Non-invasive cardiac output determination: state of the art

Kööbi, Tiit

doi:10.1097/00001503-199902000-00003

Cited by 13 publications

(8 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The cardiac output values measured with CircMon R whole-body impedance cardiography are in good agreement with the values measured by the thermodilution method, both in supine position and during head-up tilt [15]. A detailed description of the method and electrode configuration has been previously reported [15][16][17]. PWV was not assessed during the head-up tilt due to less accurate timing of left ventricular ejection during reduced stroke volume.…”

Section: Whole-body Impedance Cardiographysupporting

confidence: 60%

Reduced systemic vascular resistance in healthy volunteers with presyncopal symptoms during a nitrate‐stimulated tilt‐table test

Tahvanainen¹,

Koskela²,

Leskinen³

et al. 2010

Brit J Clinical Pharma

Self Cite

View full text Add to dashboard Cite

• Nitrates may facilitate syncope through various pathways, but the precise mechanism of nitrate-induced syncope is still under debate. The purpose of the present study was to compare the underlying haemodynamic mechanisms in subjects without and with presyncopal symptoms during a nitroglycerin-stimulated tilt-table test. WHAT THIS STUDY ADDS• A major decrease in systemic vascular resistance was documented in subjects with presyncope during 0.25 mg nitroglycerin-stimulated tilt-table test, in the absence of changes in cardiac output. These findings indicated that even a small dose of nitroglycerin significantly decreased arterial resistance and cardiac afterload. AIMSThe mechanism of nitrate-induced syncope remains controversial. We examined the haemodynamic changes in healthy volunteers during nitroglycerin-stimulated tilt-table test. METHODSContinuous radial pulse wave analysis, whole-body impedance cardiography and plethysmographic finger blood pressure were recorded in a supine position and during head-up tilt in 21 subjects with presyncopal symptoms (6 male/15 female, age 43 Ϯ 3 years) after 0.25 mg sublingual nitroglycerin and 21 control subjects (6 male/15 female, age 43 Ϯ 2 years). The drug was administered in the supine position and a passive head-up tilt followed 5 min later. Additionally, nitroglycerin was only administered during head-up tilt in 19 subjects and the haemodynamics were recorded. RESULTSSupine and upright haemodynamics were similar before nitroglycerin administration in the two groups. During the nitroglycerin-stimulated tilt test, aortic and radial mean blood pressure decreased significantly more in the presyncope group when compared with the controls (P = 0.0006 and P = 0.0004, respectively). The decreases in systemic vascular resistance (P = 0.0008) and heart rate (P = 0.002), and increase in aortic reflection time (P = 0.0002) were greater in the presyncope group, while the change in cardiac index was not different between the groups (P = 0.14). If nitroglycerin was administered during the upright tilt and not in supine position, the haemodynamic changes were quite corresponding. CONCLUSIONSPresyncopal symptoms during nitrate-stimulated tilt test were explained by decreased systemic vascular resistance and increased aortic reflection time, while cardiac output remained unchanged. These findings indicated reduced arterial resistance in nitroglycerin-induced presyncope.

show abstract

Section: Whole-body Impedance Cardiographysupporting

confidence: 60%

Reduced systemic vascular resistance in healthy volunteers with presyncopal symptoms during a nitrate‐stimulated tilt‐table test

Tahvanainen¹,

Koskela²,

Leskinen³

et al. 2010

Brit J Clinical Pharma

Self Cite

View full text Add to dashboard Cite

show abstract

“…Impedance changes during systole and diastole were used to calculate stroke volume. A more detailed description of this method is available in other publications 18,19 …”

Section: Methodsmentioning

confidence: 99%

Maternal haemodynamics in pre‐eclampsia compared with normal pregnancy during caesarean delivery

Tihtonen¹,

Kööbi

Yli‐Hankala

et al. 2006

BJOG

View full text Add to dashboard Cite

Objective To determine how pre-eclampsia modifies maternal haemodynamics during caesarean delivery.Design Prospective study.Setting Tampere University Hospital, Finland.Population Ten pre-eclamptic parturients and ten healthy parturients with uncomplicated pregnancies scheduled for elective caesarean section under spinal anaesthesia.Methods Haemodynamic parameters were assessed by whole-body impedance cardiography noninvasively.Main outcome measures Stroke index (SI), heart rate (HR), cardiac index (CI), systemic vascular resistance index (SVRI) and mean arterial pressure (MAP) were recorded before operation, continuously during caesarean section, during the period of dissipation of anaesthesia and on the second to fifth postpartum day.Results Baseline haemodynamics in women with pre-eclampsia differed significantly from healthy women in higher SVRI and MAP and lower SI and CI. In women with pre-eclampsia, preload infusion increased both SI and HR, causing a significant rise in CI, while in healthy parturients, only HR rose. In both the groups, spinal blockade reduced SVRI but CI remained stable. At the moment of delivery, CI increased in both groups. In uncomplicated pregnancies, both SI and HR increased, but in women with pre-eclampsia, SI was not altered and the rise in CI was due to an increase in HR only. After the reversal of anaesthesia, haemodynamics in the control group returned to baseline values, whereas in women with pre-eclampsia, SI and CI fell to levels that were significantly lower than the levels observed before surgery.Conclusions In women with pre-eclampsia, inability to increase SI at the moment of delivery may suggest dysfunction of the left ventricle to adapt to volume load caused by delivery and prompts concern for the increased risk of pulmonary oedema.

show abstract

“…The measurement of beat-to-beat stroke volume in this device is based on whole-body impedance cardiography (ICG WB ), and a detailed description of the method has been published previously (24,25). The accuracy and precision of cardiac output measurements using this method have been estimated in comparisons with thermodilution and the Fick method.…”

Section: Methodsmentioning

confidence: 99%