Some of frequent questions are below, but if you have any other questions about the eGFR-C study please contact the study team .

If a potential participant has a history of alcohol or drug abuse but it has stopped, are they excluded from the study?

No, if the alcohol or drug abuse is not a current problem then the patient can be included in the study.

When recording the time that the iohexol infusion is administered, what time should be used – the start or the finish?

The mid-point of the infusion should be recorded, although we will shortly add fields for recording both start and finish times on the CRF to automatically calculate the mid-point.

What should I do if our study blood pressure monitor has a problem?

The monitors are guaranteed until 17th February 2017. Before then it can be replaced – this should be arranged through Gillian Eaglestone, eGFR-C Lead Research Nurse ( geaglestone@nhs.net ).

Any operational queries can be individually telephoned or emailed to the dealer White Medical:
t: 01788 553904

What is the latest time the iohexol assessments can start?

As long as the participant adheres to the guidelines on permitted food, then the iohexol assessment can be started at any time before 12pm - as long as the participant is prepared to stay until as late as 4pm.

What time should be recorded as the start of the iohexol assessment?

The mid-point of the iohexol infusion will be used as the start of the assessment. The CRFs will ask you to record the start and finish times of the iohexol infusion and the database will calcuate the exact mid-point. When recording the subsequent blood sample times, please use the start time of the infusion to calculate the time (i.e. use 5 minutes from the start to work out the timing for the 5 minute sample).

The most important point is to accurately record the actual time, not to take the sample exactly 5 minutes later.

What should I do if a participant only has one arm available for sampling?

In some cases, such as if a female participant has severe lymphoedema after a mastectomy, a participant may only have one arm available for the iohexol administration and subsequent blood samples.

It is important not to sample from any high risk site. In this particular instance the approach is to use a single site for iohexol administration and blood sampling. The key is to ensure, as in the standard procedure, that that the iohexol is completely flushed in; nothing remaining in the line or any multi-way tap. Then as a second precaution, withdraw and discard the first 5ml of blood at the initial 5 minute sample.

Why are two needle sizes specified in the study guide?

The iohexol is quite thick and sticky and so it is better administered through the larger 21G needle. The finer, smaller 23G needles are kinder for repeated venepuncture in the event that you are unable to cannulate.

There is nothing in the in-pack safety leaflet about a recommended needle size. However, the 21G needle is what is generally easier for iohexol and has been specified in the study guide so that all sites follow the same procedure to limit possible variations.

Are meat and fish permitted before non-iohexol visits?

No; the permitted foods list should be followed from 10pm the night before in the same way as for iohexol assessments. Participants should be reminded of this if you speak to them before visits.