Long-term outcome of cervical artery dissection.

OBJECTIVE: The aim of the study is to evaluate the natural history of extracranial cervical artery dissection (CAD) including comorbidities, symptoms at presentation, recurrence of symptoms, and long-term outcome following different treatment approaches. METHODS: A retrospective review of patients treated for acute CAD was performed over a 5-year period from January 2017 to April 2022. RESULTS: Thirty-nine patients were included in the study, 25 (64.1%) with acute internal carotid artery dissection and 14 (35.9%) with acute vertebral artery dissection. Thirty-four patients (87.1%) had spontaneous CAD, and five patients (12.8%) had traumatic CAD. The mean age of the cohort was 54.2 years. The mean time from symptom onset to presentation was 4.34 days. The most common symptoms in internal carotid artery dissection were unilateral weakness (44%), headache (44%), slurred speech (36%), facial droop (28%), unilateral paraesthesia (24%), neck pain (12%), visual disturbance (8%), and Horner's syndrome (8%). The most common symptoms in vertebral artery dissection were headache (35.7%), neck pain (35.7%), vertigo (28.57%), ataxia (14.28%), and slurred speech (14.28%). The imaging modalities used for diagnosis included computed tomography angiography (48.7%), magnetic resonance angiography (41%), and duplex ultrasound (10.2%). In patients with carotid artery dissection, 57% had severe stenosis, 24% had moderate stenosis, and 20% had mild stenosis. All patients treated were managed conservatively with either anticoagulation or antiplatelets. Long-term clinical follow-up was available for 33 patients (84.6%). Thirty patients (90.9%) reported complete resolution of symptoms, and three patients (9%) reported persistent symptoms. Anatomic follow-up with imaging was available for 17 patients (43.58%). Thirteen patients (76.47%) had complete resolution of dissection, two patients (11.76%) had partial resolution of dissection, and two patients (11.76%) had persistent dissection. There was one death unrelated to CAD in a multi-trauma patient. There were four early recurrent symptoms in the first 3 to 8 weeks post discharge. The mean follow-up time was 308.27 days. CONCLUSIONS: The majority of CADs can be managed conservatively with good clinical and anatomical outcome and low rates of recurrence.

Transient iatrogenic Horner's syndrome following carotid endarterectomy.

We present a case of a 72-year-old man who developed a transient Horner's syndrome in the immediate postoperative period after right carotid endarterectomy which resolved within 3 months. Although Horner's syndrome has been reported with several disorders of the carotid artery, our case documents a rare iatrogenic oculosympathetic paresis after elective carotid endarterectomy.

End-To-Side versus Side-To-Side Anastomosis in Upper Limb Arteriovenous Fistula for Dialysis Access: A Systematic Review and a Meta-Analysis.

BACKGROUND: An arteriovenous fistula (AVF) is the best modality for hemodialysis access. The end-to-side (ETS) technique has been suggested in the literature to produce superior results to the side-to-side (STS) approach; however, in the absence of a systematic review, this practice remains debatable. METHODS: Online search for randomized controlled trials and observational studies that compared the ETS versus the STS anastomosis techniques in creating an upper limb AVF. Aims were to systematically assess the difference between both procedures in terms of access maturation, patency, and postoperative complications. RESULTS: Seven studies were included with 463 patients in the ETS group and 523 in the STS group. The difference between the 2 techniques was not significant in relation to patency rates at 3, 6, 12, and 24 months (P values: 0.28, 0.82, 0.54, and 0.21, respectively). There were fewer cases of postoperative hematoma in the ETS group; however, the difference was not significant (P = 0.09). Arterial steal syndrome was found to be significantly associated with the STS configuration in pooled analysis (pooled risk ratio = 0.11 [0.01-0.88], 95% CI, P = 0.04). CONCLUSIONS: Similar maturation rates between ETS and STS fistula configuration, however, arterial steal syndrome was significantly associated with the STS technique. ETS will likely remain as the preferred AVF configuration as it is less technically demanding.

Preconditioning Shields Against Vascular Events in Surgery (SAVES), a multicentre feasibility trial of preconditioning against adverse events in major vascular surgery: study protocol for a randomised control trial.

BACKGROUND: Patients undergoing vascular surgery procedures constitute a 'high-risk' group. Fatal and disabling perioperative complications are common. Complications arise via multiple aetiological pathways. This mechanistic redundancy limits techniques to reduce complications that target individual mechanisms, for example, anti-platelet agents. Remote ischaemic preconditioning (RIPC) induces a protective phenotype in at-risk tissue, conferring protection against ischaemia-reperfusion injury regardless of the trigger. RIPC is induced by repeated periods of upper limb ischaemia-reperfusion produced using a blood pressure cuff. RIPC confers some protection against cardiac and renal injury during major vascular surgery in proof-of-concept trials. Similar trials suggest benefit during cardiac surgery. Several uncertainties remain in advance of a full-scale trial to evaluate clinical efficacy. We propose a feasibility trial to fully evaluate arm-induced RIPC's ability to confer protection in major vascular surgery, assess the incidence of a proposed composite primary efficacy endpoint and evaluate the intervention's acceptability to patients and staff. METHODS/DESIGN: Four hundred major vascular surgery patients in five Irish vascular centres will be randomised (stratified for centre and procedure) to undergo RIPC or not immediately before surgery. RIPC will be induced using a blood pressure cuff with four cycles of 5 minutes of ischaemia followed by 5 minutes of reperfusion immediately before the start of operations. There is no sham intervention. Participants will undergo serum troponin measurements pre-operatively and 1, 2, and 3 days post-operatively. Participants will undergo 12-lead electrocardiograms pre-operatively and on the second post-operative day. Predefined complications within one year of surgery will be recorded. Patient and staff experiences will be explored using qualitative techniques. The primary outcome measure is the proportion of patients who develop elevated serum troponin levels in the first 3 days post-operatively. Secondary outcome measures include length of hospital and critical care stay, unplanned critical care admissions, death, myocardial infarction, stroke, mesenteric ischaemia and need for renal replacement therapy (within 30 days of surgery). DISCUSSION: RIPC is novel intervention with the potential to significantly improve perioperative outcomes. This trial will provide the first evaluation of RIPC's ability to reduce adverse clinical events following major vascular surgery. TRIAL REGISTRATION: www.clinicaltrials.gov NCT02097186 Date Registered: 24 March 2014.

Zinc sulphate attenuates chloride secretion in human colonic mucosae in vitro.

Zinc's usefulness in the treatment of diarrhoea is well established as an addition to oral rehydration. Mechanisms of action of zinc have been explored in intestinal epithelia from rodents and in cell lines. The aim was to examine how zinc alters ion transport and signal transduction in human colon in vitro. Voltage clamped colonic sheets obtained at the time of surgical resection were used to quantify ion transport responses to established secretagogues. Nystatin permeabilisation was used to study basolaterally-sited ion channels. Direct actions of zinc were determined using preparations of colonic crypts isolated from human mucosal sheets. Electrophysiological measurements revealed zinc to be an inhibitor of electrogenic ion transport stimulated by forskolin, PGE(2), histamine and carbachol in isolated human colonic epithelium. Basolateral addition of zinc sulphate had no direct effect on the epithelium. To further outline the mechanism of action, levels of secondary intracellular messengers (3', 5'-cyclic adenosine monophosphate; cAMP) were determined in isolated colonic crypts, and were found to be reduced by zinc sulphate. Finally, indirect evidence from nystatin-permeabilised mucosae further suggested that zinc inhibits basolateral K(+) channels, which are critical for transepithelial Cl(-) secretion linked to water flux. Anti-secretory, and therefore anti-diarrhoeal, actions of exogenous zinc are due, at least in part, to direct basolateral epithelial K(+) channel inhibition.

The flavonone naringenin inhibits chloride secretion in isolated colonic epithelia.

Studies investigating the activating and inhibitory actions of bioflavonoids on colonic function have yielded conflicting results. At low concentrations, flavonoids may stimulate chloride secretion while at higher concentrations they may have antisecretory actions in the colon. Naringenin (4',5,7-trihydroxyflavanone), found predominantly in citrus fruits, confers a protective effect against colorectal cancer and is purported to modulate secretory function in colonic cell lines. The aim of this study was to investigate the effects of naringenin on ion transport in rat and human colonic mucosae. Naringenin inhibited basal and stimulated chloride secretion in rat and human colonic mucosae mounted in Ussing chambers (IC(50) 330 µMol/L and 360 µMol/L respectively) and did not alter intracellular cAMP generation. Naringenin inhibited chloride secretion in MQAE (N-(ethoxycarbonylmethyl)-6-methoxyquinolinium bromide) loaded crypts stimulated with forskolin. In BCECF (2',7'-bis-(2-carboxyethyl)-5-(and 6)-carboxyfluorescein acetoxymethyl ester) loaded crypts, naringenin caused an intracellular acidification (ΔpH/min=0.05 ± 0.004) which was sensitive to the Na-K-Cl co-transporter (NKCC) inhibitor bumetanide. In addition, the antisecretory effect of naringenin was not inhibited by blockade of barium sensitive basolateral K(+) transporters or by inhibition of Na+/H(+) exchange by amiloride. We propose that the antisecretory action of naringenin is due to inhibition of basolateral NKCC1 in rat and human colon.

Emerging role of hydrogen sulfide in colonic physiology and pathophysiology.

Hydrogen sulfide (H2S) is a toxic gas that is now recognized as an important mediator of many physiological processes. In the colon, H2S is produced both endogenously and by naturally occurring sulfate-reducing bacteria (SRB). The full arrays of its effects in the gastrointestinal tract are still being elucidated, but they range from motility to carcinogenesis. We examined the evidence relating to H2S as a modulator of colonic function and disease. H2S is implicated in modulation of colonic compliance through its action on smooth muscle. There is also evidence linking H2S to colonic nociception, inflammatory bowel disease (IBD), and colorectal cancer. The exact mechanisms and pathways by which H2S exerts its multitude of effects are not yet fully understood, but its involvement in physiological and pathophysiological conditions of the colon is becoming evident. Elucidating the intricate effects of H2S in the colon and understanding the exact nature of its interactions with the colon makes pharmacological modulation of H2S production and metabolism potential targets for treatment of a multitude of colonic conditions in the future.

Small bowel obstruction secondary to migration of a fragment of lithobezoar: a case report.

INTRODUCTION: Small bowel obstruction is a common world-wide condition that has a range of etiological factors. The management is largely dependent on the cause of the obstruction. Small bowel obstruction caused by foreign body ingestion is rare; many items have been reported as responsible, but there are no reports implicating polyurethane foam. CASE PRESENTATION: We report the case of a 44-year-old Irish male who presented following ingestion of polyurethane foam. He was asymptomatic on presentation but developed a small bowel obstruction shortly thereafter. CONCLUSION: Patients presenting following ingestion of polyurethane foam should be scheduled for elective laparotomy, gastrotomy, and retrieval of the cast on the next available theatre list - given that they are suitable for surgery.