Discrepancies in Control Group Mortality Rates Within Studies Assessing Topical Antibiotic Strategies to Prevent Ventilator-Associated Pneumonia: An Umbrella Review

Overview

Journal Crit Care Explor

Specialty Critical Care

Date 2020 Mar 14

PMID 32166296

Citations 7

Authors

James C Hurley

Affiliations

Soon will be listed here.

Abstract

Objectives: To test the postulate that concurrent control patients within ICUs studying topical oropharyngeal antibiotics to prevent ventilator-associated pneumonia and mortality would experience spillover effects from the intervention.

Data Sources: Studies cited in 15 systematic reviews of various topical antibiotic and other infection prevention interventions among ICU patients.

Study Selection: Studies of topical antibiotics, stratified into concurrent control versus nonconcurrent control designs. Studies of nondecontamination-based infection prevention interventions provide additional points of reference. Studies with no infection prevention intervention provide the mortality benchmark. Data from additional studies and data reported as intention to treat were used within sensitivity tests.

Data Extraction: Mortality incidence proportion data, mortality census, study characteristics, group mean age, ICU type, and study publication year.

Data Synthesis: Two-hundred six studies were included. The summary effect sizes for ventilator-associated pneumonia and mortality prevention derived in the 15 systematic reviews were replicated. The mean ICU mortality incidence for concurrent control groups of topical antibiotic studies (28.5%; 95% CI, 25.0-32.3; = 41) is higher versus the benchmark (23.7%; 19.2-28.5%; = 34), versus nonconcurrent control groups (23.5%; 19.3-28.3; = 14), and versus intervention groups (24.4%; 22.1-26.9; = 62) of topical antibiotic studies. In meta-regression models adjusted for group-level characteristics such as group mean age and publication year, concurrent control group membership within a topical antibiotic study remains associated with higher mortality ( = 0.027), whereas other group memberships, including membership within an antiseptic study, are each neutral ( = not significant).

Conclusions: Within topical antibiotic studies, the concurrent control group mortality incidence proportions are inexplicably high, whereas the intervention group mortality proportions are paradoxically similar to a literature-derived benchmark. The unexplained ventilator-associated pneumonia and mortality excess in the concurrent control groups implicates spillover effects within studies of topical antibiotics. The apparent ventilator-associated pneumonia and mortality prevention effects require cautious interpretation.

Citing Articles

Structural Equation Modelling as a Proof-of-Concept Tool for Mediation Mechanisms Between Topical Antibiotic Prophylaxis and Six Types of Blood Stream Infection Among ICU Patients.

Hurley J Antibiotics (Basel). 2024; 13(11).

PMID: 39596789 PMC: 11591272. DOI: 10.3390/antibiotics13111096.

Indirect (herd) effects of topical antibiotic prophylaxis and oral care versus non-antimicrobial methods increase mortality among ICU patients: realigning Cochrane review data to emulate a three-tier cluster randomised trial.

Hurley J BMJ Open. 2023; 13(11):e064256.

PMID: 38035749 PMC: 10689355. DOI: 10.1136/bmjopen-2022-064256.

Trends in ICU mortality and underlying risk over three decades among mechanically ventilated patients. A group level analysis of cohorts from infection prevention studies.

Hurley J Ann Intensive Care. 2023; 13(1):62.

PMID: 37432605 PMC: 10335996. DOI: 10.1186/s13613-023-01159-0.

Establishing the safety of selective digestive decontamination within the ICU population: a bridge too far?.

Hurley J Trials. 2023; 24(1):337.

PMID: 37198636 PMC: 10189709. DOI: 10.1186/s13063-023-07356-3.

Selective digestive decontamination, a seemingly effective regimen with individual benefit or a flawed concept with population harm?.

Hurley J Crit Care. 2021; 25(1):323.

PMID: 34470654 PMC: 8408564. DOI: 10.1186/s13054-021-03744-w.

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