Respiratory disorders in palliative care

The main respiratory disorders observed during the palliative phase are:

Dyspnoea,
Coughing,
Bronchial congestion.

Other respiratory disorders are mainly observed during lung cancer:

Superior vena cava syndrome
Haemoptysis,
Pleural effusion,
Proximal airway obstruction.

 Dyspnoea:

Definition

Dyspnoea or shortness of breath is a subjective, toilsome and agonising sensation of suffocation. It induces major modifications in respiratory rhythm and respiratory time ratio.
It is difficult to quantify but is generally a poor prognostic factor.

Physiopathology

Several effectors are involved during dyspnoea modifying respiration:

• central chemoreceptors (acidosis),
• peripheral carotid and aortic chemoreceptors sensitive to hypoxia,
• thermoreceptors of the superior airways,
• bronchial and pulmonary mecanoreceptors (which may be sensitive to opioids),
• muscle mecanoreceptors (diaphragm and thoracic muscles)..

Etiology

Several causes are easy to diagnose (and sometimes to treat):

• pneumopathy (decubitus pneumopathy, superrinfection pneumopathy or due to oesotracheal fistula),
• pleural or pericardial effusion,
• airway obstruction through adenopathy, metastasis or primitive lung tumour,
• lymphangitis carcinomatosous (particularly during breast cancer progression
• anaemia,
• cardiac or vascular disease (acute or subacute pulmonary oedema, pulmonary embolism),
• ascitis,
• phrenic paralysis.

Aetiological treatments

Tumour obstruction justifies (when feasible) chemotherapy or decompressive radiotherapy. When an isolated bronchial or tracheal obstruction exists, laser treatment may clear the airway for at least a period of time. Another efficient method may be the insertion of an endoprosthesis.

Infectious pneumopathies require antibiotics that are well adapted to germs.

Effusions may be punctured (except in genuinely terminal phases).
Anaemia may be corrected by blood transfusion or erythropoietin injections.

Symptomatic treatments

Several treatment modalities are useful:

Morphine is a good treatment for dyspnoea. The following effects are described:

reduced receptor sensitivity (implied in the dyspnoea sensation): the signal is cut if the clinical situation cannot be improved,

reduced respiratory rhythm (reduced dead space),

reduced muscle fatigue generating dyspnoea anxiety,

reduced cardiac rhythm with reduced reactional hypertension on the peripheral and pulmonary circuit.

Precise monitoring of respiratory function is mandatory (to avoid overdosage).

Corticosteroids are major adjuvant drugs..

Scopolamine helps to reduce bronchial hypersecretion.

Anxiolytic drugs reduce anxiety and respiratory frequency.

The use of oxygen is highly debatable: many caregivers prefer using fresh air, sitting the patient in front of a window, for fear of a paradoxal effect of oxygen (stopping the respiratory stimulus),

other caregivers use it at low concentration.

No precise study has ever demonstrated the interest of oxygen but patients and their families often request it.

Coughing:

Principle

Coughing is a reflex mechanism that protects airways: it should therefore theoretically be respected.

However, when it becomes chronic and when no aetiological treatment is available, coughing can lead to dyspnoea, muscle pain, insomnia, vomiting or even conjunctival or nasal haemorrhage or headache.

It is exhausting for the patient.

Physiopathology

Many sensitive zones provoke coughing and any lesion of these structures may result in severe coughing:

larynx and cavum,
trachea,
bronchi,
pleura and pericardium.

Aetiology

During palliative care, coughing may result from:

The initial pathology

bronchopulmonary carcinoma, mesothelioma, neoplastic pleural effusion, lymphangitis carcinomatosis

A complication of the initial pathology

(coughing may be the revealing symptom)
superinfectious pneumopathy,
pulmonary embolism,
atypical acute oedema,
iatrognic (chemotherapy induced) or spontaneous cardiac insufficiency.

Aetiological treatments

Same reasoning as for dyspnoea: all feasible treatment is administered.

Symptomatic treatments

Two different situations:

Cough producing sputum (see next page on bronchial effusion)

When the patient is able to cooperate:

physiotherapy,
fluidifying nebulisation (or hydration with a nebuliser): acetylcysteine, dornase alpha,
fluidifying agents by general route: bromhexine,
regular aspiration

If patient can no more cooperate::

use of drying agent to reduce mucus production:
opioid, (see below),
antihistaminic and anticholinergic: alimemazin, dexchlorpheniramine or sodium cromoglicate

Dry cough

use of β-2 mimetic bronchodilator agents:

either by general route or by inhalation: terbutaline, salbutamol,

opioid cough suppressant

mainly codeine,
if the patient is already receiving opioids for pain, the dose could be increased (up to 50%) then decreased when coughing is under control.

non opioid cough suppressant

dextromethorphane bromhydrate , clobutinol,

high dosage corticosteroids (for treating the irritation of pleura or diaphragm by the tumour),

local anesthetic: lidocaine or bupivacaine, with all the required care to avoid false passages (the effect on coughing lasts longer than the anaesthetic effect on deglutition).

Bronchial congestion :

Definition

Bronchial congestion is in relation with abnormal production of bronchial mucus with or without coughing.

Clinical aspects

The circumstances of bronchial congestion together with the aspect of sputum enable us to distinguish the origin of bronchial congestion:

simple chronic bronchitis (non-puriform expectoration),
infectious bronchopneunomathies (puriform expectoration),
vomica of pulmonary abcess with or without blood

Treatment

Strong antibiotherapy should be instituted in the case of pulmonary infection.
Otherwise, treatment is the same as for coughing.

If the patient is able to expectorate

Coughing should be respected

If the patient is unable to expectorate

If the patient can cooperate: regular suctions should be performed, either with a tube or during fibroscopy,

If the patient is exhausted (or in terminal phase): mucosa must be dried:

scopolamin butylbromure or bromhydrate used in patch form, offering rapid sedation for around 4 hours,

atropine (in nebulisation).

Superior vena cava syndrome :

Aetiology

Superior vena cava syndrome is related to cancer in almost 90% of cases and especially to lung cancers (among them small cell carcinoma).

Other frequently responsible cancers are: lymphoma, breast cancer, mediastinal geminal tumours, thymoma and various others.

Due to the anatomical configuration, superior vena cava syndrome is observed four times more frequently on the right.

Differential diagnoses are rare: idiopathic mediastinal fibrosis, histoplasmosis, venous thrombosis related to a catheter or surgery. In fact, all pathological processes which invade or destroy the lymph structures of the superior mediastinum may provoke an obstruction to the return of venous blood and thrombosis.

Clinical presentation

Its onset is generally insidious.

Its severity depends on:

• rapidity of the obstructive process,
• thrombosis syndrome,
• precise location of the obstruction,
• possibility and rapidity of the constitution of collateral circulation.

Venous hyperpressure of the entire upper body is observed with venous distension, laryngeal oedema, increased intracranial pressure, cerebral oedema. All of these symptoms, if not treated (or if treated too late), may be fatal.

The revealing patient complaint is dyspnea, coughing, headache and facial swelling. Then, neck, chest and upper limb swelling is observed. All of these symptoms are worsened when the patient bends forwards. Diagnosis is evident as soon as this is evoked.

In reality, the development of superior vena cava syndrome is rarely acute (most often neglected). Half of the patients reveal their cancer through this syndrome. Chest radiography and thoracic scan are the best imaging procedures before a diagnostic biopsy.

You can view a typical case of superior vena cava with thrombosis and important collateral circulation.

Treatment

Most cancers, which are discovered via this syndrome, are more and less chemosensitive (small cell lung cancer, lymphoma, germ tumours). Chemotherapy is therefore the choice treatment. In less chemosensitive tumours, radiotherapy may be a good palliative option.

Other palliative measures are semi-seated position, rest, oxygen and short courses of corticosteroids.
A poor response to aetiological and palliative treatment suggests concurrent thrombosis which may require further anticoagulant treatment.

Unfortunately, most superior vena cava syndromes relapse since underlying cancer is not cured by treatment (lung cancer). The use of intravenous stents has been suggested in order to avoid acute complications.

 Hemoptysis:

Small and moderatly abundant hemoptysis

They generally do not necessitate specific emergency measures. Bronchofibroscopy may permit finding the origin of hemoptysis and potentially propose a specific treatment (even in palliative non terminal phase).

For instance, local treatment by pulmonary artery embolisation or by laser or by endobronchial brachytherapy or by external radiotherapy and if necessary and feasible a simple surgical intervention.

Massive hemoptysis

Massive bronchial haemorrhage (hemoptysis) is rarely involved in patient death in lung cancer. The flooding of the bronchial tubes is far more life-threatening than the actual quantity of blood lost.
The most frequently concerned cancer is epidermoid lung cancer since it invades blood vessels and is highly necrotic.

Another frequent cause of hemoptysis is pulmonary aspergillosis which often occurs in immunodeprived patients (after prolonged chemotherapy).

More rarely, hemoptysis is related to therapy (laser, endobronchial brachytherapy).
Treatment includes very simple measures such as adopting a semi-seated position, oxygenation, aspiration, and a rapid search for the aetiology (bronchosopy if the patient’s status permits).
In terminal hemoptysis, patient anxiety should be relieved (subcutaneous morphine, midazolam), and a carer/family member should remain at the patient’s bedside until sleeping.

If no efficient aetiological treatment is possible (surgery for instance), various techniques have been proposed such as a Fogarty catheter, arterial embolisation, radiotherapy or laser beam.

Pleural effusion:

Clinical aspects

The main clinical symptoms of pleural effusion are dyspnoea, coughing and thoracic pain. Diagnosis is established on clinical examination by percussing and sounding the patient's thorax (X-ray chest radiography corroborating the clinical diagnosis).

The causes are not always related to cancer:

left ventricular insufficiency,
atelectasis,
pulmonary embolism.

All cancer types may provoke pleural effusion, which generally relapses after puncture. The most frequent localisations are:

bronchopulmonary cancer,
breast carcinoma,
lovarian carcinoma,
mesothelioma.

Puncture 

Evacuating pleural effusion by puncture allows confirmation of diagnosis and offers information for determining aetiology.

 It is a very interesting therapeutic procedure since it generally relieves patient dyspnoea very rapidly.

If pleural effusion is massive, the first evacuation should generally be limited to approximately one litre in order to prevent a feared 'a vacuo' pulmonary oedema.

Even during the preterminal phase, an evacuating puncture may offer genuine relief to the patient.

Talc pleurodesis

Long before the terminal phase, the patient will be profoundly affected by the often rapid relapse of pleural effusion, involving pain but, more importantly, increasing dyspnoea. The patient's quality of live and relative well being are therefore considerably altered.

In these cases, talc pleurodesis may be performed:

either by the thoracic drain (blind pleurodesis)
or during pleuroscopy.

The major hindrance to complete pleurodesis is a multiple partitioned effusion: in order to obtain a large diffusion of talc into the pleural cavity, pleural effusion should be relatively abundant before the procedure.

This therapeutic procedure is well tolerated, and is generally not painful. It is a rapid procedure with a low rate of benign complications (light fever during the first 48 hours).

Efficiency is very high since pleural drainage may last several months for 90 to 95% of patients. This procedure should therefore be proposed when potential survival is above one month.
 
A few contraindications should be respected: non re-expanding lung (after puncture), lung having lost its elasticity through lymphangitis carcinomatis or severe post-radiotherapy sclerosis or when diffuse pleural metastases are present.The major hindrance to a complete pleurodesis is a multiple partitioned effusion: in order to obtain a large diffusion of talc into the pleural cavity, pleural effusion should be relatively abundant before the procedure.

Proximal airways obstruction :

Clinical aspects

Proximal airway obstruction is most often a respiratory emergency: there are no obstructive symptoms until the tracheal or main bronchial calibre is reduced by more than 80%.

Main symptoms include: bradypnea, stridor (inspiration with acute noise), crowing noise, wheezing and symptoms of obstructive pneumopathy.

Except in the very last terminal phase, rapid relief should be offered to the patient (even if only for a few months).

Therapeutic modalities

Surgery should remain exceptional (at the very onset of disease).
Chemotherapy is rarely efficient except on lymphoma and small cell lung carcinoma (at the onset of disease).

Yag laser beam

The procedure is performed through a flexible fibroscope.Its efficiency is immediate.However, obstruction should be symptomatic and no longer than 4 cm along the bronchial tree.

The endoscopist should be able to perceive the bronchial hole and the downstream lung should be functional.

Laser is not indicated for extrinsic compression or in the case of an oesotracheal fistula.

Endoprosthesis 

Here again, efficiency is immediate.

The endoprosthesis is installed through endoscopy.

It is efficient on extrinsic compression, however stenosis should not be wide enough to enable its introduction.

Endobronchial brachytherapy. 

Its effect is not immediate.

It can complete the laser action and avoid relapse for patients with longer survival prognosis (a few months) and can be performed even after external irradiation.

Other local techniques may be used (such as phototherapy, cryotherapy, thermocoagulation) which are very useful in the experienced hands of physicians working with a palliative intent.