1. Effect of Negative Pressure Incision Care Dressing on wound infection rate in Colorectal Surgery: A Prospective Non Randomized Trial
SM Zaidi, WM Chaudhry, HA Khokhar, H Majeed, SA Khan.
Our Lady Of Lourdes Hospital Drogheda, Ireland.
DISCUSSION
NPWT has been widely used since its introduction in 1971 but there has been little written regarding the potential application of NPWT in closed incisions to prevent wound complications.
Timmers et al have demonstrated increase blood flow, after application of NPWT on healthy skins of volunteers(2), augmenting the efficacy on wound healing.
Stannard et al have shown the effect of NPWT in reducing wound hematoma formation in high energy trauma patients involving lower limbs (3).
Stannard et al have also shown the decrease incidence of seroma formation after lower limb fracture surgery (4).
Kilpadi et al have shown reduced seroma formation in animal models (5).
NPWT may also diminish the risk of wound contamination, since these dressings are applied in sterile environment (6).
With use of NPICT, there is 78% decrease in hospital stay and 76% decrease in cost with acute and chronic wounds (7).
Another perceived advantage of NPWT is splinting of incisions. There is reduction of lateral tension and lines of tension are normalised, similar to pre-incision levels after application of NPWT (8).
Also, NPWT application may keep the deep fat layer in close contact, resulting in decrease shear stress (8) thus decreasing rate of dehiscence and scarring and better cosmesis.
Kaplan et al showed faster recovery of patients who suffered severe trauma with soft tissue defects, if a NPWT device was applied early (9).
This study is the first of its kind, involving general surgical patients.
Selection of patients, considered to be high risk of wound complications was based on established risk factors.
INTRODUCTION
Since its introduction, Negative Pressure Wound Therapy (NPWT) traditionally, has been used mainly to deal with chronic wounds.
Mechanism of action of NPWT includes protection of wound bed (1), splinting of soft tissues (1), reduction of edema, increasing perfusion of wound (2) and enhancing granulation tissue.
Application of Negative Pressure Incision Care Therapy (NPICT) to prevent wound complications is a new concept.
NPICT has also been used successfully in acute wounds of Orthopaedics (3, 4), Gynecological and Cardiothoracic surgery patients to reduce wound infection rates in high risk surgical patients.
There is no data about the use of NPICT in General surgical patients with acute wounds, considered to have high risk of developing wound complications secondary to their co-morbid conditions.
7 days later after removal of NPWT.
(NB: this patient had malnutrition with perforation of malignancy and
associated abscesses formation.)
RESULTS
Mean age in NPICT group was sd (range 45-89) and in control group it was sd (range 46-87).
Male to female ratio was 1:1.06(NPICT) and 1:1.04(Non-NPICT)
In 06(%) patients therapy failed because of technical failure of vacuum application.
There were 42.02% patients with High BMI (>35) in NPICT group and 33.03% in control group (p=0.1442).
Patients with malignancy were 40.57% in NPWT group and 36.6% in control group (p=0.3522).
Emergency surgery was done in 30.43% of cases in NPICT group and 26.78% cases in control group.
Fisher exact test was used to calculate p value.
Risk factors and their relative frequencies in two groups are shown in table (Fig 1).
3 patients (4.2%) in NPICT group and 29 patients (20.4%) in Non-NPICT group developed wound complications [p <0.001, RR=0.68( ), OR=0.14( )]
The LOS increased from 9 ± 3.22 days in the NPICT group and 14 ± 4.31 days for Non-NPICT group.
Complete healing of wounds occurred by 31.1 ± 8.22 days in NPICT group.
Fig. 1: Risk factors and their relative frequencies. (BMI=Body Mass Index)
AIMS
Aim of this study was to assess the use of NPICT in prevention of wound infection and dehiscence, in general surgical patients, who have risk factors and considered to be high risk of developing such complications.
METHODS
A total of 317 patients underwent Laparotomy in a colorectal unit of a regional hospital by a single surgeon and his team
between October 2010 to June
104 (32.1%) patients were excluded on the basis of other complications affecting LOS.
Out of 213 patients included, 71 (33.3%) patients received NPICT, while 142 (66.6%) patients received regular dressings (Non-NPICT group).
NPICT was applied in Operation Theater, immediately after skin closure in conventional way and left in place for 7 days
Study endpoints were rate of 30-day wound infection rate and LOS.
NPWT immediately after application
CONCLUSION
Use of Negative Pressure Incision care therapy (NPICT) significantlty reduces risk of wound infections in high risk colorectal surgical patients thus reducing patients stay and cost. Randomised studies are needed to verify our findings.
REFERENCES
Morykwas MJ, Argenta LC, Sheltonbrown EI et al. Vaccuum assisted closure: A new method for wound control and treatment: Animal studies and basic foundation. Ann Plast Surg 1997;38:
Timmers MS, LeCessie S, Banwell P, Jukema GN et al. The effects of varying degrees of pressure delivered by negative pressure wound therapy on skin perfusion. Ann Plast Surg 2005;55:
Stannard JP, Robinson JT, Anderson ER, McGwin G, Volgas DA, Alonso JE: Negative Pressure wound therapy to treat Hematomas and surgical incisions following high-energy trauma: J Trauma 2006;60:
Stannard JP, Atkins BJ, O’Malley D, Singh H, Bernstein B, Fahey M,Masden D, Attinger CE.Use of negative pressure wound therapy on closed surgical incisions.A case series.Ostomy wound Manage 2009;55:58-66
Kilpadi DV, Cunningham. Wound 2011;2-9
Gomoll AH, Lin A, Harris MB. Incisional vacuum-assisted closure therapy. J Orthop Trauma 2006;20(10):
Townsend CM, Beauchamp RD, Evers BM, Mattox KL. Sabiston Text book of Surgery 18th Edition; Ch 8 p213
Wilkes RP, Kilpadi DV, Zhao Y, Kazala R, McNulty A. Closed Incision Management with negative pressure wound therapy (CIM):Biomechanics. Surg Innov. XX(X)1-9
Kaplan M,Daly D, Stemkowski S (2009) Early intervention of negative pressure wound therapy using vacuum-assisted closure in trauma patients:Impact on hospital length of stay and cost. Adv Skin Wound Care 22(3):
Risk Factors
NPWT
Control
P value
BMI > 35
42.02 %
33.03 %
0.1442
Malignancy
40.57 %
36.60 %
0.3522
Emergency Surgery
30.43 %
26.78 %
0.3576
Atherosclerosis
26.08 %
17.85 %
0.1290
Smoker
8.69 %
16.07 %
0.3710
Diabetes Mellitus
7.24 %
10.71 %
0.3086