CRITICAL ILLNESS AND INTENSIVE CARE: I

Design, organization andstaffing of the intensive careunitSean Bennett

AbstractThe location and size of the intensive care unit (ICU) should be carefully

planned to take into account the types of patients currently needing the

unit and which services are planned for the future. The Health Building

Note (HBN) 57 gives precise detail of the building requirements for

a new adult critical care facility. This has been recently amended to

account for the NHS commitment to patient privacy and dignity. Compre-

hensive Critical Care. A Review of Adult Critical Care Services, published in

2000, gives direction and advice on issues around organization and staff-

ing. Though not produced as a national service framework, it makes key

recommendations about the need for a ‘critical care delivery group’, inten-

sive care trained medical staff, level of patient dependency, audit collec-

tion and many other aspects of the ICU. It also gives a timeframe for

introducing these measures.

Levels of medical staffing and patterns of work are discussed. For many

ICUs a closed system with a ‘week-on’ consultant pattern produces good

results even if medical staff are working with a special interest in inten-

sive care rather than being specifically intensive care trained.

Keywords Critical care; consultant work pattern; mortality

Emergencycare

Radiology

Infection contol

Pathology

Pharmacy

Sterile supplies

CRITICALCAREAREA

In-patientacute

services

OPERATINGTHEATRE

Schematic layout for ICU from HBN 57

Introduction

The ICU should be large, airy, offer privacy, be located close to

admitting areas, have easy access to imaging, be quickly evac-

uated and allow patients to be observed all of the time. It should

have a leader who can understand all aspects of care e care

which should follow patterns dictated by evidence-based practice

and be administered in a full-proof way. Everyone working

should know all about the patients with robust plans for

admissions as required. Fully trained medical staff should be

available at all times.

This is never possible, due to conflicting issues and

constraints. The ICU should therefore be the best fit for the

population it serves.

Design

Before a brick is laid, it is important to consider the current and

future demands for critical care in your trust and region. This

might simply be an increasingly ageing population but can

Sean Bennett MB ChB FRCA FFICM is a Consultant in Intensive Care and

Anaesthesia and Honorary Senior Lecturer at the Hull York Medical

School Department of Anaesthesia, Castle Hill Hospital, Cottingham,

UK. Conflicts of interest: none declared.

SURGERY 30:5 214

include the movement of other services such as accident and

emergency, cancer, cardiac surgery etc. Not only might they be

moving in, they might be moving out. Generally the specific

monitoring requirements around the bed spaces can be consid-

ered as standard for level 2 and 3 patients, but the numbers must

be carefully thought through. Help is available with mathemat-

ical modelling.1

Next, where to locate the intensive care unit? Figure 1 shows

an idealized location plan which has been used in many hospi-

tals. Using this concept it is difficult to provide natural light and

suitable accommodation for relatives and staff.

The specific aspects of design are described in the 80 pages of

the government document HBN 572, ‘Facilities for Critical Care’.

This was published first in 2003, amended in 2005 and had

a minor alteration in 2010 to account for the ‘privacy and dignity’

NHS policy.

Its main points are to: increase bed areas, increase the

proportion of single rooms, reduce hospital-acquired infections,

acknowledge patients’ right to privacy and dignity, reduce noise

and maximize use of natural light.

It is a patient-centred design in which views from patients and

staff are considered. For example the commonest concerns about

current design were found to be: lack of space and privacy, too

few single rooms, and too much noise. Where design could help,

this was addressed. Therefore the bed-space area is now rec-

ommended to be 26 m2, even in twin bays (Figure 2). Single

rooms, also 26 m2, offer privacy and quiet but may necessitate

more nurses for a given number of patients. The large area

allows bed-side procedures to be carried out such as chest drains,

tracheostomies etc, without having to move the patient. It

recommends 50% of bed-spaces should be as single rooms with

Located within same buildingEasily accessibleAdjacent

Figure 1

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Figure 2 Twin bay. Figure 4 Glass screen.

CRITICAL ILLNESS AND INTENSIVE CARE: I

a projection of all rooms being single (Figure 3). With single

rooms comes an increased demand on room ventilation so that

the patient can be isolated by use of air flow, which ideally

should be bi-directional. Cubicles for isolation require a gowning

air-lock room which adds around 7 m2 to the cubicle. All spaces

must be wide enough (2.5 m) to allow a range of specialist ICU

beds though.

ICU is not exempt from delivering same-sex accommodation.

However, it is recognized that some patients need observation

and treatment which may result in exposure. It is expected that

no patient or relative should be able to see or overhear personal

aspects of another patient’s care. Curtains and screens can be

used but fixed glass screens with internal blinds are probably

better (Figure 4). Also available are glass screens with the

property of being turned ‘on’ (clear) or ‘off’ (opacified), so-called

‘smart or PolyvisionTM glass’.

The most recent version of HBN 57 is available free of charge

at ‘Space for Health’ via NHS e-mail.

Design is regulated but includes a lot of what one feels is right.

Scott gives a good account of building an ICU using HBN 57.3

A non-hostile environment is preferable although adding extra

Figure 3 Glass cubicle.

SURGERY 30:5 215

touches has no impact on outcomes.4 Wenham discusses how

a non-hostile environment can be created and its effect on

reducing delirium and the consequent length of stay.5

Organization

This can be divided into organizing the services coming into ICU,

and organizing services within a critical area. For example do

you mix general medicine with general surgery? Do you mix

general surgery with cancer surgery or other specialties like

gynaecology? Do you mix neurosurgery with any of the above?

The answer is more traditional than scientific.

The government recommendation in Comprehensive Critical

Care is ‘critical care without walls’ and that the hospital as

a whole should have a say in the organization of critical care,6

specifically by implementing critical care delivery groups and

regional networks. Typically areas like cardiac and neurosurgery

have been on their own while other specialties have wanted to

group together. Why is that? Early on it was shown that certain

specialties of very complex work achieved better results if they

did higher volumes.7 Cardiac surgery has a high turnover with

only one in 20 patients requiring care longer than a day or so, but

it is an important time for which critical care is needed. The high

turnover produced many patients, so cardiac surgeons were

reluctant to lose beds to other specialties. There was also the

question of cross-infection from possibly unscreened patients to

patients with prosthetic material (heart valves). What about other

specialties? Their problem is that there are often not enough

patients that regularly require level 3 care to justify a dedicated

unit. The obvious answer is to pool patients from further afield.

However a catchment area that generates around 1000 cardiac

patients will only generate up to 100 operable oesophageal

cancers. Thus they have to combine with other services.

Oesophageal surgery outcomes improve as do other specialties

like abdominal aortic surgery with increased volume.8 Increased

volume is very apparent in services like cardiac surgery, major

vascular and major cancer and it is probable that the improve-

ments resulting from higher numbers comes not just from an

individual surgeon having more cases, but from the critical care

staff becoming familiar with the complications of the surgery.9

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CRITICAL ILLNESS AND INTENSIVE CARE: I

Can services like cardiac and neurosurgery use combined

facilities? Yes, they can, but each needs to be big enough to be

viable and if they then combine, the unit can get quite large.

Visiting Cornell University, New York you see an ICU on a huge

scale, nearly 60 beds in a single area. It is not possible to run this

as one unit and so the individual services like cardiac become

grouped so that the unit effectively runs as several individual

units. The size tends to be seven to ten beds, which for many

reasons is an optimal number. The new ICU in Leeds though large

in total is built in subunits of seven beds, each run independently.

Infection is a major consideration in organization. Design

comes into this with cubicles, ventilation and so on. In theory all

patients are in ‘virtual isolation’ whether in a cubicle or not. But

spread by touch is not the only consideration. The unit must be

organized in a way that high turnover, ‘screened and clean,’

patients do not come near unscreened or infected patients (who

tend to be the emergency and long term patients).

Thus it is reasonable to have separate units or units within

a unit where this happens. With this approach the unit can orga-

nize areas with open planning and lower staff numbers with

reduced costs. This is also beneficial to patients. After years of

working such a system for cardiac surgery, Aps describes an

‘overnight intensive recovery’, or OIR. He outlines the advantages

to both patients and critical care resources.10 Though this was

originally specific to cardiac services it clearly has a wider appli-

cation once the concept is understood across the hospital services.

It represents a great organizational achievement as it breaks down

many traditional barriers. The concept is that selected elective

cases from a range of specialties, which are expected to recover

within 24 h, can move into a facility organized to respond to their

needs. A prerequisite for an OIR is to have a bed available so that

the surgery can go ahead. This is much easier to plan in such an

area. The next requirement is for high levels of observation for

signs of early complications. Here the design of charts and moni-

tors can be specific for the patient whilst allowing the patient some

comfort and reduced interference. Equipment useful in diagnosis of

acute problems (such as ultrasound to detect bleeding) can be

shared across all the patients and be available 24 hours a day.

Other factors like natural lighting are less important but control of

lighting is appropriate. This area, ‘intensive recovery’ or ‘progress

care unit’ needs to be adjacent to the operating rooms.

Close to this area but not adjacent to the operating rooms is an

area for the higher dependency patients who are expected to

remain for longer periods. Does this sound like the traditional ICU?

The difference is that if the high turnover work is removed from

the ICU the hospital can now provide for the higher dependency

‘sicker’ patients in a single unit usually of ten beds with optimal

use of facilities and staff. The design reflects the patients’ needs

with all infected cases requiring cubicles. ‘Specialist’ patients that

develop multi-system failure can move to the general ICU as their

original pathology becomes relatively less important.

Medical patients requiring ICU would tend to go directly to

this type of area.

It is useful for the less portable diagnostic equipment like CT

scanners to be nearer here, also provision of natural lighting and

facilities for relatives.

Such design and organization can be more imaginative so that

there is a continuum. The recovery area can be close to the

operating rooms, joining recovery is the ‘intensive recovery or

SURGERY 30:5 216

‘progressive care unit’, leading from this is the intensive care

unit. This arrangement can be built as a corridor or a square area.

However it works well in a horse-shoe pattern. The patients go

directly to the correct area and then move as appropriate. This is

very efficient from the point of view of medical and nurse staff-

ing. It is a system that can work in smaller hospitals too.

Typically it will reduce the number of ICU beds that would have

been calculated in the traditional approach.

Hospitals without tertiary work see fewer elective high-risk

patients as they become centralized, for example oesophagec-

tomies and aortic aneurysms. But they will have older patients

having routine surgery and medical admissions. These units

require a different organization. They should be adjacent to the

operating rooms and close to accident and emergency. Cubicles

must be used flexibly and have staff training across a range of

specialties. Here the main problem is the lack of alternatives

within the hospital if they have admissions beyond their

capacity. Thus they need to consider case mix, severity of illness

and have a good triage system at all times. This will ensure that

certain patients are moved to appropriate facilities in other

hospitals, thus allowing local patients to gain admission to ICU

avoiding non-clinical transfers. An important part of this type of

triage model is the involvement of the regional critical care

network. In this way the triage of groups such as paediatrics,

neurosurgery, trauma, advanced respiratory care etc can be pre-

planned which removes stress at work and improves patient

outcomes. Such modernization has been considered to have had

a dramatic effect on critical care organization.11

Paper work and documentation are important with no perfect

system. Observation charts can be designed to focus on certain

patient groups like neurosurgery but general charts need to cover

all systems. Some hospitals feel that one chart should fit all types

of patient, but this leads to bulky charts with time spent on often

irrelevant information. Staff can adapt and there is much to be

said for a thoughtful and relevant process rather than an auto-

matic tick-box exercise. This applies to paper or electronic

systems and medical and nursing staff. The chart exists as

a prompt and a record. Being prompted to record intracranial

pressure in a general surgical patient is not appropriate.

Audit on ICU has progressed significantly. Almost all units in

England and Wales are now signed-up to ICNARC (Intensive

Care National Audit and Research Centre) case-mix programme.

This took on more importance when the critical care minimum

data set (CCMDS) was included in the INARC data. The CCMDS

was developed by the Critical Care Information Advisory Group

endorsed by the Intensive Care Society. These data are required

to generate health resource groups (HRGs) which are needed for

payment by results (PbR). Though not yet implemented, the idea

was to provide information which would reflect the true cost of

caring for patients on ICU. See the article by Whittle & Shelton in

this issue for more information on ICNARC processes.

Staffing

Comprehensive Critical Care provides a foundation on which the

current organization and staffing of intensive care in the UK is

built.4 Many of the recommendations were already happening

but it is re-assuring and points in the right direction. On nurse

staffing it recommends a one-to-one nurse:patient ratio for level

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CRITICAL ILLNESS AND INTENSIVE CARE: I

3 patients, but also stresses the concept of setting nursing levels

to the patient’s dependency rather than a fixed number in all

areas. More contentious is the nursing level required to achieve

this. Many units have six or seven nurses employed per ICU bed

to achieve this, whereas Comprehensive Critical Care states

a ratio of 5.5 nurses per bed. This is discussed in more detail

elsewhere in this edition. Nurse working has moved to 12-hour

shifts, which has not caused any notable improvement or detri-

ment in care,12 although having more nurses does improve

infection control.13 Doctors working on intensive care should all

be specifically trained and no team should cover more than eight

level 3 patients. This is a good aim, but currently there are

insufficient numbers of trained doctors to run all ICUs.

A more pragmatic approach is whether the unit runs an ‘open’

or ‘closed’ system and whether it operates a ‘high’ or ‘low’

intensity staffing system. High-intensity staffing is when the

admitting specialist retains management of the patient but there

is also a senior doctor on the unit full-time who is responsible for

the daily patient care (most of the UK). Low intensity is where

there is no permanent ICU doctor.

An open system is basically as the high intensity but closed is

very different. In a closed system the admitting specialist

discusses the case with the doctor on intensive care. The patient

is admitted under the intensive care doctor. The admitting

specialist then takes a back seat. This is common in Australia

where more doctors are trained in intensive care. There are

a few studies to support this pattern of work. One unit with an

open system but a daily ward round from an intensivist, had

a threefold reduction in mortality, mainly among vascular

patients.7 A similar study focussing on oesophageal surgery

found a decreased length of stay (LOS), decreased costs but no

difference in mortality.14 Daily rounds specifically reduce

complications which adversely affect LOS, re-intubation,

pneumonia and acute renal failure. Further studies in mixed

patient groups show similar results.15 In a review of working

patterns 14 out of 15 units using high-intensity staffing showed

a reduction in mortality.16 One study looking at open versus

closed systems, albeit in a ‘before and after’ design, showed

decreased LOS and complications and lower mortality in the

closed system.17

Working patterns can affect patient outcomes. Having an

intensivist see all admissions (24 hours a day) has a cost, but it

has been shown to reduce mortality and ICU length of stay.18 As

a counter argument though many specialist units have developed

various types of nurse practitioners. One cardiac unit in the UK

has no resident medical staff out of hours. This has been closely

monitored and has not caused any adverse effects on outcomes

(personal communication). Even general units have successfully

introduced nurse practitioners.19 This usefully removes the

burden of too many junior doctors to comply with working time

directives.

Another successful system is having a senior physician,

‘week-at-a-time’ work pattern. In this, the same doctor is

responsible for the daily running of the unit from Monday to

Friday. Each week the doctor changes. It can work in an open or

closed system. Royle described how this was introduced in a way

which allowed comparison of data.20 One ICU continued the

previous system which was open with a different anaesthetist

each session/day. The other unit (in the same trust) had four

SURGERY 30:5 217

anaesthetists with an interest in intensive care working Monday

morning to Friday lunchtime (no nights) on a 4-week rota. Both

units had a similar population. During the 12-month study both

units practised according to the same guidelines introducing

‘ventilator care bundles’, ‘Surviving Sepsis Campaign’ etc. The

authors looked at mortality before and after the year and

between the two units. They found that mortality overall was

reduced in both units but this did not reach significance.

However the ‘week-on’ unit showed a statistically significant

reduction in mortality for ventilated patients.

Units should be multidisciplinary. Radiology and pathology

services are important and add to patient care and teaching. The

most common errors on ICU come from prescribing and having

a pharmacist who specializes in intensive care reduces these

errors. Physiotherapists need to be trained in invasive and non-

invasive ventilation techniques and be available 24 hours a day.

In the UK a nurse:patient ratio is usually 1:1. Some western

countries run different systems. For example, having all the

beds in twin cubicles with one nurse in each cubicle. At first

sight this appears hard for the nurse. However the nurse is fully

supported by pharmacy, physiotherapy, respiratory care tech-

nicians and others. This means the nurse does not have to leave

the room. Movement in and out and therefore infection risk is

reduced.

In summary the ICU location and size should be carefully

planned to reflect the needs of the patient population. The

running of ICU should maximize the potential of its staff. In this

way good results can be achieved even if the medical staff are not

specifically intensive care trained. A

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