Outline the principles of, and strategies for management of a persisting broncho-pleural fistula (BPF) in a mechanically ventilated patient.
Include in your answer the advantages and disadvantages of each strategy.
Principles of Management:
1. Drainage
Adequate drainage of the fistula with an intercostal catheter of adequate size to manage a large air leak.
May require multiple catheters, and ability to manage large flow rates.
Minimise suction.
2. Ventilatory management
Aim is to reduce mean airway pressure to reduce flow through fistula tract.
Low tidal volume and PEEP.
Low mandatory breath rate.
Permissive hypercapnoea.
Short inspiratory time.
Attempt to wean to spontaneous breathing mode from mandatory ventilation as soon as practicable and preferably from ventilatory support altogether.
3. General measures
Standard ICU supportive management
Broad spectrum antibiotic cover
Attention to nutritional requirements – patients usually catabolic.
Strategies for Managing Large Leaks:
1. Independent Lung Ventilation
Advantages: - May minimise leak in injured lung whilst preserving gas exchange with conventional parameters in normal lung.
Disadvantages: -requires some form of double lumen tube – difficult to place and secure.
May not be tolerated in hypoxic patients.
Requirement for two ventilators –either synchronous or asynchronous – technically demanding and complex.
2. High Frequency Ventilation
Advantages are that it may reduce peak air pressures and theoretically reduce air leak.
Disadvantages - not widely available. Recent evidence suggesting an increase in mortality for this ventilatory technique in ARDS patients.
3. Surgery
Advantages – Definitive management strategy. May be only option to seal leak.
Disadvantages – Patient may not be fit enough to tolerate.
4. Endobronchial Occlusion
Advantages – Widely available, can be definitive treatment.
Disadvantages – may be technically challenging, not feasible with multiple leaks.
5. Application of PEEP to intercostal catheter
Advantages – may decrease leak volume and maintain intra-thoracic PEEP.
Disadvantages – compromise drainage, risk of tension, not feasible with multiple tubes.
6. ECMO
Advantages – may be only option to treat hypoxia.
Disadvantages – not widely available, complex, little experience.
Examiners' comments: Overall, candidates had poor knowledge of this topic.
This answer would benefit from a tabulated format:
Strategy | Advantages | Disadvantages |
Drainage - large-bore drain - or, multiple drains - minimise suction |
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Ventilator strategy: - low VT - low PEEP - low resp rate - short insp. time - tolerate high PCO2 - wean rapidly - extubate early |
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Independent lung ventilation - dual-lumen tube - or, bronch blocker |
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Surgical repair |
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Bronchial stenting |
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Bronchial occlusion |
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Application of PEEP to the ICC |
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HFOV |
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ECMO |
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