Quantification of Dermal Microcirculatory Changes after Topical Administration of Capsaicin: A Randomized Placebo-Controlled Study in 46 Subjects.

BACKGROUND: Dermal blood flow is crucial for wound healing and survival of flaps in dermatologic surgery. To improve flap viability in cases of compromised perfusion topical agents can easily be applied. The aim of this placebo-controlled study was to characterize changes of DBF in healthy subjects by quantitatively assessing perfusion dynamics after application of capsaicin to establish a reference for measurements at injured sites. METHODS: In 46 healthy subjects perfusion dynamics after local application with capsaicin and placebo was noninvasively assessed, determining cutaneous oxygen saturation, relative hemoglobin count and blood flow using an Oxygen-to-See device. RESULTS: A significant raise in superficial (162% p = 0.000) and deep (144%, p = 0.000) skin oxygenation after 30 min was provoked. A highly significant raise in measurements of flow and velocity was present in superficial (523%, p = 0.000) and deep (242%, p = 0.000) sites. CONCLUSION: With the introduced model applied to observe changes in parameters of dermal blood flow in healthy subjects the authors can reliably monitor effects of topically administered capsaicin. This baseline can be used as reference for further studies in the settings of endangered flap survival or critically perfused wounds as has been proven in animal studies.

The Influence of Topically Administered Heparin on Peripheral Microcirculation of the Skin: A Double-Blind, Randomized, Controlled Preliminary Study on 50 Healthy Subjects.

BACKGROUND: Venous thrombosis is the most common cause of flap failure in the first days after surgery. Although heparin is one of the most important antithrombotic substances and is implemented in the therapy of various diseases, there are only a few studies addressing its topical administration in the field of flap surgery. Especially, very little is known about the effects of topical heparin and its impact on microcirculation. In this study we evaluated to what extent topically administered heparin influences skin microcirculation (capillary venous oxygen saturation SO2, blood filling of microvessels, blood flow, and velocity) in healthy subjects. METHODS: Skin perfusion parameters on the forearm were measured with the O2C device in a double-blinded, controlled, and randomized study with 50 healthy subjects after administration of heparin ointment in three different concentrations and a control ointment (dexpanthenol). RESULTS: Topically administrated heparin slightly increased SO2 (max. 187 ± 285 SD or standard deviation % vs. 145 ± 129 SD %), flow (max. 264 ± 427 SD % vs. 151.74 ± 111 SD %), and velocity (max. 153 ± 149 SD % vs. 122 ± 56 SD %) after an incubation time of 60 minutes in comparison to control. No statistically significant difference could be detected regarding heparin concentration. CONCLUSION: As a first important step in possible future implementing of heparin as a topical administration in flap surgery, our data-although not statistically significant-indicate that heparin can improve microcirculation (SO2, flow) in healthy subjects. Nevertheless, further research in subjects with impaired microcirculation is necessary.

Influence of Topical Anesthesia on Superficial Sensitivity: A Double-Blind, Randomized, Placebo-Controlled Study on 48 Healthy Subjects.

BACKGROUND: Topical anesthetics are used in noninvasive transdermal anesthesia to decrease the superficial pain sensation threshold during dermatologic surgery. Combined pain relief and sensitivity loss can avoid discomfort during the surgery. OBJECTIVE: The aim of this placebo-controlled study was to compare the efficacy of 3 commonly used topical agents by collating loss of sensitivity over time. MATERIALS AND METHODS: Three topical anesthetic creams, a topical anti-inflammatory cream, and a moisturizing cream were applied on the left volar forearm of each of the 48 healthy Caucasian participants. Sensitivity was assessed with the dynamic 2-point discrimination and the Semmes-Weinstein test at 0, 60, 90, 120, 150, and 180 minutes after cream application. RESULTS: After 180 minutes, benzocaine showed a significantly lower 2-point discrimination reduction than lidocaine alone and a lidocaine and prilocaine mixture. Sensory threshold measurements by the Semmes-Weinstein test after 60 minutes revealed a significantly higher effect with lidocaine alone and with the lidocaine and prilocaine mixture than with benzocaine. CONCLUSION: The authors found a stronger skin sensitivity reduction by the eutectic lidocaine and prilocaine mixture and lidocaine alone compared with benzocaine. We suggest increased discomfort reduction in topical anesthetic supported dermatologic surgery by the eutectic mixture and lidocaine alone.

Quantitative Analysis of Heel Skin Microcirculation Using Laser Doppler Flowmetry and Tissue Spectrophotometry.

OBJECTIVE: To examine perfusion changes in the heel skin of individuals with and without diabetes mellitus to understand how skin is pathologically affected by diabetes mellitus. METHODS: This case-control study was conducted at an academic hospital in Tuebingen, Germany. A total of 30 subjects were enrolled in the study: 15 with known type 2 diabetes mellitus and 15 without. Each subject was asked to lie in a supine position on a hard lateral transfer mat for 10 minutes. MAIN OUTCOME MEASURES: Heel perfusion was quantitatively assessed directly after relief of pressure and after 3 and 6 minutes after relief of pressure using laser Doppler flowmetry and tissue spectrophotometry. MAIN RESULTS: Directly after relief of pressure, blood flow increased in the superficial skin layers (2 mm below the surface of the skin) in both groups. However, in deep skin layers (8 mm below the surface of the skin), blood flow increased in patients with diabetes mellitus and decreased in healthy patients. Oxygen saturation (SO2) was higher in healthy subjects directly after pressure relief. CONCLUSIONS: The increase in blood flow in superficial skin layers indicates reactive hyperemia after exposure in both groups. The prolonged hyperemia in deep skin layers in patients with diabetes indicates increased tissue vulnerability. Despite the increase in blood flow in deep skin layers, the SO2 and thus supply of tissue in patients with diabetes were reduced.

[Completeness and reproducibility of surgical reports: A retrospective analysis of documentation quality using the example of Dupuytren's disease]. / Vollständigkeit und Plausibilität von Operationsberichten: Eine retrospektive Analyse der Dokumentationsqualität am Beispiel des Morbus Dupuytren.

Background A surgical report is the surgeon's postoperative documentation of the procedure undertaken. The purpose of this study was to evaluate the completeness and accuracy of data extracted from surgical reports, using the example of Dupuytren's disease. Material and Methods Between 1999 and 2007, surgical data were retrospectively collected from all primary Dupuytren's disease procedures performed at an academic department for plastic and reconstructive surgery and analysed for completeness. A surgical report was assessed as complete if data on indication, affected side and finger(s), tourniquet, type of incision and surgical procedure were stated. Surgical reports of residents and consultants were compared with respect to completeness. For the assessment of accuracy, total fasciectomy procedure reports were compared with intra- and postoperative photo-documentation. Results 424 surgical reports of 366 patients were analysed, 275 created by consultants, 149 by residents. Although 49.5 % of all surgical reports were complete, the indication for surgery was omitted in 53 cases. Information on the affected side and finger(s) was missing in 13 and 6 cases, respectively. In 29 reports, no documentation on tourniquet was found, in 5 the surgical method and in 82 reports the type of incision was lacking. A significant difference between surgical reports of residents and consultants was found for documentation of indication and severity of the Dupuytren's disease, as well as the tourniquet, in favour of residents (p < 0.0001). In 37 surgical reports, total fasciectomy was performed, 26 with intra- or postoperative photodocumentation. By comparison, in 11 of 26 cases (42 %), total fasciectomy could not have been performed. Conclusion Surgical reports are sometimes incomplete and imprecise, independently of whether they were created by residents or consultants. Although they are intended as documentation for doctors and not for forensic reasons, it should be in the surgeon's interest to create complete and exact reports. As surgical reports are part of the patient's chart, surgical associations should develop guidlines with information that should manditorily included in surgical reports.

Skin Perfusion Changes within 12 h after Axillary Plexus Block.

BACKGROUND/PURPOSE: An improvement of the blood flow would be beneficial in microvascular upper-extremity reconstruction and in digit replantation. In the present work, skin perfusion changes and their duration due to axillary plexus block were quantified. METHODS: The peripheral blood flow of the upper extremities in 20 patients undergoing trapeziectomy under axillary plexus block was analyzed. RESULTS: Laser Doppler spectrophotometry was used to measure perfusion factors over a 12-h period, with the contralateral hand acting as the control. Axillary plexus block produced a significant increase of peripheral oxygen saturation (117 ± 35% vs. control 93 ± 22%, p = 0.019), peripheral blood flow (220 ± 166% vs. 130 ± 77%, p = 0.037), and velocity (164 ± 58% vs. 117 ± 45%, p = 0.011). CONCLUSION: Axillary plexus block produces an improvement of peripheral tissue oxygen saturation of the upper extremities over the first 6 h after the inception of anesthesia. This suggests a potential benefit especially for critically perfused tissues.

Quantification of the vasodilatory effect of axillary plexus block. A prospective controlled study.

BACKGROUND: Axillary plexus block is a common method for regional anesthesia, especially in hand and wrist surgery. Local anesthetics (e.g., mepivacaine) are injected around the peripheral nerves in the axilla. A vasodilatory effect due to sympathicolysis has been described, but not quantified. MATERIALS AND METHODS: In a prospective controlled study between October 2012 and July 2013, we analyzed 20 patients with saddle joint arthritis undergoing trapeziectomy under axillary plexus block. Patients received a mixture of mepivacaine 1% and ropivacaine 0.75% in a 3:1 ratio. The measurements were carried out on the plexus side and the contralateral hand, which acted as the control. Laser-Doppler spectrophotometry (oxygen to see [O2C] device) was used to measure various perfusion factors before and after the plexus block, after surgery and in 2-h intervals until 6 h postoperatively. RESULTS: Compared with the contralateral side, the plexus block produced an enhancement of tissue oxygen saturation of 117.35 ± 34.99% (cf. control SO2: 92.92 ± 22.30%, P < 0.010) of the baseline value. Furthermore, blood filling of microvessels (rHb: 131.36 ± 48.64% versus 109.12 ± 33.25%, P < 0.0062), peripheral blood flow (219.85 ± 165.59% versus 129.55 ± 77.12%, P < 0.018), and velocity (163.86 ± 58.18% versus 117.16 ± 45.05%, P < 0.006) showed an increase of values. CONCLUSIONS: Axillary plexus block produces an improvement of peripheral tissue oxygen saturation of the upper extremity over the first 4 h after the inception of anesthesia.

Meniscus body position, size, and shape in persons with and persons without radiographic knee osteoarthritis: quantitative analyses of knee magnetic resonance images from the osteoarthritis initiative.

OBJECTIVE: To quantitatively evaluate the position, size, and shape of the menisci in subjects with radiographic knee osteoarthritis (OA) compared to subjects without OA, using magnetic resonance imaging (MRI). METHODS: We studied the right knees of 39 Osteoarthritis Initiative participants (24 women and 15 men with a mean age of 59.6 ± 8.7 years) with medial compartment radiographic tibiofemoral OA (Kellgren/Lawrence grade of 2 or 3). Subjects were matched individually for age, sex, and height to controls without knee OA and without risk factors for knee OA. The right knees of the controls were used as references. One observer performed manual segmentation of the tibial plateau and the medial and lateral meniscus based on a coronally reconstructed double-echo steady-state sequence with water excitation, focusing on 5 central 3T MRIs. RESULTS: In OA knees, there was less meniscal coverage of the medial tibial plateau (435 mm(2) versus 515 mm(2) ; P = 0.0004), the medial meniscus body showed more extrusion (2.64 mm versus 0.53 mm; P < 0.0001), and the peripheral margin had a more convex shape, i.e., bulged more (mean 0.61 mm versus 0.27 mm; P < 0.0001). The thickness or volume of the medial meniscus body of OA knees did not differ substantially from reference knees. In contrast, in OA knees the lateral meniscus body had a larger volume (mean 266 mm(3) versus 224 mm(3) ; P = 0.0005) and extruded more (mean 1.16 mm versus -1.01 mm; P < 0.0001), and the external margin bulged more (mean 0.53 mm versus 0.35 mm; P < 0.0001), than in reference knees. CONCLUSION: Our findings indicate altered meniscal position and shape (i.e., more bulging) in both compartments in medial compartment knee OA. These changes may be important features of OA pathogenesis and/or disease consequences.

Relationship of 3D meniscal morphology and position with knee pain in subjects with knee osteoarthritis: a pilot study.

OBJECTIVES: To explore whether quantitative, three-dimensional measurements of meniscal position and size are associated with knee pain using a within-person, between-knee study design. METHODS: We studied 53 subjects (19 men, 34 women) from the Osteoarthritis Initiative, with identical radiographic OA grades in both knees, but frequent pain in one and no pain in the other knee. The tibial plateau and menisci were analyzed using coronally reconstructed double echo steady-state sequence with water excitation (DESSwe) MRI. RESULTS: The medial meniscus covered a smaller proportion of the tibial plateau (-5%) and displayed greater extrusion of the body (+15%) in painful than in painless knees (paired t-test; p < 0.05). The external margin of the lateral meniscus showed greater extrusion of the body in painful knees (+22%; p = 0.03), but no significant difference in the position of its internal margin or tibial coverage. Medial or lateral extrusion ≥3 mm was more frequent in painful (n = 23) than in painless knees (n = 12; McNemar's test; p = 0.02). No significant association was observed between meniscal size and knee pain. CONCLUSIONS: These data suggest a relationship between extrusion of the meniscal body, as measured with quantitative MRI, and knee pain in subjects with knee OA. Further studies need to confirm these findings and their clinical relevance.

Interobserver reproducibility of quantitative meniscus analysis using coronal multiplanar DESS and IWTSE MR imaging.

The objective of this study was to determine the interobserver reproducibility of quantitative measures of meniscus size and position, and to compare the interobserver reproducibility and agreement between a double echo steady state water excitation and an intermediately-weighted turbo spin-echo sequence. Eight knees (four healthy, four with radiographic knee osteoarthritis) from the Osteoarthritis Initiative cohort were studied. Manual segmentation of the menisci was performed by three observers and quantitative measures of meniscus size and position (i.e., extrusion) computed using image analysis software. The root mean square interobserver reproducibility error (e.g., 5.4% for medial meniscus volume with double echo steady state and 8.4% with intermediately-weighted turbo spin-echo) was found considerably smaller than the intersubject variability (average ratio ~1:3). The lowest interobserver reproducibility error for meniscus extrusion was obtained for the central five coronal slices across the tibial surface. Quantitative meniscus measures from double echo steady state and intermediately-weighted turbo spin-echo were highly correlated (r = 0.71 to 0.99 for the medial meniscus).

Comparison of experimental aneurysms embolized with second-generation embolic devices and platinum coils.

PURPOSE: The purpose of the study was to compare the performance of second-generation embolic devices with that of platinum coils in experimental aneurysms. METHODS: Microsurgically constructed bifurcation aneurysms in rabbits were embolized with platinum coils (n = 7), HydroCoils 10 (n = 10), HydroSoft (n = 14) or Cerecyte (n = 6) devices. After 1 month, angiographic occlusion was scored and the aneurysms were histologically evaluated by light microscopy. Continuous and ordinal results were compared using ANOVA/Tukey-Kramer HSD and chi(2) tests respectively. RESULTS: Angiographic occlusion at follow-up was increased in the HydroCoil and HydroSoft groups and decreased in the platinum coil and Cerecyte groups. Fibrovascular tissue was observed in the sac of the Cerecyte group, while mixtures of fibrovascular tissue and fibrinous thrombus were observed in the other three groups. The inflammatory response and endothelialization of the neck were similar in all groups. CONCLUSIONS: Expansile hydrogel devices have led to increased progressive occlusion, while degradable polymer devices led to an increased rate of thrombus organization compared with platinum coils.