Major amputation of the lower limb is one of the most devastating complications of diabetes, and many cases begin as a foot ulcer. General practitioners play an important role through patient education, foot screening and the identification of ‘foot at risk’ patients for a timely referral to a tertiary centre, to reduce the risk of amputation.
INTRODUCTION
Diabetes mellitus is one of the most significant causes
of ill health and disease in Singapore. The lifetime
risk of developing diabetes is one in three among
Singaporeans, and the number of those with diabetes
is projected to surpass one million by 2050.1 This is associated with a projected increased expenditure in
the care of these Singaporeans, which is estimated to
rise to SGD 2.5 billion by 2050.2
DIABETES AND LOWER LIMB AMPUTATION
Major amputation of the lower limb is one of the most
devastating complications of diabetes. Disability is
common after amputation, and removing the individual
from the workforce will cause further economic burden.
Foot ulceration due to neuropathy and repetitive
trauma, complicated by infection and ischaemia, is
the underlying pathway to amputation. The lifetime
incidence of developing a foot ulcer may be as high
as 25% in persons with diabetes3, and 84% of nontraumatic limb amputations are preceded by foot
ulcers4.
Patients with diabetes have a tenfold higher risk of
amputation compared to the general population.5 The prognosis after lower limb amputation is poor, with
one-year mortality of up to 30% in Singapore.6
DIABETIC FOOT WOUND MANAGEMENT
The key to management of diabetic foot wounds is prevention, through education, foot screening and advice on appropriate foot care and footwear.
However, if a wound develops, it should be promptly
referred to a tertiary centre for management by a
multidisciplinary limb salvage team.
In 2009, Fitzgerald introduced the ‘toe and flow’
concept of the diabetic foot team.7 The ‘irreducible minimum’ of the team consists of a vascular surgeon
and podiatrist, with frequent inclusion of additional
specialists as available and necessary.
A systematic review by Musuuza et al. in 2020
reported a reduction in major amputation for diabetic
foot wounds in 94% of the studies, and up to 51%
absolute or 89% relative reduction in major amputation
associated with management by multidisciplinary
teams.8
The team compositions varied between studies, and
included surgeons, physicians and allied health
professionals. Four key clinical tasks commonly
addressed were glycaemic control, local wound
management, vascular disease and infection. The
teams functioned in both inpatient and outpatient
settings.
Multidisciplinary Care for Diabetic Foot Wounds
at Changi General Hospital
The Changi General Hospital (CGH) Vascular and Endovascular Surgery Service has been involved in the
care of diabetic foot wounds for many years. We have a specialised multidisciplinary team caring for these
patients.
In the inpatient setting, the multidisciplinary team conducts ward rounds together every day to ensure optimal medical and wound care. For the past nine years, our service has had a consistent limb salvage rate of more
than 90% at six months post-intervention.
THE CGH WOUND HEALING CENTRE
The CGH Wound Healing Centre provides a one-stop outpatient multidisciplinary service for the evaluation
and management of chronic wounds, including diabetic foot wounds. The centre is helmed by board-accredited
specialists from Vascular Surgery, Orthopaedic Surgery and Plastic Surgery.
Specialised wound care nurses conduct consultations, perform therapy for complex wounds and leverage a
variety of technologies for wound management. Podiatrists perform gait analysis, biomechanical intervention
and pressure offloading, and advise on proper foot care and footwear.
OUR FACILITIES AND CARE TEAM
There are facilities for bedside wound debridement
(Figure 1) and advanced wound care such as the
application of negative pressure wound therapy,
ultrasound and electrical stimulation, and ultrasonic
wound debridement (Figure 2). Diagnostic facilities
such as ultrasonography for arterial disease and
transcutaneous oxygen measurements are also available at our centre.
Our care team is certified by the American Board
of Wound Management (ABWM) as Certified Wound
Specialist Physicians (doctors) and Certified Wound
Specialists (nurses and podiatrists).
Figure 1 The wound examination and dressing
room has seven beds and ample space to allow for
wheelchair access
OUR SERVICES
-
Wound assessment
- Ultrasonography for arterial/venous pathology
- Transcutaneous oxygen measurement
- Conservative sharp wound debridement
- Simple/complex wound dressing
- Compression therapy for venous ulcers
- Negative pressure wound therapy
- Ultrasound and electrical stimulation for wound
healing
- Ultrasonic-assisted wound debridement
- Podiatry for diabetic foot care
Figure 2 Advanced Practice
Nurse Cheng Shuhua performing
bedside ultrasonic wound
debridement on a patient
Background and presentation Mr A is a 63-year-old Indian male with a history of
diabetes mellitus, hypertension and ischaemic heart
disease. He is independent in his activities of daily
living and is community ambulant with no aids. He presented to us with a poor-healing wound on his
right heel associated with increasing swelling and
pain (Figure 3). Figure 3 Infected
right heel wound
before and after
initial debridement He was previously seen by a general practitioner
(GP) and private vascular surgeon who advised him
to go to a public institution for further management,
as primary management with antibiotics and wound
dressing did not improve the situation. He was not
compliant with his diabetes medications. Evaluation
On evaluation, Mr A was found to have right lower
limb chronic limb-threatening ischaemia with an
infected right heel wound and underlying calcaneal
osteomyelitis. He also had poorly-controlled
diabetes with a random fasting glucose of 17.2
mmol/L and HBA1c of 10.3%. Multidisciplinary management
Mr A was reviewed by the endocrinologist for
control of his diabetes and titration of his diabetes
medications. He was also seen by the dietitian and
diabetes nurse educator to reinforce his knowledge
on diabetes control. Figure 4 A clean wound
was achieved after
another two surgical
debridements with partial
calcanectomy performed He underwent right lower limb angioplasty and
debridement of the right heel wound. The infection
was very extensive, involving the plantar fat pad
and plantar fascia. He required another two surgical
debridements and partial calcanectomy to achieve
a clean wound, but the resultant wound was a large
defect in the right heel (Figure 4).
He was reviewed by the Plastic and Reconstructive
Surgery team, and was offered the options of free
flap reconstruction versus fish skin dermal substitute
and negative pressure wound therapy. Mr A opted
for the latter (Figure 5). Figure 5
Application of
fish skin dermal
substitute to right
heel wound Mr A’s care was mainly led by the vascular surgeon,
with contributions from the plastic surgeon,
endocrinologist, infectious disease physician and
allied health professionals including wound care
nurses, podiatrists, physiotherapists and a diabetes
nurse educator.
Patient outcomes
After several surgical procedures for wound
debridement and application of fish skin dermal
substitute, Mr A’s wound healed at seven months
after his first operation (Figure 6). He maintains
functional status and the ability to walk. Figure 6 From left to right: three, six and seven months
after first surgery |
THE ROLE OF GPs IN DIABETIC FOOT CARE
GPs play an important role in the prevention of diabetic foot ulcers through patient and caregiver
education, foot screening, advice on foot care and footwear, and the identification of ‘foot at risk’ patients
for referral to a tertiary centre for further evaluation.
Determining the risk of foot ulcers
The key risk factors for development of foot ulcerations
are:
Loss of protective sensation (LOPS) / peripheral
neuropathy
One or both distal pulses not being palpable /
peripheral arterial disease (PAD)
Presence of foot deformity or callosity
The International Working Group of the Diabetic Foot
(IWGDF) risk stratification system uses these three
factors to advise on foot screening and examination
frequency (Table 1).
Patient and caregiver education
Patient and caregiver education includes the
following advice:9
Do not walk barefoot, in socks without shoes, or in
thin-soled slippers, whether indoors or outdoors
Inspect daily the entire surface of both feet, and
the insides of the shoes that will be worn
Wash feet daily with careful drying, especially in
between toes
Use emollients to lubricate dry skin
Cut toenails straight across
Avoid using chemical agents, plasters or any
other technique to remove calluses or corns
Self-monitor foot skin temperature to identify early signs of inflammation
Wear appropriate footwear that accommodates
the shape of the feet and fits properly, to reduce
plantar pressure and help prevent a foot ulcer
0 | Very low | No LOPS and no PAD | Once a year |
1 | Low | LOPS or PAD | Once every 6-12 months |
2 | Moderate | LOPS + PAD, or OPS + foot deformity, or
PAD + foot deformity | Once every 3-6 months |
3 | High | LOPS or PAD, and one or more of the following:
• History of a foot ulcer
• A lower-extremity amputation (minor or major)
• End-stage renal disease | Once every 1-3 months |
Table 1 The IWGDF risk stratification system9
CONCLUSION
The key to decreasing the incidence of diabetic foot
ulceration is prevention. If a foot ulcer develops, the
patient should be referred to a tertiary centre for
multidisciplinary management to reduce the risk of
major amputation.
The CGH Wound Healing Centre is a multidisciplinary outpatient facility focusing on early intervention and
the fast-track treatment of such patients. Together, we
work towards one goal to improve limb salvage rates
in diabetic patients, and to maintain their functional
status and integrity.
REFERENCES
MOH. Diabetes: The war continues. 2017. https://www.moh.gov.sg/docs/librariesprovider5/war-on-diabetes/wod_public_report.pdf Accessed 6 December 2021
Png ME, Yoong J, Pham TP, Wee HL. Current and future economic burden of diabetes among working-age adults in Asia: conservative estimates for Singapore from 2010-2050. BMC Public Health. 2016;16:153.
Singh N, Armstrong DG, Lipsky BA.Preventing foot ulcers in patients with diabetes. JAMA. 2005;293:217-28.
Brem H, Sheehan P, Rosenberg HJ, Schneider JS, Boulton AJ. Evidence-based protocol for diabetic foot ulcers. Plat Reconstr Surg. 2006;117:7 Suppl193S-209S.
Siitonen OI, Niskanen LK, Laakso M, et al. Lower-extremity amputations in diabetic and nondiabetic patients. A population- based study in eastern Finland. Diabetes Care 1993; 16: 16–20.
Yee Ang, Chun Wei Yap, Nakul Saxena, Lee-Kai Lin, Bee Hoon Heng. Diabetes-related lower extremity amputations in Singapore. Proceedings of Singapore Healthcare 2017, Vol. 26(2) 76–80.
Fitzgerald RH, Mills JL, Joseph W, Armstrong DG. The diabetic rapid response acute foot team: 7 essential skills for targeted limb salvage. Eplasty. 2009; 9: e15
Jackson M, Bryn LS, Suleyman K, Prakash B, Christie MB, Meghan BB. A systematic review of multidisciplinary teams to reduce major amputations for patients with diabetic foot ulcers. J Vasc Surg. 2020;71(4):1433-1446.e3.
Bus SA, Lavery LA, Monteiro-
Soares M, et al. Guidelines on the prevention of foot ulcers in persons with diabetes (IWGDF 2019 update). Diabetes Metab Res Rev. 2020;36(S1):e3269. https://doi.org/10.1002/dmrr. 3269
Dr Lew Pei Shi is a Vascular and Endovascular Surgeon in the Department of General
Surgery in Changi General Hospital (CGH). She has a special interest in the management
of chronic and complex wounds and is an American Board of Wound Management Certified
Wound Specialist Physician. She is part of the core group of surgeons heading the Wound
Healing Centre in CGH.
GPs can call the SingHealth Duke-NUS Vascular Centre for appointments at the following hotlines, or scan the QR code for more information:
Singapore General Hospital: 6326 6060
Changi General Hospital: 6788 3003
Sengkang General Hospital: 6930 6000
KK Women’s and Children’s Hospital: 6692 2984
National Cancer Centre Singapore: 6436 8288