12. Chest Drainage: Underwater Seal or Chest Drainage System

There are three parts to this section:

1 Insertion of an underwater seal chest drain

2 Changing a chest drainage bottle

3 Removal of an underwater seal chest drain

Learning outcomes

By the end of this section, you should know how to:

▪ support and prepare the patient for these three nursing practices

▪ collect and prepare the equipment necessary to insert a chest drain and connect it to underwater seal drainage, change a chest drainage bottle and assist with removal of an underwater seal chest drain

▪ assist the medical practitioner in parts 1 and 3

▪ care for the patient who has a chest drain connected to underwater seal drainage.

Background knowledge required

Revision of the anatomy, physiology and pathology of the respiratory system, including the structures of the chest wall

Revision of ‘Aseptic technique’ (seep. 386).

Revision of local policy on chest drainage.

1. INSERTION OF AN UNDERWATER SEAL CHEST DRAIN

Indications and rationale for insertion of an underwater seal chest drain

Chest drainage refers to a closed system of drainage that allows air or fluid to pass in one direction only, from the pleural space to either a collecting bottle or flutter valve system. It may be required in a variety of situations when ventilation is impaired, such as traumatic injuries, malignancy, post-thoracic surgery or following spontaneous collapse of the lung (pneumothorax). Chest drainage may therefore be used to remove air, blood, fluid or pus from the pleural space to improve ventilation capacity.

Chest drains may also be inserted to allow drug administration to occur, for example in lung cancer.

The choice of drainage system will depend upon the clinical status and underlying condition of the patient, the nature of the expected drainage and whether the drain is being inserted perioperatively or in a ward or outpatient unit. Underwater seal drainage bottles are at risk of being knocked over, inhibit patient mobilisation and need to be monitored on an inpatient basis. Flutter valve systems are useful for draining air though they cannot be used for draining fluid. The flutter valve system has the advantage of allowing mobilisation.

The drain insertion site will also vary according to the clinical status of the patient. Confirmation of the insertion site should be made following clinical examination and chest X-ray in all cases, apart from tension pneumothorax when it would be a priority to insert the drain quickly. Sometimes the drain is inserted with the aid of imaging such as ultrasound (Laws et al 2003). For many of the indications for chest drain insertion, the site will be the third, fourth or fifth intercostal space in the mid axillary line.

Position of the patient

During insertion, the patient’s clinical status will determine the optimum position to be adopted. It is often sitting upright and the patient may use a table with a pillow to rest on.

Outline of the procedure

Using an aseptic technique, the medical practitioner cleanses the patient’s skin with iodine or an alcohol-based antiseptic (as per local skin preparation policy), over the selected site of entry for the drain, injects a local anaesthetic and waits for it to take effect. The method of drain insertion will vary depending on the size of drain required. The aim is to avoid excessive force that may cause damage to intrathoracic structures. Sometimes an introducer is used, or blunt dissection of the subcutaneous tissue using forceps may be used for larger sizes of drainage tube. Once the tube is in place, the medical practitioner connects the drain to the equipment already prepared by the nurse. A suture is inserted round the entry site of the drain to seal the site off when the drain is eventually removed. A purse-string suture should not be used (Laws et al 2003). A sterile transparent dressing is placed over the site to help to prevent infection of the small wound (Fig. 12.1).