The treatment depends on the cause of acute pericarditis, the person's strength and the presence of pericardial effusion, myocarditis or circulatory failure. In an 1866 answer, rest, relief of pain and repeated assessment of the heart are more defensible starting points than an indiscriminate attempt to suppress every sign of inflammation by depletion.
The bedside assessment would include the history of rheumatic illness, chest pain, a pericardial friction rub, the character of the pulse, breathing, the extent of cardiac dullness on percussion and changes in the heart sounds. Serial examination matters: disappearance of a pericardial friction rub need not mean recovery if fluid is separating the inflamed surfaces. Increasing oppression of breathing, weakness or a failing pulse would require reconsidering both the disease and the treatment. Auscultation with a stethoscope and careful repeated percussion supplied information that modern imaging now refines.
Period practice included local bloodletting with medicinal leeches, counterirritation with a blistering agent, opium for pain and rest, and disputed Mercury treatment intended to alter inflammatory exudation. A robust adult early in an apparently vigorous inflammatory attack was treated differently by depletion advocates from an exhausted person with anaemia, previous blood loss or advanced kidney disease. Even in that framework, a rapid weak pulse was not a command to remove more blood. Nor was Mercury an uncontested standard: a medical address published in December 1866 specifically listed its use in pericarditis among unresolved therapeutic questions.[ref]
Modern correction: establish the diagnosis, identify complications and use cause-directed treatment rather than bloodletting or mercurialization. Electrocardiography, inflammatory markers, troponin where myocardial injury is suspected and echocardiography help distinguish uncomplicated pericarditis from important associated disease. A typical uncomplicated inflammatory episode is treated with aspirin or a suitable nonsteroidal anti-inflammatory drug, usually with colchicine and appropriate gastroprotection. Renal impairment, gastrointestinal bleeding, interactions and a specific infectious or systemic cause can modify this plan. Corticosteroids have selected indications and are not the routine first choice. Activity is restricted during active disease and return to exertion follows reassessment.[ref]
A large pericardial effusion requires attention to its haemodynamic effect, not merely its size. Cardiac tamponade requires urgent specialist drainage and stabilization. Purulent disease requires treatment of the infection and drainage; associated myocarditis or a systemic cause changes management further.[ref] These distinctions explain why treatment cannot be fixed solely by the label “acute”.
Recommend thoracentesis when removing pleural fluid is likely to relieve important respiratory compromise or answer a consequential diagnostic question; the size, course, cause and accessibility of the pleural effusion govern the decision. “Paracentesis thoracis” is the older name. Merely detecting some fluid is insufficient.
At the bedside in 1867, the assessment would combine the history with asymmetry of chest movement, enlargement of the affected side, percussion dullness, diminished breath sounds on auscultation and displacement of the heart. A large or increasing pleural effusion with oppressive dyspnoea, inability to lie comfortably, a displaced heart or failure to improve was a stronger indication than a small resolving collection. The opposite lung's condition also mattered: someone with limited reserve could tolerate compression poorly. These signs have to be interpreted together because extensive lung disease can also produce dullness or abnormal breath sounds.
The distinction between a serous pleural effusion and empyema changes the object of the operation. In the former, the immediate object is decompression and allowing the compressed lung to expand. In empyema, evacuation of infected material is required and continuing drainage may be necessary. Recurrent pleural fluid implies a persisting cause. Conversely, an improving small collection could be watched while treating the associated disease. A period report describes waiting for absorption, then confirming fluid with a grooved needle and evacuating it through a trocar and cannula when the signs and displacement persisted. It illustrates contemporary instruments and reasoning; it is not a safe modern procedural template.[ref]
Modern correction: separate diagnostic aspiration, therapeutic aspiration and drainage of pleural infection. Use imaging to establish the collection and a safe route. A new unexplained unilateral pleural effusion may need sampling even without severe dyspnoea. Pleural fluid testing can include biochemical analysis, cytology and microbiological culture, selected for the suspected cause. With suspected pleural infection, frank pus or sufficiently low pleural fluid pH supports chest drainage rather than repeated simple taps. For example, in the relevant suspected-infection pathway, pH at or below 7.2 signifies high risk and supports drainage if an accessible volume can be drained safely. A typical bilateral collection responding to treatment of heart failure can be approached differently from an unexplained unilateral one.[ref]
Risk assessment includes bleeding risk, ability to cooperate and the availability of an accessible fluid pocket. A very small or inaccessible collection may make aspiration inappropriate. Thoracic ultrasonography is required for pleural effusion aspiration. For therapeutic aspiration, drain slowly with an appropriate catheter; generally do not exceed 1.5 litres in one attempt and stop earlier for chest pain, tightness, persistent cough or worsening dyspnoea. Complications include pneumothorax, bleeding and re-expansion pulmonary oedema. Repeated accumulation requires a plan for its underlying cause and, where indicated, a longer-term drainage strategy.[ref] The durable principle is to compare the harm caused by the collection with the benefit and risk of the proposed procedure, rather than using a single physical sign as an automatic command to operate.