Bioimpedance Spectroscopy in Humans During Acute Fluid Volume Expansion With Different Crystalloid Solutions

The Hospital for Sick Children

Status: Completed

Conditions: HEALTHY

Treatments: Other: Treatment with D5; Other: Treatment with 0.9% normal saline; Other: Treatment with D5+ 0.45 saline

Study type: Interventional

Funder types: Other

Identifiers

NCT01930578

1000011897

Details and patient eligibility

About

The objective of the study is to identify a pattern of bioimpedance in humans during acute food changes. As a part of this study the investigators will be administering sodium bromide in oder to measure extracellular water via the bromide dilution technique.

Full description

The resistance of the human body to the flow of alternating current is thought to be related to the volume of fluid within the body. The acute change in fluid status of the human body alters the body resistance. This change can be measured accurately with bioelectrical impedance and previous experiments confirmed this observation. However, previous experiments using a piglet model and subsequently humans, suggested that the changes observed is a result of changes in salt instead of body water.

An experiment has shown that bioimpedance analysis (BIA) was able to detect changes in total body resistance when different electrolyte solutions were infused. The changes in resistance were related to changes in osmolarity and electro-ionic state, not to volume of water infused. Therefore, BIA measures principally the electro-ionic state. Thus a measurement of fluid volume can be indirectly obtained from BIA. However, in the non-steady state such as acute fluid volume expansion, the measurement of water volume cannot be performed accurately.

In this study, we will be administering sodium bromide in oder to measure extracellular water via the bromide solution technique. Despite the interesting observations, the human study described above was underpowered. Therefore, we aim to validate the observations that have been previously made through carrying out an appropriately powered study with an adequate sample size to validate the observations noted.

Enrollment: 15 patients

Sex: All

Ages: 18+ years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• Age > 18 years
• Otherwise healthy with no medical history of: cardiac disease, renal disease, chronic liver disease, diabetes, or lymphedema

Exclusion criteria

• Allergy to bromide
• Breast feeding mothers
• Pregnancy
• Heart failure
• Presence of a pace maker
• Renal failure
• Any contraindication to fluid bolus
• Recent or continued exposure to bromide containing drugs

Trial design

Primary purpose: Other

Allocation: Randomized

Interventional model: Crossover Assignment

Masking: None (Open label)

---

15 participants in 3 patient groups

Treatment with 0.9% normal saline

Experimental group

Description:

1 litre of normal saline infused over minutes and BIS performed at baseline, and 5 minute intervals during infusion, then 5 minute interval readings for 15 minutes after the stop of the infusion.

Treatment:

Other: Treatment with 0.9% normal saline

Other: Treatment with D5+ 0.45 saline

Other: Treatment with D5

Treatment with D5, 0.45 saline

Experimental group

Description:

1 litre of D5, 0.45 saline infused over minutes and BIS performed at baseline, and 5 minute intervals during infusion, then 5 minute interval readings for 15 minutes after the stop of the infusion.

Treatment:

Other: Treatment with 0.9% normal saline

Other: Treatment with D5+ 0.45 saline

Other: Treatment with D5

Treatment with D5

Experimental group

Description:

1 litre of D5 infused over minutes and BIS performed at baseline, and 5 minute intervals during infusion, then 5 minute interval readings for 15 minutes after the stop of the infusion.

Treatment:

Other: Treatment with 0.9% normal saline

Other: Treatment with D5+ 0.45 saline

Other: Treatment with D5