Advice

Technology overview

Technology overview

This briefing describes the regulated use of the technology for the indication specified, in the setting described, and with any other specific equipment referred to. It is the responsibility of healthcare professionals to check the regulatory status of any intended use of the technology in other indications and settings.

About the technology

CE marking

The Space GlucoseControl system is a Class IIb medical device. The manufacturer, B. Braun, received the first CE mark in June 2004. The most recent renewal was in May 2013.

Description

The Space GlucoseControl system comprises:

  • a control unit with a touch-screen interface

  • a computer running the eMPC algorithm to calculate the amount of insulin required for the next therapy interval

  • the Space pump infusion system, which delivers the insulin dose, as well as providing enteral or parenteral nutrition.

The Space GlucoseControl device is a decision support system that calculates an optimum level of insulin dosing. It consists of 3 infusion pumps, 2 for enteral and parenteral nutrition, and 1 for insulin. The system automatically records information from the nutrition pumps including current status of infusion, bolus doses and carbohydrate intake. It combines this information with manually-entered blood‑glucose measurements, administered insulin dose and patient‑specific data, such as previous response to insulin. A proprietary computer algorithm in the system, called the enhanced model predictive control (eMPC) algorithm, then predicts the future blood‑glucose curve and calculates the best insulin dose rate to keep blood glucose within the range specified by the clinician responsible for the patient's care. The dose rate can be set to achieve 1 of 3 blood‑glucose ranges: 4.4‑6.1 mmol/l, 4.4‑8.3 mmol/l or 5.6‑8.9 mmol/l.

Based on the eMPC algorithm prediction, the Space GlucoseControl system calculates the time interval to the next blood‑glucose measurement and gives an audio‑visual alarm to alert nursing staff when it is due. The nurse then measures and enters the current blood glucose value, and the system suggests an appropriate insulin dose and time to next measurement. The advised insulin dose rate has to be confirmed, and is then set automatically at the pump. Changes in enteral and parenteral nutrition are communicated directly to the eMPC by the respective pumps, and automatically lead revised insulin rate and measurement interval if appropriate. The system uses a variable sampling time, which is event‑based rather than time‑based, in order to minimise the number of blood‑glucose samples and reduce staff workload while maintaining the desired blood‑glucose range. The system increases the time between sampling if measured blood glucose is in line with its prediction, and decreases the time if the prediction is less accurate (such as when the patient's health changes unexpectedly). The sampling interval can vary between 30 minutes and 4 hours. The operator of the Space GlucoseControl system can reduce the maximum sampling interval to 3 hours, 2 hours or 1 hour if needed.

Intended use

The Space GlucoseControl system is intended for the control of blood‑glucose levels of patients in intensive care. The eMPC algorithm proposes an insulin dose rate calculated to keep the level within the normal glycaemic range, set by the clinician on a patient‑by‑patient basis.

Setting and intended user

The system is intended for use with critically ill patients in closely monitored environments, typically in hospital intensive care units. The manufacturer does not suggest that there are any patient groups in that setting for whom the system would not be suitable.

Current NHS options

Current protocols for blood‑glucose control in critically ill patients vary between hospitals. These involve a combination of continuous insulin infusion and frequent blood‑glucose test analyses. This should not be capillary blood which yields inaccurate results (Dellinger et al. 2013). Tests typically take place every 2 to 4 hours, leaving patients vulnerable if glucose levels change without warning. Numerous glucose management protocols have been developed to achieve glycaemic control, some of which use computer‑based algorithms. These protocols aim to maintain glucose levels in the healthy range, which is typically between 4.4 and 8.8 mmol/l, and base any change to the insulin infusion rate on either the absolute measured value or the change from the previous measurement.

Current practice includes devices which monitor glucose levels continuously and provide real‑time trending data, so that clinicians can intervene if the patient's glucose value moves outside the target range. As with Space GlucoseControl, these devices allow the adoption of event‑based protocols rather than time‑based measurement protocols. However, the information provided by these continuous glucose monitors is intended to supplement, not replace, readings obtained from approved blood‑glucose measuring devices, and should be confirmed before making any therapy adjustments.

NICE is not aware of other CE‑marked devices that have a similar function to the Space GlucoseControl.

Costs and use of the technology

For intensive care units already using B. Braun infusion pumps, the cost for adding the Space GlucoseControl computer module is £5500 per unit. Where B. Braun infusion pumps are not already in use, the cost of equipping a bed space with the minimum configuration for the Space GlucoseControl system is £12,300.

B. Braun guarantees the components of the Space GlucoseControl system for 24 months, and the system is expected to have a lifespan of 10 years if it is used under normal cleaning and care circumstances. The manufacturer provides both the initial training and further training and education updates free of charge throughout the lifespan of the device. The system is subject to a technical safety check every 2 years, carried out by B. Braun‑trained technicians. Individual service agreements take into account the specific requirements of each hospital. The eMPC computer module is an integral part of the system and cannot be used separately. No extra consumables are needed to use the system.

Likely place in therapy

The Space GlucoseControl system is intended to be used where glycaemic control is particularly important, such as intensive care units. It is intended to replace manual dose calculation and administration of insulin, and ensure that insulin therapy responds to changes in nutrition.

Specialist commentator comments

One specialist commentator reported that the Space GlucoseControl system reaches the target blood‑glucose range sooner and maintains it for longer than traditional protocols. They noted that for each patient there was an initial increase in workload while the sampling interval was high, followed by a reduction in workload once the target range was achieved. The commentator reported that some nurses were not confident that the 4‑hour interval between samples suggested by the Space GlucoseControl was sufficient, and therefore took samples more frequently.

The commentator noted that the Space GlucoseControl system was suitable for all patient groups. However, patients having bolus doses of carbohydrate or corticosteroids cause the machine to increase the sampling frequency, increasing the operator workload. The commentator also reflected that sampling equipment should be consistent for each patient, because fluctuations between arterial and capillary blood affected the time taken to reach the target range.

Another commentator considered the evidence that glycaemic control improves clinical outcomes to be mixed, because tight glycaemic control protocols are associated with an increase in hypoglycaemic episodes. Although some degree of glycaemic control is thought to be beneficial, the best level is unclear, and the benefits may vary between patient groups. Using the Space GlucoseControl system may increase blood‑glucose sampling above current levels, and it remains unclear whether there are significant patient benefits without additional resource use. Additionally, the specialist commentator noted that this system does not remove the risk of hypoglycaemia, and that evidence was needed to show that it could reduce this risk before its clinical or economic value could be assessed.

One commentator noted that although the manufacturer states that no consumables are needed for the Space GlucoseControl system, specific 'nutrition‑giving sets' need to be used with the machine. Extra costs may therefore be incurred if the system were not being used for all patients in an intensive care unit; 2 different nutrition sets would need to be stocked. Moreover, if the unit is not already using B. Braun glucose pumps, and another glucose‑infusion system is being used and interfaced with the Space GlucoseControl system, then B. Braun intravenous infusion sets would need to be purchased and stocked.

The commentator also reported that local protocols would be needed for using the Space GlucoseControl system, to specify when use of the system would start and for which patient groups it would be used, and also including a plan to manage hypoglycaemia. These protocols would form part of the training for use of the system, provide consistent management of glucose control, and clarify that the Space GlucoseControl system is not intended to replace clinical expertise.

Equality considerations

NICE is committed to promoting equality and eliminating unlawful discrimination. We aim to comply fully with all legal obligations to:

  • promote race and disability equality and equality of opportunity between men and women, and

  • eliminate unlawful discrimination on grounds of race, disability, age, sex, gender reassignment, pregnancy and maternity (including women post‑delivery), sexual orientation, and religion or belief, in the way we produce our guidance (these are protected characteristics under the Equality Act [2010]).

Men aged 70–74 and women aged 75–79 are treated in intensive care more often than people in any other age group. Age is a protected characteristic under the Equality Act (2010).