Applied cardiovascular physiology

Abstract: The cardiovascular responses to exercise, haemorrhage, a Valsalva manoeuvre, postural changes and exposure to microgravity are complex patterns made up of a number of common physiological ‘building blocks’. The main cardiovascular response to isotonic exercise is an increase in cardiac output to elevate oxygen delivery to exercising muscle. This is largely mediated via an increase in heart rate and facilitated by an increase in venous return. By contrast, in haemorrhage a reduced venous return leads to a reduction in cardiac output, a fall in arterial pulse pressure and unloading of the arterial baroreceptors. The baroreceptor reflex response is designed to maintain arterial blood pressure by increasing peripheral vascular resistance and limiting the fall in cardiac output via a positive inotropic effect and tachycardia. But, because venous return falls in haemorrhage, the tachycardia is relatively ineffective in sustaining cardiac output (in contrast to the situation in exercise). As the haemorrhage becomes severe, a second reflex, causing a profound vagally mediated bradycardia and hypotension, becomes apparent. This ‘depressor’ reflex is blocked by the response to musculoskeletal injury, hence the biphasic response to ‘simple’ haemorrhage is often not seen in trauma patients. Changing posture and performing the Valsalva manoeuvre also reduce venous return and lead to a reflex tachycardia, an increase in peripheral resistance, a...
Source: Anaesthesia and intensive care medicine - Category: Anesthesiology Authors: Tags: Physiology Source Type: research

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CONCLUSIONS: We found very low-certainty evidence from four trials that was insufficient to conclude if there is any benefit of acupuncture, acupressure or laser at P6 point in reducing gagging and allowing successful completion of dental procedures. We did not find any evidence on any other interventions for managing the gag reflex during dental treatment. More well-designed and well-reported trials evaluating different interventions are needed. PMID: 31721146 [PubMed - in process]
Source: Cochrane Database of Systematic Reviews - Category: General Medicine Authors: Tags: Cochrane Database Syst Rev Source Type: research
Publication date: Available online 9 November 2019Source: Neuroscience ResearchAuthor(s): Kounosuke Hirata, Yuto Nishiki, Ryosuke Goto, Mikito Inagaki, Katsuo Oshima, Yoshihito Shimazu, Mamoru TakedaAbstractSystemic administration of the dietary constituent, resveratrol, was previously shown to inhibit the nociceptive jaw-opening reflex (JOR) via the endogenous opioid system. The present study investigated whether resveratrol could similarly affect the JOR under in vivo conditions via 5 H T3 receptor-mediated GABAergic inhibition. We used electrical stimulation of the tongue in pentobarbital-anesthetized rats...
Source: Neuroscience Research - Category: Neuroscience Source Type: research
Authors: Chaudhary B, Tripathy PR, Gaikwad MR Abstract Vertebral artery is a branch of 1st part of subclavian artery. Vertebral artery arising from the aortic arch most commonly presents on the left side. The cervical part of sympathetic trunk is closely related to the vertebral artery in the cervical region. Though lots of variations regarding anomalous origin, course of vertebral artery is reported in the literature, here we present a rare anomaly in which vertebral artery after originating from aortic arch is passing through stellate ganglia and it enters into the transverse foramina of higher cervical vertebra ...
Source: Folia Morphologica - Category: Anatomy Tags: Folia Morphol (Warsz) Source Type: research
This study aimed to evaluate the suppressive effects of a small dose of butorphanol on sufentanil-induced cough during general anesthesia induction. Methods: 120 patients who were scheduled for elective maxillofacial surgery of American Society of Anesthesiologists I∼II, aged 18∼65 years were randomly divided into 3 groups (n = 40). Patients received butorphanol 0.1 mg (group I), 1 mg (group II) or an equal volume of 0.9% normal saline (group III) 5 seconds right before sufentanil bolus (0.5ug/kg). Sufentanil was diluted into 5ug/mL and administrated within 5 seconds. The incidence and reflex degree ...
Source: Journal of Craniofacial Surgery - Category: Surgery Tags: Clinical Studies Source Type: research
Conclusions Acute oculomotor palsy may be a risk factor for rupture of ipsilateral unruptured aneurysms, but more basic research and clinical trial evidence of intracranial aneurysms are needed to confirm this.
Source: Medicine - Category: Internal Medicine Tags: Research Article: Clinical Case Report Source Type: research
Abstract The common degu (Octodon degus) is an emerging model in biomedical science research due to its longevity and propensity to develop human-like conditions. However, there is a lack of standardized techniques for this non-traditional laboratory animal. In an effort to characterize the model, we developed a chromatic pupillometry setup and analysis protocol to characterize the pupillary light reflex (PLR) in our animals. The PLR is a biomarker to detect early signs for central nervous system deterioration. Chromatic pupillometry is a non-invasive and anesthesia-free method that can evaluate different aspects ...
Source: Experimental Eye Research - Category: Opthalmology Authors: Tags: Exp Eye Res Source Type: research
Conclusion: Leptin stimulates efferent sympathetic outflow to the stomach and spleen through the hypothalamic AMPK.
Source: In Vivo - Category: Research Authors: Tags: Experimental Studies Source Type: research
This study provides novel evidence of increased H ‐reflex excitability in a mouse model of diet‐induced obesity. Sex differences in the time course of the reduction in rate‐dependent depression of the H Reflex suggest males respond with an early increase in H‐reflex excitability, whereas females show a progressive increase in reflex excitab ility. AbstractObesity is associated with balance and motor control deficits. We have recently shown that Group Ia muscle spindle afferents, the sensory arm of the muscle stretch reflex, are less responsive in mice fed a high ‐fat diet. Here we test the hypothesis that reflex ...
Source: Physiological Reports - Category: Physiology Authors: Tags: Original Research Source Type: research
This article aims to evaluate the effectiveness, security, and performance difficulty of GIB in patients with pelvic and perineal oncological pain.MethodsA retrospective study between January 2016 and August 2017. Patients with poorly controlled pelvic oncological pain and patients experimenting opioid side effects in which GIB was performed ambulatory were included. Prognostic GIB was performed, under echographic and fluoroscopic control, with local anesthetic and corticoid. The neurolytic block was performed under fluoroscopic guidance. The technique was performed by the same anesthetist with pain management competence. ...
Source: Supportive Care in Cancer - Category: Cancer & Oncology Source Type: research
ObjectivesThe local anesthetic bupivacaine is a common analgesic adjuvant medication used in combination with opioids in intrathecal drug delivery systems (IDDSs). While the acute effects of spinal bupivacaine injection on blood pressure (BP) have been studied, there is a dearth of data regarding long ‐term effects of continuous intrathecal bupivacaine infusion.Materials and MethodsA retrospective review of all noncancer pain patients receiving bupivacaine through IDDSs from January 2013 to November 2017 was performed. Blood pressure values before implantation, and after implant at the 1 ‐week, 3‐month, 6‐month and...
Source: Neuromodulation: Technology at the Neural Interface - Category: Biotechnology Authors: Tags: Clinical Research Source Type: research
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