Guidelines on the facilities required for minor surgical procedures and minimal access interventions
Article Outline
- Summary
- Introduction
- History of hospital operating theatres
- Recommendations
- Acknowledgements
- Conflict of interest statement
- Funding sources
- References
- Copyright
Summary
There have been many changes in healthcare provision in recent years, including the delivery of some surgical services in primary care or in day surgery centres, which were previously provided by acute hospitals. Developments in the fields of interventional radiology and cardiology have further expanded the range and complexity of procedures undertaken in these settings. In the face of these changes there is a need to define from an infection prevention and control perspective the basic physical requirements for facilities in which such surgical procedures may be carried out. Under the auspices of the Healthcare Infection Society, we have developed the following recommendations for those designing new facilities or upgrading existing facilities. These draw upon best practice, available evidence, other guidelines where appropriate, and expert consensus to provide sensible and feasible advice. An attempt is also made to define minimal access interventions and minor surgical procedures. For minimal access interventions, including interventional radiology, new facilities should be mechanically ventilated to achieve 15 air changes per hour but natural ventilation is satisfactory for minor procedures. All procedures should involve a checklist and operators should be appropriately trained. There is also a need for prospective surveillance to accurately determine the post-procedure infection rate. Finally, there is a requirement for appropriate applied research to develop the evidence base required to support subsequent iterations of this guidance.
Keywords: Minor surgery, Operating theatres, Primary care, Surgical site infection, Ventilation
Introduction
There have been many changes in healthcare delivery in recent years, including the delivery of surgical services in primary care or in day centres, previously provided by acute hospitals. Also, some minor surgical procedures continue to be performed outside the conventional operating theatre.
A recent survey of operating theatre ventilation facilities for minimally invasive surgery in the UK found that most procedures were carried out in areas without specialist ventilation and/or in facilities that are often referred to as ‘treatment rooms’.1 However, there is a paucity of evidence on whether or not procedures carried out under these conditions are associated with increased infection rates, specifically surgical site infection (SSI).
Guidelines to minimize SSI by identifying interventions during the pre-operative, operative and post-operative phases have been published.2 Although these guidelines apply to all surgical or operative interventions, they do not address the physical conditions under which minor surgical procedures – those carried out under local anaesthesia and that are superficial, and minimal access interventions (MAIs), i.e. therapeutic or diagnostic procedures that are not considered major in terms of the size of the operative site – should take place. Nonetheless, there is confusion among infection prevention and control personnel, operators and others as to what facilities and practices are required when minor surgical procedures and MAI are carried out in the acute hospital sector and elsewhere, such as in primary care.
History of hospital operating theatres
Over the centuries, surgeons have moved from operating under primitive conditions to an environment which is ventilated to specific high standards and considerably advanced from that of their predecessors. The practice of surgery demands the training of surgical trainees in the use of masks, sterile clothing and the need to minimize movement into and within the operating theatre.3 There is also emphasis on minimizing the duration of each procedure as it is accepted, based on evidence, that prolonged procedures carry increased risk for SSI.4
Specialized ventilation systems in operating theatres
Originally, powerful extract ventilation was provided for operating theatres to remove steam from boiling water ‘sterilizers’, pulling in air from surrounding areas (i.e. the theatre was at negative pressure), but this led to infections caused by airborne bacteria being drawn in from adjacent wards. With the general provision of clean air under positive pressure, clean wound infection rates fell by a factor of 10.5, 6, 7
The principle of modern conventional theatre ventilation is to remove airborne contamination generated in the theatre and to prevent the ingress of possibly contaminated air from the surrounding areas. This is achieved by actively supplying relatively clean air into the theatre faster than excess air can be passively removed.
The air escapes through pressure release dampers and any gap in the fabric of the theatre (e.g. around doors) and, in flowing outwards, it prevents any air from surrounding areas flowing inwards.
The main source of airborne contamination is the skin of those moving inside the theatre, i.e. the staff.8 This is diluted by the air supplied to the theatre, with air then flowing out to less sensitive areas such as corridors, carrying the contamination away with it.8 A classic study of operating theatre ventilation found that counts of airborne microbes increased with the degree of movement and numbers of personnel within the theatre.9 It was shown later that airborne skin squames carrying micro-organisms in a ‘raft-like’ fashion are shed from the skin surface; during modest activity, humans can shed microbe-carrying skin scales yielding up to 10,000 colony-forming units (cfu) every minute.10, 11, 12
The importance of ventilation in controlling airborne contamination was shown in an early study in England where the comparative rates of infection in hospital ranged from 2% to 7% and the cut-off between a low and high rate was an air-count of 5 cfu/ft3 referred to in the so-called Lidwell Report, the forerunner of Health Technical Memorandum 2025, ‘Ventilation in healthcare premises’.13, 14
In ‘clean’ surgery, surgical sites can be exposed to airborne bacteria, either directly into the wound or indirectly by microbes settling onto surgical/operative instruments which will then, on use, transfer this contamination to the surgical site. This latter route probably accounts for the majority of airborne bacteria in a surgical site or wound.15 The smaller the incision, such as during laparoscopy, the greater will be the proportion of bacteria that enter the wound via indirect airborne sources. Thus instrument contamination contributes proportionally more to surgical site contamination in this scenario.
The critical areas within the operating theatre suite are the operating theatre itself and the preparation room, where sterile instrument packs may be opened and exposed to the air before use. The soiled utility room is under negative pressure (i.e. inward airflow) so that it does not contribute to airborne contamination in theatre.
There is a need to define procedures in terms of the susceptibility of the surgical or operative site to contamination and to define the basic physical requirements of facilities in which many minor surgical procedures and MAI may be carried out.
Aetiology of post-operative infections in minor procedures and MAI
In the National Institute for Health and Clinical Excellence (NICE) guidelines on SSI, no distinction is made between minor surgical procedures, MAI and conventional surgical operations.2 However, it is not always clear what is meant by minor surgical procedures or MAI and the individual perception of this may vary according to background and professional practice. Laparoscopic procedures are associated with lower infection rates than those after open procedures but patients who undergo laparoscopic procedures may be pre-selected and have a lower risk of infection as more complicated cases are carried out as conventional surgical operations.16, 17
Surveillance data of orthopaedic procedures from the Health Protection Agency revealed that Staphylococcus aureus accounted for 39–44% of the bacteria responsible for SSI in these procedures followed by Enterobacteriaceae in 14–19% of cases.18 The bacteria recovered from specimens taken from infected wounds following laparoscopic abdominal surgery, minor hand surgery or day surgery, largely reflect the endogenous flora of both patients and staff, and appear to be no different from those following conventional surgical operations.19, 21 For example, S. aureus was responsible for 44% of infections of the hand and Pseudomonas aeruginosa and other Gram-negative bacilli are more likely to be responsible for infections arising from laparoscopic gastrointestinal procedures.19, 20 Therefore there does not appear to be any difference in the causative microbes of post-operative infection whether carried out as a conventional surgical operation or as an MAI/minor surgical procedure.
Interventional radiology
The major recent developments in radiology/imaging include therapeutic interventions in the vascular and non-vascular arenas. Interventional radiology was originally pioneered by Charles Dotter (1920–1985) who saw the potential for treatment, as well as diagnosis, with the use of catheterization.
Endovascular procedures are now often considered before open surgery and these techniques can be used in the management of a range of cerebrovascular, cardiovascular and oncological conditions. Biocompatible materials, e.g. stents including those covered with graft material used in the modern management of aortic aneurysms, coils, particles and inferior vena cava filters, may be implanted. Some procedures require access to the arterial system by an arteriotomy, but the majority can be performed by a percutaneous approach.
In the non-vascular arena, there are a variety of procedures, such as computed tomography and ultrasound-guided tumour ablation instead of open surgery and osteoplasty which instills cement into weakened bone without the need for an operative approach. A variety of percutaneous catheters and stents are used for drainage of obstructed urinary and hepatobiliary systems.
Interventional radiology is likely to be the initial treatment for many diseases in preference to open surgery in the future.22 To date, anecdotal reports seem to indicate that infection rarely occurs following these procedures. Every effort is used to maintain sterility, including only opening the intervention kit when it is about to be used, but the ventilation and other facilities in most interventional radiology departments are not as yet equivalent to those of an operating theatre. It is recommended that endovascular aneurysm repair should only be performed in a dedicated endovascular suite of operating theatre standard with appropriate ventilation and support facilities, because of the severe consequences when infection complicates this procedure.23
Surgical issues
The operational standards under which minor surgical procedures or MAI are carried out in the outpatients department, in the emergency department or elsewhere outside the theatre have not been defined but should maximize patient safety while being feasible in terms of facilitating access to clinically required procedures. There is increasing emphasis on some surgical procedures being carried out as day procedures; for some, a specialist ventilated theatre is not currently used, e.g. excision of nail bed and vasectomy.24 A current trial of patients undergoing vasectomy in conventional operating theatres and in procedure rooms with no mechanical ventilation shows no difference to date in post-procedure infection rates but this trial is ongoing (M. Nevill, personal communication). The pressure to carry out more procedures in primary care, where it may be cheaper, and the obvious advantages for some patients in terms of ease of access mean that more procedures may take place outside hospitals and under non-ventilated conditions. For example, it is suggested that a variety of procedures such as carpal tunnel decompression, the removal of a ganglion from the dorsum of the wrist, and haemorrhoid injections may be carried out by general practitioners with enhanced surgical experience in a ‘modified treatment room/operating theatre’.25 Although this guideline is helpful in indicating which procedures can usually be carried out in primary care, the precise definition of this type of facility remains unclear.
In addition, the unexpected may occur, for example the removal of an apparent groin lymph node in a hospital operating theatre may subsequently become a hernia repair which requires the facilities of an operating theatre.
The use of aseptic techniques with the appropriate facilities is especially important in those areas of surgery where the consequences of infection can be devastating, for example orthopaedic surgery resulting in an infected implant, or ophthalmic surgery resulting in endophthalmitis. However, intravitreous injections such as in the treatment of macular degeneration, are carried out in treatment rooms with or without specialist ventilation, and the risk of endophthalmitis, when it occurs occasionally, is related to suboptimal technique.26, 27
Basis for design specifications for minor surgery and MAI, including interventional radiology
Health Technical Memoranda in the UK seek to define the optimum parameters in which various forms of healthcare delivery should be undertaken. There is a range of ventilation options available, depending on whether a day case theatre, treatment room, endoscopy room, a conventional or an ultraclean theatre is being considered. In all cases the primary requirement is to protect the patient from preventable infection. There is also a need to control the exposure of staff to waste anaesthetic gases, where present, and to ensure that staff work in comfortable conditions.
Traditionally UK operating theatres have been ventilated at ∼20 air changes per hour, an ‘air change’ occurring when a volume of air equivalent to the volume of a room has been supplied to or extracted from that room, and the operating theatre is maintained at a positive pressure to surrounding areas. This air change rate has been shown to be sufficient to dilute contaminants within the theatre, with the resulting positive pressure ensuring that contaminants from outside do not enter.13
Current guidelines recommend a design ventilation rate of 25 air changes per hour for new conventional operating theatres.28 The supply air should be filtered to at least EN 779 F7 standard (i.e. 80–90% efficiency against a test aerosol with particles of 0.4 μm) and a positive pressure differential of 25 Pa with respect to outside air.13 The performance of the ventilation system is acknowledged to deteriorate over time, but as long as at least 18 air changes are achieved it will remain acceptable. The ventilation requirements for ultraclean theatres are much greater in terms of a more organized air flow at the operating site with the supply air being high efficiency particulate air (HEPA)-filtered.
Portable HEPA-filtered auxiliary ventilation units are available, and, when incorporated into an instrument trolley, may provide the equivalent of ultraclean air quality in an ultraclean ventilated theatre but over surgical instruments on the trolley (M.J. Thomas and C.A. Mackintosh, personal communication). Freestanding portable HEPA-filtered directional auxiliary ventilation units have been evaluated.29 Their effectiveness is likely to be influenced by their position and direction relative to the operating site and discipline of the operating staff.
In rooms where anaesthetic gases may be used, e.g. interventional radiology, a minimum of 15 air changes per hour is required for the removal of airborne chemicals.28
In designing surgical and operative facilities, there are many other issues apart from ventilation to be considered. These include sterile pack storage facilities, separating where possible clean and dirty facilities, the type and location of the scrub and the disposal of excised human tissue and surgical waste.
Recommendations
General principles
The primary objective in formulating standards for facilities is to protect patients from surgical site and other infections. The removal of anaesthetic gases and the provision of comfortable facilities for healthcare staff are also important and should be considered.
It is recognized that the risk of infection will vary according to the procedure and the patient. Even where there is a low risk of infection after a specific procedure, in some circumstances the consequences may be disproportionately serious, for example, infection after arthroscopy resulting in septic arthritis. Consequently, such factors should be considered in deciding where a procedure should be carried out and under what conditions, i.e. conventional operating theatre standards or those outlined below. Here we make recommendations on the design of new facilities to be used for the carrying out of MAI, including interventional radiology, and minor surgical procedures to minimize post-procedure infections. We also hope to raise awareness of all healthcare staff and patients of the importance of infection prevention.
We recognize that many minor surgical procedures in particular are currently being undertaken in facilities that do not meet these standards, and usually without reported adverse consequences in terms of increased infections. However, in response to the changing delivery of healthcare, increasingly in the non-acute hospital sector, and in response to requests for guidance, we have produced the following guidelines. These are based on best practice, evidence and current guidelines where available and appropriate, and expert consensus to primarily provide sensible and feasible advice. For existing facilities, consideration should be given to using these recommendations to improve facilities in part or in full over time.
Definitions
CT, computed tomography. aMainly derived from recommendations/discussions in References 24 and 25.Table I. Examples of minor proceduresa under various surgical disciplines that may be performed outside a ventilated operating theatre
Surgical discipline Procedure Breast Percutaneous core biopsy
Vacuum-assisted excision biopsyEar, nose and throat Cauterization of nasal septum
Polypectomy of internal nose
Manipulation of fractured noseGeneral Trans-anal excision of lesion of anus
Haemorrhoid injections and haemorrhoidectomy
Excision of epidermoid cysts, lipoma (<2 cm), basal cell carcinoma and ‘small bumps and lumps’
Hydrocele aspirationGynaecology Endometrial biopsy
Colposcopy
Diathermy or laser treatment of cervical lesions
Marsupialization of Bartholin’s cyst
Insertion of intrauterine device
Vacuum aspiration, and dilatation and evacuation termination of pregnancyOphthalmology Excision, biopsy or cauterization of eyelid, e.g. chalazion
Laser iridotomy
Intravitreal injections
Lacrimal sac washouts
Subconjunctival injectionsOrthopaedic Excision of ingrown toe nail
Intra-articular injection
Carpal tunnel surgeryVascular surgery Varicose vein injection, sclerotherapy, laser treatment or radiofrequency ablation Other Liver, renal and bone marrow biopsy
Caudal block
Endoscopy via natural orifices, e.g. cystoscopy and gastroscopy
Vasectomy
Pleural drain insertion
Radiologically guided CT or ultrasound drain insertion and biopsies
Facilities specifications
This should preferably be made from non-porous material that can be easily cleaned. Suspended ceilings should not be installed in new facilities.
These should be made from non-porous/monolithic material that can be easily cleaned and occasionally disinfected.
These should be non-openable where specialist mechanical ventilation is provided.
Where there is natural ventilation using a window that can be opened, there must be a fly screen to prevent the ingress of insects.
Where windows are present, these must not compromise patient privacy.
These should be self-closing with a vision panel (with laser protection where appropriate) to facilitate observation of procedures and the movement in and out of the operating room. However, this has to be balanced with the necessity for patient privacy.
Floors should be easily cleaned and disinfected according to local policies, and be durable and strong enough to support the machinery that will be necessary in some operative facilities.
Coving is desirable to facilitate cleaning, contain spills and to avoid damage.
Single-use instruments may be preferable and their use is encouraged if it is difficult to comply with the requirements for the appropriate decontamination and storage of reusable instruments. Also, for minor procedures in primary care, single-use items eliminate the increasingly rigorous requirements to decontaminate surgical instruments to a standard that would be difficult to comply with outside specialized sterile supply departments.30, 31
Dedicated secure facilities should be provided for the storage and collection of re-usable instruments if preferred, including endoscopes and their accessories (which require pre-cleaning in a separate sink), to ensure their safety and to avoid damage to the instruments themselves.
There should be adequate storage space for instruments with due regard to the range of procedures carried out and the throughput of patients.
The design should minimize the deposition of dust, including appropriate racking or shelving.
Unlike for conventional operating theatres, a separate area for the laying up of instruments is not required, but instruments should only be laid up as required and not in advance.
These may be within the operative facility, but, if within the operating room/theatre, should be located such that instruments do not get splashed and should be separate from basins used for other purposes.
Taps or faucets should be hands-free.
Disposable towels should be used.
The facilities and the procedures for the safe disposal of waste should comply with the current guidelines for holding waste prior to collection/disposal.32
A separate secure area, inside or outside the operative facility, e.g. a lockable bin, should be provided.
It is recommended that new facilities be designed to achieve 15 air changes per hour, as required for the removal of airborne chemicals/anaesthetic gases and which we believe is microbiologically adequate in this setting.28 Such a specification is required because of the need to prevent the deposition of airborne contamination on to items that may be introduced into the patient, especially where there is implantation of sterile prosthetic devices such as stents, and a need occasionally to convert to an open procedure. Where there is a perceived increased risk of infection due to the complexity of the patient or the procedure, a risk assessment should be carried out to determine whether the procedure should be undertaken in a theatre in the operating theatre suite.
Supply air should be filtered by an EN 779 F7 filter (see above and Reference 13) for new facilities.
There should be a pressure differential of ≥5 Pa positive pressure between the operating facility and the surrounding area when constructing new facilities.
Natural ventilation, including the presence of opening windows but with a fly screen, is acceptable.
For mechanically ventilated facilities, these should be within the standard range, i.e. 18–22 °C with a relative humidity of 20–60% unless clinical considerations deem otherwise.
Where the operating facility has specialist mechanical ventilation to the standards above, there should be a clear indication to those carrying out the procedure (i.e. within the room such as part of a surgeon’s panel in a conventional theatre) that the ventilation is functioning correctly.
This should be adequate for the task to be undertaken in the facility.
Where MAIs with general anaesthesia are undertaken, 15 air changes per hour are required, similar to that specified for anaesthetic rooms in conventionally ventilated theatre suites, to minimize staff exposure to anaesthetic gases.28
Access to Picture Archive and Communications Systems (PACS) is required to optimize the quality and safety of patient care.
There should be adequate facilities and space for the collection and storage of specimens, with temperature-controlled conditions, for important or key specimens.
All facilities should have emergency lighting in the case of a loss of power supply and should comply with relevant health and safety recommendations.
Professional practice
If the hands of the operator are not visibly dirty, alcohol hand rubs or equivalent may be used between cases. However, a conventional surgical scrub is indicated at the start of a list, i.e. before the first case or procedure. Sterile gloves and a plastic apron are the minimum personal protective equipment requirement for carrying out minor surgical procedures. However, full precautions, including fresh sterile gowns for each case, are required for MAI, for minor surgical procedures if a sterile device is being implanted and when there is a risk of significant post-procedure infection, or if there are other factors predisposing to infection.
Masks are not usually required except when a sterile device is being implanted, or when there are other issues predisposing to infection. However, face protection (e.g. mask with eye protection) for operators and other staff who may be affected is required, if splashing is likely. Further details on pre-, peri- and post-operative interventions to minimize SSI can be accessed elsewhere.2
All surgical procedures should involve a checklist. Those involving general anaesthesia should be modelled on the World Health Organization checklist for safe surgery (http://www.who.int/patientsafety/safesurgery/tools_resources/SSSL_Checklist_finalJun08.pdf) to include aspects of mechanical theatre ventilation, e.g. checking that the ventilation is working, in facilities for MAI. Modifications to these may be made for MAI and minor surgical procedures as appropriate.
Training and education
Facilities need to meet the educational needs of students, doctors in training and other healthcare workers, such as those related to understanding infection and sepsis. All staff involved in MAI and minor surgical procedures must be able to provide evidence of competency in aseptic technique and in their knowledge and understanding of the facilities that are provided, e.g. ventilation, safe disposal of waste, etc. Although outside the scope of this document, practitioners carrying out MAI and minor surgical procedures should be competent to do so with appropriate mandatory training and ongoing continuous professional development.
Research and audit
As there is an absence of good data on the risk of infection after MAI and after most minor surgical procedures, prospective surveillance of post-procedure infections is required. Audit is necessary, and should include, as minimum, re-admission rates for healthcare-associated infection. There should be access to the results of research and audit, and research in primary care is essential to underpin improvements in patient care. Appropriate support and funding to develop the evidence base is required to support subsequent iterations of this guidance.
Acknowledgements
We wish to acknowledge the support and help of S. Hollinshead at the Healthcare Infection Society throughout the development of these guidelines. We are also grateful to the following individuals who contributed to the initial meeting: J. Hood, M. Kelsey, M. Kiernan, D. Tucker and H. Osborne. We also wish to thank those individuals and organizations that provided helpful and valuable feedback on earlier drafts.
Conflict of interest statement
H.H. has recently been in receipt of research funding from Steris Corporation, 3M, Inov8 Science, Pfizer, Wyeth & Cepheid. He has also received lecture or consulting fees from 3M, Novartis & Astellas. The following have no conflicts of interest: J.E.C., A.S., M.T., A.M.B., P.H., P.J., C.M.
Funding sources
The Healthcare Infection Society.
References
- Survey of operating theatre ventilation facilities for minimally invasive surgery in Great Britain and Northern Ireland; current practice and considerations for the future. J Hosp Infect. 2005;61:112–122
- National Collaborating Centre for Women’s and Children’s Health. Surgical site infection. Prevention and treatment of surgical site infection. London: National Institute for Health and Clinical Excellence; October 2008.
- . Identifying patients at high risk of surgical wound infection. A simple multivariate index of patient susceptibility and wound contamination. Am J Epidemiol. 1985;121:206–215
- Surgical site infection prevention: the importance of operative duration and blood transfusion – results of the first American College of Surgeons–National Surgical Quality Improvement Program Best Practices Initiative. J Am Coll Surg. 2008;207:810–820
- . Control of wound infection in a thoracic surgery unit. Lancet. 1955;2:786–794
- . Postoperative wound infection. Surg Gynecol Obstet. 1956;103:257–262
- . Humphreys H on behalf of the Hospital Infection Society Working Party on Infection Control and Operating Theatres. A UK historical perspective on operating theatre ventilation. J Hosp Infect. 2002;52:77–80
- . Sepsis of surgical wounds. In: Willis RRO, Blowers R, Garrod LP, Shooter RA editor. Hospital infections; cause and prevention. 2nd ed.. London: Lloyd-Luke; 1966;p. 77–115
- Bourdillon RB, McFarlane AM, Thomas JC. Airborne bacteria in operating theatres. MRC Special Report Series 1948;262:241–253.
- . Dispersal of Staphylococcus aureus by patients and surgical staff. Lancet. 1965;i:480–483
- . The dimensions of skin fragments dispersed into the air during activity. J Hyg (Camb). 1978;81:471–479
- . Aerial dissemination of Staphylococcus aureus by hospital patients: causes and prevention. Prevention. 1972;1:43–50
- Lidwell OM, ed. Ventilation in operation suites. Report of a Joint DHSS/MRC Working Party. Department of Health and Social Security. London: HMSO; 1972.
- Department of Health Estates Office. Health Technical Memorandum 2025. Ventilation in healthcare premises, Vol. c, Validation and verification. London: HMSO; 1995.
- . The importance of airborne bacterial contamination of wounds. J Hosp Infect. 1982;3:123–135
- . Laparoscopic use and surgical site infections in digestive surgery. Ann Surg. 2008;247:627–632
- Impact of laparoscopic colorectal resection on surgical site infection. Ann Surg. 2009;249:77–81
- . Sixth report of the mandatory surveillance of surgical site infection in orthopaedic surgery. April 2004 to March 2010 London: HPA; December 2010;
- . The need for antibiotic prophylaxis in elective laparoscopic cholecystectomy. A prospective randomized study. Arch Surg. 2000;135:67–70
- . Epidemiology of bacterial hand infections. Int J Infect Dis. 2006;10:315–319
- Surgical site infections in day surgery settings. Surg Infect. 2006;7:S-121–123
- . Interventional radiology procedures: addressing the needs of the cardiovascular patient. Rev Cardiovasc Med. 2008;9(Suppl. 1):S35–43
- . Delivering an endovascular aneurysm repair (EVAR) service. London: Medicines and Healthcare products Regulatory Agency (MRHA); December 2010;
- . BADS Directory of procedures. 3rd ed.. London: BADS; 2007;
- . Standards and recommendations for surgery in primary care. London: APP; 2008;
- Evolving guidelines for intravitreous injections. Retina. 2004;24:S3–19
- . Pegaptanib for neurovascular age-related degeneration. N Engl J Med. 2004;351:2805–2816
- . Health Technical Memorandum 03-01; Part A, Specialised ventilation for healthcare premises. London: DoH; 2007;
- A mobile laminar airflow unit to reduce air bacterial contamination at surgical area in a conventionally ventilated operating theatre. J Hosp Infect. 2007;66:313–319
- . Decontamination of re-usable medical devices in primary, secondary and tertiary care sectors (NHS and Independent Providers). London: DoH; 2007;
- . Health Technical Memorandum 01-05. Decontamination in primary care dental practices. London: DoH; 2009;
- . Health Technical Memorandum 07-01. Safe management of healthcare waste. London: DoH; 2011;
PII: S0195-6701(11)00444-0
doi:10.1016/j.jhin.2011.11.010
© 2011 The Healthcare Infection Society. Published by Elsevier Inc. All rights reserved.
