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A patient with high blood pressure
Published in Tim French, Terry Wardle, The Problem-Based Learning Workbook, 2022
High sympathetic tone disproportionately raises BP in hypertensive patients, or those who will develop hypertension compared with normotensive patients. A high resting pulse rate can be a manifestation of increased sympathetic activity, and is an accepted predictor of subsequent hypertension.
Pharmacology of Opioids
Published in Pamela E. Macintyre, Stephan A. Schug, Acute Pain Management, 2021
Pamela E. Macintyre, Stephan A. Schug
Opioids can reduce sympathetic tone, leading to hypotension and bradycardia. This is particularly likely in patients who have an increase in their sympathetic tone, such as those with pain or poor cardiac function, and patients who are hypovolemic. Opioids may also cause arterial and venous vasodilatation by a direct effect on vascular smooth muscle or through the release of histamine (notably morphine, diamorphine, pethidine [meperidine], and codeine). In clinical practice and particularly in the postoperative period, a significant decrease in blood pressure following administration of an opioid in a supine patient often indicates that the patient is hypovolemic. Postural (orthostatic) hypotension may occur when a supine patient given opioids sits or stands.
Trauma of the Brain and Spinal Cord
Published in Philip B. Gorelick, Fernando D. Testai, Graeme J. Hankey, Joanna M. Wardlaw, Hankey's Clinical Neurology, 2020
Fernando D. Goldenberg, Ali Mansour
In high cervical lesions, patients can develop respiratory compromise due to phrenic nerve injury and diaphragmatic paralysis. The sphincter tone may be lost and sacral functions compromised. Spinal shock results in hypotension and bradycardia due to loss of sympathetic tone. In comparison, hypovolemic shock presents with hypotension and tachycardia. Shock in patients with TSCI can be due to a mixed expression of loss of sympathetic tone, loss of muscle tone due to paralysis, and blood loss.
Pre-bout hypertension in the combat sports athlete: clearance recommendations
Published in The Physician and Sportsmedicine, 2023
Kevin deWeber, Ken S Ota, Cicely Dye
If an athlete’s pre-bout BP is in the severely elevated range, we also recommend performing an expanded history and physical examination to search for its underlying cause(s) (Table 3). In our collective experience, an expanded evaluation and repeated BP measurement will usually categorize hypertensive athletes into one of four categories: 1) spuriously elevated BP due to increased sympathetic tone from pre-bout anxiety; this type is most common and usually improves with rest and relaxation; 2) hypertension secondary to the use of supplements or drugs (Table 2); 3) persistently elevated BP that likely represents essential hypertension; or 4) hypertensive emergency (rare) in which there is evidence of cardiac, cerebral, or renal dysfunction, which would warrant referral to an emergency department for immediate treatment. Elucidating the underlying etiology can assist the ringside physician in clearance decisions to reduce the risk of cardiovascular or cerebrovascular morbidity. It can also assist the physician in athlete counseling and follow-up recommendations.
Prehospital Lactate is Associated with the Need for Blood in Trauma
Published in Prehospital Emergency Care, 2022
Eva V. Zadorozny, Tyler Weigel, Andre Stone, Danielle S. Gruen, Samuel M. Galvagno, Mark H. Yazer, Joshua B. Brown, Francis X. Guyette
When trauma patients are triaged en route to the hospital, they are often assessed based on their identifiable injuries, mechanisms of injury, and vital signs. However, these measures may not be sufficient to identify occult hemorrhagic shock (3). In patients with occult shock, vital signs appear normal early in the clinical course due to a compensatory increase in systemic vascular resistance and sympathetic tone. The masking of hemorrhagic shock by these compensatory mechanisms leads to tissue hypoperfusion without concomitant reductions in blood pressure (4, 5). Patients with occult shock may rapidly decompensate before they are identified with standard vital sign or physiologic measurements. Prehospital lactate measurement is a tool for evaluating hemorrhage independent of vital signs because of its ability to predict outcomes and the need for resuscitative interventions in trauma patients (5–8).
Gustatory rhinitis in multiple system atrophy
Published in Acta Oto-Laryngologica Case Reports, 2021
Kaoru Yamakawa, Kenji Kondo, Akihiko Unaki, Hideto Saigusa, Kyohei Horikiri, Tatsuya Yamasoba
PD, MSA, dementia with Lewy bodies, and pure autonomic failure are categorized as synucleinopathies, a group of neurodegenerative diseases caused by an abnormal accumulation of misfolded phosphorylated α-synuclein in the neurons, glia, or both [6,7]. Autonomic dysfunction is observed in synucleinopathies [8]. The sympathetic nervous system tends to be affected more than the parasympathetic system, which is indicated by the higher rate of orthostatic hypotension [8] and cardiac sympathetic denervation [9]. Therefore, the majority of autonomic nervous symptoms in these patients are based on the deficiency of sympathetic tone and relative predominance of parasympathetic tone. The observation of rhinorrhea is in line with this rationale, because it is caused by parasympathetic nerve hyperactivity in the nasal glands.