65.2 Draining the pleural cavity

Drainage is all that a patient with a chest injury usually needs. Remove air by putting a tube into the top of his pleural cavity, usually in his third intercostal space just lateral to his midclavicular line. Drain blood, fluid, or pus from the bottom, usually through his eighth or ninth space in his posterior axillary line. The easiest way to prevent air entering his chest is to lead the tubes from it under the surface of the water in a large bottle (Tudor–Edwards bottle). The principle of this is shown in A, Fig. 65-5. Air from his chest will bubble up from under the surface of the water, without allowing more air to enter. Any fluid in his chest will drip down the tube into the water. Provided the bottle is always well below the patient’s bed, water from it cannot enter his chest. If he has both air and fluid in his pleural cavity, some surgeons would put one tube low in his chest and allow air and fluid to bubble out together as froth. Wiser ones insert two tubes.

Here is the equipment for a chest drain set. The life of one medical student was saved after an elephant had punctured his lung, because a tiny clinic had a chest drain set ready. Here is the equipment for it. Have it instantly ready, you will need it in a hurry.

•NEEDLES, hypodermic, large for chest aspiration, 1.6100 mm, ’Luer–lok’ mount each, five only. This mount fits the three way stopcock listed below, and is a useful aspirating and exploring needle.

•STOPCOCK, for chest aspiration, ’Luer–lok’ male to ’Luer-lok’ female, with side arm for tubing, two only. Use this for aspirating the chest.

•SYRINGES, 5 ml and 20 ml, both ’Luer–lok’ These fit the stopcock.

•BOTTLE, Tudor–Edwards, 3 litres, chest drainage, including rubber bung and tubes, one only. This provides an underwater seal for closed drainage of the chest.

•CONNECTOR, for Tudor–Edwards chest drain, five only. This completes the equipment for an underwater chest drain.

•Alternatively, CHEST DRAIN SET, plastic, disposable, sterile, in packet complete, five only. You will not use a chest drain set very often, so the modest expense of a disposable one may be justified.

The first step is usually a diagnostic aspiration to make sure that a patient really does have fluid in his chest. After this, there are various ways you can put a tube in the chest. The easiest one is to push a large trocar and cannula between his ribs to remove the trocar, and then to push a plastic or rubber tube down the cannula. The cannula is then removed leaving the tube in place. If you don’t have a suitable cannula, you can stab his chest wall with a scalpel and then use artery forceps to push a tube through an intercostal space. Always: (1) Take the strictest aseptic precautions. It is tragic to convert a haemothorax to pyohaemothorax, or to introduce new strains of bacteria into an empyema. (2) Prevent more than the minimum amount of air entering his pleural cavity.

The alternatives described below do not include the use of a drip set to drain the chest, because: (1) the tube of a drip set is too narrow so that it is easily blocked, and (2) the needle is usually too short to reach the fluid.