Elsevier

Medicina Intensiva

Volume 40, Issue 4, May 2016, Pages 238-245
Medicina Intensiva

Original
Evolution over a 15-year period of the clinical characteristics and outcomes of critically ill patients with severe community-acquired pneumoniaEvolución durante un período de 15 años de las características clínicas y resultados de los pacientes críticamente enfermos con neumonía comunitaria grave

https://doi.org/10.1016/j.medin.2015.07.005Get rights and content

Abstract

Objectives

To study the characteristics and outcomes of patients in the ICU with severe community-acquired pneumonia (SCAP) over a 15-year surveillance period.

Methods

We conducted a retrospective cohort study of episodes of SCAP, and assessed the epidemiology, etiology, treatment and outcomes of patients admitted to the ICU, comparing three periods (1999–2003, 2004–2008 and 2009–2013).

Results

A total of 458 patients were diagnosed with SCAP. The overall cumulative incidence was 37.4 episodes/1000 admissions, with a progressive increase over the three periods (P < 0.001). Patients fulfilling the two major IDSA/ATS criteria at admission increased from 64.2% in the first period to 82.5% in the last period (P = 0.005). Streptococcus pneumoniae was the prevalent pathogen. The incidence of bacteremia was 23.1%, and a progressive significant reduction in overall incidence was observed over the three periods (P = 0.02). Globally, 91% of the patients received appropriate empiric antibiotic treatment, increasing from 78.3% in the first period to 97.7% in the last period (P < 0.001). Combination antibiotic therapy (betalactam + macrolide or fluoroquinolone) increased significantly from the first period (61%) to the last period (81.3%) (P < 0.001). Global ICU mortality was 25.1%, and decreased over the three periods (P = 0.001).

Conclusions

Despite a progressively higher incidence and severity of SCAP in our ICU, crude ICU mortality decreased by 18%. The increased use of combined antibiotic therapy and the decreasing rates of bacteremia were associated to improved patient prognosis.

Resumen

Objetivos

Estudiar las características y el pronóstico de los pacientes con neumonía grave adquirida en la comunidad ingresados en una unidad de cuidados intensivos (UCI) durante un período de 15 años.

Material y métodos

Estudio retrospectivo de una cohorte de pacientes con neumonía grave comunitaria en los que se analizó la evolución en la epidemiología, etiología, tratamiento y pronóstico durante un período de 15 años, comparando 3 períodos (1999-2003, 2004-2008 y 2009-2013).

Resultados

Un total de 458 pacientes fueron diagnosticados de neumonía. La incidencia media global durante el período estudiado fue de 37,4 episodios/1.000 ingresos, encontrándose un incremento progresivo durante los 3 períodos estudiados (p < 0,001). Los pacientes que cumplían con los 2 criterios mayores de neumonía grave de la ATS/IDSA aumentaron de un 64,2% en el primer período a un 82,5% en el último período (p = 0,005). Streptococcus pneumoniae fue el microorganismo más frecuente aislado. La incidencia de bacteriemia fue del 23,1%, encontrándose una reducción significativa y progresiva en la incidencia a lo largo de los 3 períodos (p = 0,02). El 91% de los pacientes recibió tratamiento antibiótico empírico apropiado, encontrándose un incremento entre el primer y el último período del 78,3% al 97,7% (p < 0,001). El tratamiento combinado (betalactámico + macrólido o quinolona) aumentó de un 61% en el primer período a un 81,3% en el último (p < 0,001). La mortalidad en la unidad de cuidados intensivos durante todo el período fue del 25,1%, encontrándose una disminución progresiva durante los 3 períodos (p = 0,001).

Conclusiones

A pesar de un incremento progresivo en la incidencia y gravedad de las neumonías ingresadas en unidad de cuidados intensivos, la mortalidad se redujo en un 18%. El incremento en la utilización de tratamiento combinado y la disminución en la incidencia de bacteriemia se asociaron a una mejoría en el pronóstico.

Introduction

In the United States, community-acquired pneumonia (CAP) affects >5 million adults and accounts for >1 million hospital admissions each year due to the severity of the disease or decompensation of underlying comorbid disease.1, 2 Severe CAP (SCAP) requiring critical care affects 10–22% of these.3, 4 Morbidity and mortality in patients remain high, despite advances in critical care management and antimicrobial therapy. Mortality in those admitted in to the intensive care unit (ICU), ranges from 21% to 58%.5, 6, 7

Early empiric antimicrobial therapy has proven the most effective approach to decreasing mortality in patients with SCAP. Various organizations, most notably the Infectious Diseases Society of America (IDSA)/American Thoracic Society (ATS)8 and the British Thoracic Society (BTS)9 have published guidelines for managing CAP. Adherence to guidelines has resulted in significant benefits for patients with CAP. In addition, other strategies such as lung protective-ventilation strategy10 and Surviving Sepsis Campaign11 recommendations introduced in recent years have improved outcomes in patients with severe sepsis admitted in the ICU.

We hypothesized that mortality in patients admitted to the ICU with SCAP has decreased even after implementation a higher organ support demand. In the current study we aimed to analyze changes in the epidemiology of SCAP in a large ICU population during 15-years’ surveillance and to determine the evolution of mortality rate and the factors associated with outcome.

Section snippets

Study population

We conducted a retrospective cohort study of episodes of SCAP admitted to the ICU at university hospital in Spain (between January 1, 1999 and December 31, 2013).

Data abstraction

The following information was recorded using standardized methods: sex, age, alcohol use, comorbidities, initially prescribed antibiotic regimen, microbiological findings, and etiologic diagnosis. Intubation and mechanical ventilation requirements, systemic response and patient outcome were also recorded. Patients were observed until

Incidence

In the 15-year period, 458 patients were admitted to the ICU for SCAP. The cumulative incidence of patients with SCAP admitted to the ICU over the whole study period was 37.4 episodes/1000 admissions, and the incidence progressively increased over the 3 periods, from 29.8 episodes/1000 admissions in the first period, to 48.9 episodes/1000 admissions in the third period (P < 0.001).

Patient characteristics

Table 1 reports the clinical characteristics of patients with SCAP admitted to the ICU in the three periods. On

Discussion

This study provides a comprehensive picture of the clinical and microbiologic epidemiology of SCAP over 15-year periods in a large ICU population. The main findings were the progressively higher incidence of SCAP in patients admitted to ICU and the 18% reduction in crude ICU mortality.

Although the definition of SCAP remains somewhat subjective and imprecise, in practice, SCAP is often defined by respiratory and/or circulatory failure requiring admission to the ICU.13 The IDSA/ATS Joint

Conflict of interest

The authors do not have potential conflicts of interest with any companies/organizations whose products or services may be discussed in this article.

References (31)

  • M.J. Fine et al.

    Prognosis and outcomes of patients with community-acquired pneumonia: a meta-analysis

    J Am Med Assoc

    (1996)
  • L.A. Mandell et al.

    Infectious Disease Society of America/American Thoracic Society consensus guidelines on the management of community-acquired pneumonia in adults

    Clin Infect Dis

    (2007)
  • W.S. Lim et al.

    BTS guidelines for the management of community-acquired pneumonia in adults: update 2009

    Thorax

    (2009)
  • The Acute Respiratory Distress Syndrome Network

    Ventilation with lower tidal volumes as compared with traditional tidal volumes for acute lung injury and the acute respiratory distress syndrome

    N Engl J Med

    (2000)
  • R.P. Dellinger et al.

    Surviving sepsis campaign: international guidelines for management of severe sepsis and septic shock 2012

    Intensive Care Med

    (2013)
  • Cited by (37)

    • Usefulness of β-lactam and macrolide combination therapy for treating community-acquired pneumonia patients hospitalized in the intensive care unit: Propensity score analysis of a prospective cohort study

      2021, Journal of Infection and Chemotherapy
      Citation Excerpt :

      The PS was estimated by multivariate logistic regression analysis involving six covariates: age, sex, C-reactive protein, albumin, PSI score, and APACHE II score. These covariates were selected based on previous reports analysing prognostic factors for CAP patients in the ICU [21–24]. All statistical analyses were two-tailed, and a P value < 0.05 was considered significant.

    • Updates on community acquired pneumonia management in the ICU

      2021, Pharmacology and Therapeutics
      Citation Excerpt :

      Although antibiotic-resistant variants of S. pneumoniae, have become increasingly common, the ICU mortality related with pneumococcal pneumonia has decreased over the last decade (Gattarello et al., 2014). In a study from Spain of SCAP patients spanning 3 time periods from 1999 - 2013, S. pneumoniae was the most common pathogen isolated with an overall incidence of 41.7% and over 80% of all causes of bacteremia (Valles et al., 2016). Other pathogens implicated with severe CAP include viruses (e.g., influenza, avian-origin influenza A - H7N9, novel H1N1, H3N2 influenza, respiratory syncytial virus, coronavirus illness of severe acute respiratory syndrome [SARS], Middle East respiratory syndrome coronavirus (MERS-CoV), atypical bacteria including L. pneumophila, M. pneumoniae, M. tuberculosis, and H. influenzae.

    • Ventilatory Support Use in Hospitalized Patients With Community-Acquired Pneumonia. Fifteen-year Trends in Spain (2001–2015)

      2020, Archivos de Bronconeumologia
      Citation Excerpt :

      Lastly, after adjusting for possible confounders, IHM decreased significantly from 2001 to 2015 in Spain in patients with CAP who received NIV, IMV and NIV + IMV. Vallés et al. also found a decrease in ICU mortality in Spain when they studied the characteristics and outcomes of patients with severe CAP over a 15-year surveillance period (1999–2013), despite a progressively higher incidence and severity of this disease in their ICU.37 In any case, it is possible that changes in hospital protocols, national guidelines or ventilatory strategies over time may have contributed to a reduction in the IHM.

    • Trends in the incidence and mortality of patients with community-acquired septic shock 2003–2016

      2019, Journal of Critical Care
      Citation Excerpt :

      Interestingly, during the study period, mortality among patients who did not require SC decreased from 56.3% in 2003 to 20% in 2016 (p = 0.02), even though they significantly had more comorbidities; by contrast, mortality among patients requiring SC did not decrease significantly (21.4% in 2003 to 27.6% in 2016; p = 0.43), suggesting that, when required, SC is the most important determinant of pathogen clearance and is therefore the main factor in improving prognosis, whereas patients who do not require SC benefit more from improvements in support treatments, such as, protective ventilation, the application of the recommendations of the sepsis guidelines, to the early diagnosis and treatment of patients with septic shock (resuscitation with fluids and early antibiotic treatment) together with a shorter delay in admission to the ICU. More than half of the cases in the group that did not require SC were septic shock secondary to pneumonia and therefore these results would confirm those recently published by our group on the progressive improvement in mortality of patients with severe community-acquired pneumonia [28]. Among comorbidities, only alcoholism and cirrhosis were independently associated with ICU mortality.

    View all citing articles on Scopus
    View full text