Aspiration pneumonia Clindamycin (600 mg IV every 8 hours) or ampicillin·sulbactam (3 g IV every 12 hours)

or moxifloxacin ( 400 mg IV daily)

HAP, HCAP, or neutropenia Antipseudomonal beta·lactam (eg, Zosyn 4.5 g IV every 6 hours}, an anti·MRSA antibiotic (vancomycin

15 mg/kg IV every 12 hours) and a fluoroquinolone (levofloxacin 750 mg IV every 8 hours)

H IV/AIDS suspected of PCP pneumonia Add trimethoprim/sulfamethoxazole (5 mg/kg of the trimethoprim component IV every 8 hours)

and prednisone 40 mg PO 30 minutes before antibiotics when the p02 is <70 mmHg

AI DS, acqui red immune deficiency syndrome; CAP, commun ity-acquired pneumon ia; HAP, hospita l-acquired pneumon ia; HCAP, health

care-acquired pneumonia; HIV, human immu nodeficiency vi rus; MRSA, methicillin -resista nt Staphylococcus oureus; PO, per os (by mouth);

PCP, Pneumocystis corinii pneumonia.

should be performed early in the ED visit (preferably from

triage) and continue when the patient is admitted.

...... Droplet Precautions

Droplets are particles >5 microns that travel in the air but

only remain floating for a very limited time. Transmission

occurs usually within 3 feet of the patient. Common

pathogens transmitted by the droplet route include respiratory viruses (eg, influenza, parainfluenza, and adenovirus), Bordetella pertussis, Neisseria meningitides (in the first

24 hours of treatment), Mycoplasma pneumoniae, rubella,

and severe acute respiratory syndrome (SARS).

In addition to standard precautions, healthcare workers should wear a mask when working within 6 feet of the

patient. Respirator masks and air handling systems are

not necessary. The door to the patient's room doesn't

have to be closed (as transmission is limited to 3 feet), but

doing so can help remind health care workers they are

entering a room with droplet precautions. If a single

patient room is not available, the patient should be more

than 3 feet away from other patients and a curtain drawn

between them.

...... Airborne Precautions

Airborne droplets are <5 microns and can remain suspended in the air for extended periods of time. Human to

human transmission usually occurs via inhalation. The most

common pathogen transmitted via the airborne route is TB.

Other common pathogens include measles, varicella (until

lesions are crusted over), disseminated herpes, and SARS

(though predominantly transmitted via droplet).

Health care workers should place patients in airborne

infection isolation rooms (AIIR). These are negative pressure rooms with a minimum of 6-12 air changes per hour

and a door that can be closed. When entering the room,

health care workers need to wear respirator masks for

which the efficacy of the seal formed is evaluated. These

N-95 respirator masks remove 95% of droplets. Once the

patient vacates the room, the room will need to be open for

1 hour for enough air exchanges to occur to remove any

offending organism.

DISPOSITION

...... Admission

There are several clinical guidelines (Pneumonia Severity

Index or CURB-65) to help risk-stratify patients and aid in

the disposition. These guidelines consider risk factors associated with increased morbidity and mortality. Risk factors

include elderly or nursing home residents, the presence of

com or bid disease (congestive heart failure, cancer, liver

disease, stroke, chronic renal disease), altered mental status, respiratory rate >30 breaths/min, systolic blood pressure <90 mmHg, temperature <35°C (95°F) or >40°C

(104°F), pulse >125 bpm, pH <7.35, blood urea nitrogen

>30 mg/dL, Na <130 mEq/L, glucose >250 mg/dL, hematocrit <30%, arterial p02 <60 mmHg, and pleural effusion .

Although these risk factors and clinical guidelines should

be considered in deciding to admit a patient, other factors

such as the social situation, ability to follow-up, and other

medical conditions may also play a role in the decision to

admit the patient. Consider infection control measures, as

outlined previously, on all admitted patients.

...... Discharge

Patients without a complicated course or risk factors and

who have a good social situation may be discharged home

with appropriate follow-up.

CHAPTER 23

SUGGESTED READING

Emerman CL, Anderson E, Cline DM. Community-acquired

pneumonia, aspiration pneumonia, and noninfectious pulmonary infiltrates. In: Tintinalli JE, Stapczynski JS, Ma OJ,

Cline DM, Cydulka RK, Meckler GD. Tintinalli's Emergency

Medicine: A Comprehensive Study Guide. 7th ed. New York,

NY: McGraw-Hill, 20 1 1, pp. 479-49 1.

Mandell, LA, Wunderink, RG, Anzueto A, et a!. Infectious Diseases

Society of America/American Thoracic Society Consensus

guidelines on the management of community-acquired pneu ­