Search

Background and aim: Erector spinae plane (ESP) block is a regional anesthesia technique recently described, that has gained growing interest because of its relative safety, versatility and simplicity, when compared to other approaches, including paravertebral block (PVB). In the context of thoracic surgery, clinical trials are needed to evaluate the potential efficacy of this new technique. This clinical trial aims to test the non-inferiority of ESP block compared to PVB, in patients with early-stage lung cancer admitted to a tertiary referral center for elective pulmonary lobectomy, under video-assisted thoracic surgery (VATS). Design: Randomized, controlled, single-blinded, non-inferiority clinical trial. Participants: Patients aging between 18 and 85 years old, diagnosed of early-stage non-small cell lung cancer, and admitted for elective VATS lobectomy. Measurements and procedures: All participants will be blinded to the intervention. After undergoing general anesthesia, they will receive either ESP block or PVB, according to their randomized allocation. The primary outcome will be pain intensity at 30 minutes after the operation, which will be measured by an 11-point (0 to 10) Visual Analogue Scale (VAS). Secondary outcomes will include VAS score at 30 min and at 6, 12 and 24 hours after arrival to the recovery area, morphine consumption at 24 hours, time of performance of the block, and complications related to the procedure. Ethical aspects: For the development of this protocol, all ethical principles outlined in the last version of the Declaration of Helsinki (Fortaleza, Brazil, 2013) have been followed. Approval from local ethical committee and written informed consent from all participants will be obtained. Keywords: Thoracic surgery video-assisted, non-small-cell lung carcinoma, anesthesia recovery period, pain management. Abbreviations: ANOVA Analysis of Variance, DMC Data Monitoring Committee, ESP Erector Spinae Plane, MAR Missing At Random, MCAR Missing Completely At random, PVB Paravertebral Block, PCA Patient-controlled Analgesia, TEA Thoracic Epidural Analgesia, VAS Visual Analogue Scale, VATS Video-Assisted Thoracic Surgery.

Background and Aim: Diabetic macular edema (DME) is one of the leading causes of visual impairment among working-aged people responsible for more than 10,000 new cases of blindness per year. Although there are some therapeutical options for this disease, most of them are invasive, expensive, subject to a range of side effects, and may not be accessible to the entire population. In addition, conventional eye drops are not able to adequately deliver the drug to the posterior chamber of the eye, where DME develops. In this setting, it has been suggested that topical dexamethasone-cyclodextrin microparticle eye drop (TDCME) formulation may be effective in treating DME. The aim of this manuscript is to describe a study protocol for evaluating the efficacy of this formulation, compared with intravitreal injection of ranibizumab. Design: Phase II, randomized, double-dummy, multicenter, controlled, non-inferiority clinical trial. Participants: Adults aged >18 year-old, diagnosed with controlled diabetes (type I or II), and refractory moderate to severe DME in at least one eye at the beginning of study. Measurements and procedures: Participants will be allocated to either the intervention or control group using block randomization, through a centralized off-site computer interactive response system. The treatment group will receive sham intravitreal injections plus TDCME, whereas the control group will receive intravitreal injection of ranibizumab (0.5 mg) plus Endura TM (artificial tears eye drops emulsion, used as placebo). While injections will be performed every month, eye drops will be given three times a day (every 8 hours). The primary efficacy outcome will be the change in best corrected visual acuity (BCVA) between baseline and at the end of the 12-month-follow-up time. Ethical aspects: This trial will be carried out according to the tenants of the Declaration of Helsinki and other international guidelines. Participants will be required to provide informed written consent prior to enrolling in the study. A Data Safety Monitoring Board will be established to follow the study.

Postoperative vision loss following a major spine operation is a rare but life-changing event. Most of reports have been linked to ischemic optic neuropathy, and patients undergoing surgery for scoliosis correction or posterior lumbar fusion seem to be at the highest risk. Despite that some key risk factors have been identified, much of the pathophysiology still remain unknown. In fact, whereas only a minority of patients at high risk will present this complication, others with similar risk factors undergoing different procedures may not develop it at all. On the other hand, even when all preventive measures have been taken, ischemic optic neuropathy may still occur. Therefore, it is appropriate for clinicians involved in these cases to inform their patients about the existence of a small but unpredictable risk of vision loss. Since ischemic optic neuropathy is deemed to be the leading cause of vision loss in the context of major spine surgery in prone position, this review will be focused on its main aspects related to the frequency, diagnosis, predisposing factors, and prevention. Regrettably, no treatment has been proved to be effective for this condition.

The process of formulating a good research question can be challenging and frustrating. While a comprehensive literature review is compulsory, the researcher usually encounters methodological difficulties in the conduct of the study, particularly if the primary study question has not been adequately selected in accordance with the clinical dilemma that needs to be addressed. Therefore, optimising time and resources before embarking in the design of a clinical protocol can make an impact on the final results of the research project. Researchers have developed effective ways to convey the message of how to build a good research question that can be easily recalled under the acronyms of PICOT (population, intervention, comparator, outcome, and time frame) and FINER (feasible, interesting, novel, ethical, and relevant). In line with these concepts, this article highlights the main issues faced by clinicians, when developing a research question.

In this narrative review, the current evidence for the use of mannitol in neuroanaesthesia is presented, with focus on its pharmacokinetics and its main physiologic effects. Mannitol is a naturally occurring polyol that undergoes no biotransformation and is freely filtered in the kidney. Due to its strong osmotic effects, it induces key physiological changes, mainly in the cardiovascular system, the kidney and the brain. While it is clear that hypertonic solutions are effective in the treatment of intracranial hypertension in patients with acute brain injury, the role of mannitol in the context of intracranial haemorrhage, acute stroke and brain relaxation remains controversial. Furthermore, it possesses important side effects including acute kidney injury and electrolyte imbalances, particularly related to high doses in predisposing patients. Other aspects including the capability to modify neurological outcomes, the impact on mortality, the utility in patients with disrupted blood–brain barrier and the alternative use of hypertonic saline are also discussed. Further research is needed to make clear recommendations on these aspects.