Toxic Megacolon in Crohn’s Colitis
Savio George Barreto, Shailesh V. Shrikhande in Dilemmas in Abdominal Surgery, 2020
Toxic megacolon is a condition traditionally characterized by gross colonic distension in the setting of severe colitis culminating in septic shock. In the acute scenario, biopsies from flexible sigmoidoscopy often cannot distinguish between ulcerative colitis or Crohn's disease. Surgery remains the mainstay of managing toxic megacolon due to inflammatory bowel disease and is often a life-saving procedure. The initial management of a patient with suspected toxic megacolon begins with securing the airway, providing supplemental oxygen, assessing the hemodynamic stability and cognitive state. An erect chest X-ray, with the inclusion of both domes of the diaphragm, is warranted to confirm the same before proceeding to emergency surgery. The findings of erythema, granularity, loss of submucosal vessels with deep ulceration, and spontaneous bleeding with contact or air insufflation often portends the risk for surgery. Tertiary centers often have a subspecialist colorectal surgical unit that must be involved early, should the need for surgery arise from failed medical management.
The patient with acute cardiovascular problems
Peate Ian, Dutton Helen in Acute Nursing Care, 2020
This chapter gives a clear understanding of the normal anatomy and applied physiology of the cardiac and circulatory systems and explains how altered physiology can lead to acute deterioration. An improved understanding of these principles will enhance nursing assessment and recognition of acute problems and enable an appropriate response to medical emergencies caused by cardiac and circulatory disorders. The structure and function of blood, mechanisms of clotting and the ABO and rhesus systems are outlined. The arterial and venous system, and the peripheral circulation and an understanding of common problems of the circulatory system are provided. How the nurse assesses the cardiovascular system and the identification of common problems and medical emergencies related to the cardiovascular system is provided along with information regarding how these are identified and managed. The role of haemodynamic monitoring in the assessment and management of therapies that optimise cardiac output and the functioning of the cardiovascular system is detailed.
Production of Aortic Valve Sound
Mano Thubrikar in The Aortic Valve, 2018
The role of the aortic valve in the production of the second heart sound has puzzled many researchers over the years. This chapter examines the timing of the second heart sound as it relates to other hemodynamic events and to the aortic valve motion. It considers the experiments used to study the origin of the second heart sound, and the theory of the aortic valve vibration that produces the sound. The chapter describes the production of the aortic component of the second heart sound. It is well recognized that the second heart sound has two main components: the aortic component and the pulmonary component. It has been suggested that the second heart sound may originate from any of the following mechanisms: a sudden snapping together of the Corpora Aranti, and the vibration of the whole heart and great vessels in response to sudden changes in the direction of flow or pressure.
The utility of novel non-invasive technologies for remote hemodynamic monitoring in chronic heart failure
Published in Expert Review of Cardiovascular Therapy, 2014
Thato Mabote, Kenneth Wong, John GF Cleland
Monitoring a patient’s hemodynamic status may be a revolutionary way to aid a ‘health maintenance’ strategy in which the physician strives to therapeutically keep the patient in an ideal hemodynamic range. Currently, home telemonitoring employs a ‘crisis-prevention’ approach. This strategy is still based on easily acquired measures such as heart rate, weight and blood pressure – measurements that are useful to help implement guideline-directed therapy but provide little information about impending decompensation or the risk of hospitalisation. Current systems provide limited information to personalize and adapt medication therapy for heart failure. Several innovative technologies that can remotely monitor estimates of cardiovascular hemodynamics, such as cardiac index, systemic vascular resistance, augmentation index and added heart sounds may enable earlier detection of heart failure decompensation. This editorial presents an overview of the innovative technologies that are available for non-invasive hemodynamic monitoring and maybe adapted for home telemonitoring for chronic heart failure.
The role of exercise hemodynamics in assessing patients with chronic heart failure and left ventricular assist devices
Published in Expert Review of Medical Devices, 2019
Aaron Koshy, Thomas Green, Anet Toms, Sophie Cassidy, Stephan Schueler, Djordje Jakovljevic, Guy A MacGowan
Introduction: Chronic heart failure is characterized by reduced exercise capacity. Invasive exercise hemodynamics are not routinely performed unless patients undergo transplant or left ventricular assist devices (LVAD) assessment, though now with readily available noninvasive devices, exercise hemodynamics are easily obtained. Our contention is that this is a valuable opportunity to acquire a more accurate measure of cardiac status in heart failure. Exercise hemodynamic measures such as cardiac power output can be carried out cheaply and effectively. Recent studies have highlighted the added value of exercise hemodynamics in prognostication of heart failure, and their role in assessing myocardial recovery in LVADs. Areas covered: In this review, we explore the literature available on Medline until 2019 focusing on resting and exercise hemodynamics alongside the methods of assessment (invasive and noninvasive) in heart failure with reduced ejection fraction and patients with implanted LVADs. Expert opinion: Hemodynamics measured both at rest and exercise are expected to play a significant role in the work up of transplant and LVAD patients. Furthermore, there is the potential to utilize noninvasive assessment in a complimentary fashion to support patient selection and improve the monitoring of response to treatment across the full cohort of heart failure patients.
School burnout and cardiovascular functioning in young adult males: a hemodynamic perspective
Published in Stress, 2014
Ross W. May, Marcos A. Sanchez-Gonzalez, Preston C. Brown, Andrew P. Koutnik, Frank D. Fincham
This study investigated aortic and brachial hemodynamic functioning that may link school burnout to cardiovascular risk factors. Methodological improvements from previous research were implemented including (1) statistical control of depressive and anxiety symptoms (2) resting, stress-induced and cardiac recovery condition comparisons and (3) use of pulse wave analysis. Forty undergraduate young adult males completed self-report measures of school burnout, trait anxiety and depressive symptoms. Participants then completed a protocol consisting of a 10-min seated rest, 5-min baseline (BASE), 3-min cold pressor test (CPT) and a 3-min recovery period (REC). Indices of brachial and aortic hemodynamics were obtained by means of pulse wave analysis via applanation tonometry. Controlling for anxiety and depressive symptoms, planned contrasts identified no differences in cardiovascular parameters at BASE between participants in burnout and non-burnout groups. However, negative changes in hemodynamic indices occurred in burnout participants at CPT and REC as evidenced by increased aortic and brachial systolic and diastolic blood pressures, increased left ventricular work and increased myocardial oxygen consumption. Findings suggest that school burnout symptoms are associated with cardiac hyperactivity during conditions of cardiac stress and recovery and therefore may be associated with the early manifestations of cardiovascular disease. Future studies are suggested to reveal underlying autonomic mechanisms explaining hemodynamics functioning in individuals with school burnout symptomatology.
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