U R I 



U R I 



Sir E. Home and Mr. Hatchett firft fuggefted the utility 

 of giving magnefia in cafes of ftone, and the propofal was 

 communicated to the public by Mr. Brande. ( Phil. Tranf. 

 1810. ) It is, as Dr. Marcet obferves, often found advan- 

 tageous in long protrafted cafes, in which the conftant ufe of 

 the fubcarbonated or cauftic alkalies would injure the fto- 

 mach. But, he properly remarks, that if magnefia is fome- 

 times beneficial, it has of late years often done harm. For, 

 as this earth is the bafe of one of the moft common fpecies 

 of calculi, the ammoniaco-magnefian phofphate, there is 

 nearly an even chance, when magnefia is prefcribed, without 

 any pretious knowledge of the nature of the calculus, that 

 it will prove injurious. Magnefia alfo, when obftinately ad- 

 miniftered,fometimes forms large maflesin the inteftinal canal, 

 caufing ferious diftrefs, and even fatal confequences. 



According to Dr. Prout, purgatives will fometimes ftop 

 calculous depofitions, efpecially in children ; and Dr. Henry, 

 of Nfenchefter, has obferved, that a quack medicine, com- 

 pofed of turpentine and opium, will occafionally produce a 

 plentiful difcharge of lithic acid from the bladder. 



For many of the foregoing obfervations, we are indebted 

 to Dr. Marcet's interefting Eflay on the Chemical and Medi- 

 cal Treatment of Calculous Diforders, London, 1817. Some 

 other remarks on injedlions, as a means of difTolving calculi 

 in the bladder, and on hthontriptics in general, will be 

 found in the article Lithotomy. 



Urinary FiJluU. See Fistul.e In Perinao, and Um- 

 NARY Abjceffes. 



Urinary Paffage. See Urethra. 

 URINE, in Phyfiology, the fluid fecreted by the kidney. 

 See Kidney. 



Urine, Bloody. See Hematuria. 

 Urine, Incontinence of. An incontinence of urine is 

 when this fluid comes away from the patient involuntarily, 

 without his having any power of retaining it. The difordcr 

 is one to which children are particularly liable ; adults are 

 lefs frequently afiliiEled with it ; and it is a cafe which feldom 

 occurs in perfons of very advanced years. The latter afler- 

 tion, as Default remarks, mud appear erroneous to thofe 

 who frequently meet with old perfons unable to retain their 

 urine, were it not well afcert oined, that patients often millake 

 for an incontinence of urine the overflowing of this fluid 

 out of the urethra, in cafes of retention, of which that occur- 

 rence is only a fymptom. There are even fome furgeons, 

 fays Default, who imbibe this popular error, and feem 

 unaware that an involuntary difcharge of urine may exift 

 together with a retention, and be the efleft of it, as is gene- 

 rally the cafe in fuch retentions as depend upon weaknefs 

 and paralyfis of the bladder. In thefe inftances, the dif- 

 tended fibres of this vifcus reaft upon the urine which then 

 iflues from the urethra, until the refiftance of the fphinfter 

 and of the canal is in equilibrium with the expelUng power. 

 Sometimes the urine even dribbles awav inceffantly, which 

 happens whenever the aftion of the bladder has been com- 

 pletely deftroyed ; for, in tliis ftate, this vifcus being con- 

 Ilantly full, cannot receive any more of the urine that is 

 brought to it by the ureters, unlefs an equal quantity at the 

 fame time efcape through t!ie urethra. This is a cafe 

 which will more properly fall under confideration in the ar- 

 ticle Urine, Retention of, and we need not therefore dwell 

 upon it at prefent. 



The caufes of an incontinence of urine, properly fo called, 

 are diametrically different from thofe of a retention. The 

 latter cafe happens whenever the bladder becomes weak, and 

 the refifl:ance in the urethra increafed. An incontinence, on 

 the other hand, arifes either from the expelling power of the 

 bladder being augmented, while the rcfiitance in the urethra 



is not proportionably increafed ; or from the reQftance 

 being leflened, while the expelling force remains unchanged. 

 According to thefe principles, it is eafy to explain why the 

 diforder fliould be moll common in children. At this age, 

 it is well known that there is more irritability than at any 

 other period of fife. It is alfo well knowi; that the expul- 

 fion of the urine is entirely effefted by mufcular aftion, 

 while the refiftance is merely owing to the fphinfter veficse, 

 the levatores ani, and perhaps to a few other inconfiderable 

 fafcicuh of mufcular fibres ; for the different curvatmes of 

 the urethra, and the contraftile power of this tube itfelf, can 

 make but a paffive and feeble refiftance to the iffue of the 

 urine. An incontinence happens in children, becaufe the 

 bladder contrafts fo fuddenly and forcibly, that its contents 

 are voided almoft before thefe young fubjefts are aware of 

 any defire to make water, and without their being able to 

 reilrain the evacuation. There are alfo many children who, 

 from indolence or careleffnefs, do not make water imme- 

 diately the firft calls of nature incite them, and who after- 

 wards, being urgently prefled, wet their clothes. In other 

 young fubjetts, the fenfation which makes the bladder con- 

 traft, and accompanies the expulfion of the urine, is fo flight, 

 that the funAion is performed without any formal adl of the 

 will, without even exciting an impreffion fufficiently ftrong 

 to difturb fleep. This is the cafe with fuch children as are 

 troubled only with an incontinence of urine in the night-time. 

 Increafing years, by diminifliing the irritability of the blad- 

 der, and making man more attentive to his neceflities, ufually 

 bring about a cure of the infirmity, which feldom continues 

 till the patient has attained the adult ftate. 



It muft not be fuppofed, however, that no period of life 

 excepting childhood can be ;iffliftcd with the complaint. 

 Other ages are alfo liable ; but then the diforder almoft al- 

 ways depends upon a defeft of refiftance to the iffue of the 

 urine, and it may be occafioned by weaknefs, or paralyfis of 

 the fphinfter veficx, or levatores ani : fometimes, alfo, by 

 a forcible dilatation of the urethra, and lofs of its elaf- 

 ticity. Frequently all thefe caufes are at the fame time 

 concerned. 



A calculus, a fungus, or any other extraneous body of an 

 irregular fliape, may be fixed in the neck of the bladder, and 

 not accurately filling it, may allow the urine to efcape at the 

 fides ; or the foreign body may even form forts of channels, 

 through which the fluid pafles. 



Frequently, alfo, a violent contufion or forcible diftention 

 of the iphintter is followed by an incontinence of urine. 

 The complaint ufed to be very common formerly after the 

 mode of lithotomy called the apparatus major ; and it is 

 even at prefent not an unufual confequence of the extraftion 

 of calculi from females by the dilatation of the meatus urina- 

 rius. (See Lithotomy.) The neck of the bladder and 

 the urethra are forcibly diftended in thefe operations, and, 

 confequently, they lofe their contrattile power, continue di- 

 lated, and no longer duly oppofe the efcape of the urine. 



Women who have had difficult labours, and in whom the 

 child's head, by compreffing the neck of the bladder, has 

 ferioufly contufed and weakened this part, are alfo fubjeft 

 to a fpecies of incontinence of urine ; which, however, is in 

 general only experienced when they laugh, or make any 

 confiderable exertion. 



Moil authors, who have treated of incontinence of urine, 

 have relattd, that perfons afflifted with palfy and apoplexy 

 are very liable to the complaint. But, as we have already 

 explained, they have heremiftaken what the French furgeons 

 aptly call the "retention d' urine avec regorgement," for an 

 incontinence. In this fort of cafe, the fame writers have 

 attributed the involuntary difcharge of the urine to paralyfis 



of 



