Quick tips: initiating insulin in type 2 diabetes in primary care video 2 START AUDIO

Transcription

1 BMJ LEARNING VIDEO TRANSCRIPT Quick tips: initiating insulin in type 2 diabetes in primary care video 2 START AUDIO (Music) Martin Hadley-Brown: So usually when we re starting insulin, for someone with type 2 diabetes, we start with a single long acting injection of insulin, given at night. This gives some control of the basal level of glucose. We continue any tablets that the patient has been on usually alongside that single injection of insulin. That often will bring through the morning fasting blood sugar reasonably satisfactorily, and the more we can work on the day with tablets as and how we need to. We then titrate that dose of evening insulin so that the waking glucose the following morning is satisfactory, usually around the six to eight mark. In patients who have a particularly high glucose level, perhaps an HbA1c of over 10, there are some advantages to starting them off on a slightly more complex regiment of insulin, and often a mixed insulin or a long acting insulin plus a mealtime dose, with the main meal, might be instituted right from the start. So once we have in place that single injection of long acting insulin, which is how we usually start, we often do need to move forward as the disease progresses. Typically the next step is to add a second injection of that human NPH long

2 acting insulin, in the mornings. Some people use a single daily long acting injection of an analogue insulin, instead of the twice daily NPH, and that s often down to local guidelines. So again here we re trying to deal with the basal insulin requirement. Moving on from there if we have to add further insulin we can add some mealtime insulin, to deal with the mealtime peaks. This is where patient monitoring becomes quite important, because we can see what the post meal surges in blood sugar are, and then decide perhaps where to put a mealtime insulin in, whether it be perhaps with their lunch or with an evening meal. Some people prefer to move from long acting insulin preparations onto a mix. Personally I think you lose some of the flexibility doing that because you ve got your fixed 30:70 proportion, whereas if you use the insulin separately you can adjust the doses separately. So then I have, for example, the freedom to alter the long acting insulin so that I can get the waking glucose, in the morning, right, and the pre-bed sugar level right, and then I can deal with the mealtime surges separately with individual doses of prandial insulin. Now normally if we re using more than one type of insulin, so we ve introduced short acting insulins, we stop the other oral tablet medications for diabetes apart from Metformin. So you may remember that earlier I criticised us, as practitioners, for being too slow to start insulin. Our second problem, I m afraid, is that we tend to be too slow to increase the dose once we have started it. This is called dose titration. So typically we start someone with maybe a 10 unit dose of a long acting insulin at night, and we stop there and we wonder why control doesn t improve. So there s a need to titrate insulin dose up to that required by the individual patient. 2

3 We normally do that in steps of around 10% at a time once or twice a week. Ideally the education, information, and confidence that we ve given our patient, is going to enable them to do that without constantly having to refer back to us. So we ll have said to them, We are aiming perhaps for a waking glucose of 6 to 8 millimoles, increase your evening long acting insulin by 10% steps, once or twice a week, until you get to that stage. Obviously if you have any problems you refer back to us, but otherwise perhaps we see you when you ve attained that objective, and then move on with the next objective. Broadly with type 2 diabetes 10% increases in dose at a time work well. So, for example, we may have patients needing 60 to 80 units of insulin in a single dose late in the disease. It s not really any good making one or two unit increases in those doses. It will take you ages to get to target. So 10% increases is usually the guide I go by. Sometimes we will come to a situation where we need to reduce insulin dose. That may be, for example, because someone s managed to lose some weight or they re eating less and modified their diet, or they ve increased their exercise or whatever other reason. From the patient s point of view the key reason we would need to reduce insulin doses, is if they re getting hypoglycaemia. One of the parts of education is that they re very aware of what to look out for, either in terms of symptoms or the readings they re getting. We don t really want patients having readings below 4 to 5 millimoles at any time. When reducing doses I tend to reduce them in reasonably large steps, perhaps 20% at a time, because I m really trying to get rid of those hypoglycaemic events. They sap confidence and they re utterly horrible. So my rule to go by is up by 10%, down by 20%. 3

4 Some common pitfalls and problems with using insulin, in type 2 diabetes, would first be problems from the patient s point of view which I think comes down to hypoglycaemia, and we ve discussed a little bit how one deals with that. Also if people are not moving injection sites around, they can get quite lumpy injection sites. It s another part of education and of routine monitoring checks, to make sure that people are using the right site for their insulin. So hypoglycaemia from the patient s point of view, from patient and clinician s point of view failure to actually control and achieve the objectives that we re seeking. That s often due to not titrating the dose actively enough, not moving fast enough either upwards or downwards, to achieve objectives or to meet changes in patient behaviour. One or two other things that we need to make patients aware of, during education sessions, is the safe storage of insulin. Insulin will lose its effectiveness if it is frozen and it will lose its effectiveness if it gets too hot. So leave it on the windscreen in summer it s dead insulin. Freeze it when travelling it s dead insulin. So use of insulin that actually won t work is another occasional pitfall we come across. So when we re thinking of target points for blood glucose levels we re aiming for there s a very good mantra, which I think originated with Diabetes UK, four is the floor, five to drive. You don t want people going below four at all, when they re driving a bit of leeway. At the top end we re aiming to minimise the post meal peaks. We don t scare people too much if they go as high as 15, but I d like to see as few as possible of them going over the 10 mark. Prior to going to bed we advise people not to let their blood sugar go below about six to eight. Six to eight would be a target for going to bed, to minimise the risks of nighttime 4

5 hypoglycaemia. We re hoping that people will wake up with as near a normal blood glucose as possible, and that would be in the five to seven range. Now there will be some circumstances in which I will feel the need to refer a patient onto a specialist for advice. The first of those is where the patient or I are coming across problems, which we don t feel confident to solve. We re not specialists. We don t have the full experience that they have. I use them freely and find them extremely helpful and co-operative, when I need to ask for help. The second is when we re getting more serious complications of diabetes. So of course we ask our specialists for help with foot problems, foot ulcers, renal difficulties and of course when people need to go on for eye screening, but essentially if I m going beyond my comfort zone, or the patient s getting beyond their comfort zone, we get them to a specialist. So if I have to put forward three points that we mustn t forget in initiating insulin therapy, the first one is don t delay. We wait too long. I m not sure whether that s because of clinician reluctance or patient reluctance or a bit of both, but we must get that level of 9.8% as the HbA1c, when patients start insulin, down. It doesn t reflect well on us in the UK. My second point would be once that decision s been made prepare your patient and clinicians well. We need to know what we re doing, and we need to put in place structured education so the patient knows what they re doing. A third point would be don t just leave insulin as started. It then needs to be titrated, monitored, and adjusted on a constant basis, so that the patient and the clinician are confident that they re achieving the objectives they set originally. (Music) 5

6 END AUDIO 6