Carotid blood velocity during cough studies in man.

Abstract

SUMMARY Utilizing a Doppler ultrasonic flownteter catheter, right carotid artery blood velocity was measured during 91 coughing episodes in 16 patients. Such coughing reduced carotid blood velocity by 40 ± 22% (control = 34 ± 8 cm per second, cough = 20 ± 9 cm per second, p < 0.001). There was an insignificant low degree of correlation between the level of simultaneously recorded mean right pressure and the percent decline of peak carotid blood velocity, suggesting that impaired venous return was not the only factor responsible for the observed changes. It is concluded that (1) coughing diminishes phasic carotid blood velocity and (2) reduced cerebral perfusion may play a role in the pathogenesis of cough syncope.COUGH SYNCOPE is a well-recognized clinical entity which has intrigued clinicians for approximately 100 years. Previous studies have documented the influence of tussive episodes on intrathoracic, cardiovascular or cerebrospinal fluid pressures 1 " 4 and changes in fluoroscopic images of the right atrium, vena cava and pulmonary vein. 5 In addition, EEG monitoring has been performed during the act of coughing. 3 We report here the influence of cough on phasic carotid arterial blood velocity. MethodsSixteen patients comprised the study group; there were 12 men and four women whose ages ranged from 23 to 58 with a mean of 44 years. Eight subjects had normal cardiovascular function and seven had coronary artery disease. One patient had mitral stenosis. No subject had symptoms suggestive of cough syncope. All diagnoses were established on the basis of right and left heart catheterization, indicator dilution curves and selective coronary cineangiography. Normal subjects were studied because of the presence of chest pain or systolic murmurs originally thought to represent heart disease. Patients were studied in a supine position in the postabsorptive state.Phasic instantaneous right carotid artery blood velocity was measured with a Doppler ultrasonic flowmeter catheter as previously described.6 ' 7 Under local anesthesia (1% lidocaine), the crystal-tipped catheter was introduced into a brachial arterial incision and advanced to the origin of the right carotid artery. In addition, a standard fluid-filled catheter connected to a Statham P23Db strain gauge was advanced from a medial antecubital vein to the right heart for the purpose of obtaining right atrial pressures. All subjects were instructed to cough in varying degrees while phasic carotid artery blood velocity, mean right atrial pressure and lead II of the ECG were recorded. Catheter tip position and stability were monitored by means of constant fluoroscopic image intensification. In six subjects, phasic aortic blood velocity also was recorded during cough.The Doppler catheter utilized in this study measured the velocity of blood cells flowing past its tip and reflected volumetric flow only as a function of stable arterial lumen diameter. ResultsNinety-one coughing episodes in the study group reduced peak carotid artery blood velocity by an average of 40 ...

Chest wall dynamics during voluntary and induced cough in healthy volunteers

“…In addition to measuring volume changes during coughing we were also able to calculate blood shift out of the trunk. Coughing is known to be associated with reductions in carotid artery (Desser et al 1976) and cerebral blood flow (Mattle et al 1995; Chao et al 2007), hypotension and bradycardia (Benditt et al 2005; Chao et al 2007), and on occasion can result in syncope. Whilst this study cannot shed light on the underlying mechanisms in cough syncope, it does suggest that during a peal of voluntary coughing significant haemodynamic shifts occur.…”

Paroxysmal Sneezing at the Onset of Syncopes and Transient Ischemic Attack Revealing a Papillary Cardiac Fibroelastoma

“…Furthermore, the rise in intrathoracic pressure is associated with a rise in intracranial pressure [1]. Moreover, it has been confirmed that coughing diminishes phasic carotid blood velocity and reduces cerebral perfusion [16]. In the past, “inability to sneeze” was observed after cerebral lesions [4, 5] and a variety of neurological disorders (other than syncope) were reported after sneezing; they included vertigo and deafness, subarachnoid haemorrhage and headache, drop attacks (in cases of Arnold-Chiari malformation), cerebrospinal fluid rhinorrhoea and pneumocephalus, or sudden quadriplegia after acute cervical disc herniation [1, 17].…”

Respiratory cerebrospinal fluid flow is driven by the thoracic and lumbar spinal pressures

“…It has previously been shown that short bursts of coughing can decrease the velocity of arterial flow (in the carotid and middle cerebral arteries) (Desser et al 1976;Chao et al 2007). Desser et al (1976) suggested that increased intracranial pressure caused by an influx of CSF may act to impede arterial flow into the cranium, as the velocity in the carotid artery was reduced by the cough but the velocity in the aorta was unaffected. This mechanism may explain the decreased arterial flow measured in this study ( Fig.…”