Empirical antimicrobial therapy for probable v. directed therapy for possible ventilator-associated pneumonia in critically injured patients

Abstract

Background. Ventilator-associated pneumonia (VAP) has recently been classified as possible or probable. Although direct attributable mortality has been difficult to prove, delay in instituting appropriate therapy has been reported to increase morbidity and mortality. Recent literature suggests that in possible VAP, instituting directed therapy while awaiting microbiological culture does not prejudice outcome compared with best-guess empirical therapy. Objectives. To ascertain outcomes of directed v. empirical therapy in possible and probable VAP, respectively. Methods. Endotracheal aspirates were obtained from patients with suspected VAP. Those considered to have possible VAP were given directed therapy following culture results, whereas patients with more convincing evidence of VAP were classed as having probable VAP and commenced on empirical antimicrobials based on microbiological surveillance. Results. Pneumonia was suspected in 106 (36.8%) of 288 patients admitted during January -December 2014. Of these, 13 did not fulfil the criteria for VAP. Of the remaining 93 (32.2%), 31 (33.3%) were considered to have probable and 62 (66.7%) possible VAP. The former were commenced on empirical antimicrobials, with 28 (90.3%) receiving appropriate therapy. Of those with possible VAP, 34 (54.8%) were given directed therapy and in 28 (45.2%) no antimicrobials were prescribed. Of the latter, 24 recovered without antimicrobials and 4 died, 3 from severe traumatic brain injury and 1 due to overwhelming intra-abdominal sepsis. No death was directly attributable to failure to treat VAP. No significant difference in mortality was found between the 34 patients with possible VAP who were commenced on directed therapy and the 31 with probable VAP who were commenced on empirical antimicrobials (p=0.75). Conclusions. Delaying antimicrobial therapy for VAP where clinical doubt exists does not adversely affect outcome. Furthermore, this policy limits the use of antimicrobials in patients with possible VAP following improvement in their clinical condition despite no therapy.

A review of the complications encountered in a quaternary trauma intensive care unit in South Africa

“…25 Antimicrobials may not be necessary, and due to its inherent multi-drug resistance our policy is not to institute treatment if found with other pathogens. 26 In the presence of sepsis and if Acinetobacter baumannii is the sole isolate, then therapy is commenced as it may be pathogenic. 27 If regarded as colonization, the incidence of sepsis-related complications may have been overestimated in this study.…”

The effect of prior antimicrobial therapy for community acquired infections on the aetiology of early and late onset ventilator-associated pneumonia in a level I trauma intensive care unit

“…data confirm that this distinction remains useful when deciding upon empiric therapy. 11 In our study it was observed that community acquired flora susceptible to amoxycillin/clavulanate accounted for the vast majority of pathogens isolated in early VAP. Suggestions that the distinction between early and late VAP should be abandoned emanate from the developed world where widespread antimicrobial use has led to a high level of bacterial resistance within the community.…”

“…Although the isolated flora may be similar in intensive care units the extent and specifics of bacterial resistance to antimicrobials varies considerably, the most common reasons are prior antimicrobial exposure, the overuse of broad spectrum agents and selective pressure. 11 Despite suggestions that the differentiation between early and late VAP is irrelevant and that all patients should be treated with broad spectrum agents, 16 our Funding -No funding has been received.…”

Prevalence of Clinical Signs Within Reference Ranges Among Hospitalized Patients Prescribed Antibiotics for Pneumonia

“…[32][33][34] Quality improvement initiatives in which clinicians empirically prescribed antibiotic therapy only for patients with signs of possible sepsis but waited for confirmatory data before prescribing for those without sepsis suggest that this strategy is not only safe but may even confer a mortality benefit. [35][36][37][38] Similarly ranges. [21][22][23] Integrating serial procalcitonin monitoring may further facilitate this strategy.…”