Gastrointestinal Transit Times in Health as Determined Using Ingestible Capsule Systems: A Systematic Review.

BACKGROUND: Ingestible capsule (IC) systems can assess gastrointestinal (GI) transit times as a surrogate for gut motility for extended periods of time within a minimally invasive, radiation-free and ambulatory setting. METHODS: A literature review of IC systems and a systematic review of studies utilizing IC systems to measure GI transit times in healthy volunteers was performed. Screening for eligible studies, data extraction and bias assessments was performed by two reviewers. A narrative synthesis of the results was performed. RESULTS: The literature review identified 23 different IC systems. The systematic review found 6892 records, of which 22 studies were eligible. GI transit time data were available from a total of 1885 healthy volunteers. Overall, seventeen included studies reported gastric emptying time (GET) and small intestinal transit time (SITT). Colonic transit time (CTT) was reported in nine studies and whole gut transit time (WGTT) was reported in eleven studies. GI transit times in the included studies ranged between 0.4 and 15.3 h for GET, 3.3-7 h for SITT, 15.9-28.9 h for CTT and 23.0-37.4 h for WGTT. GI transit times, notably GET, were influenced by the study protocol. CONCLUSIONS: This review provides an up-to-date overview of IC systems and reference ranges for GI transit times. It also highlights the need to standardise protocols to differentiate between normal and pathological function

Laparoscopic surgery for elective abdominal aortic aneurysm repair

Background: Abdominal aortic aneurysm (AAA) is an abnormal dilatation of the infradiaphragmatic aorta that is equal to or greater than 30 mm or a local dilatation of equal to or greater than 50% compared to the expected normal diameter of the artery. AAAs rarely occur in individuals under 50 years of age, but thereafter the prevalence dramatically increases with age, with men at a six-fold greater risk of developing an AAA than women. Prevalence of AAA has been reported to range from 1.3% in women aged 65 to 80 years to between 4% and 7.7% in men aged 65 to 80 years. There is evidence that the risk of rupture increases as the aneurysm diameter increases from 50 mm to 60 mm. People with AAAs over 55 mm in diameter are therefore generally referred for consideration of repair, as the risk of rupture exceeds the risk of repair. The traditional treatment for AAA is open surgical repair (OSR) which involves a large abdominal incision and is associated with a significant risk of complications. Two less invasive procedures have recently become more widely used: endovascular aneurysm repair (EVAR) and laparoscopic repair. EVAR is carried out through sheaths inserted in the femoral artery in the groin: thereafter, a stent graft is placed within the aneurysm sac under radiological image guidance and anchored in place to form a new channel for blood flow. Laparoscopic repair involves the use of a laparoscope which is inserted through small cuts in the abdomen and the synthetic graft is sewn in place to replace the weakened area of the aorta. Laparoscopic AAA repair falls into two categories: hand-assisted laparoscopic surgery (HALS), where an incision is made to allow the surgeon's hand to assist in the repair; and total laparoscopic surgery (TLS). Both EVAR and laparoscopic repair are favourable over OSR as they are minimally invasive, less painful, associated with fewer complications and lower mortality rate and have a shorter duration of hospital stay. Current evidence suggests that elective laparoscopic AAA repair has a favourable safety profile comparable with that of EVAR, with low conversion rates as well as similar mortality and morbidity rates. As a result, it has been suggested that elective laparoscopic AAA repair may have a role in treating those patients for whom EVAR is unsuitable. Objectives: To assess the effects of laparoscopic surgery for elective abdominal aortic aneurysm repair. The primary objective of this review was to assess the perioperative mortality and operative time of laparoscopic (total and hand-assisted) surgical repair of abdominal aortic aneurysms (AAA) compared to traditional open surgical repair or EVAR. The secondary objective was to assess complication rates, all-cause mortality (> 30 days), hospital and intensive care unit (ICU) length of stay, conversion and re-intervention rates, and quality of life associated with laparoscopic (total and hand-assisted) surgical repair compared to traditional open surgical repair or EVAR. Search methods: The Cochrane Vascular Information Specialist (CIS) searched the Specialised Register (last searched August 2016) and CENTRAL (2016, Issue 7). In addition the CIS searched trials registries for details of ongoing or unpublished studies. We searched the reference lists of relevant articles retrieved by electronic searches for additional citations. Selection criteria: Randomised controlled trials and controlled clinical trials in which patients with an AAA underwent elective laparoscopic repair (total laparoscopic repair or hand-assisted laparoscopic repair) compared with either open surgical repair or EVAR. Data collection and analysis: Studies identified for potential inclusion were independently assessed for inclusion by at least two review authors. Main results: One randomised controlled trial with a total of 100 male participants was included in the review. The trial compared hand-assisted laparoscopic repair with EVAR and provided results for in-hospital mortality, operative time, length of hospital stay and lower limb ischaemia. The included study did not report on the other pre-planned outcomes of this review. No in-hospital deaths occurred in the study. Hand-associated laparoscopic repair was associated with a longer operative time (MD 53.00 minutes, 95% CI 36.49 to 69.51) than EVAR. The incidence of lower limb ischaemia was similar between the two treatment groups (risk ratio (RR) 0.50, 95% confidence interval (CI) 0.05 to 5.34). The mean length of hospital stay was 4.2 days and 3.4 days in the hand-assisted laparoscopic repair and EVAR groups respectively but standard deviations were not reported and therefore it was not possible to independently test the statistical significance of this result. The quality of evidence was downgraded for imprecision due to the inclusion of one small study; and wide confidence intervals and indirectness due to the study including male participants only. No study compared laparoscopic repair (total or hand-assisted) with open surgical repair or total laparoscopic surgical repair with EVAR. Authors' conclusions: There is insufficient evidence to draw any conclusions about effectiveness and safety of laparoscopic (total and hand-assisted) surgical repair of AAA versus open surgical repair or EVAR, because only one small randomised trial was eligible for inclusion in this review. High-quality randomised controlled trials are needed

Evaluating pharmacological THRomboprophylaxis in Individuals undergoing superficial endoVEnous treatment across NHS and private clinics in the UK: a multi-centre, assessor-blind, randomised controlled trial - THRIVE trial

\ua9 Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY. Published by BMJ.Introduction Endovenous therapy is the first choice management for symptomatic varicose veins in NICE guidelines, with 56-70 000 procedures performed annually in the UK. Venous thromboembolism (VTE), including deep vein thrombosis (DVT) and pulmonary embolism (PE), is a known complication of endovenous therapy, occurring at a rate of up to 3.4%. Despite 73% of UK practitioners administering pharmacological thromboprophylaxis to reduce VTE, no high-quality evidence supporting this practice exists. Pharmacological thromboprophylaxis may have clinical and cost benefit in preventing VTE; however, further evidence is needed. This study aims to establish whether when endovenous therapy is undertaken: a single dose or course of pharmacological thromboprophylaxis alters the risk of VTE; pharmacological thromboprophylaxis is associated with an increased rate of bleeding events; pharmacological prophylaxis is cost effective. Methods and analysis A multi-centre, assessor-blind, randomised controlled trial (RCT) will recruit 6660 participants from 40 NHS and private sites across the UK. Participants will be randomised to intervention (single dose or extended course of pharmacological thromboprophylaxis plus compression) or control (compression alone). Participants will undergo a lower limb venous duplex ultrasound scan at 21-28 days post-procedure to identify asymptomatic DVT. The duplex scan will be conducted locally by blinded assessors. Participants will be contacted remotely for follow-up at 7 days and 90 days post-procedure. The primary outcome is imaging-confirmed lower limb DVT with or without symptoms or PE with symptoms within 90 days of treatment. The main analysis will be according to the intention-to-treat principle and will compare the rates of VTE at 90 days, using a repeated measures analysis of variance, adjusting for any pre-specified strongly prognostic baseline covariates using a mixed effects logistic regression. Ethics and dissemination Ethical approval was granted by Brent Research Ethics Committee (22/LO/0261). Results will be disseminated in a peer-reviewed journal and presented at national and international conferences. Trial registration number ISRCTN18501431

Electron impact ionization of water-doped superfluid helium nanodroplets: Observation of He(H2O)n+ clusters

Electron impact mass spectra have been recorded for helium nanodroplets containing water clusters. In addition to identification of both H+(H2O)n and (H2O)n+ ions in the gas phase, additional peaks are observed which are assigned to He(H2O)n+ clusters for up to n = 27. No clusters are detected with more than one helium atom attached. The interpretation of these findings is that quenching of (H2O)n+ by the surrounding helium can cool the cluster to the point where not only is fragmentation to H+(H2O)m (where m ⩽ n−1) avoided, but also, in some cases, a helium atom can remain attached to the cluster ion as it escapes into the gas phase. Ab initio calculations suggest that the first step after ionization is the rapid formation of distinct H3O+ and OH units within the (H2O)n+ cluster. To explain the formation and survival of He(H2O)n+ clusters through to detection, the H3O+ is assumed to be located at the surface of the cluster with a dangling O–H bond to which a single helium atom can attach via a charge-induced dipole interaction. This study suggests that, like H+(H2O)n ions, the preferential location for the positive charge in large (H2O)n+ clusters is on the surface rather than as a solvated ion in the interior of the cluster

Preoperative anaemia management in patients undergoing vascular surgery.

CAVIAR is a multicentre prospective stepped observational study encompassing 160 patients undergoing vascular intervention. The aim was to identify whether it was feasible to establish a preoperative anaemia pathway and, if so, the efficacy of intravenous iron for treatment of preoperative anaemia. Large barriers prevented implementation of an intravenous iron pathway, with only ten patients receiving intravenous iron and a small increase in haemoglobin level (mean 5·7 (95 per cent c.i. 4·5 to 6·9) g/l). Preoperative anaemia was associated with a longer hospital stay and greater transfusion requirement

The Impact of Pre-Operative Anaemia on One Year Amputation Free Survival and Re-Admissions in Patients Undergoing Vascular Surgery for Peripheral Arterial Disease: a National Vascular Registry Study

OBJECTIVE: Anaemia is common among patients undergoing surgery, but its association with post-operative outcomes in patients with peripheral arterial disease (PAD) is unclear. The aim of this observational population based study was to examine the association between pre-operative anaemia and one year outcomes after surgical revascularisation for PAD. METHODS: This study used data from the National Vascular Registry, linked with an administrative database (Hospital Episode Statistics), to identify patients who underwent open surgical lower limb revascularisation for PAD in English NHS hospitals between January 2016 and December 2019. The primary outcome was one year amputation free survival. Secondary outcomes were one year re-admission rate, 30 day re-intervention rate, 30 day ipsilateral major amputation rate and 30 day death. Flexible parametric survival analysis and generalised linear regression were performed to assess the effect of anaemia on one year outcomes. RESULTS: The analysis included 13 641 patients, 57.9% of whom had no anaemia, 23.8% mild, and 18.3% moderate or severe anaemia. At one year follow up, 80.6% of patients were alive and amputation free. The risk of one year amputation or death was elevated in patients with mild anaemia (adjusted HR 1.3; 95% CI 1.15 - 1.41) and moderate or severe anaemia (aHR 1.5; 1.33 - 1.67). Patients with moderate or severe anaemia experienced more re-admissions over one year (adjusted IRR 1.31; 1.26 - 1.37) and had higher odds of 30 day re-interventions (aOR 1.22; 1.04 - 1.45), 30 day ipsilateral major amputation (aOR 1.53; 1.17 - 2.01), and 30 day death (aOR 1.39; 1.03 - 1.88) compared with patients with no anaemia. CONCLUSION: Pre-operative anaemia is associated with lower one year amputation free survival and higher one year re-admission rates following surgical revascularisation in patients with PAD. Research is required to evaluate whether interventions to correct anaemia improve outcomes after lower limb revascularisation

Evaluating the feasibility and acceptability of an exercise and behaviour change intervention in socioeconomically deprived patients with peripheral arterial disease: The textpad study protocol

This pilot randomised controlled trial aims to assess the feasibility and acceptability of a 12-week home-based telehealth exercise and behavioural intervention delivered in socioeconomically deprived patients with peripheral artery disease (PAD). The study will also determine the preliminary effectiveness of the intervention for improving clinical and health outcomes. Sixty patients with PAD who meet the inclusion criteria will be recruited from outpatient clinic at the Freeman Hospital, United Kingdom. The intervention group will undergo telehealth behaviour intervention performed 3 times per week over 3 months. This program will comprise a home-based exercise (twice a week) and an individual lifestyle program (once per week). The control group will receive general health recommendations and advice to perform unsupervised walking training. The primary outcome will be feasibility and acceptability outcomes. The secondary outcomes will be objective and subjective function capacity, quality of life, dietary quality, physical activity levels, sleep pattern, alcohol and tobacco use, mental wellbeing, and patients’ activation. This pilot study will provide preliminary evidence of the feasibility, acceptability and effectiveness of home-based telehealth exercise and behavioural intervention delivered in socioeconomically deprived patients with PAD. In addition, the variance of the key health outcomes of this pilot study will be used to inform the sample size calculation for a future fully powered, multicentre randomized clinical trial

Groin wound infection after vascular exposure ( GIVE ) multicentre cohort study

Surgical site infections (SSIs) of groin wounds are a common and potentially preventable cause of morbidity, mortality, and healthcare costs in vascular surgery. Our aim was to define the contemporaneous rate of groin SSIs, determine clinical sequelae, and identify risk factors for SSI. An international multicentre prospective observational cohort study of consecutive patients undergoing groin incision for femoral vessel access in vascular surgery was undertaken over 3 months, follow‐up was 90 days. The primary outcome was the incidence of groin wound SSI. 1337 groin incisions (1039 patients) from 37 centres were included. 115 groin incisions (8.6%) developed SSI, of which 62 (4.6%) were superficial. Patients who developed an SSI had a significantly longer length of hospital stay (6 versus 5 days, P = .005), a significantly higher rate of post‐operative acute kidney injury (19.6% versus 11.7%, P = .018), with no significant difference in 90‐day mortality. Female sex, Body mass index≥30 kg/m2, ischaemic heart disease, aqueous betadine skin preparation, bypass/patch use (vein, xenograft, or prosthetic), and increased operative time were independent predictors of SSI. Groin infections, which are clinically apparent to the treating vascular unit, are frequent and their development carries significant clinical sequelae. Risk factors include modifiable and non‐modifiable variables