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Fluid balance monitoring by cuff-occluded rate of rise of peripheral venous pressure in haemodialysis patients
Version of Record online: 4 MAY 2012
Anaesthesia © 2012 The Association of Anaesthetists of Great Britain and Ireland
Volume 67, Issue 8, pages 894–898, August 2012
How to Cite
Pikwer, A., Bergenzaun, L., Sterner, G., Krite Svanberg, E. and Åkeson, J. (2012), Fluid balance monitoring by cuff-occluded rate of rise of peripheral venous pressure in haemodialysis patients. Anaesthesia, 67: 894–898. doi: 10.1111/j.1365-2044.2012.07165.x
- Issue online: 9 JUL 2012
- Version of Record online: 4 MAY 2012
- Accepted: 23 March 2012
Cuff-occluded rate of rise of peripheral venous pressure has been proposed to reflect volume changes in experimental studies. The aim of this study was to evaluate changes in cuff-occluded rate of rise of peripheral venous pressure associated with fluid removal by haemodialysis in six adult patients with chronic renal failure on intermittent haemodialysis. Measurements were carried out before and after each haemodialysis session. The volume of fluid removed (indexed to body surface area) linearly correlated with changes in cuff-occluded rate of rise of peripheral venous pressure (r = 0.84; r2 = 0.70; p = 0.037). Cuff-occluded rate of rise of peripheral venous pressure may be feasible for future clinical monitoring of individual fluid balance.
Central venous catheters have been proposed for central venous pressure (CVP) measurements when assessing right ventricular end diastolic filling , and intrathoracic positioning of the catheter tip is likely to be important for accurate measurements [2, 3]. However, changes in CVP have been reported to correlate with changes in more peripheral venous pressure [4–6]. The CVP has been reported to correlate with fluid responsiveness in animal  and clinical  studies, whereas many studies in healthy volunteers , intensive care patients  or patients undergoing surgery  report no such correlation.
Cuff-occluded rate of rise of peripheral venous pressure (CORRP), reflecting changes in peripheral venous pressure during proximal venous occlusion, has been proposed to predict hyper- or hypovolaemia in dogs [11, 12]. A small clinical study has indicated that CORRP may also be used for haemodynamic monitoring in humans . If this is better than CVP as a guide to volume status, it may resolve some of the differences in results referred to above.
Haemodialysis presents a situation in which controlled fluid removal occurs, and presents an opportunity to study such measures of volume status [14, 15]. This study was designed to assess changes in CVP, peripheral venous pressure, CORRP and non-invasively obtained mean arterial pressure, with fluid removal by haemodialysis in patients with chronic renal failure. The null hypothesis was that no significant correlation could be confirmed with any of these variables.
The study was performed in accordance with the Helsinki Declaration after permission had been obtained from the human ethics committee of Lund University. Each participant gave written consent.
Adult patients on intermittent haemodialysis thrice a week with a central venous catheter were recruited. Patients with a patent arteriovenous fistula (due to its potential haemodynamic influence ), cardiac valvular disease, atrial fibrillation, or moderate-to-severe heart failure (New York Heart Association Functional Classification 3–4 and left ventricular ejection fraction < 35%) were not included (Fig. 1).
The CVP was measured via the distal lumen of the dialysis catheter. The peripheral venous pressure was measured via a peripheral 20-G (1.1 mm diameter) 32 mm length Teflon catheter (BD Venflon™ Pro; BD Medical, Franklin Lakes, NJ, USA) positioned in a dorsal vein of the left hand. The catheters were connected to a patient monitor (GE Datex-Ohmeda S/5 Compact; GE Healthcare, Wanwatosa, WI, USA) via disposable pressure transducers. The CORRP was calculated (in mmHg.min−1) by linear model curve estimation regression analysis of the peripheral venous pressure curve during proximal venous occlusion, induced by instantaneous inflation (to ∼40 mmHg) of a 10-cm circumferential cuff positioned just proximal to the left elbow.
All measurements were carried out in the supine position before and after haemodialysis, and the volumes of fluid removed were recorded before, during and after leg raise (i.e. bilateral 45° passive elevation of both lower extremities). Leg raising was used for reversible induction of intravascular fluid challenges to assess central and peripheral pressure responses to increased return of venous blood. The CVP and peripheral venous pressure were measured continuously over 2-min periods for each study condition, and corresponding mean values were calculated. Mean CORRP values were calculated from six peripheral venous pressure measurements made in the flat supine position, and from three peripheral venous pressure measurements made during leg raise, in each patient. Each session of venous occlusion was followed by a 2-min period of baseline measurements of CVP and peripheral venous pressure.
The mean arterial pressure was determined with an oscillotonometric measurement device at the highest amplitude of oscillation in the occluding cuff observed during non-invasive measurement sequences completed thrice in the flat supine position and once during each leg raise manoeuvre.
SPSS version 17.0 software package with exact module (SPSS Inc, Chicago, IL, USA) was used for statistical analyses. The Wilcoxon signed ranks test was used to compare measurements obtained in the flat supine position with those made during leg raise, and to compare measurements made in the supine position before and after haemodialysis. The intra-patient reliability coefficient was estimated for CORRP in the supine position by the strict parallel method.
Pearson or Spearman correlation coefficients (r or rs, respectively) were calculated to assess correlation of the volumes of fluid removed indexed to body surface area [17, 18] with the changes in CVP, peripheral venous pressure, CORRP or mean arterial pressure (changes based on measurements made in the supine position before and after dialysis). Linear regression analysis was made for each statistically significant value of Pearson’s correlation coefficient and the coefficient of determination (r2) was reported and p levels < 0.05 were considered as indicating statistical significance.
According to sample size calculation (α = 0.05, 1−β = 0.8 and correlation coefficient = 0.96), based on previous experimental findings regarding correlation between change in fluid balance and CORRP , the required number of participants was five.
Six patients (one female) with a median (IQR [range]) age of 50 (47–63 [46–64]) years and a body surface area of 2.10 (1.83–2.28 [1.66–2.42]) m2 were included (Table 1). Five patients had a tunnelled catheter inserted via the right internal jugular vein (3 Bio-Flex Tesio 10.5 Fr and 2 Split Stream 14 Fr; Medcomp, Harleysville, PA, USA). One patient had a tunnelled catheter inserted via the left internal jugular vein (Bio-Flex Tesio 10.5 Fr; Medcomp). The tips of all catheters were found to have been positioned within the right atrium according to intra-operative fluoroscopy and post-procedural control chest X-ray.
|Patient number||Sex||Age; years||Body surface area; m2||Morbidity||Antihypertensive medication|
|1||Male||51||2.03||Hypertension, diabetes mellitus type I||Felodipine|
|2||Male||63||1.88||Hypertension, diabetes mellitus type 2, pancreatic insufficiency||Amlodipine|
|3||Female||49||2.17||Polycystic kidney disease, tobacco smoker||None|
|4||Male||64||1.66||Hypertension, chronic renal failure, tobacco smoker||Felodipine, ramipril|
|5||Male||46||2.24||Hypertension, diabetes mellitus type 2, posthaemolytic uraemic syndrome||Doxazosin, nifedipine, enalapril|
|6||Male||47||2.42||Hypertension, immunoglobulin A-mediated nephropathy||Metoprolol, felodipine, enalapril|
During haemodialys a median (IQR [range]) of 2.30 (1.42–3.68 [0.89–3.99]) l fluid, corresponding to 1.21 (0.61–1.73 [0.44–2.12]) l.m−2 indexed to body surface area, was removed. Before haemodialysis, leg raise was associated with significantly increased CVP (p = 0.031), but not peripheral venous pressure (p = 0.063), CORRP (p > 0.300) or mean arterial pressure (p = 0.063). After dialysis, leg raise was associated with significantly increased CORRP (p = 0.031) but not CVP (p = 0.063), peripheral venous pressure (p = 0.188) or mean arterial pressure (p = 0.094) (Table 2).
|Determinations made in the supine position|
|Before haemodialysis||After haemodialysis|
|Legs flat||With legs raised||Legs flat||With legs raised|
|Central venous pressure; mmHg||6 (5–10 [5–14])||8 (6–12 [6–16])*||5 (4–6 [2–8])||8 (4–9 [3–10])|
|Peripheral venous pressure; mmHg||12 (10–23 [10–29])||13 (11–28 [11–32])||11 (8– 18 [7–26])||13 (8–18 [8–27])|
|Cuff-occluded rate of rise of peripheral venous pressure; mmHg.min−1||63 (52–146 [37–173])||71 (59–148 [44–156])||51 (26–122 [25–167])†||71 (28–147 [25–205])‡|
|Mean arterial pressure; mmHg||111 (97–124 [89–135])||114 (100–125 [92–134])||122 (111–127 [97–135])||122 (115–135 [99–142])|
In the supine position, significant changes in CORRP (p = 0.031), but not in CVP (p = 0.156), peripheral venous pressure (p > 0.300) or mean arterial pressure (p > 0.300), were found in measurements before and after haemodialysis. The intra-patient reliability coefficient for CORRP in the supine position was 0.96 and 0.94 for measurements made before and after haemodialysis, respectively.
The volume of fluid removed indexed to body surface area showed a significant negative linear correlation with the change in CORRP (r = −0.84; p = 0.037), but not with the change in CVP, peripheral venous pressure or mean arterial pressure (all r < 0.50; p > 0.300). There was also a significant non-linear correlation between change in CVP and peripheral venous pressure (rs = 0.89; p = 0.019).
Linear regression analysis revealed a significant correlation between the volume of fluid removed indexed to body surface area and change in CORRP (r = 0.84; r2 = 0.70; p = 0.037) (Fig. 2).
The main result of this study is that the change in CORRP significantly correlates with the volume of fluid removed by haemodialysis, suggesting a potential clinical use of CORRP for bedside assessment of fluid balance. The similar responses in CVP to leg-raise manoeuvres before and after haemodialysis, and the lack of responses to removal of fluid, found in this study in spontaneously breathing patients without inotropic or vasoactive support, are in accordance with results obtained elsewhere, mainly in intensive care settings [9, 10, 15]. Immediate responses in CVP to rapid increases in central venous return of blood from passive leg raising are well known [19, 20], whereas slower changes in the plasma volume are less reliably reflected. This might be due to compliance of the venous system, and to humoural and sympathetic vasoactive compensation, enabling better adaptation to gradual changes in systemic fluid balance [19, 21].
The correlation of changes in peripheral venous pressure and CVP, found in this and in previous studies [22, 23], might be explained by compensatory peripheral responses to changes in central venous pressure. However, we speculate that the small sample size in this study might explain the absence of significant changes in peripheral venous pressure associated with leg raise before and after haemodialysis.
Our findings suggest that fluid removal by haemodialysis induces corresponding changes in CORRP in patients with no considerable cardiac dysfunction.
The large observed inter-individual variation (considerable interquartile range) in absolute CORRP values in our study might be attributed to baseline differences in clinical fluid balance. Inter-individual variations in other factors, including subcutaneous adipose tissue, venoarterial reflex or antihypertensive treatment, might also have contributed to differences in CORRP values between different patients. The significant change in CORRP, induced by leg raise after dialysis, and its linear correlation with the volume of fluid removed indexed to body surface area, may reflect corresponding changes in peripheral arterial blood flow and peripheral venous capacitance and compliance [11, 12, 24]. Lower CORRP values, as found after haemodialysis in our study, might have resulted from increased systemic vascular resistance as well as from decreased cardiac output, and decreased peripheral venous filling. Our higher CORRP values, compared with those reported previously , may be due to the relative hypervolaemic state of our patients with chronic renal failure compared with healthy volunteers.
Volumes of fluid removed by haemodialysis correlate linearly with changes in the CORRP. However, studies investigating the association of CORRP with cardiac output, arteriolar resistance and venous compliance would be important. It would also be desirable to assess if fluid administration guided by CORRP improves clinical outcome in various states of hyper- or hypovolaemia.
The authors thank Frida Fondelius for excellent administrative coordination of the study patients and Paul Rosenlöf for outstanding technical assistance. No external funding and no competing interests are declared.