Hospital-acquired pneumonia

Last reviewed: 28 Aug 2022
Last updated: 18 Nov 2021



History and exam

Key diagnostic factors

  • dyspnea
  • productive cough
  • fever
More key diagnostic factors

Other diagnostic factors

  • chest pain
  • asymmetric expansion of the chest
  • diminished resonance
  • egophony
  • whisper pectoriloquy
  • crackles or rhonchi
  • tachycardia
  • malaise/anorexia
Other diagnostic factors

Risk factors

  • poor infection control/hand hygiene
  • head of bed at <30° angle
  • intubation and mechanical ventilation; endotracheal cuff pressure <20 cm H2O
  • H2 antagonist and antacid use
  • poor oral hygiene
  • no interruption in sedation
  • reintubation
More risk factors

Diagnostic investigations

1st investigations to order

  • chest x-ray
  • WBC count with differential
  • pulse oximetry
  • culture of lower respiratory tract sample
More 1st investigations to order

Investigations to consider

  • ABG
  • diagnostic thoracentesis
  • CT chest
  • CRP
  • procalcitonin
More investigations to consider

Treatment algorithm


before culture results: without risk factors for multidrug-resistant (MDR) pathogen

before culture results: with risk factors for multidrug-resistant (MDR) pathogen, including Pseudomonas and MRSA


after culture results: due to gram-negative pathogen

after culture results: due to gram-positive pathogen



Forest W. Arnold, DO, MSc, FIDSA
Forest W. Arnold

Associate Professor of Medicine

Division of Infectious Diseases

Department of Medicine

School of Medicine

University of Louisville




FWA declares that he has no competing interests.

Peer reviewers

Krishna Sundar, MD, FCCP

Associate Professor (Clinical)

Department of Medicine

University of Utah


Pulmonary and Critical Care Research

IHC Urban South

Utah Valley Pulmonary Clinic



KS declares that he has no competing interests.

Ozan Akca, MD

Director of Research

Associate Professor

Department of Anesthesiology and Perioperative Medicine

Neuroscience and Anesthesia Intensive Care Unit

University of Louisville




OA declares that he has no competing interests.

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