Should coughing occur the flow niust lie stopped till this passes off, the needle or canula being left in .cilu; hut ex( essive or continuous coughing, dyspncea or pulmonary embarrassment is an indication that some hyper wmia or oedema of the lung is taking place, and the operator should withdraw the canula and trust to nature for the removal of the residual fluid, or repeat the operation after the lapse of several days.
Tapping when carefully performed is seldom accompanied or followed by any untoward event, but very occasionally air has been permitted to enter the pleural sac, which, however, need excite no anxiety when sterilisation of the instrument has been thorough, nor need any emphyse matous condition of the tissues in the immediate vicinity of the site of puncture cause alarm. Syncope is only likely to occur when the fluid has been drawn off too rapidly under a complete exhaustion of the cylinder or exhaust bottle; it may be anticipated in weak and nervous patients by a small dose of alcohol. Pneumothorax from puncture of the lung is one of the rarest complications, and if let alone will resolve. A more serious sequela is the appearance of albuminous expectoration the result of pulmonary oedema; this probably never occurs unless when the operator has been too anxious to remove all the fluid at a single tapping.
After the withdrawal of the canula a small pad of Iodoform gauze or a pledget of lint soaked in Friar's Balsam should be placed over the puncture and secured by a strip of adhesive plaster.
When the remaining fluid fails to disappear as already stated a subse quent tapping will be necessary, and this may require repetition. Some authorities recommend, when several tappings fail to prevent reaccumula tion, that the pleural cavity should be freely incised as in empyema, and drainage established though the fluid remains free from pus. The appear ance of pus in any subsequent tapping is a clear indication for the major operation.
Barr strongly recommends that after the evacuation of the fibrino serous fluid in acute pleuritic Sterilised Air should be injected. He advocates the employment of siphonage, and after the withdrawal of about half the fluid the air is injected in quantity equal to the removed fluid. The siphonage is then continued till the entire fluid is evacuated, after which 4 c.c. Adrenalin Solution (I in r,000) diluted with S to ro
normal saline is injected into the cavity, and in old patients more air is also introduced so as to make the total amount equal to half or three-fourths of the bulk of the fluid removed.
Nitrogen is preferred to air by Vaquez, being very slow of absorption, and he employs this gas alone without injecting adrenalin. It is claimed for these methods that reaccumulation of fluid never occurs, and the dangers of pulmonary oedema and dvspncea are avoided though the fluid is all drawn off at a single operation.
The operation is simplified by Achard. who allows ordinary air to enter the pleural cavity through the tube used in tapping at intervals during the withdrawal, trusting to the sterilisation of the air by permitting it to flow over the moistened interior of the rubber tubing. He admits almost as much air as removed fluid, and has never met with an instance of sepsis occurring.
Griinbaum and Pitt slowly inject into the pleural cavity 20 c.c. sterilised Liquid Paraffin after the evacuation of the fluid; the paraffin diffuses itself over the surface of the pleura, effectually preventing the formation of adhesions.
The treatment of pleural effusion must not stop with the removal of the fluid. The researches of past years have demonstrated the frequency with which the disease is associated with the presence of the tubercle bacillus in cases which formerly were accepted as of pneumococcal, streptococcal, or other microbic infection. Even if the theory be accepted that in many if not in most cases the supervention of phthisis is to be explained as a secondary event due to the injury of the pleural membrane by some simple inflammatory action, still the indications for further treat ment must be regarded as imperative. Open-air life, improved hygiene, and good living must be rigidly enforced as in every case of tuberculosis, and the earliest and fullest expansion of the compressed lung and of the retracted side of the thorax must be expedited by resorting to pulmonary gymnastic or vigorous breathing exercises carried out perseveringly and thoroughly for a long period. The best of these consists in blowing water from one Wolff bottle to another.