THE Operation for the Empyema generally implies an artificial Opening made into the Cavity of the Thorax, by which we evacuate any Fluid that lies there extravasated, and is become dangerous by its Weight and Quantity. The Fluids described as necessary to be voided by this Operation, are Blood, Matter, and Water. When Blood is the Fluid, supposed to require Evacuation by this Method, 'tis always extravasated through some Wound of Vessels of the Lungs or Thorax, and being discharged in great Quantities on the Diaphragm, is said to oppress Respiration till let out by some convenient Opening, made in the most depending Part of that Cavity, which is the only kind of Perforation into the Thorax distinguished by the Name of the Operation for the Empyema: But though this Opening is universally recommended in the Case here stated, yet we meet with few or no Examples where it has been practised for a mere Extravasation of Blood; and I should think it can hardly ever be adviseable on this Account: For if we perform it immediately after the Accident, and during the Hæmorrhage, the Opening made at the Bottom of the Thorax, might probably make way for a dangerous Effusion of Blood, which perhaps would otherwise be choked up and stopped for want of a ready Issue; and if we wait till the Hæmorrhage ceases, it becomes needless because the Blood not only for the most part, finds some Vent by the external Wound, if left open, but is constantly spit up by the Trachea; so that had we no farther Proofs of this absorbent Power in the Lungs, we might from hence be persuaded of the Probability of its being more safely carried off so, than by any artificial Opening we can possibly contrive in the Thorax.

Or if it be thought that the extravasated Blood, being coagulated in the Thorax, cannot be taken up by the Vessels of the Lungs, yet even in that case, the Operation usually practised will not answer the Purpose; for besides the possibility of the Lungs adhering to the Pleura in the place of lncision, which would absolutely prevent any Advantage from it, the Depth and Narrowness of the Orifice, and its Height above the Diaphragm, on which the congealed Blood is supposed to lie, will make the Success at best but very precarious.

To empty the Thorax, in a Rupture of any Vessels which open into it, Bleeding is very necessary, which not only stops the Hæmorrhage, by abating the Force of the Circulation but likewise, by unloading the Vessels of their Contents, makes them more fit to receive the extravasated Fluid by Absorption: gentle Evacuations and Pectorals are also very serviceable, and a low Diet is absolutely necessary.

The Rules laid down in some Books for distinguishing if a Wound penetrates, have led Practitioners into mischievous Methods, by advising them to examine these Wounds with the Probe, or for more certainty the Finger; which if rudely used sometimes even tear into the Thorax, always force or press the Parts too much, and often separate the Lungs from the Pleura, when they happen to adhere; All Which Violences will produce Abscesses there, especially if the Part be afterwards dressed with large Tents, or filled with any active Injection, both which were formerly applied with a View to deterge the Cavity of the Wound, but now seem to be exploded in favour of more superficial Dressings; the Advantages of which Method, in my Opinion, cannot be too much inculcated.

But what I have here advanced concerning the Excellence of superficial Applications, without dilatlng the Wound, to make way for the Issue of the Blood or succeeding Matter, must be considered with regard to Punctures or Incisions by sharp Instruments, not followed with a great Discharge: For where the Wound is made by Fire-arms, the Method of Practice must be sometimes altered; because not only Sloughs, and great Suppurations ensue, but very often Pieces of the Shirt or Coat are carried in with the Bullet, which will perhaps require an Enlargement of the Wound, in order to be freely discharged; though even upon this Account, there will be no Occasion to make an Opening at the Bottom of the Thorax, since the mere Dilatation of the Wound will more readily give vent to the Pus and extraneous Bodies, than An Orifice made lower; because the Lungs, being inflamed by the Wound, will generally adhere to the Pleura, and break off the Communication between the Abscess and the Cavity below it. In dressing the dilated Wound, Care must be taken to apply the Dossils with such Pressure only as shall be sufficient to keep open the external Orifice; and not to crowd them into the Thorax, so as to lock up that Matter, which the very Design of Dilatation is to give a Discharge to.

The second Circumstance in which this Operation takes place is a Rupture of Matter from the Pleura, Mediastinum or Lungs, into the Cavity of the Thorax, where accumulating, it at length proves fatal for want of a Discharge. It is true that the Case occurs but very seldom, where the Operation is necessary; because in most Abscesses of the Thorax, the Matter is usually spit up as fast as it is generated, and in the Dissection of such who have died of this Species of Consumption, we rarely find much extravasated Pus in the Cavity, tho' a great Portion of the Lungs be destroyed: However as I have intimated, there are a few Examples which require the Operation: and these may be distinguished by the following Symptoms. The Patient is obliged to lie upon the diseased Side, or in case there is Matter in both Cavities of the Thorax, on his Back; because the Mediastinum can seldom support the Weight of the incumbent Fluid, without suffering great Pain; but this Rule is not certain, it sometimes happening that the Patient can lie with ease on that Side, where there is no Fluid. Another Symptom of extravasated Matter, is an evident Undulation of it, so that in certain Motions, it may be heard to quash. For the most part too upon careful Enquiry, an Oedema, or at least a thickening of some Portion of the Intercostal Muscles will be discovered. And lastly, if there be much fluid, it will be attended with preternatural Expansion of that Side of the Chest, where it lies. When therefore these Signs appear after a previous Pleuretic or Pulmonary Disorder, and the Case has been attended with the Symptoms of a Suppuration, it is most probably owing to a Collection of Matter; though the Patient will also labour under a continual low Fever, and a particular Anxiety from the Load of Fluid.

I have here described the Abscess as breaking into the Cavity of the Thorax; but generally speaking, in any Inflammation of the Pleura or Lungs, an Adhesion of both ensues; in Consequence of which, Nature finds a Discharge outwardly, it being most frequent for Abscesses of the Pleura and intercostal Muscles, and not uncommon even for Abscesses of the Lungs, to break externally. In case of an Adhesion, no farther Operation is required than opening the Tumour when suppurated, with a Lancet; and if the Discharge be so great as to forbid the healing the external Ulcer, it may be kept open with a hollow Tent; by which manner of Treatment many have lived a long Time with a running Fistula.

The last Sort of Fluid said to require Issue from this Operation is Water, which however very seldom collects in such manner as to become to become the proper Subject of the Operation; for if the Dropsy of the Thorax be complicated with an Anasarca, or even Ascites, It is certainly improper, and indeed it can hardly ever take place, but where the Distemper is single, and takes its Rise from the same sort of Disorder in the Lymphaticks of the Pleura, as the Hydrocele does from those of the Tunica Vaginalis. The Symptoms of this Dropsy are, a small Cough without Spitting, a little slow Fever from the Disturbance of Respiration; sometimes too the Water by a sudden jerk may be heard to quash, and generally speaking its Weight upon the Diaphragm and Mediastinum are so troublesome as to oblige the Patient to stoop forward when in an erect Posture, and to turn upon the affected Side when he lies down; for the same Reason, when there is Water in both Cavities of the Thorax, he is forced to lie on his Back.

The Manner of operating, whether it be for the Discharge of Matter or Water, is to pitch upon the most depending Part of the Thorax, which some have supposed to be between the eighth and ninth Rib, and others between the ninth and tenth, at such a Distance from the Vertebra, that the Depth of the Flesh may not be an Impediment to the Perforation. This Distance is determined to be about a Hand's Breadth; and here, with a Knife, Scissars, or Trocar, we are ordered to make the Perforation; but in doing it, there are a great many Difficulties: In fat Persons, it is not easy to count the Ribs, and the Wound will be Very and troublesome to make; it is hardly possible to escape wounding the intercostal Artery, which, runs in this Place between the Ribs; or if you avoid it, by cutting close to one of the Ribs, a Caries of the Bone will follow from the Pressure of the Tent employed afterwards: Again, the Inflammation of the Wound may possibly affect the Diaphragm, which is supposed amost contiguous to it, and this may prove of very ill Consequence so that, upon the whole, without any farther Recital of Objections to the Empyema thus performed, it cannot appear an adviseable Operation. But if the only Advantage, proposed by this Situation of the Wound, be derived from its Dependency; the Purpose of discharging the Fluid will be as well answered, by an Opening between the sixth and seventh Rib, half way from the Sternum towards the Spine; which by laying ourselves down, becomes in effect as depending an Orifice, as the other in sitting Up; and by an Opening made in this manner, we avoid all the Inconveniencies in the other Method: For in this part of the Thorax, there is very little Depth of Muscles; the Artery lies concealed under the Rib; and the Diaphragm is at a a great Distance; so that none of those Mischiefs can ensue I have supposed in the other Method; which consequently will give it the Preference. The Opening is best made with a Knife, and should be about an Inch long thro' the Skin, and half an Inch through the subjacent Muscles: tho' to make the Incision with less Risk of wounding the Lungs, it may be adviseable to dilate it with the blunt-pointed Knife, (as is practised in the Operation for the Bubonocele), after having made a small Puncture with a common Knife. If it should be objected, that The Fluid cannot be discharged by this Orifice, while we are erect, whereas by making it in the lower Part of the Thorax, it will be continually draining; I think it may be answered, that after it is once emptied, it will hardly in twelve Hours be generated in greater Quantity than what will lie upon the Diaphragm below the Opening made even by that Operation, and consequently cannot be more readily discharged by one Orifice, than the other. The Treatment of the Wound will be according to the Nature of the Discharge. If after a few Days, there appears no Drain, you may let the Orifice heal up, but if it continue it may be kept open with a short silver Canula, 'till, such time as an Alteration in that Circumstance will give us leave to cicatrize with Safety.