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The initial treatment for aspiration pneumonia greatly depends on its early diagnosis and includes treatment of acute hypoxemia and bronchospasm. The patient would most certainly need to be hospitalized. Nasogastric tube feeding would be discontinued and suctioning of the upper airway would be carried out to eliminate all traces of foreign material or secretions still present in the oropharynx. Suctioning should be performed carefully to avoid inducing gagging.
While the initial assessments are being made, supplementary oxygen by a mask or nasal cannula may be administered. A ‘venturi mask’ ensuring a consistent, high concentration oxygen is recommended.In severe cases, intubation and mechanical ventilator support may be required. Aspiration causes almost immediate lung injury and bronchoscopy can only help to remove particles or foreign body accidentally inhaled.
Most episodes of nosocomial pneumonia do not need antibiotic therapy. Prophylactic antibiotic treatment may not prevent subsequent infectious pneumonia and is therefore not recommended. However doctors often prefer starting the treatment with broad spectrum antibiotics as many patients who aspirate are either debilitated or immunocompromised and are at greater risk of developing infectious pneumonia.
In most cases, patients suffering from aspirated pneumonia are initially treated empirically. The patient risk factors, coverage of pathogens, the intensity of the infection and expert opinion will determine the course of antibiotic regimen. Only a few controlled clinical trials that compare treatment regimens for aspiration have been performed. A rational approach based on local pathogens, the physician’s knowledge of the medical history of the patient, and anti microbial resistance patterns works better than the use of a particular regimen or course of treatment. Adjunctive corticosteroids may actually be toxic and have therefore no proven value in the treatment of aspiration pneumonia.
The antibiotic regimens recommended for community acquired aspiration pneumonia are clindamycin (Cleocin), beta-lactam and beta-lactamase inhibitor combinations such as ampicillin sodium and sulbactam sodium (Unasyn), or penicillin plus metronidazole (Flagyl). Despite being effective in vitro activity against most anaerobes, monotherapy with metronidazole has been associated with a high clinical failure rate and should not be used to treat aspiration pneumonia. The newer fluoroquinolones], gatifloxacin [Tequin], (eg, levofloxacin [Levaquin } and moxifloxacin hydrochloride [Avelox]) have reasonable anaerobic activity and achieve high concentrations in lung tissue and endobronchial secretions. Aaztreonam (Azactam), and aminoglycosides and trimethoprim-sulfamethoxazole (Bactrim, Cotrim, Septra)have little or no activity against anaerobes.
In case of nosocomial aspiration pneumonia, antimicrobial coverage for gram-negative bacilli and staphylococci must be considered. For patients in intensive care units and for those in whom pneumonia develops after a hospitalization of 5 or more days, the risk of aggressive pathogens such as Pseudomonas aeruginosa and Acinetobacter species, is highest. Patients with head trauma, coma, end stage renal disease, diabetes mellitus and those diagnosed to be colonized by S aureus are at high risk for staphylococcal pneumonia.
For patients with hospital acquired pneumonia, the recommended course of treatment could be ceftazidime plus clindamycin or metronidazole cefepime hydrochloride (Maxipime) or; a beta-lactamase and beta-lactam inhibitor combination such as sulbactam ampicillin and ticarcillin and clavulanate potassium (Timentin) , piperacillin sodium and tazobactam sodium (Zosyn); or a newer fluoroquinolone. For those patients allergic to penicillin, the phycisian may consider either a combination of clindamycin plus aztreonam or may recommend a newer fluoroquinolone. For patients diagnosed with nasopharyngeal colonization with staphylococci and for patients with other staphylococcal infections, an antistaphylococcal coverage may be recommended. Also, a sample of sputum gram stain would be reviewed for the presence gram-positive cocci in clusters. In hospitals where methicillin resistant S aureus is a concern, vancomycin (Vancocin, Vancoled) should be used initially for antistaphylococcal coverage. The American Thoracic Society has prescribed procedures on treatment of hospital- acquired pneumonia in adults which would prove as a useful tool for phycisians to select appropriate initial antibiotic regimens.
Once the physician decides to begin with an antibiotic course of treatment, the patient’s progress would be closely monitored. If the response over the next 1 to 2 days shows rapid clearing of pulmonary infiltrates, then this indicates chemical pneumonitis rather than bacterial pneumonia and hence antibiotic therapy should be stopped immediately. A review of culture resulta after 2 to 3 days could be used to narrow antimicrobial coverage.
In one study conducted, the evaluation of fever in patients diagnosed with aspiration pneumonia was similar to that in patients with pneumococcal pneumonia. In about one half of the patients with aspiration pneumonia, defervescence occurred within 2 days after being started on antibiotic therapy and 80% became afebrile within 5 days. Fever tends to be prolonged in patients with lung abscess or with infections caused by aggressive pathogens such as P aeruginosa.
The duration of antiobiotic therapy for aspiration pneumonia has not been determined by any specific studies undertaken. A treatment lasting between 5 to 7 days appears to be sufficient for patients who respond promptly. In case highly resistant pathogens such as acinetobacter species or P aeruginosa are isolated, the treatment would be extended up to to 14 to 21 days. A long term treatment of 4 to 8 weeks or more amy be needed for patients with cavitary pneumonia or lung abscess.
Some complications of aspiration pneumonia include empyema, lung abscess and bronchopleural fistula. Most lung abscesses respond well to prolonged antibiotic treatment. In patients with empyema, adequate pleural drainage is required.
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