Related Experiment Video
Updated: Jun 14, 2026
06:11
Employing the Forced Oscillation Technique for the Assessment of Respiratory Mechanics in Adults
Published on: February 9, 2022
A simple approach for assessing equilibrated Kt/V beta 2-M on a routine basis
Francesco G Casino1, Luciano A Pedrini, Antonio Santoro
1Nephrology, Ospedale Madonna delle Grazie, Matera, Italy. asl4.dialisi@rete.basilicata.it
Summary
A new method accurately estimates beta-2-microglobulin removal during high-flux hemodialysis (HD), providing a simple tool to assess treatment adequacy and middle molecule clearance. This approach aids in understanding dialysis effectiveness.
Area of Science:
- Nephrology
- Renal Replacement Therapy
- Dialysis Technology Assessment
Background:
- High-flux hemodialysis (HD) and convective techniques are associated with reduced morbidity and mortality compared to low-flux HD.
- Assessing middle molecule (MM) removal efficiency is crucial for optimizing dialysis treatment.
- Beta-2-microglobulin (beta2-M) is a key marker for MM removal, necessitating a practical method for its evaluation.
Purpose of the Study:
- To develop and validate a simplified method for routine assessment of single-pool Kt/V for beta-2-microglobulin (spKt/V(beta2-M)).
- To provide an easy-to-use tool for monitoring the efficiency of high-flux HD and convective therapies in MM removal.
- To compare the proposed method with existing techniques used in large observational studies.
Main Methods:
- Derived a novel equation for spKt/V(beta2-M) based on Leypoldt's formula, incorporating patient weight and beta-2-microglobulin concentration ratios.
- Assumed urea distribution volume (V(u)) as 49% of body weight (W) and beta-2-microglobulin volume (V(beta2-M)) as V(u)/3.
- Compared calculated spKt/V(beta2-M) values with the HEMO Study method (HM) in 129 patients across 407 dialysis sessions.
Main Results:
- The proposed equation (F) yielded mean spKt/V(beta2-M) values very close to the HM method (1.48 +/- 0.38 vs 1.47 +/- 0.37).
- Agreement between the methods was high, with differences less than +/-0.1 in 95% of cases.
- Predicted mean end-session beta-2-microglobulin rebound of 44% led to an approximate 27% reduction in actual Kt/V(beta2-M) (eKt/V(beta2-M) = 1.08 +/- 0.26).
Conclusions:
- The developed method offers a simple and effective tool for estimating spKt/V(beta2-M) and eKt/V(beta2-M) in routine clinical practice.
- This approach can monitor the efficiency of high-flux HD and convective techniques, evaluating adequacy of middle molecule removal.
- Further validation in a larger patient population is recommended to confirm its widespread applicability.
Related Concept Videos
01:20Assessment of Ventilation I: Respiratory Rate
Assessment of Ventilation
A Ventilation assessment is critical for monitoring a patient's health status. Respiration, one of the most accessible vital signs, provides insights into the function of numerous body systems and can indicate serious health issues, such as brainstem injuries from head trauma.
Critical Guidelines for Assessing Ventilation:
A Ventilation assessment is critical for monitoring a patient's health status. Respiration, one of the most accessible vital signs, provides insights into the function of numerous body systems and can indicate serious health issues, such as brainstem injuries from head trauma.
Critical Guidelines for Assessing Ventilation:
01:20Estimation of k and VD of Aminoglycosides
Aminoglycosides are a class of antibiotics used to treat various bacterial infections. Clinicians must determine the elimination rate constant (k) and volume of distribution (VD) to optimize therapeutic efficacy and minimize toxicity. The k value represents the rate at which the drug is removed from the body, and the VD reflects the degree to which the drug distributes into body tissues. Accurately estimating these parameters allows healthcare professionals to tailor drug dosing to individual...
01:29Assessment of Ventilation II: Respiratory Depth and Rhythm
Respiratory Depth
Respiratory depth measures the volume of air inhaled or exhaled during a breath. It can vary from shallow to deep and typically remains consistent when a person is at rest or asleep. Occasionally, individuals will automatically inhale deeply, known as sighing, which inflates the lungs with more air than normal breathing.
To assess respiratory depth, observe the degree of chest excursion or movement:
Respiratory depth measures the volume of air inhaled or exhaled during a breath. It can vary from shallow to deep and typically remains consistent when a person is at rest or asleep. Occasionally, individuals will automatically inhale deeply, known as sighing, which inflates the lungs with more air than normal breathing.
To assess respiratory depth, observe the degree of chest excursion or movement:
01:24One-Compartment Open Model: Wagner-Nelson and Loo Riegelman Method for ka Estimation
This lesson introduces two critical methods in pharmacokinetics, the Wagner-Nelson and Loo-Riegelman methods, used for estimating the absorption rate constant (ka) for drugs administered via non-intravenous routes. The Wagner-Nelson method relates ka to the plasma concentration derived from the slope of a semilog percent unabsorbed time plot. However, it is limited to drugs with one-compartment kinetics and can be impacted by factors like gastrointestinal motility or enzymatic degradation.
On...
On...
01:23Assessment of Respiration
The respiratory system's basic structures and primary functions lay the foundation for nurses' comprehensive respiratory assessments. This assessment includes subjective and objective data to gauge the patient's respiratory health.
Subjective Assessment: Nurses interview the patient to gather information directly during the subjective assessment. It includes questions about the individual's medical history, medications, and symptoms, focusing on past respiratory conditions like asthma or COPD,...
Subjective Assessment: Nurses interview the patient to gather information directly during the subjective assessment. It includes questions about the individual's medical history, medications, and symptoms, focusing on past respiratory conditions like asthma or COPD,...
02:05Calculating Equilibrium Concentrations
Being able to calculate equilibrium concentrations is essential to many areas of science and technology—for example, in the formulation and dosing of pharmaceutical products. After a drug is ingested or injected, it is typically involved in several chemical equilibria that affect its ultimate concentration in the body system of interest. Knowledge of the quantitative aspects of these equilibria is required to compute a dosage amount that will solicit the desired therapeutic effect.
A more...
A more...