically different between the two groups. The synovial membrane of the 5.5 month ACLT group had severe synovitis compared to the idiopathic OA group. CONCLUSION: In this study, it was found that synovial inflammation, independent of cartilage morphology, SDF-1 concentration, and MMP-13 concentration, was markedly different between idiopathic and post-traumatic OA. These results highlight the differing morphological and biochemical profiles of post-traumatic versus idiopathic osteoarthritis and calls for a more thorough examination of the sole of the synovial membrane in the pathogenesis of post-traumatic osteoarthritis.