TY - CHAP M1 - Book, Section TI - Pneumonia A1 - Wunderink, Richard G. A1 - Waterer, Grant A2 - Hall, Jesse B. A2 - Schmidt, Gregory A. A2 - Kress, John P. PY - 2015 T2 - Principles of Critical Care, 4e AB - Pneumonia is one of the most common causes of ICU admission, usually because of impending respiratory failure or hemodynamic compromise.Pneumonia on admission to the intensive care unit presents in three different forms: traditional community-acquired pneumonia (CAP), hospital-acquired pneumonia (HAP), and the controversial entity of health care–associated pneumonia (HCAP).By far, the most important risk factor for oropharyngeal colonization with pathogenic bacteria is the use of antibiotics; the broader the antibiotic spectrum and the longer the duration of treatment, the more likely that pathogenic bacteria will colonize the oropharynx.Despite concern about secretion clearance, intermittent noninvasive ventilation (NIV) with careful attention to increasing secretion clearance has a survival benefit in CAP and immunocompromised patients with pulmonary infiltrates.CAP is the leading cause of infectious death around the world and a frequent cause of ICU admission.While Streptococcus pneumoniae remains the most common cause of severe CAP, other pathogens are overrepresented in patients admitted to the ICU, including Staphylococcus aureus, Legionella, Pseudomonas, and other gram negatives.Because of the broader spectrum of etiologies, an aggressive diagnostic approach is appropriate in patients admitted to the ICU with CAP. Blood cultures and tracheal aspirate/bronchoalveolar lavage samples through the endotracheal tube are much more likely to be positive than in non-ICU patients.Patients initially admitted to a non-ICU setting but subsequently requiring ICU transfer have high mortality that exceeds that of patients with equivalent illness at presentation who are admitted directly to the ICU. Presence of at least three of a set of minor criteria for severity identifies patients likely needing ICU care and the probability increases with an increasing number of these minor criteria.The HCAP designation was developed in response to the consistent finding of pneumonia acquired while outside the hospital but caused by pathogens traditionally associated with HAP, such as MRSA, Pseudomonas, and drug-resistant Enterobacteriaceae. The definition remains very controversial.HAP precipitating respiratory failure and ICU transfer is now more common than VAP complicating respiratory failure, although both are caused by similar multidrug-resistant (MDR) pathogens.At least one potential pathogen is isolated in up to 75% of patients with HAP who are intubated. Access to the lower respiratory tract via the endotracheal tube is the most important reason for the higher diagnostic yield.Broad-spectrum β-lactam antibiotics are the backbone of treatment for HAP and HCAP, but emerging antibiotic resistance patterns make choice of specific agents—piperacillin/tazobactam, late generation cephalosporins, or carbapenems—difficult. The use of combination therapy and the routine need for MRSA coverage remain controversial.De-escalation of antibiotic therapy once the results of cultures are known is critical for management of ventilated ICU patients with HCAP and HAP. SN - PB - McGraw-Hill Education CY - New York, NY Y2 - 2024/03/28 UR - accesssurgery.mhmedical.com/content.aspx?aid=1107720147 ER -