Effectiveness of negative pressure closure in the integration of split thickness skin grafts: a randomized, double-masked, controlled trial.

OBJECTIVES: To determine the effectiveness of the negative pressure closure (NPC) technique in the integration of split-thickness skin grafts (STSG) to the recipient site. METHODS: Randomized, double-masked, controlled trial. SETTING: A tertiary burn unit. PATIENT CHARACTERISTICS: Between May 2003 and October 2004, 60 patients having wounds with skin loss which hindered primary closure, were incorporated to this study. We excluded patients with > or =20% of total body surface burns, polytraumatized, surgical contraindications, those who were enlisted in other clinical trials, and those who rejected the informed consent. INTERVENTIONS: In all the patients, surgical cleaning of the recipient site and STSG were performed after which they were randomly assigned between 2 groups: a group that received a NPC dressing and were connected to the central aspiration system at -80 mm Hg versus a control group with similar dressing but without connection to negative pressure. Loss of STSG area at the fourth postoperative day, days of hospital stay. RESULTS: Sixty patients were included. The median loss of the STSG in the NPC group was 0.0 cm versus 4.5 cm in the control group (P = 0.001). The median hospital stay was of 13.5 days in the NPC group versus 17 days in the control group (P < 0.001). CONCLUSIONS: The use of NPC significantly diminishes the loss of STSG area, as well as shortens the days of hospital stay. Therefore, it should be routinely used for these kinds of procedures.

Concordance between qualitative and quantitative cultures in burned patients. Analysis of 2886 cultures.

OBJECTIVE: To determine the concordance between superficial cultures (SC) and quantitative cultures (QC) in the diagnosis of wound infection in burn patients. SAMPLE: All SC and QC taken from the same patient, site and during the same surgery were analysed. VARIABLES: On the SC, the microorganism (MO) and its amount defined subjectively by the microbiologist was recorded (negative, very low, low, regular and abundant). On the QC, the MO and its amount were expressed as colony forming units per gram of tissue (CFUs/g). STATISTICS: Kappa index of agreement beyond chance; Wilcoxon and Kruskall-Wallis for continuous variables and chi(2) for categorical variables were used with a p<0.05 indicating statistical significance. RESULTS: One thousand four hundred and forty three pairs of cultures were analyzed. The concordance between SC and QC (Kappa index) was 52%. On the SC, only when the microbiologist subjectively informed "abundant" MOs there was a significant difference (p<0.0001). There were 6.1% of QCs with more than 10(5) CFUs/g and the most frequent MOs isolated were: S. aureus (27.9%), E. coli (11.6%), P. aeruginosa (11.6%), E. faecalis (11.6%) and S. epidermidis (7.0%). CONCLUSIONS: SC has a moderate concordance with the QC showing a low reliability between the two methods. The subjective information given by the microbiology technician in the SC is not precise. A study in which the two methods be compared blindly against the reference standard, in a prospective cohort of patients, it is needed to discriminate which of two methods it is the most accurate one determining sensitivity and specificity.