scholarly journals A Study of Noninvasive Cardiac Output and Other Cardiorespiratory Parameters in Various Neurosurgical Positions

2016 ◽  
Vol 1 (1) ◽  
pp. 19-24
Author(s):  
Hemangi S Karnik ◽  
Aparna A Nerurkar ◽  
Nishant Bawankule

ABSTRACT Background Neurosurgical patients are operated in supine, prone, lateral, and sitting positions, which cause physiological changes in cardiorespiratory parameters. Noninvasive cardiac output (NICO) monitor developed by Novametrix Medical System Inc is a noninvasive cardiac output monitor, which also measures and displays other parameters like stroke volume, cardiac index, pulmonary capillary blood flow, alveolar and dead space ventilation, peak flow rates, airway pressures, and respiratory volumes. We felt that a study using the NICO monitor in anesthetized patients undergoing neurosurgery in different positions would quantify the cardiopulmonary changes, identify risk factors, and improve intraoperative management. Materials and methods A total of 40 consecutive patients undergoing neurosurgical procedures—20 in prone, 16 in lateral and 4 in sitting position—were studied. The hemodynamic and cardiorespiratory parameters were noted in supine position about 15 minutes after induction of general anesthesia using standard protocol and 15 minutes after giving surgical position using NICO monitor. Conclusion We conclude that under anesthesia, the prone and sitting positions negatively affect derived cardiac parameters like cardiac output, cardiac index, and stroke volume, and lateral position tends to improve these parameters while the respiratory parameters are not significantly affected. How to cite this article Karnik HS, Nerurkar AA, Bawankule N. A Study of Noninvasive Cardiac Output and Other Cardiorespiratory Parameters in Various Neurosurgical Positions. Res Inno Anaesth 2016;1(1):19-24.

2021 ◽  
Vol 74 (8) ◽  
pp. 1809-1815
Author(s):  
Ulbolhan A. Fesenko ◽  
Ivan Myhal

The aim of the study was to analyze cardiac function during Nuss procedure under the combination of general anesthesia with different variants of the regional block. Materials and methods: The observative prospective study included 60 adolescents (boys/girls=47/13) undergone Nuss procedure for pectus excavatum correction under the combination of general anaesthesia and regional blocks. The patients were randomized into three groups (n=20 in each) according to the perioperative regional analgesia technique: standart epidural anaesthesia (SEA), high epidural anaesthesia (HEA) and bilateral paravertebral anaesthesia (PVA). The following parameters of cardiac function were analyzed: heart rate, estimated cardiac output (esCCO), cardiac index (esCCI), stroke volume (esSV) and stroke volume index (esSVI) using non-invasive monitoring. Results: Induction of anesthesia and regional blocks led to a significant decrease in esCCO (-9.4%) and esCCI (-9.8%), while esSV and esSVI remained almost unchanged in all groups (H=4.9; p=0.09). At this stage, the decrease in cardiac output was mainly due to decreased heart rate. At the stage of sternal elevation we found an increase in esSV, which was more pronounced in the groups of epidural blocks (+23.1% in HEA and +18.5% in SEA). After awakening from anesthesia and tracheal extubation esSV was by 11% higher than before surgery without ingergroup difference. Conclusions: The Nuss procedure for pectus excavatum correction lead to improved cardiac function. increase in stroke volume and its index were more informative than cardiac output and cardiac index which are dependent on heart rate that is under the influence of anaesthesia technique.


2021 ◽  
pp. 43-46
Author(s):  
Yu.S. Lobanov ◽  
◽  
S.L. Lobanov ◽  
K.G. Shapovalov ◽  
◽  
...  

Aim of the study. To study alterations in macrohaemodynamics in diff erent modes of retropneumoperitoneum during retroperitoneal surgery. Material and methods. A total of 58 patients aged 40-60, both male and female, with previous surgeries on renal cysts through retroperitoneal approach were studied aft er distribution between 2 groups. In the fi rst group, the pressure did not exceed 12 mm Hg. The RPP in the second group was observed to be 12-16 mm Hg. During the surgical intervention, analysis of the cardiovascular system values was carried out using the method of volume compression oscillometry. Results. Evaluation of macrohaemodynamics revealed significant deviation of the indices in patients with high RPP (group 2). Elevated true systolic pressure was revealed, as well as cardiac output decrease by 20 %, decrease of the cardiac index by 24 % and decrease of the stroke volume by 11 %. Th e patients treated with application of the highest gas pressure in the retroperitoneal space were revealed to have decrease in the linear velocity of blood fl ow by 17 % and elevation of total systemic vascular resistance (TSVR) by 12 %. Conclusion. Th erefore, the RPP value of 12-16 mm Hg exerts significant influence on the patient’s macrohaemodynamic status


1987 ◽  
Vol 253 (6) ◽  
pp. H1335-H1341 ◽  
Author(s):  
T. L. Smith ◽  
T. G. Coleman ◽  
K. A. Stanek ◽  
W. R. Murphy

A new technique is described that allows minute-to-minute recordings of cardiac output and arterial pressure in unanesthetized rats for periods of 24 h and longer. Rats were instrumented with electromagnetic flow probes and arterial catheters. An electrical and hydraulic swivel was interposed between the rat and recording apparatus to allow free range of movement. Data were collected and analyzed once each minute by computer. Average 24-h values (mean +/- SD) for the following hemodynamic variables were determined in eight rats [expressed where appropriate as a function of body weight (BW)]: cardiac output (98.1 +/- 14.7 ml/min), cardiac index (29.2 +/- 4.4 ml.min-1.100 g BW-1), mean arterial pressure (92.5 +/- 7.8 mmHg), heart rate (347 +/- 45 beats/min), peak aortic flow (403 +/- 32 ml/min), stroke volume (282 +/- 26 microliters), stroke volume index (84.4 +/- 8.1 microliters/100 g BW), and total peripheral resistance index (3.26 +/- 0.46 mmHg.ml-1.min.100 g BW). These results provide a data base of hemodynamic values for unanesthetized adult, Sprague-Dawley male rats, which has not been previously available. In addition, cardiac index, mean arterial pressure, and total peripheral resistance index demonstrated diurnal variation. Diurnal variation contributed substantially to the overall variance observed within these variables. Hourly variance was also substantial and indicates the use of continuous recordings for short-term experiments.


PEDIATRICS ◽  
1964 ◽  
Vol 33 (6) ◽  
pp. 912-918
Author(s):  
Ann Sproul ◽  
Ellen Simpson

1. Catheterization data on 21 children between the ages of 6 and 16 years with no demonstrable hemodynamic abnormality were analyzed in order to establish normal values for blood flow in children. 2. The findings are: (a) Body surface area is a reliable standard of size for predicting cardiac output, stroke volume, and oxygen pulse. (b) Stroke volume is less variable than cardiac output or oxygen pulse since it is less affected at rest by minor variance from the basal state. (c) Cardiac index of 4.1 1/min/ m2 is valid within the surface area range of 0.7 to 1.2 m2. (d) Stroke index of 42 ml/beat/ m2 is valid within a surface area range of 0.7 to 1.5 m2. 3. Oxygen pulse is proposed as a sensitive index of the variance from basal state and as a useful flow measure for outpatient cardiac function studies. 4. A nomogram is presented for predicting cardiac output, stroke volume, and oxygen pulse from surface area.


1983 ◽  
Vol 54 (5) ◽  
pp. 1427-1433
Author(s):  
W. T. Dawson ◽  
R. L. Johnson

Plethysmographic (box) methods using N2O uptake to measure pulmonary capillary blood flow, right ventricular stroke volume, and pulmonary arterial flow pulse conduction time have been complicated by the presence of so-called “cardiogenic oscillations” in the box flow records on air and N2O breathing. The exact cause of these oscillations is unknown but believed to be secondary to instantaneous changes in net blood flow into and out of the thorax during the cardiac cycle. We examined these oscillations and pulmonary capillary blood flow in normal human subjects in a flow plethysmograph using a pressure compensation circuit to extend the frequency response. The cardiogenic oscillations in flow recorded at the mouth (with glottis open) are much greater in amplitude and 90 degrees out of phase from those recorded from the plethysmograph. We derived a theoretical analysis of this and designed an analogue electrical circuit to enable us to eliminate these oscillations by electrical subtraction from the box flow record generated by N2O uptake in the pulmonary capillary bed. Measurements of pulmonary capillary blood flow and ventricular stroke volume using our method correlate with measurements made with acetylene-rebreathing blood flow measurements performed sequentially at the same sitting.


2018 ◽  
Vol 29 (2) ◽  
pp. 127-132
Author(s):  
L. J. Delaney ◽  
R. Bellomo ◽  
F. van Haren

To describe the baseline hemodynamic variables and response time of hemodynamic changes associated with the Valsalva maneuver using noninvasive continuous cardiac output monitoring (Nexfin). Hemodynamic monitoring provides an integral component of advanced clinical care and the ability to monitor response to treatment interventions. The emergence of noninvasive hemodynamic monitoring provides clinicians with an opportunity to monitor and assess patients rapidly with ease of implementation. However, the responsiveness of this method in tracking dynamic changes that occur has not been fully elucidated. A prospective observational study was conducted involving 44 healthy volunteers (age = 38 ±12 years). Participants performed a Valsalva maneuvers to illicit dynamic changes in blood pressure, cardiac output, cardiac index, systemic vascular resistance index (SVRI), and stroke volume. Changes in these hemodynamic parameters were monitored while performing repeated standardized Valsalva maneuvers. Baseline hemodynamic values were obtained in all 44 participants, and showed an interaction with age, accompanying a significant decline in cardiac index ( r = –.66, p < .05) and stroke volume ( r = –.68, p < .05), and an increase in SVRI ( r = .67, p < .05) with increasing age. The Valsalva maneuver, performed in 20 participants, resulted in a change of 10% from baseline blood pressure and cardiac index, which was detected within 4.53 s ( SD = 4.36) and 3.31 s ( SD = 2.21), respectively. Noninvasive continuous cardiac monitoring demonstrated the ability to rapidly detect logical and predictable hemodynamic changes. These observations suggest that such Nexfin technology may have useful clinical applications.


2003 ◽  
Vol 95 (1) ◽  
pp. 3-10 ◽  
Author(s):  
M. Rohdin ◽  
J. Petersson ◽  
P. Sundblad ◽  
M. Mure ◽  
R. W. Glenny ◽  
...  

Both in normal subjects exposed to hypergravity and in patients with acute respiratory distress syndrome, there are increased hydrostatic pressure gradients down the lung. Also, both conditions show an impaired arterial oxygenation, which is less severe in the prone than in the supine posture. The aim of this study was to use hypergravity to further investigate the mechanisms behind the differences in arterial oxygenation between the prone and the supine posture. Ten healthy subjects were studied in a human centrifuge while exposed to 1 and 5 times normal gravity (1 G, 5 G) in the anterioposterior (supine) and posterioanterior (prone) direction. They performed one rebreathing maneuver after ∼5 min at each G level and posture. Lung diffusing capacity decreased in hypergravity compared with 1 G (ANOVA, P = 0.002); it decreased by 46% in the supine posture compared with 25% in the prone ( P = 0.01 for supine vs. prone). At the same time, functional residual capacity decreased by 33 and 23%, respectively ( P < 0.001 for supine vs. prone), and cardiac output by 40 and 31% ( P = 0.007 for supine vs. prone), despite an increase in heart rate of 16 and 28% ( P < 0.001 for supine vs. prone), respectively. The finding of a more impaired diffusing capacity in the supine posture compared with the prone at 5 G supports our previous observations of more severe arterial hypoxemia in the supine posture during hypergravity. A reduced pulmonary-capillary blood flow and a reduced estimated alveolar volume can explain most of the reduction in diffusing capacity when supine.


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