Oxygen carrying capacity in the clinical setting - a pilot
Research type
Research Study
Full title
Assessment of blood oxygen carrying capacity in the clinical setting - a pilot
IRAS ID
140666
Contact name
Toby Richards
Contact email
Sponsor organisation
University College London Hospital / University College London
Research summary
Why?
Haemoglobin, or Hb, is a protein found in the red blood cells that carries oxygen around the body and gives blood its red colour. Anaemia occurs when the number of red blood cells (and consequently their oxygen-carrying capacity) is reduced and is defined when haemoglobin concentration [Hb] is less than 13 g/dl for men and 12 g/dl for women.
A low haemoglobin concentration [Hb] may be due to a reduced amount of haemoglobin [total haemoglobin mass [tHb-mass)] or the fact that there is more ’water’ in the circulation, which dilutes its concentration. Thus, [Hb] may be stable and tHb-mass low in the context of acute bleeding, [Hb] normal or elevated but tHb-mass low in the context of dehydration, or [Hb] low but tHb-mass normal or high in the context of excess plasma volume (fluid). As a result, relying on [Hb] alone to define blood oxygen carrying capacity may lead to false interpretation. In contrast, the total haemoglobin mass (tHb-mass) represents the absolute mass of circulating haemoglobin in the body, which reflects the capacity of the blood to carry oxygen.
The quantity of haemoglobin molecules is important in two ways. On the one hand it directly increases oxygen transport and on the other hand it increases the volume of blood, which has an affect on the ability of the heart to pump blood around the body. tHb-mass, therefore, is important and may provide a better, more sensitive marker of oxygen carrying capacity and additional information on the clinical status of patients than measuring [Hb] alone.
What?
This research will utilise the carbon monoxide rebreathing procedure to measure total haemoglobin mass in patients from a number of different clinical populations by undertaking an observational pilot study. We will not be impacting on any medical treatment or therapy that patients will be undertaking.
Who?
We will offer the study to male and female adults (18 years or older) from the following patient groups: chronic heart failure, liver disease, surgical patients and patients with gastrointestinal disease.
Where?
This research will be carried out across three NHS Trusts; University College London Hospitals NHS Foundation Trust, the Royal Free London NHS Foundation Trust, Whittington Health.
How?
Patients will undergo the following as part of the study:
1. Baseline patient data collected: including, but not exclusively, diagnosis, medical history, and medications.
2. Venous blood sample - Blood serum and plasma (after being centrifuged) will be analysed for (but not exclusively), markers of iron status, hepcidin, other serum proteins (proteomics). In addition, genomic DNA will be extracted from blood samples
3. Urine sample - Proteomic and metabolomic analyses will be carried out on collected urine samples.
4. Carbon-monoxide rebreathing method to determine oxygen carrying capacity: including, weight, resting haematocrit & [Hb], and carboxyhaemoglobin concentration via capillary blood sample.Where possible, all data will be collected at 1 appointment to reduce any burden on the patient.
REC name
London - Camden & Kings Cross Research Ethics Committee
REC reference
13/LO/1902
Date of REC Opinion
13 Mar 2014
REC opinion
Further Information Favourable Opinion