Recurrent aspiration

Recurrent aspiration is repeated entry of oropharyngeal secretions, food, liquid or gastric contents into the larynx and lower airway. It causes pneumonitis, pneumonia, lung abscess, empyema, or chronic lung injury, and it often signals an underlying swallowing, neurological or oesophageal disorder.

Clinical relevance. Aspiration is a common cause of pneumonia in older adults, nursing home residents and patients with neurological disease. Recurrence means the cause has not been found or controlled. Aspiration may be silent, with no cough or choking.

Types.

• Aspiration pneumonitis (Mendelson syndrome): chemical injury within minutes to hours from acidic gastric contents. Initially sterile.
• Aspiration pneumonia: bacterial infection by oropharyngeal flora over hours to days.
• Chronic microaspiration: repeated small volumes leading to chronic cough, aspiration bronchiolitis, bronchiectasis or interstitial lung disease.
• Airway obstruction from a food bolus or foreign body.
• Lipoid pneumonia from aspirated oils.

Mechanisms. Impaired oropharyngeal swallow (neurological, muscular, structural), reduced consciousness, impaired cough, gastro-oesophageal reflux, gastric outlet or small bowel obstruction, gastroparesis, enteral feeding, poor oral hygiene and dentition, sedating and anticholinergic drugs.

Distribution. Aspiration in the upright position favours the right lower lobe. In the supine position the posterior segments of the upper lobes and the superior segments of the lower lobes are involved.

Key distinctions. Pneumonitis is chemical and often improves without antibiotics, while pneumonia needs them. Recurrent aspiration also needs to be separated from other causes of recurrent chest infection.

History.

• Coughing or choking with meals or drinks, wet voice, drooling, food avoidance, prolonged meals, weight loss.
• Recurrent chest infections, nocturnal cough, morning sputum.
• Regurgitation, heartburn, vomiting, dysphagia for solids or liquids.
• Neurological disease: stroke, Parkinson disease, motor neurone disease, myasthenia gravis, dementia. Head and neck cancer and radiotherapy. Previous surgery, tracheostomy, enteral feeding.
• Drugs: sedatives, anticholinergics, antipsychotics, opioids. Alcohol, seizures.

Examination.

• Oral hygiene, dentition, saliva pooling, tongue movement and strength, palatal elevation, voice quality (wet or gurgly), volitional cough, neck masses.
• Chest: coarse crackles, bronchial breathing, wheeze, particularly in dependent zones.
• Neurological: bulbar and pseudobulbar signs, fatigable weakness, parkinsonism, fasciculations.
• Nutrition and hydration.

Bedside tests. Water swallow test (coughing, choking or voice change within 1 minute is abnormal), repeated saliva swallow test (fewer than 3 swallows in 30 seconds is abnormal). Gag reflex is a poor predictor and should not be used to clear a patient for oral intake. Bedside tests miss silent aspiration.

Red flags.

• Stridor or respiratory distress.
• Haemoptysis, or progressive dysphagia with weight loss (cancer).
• Fever with sepsis features.
• Hypoxia or respiratory failure.
• Bulbar weakness with respiratory weakness (myasthenic crisis, motor neurone disease, Guillain-Barre syndrome).
• New neurological deficit.

Special groups. Dementia and nursing home residents. Enterally fed patients (check head position, tube position and feed rate). Post-stroke patients (swallow screen on admission).

Oropharyngeal dysphagia.

• Neurological: stroke, Parkinson disease, progressive supranuclear palsy, multiple system atrophy, motor neurone disease, Guillain-Barre syndrome, advanced dementia.
• Neuromuscular: myasthenia gravis, polymyositis, dermatomyositis, inclusion body myositis, oculopharyngeal muscular dystrophy.
• Structural: head and neck cancer and radiotherapy effects, Zenker diverticulum, cricopharyngeal dysfunction, cervical osteophytes, post surgical change.
• Xerostomia, including Sjogren syndrome and drug effects.

Oesophageal and gastric disorders. Achalasia, oesophageal stricture, oesophageal cancer, gastro-oesophageal reflux disease, hiatus hernia, systemic sclerosis, gastroparesis, gastric outlet obstruction, tracheo-oesophageal fistula.

Reduced consciousness and cough. Sedative or alcohol intoxication, seizures, delirium, coma, vocal cord paralysis, tracheostomy cuff problems, nasogastric tube malposition.

Mimics of recurrent chest infection. Bronchiectasis, cystic fibrosis, immunodeficiency, tuberculosis, bronchial obstruction by lung cancer, heart failure, chronic obstructive pulmonary disease, foreign body.

Step 1. Confirm the episode. Chest radiograph for infiltrates in dependent segments, abscess or effusion. CT chest if non-resolving at 2 to 4 weeks, recurrent in the same segment (obstruction), suspected abscess, empyema or bronchiectasis.

Step 2. Assess severity and cause of illness. Oxygen saturation and arterial blood gas in severe illness, full blood count, urea, creatinine, CRP, blood cultures in sepsis, and sputum culture. Procalcitonin has limited value.

Step 3. Define the swallowing problem. Speech and language therapy clinical swallow evaluation, then instrumental assessment with videofluoroscopic swallow study or fibreoptic endoscopic evaluation of swallowing. The Penetration-Aspiration Scale grades 6 to 8 indicate aspiration. Videofluoroscopy exposes the patient to radiation and fibreoptic endoscopy cannot show the airway at the moment of swallow.

Step 4. Search for the cause.

• Oesophagogastroduodenoscopy and barium swallow for stricture, mass, diverticulum or achalasia. High resolution manometry for motility disorders. pH and impedance monitoring for reflux when reflux is suspected as the driver. Gastric emptying study for gastroparesis.
• Laryngoscopy for vocal cord and laryngeal pathology.
• MRI brain and spine, creatine kinase, acetylcholine receptor and muscle specific kinase antibodies, nerve conduction and electromyography for neuromuscular disease.

Limitations. Radiographic changes can lag clinical illness. Silent aspiration is missed without instrumental testing. Culture of sputum reflects oral flora and rarely changes management.

Acute stabilisation. Position upright, suction airway, give oxygen to keep saturation 94 to 98% (88 to 92% when at risk of hypercapnic respiratory failure), and make the patient nil by mouth until swallowing is assessed, with fluids and nutrition given by another route.

Aspiration pneumonitis. Supportive care. Antibiotics are not routine and are started if there is no improvement within 48 hours, a gastric outlet or bowel obstruction, or aspiration of faecal or infected material.

Aspiration pneumonia. Anaerobic cover is not routinely needed, but evidence is limited and many regimens retain it. Cover is added for lung abscess or empyema.

• Amoxicillin with clavulanic acid, oral: 500/125 mg every 8 hours (or 875/125 mg every 12 hours) for 5 to 7 days; dose not to exceed the regimens stated; monitor liver tests with courses over 14 days or liver disease (cholestatic jaundice) and watch for diarrhoea and Clostridioides difficile infection; for eGFR 10 to 30 mL/min use 500/125 mg every 12 hours and avoid the 875 mg tablet, for eGFR under 10 mL/min use 500/125 mg every 24 hours.
• Amoxicillin with clavulanic acid, intravenous: 1.2 g every 8 hours, switched to oral when improving, for 5 to 7 days in total; maximum 3.6 g daily; same monitoring; for CrCl 10 to 30 mL/min give 1.2 g then 600 mg every 12 hours, for CrCl under 10 mL/min give 1.2 g then 600 mg every 24 hours.
• Severe penicillin allergy: moxifloxacin 400 mg orally or IV once daily for 5 to 7 days; maximum 400 mg daily; ECG for QTc, monitor for tendon injury, aortic aneurysm risk, dysglycaemia and C. difficile; avoid with long QT interval, no renal adjustment needed.
• Hospital acquired aspiration or risk of Pseudomonas: piperacillin with tazobactam 4.5 g IV every 6 hours (or every 8 hours in less severe illness) for 5 to 7 days; maximum 18 g piperacillin daily; monitor creatinine and full blood count; reduce to 4.5 g every 8 hours for CrCl 20 to 40 mL/min and 4.5 g every 12 hours for CrCl under 20 mL/min.
• Lung abscess or empyema: prolonged therapy for 4 to 6 weeks or until radiological resolution, with drainage of empyema.

Reduce recurrence.

• Speech and language therapy: swallowing exercises, postural strategies (chin tuck), texture modified diet and thickened fluids when instrumental testing supports it. Thickened fluids reduce aspiration but evidence for fewer pneumonias is limited and dehydration is a risk.
• Upright at 90 degrees for meals and for 30 minutes afterward. Supervised feeding, small mouthfuls, slow pace.
• Oral hygiene: toothbrushing twice daily and dental treatment. Review drugs: reduce sedatives and anticholinergics.
• Reflux: head of bed raised and treat gastro-oesophageal reflux; use omeprazole 20 mg orally once daily for 4 to 8 weeks when reflux is the driver, then review, as acid suppression raises pneumonia risk and should not be given without an indication.
• Enteral feeding: a gastrostomy does not stop aspiration of saliva or reflux. In advanced dementia, tube feeding has not been shown to prolong life or prevent pneumonia, so careful hand feeding is usually preferred. If feeding tubes are used, give continuous feeds with the head raised 30 to 45 degrees and consider post-pyloric placement for gastroparesis.
• Procedural treatment of the cause: dilatation or myotomy for achalasia, diverticulotomy for Zenker diverticulum, cricopharyngeal myotomy for selected patients, management of tracheostomy cuff.
• Goals of care: in advanced disease, discuss comfort feeding and its risks.

Monitoring. Temperature, respiratory rate, saturations and CRP at 48 to 72 hours. Follow-up chest radiograph at 6 weeks for smokers or those over 50 or persisting symptoms. Weight and swallow reassessment.

Referral and escalation. Speech and language therapist for all. Dietitian, respiratory, gastroenterology, ENT, neurology and geriatric medicine depending on the cause. Urgent surgical and respiratory input for empyema or abscess.

Admission criteria. CURB-65 score of 2 or more, hypoxia, sepsis, inability to take oral therapy, unsafe swallow, abscess or empyema, or inability to supervise feeding at home.

Discharge and safety netting. Discharge with a written swallow plan, trained carers, and a review within 1 to 2 weeks. Patients and carers are told to return for fever, breathlessness, new cough after meals, or inability to swallow saliva.