Should vacuum-assisted closure therapy be routinely used for ...

ARTICLE IN PRESS doi:10.1510/icvts.2007.157370

Interactive CardioVascular and Thoracic Surgery 6 (2007) 523–528 www.icvts.org

Best evidence topic - Cardiac general

Should vacuum-assisted closure therapy be routinely used for management of deep sternal wound infection after cardiac surgery? Shahzad G. Raja*, Geoffrey A. Berg Department of Cardiothoracic Surgery (Level 9), Western Infirmary Glasgow, Dumbarton Road, Glasgow, G11 6NT, UK Received 4 April 2007; accepted 5 April 2007

Summary A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was whether vacuumassisted closure (VAC) should be routinely used for management of deep sternal wound infection after cardiac surgery. Altogether, 198 papers were identified using the reported search. A further three relevant papers were identified by hand searching reference lists. Thirteen papers represented the best evidence on the topic. The author, journal, date and country of publication, patient group studied, study type, relevant outcomes, results and study weaknesses were tabulated. We conclude that VAC provides a viable and efficacious adjunctive method by which to treat postoperative wound infection after cardiac surgery. It is especially useful for managing sternal osteomyelitis in high-risk patients and is an attractive option as a first-line therapy in this group of patients. However, currently the evidence to endorse its routine use for management of deep sternal wound infection after cardiac surgery is weak. A randomised controlled trial comparing VAC therapy with the conventional treatment is mandatory to validate its safety, efficacy, and cost effectiveness as a routine first-line therapy for management of deep sternal wound infection after cardiac surgery. 䊚 2007 Published by European Association for Cardio-Thoracic Surgery. All rights reserved. Keywords: Vacuum-assisted closure therapy; Deep sternal wound infection; Cardiac surgery; Evidence-based medicine

1. Introduction A best evidence topic was constructed according to the structured protocol. This protocol is fully described in the ICVTS w1x. 2. Clinical scenario You are asked to see a patient with deep sternal wound infection following coronary artery bypass surgery. You feel that a wound debridement with closure will probably be the best approach. However, your consultant wants this patient’s wound to be managed with vacuum-assisted closure (VAC) therapy. You manage the patient as desired by the consultant but decide to review the literature to see if there is any evidence to back up this strategy. 3. Three-part question Should wvacuum-assisted closure therapyx be routinely used for management of wdeep sternal wound infectionx after wcardiac surgeryx? 4. Search strategy Medline 1966 to November 2006 using OVID interface, EMBASE 1980 to 2006 Week 52. *Corresponding author. Tel.: q44 141 211 2000; fax: q44 141 211 1751. E-mail address: [email protected] (S.G. Raja). 䊚 2007 Published by European Association for Cardio-Thoracic Surgery

wexp Vacuum-assisted closure therapy OR VAC.mp.yx AND wexp Deep sternal wound infection OR Postoperative wound infection OR mediastinitis OR poststernotomy mediastinitisyx AND wexp Cardiopulmonary Bypass OR CABG.mp. OR exp Thoracic Surgery OR exp Cardiac surgical procedures OR Coronary art$ bypass.mp. OR Cardiopulmonary bypass. mp. OR exp Cardiovascular Surgical ProceduresyOR exp Thoracic Surgical ProceduresyOR exp Coronary Artery BypassyOR cardiac transplantation.mp. OR exp Heart Transplantationyx. 5. Search outcome A total of 198 papers were identified using the reported search. A further three relevant papers were identified by hand searching reference lists. Thirteen papers w3–15x represented the best evidence on the subject and are summarised in Table 1. 6. Results Poststernotomy mediastinitis, also commonly called deep sternal wound infection, is one of the most feared complications in patients undergoing cardiac surgery. The overall incidence of poststernotomy mediastinitis is relatively low, between 1% and 3%, however, this complication is associated with a significant mortality, usually reported to vary between 10% and 25% w2x. The conventional treatment for poststernotomy mediastinitis usually involves surgical revision, closed irrigation, or reconstruction with omentum or

ARTICLE IN PRESS S.G. Raja, G.A. Berg / Interactive CardioVascular and Thoracic Surgery 6 (2007) 523–528

524 Table 1 Summary of best evidence papers Author, Date, Journal and Country of publication, study (Level of evidence)

Patient group

Outcome

Key results

Commentsy Weaknesses

Cowan et al. (2005), Ann Thorac Surg, Canada, w3x

22 patients treated with VAC for post-cardiac surgery wound complications

Morbidity and mortality

Vacuum-assisted closure induced granulation of 71% of the sternal wound area by 7 days, with a daily drainage of approximately 84 ml. By 14 days, there was a 54% reduction in wound size, and patients were discharged after approximately 19.5 days and placed on home therapy. Vacuumassisted closure was discontinued at approximately 36.7 days with an average reduction in sternal wound size of 80%. Extensive secondary surgical closure, requiring muscle flaps, was avoided in 64% of patients, whereas 28% of patients required no surgical reconstruction for wound closure. No complications were related to VAC use

Small sample size. No control group. Retrospective chart review



VAC was utilized for an average period of 11 days per patient. Sixty-eight percent of the patients (70 of 103) had definitive chest closure with open reduction internal fixation andyor flap closure. The remaining 32% had no definitive closure method. The overall mortality rate was 28% (29 of 103 patients), although no deaths were directly related to use of the therapy, and only four deaths resulted from sepsis as a consequence of mediastinitis

Largest series to date. Sixty-four percent of the patients had a diagnosis of mediastinitis; 36% had either superficial infections or a sterile wound. No control group. Retrospective review

46 patients treated with VAC for post-cardiac surgery mediastinitis and 4781 patients who underwent isolated CABG without mediastinitis

Long-term survival

There was no difference in early or late survival between the mediastinitis group treated with vacuum-assisted closure and the control group (Psnot significant). The survival at 1, 3, and 5 years was 92.9%"4.0%, 89.2%"5.2%, and 89.2%"5.2%, respectively, in the vacuum-assisted closure group; and 96.5%"0.3%, 92.1%"0.5%, and 86.9%"0.8%, respectively, in the control group

Small sample size. Retrospective analysis

61 patients treated with VAC for post-cardiac surgery mediastinitis and 40 patients treated with conventional treatment for post-cardiac surgery mediastinitis

Morbidity, mortality and survival

The 90-day mortality was 0% in the vacuumassisted closure group and 15% in the conventional treatment group (P-0.01). The failure rate to first-line treatment with vacuum-assisted closure and conventional treatment were 0% and 37.5%, respectively (P-0.001). There was no statistically significant difference in the recurrence of sternal fistulas after vacuum-assisted closure therapy or conventional treatment: 6.6% vs. 5.0%, respectively. Overall survival in the vacuum-assisted closure group was significantly better (P-0.05) than in the conventional treatment group: 97% vs. 84% (6 months), 93% vs. 82% (1 year), and 83% vs. 59% (5 years)

The cohorts were from different time periods. Non-randomized retrospective analysis

35 patients treated with VAC for post-cardiac surgery wound complications and 33 patients treated with conventional treatment for post-cardiac surgery wound complications

Comparison of time interval from sternal infection until freedom of microbiological cultures, in-hospital stay, the status at discharge

Freedom from mediastinal microbiological cultures was achieved earlier (P-0.01), C-reactive protein levels declined more rapidly (P-0.025), in-hospital stay was shorter (P-0.01), rewiring was earlier (P-0.01), and survival tended to be higher (P-0.15) in the vacuum group compared to the conventional group

Non-randomized retrospective analysis. Mixture of superficial and deep sternal wound infection

Retrospective cohort (Level 3b)

Agarwal et al. (2005), Plas Reconstr Surg, USA, w4x

Retrospective cohort (Level 3b)

Sjogren et al. (2005), Ann Thorac Surg, Sweden, w5x Case-control study (Level 3b)

Sjogren et al. (2005), Ann Thorac Surg, Sweden, w6x Cohort study (Level 3b)

Fuchs et al. (2005), Ann Thorac Surg, Germany, w7x Cohort study (Level 3b)

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Table 1 (Continued) Author, Date, Journal and Country of publication, study (Level of evidence)

Patient group

Outcome

Key results


Scholl et al. (2004), J Card Surg, USA, w8x



Of the 13 patients, the VAC device was used prior to flap closure in six patients, and after flap closure in two patients. Sternal debridement with bilateral pectoralis muscle flaps was used to reconstruct 12 patients, and one patient underwent debridement only with VAC placement. All 13 patients (100%) had complete closure of their complex wounds at an average of follow-up of 14 months

Small sample size. Retrospective case series

40 patients treated with VAC for post-cardiac surgery deep sternal wound infection


No deaths during the 90 days of follow-up. Three late deaths unrelated to the infection and three subcutaneous fistulas occurred during the total follow-up period (3–41 months). The median duration of the vacuum-assisted closure therapy was 10 days (range, 3–34). The series represents a total of 474 days with the vacuum-assisted closure device without serious adverse events

Retrospective series

102 patients treated with VAC for post-cardiac surgery wound complications Ninety-six of the 102 patients received vacuumassisted therapy while the remaining six underwent daily multiple dressing changes without vacuumassisted therapy


Fifty-three of the 96 patients required only sternal debridement, followed by wound vacuum therapy and closure by secondary intention, while the remaining 43 had an additional procedure. Of these, 33 patients underwent omental transposition and ten patients had a pectoralis flap. The length of stay for all patients was 27"12 days. This was related in part to intravenous antibiotics. Hospital mortality for all patients was 3.7% (four patients)

Large case series. Retrospective analysis

27 patients treated with VAC for post-cardiac surgery wound complications Group A (ns14) had vacuumassisted closure as the final treatment modality, whereas in group B (ns13) vacuum-assisted closure was followed by either a myocutaneous flap (ns8) or primary (ns5) wound closure


In group A, four patients died and a satisfactorily healed scar was achieved in 64% of cases. Median durations of vacuum-assisted closure and hospital stay in group A were 13.5 days (interquartile range 8.8–32.2 days) and 20 days (interquartile range 16.7–25.2 days), respectively. Mortality was 7.7% in group B, with a treatment failure rate of 15%. Median duration of vacuum-assisted closure in group B was 8 days (interquartile range 5.5–18 days), and median hospital stay was 29 days (interquartile range 25.8–38.2 days). During the year before institution of vacuum-assisted closure, poststernotomy infection (ns13) was managed with rewiring and closed irrigation system. Treatment during this year failed in 30.7% of cases (ns4y13), and mortality was also 30.7%. The total cost (hospitalization and treatment) per patient for vacuum-assisted closure was 16,400 dollars, compared with 20,000 dollars for the closed irrigation system treatment

Retrospective analysis. Small sample size

17 patients treated with VAC alone for post-cardiac surgery wound complications and 18 patients treated with traditional twice-a-day

Comparison of number of days between initial debridement and closure, number of dressing changes, number and types of flaps needed for

The V.A.C. therapy group had a trend toward a shorter interval between debridement and closure, with a mean of 6.2 days, whereas the dressing change group had mean of 8.5 days. The V.A.C. therapy group had a significantly lower number of dressing changes, with a mean of three, whereas the twice-a-day dressing change group had a mean of 17 (P-0.05). Reconstruction required an average


Retrospective case series (Level 4)

Gustafsson et al. (2003), Ann Thorac Surg, Sweden, w9x Retrospective cohort study (Level 3b) Domkowski et al. (2003), J Thorac CardioVasc Surg, USA, w10x Retrospective cohort study (Level 3b)

Luckraz et al. (2003), J Thorac CardioVasc Surg, UK, w11x Small cohort study (Level 3b)

Song et al. (2003), Plast Reconstr Surg, USA, w12x Small cohort study (Level 3b)

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526 Table 1 (Continued) Author, Date, Journal and Country of publication, study (Level of evidence)

Doss et al. (2002), Eur J Cardiac Surg, Germany, w13x Small cohort study (Level 3b)

Gustafsson et al. (2002), J Thorac CardioVasc Surg, Sweden, w14x Small cohort study (Level 3b)

Hersh et al. (2001), Ann Plast Surg, USA, w15x Small cohort study (Level 3b)

Patient group

Outcome

Key results

dressing changes

reconstruction, and complications

of 1.5 soft-tissue flaps per patient treated with traditional dressing changes versus 0.9 soft-tissue flaps per patient for those treated with V.A.C. therapy (P-0.05). Before closure, there was one death among patients undergoing dressing changes and three in the V.A.C. therapy group, all of which were unrelated to the management of the sternal wound. Patients with sternal wounds who have benefited from V.A.C. therapy alone had a significant decrease in the number of dressing changes and number of soft-tissue flaps needed for closure. The V.A.C. therapy group had a trend towards a decreased number of days between debridement and closure

22 patients treated with VAC alone for post-sternotomy osteomyelitis and 22 patients treated by conventional wound management


The patients treated by VASD had a significantly reduced treatment duration (mean 17.2"5.8 vs. 22.9"10.8 days, Ps0.009) and total hospital stay (mean 27.2"6.5 vs. 33.0"11.0 days, Ps0.03). Perioperative mortality was similar, with one early death in each group


16 patients treated with VAC for post-sternotomy deep sternal wound infection followed by direct surgical closure


All patients were alive and free from deep sternal wound infection three months after the operation. The median vacuum-assisted closure treatment time until surgical closure was 9 days (range, 3–34 days), and the median C-reactive protein level at closure was 45 mgyl (range, 20–173 mgyl). The median hospital stay was 22 days (range, 12–120 days)


16 patients treated with VAC for post-sternotomy deep sternal wound infection after initial wound debridement


Fifteen of the 16 patients survived and went on to complete wound healing and discharge from the hospital (average length of stay, 16.7 days). One patient sustained a cardiac dysrhythmia during the muscle flap procedure and died. There were no complications related directly to the use of the V.A.C.


pectoral muscle flaps. Recently, VAC therapy has emerged as a novel strategy for management of poststernotomy mediastinitis. The Lund University Hospital group have published several series suggesting that vacuum-assisted closure therapy is a safe and reliable option in poststernotomy mediastinitis with excellent short as well as long-term survival and a very low failure rate compared with conventional treatment w5, 6x. According to this group, reconstruction of the sternum can be achieved in all patients without the use of muscle or omental flap surgery w9, 14x. Agarwal et al. w4x reported similar success rates for VAC as the first-line therapy in the management of sternal wounds. This is the largest retrospective series to date reporting VAC use in 103 patients. An earlier series by the same group w12x also showed that VAC therapy alone leads to a significant decrease in the number of dressing changes and number of soft-tissue flaps needed for closure. In addition, patients treated with VAC therapy had a trend towards a decreased


number of days between debridement and closure. Domkowski et al. w10x in their retrospective analysis of 102 patients also found VAC as an effective therapy for mediastinitis following debridement or before placement of a vascularized tissue flap. Similar conclusion was drawn by Cowan et al. w3x, Scholl et al. w8x and Hersch et al. w15x. Five studies specifically comparing VAC therapy with conventional therapy have shown that freedom from mediastinal microbiological cultures was achieved earlier, C-reactive protein levels declined more rapidly, in-hospital stay was shorter, rewiring was earlier, and survival tended to be higher in the VAC group compared to the conventional group w6, 7, 11–13x. Currently the evidence to endorse routine use for management of deep sternal wound infection after cardiac surgery is weak. A randomised controlled trial comparing VAC therapy with the conventional treatment involving surgical revision, closed irrigation, or reconstruction with omentum or pectoral muscle flaps is mandatory to validate its safety,


efficacy, and cost effectiveness as a routine first-line therapy for management of deep sternal wound infection after cardiac surgery 7. Clinical bottom line VAC is an effective and safe adjunctive strategy to manage post-cardiac surgery deep sternal wound infection. It is especially useful for managing sternal osteomyelitis in highrisk patients and is an attractive option as a first-line therapy in this group of patients. References w1x Dunning J, Prendergast B, Mackway-Jones K. Towards evidence-based medicine in cardiothoracic surgery: best BETS. Interact CardioVasc Thorac Surg 2003;2:405–409. w2x Sjogren J, Malmsjo M, Gustafsson R, Ingemansson R. Poststernotomy mediastinitis: a review of conventional surgical treatments, vacuumassisted closure therapy and presentation of the Lund University Hospital mediastinitis algorithm. Eur J Cardiothorac Surg 2006 Oct 20; wEpub ahead of printx. w3x Cowan KN, Teague L, Sue SC, Mahoney JL. Vacuum-assisted wound closure of deep sternal infections in high-risk patients after cardiac surgery. Ann Thorac Surg 2005;80:2205–2212. w4x Agarwal JP, Ogilvie M, Wu LC, Lohman RF, Gottlieb LJ, Franczyk M, Song DH. Vacuum-assisted closure for sternal wounds: a first-line therapeutic management approach. Plast Reconstr Surg 2005;116:1035– 1040. w5x Sjogren J, Nilsson J, Gustafsson R, Malmsjo M, Ingemansson R. The impact of vacuum-assisted closure on long-term survival after poststernotomy mediastinitis. Ann Thorac Surg 2005;80:1270–1275. w6x Sjogren J, Gustafsson R, Nilsson J, Malmsjo M, Ingemansson R. Clinical outcome after poststernotomy mediastinitis: vacuum-assisted closure versus conventional treatment. Ann Thorac Surg 2005;79:2049–2055. w7x Fuchs U, Zittermann A, Stuettgen B, Groening A, Minami K, Koerfer R. Clinical outcome of patients with deep sternal wound infection managed by vacuum-assisted closure compared to conventional therapy with open packing: a retrospective analysis. Ann Thorac Surg 2005; 79:526–531. w8x Scholl L, Chang E, Reitz B, Chang J. Sternal osteomyelitis: use of vacuum-assisted closure device as an adjunct to definitive closure with sternectomy and muscle flap reconstruction. J Card Surg 2004;19:453– 461. w9x Gustafsson RI, Sjogren J, Ingemansson R. Deep sternal wound infection: a sternal-sparing technique with vacuum-assisted closure therapy. Ann Thorac Surg 2003;76:2048–2053. w10x Domkowski PW, Smith ML, Gonyon DL Jr, Drye C, Wooten MK, Levin LS, Wolfe WG. Evaluation of vacuum-assisted closure in the treatment of poststernotomy mediastinitis. J Thorac CardioVasc Surg 2003;126:386– 390. w11x Luckraz H, Murphy F, Bryant S, Charman SC, Ritchie AJ. Vacuum-assisted closure as a treatment modality for infections after cardiac surgery. J Thorac CardioVasc Surg 2003;125:301–305. w12x Song DH, Wu LC, Lohman RF, Gottlieb LJ, Franczyk M. Vacuum-assisted closure for the treatment of sternal wounds: the bridge between debridement and definitive closure. Plast Reconstr Surg 2003;111:92– 97. w13x Doss M, Martens S, Wood JP, Wolff JD, Baier C, Moritz A. Vacuumassisted suction drainage versus conventional treatment in the management of poststernotomy osteomyelitis. Eur J Cardiothorac Surg 2002;22: 934–938. w14x Gustafsson R, Johnsson P, Algotsson L, Blomquist S, Ingemansson R. Vacuum-assisted closure therapy guided by C-reactive protein level in patients with deep sternal wound infection. J Thorac CardioVasc Surg 2002;123:895–900. w15x Hersh RE, Jack JM, Dahman MI, Morgan RF, Drake DB. The vacuumassisted closure device as a bridge to sternal wound closure. Ann Plast Surg 2001;46:250–254.

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ICVTS on-line discussion A Title: Multiple modalities for deep sternal wound infection management Author: Chung-Dann Kan, Surgery, Department of Surgery, National Cheng Kung University Hospital, Tainan 70124, Taiwan doi:10.1510/icvts.2007.157370A eComment: Vacuum-assisted closure (VAC) therapy is one of the effective and safe adjunctive modality for managing post-cardiac surgery deep sternal wound infection w1x. However, management of the deep sternal wound should combine with all methods to eradicate the infectious foci and then the curative goal will be achievable. A 54-year-old male patient suffering from aortic root aneurysm with coronary artery disease received Bentall’s operation combined with coronary bypass grafting surgery, all uneventful. However, two months later, when he came back to the out-patient clinic, he was noted with sternal wound infection. Aggressive debridement surgery was arranged. On the operative theatre, synthetic aortic graft bleeding was noted. Deep sternal wound infection with graft invasion was noted, emergent aortic graft replacement was done. One month later, his infectious condition recurred. We re-did Bentall’s operation again to eradicate the prosthetic valve endocarditic foci, closely irrigated the wound with copious beta-iodine solution, and then utilized VAC therapy to hasten the clearance and healing rate of the sternal wound. After all prompt management, this patient received bilateral pectoris major muscle flap reconstruction. From the above described patient, we know the prompt management of the patient should combine all modalities to eradicate the infectious foci and adjunctive therapies to accelerate the wound healing process, only through this can the patient get healthy again. Reference w1x Raja SG, Berg GA. Should vacuum-assisted closure therapy be routinely used for management of deep sternal wound infection after cardiac surgery? Interact CardioVasc Thorac Surg 2007;6:523–528.

ICVTS on-line discussion B Title: VAC therapy in post cardiac surgery deep sternal wound infection Authors: Mohamed F. Ibrahim, PSHC, King Fahd Medical City, Riyadh 11525, Saudi Arabia; Amal A. Refaat doi:10.1510/icvts.2007.157370B eComment: We read with interest the paper by Raja and colleagues w1x that raised the question of whether vacuum-assisted closure (VAC) therapy should be used routinely for the management of deep sternal wound infection following cardiac surgery. I agree with the conclusion of the authors that VAC therapy is especially useful in high-risk patients with sternal osteomyelitis as an attractive first line therapy. We have been using VAC therapy for the management of post cardiac surgery deep sternal wound infection since its introduction in the early 1990’s. In our early experience, we used it as our first and definitive line of management for all deep sternal wound infections. This definitely led to a reduction in our rate of surgical procedures in the form of sternal debridement, closed irrigation, sternal rewiring, and flaps. Our initial experience was similar to that of Lund University Hospital group w2x and the experience of Agarwal et al. w3x. Although there was a significant reduction in the number of dressing changes and the number of tissue flaps and the surgical interventions required. There was a marked increase in the hospital stay required by every patient with consequent increase in the cost of therapy. This has led us to modify our protocol of using VAC therapy. We use it now as an initial management only for high risk patients with associated high surgical risk. VAC therapy leads to: 1. reduction in the number of dressing changes, 2. stabilization of the flail chest caused by the unstable sternum which leads to improvement in gas exchange, 3. reduction of the risk associated with major surgical correction in unstable patients. In case of low risk patients, we tend to go directly with early surgical revision, debridement, rewiring or early flap reconstruction.