Short-term outcomes of a multicentre prospective study using a "visible" polyvinylidene fluoride onlay mesh for the prevention of midline incisional hernia.

INTRODUCTION: Prophylactic meshes in high-risk patients prevent incisional hernias, although there are still some concerns about the best layer to place them in, the type of fixation, the mesh material, the significance of the level of contamination, and surgical complications. We aimed to provide answers to these questions and information about how the implanted material behaves based on its visibility under magnetic resonance imaging (MRI). METHOD: This is a prospective multicentre observational cohort study. Preliminary results from the first 3 months are presented. We included general surgical patients who had at least two risk factors for developing an incisional hernia. Multivariate logistic regression was used. A polyvinylidene fluoride (PVDF) mesh loaded with iron particles was used in an onlay position. MRIs were performed 6 weeks after treatment. RESULTS: Between July 2016 and June 2022, 185 patients were enrolled in the study. Surgery was emergent in 30.3% of cases, contaminated in 10.7% and dirty in 11.8%. A total of 5.6% of cases had postoperative wound infections, with the requirement of stoma being the only significant risk factor (OR = 7.59, p = 0.03). The formation of a seroma at 6 weeks detected by MRI, was associated with body mass index (OR = 1.13, p = 0.02). CONCLUSIONS: The prophylactic use of onlay PVDF mesh in midline laparotomies in high-risk patients was safe and effective in the short term, regardless of the type of surgery or the level of contamination. MRI allowed us to detect asymptomatic seromas during the early process of integration. STUDY REGISTRATION:  This protocol was registered at ClinicalTrials.gov (NCT03105895).

The Role and Versatility of the Temporoparietal Fascia Flap for Coverage of Cochlear Implant Extrusion.

The use of cochlear implants (CI) may be associated with different complications, being extrusion of the device one of the most common. Reconstruction of the defect with a healthy and vascularized tissue is often required. We present two patients with a CI extrusion treated with a temporoparietal fascia flap.

Timing jitter reduction in semiconductor lasers induced by optical injection.

We present an experimental study of the effect of continuous-wave optical injection (OI) from a vertical-cavity surface-emitting laser (VCSEL) on the timing jitter of a gain-switched discrete-mode semiconductor laser (DML). Timing jitter was analyzed over a wide range of temperatures of the DML, which allowed tuning the detuning between the lasers emissions, and it was compared with the inter-pulse timing jitter. We have found that there is a range of detunings in which OI diminishes the jitter by 70% with respect to the jitter of the solitary DML. However, within this region, there are some detunings for which OI significantly increases the jitter.

Experimental study of spatial and temporal coherence in a laser diode with optical feedback.

Optical feedback can reduce the linewidth of a semiconductor laser by several orders of magnitude, but it can also cause line broadening. Although these effects on the temporal coherence of the laser are well known, a good understanding of the effects of feedback on the spatial coherence is still lacking. Here we present an experimental technique that allows discriminating the effects of feedback on temporal and spatial coherence of the laser beam. We analyze the output of a commercial edge-emitting laser diode, comparing the contrast of speckle images recorded using a multimode (MM) or single mode (SM) fiber and an optical diffuser, and also, comparing the optical spectra at the end of the MM or SM fiber. Optical spectra reveal feedback-induced line broadening, while speckle analyses reveal reduced spatial coherence due to feedback-excited spatial modes. These modes reduce the speckle contrast (SC) up to 50% when speckle images are recorded using the MM fiber, but do not affect the SC when the images are recorded using the SM fiber and diffuser, because the spatial modes that are excited by the feedback are filtered out by the SM fiber. This technique is generic and can be used to discriminate spatial and temporal coherence of other types of lasers and under other operating conditions that can induce a chaotic output.

Abrupt transition from low-coherence to high-coherence radiation in a semiconductor laser with optical feedback.

Semiconductor lasers are very sensitive to optical feedback. Although it is well known that coherent feedback lowers the threshold of the laser, the characteristics of the transition from low-coherence radiation-dominated by spontaneous emission-below threshold to high-coherence radiation-dominated by stimulated emission-above threshold have not yet been investigated. Here we show experimentally that, in contrast to the transition that occurs in the solitary laser, in the laser with feedback the transition to high-coherence emission can occur abruptly. We use the speckle technique to show that the transition varies from smooth to abrupt as the amount of light fed back to the laser increases.

Prophylactic use of incisional negative pressure wound therapy for the prevention of surgical site occurrences in general surgery: Consensus document.

BACKGROUND: Surgical site occurrences pose a threat to patient health, potentially resulting in significant increases in health care spending caused by using additional resources. The objective of this study was to reach a consensus among a group of experts in incisional negative pressure wound therapy to determine the indications for using this type of treatment prophylactically and to analyze the associated risk factors of surgical site occurrences in abdominal surgery. METHODS: A group of experts in incisional negative pressure wound therapy from Spain and Portugal was formed among general surgery specialists who frequently perform colorectal, esophagogastric, or abdominal wall surgery. The Coordinating Committee performed a bibliographic search to identify the most relevant publications and to create a summary table to serve as a decision-making protocol regarding the use of prophylactic incisional negative pressure wound therapy based on factors related to the patient and type of procedure. RESULTS: The patient risk factors associated with surgical site occurrence development such as age, immunosuppression, anticoagulation, hypoalbuminemia, smoking, American Society of Anesthesiologists classification, diabetes, obesity, and malnutrition were analyzed. For surgical procedure factors, surgical time, repeated surgeries, organ transplantation, need for blood transfusion, complex abdominal wall reconstruction, surgery at a contaminated site, open abdomen closure, emergency surgery, and hyperthermic intraperitoneal chemotherapy were analyzed. CONCLUSION: In our experience, this consensus has been achieved on a tailored set of recommendations on patient and surgical aspects that should be considered to reduce the risk of surgical site occurrences with the use of prophylactic incisional negative pressure wound therapy, particularly in areas where the evidence base is controversial or lacking.

Age and Breast Reconstruction.

BACKGROUND: Breast reconstruction is frequently offered to cancer patients who undergo mastectomy. Older women tend to have lower rates of reconstruction mostly due to an age-based discretion. We aimed to assess the safety of this surgery in this population. METHODS: We conducted a single-center retrospective analysis of patients who underwent breast reconstruction following mastectomy between 2015 and 2020 at "Complejo Hospitalario Universitario de Albacete." Patients were classified according to age when the reconstruction process began (group A: < 65 years-group B: > 65 years). Differences in demographics and clinical data were analyzed using Student's t test and Chi-square test. Multivariable logistic regression models were used to estimate odds ratio (OR) and confidence intervals (CIs) for surgical complications according to age group. Propensity-score matching was used as a sensitivity analysis to test consistency among results. RESULTS: We included 304 women (266: group A-38: group B). Complete reconstruction was achieved in 48.1% of patients in group A vs 10.5% in group B (P < 0.001). After adjusting for potential confounders, age was not associated with an increased risk of surgical complications, neither overall (OR 0.88, 95%CI 0.40-1.95), early (OR 1.35, 95%CI 0.58-3.13) nor late (OR 1.05, 95%CI 0.40-2.81). Radiotherapy and smoking history were significant predictors for complications in every setting. CONCLUSIONS: In our cohort, age at breast reconstruction is not associated with a higher risk of surgical complications, in contrast to radiotherapy and smoking history. Therefore, age should not be a limiting factor when considering breast reconstruction. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Evaluación económica del tratamiento quirúrgico de la obesidad / Economic evaluation of surgical treatment of obesity

INTRODUCCIÓN: La cirugía bariátrica es el mejor tratamiento de la obesidad mórbida a largo plazo. El ahorro generado por la mejoría de las comorbilidades podría justificar el empleo de más recursos sanitarios. MÉTODOS: Estudio observacional, descriptivo, longitudinal y retrospectivo, de pacientes a los que se les realizó un bypass gástrico, en el Hospital Universitario Central de Asturias entre 2003 y 2012. El seguimiento mínimo se estableció en dos años. Calculamos de manera individualizada el coste para cada uno de los pacientes intervenidos (bottom-up), así como según el grupo relacionado por el diagnóstico (GRD) (top-down). RESULTADOS: De los 307 pacientes del estudio, el coste medio del ingreso calculado por GRD fue de 6.545,9€ y el calculado por paciente de 10.572,2€. El GRD 288 representa al 91% de la serie con un valor de 4.631€. El cálculo estimativo del ahorro que supuso en nuestro entorno sanitario la disminución del número de fármacos de 2,86 a 0,78 por paciente medicado, representó 4.433€ por paciente intervenido si padecía todas las comorbilidades analizadas. CONCLUSIONES: El bypass gástrico en el Hospital Universitario Central de Asturias a los dos años de la cirugía, en pacientes con pluripatología consiguió un ahorro solo en fármacos que podría compensar los gastos inherentes al tratamiento quirúrgico. El coste por proceso mediante GRD se mostró insuficiente a la hora de hacer una correcta evaluación económica, por lo que recomendamos un método de evaluación de coste por paciente

INTRODUCTION: Obesity surgery is the best treatment for extreme obesity, with demonstrated long-term positive outcomes. The potential cost-savings generated by the improvement of comorbidities after surgery can justify the allocation of more resources in the surgical treatment of obesity. METHODS: This was an observational, descriptive, longitudinal and retrospective study. Eligible patients underwent Roux-en-Y gastric bypass surgery at the Hospital Universitario Central de Asturias between 2003 and 2012. The established minimum follow-up period was two years. We calculated the individualized cost per patient treated (bottom-up) as well as per Diagnosis-Related Group (DRG) codes (top-down). RESULTS: Our study included 307 patients. The average cost per hospitalization calculated by DRG codes was €6,545.90, and the average cost per patient was €10,572.20. DRG 288 represented 91% of the series, with a value of €4,631. The number of medications also decreased during this period, from 2.86 to 0.78 per medically treated patient, representing a cost reduction of €4,433 per patient with all the obesity-related comorbidities analyzed. CONCLUSIONS: Two years after Roux-en-Y gastric bypass conducted at Hospital Universitario Central de Asturias, the savings in drug costs for patients with multiple pathologies would compensate the inherent costs of the surgical treatment itself. Our results showed that DRG-related costs was insufficient to make a correct economic evaluation, so we recommend an individualized cost calculating method

Use of Symmetry Assessment Methods in the Context of Breast Surgery.

BACKGROUND: Different procedures are available to help clinicians evaluate symmetry and cosmetic results in an objective manner after conservative breast cancer surgery. However, there are no similar methods in esthetic breast surgery, where the subjective assessment of the surgeon or the patient is usually considered the gold standard. The aim of this study is to evaluate the application of four software programs in the context of esthetic breast surgery and contrast their results with those of the subjective evaluation by a series of healthcare professionals. MATERIALS AND METHODS: Sixty cosmetic breast surgery images were studied using four software programs considered appropriate for the objective evaluation (BCCT3.core®, Breast Analyzing Tool®, Objective Breast Cosmesis Scale® and GBAI-Global Breast Asymmetry Index®). The same cases were assessed by a group of 100 health professionals through an online survey as a subjective evaluation method. RESULTS: Concordance among participants was high (κ = 0.753) as well as between three of the objective methods (BSI, OBCS, GBAI), but not with the BCCT parameter. There was no association between objective and subjective methods studied by the survey, according to the logistic regression model. The "symmetry" and "asymmetry" categories were accurately distinguished by the objective methods. CONCLUSIONS: Objective evaluation in esthetic breast surgery has less variability than subjective assessment, and the estimation is possible through certain software previously restricted to conservative breast cancer surgery. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Prospective Analysis Regarding Health-Related Quality of Life (HR-QOL) between Morbid Obese Patients Following Bariatric Surgery Versus on a Waiting List.

BACKGROUND: Major impairment of health-related quality of life (HRQoL) is one of the main reasons why obese patients request surgical treatment. OBJECTIVE: To prospectively analyze the impact of HRQoL between obese patients who underwent surgery and those who were wait-listed. METHODS: Between April 2017 and March 2018, 70 surgical and 69 wait-listed patients were interviewed twice, at baseline and at the 12-month follow-up. Quality of life was measured by the SF-12v2 and the Impact of Weight on Quality of Life-Lite (IWQoL-Lite) questionnaires. Sociodemographic-, clinical-, and surgical-related variables were collected. RESULTS: One hundred thirty-nine patients were analyzed, showing similar baseline characteristics but differences in HRQoL. Performing more qualified work improved scores on some aspects of the SF-12 survey. In contrast, women scored worse on the self-esteem domain, and men scored worse on the mental health domain. By group, at the 12-month follow-up, statistically significant differences were found among all aspects of the questionnaires between both groups (P < 0.001) and between baseline and postoperative 12-month follow-up in the surgical group (P < 0.001). Furthermore, scores were lower in all domains in the evolution of wait-listed patients, with statistically significant differences among the Bodily Pain, Emotional Role, Mental Health, and Mental Component Summary Domains (P < 0.05). CONCLUSION: HRQoL is a multimodal concept that allows the identification of factors impacting obese patients' quality of life. It promotes the benefit of surgery against waiting list delays, which can take up to 4 years in our hospital. Therefore, HRQoL is an important pillar to justify more resources for reducing unacceptable surgical delays.

Economic evaluation of surgical treatment of obesity. / Evaluación económica del tratamiento quirúrgico de la obesidad.

INTRODUCTION: Obesity surgery is the best treatment for extreme obesity, with demonstrated long-term positive outcomes. The potential cost-savings generated by the improvement of comorbidities after surgery can justify the allocation of more resources in the surgical treatment of obesity. METHODS: This was an observational, descriptive, longitudinal and retrospective study. Eligible patients underwent Roux-en-Y gastric bypass surgery at the Hospital Universitario Central de Asturias between 2003 and 2012. The established minimum follow-up period was two years. We calculated the individualized cost per patient treated (bottom-up) as well as per Diagnosis-Related Group (DRG) codes (top-down). RESULTS: Our study included 307 patients. The average cost per hospitalization calculated by DRG codes was €6,545.90, and the average cost per patient was €10,572.20. DRG 288 represented 91% of the series, with a value of €4,631. The number of medications also decreased during this period, from 2.86 to 0.78 per medically treated patient, representing a cost reduction of €4,433 per patient with all the obesity-related comorbidities analyzed. CONCLUSIONS: Two years after Roux-en-Y gastric bypass conducted at Hospital Universitario Central de Asturias, the savings in drug costs for patients with multiple pathologies would compensate the inherent costs of the surgical treatment itself. Our results showed that DRG-related costs was insufficient to make a correct economic evaluation, so we recommend an individualized cost calculating method.

Evidencia en seguimiento y pronóstico del cáncer de unión esofagogástrica / Evidence in follow-up and prognosis of esophagogastric junction cancer

La supervivencia a cinco años de los tumores de la unión esofagogástrica está en el 50% en los estadios más favorables y con los tratamientos coadyuvantes más eficaces. Más del 40% de los pacientes sufrirá recurrencias en un periodo breve, habitualmente en el primer año tras una cirugía potencialmente curativa y la supervivencia tras esa recurrencia suele ser menor de 6 meses, pues el tratamiento es poco eficaz, sea quimioterapia paliativa, radioterapia o exéresis quirúrgica de las recidivas únicas. El tipo y frecuencia del seguimiento realizado influye en la supervivencia porque la detección de recurrencias asintomáticas permite realizar tratamientos más precoces y efectivos

Five-year survival of tumors of the esophagogastric junction is 50%, in the most favourable stages and with the most effective adjuvant treatments. More than 40% of patients will have recurrences within a short period, usually the first year after potentially curative surgery. Survival after this recurrence is usually less than 6 months because treatment is not very effective, be it palliative chemotherapy, radiotherapy or surgical excision of single recurrences. As the detection of asymptomatic recurrences allows for earlier and more effective treatments to be used, the type and frequency of follow-up has an influence on survival

Evidence in follow-up and prognosis of esophagogastric junction cancer. / Evidencia en seguimiento y pronóstico del cáncer de unión esofagogástrica.

Five-year survival of tumors of the esophagogastric junction is 50%, in the most favourable stages and with the most effective adjuvant treatments. More than 40% of patients will have recurrences within a short period, usually the first year after potentially curative surgery. Survival after this recurrence is usually less than 6 months because treatment is not very effective, be it palliative chemotherapy, radiotherapy or surgical excision of single recurrences. As the detection of asymptomatic recurrences allows for earlier and more effective treatments to be used, the type and frequency of follow-up has an influence on survival.

Laparoscopic treatment of large bowel obstruction due to a self-locating peritoneal dialysis catheter.

INTRODUCTION: Peritoneal dialysis has been used in the treatment of end-stage renal disease for a long time. The development of continuous ambulatory peritoneal dialysis (CAPD) has achieved an acceptable device of renal replacement therapy. PRESENTATION OF CASE: We report a 55 year-old patient who was initiated on CAPD in February 2016. Three months later, the Tenckhoff catheter was removed due to its malfunction, and a new self-locating peritoneal dialysis catheter was placed in the left side of the abdomen. In September 2016, the patient presented with symptoms of intestinal obstruction. A CT scan revealed a collapsed sigmoid colon with the tungsten tip of the catheter supported on the mesosigmoid as the cause of the occlusion. DISCUSSION: Herein, a rare but clinically important case of mechanical large bowel obstruction due to self-locating peritoneal dialysis catheter is presented. The weight added to the tip of the self-locating catheter for the purpose of stretching it, can be dangerous if a displacement takes place. A laparoscopic procedure was performed, resolving the obstruction by reinserting the peritoneal catheter in its right position. CONCLUSION: The weight added to the tip of self-locating catheters is a matter of concern, since intimate contact between the peritoneal catheter and the intestinal wall can result in perforation or intestinal occlusion.