Comparative study of the microvascular blood flow in the intestinal wall, wound contraction and fluid evacuation during negative pressure wound therapy in laparostomy using the V.A.C. abdominal dressing and the ABThera open abdomen negative pressure therapy system

Pilot assessment of the effect of negative pressure wound therapy on microperfusion of chronic and acute wounds

BACKGROUND

Negative pressure wound therapy (NPWT) has been established over years for treatment of chronic and complex wounds.

OBJECTIVE

Aim of this study was to investigate the effect NPWT on the microperfusion.

METHODS

Prospective single centre analysis of patients treated with NPWT due to acute (ACUTE) wounds after fasciotomy or patients with chronic wounds (CHRONIC) due to a chronic limb threatening ischemia was performed. NPWT was conducted through a three days sequence with a negative pressure of -120 mmHg. Before after and during the entire period of therapy the microperfusion was assessed (O2C™, LEA Medizintechnik).

RESULTS

Comparison of the perfusion values of 28 patients (CHRONIC/ACUTE 5/23, women/men 8/20) before and after the NPWT sequence showed a non-significant improvement in the CHRONIC group (supine position: p = 0.144, elevated position p = 0.068) and a significant decrease in the ACUTE group (supine position p = 0.012, elevated position p = 0.034). This effect could also been demonstrated during the NPWT over time (CHRONIC: supine position: p = 0.320, elevated position: p = 0.053, ACUTE: supine position: p = 0.021, elevated position: p = 0.012).

CONCLUSION

Microperfusion measurements showed alterations and differences in wound bed perfusion of acute and chronic wounds; acute wounds tended to a decrease of blood flow, whereas this effect was not seen in chronic wounds in peripheral artery disease.

Successful improved peripheral tissue perfusion was seen in patients with atherosclerosis after 12 months of treatment with aged garlic extract

Patients with arteriolosclerosis have impaired microvascular perfusion leading to impaired wound healing. Aged garlic extract has shown to have a positive impact on vascular elasticity. The present study aimed to assess the effect of long‐term treatment with AGE on peripheral tissue perfusion in patients with confirmed atherosclerosis. Ninety three patients with a CT‐scan confirmed coronary artery arteriolosclerosis were randomised in a double‐blind manner to placebo or 2400 mg AGE daily for 1 year. Peripheral tissue perfusion was evaluated at 0‐ and 12‐months using Laser Speckle Contrast Imaging. Measurement of post occlusive reactive hyperemia (PORH) and cutaneous vascular conductance (CVC) using acetylcholine iontophoresis (Ach) was conducted. After 12 months a significant increase of 21.6% (95% CI 3.2%‐40.0%, P < .05) was seen in the relative change of PORH in the AGE compared with the placebo group. The same response was seen for CVC and Ach with an increase of 21.4% (95% CI 3.4%‐39.4%, P < .05) in the AGE group compared with the placebo group. Aged garlic extract regenerated peripheral tissue perfusion and increase microcirculation in patients with arteriolosclerosis. Adequate peripheral tissue perfusion and tissue oxygen tension are important prerequisites for successful tissue repair. Restored microcirculation in patients could hypothetically facilitate wound healing.

The Effect of Negative Pressure in the Abdominal Cavity With Suprasorb CNP on Abdominal Organs-An Experimental Study

Since the introduction of negative pressure therapy of the abdomen, care has been taken to protect the intestine from the effects of negative pressure in order to avoid impairments of abdominal organs. As an alternative to the widespread AB-Thera^R system (KCI, San Antonio, Texas, USA), the different concept of Suprasorb CNP^R (Lohmann & Rauscher, Austria-Germany) was introduced by the producer with the premise of achieving a better therapeutic effect. Due to numerous pores of the film, the effects of the negative pressure are brought to the surface of the intestinal organs and these effects were tested on seven experimental animals. Particular attention was paid to the small intestine, colon, liver, and pancreas. Over 8 h continuously, three animals were tested with −80 mmHg, 4 with −60 mmHg. The results showed no macroscopic pathological changes. The histological results showed borderline changes in the small intestine and colon with −80 mmHg application, minimal or none with −60 mmHg. The liver and pancreas were found free of pathological changes. For use on human organs, the intra-abdominal application of −60 mmHg for the Suprasorb CNP system is proposed as the standard.

Intrauterine negative-pressure therapy (IU-NPT) to treat peritonitis after caesarean section

Objectives

We describe the first application of intrauterine negative-pressure therapy (IU-NPT) for an early rupture of a uterine suture after a third caesarean section with consecutive peritonitis and sepsis. Because all four quadrants were affected by peritonitis, a laparotomy was performed on the 15th day after caesarean section. Abdominal negative-pressure wound therapy (A-NPWT) of the open abdomen was initiated. During the planned relaparotomy, a suture defect of the anterior uterine wall was identified and sutured. In the second relaparotomy, the suture appeared once more insufficient.

Case presentation

For subsequent IU-NPT, we used an open-pore film drainage (OFD) consisting of a drainage tube wrapped in the double-layered film. The OFD was inserted into the uterine cavity via the uterine defect and IU-NPT was established together with A-NPT. With the next relaparotomy, local inflammation and peritonitis had been resolved completely. IU-NPT was continued transvaginally, the uterine defect was sutured, and the abdomen was closed. Vaginal IU-NPT was also discontinued after another eight days.

Conclusions

By using IU-NPT, local infection control of the septic focus was achieved. The infectious uterine secretions were completely evacuated and no longer discharged into the abdominal cavity. As a result of the applied suction, the uterine cavity collapsed around the inlaid OFD. The total duration of IU-NPT was 11 days. The uterine defect was completely closed, and a hysterectomy was avoided. The patient was discharged four days after the end of IU-NPT. IU-NPT follows the same principles as those described for endoscopic negative-pressure wound therapy of the gastrointestinal tract.

Combined surgical and negative pressure therapy to treat multiple enterocutaneous fistulas and abdominal abscesses: A case report

Introduction

We report the case of a successful management with combined aggressive surgery and negative pressure therapy, to treat a severely ill-septic patient, affected by multiple chronic enterocutaneous fistulas.

Presentation of case

A 26-year-old female patient presented with multiple pelvic and intra-abdominal abscesses, enterocutaneous fistulas and central venous catheter-related bacteraemia in extremely poor general conditions.The patient underwent both an abdominal CT which showed multiple digestive loops stuck and apparently fistulised and an abdominal-pelvic MRI, confirming the CT findings, and demonstrating a third fistula involving the Pouch and responsible for a pelvic and retroperitoneal chronic abscess.Given the patient's septic condition, despite several attempts of conservative therapies, an aggressive surgical approach was adopted.After temporary abdominal wall closure, the patient underwent Vacuum Assisted Closure therapy in order to close the abdominal wall and drain the residual abscess. The patient was discharged at the 35th post-operative day in good general conditions.

Discussion

This case is about a complex, long-lasting clinical scenario, progressively leading a young woman to death despite several attempts of conservative therapy, sometimes allowed to treat enterocutaneous fistulas. The use of negative pressure therapy to manage open abdomen is still controversial. Patients affected by enterocutaneous fistulas are in need of adequate nutritional support due to their hypercatabolic state, secondary both to the fluid loss and the concomitant inflammatory status.

Conclusion

When conservative management fails and the patient shows septic complications, a multidisciplinary aggressive approach, including surgery, negative-pressure therapy and hyperbaric oxygen therapy is required to treat this life-threatening condition.

Rare case of adhesive large bowel obstruction in acute burn patient: management of open abdomen with ABTHERA ADVANCE™ Open Abdomen Dressing

Large bowel obstructions (LBO) are rarely caused by adhesions. Surgical management of this condition may require an open approach but closure may not always be possible. There are many temporizing measures in clinical use; however, the ABTHERA ADVANCE™ Open Abdomen Dressing has demonstrated significantly improved outcomes compared to other negative pressure wound therapy dressings. There are few cases in the literature documenting adhesive LBO and none in an acutely unwell burn patient whose abdomen subsequently required the ABTHERA ADVANCE™ Open Abdomen Dressing. We emphasize the importance of considering adhesive LBO as a differential in bowel obstruction and highlight a novel but effective way of managing it in our unique case.

Aged garlic extract preserves cutaneous microcirculation in patients with increased risk for cardiovascular diseases: A double-blinded placebo-controlled study

Laser Doppler velocimetry estimates tissue perfusion providing a record of microvascular blood flow. Patients with heart disease or diabetes mellitus have impaired microvascular perfusion leading to impaired wound healing. Aged garlic extract (AGE) has a positive effect on vascular elasticity. This study aimed to assess the effect of long-term treatment with AGE on cutaneous tissue perfusion. A total of 122 patients with Framingham Risk Score ≥ 10 were randomised in a double-blinded manner to placebo or 2400 mg AGE daily for 1 year and monitored. Cutaneous microcirculation was measured at 0 and 12 months using laser Doppler velocimetry. A repeated measures analysis of variance (ANOVA) with a Greenhouse-Geisser correction determined that mean post-occlusive reactive hyperaemia differed significantly between time points. The mean percent change between the two time points 0 and 12 months was 102, 64 (174, 15)% change for AGE and 78, 62 (107, 92)% change for the placebo group (F[1, 120] = 5. 95, P < 0.016), 12 months of AGE increases the microcirculation in patients with an increased risk for cardiovascular events estimated using the Framingham risk score. Increased microcirculation could hypothetically facilitate wound healing.

EWMA Document: Negative Pressure Wound Therapy

1. Introduction Since its introduction in clinical practice in the early 1990's negative pressure wounds therapy (NPWT) has become widely used in the management of complex wounds in both inpatient and outpatient care.¹ NPWT has been described as a effective treatment for wounds of many different aetiologies^2,3 and suggested as a gold standard for treatment of wounds such as open abdominal wounds,^4-6 dehisced sternal wounds following cardiac surgery^7,8 and as a valuable agent in complex non-healing wounds.^9,10 Increasingly, NPWT is being applied in the primary and home-care setting, where it is described as having the potential to improve the efficacy of wound management and help reduce the reliance on hospital-based care.¹¹ While the potential of NPWT is promising and the clinical use of the treatment is widespread, highlevel evidence of its effectiveness and economic benefits remain sparse.^12-14 The ongoing controversy regarding high-level evidence in wound care in general is well known. There is a consensus that clinical practice should be evidence-based, which can be difficult to achieve due to confusion about the value of the various approaches to wound management; however, we have to rely on the best available evidence. The need to review wound strategies and treatments in order to reduce the burden of care in an efficient way is urgent. If patients at risk of delayed wound healing are identified earlier and aggressive interventions are taken before the wound deteriorates and complications occur, both patient morbidity and health-care costs can be significantly reduced. There is further a fundamental confusion over the best way to evaluate the effectiveness of interventions in this complex patient population. This is illustrated by reviews of the value of various treatment strategies for non-healing wounds, which have highlighted methodological inconsistencies in primary research. This situation is confounded by differences in the advice given by regulatory and reimbursement bodies in various countries regarding both study design and the ways in which results are interpreted. In response to this confusion, the European Wound Management Association (EWMA) has been publishing a number of interdisciplinary documents^15-19 with the intention of highlighting: The nature and extent of the problem for wound management: from the clinical perspective as well as that of care givers and the patients Evidence-based practice as an integration of clinical expertise with the best available clinical evidence from systematic research The nature and extent of the problem for wound management: from the policy maker and healthcare system perspectives The controversy regarding the value of various approaches to wound management and care is illustrated by the case of NPWT, synonymous with topical negative pressure or vacuum therapy and cited as branded VAC (vacuum-assisted closure) therapy. This is a mode of therapy used to encourage wound healing. It is used as a primary treatment of chronic wounds, in complex acute wounds and as an adjunct for temporary closure and wound bed preparation preceding surgical procedures such as skin grafts and flap surgery. Aim An increasing number of papers on the effect of NPWT are being published. However, due to the low evidence level the treatment remains controversial from the policy maker and health-care system's points of view-particularly with regard to evidence-based medicine. In response EWMA has established an interdisciplinary working group to describe the present knowledge with regard to NPWT and provide overview of its implications for organisation of care, documentation, communication, patient safety, and health economic aspects. These goals will be achieved by the following: Present the rational and scientific support for each delivered statement Uncover controversies and issues related to the use of NPWT in wound management Implications of implementing NPWT as a treatment strategy in the health-care system Provide information and offer perspectives of NPWT from the viewpoints of health-care staff, policy makers, politicians, industry, patients and hospital administrators who are indirectly or directly involved in wound management.

Vacuum-Assisted Wound Closure with Mesh-Mediated Fascial Traction Achieves Better Outcomes than Vacuum-Assisted Wound Closure Alone: A Comparative Study

Background

Open abdomen (OA) permits the application of damage control surgery principles when abdominal trauma, sepsis, severe acute peritonitis and abdominal compartmental syndrome (ACS) occur.

Methods

Non-traumatic patients treated with OA between January 2010 and December 2015 were identified in a prospective database, and the data collected were retrospectively reviewed. Patients’ records were collected from charts and the surgical and intensive care unit (ICU) registries. The Acosta “modified” technique was used to achieve fascial closure in vacuum-assisted wound closure and mesh-mediated fascial traction (VAWCM) patients. Sex, age, simplified acute physiology score II (SAPS II), abdominal compartmental syndrome (ACS), cardiovascular disease (CVD) and surgical technique performed were evaluated in a multivariate analysis for mortality and fascial closure prediction.

Results

Ninety-six patients with a median age of 69 (40–78) years were included in the study. Sixty-nine patients (72%) underwent VAWCM. Forty-one patients (68%) achieved primary fascia closure: two patients (5%) were treated with VAWC (37 median days) versus 39 patients (95%) who were treated with VAWCM (10 median days) (p = 0.0003). Forty-eight patients underwent OA treatment due to ACS, and 24 patients (50%) survived compared to 36 patients (75%) from the “other reasons” group (p = 0.01). The ACS group required longer mechanical ventilator support (p = 0.006), length of stay in hospital (p = 0.005) and in ICU (p = 0.04) and had higher SAPS II scores (p = 0.0002).

Conclusions

The survival rate was 62%. ACS (p = 0.01), SAPS II (p = 0.004), sex (p = 0.01), pre-existing CVD (p = 0.0007) and surgical technique (VAWC vs VAWCM) (p = 0.0009) were determined to be predictors of mortality. Primary fascial closure was obtained in 68% of cases. VAWCM was found to grant higher survival and primary fascial closure rate.

Pressure Distribution during Negative Pressure Wound Therapy of Experimental Abdominal Compartment Syndrome in a Porcine Model

(1) Introduction: Negative pressure wound therapy (NPWT) is a frequently applied open abdomen (OA) treatment. There are only a few experimental data supporting this method and describing the optimal settings and pressure distribution in the abdominal cavity during this procedure. The aim of our study was to evaluate pressure values at different points in the abdominal cavity during NPWT in experimental abdominal compartment syndrome (ACS) animal model; (2) Methods: In this study (permission Nr. 13/2014/UDCAW), 27 Hungahib pigs (15.4-20.2 kg) were operated on. ACS was generated by implanting a plastic bag in the abdomen through mini-laparotomy and filled with 2100-3300 mL saline solution (37 °C) to an intraabdominal pressure (IAP) of 30 mmHg. After 3 h, NPWT (Vivano Med^® Abdominal Kit, Paul Hartmann AG, Germany) or a Bogota bag was applied. The NPWT group was divided into -50, -100 and -150 mmHg suction groups. Pressure distribution to the abdominal cavity was monitored at 6 different points of the abdomen via a multichannel pressure monitoring system; (3) Results: The absolute pressure levels were significantly higher above than below the protective layer. The values of the pressure were similar in the midline and laterally. Amongst the bowels, the pressure values changed periodically between 0 and -12 mmHg which might be caused by peristaltic movements; (4) Conclusions: The porcine model of the present study seems to be well applicable for investigating ACS and NPWT. It was possible to provide valuable information for clinicians. The pressure was well distributed by the protective layer to the lateral parts of the abdomen and this phenomenon did not change considerably during the therapy.

Negative pressure wound therapy: Regulating blood flow perfusion and microvessel maturation through microvascular pericytes

Negative pressure wound therapy (NPWT) has been demonstrated to accelerate wound healing by promoting angiogenesis. However, whether blood flow perfusion is regulated by microvessel maturation and pericytes following NPWT remains unclear, as well as the exact association between pericytes and collagen type IV. The aim of this study was to investigate the relevant association between blood flow perfusion and microvessel maturation and pericytes following NPWT, and to further explore the underlying molecular mechanisms. We also aimed to investigate the association between pericytes and collagen type IV. For this purpose, we created a rat model of diabetic wounds and microvascular blood flow perfusion was detected using a laser Doppler blood perfusion imager. The expression levels of angiogenin-1, tyrosine phosphorylation of tyrosine kinase receptor-2 (Tie-2), α-smooth muscle actin (α-SMA) and collagen type IV were detected and analyzed through immunohistochemistry, immunofluorescence, RT-qPCR and western blot analysis. The results revealed that NPWT promoted the overexpression of angiogenin-1, Tie-2, α-SMA and collagen type IV, and significantly increased blood flow perfusion coupled with microvessel maturation in the NPWT group at the later stages (7–10 days) of wound healing. Our results suggested that NPWT can preferentially enhance vessel maturation and increase the number of pericytes, thus regulating blood flow perfusion. On the other hand, pericytes and collagen type IV had a mutual interaction, promoting microvessel maturation.

Negative pressure therapy versus passive open abdominal drainage for the treatment of septic peritonitis in dogs: A randomized, prospective study

OBJECTIVE

To compare passive open abdominal drainage (POAD) and negative-pressure abdominal drainage (NPAD) using the ABThera™ system in the treatment of septic peritonitis.

STUDY DESIGN

Randomized prospective clinical trial.

ANIMALS

Dogs (n = 16) with septic peritonitis.

METHODS

Dogs with septic peritonitis were randomly assigned to one of two treatment protocols: NPAD versus POAD. Anesthesia time, operating time, duration of drainage, costs, survival, and complications were compared between techniques. Hematological and biochemical parameters in blood and abdominal fluid, and histopathological findings of omentum and abdominal wall tissue samples were compared between NPAD and POAD at time of initial surgery and at time of closure.

RESULTS

Overall survival was 81%. Treatment costs, anesthesia and operating time, drainage time, survival, and postoperative complications were similar between techniques. Loss of total plasma protein and decreased inflammation-related factors in abdominal fluid at time of closure were noted in all patients. Neutrophilic inflammation was greater in abdominal wall samples after NPAD. POAD patients showed discomfort during bandage changes and had frequent leakage of abdominal fluid outside of the bandage.

CONCLUSION

NPAD is an effective alternative to POAD for treatment of septic peritonitis, based on costs and survival. NPAD resulted in less abdominal fluid leakage, and evidence of superior healing on histological evaluation of abdominal tissues.

Classification, prevention and management of entero-atmospheric fistula: a state-of-the-art review

BACKGROUND

Entero-atmospheric fistula (EAF) is an enteric fistula occurring in the setting of an open abdomen, thus creating a communication between the GI tract and the external atmosphere. Management and nursing of patients suffering EAF carries several challenges, and prevention of EAF should be the first and best treatment option.

PURPOSE

Here, we present a novel modified classification of EAF and review the current state of the art in its prevention and management including nutritional issues and feeding strategies. We also provide an overview on surgical management principles, highlighting several surgical techniques for dealing with EAF that have been reported in the literature throughout the years.

CONCLUSIONS

The treatment strategy for EAF should be multidisciplinary and multifaceted. Surgical treatment is most often multistep and should be tailored to the single patient, based on the type and characteristics of the EAF, following its correct identification and classification. The specific experience of surgeons and nursing staff in the management of EAF could be enhanced, applying distinct simulation-based ex vivo training models.

The open abdomen, indications, management and definitive closure

The indications for Open Abdomen (OA) are generally all those situations in which is ongoing the development an intra-abdominal hypertension condition (IAH), in order to prevent the development of abdominal compartmental syndrome (ACS). In fact all those involved in care of a critically ill patient should in the first instance think how to prevent IAH and ACS. In case of ACS goal directed therapy to achieve early opening and early closure is the key: paradigm of closure shifts to combination of therapies including negative pressure wound therapy and dynamic closure, in order to reduce complications and avoid incisional hernia. There have been huge studies and progress in survival of critically ill trauma and septic surgical patients: this in part has been through the great work of pioneers, scientific societies and their guidelines; however future studies and continued innovation are needed to better understand optimal treatment strategies and to define more clearly the indications, because OA by itself is still a morbid procedure.