Your patient's chest tube dressing has accidentally come off. What additional item do you need to properly place a new dressing?

When placing a new dressing on a patient's chest tube site, the use of petroleum gauze is essential for effectively sealing the area and preventing air from entering the pleural space, which could lead to serious complications such as a tension pneumothorax. Petroleum gauze serves as a barrier that allows air to escape but prevents it from re-entering, thereby maintaining the proper function of the chest tube and protecting the wound from external contaminants.

The choice of petroleum gauze is particularly important in this scenario because it adheres well to the skin and provides an occlusive layer that is crucial in managing open chest wounds.

Using other options like an adhesive bandage would not provide the necessary occlusive properties needed for a chest tube site. Mineral oil and wet gauze do not serve the purpose of creating a suitable dressing for the drainage site, as they do not form a seal and might actually promote infection or other complications. Thus, petroleum gauze is the correct and most effective material to use when re-dressing a chest tube.