Carotid blood flow, cardiovascular and endocrine responses during head-up tilt in patients with acute cerebrovascular diseases

Abstract

The purpose of this study was to define common carotid blood flow (CBF), cardiovascular and endocrine responses during head-up tilt (HUT) in patients with acute cerebrovascular diseases (CVD). In 31 male patients with acute CVD (damage of the supratentorial area) and 21 age-matched control male subjects, we measured CBF, mean blood pressure (MBP), heart rate, stroke volume and cardiac output responses before (baseline), during and after HUT. We also measured plasma levels of antidiuretic hormone, adrenaline, noradrenaline, aldosterone and plasma renin activity. After obtaining baseline measurements during 3-minutes horizontal position, HUT was performed for 5 minutes, followed by continuation of recording for 3 more minutes in the horizontal position. During HUT, CBF decreased significantly and equally in both groups. MBP did not change during HUT in both groups. The endocrine responses were also not different between the two groups. The results suggest that damage to the supratentorial area in patients with acute CVD do not alter the CBF, cardiovascular and endocrine responses. In other words, HUT does not predispose patients with acute CVD to serious falls in MBP and CBF at upright posture.

Efficacy of heads‐up CPR compared to supine CPR positions: Systematic review and meta‐analysis

“…Additionally, It has also been shown that there was a significant decrease in the blood flow within carotid circulation in stroke patients when placed in the heads-up position. 20,21 This strengthens the argument that the utility of the heads-up CPR technique should be on a case-to-case basis and not "one size fits all." Thus, patients needing to be transferred, namely, cases that are taken from high-rise buildings, need to be considered separately because heads-up CPR may have possible adverse effects.…”

“…When CPR was used in combination with the transfer sheet (supine), it provided a higher mean depth of compression than the 45° and 90° stretchers. Furthermore, the percentage of depth‐enough reduction was higher in the transfer sheet patients than in the 45° stretcher group 20,21 …”

“…Furthermore, the percentage of depth‐enough reduction was higher in the transfer sheet patients than in the 45° stretcher group. 20 , 21 …”

“…Furthermore, the percentage of depth-enough reduction was higher in the transfer sheet patients than in the 45°stretcher group. 20,21 Of note, this discordance might be partially attributed to different techniques applied during CPR. Park et al 19 utilized LUCAS 2 chest compression system with an impedance threshold device (ITD) of 10 cmH 2 O.…”

Cerebral blood flow remains reduced after tilt testing in myalgic encephalomyelitis/chronic fatigue syndrome patients

“…Although the mechanism of the abnormal cerebral blood flow reduction in ME/CFS patients is not fully understood, one of the hypothesized mechanisms is that the abnormal cerebral blood flow reduction is related to an abnormal cardiac output reduction due to increased venous pooling and lack of venous return during the tilt test ( Timmers et al, 2002 , van Campen and Visser, 2018a ). It has previously been shown in healthy controls that cardiac output returns to normal pre-tilt test values within 1 min of the supine recovery phase ( Barde and Deepak, 2012 , Miyake et al, 2014 , Toska and Walløe, 2002 ). In ME/CFS patients the cardiac output in the post-test supine recovery phase has not been studied previously.…”