Pulse contour‐derived cardiac output in hemodialysis patients

Moysés

Hemodialysis International

et al. 2015

Parathyroidectomy (PTx) seems to improve cardiovascular outcomes and reduce blood pressure levels. However, the effect of PTx on hemodynamic changes during hemodialysis (HD) is still overlooked. This was a prospective cohort design. Patients with end-stage renal disease on maintenance HD were included. Diabetes and nonsinusal rhythm were exclusion criteria. History of PTx was recorded. Finometer monitor was used to access parameters immediately pre- and post-HD sessions. Cardiac index (CI) variation (ΔCI) and peripheral arterial resistance variation (ΔPAR) were the variables of interest. Biochemical and echocardiographic data were also obtained. PTx patients (n = 11) were matched to non-PTx patients (n = 20). ΔPAR was lower in PTx group in comparison with non-PTx group (P = 0.039), which was independent of parathyroid hormone (PTH) levels. Multiple regression analysis showed that PTx, ΔCI, and dialysate calcium remained independently associated with PAR variation and even adjusted for ultrafiltration rate (adjusted r(2) = 0.64). In conclusion, parathyroidectomized patients have impaired capacity of vasoconstriction in response to ultrafiltration, an effect independent of serum PTH levels. Further studies are needed to elucidate mechanisms explaining the interaction between PTx and systemic vascular tonus.

Section: Discussionmentioning

confidence: 73%

“…[16][17][18][19] In fact, one study found that the absolute cardiac output values reported by Finometer were unreliable. 20 As our focus was the variation of each hemodynamic variable from pre-to post-HD instead of the absolute values, we have judged our method trustworthy.…”

Section: Figurementioning

confidence: 99%

Parathyroidectomized patients have impaired capacity of peripheral vascular constriction during hemodialysis

Moysés

Hemodialysis International

et al. 2015

“…The only other study to address this question in hemodialysis patients was performed by Cordtz and Ladefoged . These investigators looked at 25 hemodialysis sessions in 25 patients, who underwent continuous monitoring with the Finometer, plus ultrasound dilution measurements at baseline and mid‐dialysis, i.e.…”

Section: Discussionmentioning

confidence: 99%

“…In accordance with previous literature, the difference between measurements was expressed both as an absolute value, and as a percentage of the mean of each measurement pair . One way analysis of variance ( ANOVA ) was used to look for significant differences in agreement between patients.…”

Section: Methodsmentioning

confidence: 99%

“…To date, only one preliminary study has taken advantage of this in order to validate the Modelflow approach in hemodialysis patients, and reported both substantial absolute error, and a lack of correlation between Finometer and ultrasound‐dilution measurements over time . This casts doubt on the conclusions of a body of literature investigating hemodynamic changes over hemodialysis.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Validation of Modelflow Estimates of Cardiac Output in Hemodialysis Patients

et al. 2018

Volume-clamp technology (e.g. Finometer) has become a popular method of collecting continuous, non-invasive, hemodynamic information during hemodialysis. There is minimal data validating the technique in this patient group. A gold standard cardiac output measurement can be obtained using ultrasound dilution in patients with arterio-venous fistulae. Continuous cardiac output was measured in 124 hemodialysis sessions in 27 patients using a volume-clamp device (Finometer PRO). Ultrasound dilution measurement was first taken at baseline (Transonic HD03), then used to calibrate the Finometer. Ultrasound dilution measurement was repeated 2 h into hemodialysis to assess drift following calibration. Pearson's correlation and Bland-Altman statistics, modified for repeated measures, were used to assess agreement between methods. Linear mixed models were constructed to identify factors that could explain session-level and patient-level variation in agreement. For baseline cardiac output before calibration, agreement between volume-clamp and ultrasound dilution measurements was poor, at 25 ± 75% (correlation 0.26, P < 0.001). There was significant variation in agreement between patients, with age, peripheral vascular disease and hemodialysis vintage contributing to poorer agreement. For cardiac output 2 h after calibration, agreement was -5.2 ± 57.5% (correlation 0.6, P < 0.001). Dynamic changes in blood pressure and fluid balance during hemodialysis resulted in greater drift over time after calibration. There was a large error, both random and systematic, in volume-clamp estimates of absolute, pre-calibration cardiac output in this prevalent hemodialysis population. There was minimal bias and reasonable correlation for cardiac output 2 h post-calibration, but limits of agreement remained too wide to meet current clinical standards.

Recent advances in the monitoring and control of haemodynamic variables during haemodialysis: a review

et al. 2011

The human body possesses a unique set of organs that are responsible for providing homeostatic balance to the body's fluids. Of these, the kidneys regulate fluid and electrolyte balance in order to maintain the intracellular and extracellular fluid volumes and ion composition within tight limits. When kidneys fail to function normally, fluid is retained and several ions and solutes accumulate. The consequences may be life threatening. Many kidney failure patients rely on haemodialysis (HD) as a life sustaining therapy to remove the waste products and excess fluid from the circulating blood. HD is based on the principle of diffusion of solutes and ultrafiltration of fluid across a semi-permeable membrane. Fluid removal during HD results in relative hypovolaemia during which the stability of a patient relies on compensatory mechanisms to maintain blood pressure (BP). The major compensatory mechanisms include sympathetic nervous system activation of peripheral vasoconstriction together with modest heart rate acceleration to ensure the haemodynamic stability of the patient. Over the years, many monitoring tools have been developed in the hope of predicting intra-dialytic hypotensive episodes. Similarly many methods have been utilized to prevent dialysis-induced complications: ultrafiltration and dialysate sodium profiling, varying ultrafiltration based on frequent BP measurements, etc. This paper provides a comprehensive review of those monitoring and control tools. It starts with a brief introduction to human kidneys and dialysis for non-specialized readers. The paper then reviews the monitoring tools that have been applied to assess the physiological response of patients during HD. This is followed by control techniques used to prevent dialysis-induced complications.