Prehospital Care
Prehospital management of syncope covers a wide spectrum of acute care and includes rapid assessment of airway, breathing, circulation, and neurologic status.
Treatment may require the following:
-
Intravenous (IV) access
-
Oxygen administration
-
Advanced airway techniques
-
Glucose administration
-
Pharmacologic circulatory support
-
Pharmacologic or mechanical restraints
-
Defibrillation or temporary pacing
Advanced triage decisions, such as direct transport to multispecialty tertiary care centers, may be required in select cases.
Emergency Department Care
In patients brought to the emergency department (ED) with a presumptive diagnosis of syncope, appropriate initial interventions include the following:
-
IV access
-
Oxygen administration
-
Cardiac monitoring
Electrocardiography (ECG) and rapid blood glucose evaluation should be promptly performed. A study to determine the sensitivity and specificity of the San Francisco Syncope Rule (SFSR) ECG criteria for determining cardiac outcomes found that when used correctly, the criteria can help predict which syncope patients are at risk of cardiac outcomes. [37] The SFSR ECG criteria predicted 36 of 42 patients with cardiac outcomes, with a sensitivity of 86%, a specificity of 70%, and a negative predictive value of 99%.
Syncope may be the manifestation of an acute life-threatening process but is generally not an emergency. Clinically ruling out certain processes is important. The treatment choice for syncope depends on the cause or precipitant of the syncope. Patients in whom a cause cannot be ascertained in the ED, especially if they have experienced significant trauma, should receive supportive care and monitoring.
Situational syncope treatment focuses on educating patients about the condition. For example, in carotid sinus syncope, patients should be instructed to avoid wearing tight collars, to use a razor rather than electric shaver, and to maintain good hydration status; they should also be informed of the possibility of pacemaker placement in the future.
Orthostatic syncope treatment also focuses on educating the patient. Inform patients about avoiding postprandial dips in blood pressure (BP), teach them to elevate the head of their bed to prevent rapid BP fluctuations on arising from bed, and emphasize the importance of assuming an upright posture slowly.
Additional therapy may include thromboembolic disease (TED) stockings, mineralocorticoids (eg, fludrocortisone for volume expansion), and other drugs such as midodrine (an alpha1-agonist with vasopressor activity). Patients' medications must be reviewed carefully to eliminate drugs associated with hypotension. Intentional oral fluid consumption is useful in decreasing frequency and severity of symptoms in these patients. [38]
The Syncope Evaluation in the Emergency Department Study (SEEDS) data suggested that specialized syncope units with protocoled approaches to ruling out cardiac causes of syncope reduce hospital costs and length of stay without compromising quality of care. [39] Data from subsequent studies confirmed these findings. [1]
Cardiac arrhythmic syncope is treated with antiarrhythmic drugs or pacemaker placement. Consider cardiologist evaluation or inpatient management, in that this is more commonly associated with poor outcomes. [2] Trials assessing beta-blockade to prevent syncope have conflicting results, [40] but no clear effect has been demonstrated.
In the prospective, multicenter Syncope Unit Project 2 (SUP 2) study, Brignole et al investigated the long-term effects and determinants of success of cardiac pacing in patients with severe unpredictable recurrent reflex syncope. Patients underwent carotid sinus massage (CSM), followed by tilt testing (TT) if CSM was negative, followed by implantation of an implantable loop recorder (ILR) if TT was negative; patients with an asystolic response to one of these tests received a dual-chamber pacemaker. The benefit of cardiac pacing was maintained at 3 years and was greatest in patients with negative TT. [41]
Cardiac mechanical syncope may be treated with beta-blockade to decrease outflow obstruction and myocardial workload. Valvular disease may require surgical correction. This, too, is associated with increased future morbidity and mortality.
Patients with select etiologies of syncope may require transfer for specialty evaluation or procedures.
Consultations
The etiology of syncope dictates the need, if any, for specialty consultation. Select cases may require consultation with a neurosurgeon, a neurologist, a cardiologist, a vascular surgeon, a cardiothoracic surgeon, an endocrinologist, or a toxicologist.
