[V.A.C.-treatment: a new approach to the management of septic complications in thoracic surgery]

Intrathoracic negative pressure therapy for pleural empyema using an open-pore drainage film

BACKGROUND

We report our initial experience with intrathoracic negative pressure therapy (ITNPT) in the stage-adjusted treatment of pleural empyema (PE) based on a case series.

MATERIALS AND METHODS

ITNPT represents a further development for intrathoracic use. After thoracic surgical open debridement, an intrathoracic negative pressure dressing was inserted. The drainage elements were a thin open-pore double-layer drainage film (OF) with open-pore polyurethane foams (PUF). Only the OF was placed in direct contact with the lung parenchyma. Negative pressure was generated using an electronic pump (continuous suction, -75 mm Hg). In revision thoracotomies, ITNPT was stopped or continued depending on local findings.

RESULTS

In total, 31 patients with stage II and III pleural empyema underwent ITNPT, which was administered during the primary procedure (n = 17) or at revision (n = 14). Treatment duration was a mean of 10 days (2-18 days) with a mean change interval of 4 days (2-6 days). Intrathoracic negative pressure dressings were applied a mean of 3.5 (1-6) times. The empyema cavity continuously reduced in size and was cleansed by the suction. The OF has a minimum intrinsic volume with maximum absorption surface. Once negative pressure is established, there is no intrathoracic dead volume and the parenchyma can expand. The protective material properties of OF make ITNPT suitable for the treatment of pleural empyema. Targeted local intrathoracic drainage of the septic focus is a possible adjunct to surgery. The surgical dressings must be changed repeatedly. The method is suitable for the treatment of complex stage II and III pleural empyemas.

CONCLUSION

The OF can be used as an intrathoracic drainage element for ITNPT in pleural empyema. This new application option expands the range of indications for negative pressure therapy.

[Intrathoracic negative pressure therapy of pleural empyema using an open-pored drainage film]

INTRODUCTION

We report our initial experience with intrathoracic negative pressure therapy (ITNPT) in the stage-adjusted therapy of pleural empyema (PE) based on a case series.

MATERIALS AND METHODS

ITNPT represents a further development in negative pressure therapy that is designed to be used in the thoracic cavity. After thoracic surgical open debridement, an intrathoracic negative pressure dressing was inserted. The drainage elements used were a thin open-pore double-layer drainage film (OF) with open-pore polyurethane foams (PUF). Only the OF was placed in direct contact with the lung parenchyma. Negative pressure was generated using an electronic pump (continuous suction, -75 mm Hg). In revision thoracotomies, ITNPT was stopped or continued depending on local findings.

RESULTS

31 patients with stage II and III pleural empyemas were treated. ITNPT was administered at the time of primary procedure (n = 17) or revision (n = 14). ITNPT was given over a duration of m = 10 days (2-18 days), change interval m = 4 d (2-6 d). The application of intrathoracic negative pressure dressings was performed m = 3.5 (1-6) times. The empyema cavity continuously reduced in size and was cleansed by the suction. The OF has a minimum intrinsic volume with maximum absorption surface. Once negative pressure is established, there is no intrathoracic dead volume and the parenchyma can expand.

DISCUSSION

The protective material properties of OF make ITNPT suitable for the treatment of pleural empyema. Targeted local intrathoracic drainage of the septic focus is a possible adjunct to surgery. The treatment regimen requires surgical dressings to be changed repeatedly. The method is suitable for the treatment of complex stage II and III pleural empyemas.

CONCLUSION

The OF can be used as an intrathoracic drainage element for ITNPT in pleural empyema. This new application option expands the range of indications for negative pressure therapy.

Complex pleural empyema can be safely treated with vacuum-assisted closure

Objective

For patients with postoperative pleural empyema, open window thoracostomy (OWT) is often necessary to prevent sepsis. Vacuum-assisted closure (VAC) is a well-known therapeutic option in wound treatment. The efficacy and safety of intrathoracal VAC therapy, especially in patients with pleural empyema with bronchial stump insufficiency or remain lung, has not yet been investigated.

Methods

Between October 2009 and July 2010, eight consecutive patients (mean age of 66.1 years) with multimorbidity received an OWT with VAC for the treatment of postoperative or recurrent pleural empyema. Two of them had a bronchial stump insufficiency (BPF).

Results

VAC therapy ensured local control of the empyema and control of sepsis. The continuous suction up to 125 mm Hg cleaned the wound and thoracic cavity and supported the rapid healing. Additionally, installation of a stable vacuum was possible in the two patients with BPF. The smaller bronchus stump fistula closed spontaneously due to the VAC therapy, but the larger remained open.

The direct contact of the VAC sponge did not create any air leak or bleeding from the lung or the mediastinal structures. The VAC therapy allowed a better re-expansion of remaining lung.

One patient died in the late postoperative period (day 47 p.o.) of multiorgan failure. In three cases, VAC therapy was continued in an outpatient service, and in four patients, the OWT was treated with conventional wound care. After a mean time of three months, the chest wall was closed in five of seven cases. However, two patients rejected the closure of the OWT. After a follow-up at 7.7 months, neither recurrent pleural empyema nor BPF was observed.

Conclusion

VAC therapy was effective and safe in the treatment of complicated pleural empyema. The presence of smaller bronchial stump fistula and of residual lung tissue are not a contraindication for VAC therapy.

Bacterial growth kinetic without the influence of the immune system using vacuum-assisted closure dressing with and without negative pressure in an in vitro wound model

The physical capacity of negative pressure wound therapy (NPWT) dressing on the bacterial growth in an in vitro wound model was investigated. Standardised wounds were contaminated with a clinical Staphylococcus aureus strain and incubated at 35 degrees C for 6 hours. Four wounds were treated with continuous negative pressure (125 mmHg) and four controls without. Bacterial load per gram tissue and per gram polyurethane sponge were measured after 24, 36 and 72 hours. Without negative pressure, the initial mean S. aureus load per gram tissue was 1.42 x 10(4), with negative pressure 1.84 x 10(4), P = 0.294. After 24, 36 and 72 hours, both models yielded comparable numbers of organisms (24 hours: P = 0.081; 48 hours: P = 0.455; 72 hours: P = 0.825, respectively). Bacterial load of sponges with or without negative pressure also did not differ. Over a period of 72 hours, sponges with negative pressure yielded 1.60 x 10(8), those without negative pressure yielded 1.74 x 10(8) CFU/g sponge (P = 0.876). In non vital tissue without the influence of the immune system, the bacterial load did not decrease in our in vitro model using an NPWT dressing. This observation was independent of the physical effect of continuous negative pressure at 125 mmHg. The reduction in bacteria demonstrated in previous studies appears to be caused by other effects than physical suction alone. However, the results obtained are limited as non viable tissue was used and the effect of suction on dead tissue might be very different from that occurring on perfused tissue, for example, in an animal model or in patients.