Hospital-acquired pneumonia overview: Difference between revisions
| Line 29: | Line 29: | ||
===History and Symptoms=== | ===History and Symptoms=== | ||
People with pneumonia often have a productive cough, [[fever]][[rigors|shaking chills]], [[shortness of breath]], pleuritic [[chest pain]], [[hemoptysis]], [[headache]]s, [[diaphoresis|sweaty]], and clammy skin. Other possible symptoms are [[anorexia (symptom)|loss of appetite]], fatigue, [[cyanosis]], [[nausea]], [[vomiting]], mood swings, and[[arthralgia|joint pains]] or [[myalgia|muscle aches]]. In elderly people manifestations of pneumonia may not be typical. They may develop a new or worsening confusion or may experience unsteadiness, leading to falls. Infants with pneumonia may have many of the symptoms above, but in many cases they are simply sleepy or have a decreased appetite. In VAP, often no history is available in patients with ventilator-associated pneumonia as they are often sedated and are rarely able to communicate. | People with pneumonia often have a productive cough, [[fever]][[rigors|shaking chills]], [[shortness of breath]], pleuritic [[chest pain]], [[hemoptysis]], [[headache]]s, [[diaphoresis|sweaty]], and clammy skin. Other possible symptoms are [[anorexia (symptom)|loss of appetite]], fatigue, [[cyanosis]], [[nausea]], [[vomiting]], mood swings, and [[arthralgia|joint pains]] or [[myalgia|muscle aches]]. In elderly people manifestations of pneumonia may not be typical. They may develop a new or worsening confusion or may experience unsteadiness, leading to falls. Infants with pneumonia may have many of the symptoms above, but in many cases they are simply sleepy or have a decreased appetite. In VAP, often no history is available in patients with ventilator-associated pneumonia as they are often sedated and are rarely able to communicate. | ||
===Laboratory Findings=== | ===Laboratory Findings=== | ||
Revision as of 19:51, 16 December 2014
|
Hospital-acquired pneumonia Microchapters |
|
Differentiating Hospital-Acquired Pneumonia from other Diseases |
|
Diagnosis |
|
Treatment |
|
Case Studies |
|
Hospital-acquired pneumonia overview On the Web |
|
American Roentgen Ray Society Images of Hospital-acquired pneumonia overview |
|
Directions to Hospitals Treating Hospital-acquired pneumonia |
|
Risk calculators and risk factors for Hospital-acquired pneumonia overview |
Editor(s)-in-Chief: C. Michael Gibson, M.S., M.D. ; Philip Marcus, M.D., M.P.H.
Overview
Hospital-acquired pneumonia (HAP) or nosocomial pneumonia refers to any pneumonia contracted by a patient in a hospital at least 48–72 hours after being admitted. It is thus distinguished from community-acquired pneumonia. It is usually caused by a bacterial infection, rather than a virus.[1][2] HAP is the second most common nosocomial infection (after urinary tract infections ) and accounts for 15–20% of the total.[1][2][3] It is the most common cause of death among nosocomial infections and is the primary cause of death in intensive care units.[1][3] HAP typically lengthens a hospital stay by 1–2 weeks.[1][3]
Pathophysiology
Most nosocomial respiratory infections are caused by so-called skorvatch microaspiration of upper airway secretions, through inapparent aspiration, into the lower respiratory tract. Also, "macroaspirations" of esophageal or gastric material is known to result in HAP. Since it results from aspiration either type is called aspiration pneumonia. Although gram-negative bacilli are a common cause they are rarely found in the respiratory tract of people without pneumonia, which has led to speculation of the mouth and throat as origin of the infection.
Causes
The majority of cases related to various gram-negative bacilli (52%) and S. aureus (19%). Others are Haemophilusspp. (5%). In the ICU results were S. aureus(17.4%), P. aeruginosa (17.4%), Klebsiella pneumoniae andEnterobacter spp. (18.1%), and Haemophilus influenzae (4.9%). Viruses -influenza and respiratory syncytial virus and, in the immunocompromised host, cytomegalovirus- cause 10-20% of infections.
Differentiating Hospital-Acquired Pneumonia From Other Diseases
Hospital-acquired pneumonia must be differentiated from other conditions that cause fever, cough, chest pain, tachycardia, and leukocytosis in hospitalized patients, such as atelectasis, congestive heart failure, pulmonary embolism, aspiration pneumonitis, among others. [4][5]
Epidemiology and Demographics
The epidemiology of health-care-associated pneumonia varies considerably according to the type of health-care setting. Nosocomial pneumonia has been the second most common hospital-associated infection after that of the urinary tract. The primary risk factor for the development of hospital-associated bacterial pneumonia is mechanical ventilation. In long-term care facilities such as nursing homes, pneumonia is the first or second most common infection (after those of the urinary tract) acquired by patients, and accounts for 13-48% of all nursing home-associated infections. [6]
Risk Factors
Among the factors contributing to contracting HAP are mechanical ventilation (ventilator-associated pneumonia), old age, decreased filtration of inspired air, intrinsic respiratory, neurologic, or other disease states that result in respiratory tract obstruction, trauma, (abdominal) surgery, medications, diminished lung volumes, or decreased clearance of secretions may diminish the defenses of the lung. Also poor hand-washing and inadequate disinfection of respiratory devicescauses cross-infection and is an important factor.
Natural History, Complications, and Prognosis
The natural history of HAP depends on many factors and occurs 48 hours or more after hospitalization. Complications include sepsis, respiratory failure, pleural effusion, empyema, and lung abscess. Healthcare-associated pneumonia seems to have fatality rates similar to hospital-acquired pneumonia, worse than community-acquired pneumonia but less severe than pneumonia in ventilated patients. Besides clinical markers like tachypnea (fast breathing) or a high white cell count (leukocytosis), the prognosis seems to be influenced by the underlying associated diseases (comorbidities) and functional capacities.[7][8][9] Many patients have a decreased health condition after the episode.[10]
Diagnosis
Diagnostic Criteria
In hospitalised patient who develop respiratory symptoms and fever one should consider the diagnosis. The likelyhood increases when upon investigation symptoms are found of respiratory insufficiency, purulent secretions, newly developed infiltrate on the chest X-Ray, and increasing leucocyte count. If pneumonia is suspected material from sputum or tracheal aspirates are sent to the microbiology department for cultures. In case ofpleural effusion thoracentesis is performed for examination of pleural fluid. In suspected ventilator-associated pneumonia it has been suggested that bronchoscopy(BAL) is necessary because of the known risks surrounding clinical diagnoses.
History and Symptoms
People with pneumonia often have a productive cough, fevershaking chills, shortness of breath, pleuritic chest pain, hemoptysis, headaches, sweaty, and clammy skin. Other possible symptoms are loss of appetite, fatigue, cyanosis, nausea, vomiting, mood swings, and joint pains or muscle aches. In elderly people manifestations of pneumonia may not be typical. They may develop a new or worsening confusion or may experience unsteadiness, leading to falls. Infants with pneumonia may have many of the symptoms above, but in many cases they are simply sleepy or have a decreased appetite. In VAP, often no history is available in patients with ventilator-associated pneumonia as they are often sedated and are rarely able to communicate.
Laboratory Findings
Current guidelines recommend a combination of chest Xray,laboratory data as well as clinical judgment in diagnosis and management of community acquired pneumonia.
Treatment
Medical Therapy
Methicillin-resistant staphylococcus aureus is a common isolate in the patients with Hospital-acquired pneumonia. The treatment options commonly used are vancomycin, linezolid, and clindamycin. Linezolid may be preferred in patients with renal insufficiency as the nephrotoxicity with Linezolid is less compared to vancomycin. Additionally, in patients with vancomycin MIC ≥ 2mcg/mL linezolid is preferred. Linezolid resistance and failure are rare.
References
- ↑ 1.0 1.1 1.2 1.3 Mandell's Principles and Practices of Infection Diseases 6th Edition (2004) by Gerald L. Mandell MD, MACP, John E. Bennett MD, Raphael Dolin MD, ISBN 0-443-06643-4 · Hardback · 4016 Pages Churchill Livingstone
- ↑ 2.0 2.1 The Oxford Textbook of Medicine Edited by David A. Warrell, Timothy M. Cox and John D. Firth with Edward J. Benz, Fourth Edition (2003), Oxford University Press, ISBN 0-19-262922-0
- ↑ 3.0 3.1 3.2 Harrison's Principles of Internal Medicine 16th Edition, The McGraw-Hill Companies, ISBN 0-07-140235-7
- ↑ Koenig SM, Truwit JD (2006). "Ventilator-associated pneumonia: diagnosis, treatment, and prevention". Clin Microbiol Rev. 19 (4): 637–57. doi:10.1128/CMR.00051-05. PMC 1592694. PMID 17041138.
- ↑ "Guidelines for the Management of Adults with Hospital-acquired, Ventilator-associated, and Healthcare-associated Pneumonia". American Journal of Respiratory and Critical Care Medicine. 171 (4): 388–416. 2005. doi:10.1164/rccm.200405-644ST. ISSN 1073-449X.
- ↑ "CDC GUIDELINES FOR PREVENTING HEALTH-CARE-ASSOCIATED PNEUMONIA, 2003" (PDF).
- ↑ Mehr DR, Zweig SC, Kruse RL; et al. (October 1998). "Mortality from lower respiratory infection in nursing home residents. A pilot prospective community-based study". J Fam Pract. 47 (4): 298–304. PMID 9789516.
- ↑ Mehr DR, Binder EF, Kruse RL; et al. (November 2001). "Predicting mortality in nursing home residents with lower respiratory tract infection: The Missouri LRI Study". JAMA. 286 (19): 2427–36. doi:10.1001/jama.286.19.2427. PMID 11712938.
- ↑ Naughton BJ, Mylotte JM, Tayara A (October 2000). "Outcome of nursing home-acquired pneumonia: derivation and application of a practical model to predict 30 day mortality". J Am Geriatr Soc. 48 (10): 1292–9. PMID 11037018.
- ↑ Fried TR, Gillick MR, Lipsitz LA (March 1997). "Short-term functional outcomes of long-term care residents with pneumonia treated with and without hospital transfer". J Am Geriatr Soc. 45 (3): 302–6. PMID 9063275.