Individualised perioperative blood pressure and fluid therapy in oesophagectomy ­ study protocol for a randomised clinical trial

INTRODUCTION: Oesophagectomy is the mainstay of curative treatment for oesophageal cancer, but it is associated with a high risk of major complications. Goal-directed fluid therapy and individualised blood pressure management may prevent complications after surgery. Extending goal-directed fluid therapy after surgery and applying an individual blood pressure target may have substantial benefit in oesophagectomy. This is a protocol for a clinical trial implementing a novel haemodynamic protocol from the start of anaesthesia to the next day with the patient's own night-time blood pressure as the lower threshold. METHODS: This is a single-centre, single-blind, randomised, clinical trial. Oesophagectomy patients are randomised 1:1 for either perioperative haemodynamic management according to a goal-directed fluid therapy protocol with an individual target blood pressure or for standard care. The primary endpoint is the total burden of morbidity and mortality assessed by the Comprehensive Complication Index 30 days after surgery. Secondary endpoints are complications, reoperations, fluid and vasopressor dosage and quality of life at 90 days after surgery. CONCLUSIONS: The results from this trial provide an objective and easy-to-follow algorithm for fluid administration, which may improve patient-centred outcomes in oesophagectomy patients. FUNDING: The trial is supported by Aarhus University (1,293,400 DKK) and the Novo Nordisk Foundation (625,200 DKK). TRIAL REGISTRATION: EudraCT number: 2021-002816-30.

[The management of gastric polyps].

This review summarizes the work-up and treatment of gastric polyps. Fundic gland polyps can be identified macroscopically, and they generally bear no malignancy potential. Hyperplastic polyps and adenomas require histology to be diagnosed. Adenomas should always be resected, whereas resection of hyperplastic polyps is recommended if they bear atypical features. Eradication of concomitant Helicobacter pylori is recommended as it may causes regression of the polyp(s). Standardized biopsies from the surrounding mucosa should be taken on the smallest indication. The discovery of adenomas or dysplasia calls for a one-year followup.

Local Pressure Drives Low-Density Lipoprotein Accumulation and Coronary Atherosclerosis in Hypertensive Minipigs.

BACKGROUND: The mechanisms by which hypertension accelerates coronary artery disease are poorly understood. Patients with hypertension often have confounding humoral changes, and to date, no experimental models have allowed analysis of the isolated effect of pressure on atherosclerosis in a setting that recapitulates the dimensions and biomechanics of human coronary arteries. OBJECTIVES: This study sought to analyze the effect of pressure on coronary atherosclerosis and explore the underlying mechanisms. METHODS: Using inflatable suprarenal aortic cuffs, we increased mean arterial pressure by >30 mm Hg in the cephalad body part of wild-type and hypercholesterolemic proprotein convertase subtilisin kexin type 9 (PCSK9)D374Y Yucatan minipigs for >1 year. Caudal pressures remained normal. RESULTS: Under hypercholesterolemic conditions in PCSK9D374Y transgenic minipigs, cephalad hypertension accelerated coronary atherosclerosis to almost 5-fold with consistent development of fibroatheromas that were sufficiently large to cause stenosis on computed tomography angiography. This was caused by local pressure forces, because vascular beds shielded from hypertension, but exposed to the same humoral factors, showed no changes in lesion formation. The same experiment was conducted under normocholesterolemic conditions in wild-type minipigs to examine the underlying mechanisms. Hypertension produced clear changes in the arterial proteome with increased abundance of mechanical strength proteins and reduced levels of infiltrating plasma macromolecules. This was paralleled by increased smooth muscle cells and increased intimal accumulation of low-density lipoproteins in the coronary arteries. CONCLUSIONS: Increased pressure per se facilitates coronary atherosclerosis. Our data indicate that restructuring of the artery to match increased tensile forces in hypertension alters the passage of macromolecules and leads to increased intimal accumulation of low-density lipoproteins.

Internal gallbladder drainage prevents development of acute cholecystitis in a pig model: a randomized study.

BACKGROUND: Acute cholecystitis can be the result of retention of bile in the gallbladder with possible secondary infection and ischaemia. The aim of the present study was to investigate whether internal drainage of the gallbladder could protect against the development of acute cholecystitis in a pig model. MATERIALS AND METHODS: Twenty pigs were randomized to either internal drainage (drained) or not (undrained). Day 0 acute cholecystitis was induced by ligation of the cystic artery and duct together with inoculation of bacteria. Four days later the pigs were killed and the gallbladders were removed and histologically scored for the presence of cholecystitis. Bile and blood samples were collected for bacterial culturing and biochemical analyses. RESULTS: The histological examination demonstrated statistical significant differences in acute cholecystitis development between groups, the degree of inflammation being highest in undrained pigs. There were no differences in bacterial cultures between the two groups. CONCLUSION: Internal drainage of the gallbladder protected against the development of acute cholecystitis in the present pig model. These findings support the theory that gallstone impaction of the cystic duct plays a crucial role as a pathogenetic mechanism in the development of acute cholecystitis and suggest that internal drainage may be a way to prevent and treat acute cholecystitis.

Reversibility of central neuronal changes in patients recovering from gallbladder stones or acute cholecystitis.

AIM: To investigate the referred pain area in patients 2-7 years after cholecystectomy in order to test the hypothesis that neuroplastic changes could give rise to post cholecystectomy pain. METHODS: Forty patients were tested. Twenty five were cholecystectomized due to uncomplicated gallbladder stones and 15 because of acute cholecystitis. Sensitivity to pinprick, heat, cold, pressure and single and repeated electrical stimulation was studied both in the referred pain area and in the control area on the contra lateral side of the abdomen. RESULTS: Five patients still intermittently suffered from pain. But in the objective test of the 40 patients, no statistical significant difference was found between the referred pain area and the control area. CONCLUSION: This study does not support the hypothesis that de novo neuroplastic changes could develop several years after cholecys-tectomy.