Measurement of Tissue Oxygenation Using Near-Infrared Spectroscopy in Patients Undergoing Hemodialysis

Summary

We present a protocol to measure regional oxygen saturation (rSO₂) in hemodialysis (HD) patients by using a near-infrared spectroscopy monitor. The rSO₂ value is an index of tissue oxygenation. This noninvasive and real-time monitoring could be useful for confirming changes in organ oxygenation during HD.

Abstract

Near-infrared spectroscopy (NIRS) has recently been applied as a tool to measure regional oxygen saturation (rSO₂), a marker of tissue oxygenation, in clinical settings including cardiovascular and brain surgery, neonatal monitoring and prehospital medicine. The NIRS monitoring devices are real-time and noninvasive, and have mainly been used for evaluating cerebral oxygenation in critically ill patients during an operation or intensive care. Thus far, the use of NIRS monitoring in patients with chronic kidney disease (CKD) including hemodialysis (HD) has been limited; therefore, we investigated rSO₂ values in some organs during HD. We monitored rSO₂ values using a NIRS device transmitting near-infrared light at 2 wavelengths of attachment. The HD patients were placed in a supine position, with rSO₂ measurement sensors attached to the foreheads, the right hypochondrium and the lower legs to evaluate rSO₂ in the brain, liver and lower leg muscles, respectively. NIRS monitoring could be a new approach to clarify changes in organ oxygenation during HD or factors affecting tissue oxygenation in CKD patients. This article describes a protocol to measure tissue oxygenation represented by rSO₂ as applied in HD patients.

Introduction

Near-infrared spectroscopy (NIRS) has been used to evaluate regional oxygen saturation (rSO₂), a marker of tissue oxygenation, especially cerebral oxygenation in various clinical settings^1,2,3 and has recently been applied to patients undergoing hemodialysis (HD)^{4,5,6,7,8,9,10,11}. Cerebral rSO₂

Protocol

All participants provided written informed consent. The study was approved by the Institutional Review Board of the Saitama Medical Center, Jichi Medical University, Japan (RIN 15–104).

1. Device for the monitoring of rSO₂

1. Prepare a NIRS device for measuring tissue oxygenation. This device has four channels and can perform measurement in up to four organs at the same time.
2. Prepare a measurement sensor for NIRS monitoring, to evaluate rSO₂ values in each organ via transmitting near-infrared light at two wavelengths of attachment.

2. Attaching the measurement s....

Results

Cerebral rSO₂ values before HD were lower than those in healthy subjects and cerebral rSO₂ in HD patients with diabetes mellitus (DM) were lower than those in HD patients without DM (Figure 1)¹⁶. Furthermore, although tissue oxygenation continues without a decrease of BP during HD, we incidentally observed changes in cerebral and hepatic rSO₂ due to intradialytic hypotension (Figure 2). Due to the continuo.......

Discussion

NIRS monitoring has been mainly used to evaluate cerebral rSO₂, especially in cardiovascular or cerebrovascular surgeries, which require extracorporeal circulation. During extracorporeal circulation including HD therapy, some organs could show relative ischemia^7,17,18; however, it remains unclear whether tissue oxygenation becomes low or not. Muscle cramps or abdominal pain during HD could be one of the prodromal symp.......

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
DBB-100NX	Nikkiso	DBB-100NX	Dialysis machine
INVOS 5100c	Covidien Japan	INVOSTM 5100c	tissue oxygenation device
SOMASENSER	Covidien Japan	CV-SAFB-SM/INTL	NIRS sensor