Perfusion Monitoring Shows Minimal Blood Flow From the Flap Pedicle to the Tarsoconjunctival Flap.

BACKGROUND: A previous study in pigs has shown that the pedicle of the tarsoconjunctival flap does not appear to have adequate blood perfusion. The aim of this study was to monitor perfusion in tarsoconjunctival flaps in patients with large lower eyelid defects resulting from tumor surgery. METHODS: The modified Hughes procedure was performed in 13 patients. Blood perfusion was monitored using laser Doppler velocimetry and laser speckle-contrast imaging. RESULTS: Blood flow decreased gradually from the pedicle base to the end of the flap and was 19% at the flap base, 11% in the middle of the flap, and 4% in the distal end of the flap. The flaps survived, and there was no tissue necrosis. CONCLUSIONS: Tarsoconjunctival tissue survival does not seem to be dependent on a conjunctival flap. Free tarsoconjunctival grafts or composite grafts might be considered as viable alternatives in reconstruction of major eyelid defects.

A waiting time of 7 min is sufficient to reduce bleeding in oculoplastic surgery following the administration of epinephrine together with local anaesthesia.

OBJECTIVE: The time taken to reach maximal haemostatic effect following local anaesthesia with epinephrine is generally believed to be <10 min. This is based on clinical experience and indirect measurements of perfusion using methods such as laser Doppler flowmetry and oxygen spectroscopy. However, the only study in which bleeding has been measured quantitatively in an intra-operative setting in humans showed that the full haemostatic effect was not achieved until 30 min after anaesthesia. The aim of this study was to determine the time taken to reach maximum haemostatic effect when using epinephrine for local anaesthesia in oculoplastic surgery. METHODS: Intra-operative bleeding following infiltration anaesthesia with either lidocaine 20 mg/ml (2%) or lidocaine + epinephrine 12.5 µg/ml (1:80 000) was measured after 7, 15 and 30 min in the eyelids of 16 patients undergoing upper eyelid blepharoplasty. RESULTS: Bleeding was decreased by 74.6% (with 95% CI, 6.16-87.6%) 7 min after the injection of lidocaine + epinephrine (p = 0.0048) compared with lidocaine without epinephrine. There was no further decrease in bleeding after 15 or 30 min (p = n.s.). CONCLUSION: The optimal time for skin incision in eyelid surgery is within 7 min of injection of lidocaine with epinephrine. Waiting longer does not lead to a further decrease in bleeding.

Blood Perfusion in Human Eyelid Skin Flaps Examined by Laser Speckle Contrast Imaging-Importance of Flap Length and the Use of Diathermy.

PURPOSE: It is well known that blood perfusion is important for the survival of skin flaps. As no study has been conducted to investigate how the blood perfusion in human eyelid skin flaps is affected by the flap length and diathermy, the present study was carried out to investigate these in patients. METHODS: Fifteen upper eyelids were dissected as part of a blepharoplastic procedure, releasing a 30-mm long piece of skin, while allowing the 5 mm wide distal part of the skin to remain attached, to mimic a skin flap (hereafter called a "skin flap"). Blood perfusion was measured before and after repeated diathermy, using laser speckle contrast imaging. RESULTS: Blood perfusion decreased from the base to the tip of the flap: 5 mm from the base, the perfusion was 69%, at 10 mm it was 40%, at 15 mm it was 20%, and at 20 mm it was only 13% of baseline values. Diathermy further decreased blood perfusion (measured 15 mm from the base) to 13% after applying diathermy for the first time, to 6% after the second and to 4% after the third applications of diathermy. CONCLUSIONS: Blood perfusion falls rapidly with distance from the base of skin flaps on the human eyelid, and diathermy reduces blood perfusion even further. Clinically, it may be advised that flaps with a width of 5 mm be no longer than 15 mm (i.e., a width:length ratio of 1:3), and that the use of diathermy should be carefully considered.

Statin treatment and risk of recurrent venous thromboembolism: a nationwide cohort study.

OBJECTIVES: Statins may decrease the risk of primary venous thromboembolism (VTE), that is, deep vein thrombosis (DVT) and pulmonary embolism (PE) but the effect of statins in preventing recurrent VTE is less clear. The aim of this study was therefore to investigate the association between statin therapy and risk of recurrent VTE. DESIGN: A prospective cohort study. SETTING: All hospitals in Denmark. PARTICIPANTS: All patients with a hospital diagnosis of VTE in Denmark during 1997-2009 associated with a warfarin or heparin prescription were identified. MAIN OUTCOME MEASURES: Adjusted HR of recurrent hospitalised VTE (ie, fatal or non-fatal DVT or PE) associated with use of statins. RESULTS: 44 330 patients with VTE were included in the study. Of these 3914 were receiving statin therapy at baseline. Patients receiving statins were older (68±11 compared to 62±18 years), had more comorbidity and used more medications. The incidence rate for recurrent VTE was 24.4 (95% CI 22.8 to 26.2) per 1000 person-years among statin users and 48.5 (95% CI 47.4 to 49.7) per 1000 person-years among non-statin users. Statin use was associated with a significantly lower risk of a recurrent VTE, adjusted HR 0.74 (95% CI 0.68 to 0.80), compared with no statin use. The association between statin use and risk of recurrent VTE was significantly affected by age. Among younger individuals (≤80 years), statin use was associated with lower risk of recurrent VTE, HR 0.70 (95% CI 0.65 to 0.76) whereas in older individuals (>80 years) statin use was significantly associated with higher risk of recurrent VTE, HR 1.28 (95% CI 1.02 to 1.60), p for interaction=<0.0001. CONCLUSIONS: Statin use was associated with a decreased risk of recurrent VTE.

Association of clopidogrel treatment with risk of mortality and cardiovascular events following myocardial infarction in patients with and without diabetes.

CONTEXT: Pharmacodynamic studies have shown that persistently high platelet reactivity is common in patients with diabetes in spite of clopidogrel treatment. Clinical trials have not convincingly demonstrated that clopidogrel benefits patients with diabetes as much patients without diabetes. OBJECTIVES: To estimate the clinical effectiveness associated with clopidogrel treatment after myocardial infarction (MI) in patients with diabetes. DESIGN, SETTING, AND PATIENTS: By individual-level linkage of the Danish nationwide administrative registries between 2002-2009, patients who were hospitalized with incident MI and who had survived and not undergone coronary artery bypass surgery 30 days after discharge were followed up for as long as 1 year (maximally until December 31, 2009). Adjusted for age, sex, comorbidity, calendar year, concomitant pharmacotherapy, and invasive interventions, hazard ratios that were associated with clopidogrel in patients with and without diabetes were analyzed by Cox proportional-hazard models and propensity score-matched models. MAIN OUTCOME MEASURES: All-cause mortality, cardiovascular mortality, and a composite end point of recurrent MI and all-cause mortality. RESULTS: Of the 58,851 patients included in the study, 7247 (12%) had diabetes and 35,380 (60%) received clopidogrel. In total, 1790 patients (25%) with diabetes and 7931 patients (15%) without diabetes met the composite end point. Of these, 1225 (17%) with and 5377 (10%) without diabetes died. In total, 978 patients (80%) with and 4100 patients (76%) without diabetes died of events of cardiovascular origin. For patients with diabetes who were treated with clopidogrel, the unadjusted mortality rates (events/100 person-years) were 13.4 (95% CI, 12.8-14.0) vs 29.3 (95% CI, 28.3-30.4) for those not treated. For patients without diabetes who were treated with clopidogrel, the unadjusted mortality rates were 6.4 (95% CI, 6.3-6.6) vs 21.3 (95% CI, 21.0-21.7) for those not treated. However, among patients with diabetes vs those without diabetes, clopidogrel was associated with less effectiveness for all-cause mortality (HR, 0.89 [95% CI, 0.79-1.00] vs 0.75 [95% CI, 0.70-0.80]; P for interaction, .001) and for cardiovascular mortality (HR, 0.93 [95% CI, 0.81-1.06] vs 0.77 [95% CI, 0.72-0.83]; P for interaction, .01) but not for the composite end point (HR, 1.00 [95% CI, 0.91-1.10] vs 0.91 [95% CI, 0.87-0.96]; P for interaction, .08). Propensity score-matched models gave similar results. CONCLUSION: Among patients with diabetes compared with patients without diabetes, the use of conventional clopidogrel treatment after MI was associated with lower reduction in the risk of all-cause death and cardiovascular death.