Incidences of Pseudomonas associated Ventilator-associated pneumonia within studies of respiratory tract applications of polymyxin: testing the Stoutenbeek concurrency postulates. [PublishAheadOfPrint]

Regimens containing topical polymyxin appear highly effective at preventing Ventilator-associated pneumonia (VAP) overall and more-so, gram negative VAP. However, Soutenbeek's postulates, that VAP incidences within studies of topical antibiotics would depend on the context of whether the component (control and intervention) groups of each study were concurrent versus non-concurrent, remain untested.

The literature was searched for concurrent control (CC) versus non-concurrent control (NCC) designed studies of respiratory tract applications of topical polymyxin to mechanically ventilated (MV) patients that reported Pseudomonas associated Ventilator-associated pneumonia (PsVAP) incidences. Studies of various interventions other than topical polymyxin (non-polymyxin studies) served to provide additional points of reference. The PsVAP incidences within the component groups of all studies were benchmarked against groups from observational studies. This was undertaken by meta-regression using generalized estimating equation methods. Dot plots, caterpillar plots and funnel plots enable visual benchmarking.

The PsVAP benchmark (and 95 % confidence interval) derived from 102 observational groups is 4.6 % (4.0-5.3 %). By contrast, the mean PsVAP within NCC polymyxin intervention groups (1.6 %; 1.0 – 4.5 %) is lower than all other component group categories. The mean PsVAP within CC polymyxin control groups (9.9 %; 7.6 – 12.8 %) is higher than all other component group categories.

The PsVAP incidences of control and intervention groups of studies of respiratory tract applications of polymyxin is dependent on whether the groups were within a concurrent versus non-concurrent study. Soutenbeek's concurrency postulates are validated.

https://ift.tt/2x0d4z7