Should routine surgical wound drainage after ventral hernia repair be avoided? A systematic review and meta-analysis

AIMS

To evaluate outcomes of drain use vs. no-drain use during ventral hernia repair.

METHODS

A PRISMA-compliant systematic review was conducted using the following databases: PubMed, Scopus, Cochrane database, The Virtual Health Library, Clinical trials.gov and Science Direct. Studies comparing use of drains with no-drain during ventral hernia repair (primary or incisional) were included. Wound-related complications, operative time, need for mesh removal and early recurrence were the evaluated outcome parameters.

RESULTS

Eight studies reporting a total number of two thousand four hundred and sixty-eight patients (drain group = 1214; no-drain group = 1254) were included. The drain group had a significantly higher rate of surgical site infections (SSI) and longer operative time compared with the no-drain group [odds ratio (OR): 1.63, P = 0.01] and [mean difference (MD): 57.30, P = 0.007], respectively. Overall wound-related complications [OR: 0.95, P = 0.88], seroma formation [OR: 0.66, P = 0.24], haematoma occurrence [OR: 0.78, P = 0.61], mesh removal [OR: 1.32, P = 0.74] and early hernia recurrence [OR: 1.10, P = 0.94] did not differ significantly between the two groups.

CONCLUSION

The available evidence does not seem to support the routine use of surgical drains during primary or incisional ventral hernia repairs. They are associated with increased rates of SSIs and longer total operative time with no significant advantage in terms of wound-related complications.

Quantum phase transitions in the Kondo-necklace model: perturbative continuous unitary transformation approach

The Kondo-necklace model can describe magnetic low-energy limit of strongly correlated heavy fermion materials. There exist multiple energy scales in this model corresponding to each phase of the system. Here, we study quantum phase transition between the Kondo-singlet phase and the antiferromagnetic long-range ordered phase, and show the effect of anisotropies in terms of quantum information properties and vanishing energy gap. We employ the 'perturbative continuous unitary transformations' approach to calculate the energy gap and spin-spin correlations for the model in the thermodynamic limit of one, two, and three spatial dimensions as well as for spin ladders. In particular, we show that the method, although being perturbative, can predict the expected quantum critical point, where the gap of low-energy spectrum vanishes, which is in good agreement with results of other numerical and Green's function analyses. In addition, we employ concurrence, a bipartite entanglement measure, to study the criticality of the model. Absence of singularities in the derivative of concurrence in two and three dimensions in the Kondo-necklace model shows that this model features multipartite entanglement. We also discuss crossover from the one-dimensional to the two-dimensional model via the ladder structure.

Anti-oxidant effect of flavonoids on hemoglobin glycosylation

A high glucose concentration has been found to lead to the glycosylation of amino groups of lysine residue in proteins. The addition of reducing agent not only prevents this reaction but also reverses it. On the other hand, flavonoids which found in plant sources have antioxidant properties. Since the glycosylation of protein is an oxidation reaction, therefore, antioxidants should be able to prevent this reaction. In this study, the best concentration and time to incubate glucose with hemoglobin was investigated. Then the glycosylation degree of hemoglobin in the presence of flavonoids and their absence was measured by means of a colorimetric method. Different concentration of flavonoids (Quercetin, Rutin, Kaempferol) were used. The preventing effect on hemoglobin glycosylation by the three concentrations; 0.5, 5, 10 micrograms/ml was estimated as follows: for Rutin; 11%, 27%, 42%, Quercetin; 3%, 37%, 52%, Kaempferol; 10%, 12%, 15% respectively. So, the in vivo effect should be investigated and then plants that containing flavonoids can be utilized to prevent or treat complication of diabetes.