Incidence of pulmonary embolism in non-critically ill COVID-19 patients. Predicting factors for a challenging diagnosis.

Recent studies suggest that thrombotic complications are a common phenomenon in the novel SARS-CoV-2 infection. The main objective of our study is to assess cumulative incidence of pulmonary embolism (PE) in non critically ill COVID-19 patients and to identify its predicting factors associated to the diagnosis of pulmonary embolism. We retrospectevely reviewed 452 electronic medical records of patients admitted to Internal Medicine Department of a secondary hospital in Madrid during Covid 19 pandemic outbreak. We included 91 patients who underwent a multidetector Computed Tomography pulmonary angiography(CTPA) during conventional hospitalization. The cumulative incidence of PE was assessed ant the clinical, analytical and radiological characteristics were compared between patients with and without PE. PE incidence was 6.4% (29/452 patients). Most patients with a confirmed diagnosed with PE recieved low molecular weight heparin (LMWH): 79.3% (23/29). D-dimer peak was significatly elevated in PE vs non PE patients (14,480 vs 7230 mcg/dL, p = 0.03). In multivariate analysis of patients who underwent a CTPA we found that plasma D-dimer peak was an independen predictor of PE with a best cut off point of > 5000 µg/dl (OR 3.77; IC95% (1.18-12.16), p = 0.03). We found ninefold increased risk of PE patients not suffering from dyslipidemia (OR 9.06; IC95% (1.88-43.60). Predictive value of AUC for ROC is 75.5%. We found a high incidence of PE in non critically ill hospitalized COVID 19 patients despite standard thromboprophylaxis. An increase in D-dimer levels is an independent predictor for PE, with a best cut-off point of > 5000 µg/ dl.

Validity of estimated aortic pulse wave velocity measured during the 6-min walk test to predict anaerobic fitness before major non-cardiac surgery.

BACKGROUND: This study aimed to assess the efficacy of estimated preoperative aortic pulse wave velocity (AoPWV) to discriminate between low and high 6 min walk test (6MWT) distance in patients awaiting major non-cardiac surgery. METHODS: Prospective observational study in 133 patients undergoing non cardiac surgery. AoPWV and the distance walked during a 6MWT were assessed. Receiver operating characteristic (ROC) curve analysis was used to determine two different AoPWV cut-points for predicting a distance of 427 m in the 6MWT. We also calculated lower and upper AoPWV cut-points (probability ≥ 0.75) for predicting a distance of < 427 m, ≥427 m, and also 563 m in the 6MWT. RESULTS: The ROC curve analysis for the < 427 m distance revealed an area under the curve (AUC) of 0.68 (95% confidence interval 0.56-0.79) and an AUC of 0.72 (95% confidence interval 0.61-0.83) for >563 m. Patients with AoPWV > 10.97 m/s should be considered high risk, while those with <9.42 m/s can be considered low risk. CONCLUSIONS: AoPWV is a simple, non-invasive, useful clinical tool for identifying and stratifying patients awaiting major non-cardiac surgery. In situations of clinical uncertainty, additional measures should be taken to assess the risk.

Intraoperative goal-directed hemodynamic therapy through fluid administration to optimize the stroke volume: A meta-analysis of randomized controlled trials.

OBJECTIVE: To evaluate the clinical impact of optimizing stroke volume (SV) through fluid administration as part of goal-directed hemodynamic therapy (GDHT) in adult patients undergoing elective major abdominal surgery. METHODS: This systematic review and meta-analysis was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement and was registered in the PROSPERO database in January 2024. The intervention was defined as intraoperative GDHT based on the optimization or maximization of SV through fluid challenges, or by using dynamic indices of fluid responsiveness, including stroke volume variation, pulse pressure variation, and plethysmography variation index compared to usual fluid management. The primary outcome was postoperative complications. Secondary outcome variables included postoperative acute kidney injury (AKI), length of stay (LOS), intraoperative fluid administration, and 30-day mortality. RESULTS: A total of 29 randomized controlled trials (RCTs) met the inclusion criteria. There were no significant differences in the incidence of postoperative complications (RR 0.89; 95% CI, 0.78-1.00), postoperative AKI (OR 0.97; (95% IC, 0.55-1.70), and mortality (OR 0.80; 95% CI, 0.50-1.29). GDHT was associated with a reduced LOS compared to usual care (SMD: -0.17 [-0.32; -0.03]). The subgroup in which hydroxyethyl starch was used for hemodynamic optimization was associated with fewer complications (RR 0.79; 95% CI, 0.65-0.94), whereas the subgroup of patients in whom crystalloids were used was associated with an increased risk of postoperative complications (RR 1.08; 95% CI, 1.04-1.12). CONCLUSIONS: In adults undergoing major surgery, goal-directed hemodynamic therapy focused on fluid-based stroke volume optimization did not reduce postoperative morbidity and mortality.

Management of peri-surgical anemia in elective surgery. Conclusions and recommendations according to Delphi-UCLA methodology.

INTRODUCTION: Preoperative anemia affects approximately one third of surgical patients. It increases the risk of blood transfusion and influences short- and medium-term functional outcomes, increases comorbidities, complications and costs. The "Patient Blood Management" (PBM) programs, for integrated and multidisciplinary management of patients, are considered as paradigms of quality care and have as one of the fundamental objectives to correct perioperative anemia. PBM has been incorporated into the schemes for intensified recovery of surgical patients: the recent Enhanced Recovery After Surgery 2021 pathway (in Spanish RICA 2021) includes almost 30 indirect recommendations for PBM. OBJECTIVE: To make a consensus document with RAND/UCLA Delphi methodology to increase the penetration and priority of the RICA 2021 recommendations on PBM in daily clinical practice. MATERIAL AND METHODS: A coordinating group composed of 6 specialists from Hematology-Hemotherapy, Anesthesiology and Internal Medicine with expertise in anemia and PBM was formed. A survey was elaborated using Delphi RAND/UCLA methodology to reach a consensus on the key areas and priority professional actions to be developed at the present time to improve the management of perioperative anemia. The survey questions were extracted from the PBM recommendations contained in the RICA 2021 pathway. The development of the electronic survey (Google Platform) and the management of the responses was the responsibility of an expert in quality of care and clinical safety. Participants were selected by invitation from speakers at AWGE-GIEMSA scientific meetings and national representatives of PBM-related working groups (Seville Document, SEDAR HTF section and RICA 2021 pathway participants). In the first round of the survey, the anonymized online questionnaire had 28 questions: 20 of them were about PBM concepts included in ERAS guidelines (2 about general PBM organization, 10 on diagnosis and treatment of preoperative anemia, 3 on management of postoperative anemia, 5 on transfusion criteria) and 8 on pending aspects of research. Responses were organized according to a 10-point Likter scale (0: strongly disagree to 10: strongly agree). Any additional contributions that the participants considered appropriate were allowed. They were considered consensual because all the questions obtained an average score of more than 9 points, except one (question 14). The second round of the survey consisted of 37 questions, resulting from the reformulation of the questions of the first round and the incorporation of the participants' comments. It consisted of 2 questions about general organization of PBM programme, 15 questions on the diagnosis and treatment of preoperative anemia; 3 on the management of postoperative anemia, 6 on transfusional criteria and finally 11 questions on aspects pending od future investigations. Statistical treatment: tabulation of mean, median and interquartiles 25-75 of the value of each survey question (Tables 1, 2 and 3). RESULTS: Except for one, all the recommendations were accepted. Except for three, all above 8, and most with an average score of 9 or higher. They are grouped into: 1.- "It is important and necessary to detect and etiologically diagnose any preoperative anemia state in ALL patients who are candidates for surgical procedures with potential bleeding risk, including pregnant patients". 2.- "The preoperative treatment of anemia should be initiated sufficiently in advance and with all the necessary hematinic contributions to correct this condition". 3.- "There is NO justification for transfusing any unit of packed red blood cells preoperatively in stable patients with moderate anemia Hb 8-10g/dL who are candidates for potentially bleeding surgery that cannot be delayed." 4.- "It is recommended to universalize restrictive criteria for red blood cell transfusion in surgical and obstetric patients." 5.- "Postoperative anemia should be treated to improve postoperative results and accelerate postoperative recovery in the short and medium term". CONCLUSIONS: There was a large consensus, with maximum acceptance,strong level of evidence and high recommendation in most of the questions asked. Our work helps to identify initiatives and performances who can be suitables for the implementation of PBM programs at each hospital and for all patients.

Association between preoperative baseline pulse pressure and estimated pulse wave velocity and acute renal failure and mortality following colorectal surgery. A single-centre observational study. / Asociación entre la presión de pulso y la velocidad onda pulso estimada basal preoperatoria con las complicaciones postoperatorias, insuficiencia renal aguda y mortalidad tras cirugía colorrectal. Estudio unicéntrico observacional.

BACKGROUND: Elevated pulse wave velocity is a haemodynamic parameter considered to be a risk factor for the development of cardiovascular alterations, while pulse pressure is a predictor of cardiovascular complications and development of acute renal failure after both cardiac and non-cardiac surgery. Our objective was to determine whether baseline pulse pressure and estimated pulse wave velocity are associated with renal failure and 30-day mortality following colorectal surgery. METHODS: Retrospective observational study. A total of 816 adult patients undergoing elective colorectal surgery were evaluated by performing multivariable logistic regression analysis to determine whether baseline pulse pressure and estimated pulse wave velocity were independently associated with complications, specifically renal failure and 30-day postoperative mortality, and whether pulse pressure and estimated pulse wave velocity thresholds correlated with outcomes. RESULTS: Baseline pulse pressure was 56.00mmHg (45.00;68.00) and estimated pulse wave velocity was 13.16m/s (10.76;14.85). Baseline pulse pressure was not associated with acute renal failure or mortality in the univariate model. Baseline estimated pulse wave velocity was not associated with complications, acute renal failure, or mortality. An estimated pulse wave velocity of 13.78m/s significantly predicted acute renal failure (AUC 0.654 [0.588-0.720]) and mortality (AUC 0.698 [0.600-0.796]). CONCLUSIONS: Neither pulse pressure nor preoperative baseline estimated pulse wave velocity were associated with acute renal failure or postoperative mortality. The preoperative estimated pulse wave velocity threshold of 13.78m/s predicted an increased risk of acute renal failure and postoperative mortality.

Association between preoperative baseline pulse pressure and estimated pulse wave velocity and acute renal failure and mortality following colorectal surgery. A single-centre observational study.

BACKGROUND: Elevated pulse wave velocity is a haemodynamic parameter considered to be a risk factor for the development of cardiovascular alterations, while pulse pressure is a predictor of cardiovascular complications and development of acute renal failure after both cardiac and non-cardiac surgery. Our objective was to determine whether baseline pulse pressure and estimated pulse wave velocity are associated with renal failure and 30-day mortality following colorectal surgery. METHODS: Retrospective observational study. A total of 816 adult patients undergoing elective colorectal surgery were evaluated by performing multivariable logistic regression analysis to determine whether baseline pulse pressure and estimated pulse wave velocity were independently associated with complications, specifically renal failure and 30-day postoperative mortality, and whether pulse pressure and estimated pulse wave velocity thresholds correlated with outcomes. RESULTS: Baseline pulse pressure was 56.00 mmHg (45.00;68.00) and estimated pulse wave velocity was 13.16 m/s (10.76;14.85). Baseline pulse pressure was not associated with acute renal failure or mortality in the univariate model. Baseline estimated pulse wave velocity was not associated with complications, acute renal failure, or mortality. An estimated pulse wave velocity of 13.78 m/s significantly predicted acute renal failure (AUC 0.654 [0.588-0.720]) and mortality (AUC 0.698 [0.600-0.796]). CONCLUSIONS: Neither pulse pressure nor preoperative baseline estimated pulse wave velocity were associated with acute renal failure or postoperative mortality. The preoperative estimated pulse wave velocity threshold of 13.78 m/s predicted an increased risk of acute renal failure and postoperative mortality.

Intraoperative crystalloid utilization variability and association with postoperative outcomes: A post hoc analysis of two multicenter prospective cohort studies.

BACKGROUND: The optimal regimen for intravenous administration of intraoperative fluids remains unclear. Our goal was to analyze intraoperative crystalloid volume administration practices and their association with postoperative outcomes. METHODS: We extracted clinical data from two multicenter observational studies including adult patients undergoing colorectal surgery and total hip (THA) and knee arthroplasty (TKA). We analyzed the distribution of intraoperative fluid administration. Regression was performed using a general linear model to determine factors predictive of fluid administration. Patient outcomes and intraoperative crystalloid utilization were summarized for each surgical cohort. Regression models were developed to evaluate associations of high or low intraoperative crystalloid with the likelihood of increased postoperative complications, mainly acute kidney injury (AKI) and hospital length of stay (LOS). RESULTS: 7580 patients were included. The average adjusted intraoperative crystalloid infusion rate across all surgeries was to 7.9 (SD 4) mL/kg/h. The regression model strongly favored the type of surgery over other patient predictors. We found that high fluid volume was associated with 40% greater odds ratio (OR 1.40; 95% confidence interval 1.01-1.95, p = 0.044) of postoperative complications in patients undergoing THA, while we found no associations for the other types of surgeries, AKI and LOS CONCLUSIONS: A wide variability was observed in intraoperative crystalloid volume administration; however, this did not affect postoperative outcomes.

[Transcranial Doppler ultrasound, bispectral index, and electroencephalographic monitoring of entropy during sevoflurane anesthesia in children]. / Doppler transcraneal, BIS y entropía como medición indirecta del flujo cerebral durante la anestesia inhalatoria en pacientes pediátricos.

BACKGROUND AND OBJECTIVE: Transcranial Doppler ultrasound is a noninvasive technique for monitoring the velocity of blood flow in the main intracranial arteries, particularly those in the circle of Willis. Our aim was to assess whether changes in cerebral arterial blood flow in pediatric patients under sevoflurane anesthesia demonstrated by pulsed Doppler ultrasound correlate with changes in the bispectral (BIS) index and electroencephalographic state and response entropy (ES and ER, respectively). MATERIAL AND METHODS: Prospective, blinded observational study of 36 pediatric patients (age range, 5 to 11 years; ASA physical status classification, 1-2) under sevoflurane anesthesia for minor surgical procedures. Anesthesia was induced with sevoflurane and maintained with 2.5% sevoflurane in an inspired oxygen fraction of 50% in air. A continuous perfusion of remifentanil was provided for analgesia. In all patients we monitored hemodynamic and respiratory patterns, gases, temperature, and hypnosis (BIS, ES and ER) as well as cerebral blood flow estimated by pulsed Doppler ultrasound in the middle cerebral artery. The resistance index, pulsatility index, mean velocity, and estimated baseline cerebral blood flow were calculated from the Doppler sonogram. Correlations (Pearson's r) were calculated between BIS, ES, ER, the pulsatility index, resistance index, mean flow velocity, estimated cerebral blood flow, fraction of end-tidal carbon dioxide, and temperature. A regression model was constructed. RESULTS: Induction caused a pattern of high velocity (elevated mean velocity and normal or reduced pulsatility index) until the lowest BIS and ES values of 31 and 29, respectively, were reached. During maintenance, the Doppler sonogram pattern was slower (normalization of the pulsatility index, the resistance index, and mean velocity). Changes in flow and absolute entropy and BIS values were statistically correlated (Pearson's r values > or = 0.91); there was 95.6% agreement between Doppler values and BIS and agreement between BIS and ES values of 35 to 45. On awakening, flow velocities approached baseline values when BIS and ES rose to between 90 and 98. The estimated cerebral blood flow underwent fluctuations coinciding with an approximately concomitant increase or decrease in BIS (r > 0.95); the BIS response occurred with a slight delay of no more than a minute. The entropy measurements did not reflect the fluctuations. CONCLUSIONS: We show Doppler ultrasound patterns during anesthetic induction with sevoflurane. Systems for monitoring hypnosis could be considered indirect measurements of cerebral blood flow; BIS measurements are more sensitive to change. Transcranial Doppler ultrasound facilitates the observation of changes in blood flow that occur at different levels of hypnosis during anesthesia.

Postoperative Outcomes Within an Enhanced Recovery after surgery protocol in gastric surgery for cancer (POWER.4): Study protocol for a prospective, multicentre, observational cohort study. / Auditoría nacional de complicaciones después de la cirugía gástrica por cáncer dentro o no de un protocolo de recuperación intensificada (POWER.4): Protocolo de un estudio prospectivo, multicéntrico, observacional de cohortes.

BACKGROUND AND OBJECTIVE: Enhanced recovery pathways or ERAS have been applied in gastric cancer surgery extrapolated from colorectal surgery. The objective of the study is to assess postoperative complications 30 days after gastric surgery for cancer, with any level of compliance with the ERAS protocol. The secondary objectives are to assess 30-day mortality, the relationship between adherence to the ERAS protocol and complications, the impact of each of the items of the protocol on postoperative complications and hospital stay, and to describe the impact of complications on length of hospital stay. MATERIALS AND METHODS: Multicenter, observational, prospective study including all consecutive patients undergoing scheduled gastric cancer surgery, over a period of 3 months, with a 30-day follow-up at participating centers, with any level of compliance with the protocol. RESULTS: The approval of the Comité Autonómico de Ética de la Investigación de Aragón has been obtained (C.P. - C.I. PI19 / 106, 27 th March 2019). POWER.4 was registered at www.clinicaltrials.gov on March 7, 2019 (NCT03865810). CONCLUSIONS: The data as a whole will be published in peer-reviewed journals. The data will not be made public by identifying each participating center. It is expected that the results of this study will identify potential areas for improvement in which more targeted research is needed.

Patient Blood Management for primary hip and knee replacement. A survey among POWER.2 study researchers. / Patient Blood Management en artroplastia primaria de cadera y rodilla. Encuesta entre los investigadores del estudio POWER.2.

BACKGROUND: Implementation of Patient Blood Management programs remain variable in Europe, and even in centres with well-established PBM programs variability exists in transfusion practices. OBJECTIVES AND METHODS: We conducted a survey in order to assess current practice in perioperative Patient Blood Management in patients undergoing total hip and knee replacement among researchers involved in POWER.2 Study in Spain (an observational prospective study evaluating enhanced recovery pathways in orthopaedic surgery). RESULTS: A total of 322 responses were obtained (37.8%). Half of responders check Haemoglobin levels in patients at least 4 weeks before surgery; 35% treat all anaemic patients, although 99.7% consider detection and treatment of preoperative anaemia could influence the postoperative outcomes. Lack of infrastructure (76%) and lack of time (51%) are the main stated reasons not to treat anaemic patients. Iron status is routinely checked by 19% before surgery, and 36% evaluate it solely in the anaemic patient. Hb<9.9 g/dl is the threshold to delay surgery for 61% of clinicians, and 22% would consider transfusing preoperatively clinically stable patients without active bleeding. The threshold to transfuse patients without cardiovascular disease is 8 g/dl for 43%, and 7 g/dl for 34% of the responders; 75% of clinicians consider they use "restrictive thresholds", and 90% follow the single unit transfusion policy. CONCLUSIONS: The results of our survey show variability in clinical practice in Patient Blood Management in major orthopaedic surgery, despite being the surgery with the greatest tradition in these programs.

Patient Blood Management en artroplastia primaria de cadera y rodilla. Encuesta entre los investigadores del estudio POWER.2 / Patient Blood Management for primary hip and knee replacement. A survey among POWER.2 study researchers

ANTECEDENTES: La implementación de los programas Patient Blood Management (PBM) es variable en Europa, incluso en centros en los que estos programas están bien establecidos, donde existe variabilidad en cuanto a prácticas transfusionales. OBJETIVOS Y MÉTODOS: Realizamos una encuesta para valorar la práctica actual sobre PBM perioperatoria en pacientes programados para artroplastia total de cadera y rodilla, entre los investigadores involucrados en el Estudio POWER.2 en España (estudio observacional prospectivo que evaluaba las vías de recuperación intensificada en cirugía ortopédica). RESULTADOS: Se obtuvo un total de 322 respuestas (37,8%). El 50% de los respondedores revisaban los niveles de hemoglobina, al menos 4 semanas antes de la cirugía; el 35% trataba a todos los pacientes anémicos, aunque el 99,7% consideraba que la detección y tratamiento de la anemia preoperatoria podrían influir en los resultados postoperatorios. La falta de infraestructuras (76%) y la falta de tiempo (51%) fueron los principales motivos para no tratar a los pacientes anémicos. El estatus del hierro es revisado antes de la cirugía por el 19% de manera rutinaria, y el 36% lo evalúa únicamente en pacientes anémicos. Hb<9,9g/dl es el valor umbral para demorar la cirugía para el 61% de los clínicos, y el 22% consideraría transfundir preoperatoriamente a los pacientes clínicamente estables sin sangrado activo. El valor umbral para transfundir a los pacientes sin enfermedad cardiovascular es 8g/dl para el 43% y 7g/dl para el 34% de los respondedores; el 75% de los facultativos considera que utiliza «umbrales restrictivos», y el 90% sigue la política transfusional uno a uno (single unit). CONCLUSIONES: Los resultados de nuestra encuesta muestran la variabilidad en la práctica clínica en PBM en cirugía ortopédica mayor, a pesar de ser el tipo de cirugía con más tradición en estos programas

BACKGROUND: Implementation of Patient Blood Management programs remain variable in Europe, and even in centres with well-established PBM programs variability exists in transfusion practices. OBJECTIBES AND METHODS: We conducted a survey in order to assess current practice in perioperative Patient Blood Management in patients undergoing total hip and knee replacement among researchers involved in POWER.2 Study in Spain (an observational prospective study evaluating enhanced recovery pathways in orthopaedic surgery). RESULTS: A total of 322 responses were obtained (37.8%). Half of responders check Haemoglobin levels in patients at least 4 weeks before surgery; 35% treat all anaemic patients, although 99.7% consider detection and treatment of preoperative anaemia could influence the postoperative outcomes. Lack of infrastructure (76%) and lack of time (51%) are the main stated reasons not to treat anaemic patients. Iron status is routinely checked by 19% before surgery, and 36% evaluate it solely in the anaemic patient. Hb<9.9 g/dl is the threshold to delay surgery for 61% of clinicians, and 22% would consider transfusing preoperatively clinically stable patients without active bleeding. The threshold to transfuse patients without cardiovascular disease is 8 g/dl for 43%, and 7 g/dl for 34% of the responders; 75% of clinicians consider they use "restrictive thresholds", and 90% follow the single unit transfusion policy. CONCLUSIONS: The results of our survey show variability in clinical practice in Patient Blood Management in major orthopaedic surgery, despite being the surgery with the greatest tradition in these programs

Auditoría nacional de complicaciones después de la cirugía gástrica por cáncer dentro o no de un protocolo de recuperación intensificada (POWER.4): Protocolo de un estudio prospectivo, multicéntrico, observacional de cohortes / Postoperative Outcomes Within an Enhanced Recovery after surgery protocol in gastric surgery for cancer (POWER.4): Study protocol for a prospective, multicentre, observational cohort study

ANTECEDENTES Y OBJETIVO: Los protocolos de recuperación intensificada o ERAS se han aplicado en cirugía de cáncer gástrico extrapolados desde la cirugía colorrectal. El objetivo del estudio es evaluar la incidencia de complicaciones postoperatorias a los 30 días de la cirugía de resección gástrica por cáncer, con cualquier nivel de cumplimiento del protocolo ERAS. Los objetivos secundarios son evaluar la mortalidad a 30 días, la relación entre la adherencia al protocolo ERAS y las complicaciones, el impacto de cada uno de los ítems del protocolo en las complicaciones postoperatorias y en la estancia hospitalaria, y describir el efecto de las complicaciones postoperatorias en la duración de la estancia hospitalaria. MATERIALES Y MÉTODOS: Estudio multicéntrico, observacional, prospectivo que incluirá todos los pacientes consecutivos que vayan a ser tratados mediante cirugía de cáncer gástrico programada, durante un periodo de 3 meses, con un seguimiento de 30 días en los centros participantes, con cualquier nivel de cumplimiento del protocolo. RESULTADOS: Se ha obtenido la aprobación del Comité Autonómico de Ética de la Investigación de Aragón (C.P.-C.I. PI19/106, del 27 de marzo del 2019). POWER.4 fue registrado en www.clinicaltrials.gov el 7 de marzo del 2019 (NCT03865810). CONCLUSIONES: Los datos en conjunto serán publicados en revistas con revisión por pares. No se harán públicos los datos identificando cada centro participante. Se espera que los resultados de este estudio permitirán identificar áreas potenciales de mejora en las que se necesite realizar una investigación más dirigida

BACKGROUND AND OBJECTIVE: Enhanced recovery pathways or ERAS have been applied in gastric cancer surgery extrapolated from colorectal surgery. The objective of the study is to assess postoperative complications 30 days after gastric surgery for cancer, with any level of compliance with the ERAS protocol. The secondary objectives are to assess 30-day mortality, the relationship between adherence to the ERAS protocol and complications, the impact of each of the items of the protocol on postoperative complications and hospital stay, and to describe the impact of complications on length of hospital stay. MATERIALS AND METHODS: Multicenter, observational, prospective study including all consecutive patients undergoing scheduled gastric cancer surgery, over a period of 3 months, with a 30-day follow-up at participating centers, with any level of compliance with the protocol. RESULTS: The approval of the Comité Autonómico de Ética de la Investigación de Aragón has been obtained (C.P. - C.I. PI19 / 106, 27 th March 2019). POWER.4 was registered at www.clinicaltrials.gov on March 7, 2019 (NCT03865810). CONCLUSIONS: The data as a whole will be published in peer-reviewed journals. The data will not be made public by identifying each participating center. It is expected that the results of this study will identify potential areas for improvement in which more targeted research is needed