Inhaled Amikacin to Prevent Ventilator-Associated Pneumonia.

BACKGROUND: Whether preventive inhaled antibiotics may reduce the incidence of ventilator-associated pneumonia is unclear. METHODS: In this investigator-initiated, multicenter, double-blind, randomized, controlled, superiority trial, we assigned critically ill adults who had been undergoing invasive mechanical ventilation for at least 72 hours to receive inhaled amikacin at a dose of 20 mg per kilogram of ideal body weight once daily or to receive placebo for 3 days. The primary outcome was a first episode of ventilator-associated pneumonia during 28 days of follow-up. Safety was assessed. RESULTS: A total of 850 patients underwent randomization, and 847 were included in the analyses (417 assigned to the amikacin group and 430 to the placebo group). All three daily nebulizations were received by 337 patients (81%) in the amikacin group and 355 patients (83%) in the placebo group. At 28 days, ventilator-associated pneumonia had developed in 62 patients (15%) in the amikacin group and in 95 patients (22%) in the placebo group (difference in restricted mean survival time to ventilator-associated pneumonia, 1.5 days; 95% confidence interval [CI], 0.6 to 2.5; P = 0.004). An infection-related ventilator-associated complication occurred in 74 patients (18%) in the amikacin group and in 111 patients (26%) in the placebo group (hazard ratio, 0.66; 95% CI, 0.50 to 0.89). Trial-related serious adverse effects were seen in 7 patients (1.7%) in the amikacin group and in 4 patients (0.9%) in the placebo group. CONCLUSIONS: Among patients who had undergone mechanical ventilation for at least 3 days, a subsequent 3-day course of inhaled amikacin reduced the burden of ventilator-associated pneumonia during 28 days of follow-up. (Funded by the French Ministry of Health; AMIKINHAL ClinicalTrials.gov number, NCT03149640; EUDRA Clinical Trials number, 2016-001054-17.).

Characteristics, Natural Course and Treatment of Intramuscular Capillary-type Haemangioma: A Systematic Literature Review.

Intramuscular capillary-type haemangiomas (ICTH) are rare vascular anomalies that can easily be misdiagnosed as other entities. A systematic review was performed of all cases of ICTH in the literature since its first description in 1972. An adjudication committee reviewed cases to include only ICTHs. Among 1,143 reports screened, 43 were included, involving 75 patients. The most frequent differential diagnosis was intramuscular venous malformations. The mean age of patients at diagnosis was 21.2 years. ICTH was mainly described as a gradually increasing mass (81.8%), painless (73.9%), that could occur anywhere in the body but most frequently on the head and neck (44.0%). Magnetic resonance imaging (MRI) was mainly used for diagnosis (69.1%) and displayed specific features. The most frequent treatment was complete surgical removal (73.9%), which could be preceded by embolization, and led to complete remission without recurrence in all but 1 case.

Intervention effect estimates in randomised controlled trials conducted in primary care versus secondary or tertiary care settings: a meta-epidemiological study.

BACKGROUND: Many clinical practice guidelines are based on randomised controlled trials conducted in secondary or tertiary care setting and general practitioners frequently question their relevance for primary care patients. Our aim was to compare the intervention effect estimates between primary care setting randomised controlled trials (PC-RCTs) and secondary or tertiary care setting randomised controlled trials (ST-RCTs). METHODS: Meta-epidemiological study of meta-analyses (MAs) of a binary outcome including at least one PC-RCT and one ST-RCT. PC-RCTs were defined as trials recruiting patients in general practices, primary care practices, family practices, community centers or community pharmacies. ST-RCTs were defined as trials recruiting in hospitals, including hospitalized patients, hospital outpatients and patients from emergency departments. For each MA, we estimated a ratio of odds ratio (ROR) by using random-effects meta-regression, with an ROR less than 1 indicating lower estimates of the intervention effect in PC-RCTs than ST-RCTs. Finally, we estimated a combined ROR across MAs by using a random-effects meta-analysis. We performed subgroup analyses considering the type of outcomes (objective vs subjective), type of experimental intervention (pharmacological vs non-pharmacological), and control group (active vs inactive) as well as analyses adjusted on items of the Cochrane Risk of Bias tool. RESULTS: Among 1765 screened reviews, 76 MAs with 230 PC-RCTs and 384 ST-RCTs were selected. The main medical fields were pneumology (13.2%) and psychiatry or addictology (38.2%). Intervention effect estimates did not significantly differ between PC-RCTs and ST-RCTs (ROR = 0.97, 95% confidence interval 0.88 to 1.08), with moderate heterogeneity across MAs (I2 = 45%). Subgroup and adjusted analyses led to consistent results. CONCLUSION: We did not observe any significant difference in intervention effect estimates between PC-RCTs and ST-RCTs. Nevertheless, most of the medical fields in this meta-epidemiological study were not representative of the pathologies encountered in primary care. Further studies with pathologies more frequently encountered in primary care are needed.

Assessing oral comprehension with an eye tracking based innovative device in critically ill patients and healthy volunteers: a cohort study.

PURPOSE: Communication of caregivers and relatives to patients is a major difficulty in intensive care units (ICU). Patient's comprehension capabilities are variable over time and traditional comprehension tests cannot be implemented. Our purpose was to evaluate an oral comprehension test adapted for its automatic implementation using eye-tracking technology among ICU patients. METHODS: Prospective bi-centric cohort study was conducted on 60 healthy volunteers and 53 ICU patients. Subjects underwent an oral comprehension test using an eye-tracking device: Their results and characteristics were collected. The total duration of the test was 2 and a half minutes. RESULTS: While performing the test, 48 patients (92%) received invasive ventilation. Among healthy volunteers, the median rate of right answers was very high (93% [interquartile range 87, 100]), whereas it was lower (33% [20, 67]) for patients. For both groups, a significantly lower right answers rate was observed with advancing age (67% [27, 80] vs. 27% [20, 38] among patients and 93% [93, 100] vs. 87% [73, 93] among healthy volunteers, below and above 60 years of age, respectively) and in case of lack of a bachelor's degree (60% [38, 87] vs. 27% [20, 57] among patients and 93% [93, 100] vs. 87% [73, 93] among healthy volunteers). For patients, the higher the severity of disease was, the lower the rate of correct answers was. CONCLUSION: The eye-tracking-adapted comprehension test is easy and fast to use among ICU patients, and results seem coherent with various potential levels of comprehension as hypothesized in this study.

Factors for success of awake prone positioning in patients with COVID-19-induced acute hypoxemic respiratory failure: analysis of a randomized controlled trial.

BACKGROUND: Awake prone positioning (APP) improves oxygenation in coronavirus disease (COVID-19) patients and, when successful, may decrease the risk of intubation. However, factors associated with APP success remain unknown. In this secondary analysis, we aimed to assess whether APP can reduce intubation rate in patients with COVID-19 and to focus on the factors associated with success. METHODS: In this multicenter randomized controlled trial, conducted in three high-acuity units, we randomly assigned patients with COVID-19-induced acute hypoxemic respiratory failure (AHRF) requiring high-flow nasal cannula (HFNC) oxygen to APP or standard care. Primary outcome was intubation rate at 28 days. Multivariate analyses were performed to identify the predictors associated to treatment success (survival without intubation). RESULTS: Among 430 patients randomized, 216 were assigned to APP and 214 to standard care. The APP group had a lower intubation rate (30% vs 43%, relative risk [RR] 0.70; CI95 0.54-0.90, P = 0.006) and shorter hospital length of stay (11 interquartile range [IQR, 9-14] vs 13 [IQR, 10-17] days, P = 0.001). A respiratory rate ≤ 25 bpm at enrollment, an increase in ROX index > 1.25 after first APP session, APP duration > 8 h/day, and a decrease in lung ultrasound score ≥ 2 within the first 3 days were significantly associated with treatment success for APP. CONCLUSION: In patients with COVID-19-induced AHRF treated by HFNC, APP reduced intubation rate and improved treatment success. A longer APP duration is associated with APP success, while the increase in ROX index and decrease in lung ultrasound score after APP can also help identify patients most likely to benefit. TRIAL REGISTRATION: This study was retrospectively registered in ClinicalTrials.gov at July 20, 2021. Identification number NCT04477655. https://clinicaltrials.gov/ct2/show/NCT04477655?term=PRO-CARF&draw=2&rank=1.

Weekly Sequential Antibioprophylaxis for Recurrent Urinary Tract Infections Among Patients With Neurogenic Bladder: A Randomized Controlled Trial.

BACKGROUND: Recurrent urinary tract infections (R-UTIs) are the main cause of morbidity and hospitalizations in subjects with neurogenic bladder (NB) due to spinal cord injury (SCI). We evaluated the efficacy of weekly oral cyclic antibiotic (WOCA) prophylaxis (ie, the alternate weekly administration of 2 antibiotics) in preventing R-UTIs. METHODS: Randomized (1:1), open-label, superiority-controlled trial compared WOCA prophylaxis to no prophylaxis (control) for 6 months in patients with NB due to SCI, using clean intermittent self-catheterization, and suffering from R-UTIs. Primary outcome was incidence of symptomatic antibiotic-treated UTIs. Secondary outcomes were number of febrile UTIs, number of hospitalizations, WOCA tolerance, antibiotic consumption, number of negative urine cultures, and emergence of bacterial resistance in urinary, intestinal, and nasal microbiota. RESULTS: Forty-five patients were either allocated to the WOCA group (n = 23) or the control group (n = 22). Median (IQR) incidence of symptomatic antibiotic-treated UTIs was 1.0 (0.5-2.5) in the WOCA group versus 2.5 (1.2-4.0) (P = .0241) in the control group. No febrile UTIs were recorded in the WOCA group versus 9 (45.0%) (P < .001) in the control group. The median number of additional antibiotic treatment was 0.0 (IQR, 0.0-2.0) versus 3.0 (2.0-5.0) (P = .004) in the WOCA and control groups, respectively. Only few adverse events were reported. No impact on emergence of bacterial resistance was observed. CONCLUSIONS: WOCA is efficient and well tolerated in preventing R-UTIs in SCI patients. In our study, we did not observe any emergence of antibiotic resistance in digestive and nasal microbiological cultures. CLINICAL TRIALS REGISTRATION: NCT01388413.

Effect of Hydrocortisone on 21-Day Mortality or Respiratory Support Among Critically Ill Patients With COVID-19: A Randomized Clinical Trial.

Importance: Coronavirus disease 2019 (COVID-19) is associated with severe lung damage. Corticosteroids are a possible therapeutic option. Objective: To determine the effect of hydrocortisone on treatment failure on day 21 in critically ill patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and acute respiratory failure. Design, Setting, and Participants: Multicenter randomized double-blind sequential trial conducted in France, with interim analyses planned every 50 patients. Patients admitted to the intensive care unit (ICU) for COVID-19-related acute respiratory failure were enrolled from March 7 to June 1, 2020, with last follow-up on June 29, 2020. The study intended to enroll 290 patients but was stopped early following the recommendation of the data and safety monitoring board. Interventions: Patients were randomized to receive low-dose hydrocortisone (n = 76) or placebo (n = 73). Main Outcomes and Measures: The primary outcome, treatment failure on day 21, was defined as death or persistent dependency on mechanical ventilation or high-flow oxygen therapy. Prespecified secondary outcomes included the need for tracheal intubation (among patients not intubated at baseline); cumulative incidences (until day 21) of prone position sessions, extracorporeal membrane oxygenation, and inhaled nitric oxide; Pao2:Fio2 ratio measured daily from day 1 to day 7, then on days 14 and 21; and the proportion of patients with secondary infections during their ICU stay. Results: The study was stopped after 149 patients (mean age, 62.2 years; 30.2% women; 81.2% mechanically ventilated) were enrolled. One hundred forty-eight patients (99.3%) completed the study, and there were 69 treatment failure events, including 11 deaths in the hydrocortisone group and 20 deaths in the placebo group. The primary outcome, treatment failure on day 21, occurred in 32 of 76 patients (42.1%) in the hydrocortisone group compared with 37 of 73 (50.7%) in the placebo group (difference of proportions, -8.6% [95.48% CI, -24.9% to 7.7%]; P = .29). Of the 4 prespecified secondary outcomes, none showed a significant difference. No serious adverse events were related to the study treatment. Conclusions and Relevance: In this study of critically ill patients with COVID-19 and acute respiratory failure, low-dose hydrocortisone, compared with placebo, did not significantly reduce treatment failure (defined as death or persistent respiratory support) at day 21. However, the study was stopped early and likely was underpowered to find a statistically and clinically important difference in the primary outcome. Trial Registration: ClinicalTrials.gov Identifier: NCT02517489.

Topical use of mammalian target of rapamycin inhibitors in dermatology: A systematic review with meta-analysis.

BACKGROUND: Systemic mammalian target of rapamycin (mTOR) inhibitors are currently used in many dermatologic indications. Their topical use is recent and poorly codified. OBJECTIVE: To provide an overview of the topical use of mTOR inhibitors in dermatologic conditions and evaluate their efficacy and safety. METHODS: A literature search was performed in January 2017. Reports of all studies investigating the use of topical mTOR inhibitors in any dermatology diseases were included. The exclusion criteria were systemic use and mucosal administration. RESULTS: We included 40 studies with a total of 262 patients. In all, 11 dermatologic conditions were found, the most frequent being angiofibromas linked to tuberous sclerosis complex (157 patients). Topical mTOR inhibitors were significantly more efficient than placebo for angiofibromas (relative risk, 2.52; 95% confidence interval, 1.27-5.00; I2 = 0%). The median concentration of sirolimus was 0.1%, with a median treatment duration of 12 weeks. Topical mTOR inhibitors were well tolerated, with only mild or moderate local side effects (mostly irritative) reported. Blood level of sirolimus was not detected in 90% of patients. LIMITATIONS: High heterogeneity in most studies. CONCLUSION: This systematic review supports the efficacy of topical sirolimus for angiofibromas linked to tuberous sclerosis complex, with only local side effects reported. Other indications require further research.

Efficacy and Tolerance of Sirolimus (Rapamycin) for Extracranial Arteriovenous Malformations in Children and Adults.

Managing extracranial arteriovenous malformations is challenging. Sirolimus (rapamycin) is increasingly being used when surgery and embolization are not advised. Because of its anti-angiogenic properties here we report all extracranial arteriovenous malformation cases treated with sirolimus in 2 French tertiary centers for vascular anomalies. The outcomes were efficacy (complete, partial, no response) based on arteriovenous malformation volume and necrosis/hemorrhage and side effects. We retrospectively included 10 patients (7 children). The sirolimus dose ranged from 0.6 to 3.5 mg/m2. Median (interquartile range [IQR]) treatment time was 24.5 (4.5; 35) months. Five patients showed no response and 5 showed partial response at a median (IQR) of 3 (1; 5) months followed in 2 cases by therapeutic resistance (i.e., progressive disease after 9 and 24 months of treatment). The most frequent side effect was mouth ulcers. This study shows poor efficacy of sirolimus for treating extracranial arteriovenous malformations.

Non-antistreptococcal interventions for acute guttate psoriasis or an acute guttate flare of chronic psoriasis.

BACKGROUND: Guttate psoriasis displays distinctive epidemiological and clinical features, making it a separate entity within the heterogeneous group of cutaneous psoriasis types. It is associated with genetic, immune, and environmental factors (such as stress and infections) and usually arises in younger age groups (including children, teenagers, and young adults). There is currently no cure for psoriasis, but various treatments can help to relieve the symptoms and signs. The objectives of treatment when managing an acute flare of guttate psoriasis are to reduce time to clearance and induction of long-term remission after resolution. This is an update of a Cochrane Review first published in 2000; since then, new treatments have expanded the therapeutic spectrum of systemic treatments used for psoriasis. OBJECTIVES: To assess the effects of non-antistreptococcal interventions for acute guttate psoriasis or an acute guttate flare of chronic psoriasis. SEARCH METHODS: We searched the following databases up to June 2018: the Cochrane Skin Specialised Register, CENTRAL, MEDLINE, Embase, and LILACS. We searched five trials registers and checked the reference lists of included studies for further references to relevant randomised controlled trials. We checked the proceedings of key dermatology conferences from 2004 to 2018, and also searched for trials in the US Food and Drug Administration (FDA) database for drug registration. SELECTION CRITERIA: All randomised controlled trials assessing the effects of treatments for acute guttate psoriasis or an acute guttate flare of chronic psoriasis clinically diagnosed in children and adults. This included all topical and systemic drugs, biological therapy, phototherapy (all forms: topical and systemic), and complementary and alternative therapies. We compared these treatments against placebo or against another treatment. We did not include studies on drugs that aim to eradicate streptococcal infection. We did not include studies when separate results for guttate psoriasis participants were not available. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed study eligibility and methodological quality and extracted data. We used standard methodological procedures expected by Cochrane. Our primary outcomes were 'percentage of participants clear or almost clear (i.e. obtaining Psoriasis Area Severity Index (PASI) 100/90 and/or Physician's Global Assessment (PGA) of 0 or 1)' and 'percentage of participants with adverse effects and severe adverse effects'. Our secondary outcomes were 'number of relapses of guttate psoriasis or flares within a period of six months after the treatment has finished', 'percentage of participants achieving a PASI 75 or PGA of 1 or 2', and 'improvement in participant satisfaction measures and quality of life assessment measures'. We used GRADE to assess the quality of the evidence for each outcome. MAIN RESULTS: This review included only one trial (21 participants), which compared fish oil-derived (n-3) fatty acid-based lipid emulsion (50 mL per infusion (1.05 g eicosapentaenoic and 10.5 g docosahexaenoic acid)) (10 participants) to soya oil-derived (n-6) fatty acid-based lipid emulsion (50 mL per infusion (1.05 g eicosapentaenoic and 10.5 g docosahexaenoic acid)) (11 participants) administered intravenously twice daily for 10 days, with a total follow-up of 40 days. The study was conducted in a single centre in Germany in 18 men and three women, aged between 21 and 65 years, who were in hospital with acute guttate psoriasis and had mean total body surface involvement of 25.7% ± 20.4% (range 10 to 90). The study was funded by a company that produces the oil emulsions. We found no other evidence regarding non-antistreptococcal interventions used in clinical practice for guttate psoriasis, such as topical treatments (corticosteroids, vitamin D3 analogues), systemic drugs, biological therapy, and phototherapy.The primary outcomes of the review were not measured, and only one of our secondary outcomes was measured: improvement in participant satisfaction measures and quality of life assessment measures. However, the study authors did report that there was rare skin irritation at the site of peripheral intravenous route, but the number of affected participants was not provided.Improvement between baseline and day 10, using a non-validated score assessed by participants themselves daily based on five items (appearance of lesions, impairment of daily life, pruritus, burning, and pain), was greater in the group that received the fish oil-derived (n-3) fatty acid-based lipid emulsion (75%) than in the group receiving the soya oil-derived (n-6) fatty acid-based lipid emulsion (18%) (one trial, 21 participants). However, these results are uncertain as they are based on very low-quality evidence. AUTHORS' CONCLUSIONS: There is no evidence regarding topical and systemic drugs, biotherapy, or phototherapy in guttate psoriasis (we did not consider drugs that aimed to eradicate streptococcal infection because these are assessed in another Cochrane Review). We are uncertain of the effect of intravenously administered lipid emulsion on guttate psoriasis because the quality of the evidence is very low, due to risk of bias (unclear risk of bias for all domains), indirectness (the trial only included adults, and the follow-up from baseline was only 10 days), and imprecision (small number of participants).This review highlights the need for trials assessing the efficacy and safety of phototherapy and topical and systemic drugs for guttate psoriasis. There is also a need for studies that clearly distinguish the specific population with guttate psoriasis from the larger group of people with chronic plaque psoriasis, and children and young adults should be assessed as a distinct group.

Completeness of Descriptions of Repetitive Transcranial Magnetic Stimulation Intervention: A Systematic Review of Randomized Controlled Trials of rTMS in Depression.

OBJECTIVES: Repetitive transcranial magnetic stimulation (rTMS) is an innovative therapeutic option in major depressive disorder (MDD). A complete description of the procedure in reports of randomized controlled trials (RCTs) is a prerequisite for implementation of rTMS in clinical practice. The aim of this study was to evaluate the completeness of descriptions of the intervention in RCTs assessing rTMS in MDD. METHODS: We performed a systematic review of RCTs evaluating rTMS in MDD and published until August 2016. We searched PubMed, the Cochrane library, and PsycINFO to identify eligible trials. The completeness of the intervention description was evaluated by the use of an adapted-to-rTMS version of the Template for Intervention Description and Replication (TIDieR) checklist. We defined core items that are the most essential to be reported. Missing information was then sought from additional sources and by e-mailing authors. RESULTS: We identified 98 trials reporting 134 interventions. None of the interventions were completely described in the full text of the articles, even after searching additional sources. After contacting the authors, 14 (10.4%) of 134 interventions were completely described. The core items were completely described in 74 (55.2%) of 134 interventions after contacting the authors. CONCLUSIONS: We found that rTMS interventions delivered in RCTs are incompletely reported, which prevents their adequate implementation in clinical practice and accurate interpretation of their efficacy. We encourage authors, editors, and reviewers to use the existing reporting guidelines and specifically the TIDieR checklist when describing the intervention. We provide an adapted-to-rTMS TIDieR checklist that could help in the reporting of future trials.

Ventilator-Free Day Outcomes Can Be Misleading.

INTRODUCTION: Acute respiratory distress syndrome often requires invasive mechanical ventilation, with both mortality and mechanical ventilation duration as outcomes of interest. The concept of ventilator-free days has been proposed as an outcome combining these two outcomes. Here we analyzed the construction of the ventilator-free day outcome and provided a hypothetical scenario to alert physicians that such an outcome can lead to misleading interpretations. METHODS: We proposed the isoventilator-free day curve concept and, using an analytical development, illustrated how a median ventilator-free day value can actually result from very different combinations of death rates and mechanical ventilation durations. We also used a hypothetical example to compare the Student t test, Wilcoxon rank-sum test, and Gray test (which accounts for death as a competing event with extubation) in comparing exposition to mechanical ventilation. RESULTS: A median ventilator-free day value of 10 days may mean that 10% of the patients died while survivors were ventilated during a median of 14 days or that 40% died while survivors were ventilated during a median of 5 days. Changing the time horizon affected the Student t test but not the Wilcoxon rank-sum result. The Gray test was more relevant than both the Student t test and Wilcoxon rank-sum test in identifying differences in groups showing highly different mechanical ventilation duration, despite equal median ventilator-free days. This approach was also illustrated using real data. CONCLUSIONS: Use of ventilator-free days as an outcome appears to have many drawbacks. Suitable methods of analyzing time to extubation should be preferred.

Sleep and mood changes in advanced age after blue-blocking (yellow) intra ocular lens (IOLs) implantation during cataract surgical treatment: a randomized controlled trial.

OBJECTIVES: Both advanced age and depression are characterized by changes in sleep patterns. Light exposure is one of the main synchronizers of circadian cycles and influences sleep by inhibiting melatonin secretion, which is mostly sensitive to light of low wavelengths (blue). Blue-blocking (yellow) intraocular lenses (IOLs) have supplanted the usual UV-blocking (clear) IOLs during cataract surgery to prevent age-related macular degeneration, however, the impact of yellow IOLs on sleep and mood is unclear. The purpose of this study was to compare the effects of yellow and clear IOLs on sleep and mood in aged patients undergoing bilateral cataract surgery. METHODS: A randomized controlled superiority study was conducted within three ophthalmic surgical wards in France. A total of 204 subjects (mean age 76.2 ± 7.5 years) were randomized into yellow or clear IOLs groups. Patients completed a sleep diary, the pictorial sleepiness scale and the Beck Depression Inventory (BDI) one week before and eight weeks after the last surgical procedure. RESULTS: According to an Intent To Treat (ITT) analysis, no significant difference was found between yellow and clear IOLs groups regarding sleep time, sleep latency, total sleep duration, quality of sleep and BDI scores. The rate of patients whose BDI score increased at the cutoff score of ≥5 after surgery was significantly higher in the yellow IOL group (n = 11, 13.1%) compared with the clear IOL group (n = 4; 4.7%); p = 0.02. CONCLUSIONS: Using yellow IOLs for cataract surgery doesn't significantly impact sleep but may induce mood changes in aging.

Sample size calculation for meta-epidemiological studies.

Meta-epidemiological studies are used to compare treatment effect estimates between randomized clinical trials with and without a characteristic of interest. To our knowledge, there is presently nothing to help researchers to a priori specify the required number of meta-analyses to be included in a meta-epidemiological study. We derived a theoretical power function and sample size formula in the framework of a hierarchical model that allows for variation in the impact of the characteristic between trials within a meta-analysis and between meta-analyses. A simulation study revealed that the theoretical function overestimated power (because of the assumption of equal weights for each trial within and between meta-analyses). We also propose a simulation approach that allows for relaxing the constraints used in the theoretical approach and is more accurate. We illustrate that the two variables that mostly influence power are the number of trials per meta-analysis and the proportion of trials with the characteristic of interest. We derived a closed-form power function and sample size formula for estimating the impact of trial characteristics in meta-epidemiological studies. Our analytical results can be used as a 'rule of thumb' for sample size calculation for a meta-epidemiologic study. A more accurate sample size can be derived with a simulation study.

Efficacy and Safety of Mammalian Target of Rapamycin Inhibitors in Vascular Anomalies: A Systematic Review.

Mammalian target of rapamycin (mTOR) inhibitors are a promising new treatment in vascular anomalies, but no published randomized controlled trials are available. The aim of this systematic review of all reported cases was to assess the efficacy and safety of mTOR inhibitors in all vascular anomalies, except cancers, in children and adults. In November 2014 MEDLINE, CENTRAL, LILACS and EMBASE were searched for studies of mTOR inhibitors in any vascular condition, except for malignant lesions, in humans. Fourteen publications and 9 posters, with data on 25 and 59 patients, respectively, all < 18 years old were included. Of these patients, 35.7% (n = 30) had vascular tumours, and 64.3% (n = 54) had malformations. Sirolimus was the most frequent mTOR inhibitor used (98.8%, n = 83). It was efficient in all cases, at a median time of 2 weeks (95% confidence interval 1-10 weeks). Sirolimus was well tolerated, the main side-effect being mouth sores, which led to treatment withdrawal in one case. The dosage of sirolimus was heterogeneous, the most common being 1.6 mg/m2/day.