< // // // //

Case 69: Urgent underwater seal-drain

Whilst working at a small country hospital you are faced with a 32 year old man involved in a farming accident. He has been charged by a bull and one horn has penetrated his right chest. An xray shows haemo-pneumothorax. You have inserted an intercostal catheter but the hospital does not have a modern drain chamber to connect it to. The nurses find some old glass chambers and rubber tubing that they used when the hospital was better funded 20 years ago.

1. How would you connect the tubing to create a standard 3 chamber system with 20 cm water suction?

The first chamber is simply to drain any haemoserous fluid. The second provides an underwater seal to allow air to readily escape the chest but not reflux back in. The third chamber allows control of negative suction pressure being applied to the lung and pleural cavity. By altering the height of the column of water the negative pressure within this chamber that is transmitted to the chest can be altered.

2. What is the significance of bubbles appearing in chamber A on the drain above?

Chamber A is the suction chamber therefore bubbles simply mean that it has been connected to suction. The air enters the chamber through a vent to atmosphere. In contrast bubbles appearing in chamber C, the underwater seal chamber, indicate air escaping from the chest through the ICC. Initially this occurs as the lung re-expands and the pneumothorax is evacuated. If these bubbles persist, and are best demonstrated on coughing, then this indicates ongoing airleak from a bronchopleural fistula.

3. What is the significance of "swinging" and where would you look for it?

Swinging represents the pressure changes occuring within the chest with normal respiration. These pressure changes are transitted along the tubing and may be seen as swinging of any fluid contained within the tubing. Swinging can also be seen as the fluid level in chamber C alters. It simply indicates that the system is patent and not occluded.

Case Editor: