U rologic Applications of the Holmium

G e rry Sue Yo u n g R o b e rt Ball

The holmium laser has various urologic applications. It is import a n t ince its introduction in for urologic nu rses and associates to be familiar with the laser 1990, the holmium laser p hysics and safety recommendations of the holmium laser, as well as has proven its versatility. to understand the applications and surgical techniques associated The holmium laser was Sfirst introduced for use in with this therapy. o rthopaedics and has pro g re s s e d to use in many other serv i c e s including uro l o g y. The use of the t rons to a higher level, energ y tive and thermal damage is only holmium laser in urology has f r om outside the atom is 0.4 mm to 0.6 mm. The laser is expanded to include treatment of re q u i red. Stimulating the atoms p o rtable and does not re q u i re calculi, urothelial tumors, stric- with an outside source of energ y water hookups. It does re q u i re t u res, condyloma, ure t e ro c e l e s , excites electrons, “kicking” them special electrical power, most as well as other soft tissue appli- to a more distant orbit of higher often 208-volt, 30-amp, single- cations, possessing both ablative e n e rg y. “Excited” electrons har- power. and hemostatic pro p e rties. bor extra energ y. When electro n s Laser Safety Laser Physics “ d r op” back down into their g round state there is a sponta- Basic laser safety should Laser is an acronym for Li g h t neous emission of light radiation always be practiced when using Amplification by St i m u l a t e d (a photon) from the “excited” any laser. The holmium laser is a Emission of Radiation. The term atom. When many “excited” class IV laser. These pose is now used for laser devices that atoms are collected in a tube, h a z a r ds to eyes and skin. p roduce an intense cohere n t , their emissions of energy are P recautions to be taken when d i rectional beam of light by stim- amplified, and emerge as a laser using a class IV laser include ulated electronic or molecular beam. Diff e rent lasers take their using appropriate eyewear, label- transitions to a lower energ y names from the energy sourc e s ing doors, and covering any win- level. Each atom has a nucleus that are used to excite the atoms. dows while the laser is in use. containing positively charg e d The medically utilized Water should be readily avail- p rotons. Negatively charged elec- holmium laser emits a pulsed able. One should also have a fire t rons orbit the positively charg e d beam of 2,100 nm (nanometers) extinguisher available. Instru - nucleus. The usual charged state with a maximum power output ments used in the vicinity of the of the atom is balanced. The orbit of 60 watts. The laser energy is laser must be anodized or have a of each electron is associated d e l i v e red via a quartz fiber, either roughened surface in order to with a specific energy level. The an end-firing or side-firing re f r a c- avoid reflection which could g round state finds the electro n s tive 5.5 Fr fiber. There are four p roduce unwanted damage in a and protons close together in a d i ff e r ent sizes of end-firing n o n t a rgeted area. Endotracheal low energy state. To change elec- fibers: 200, 365, 550, and 1,000 tubes can be ignited by the laser m i c r on diameters, and one if they are flammable and come angled side-firing fiber. The ener- in contact with the laser beam. G e r ry Sue Yo u n g , R N , C N O R , i s gy is dispersed by both dire c t L a s e r- r esistant endotracheal Senior Nurse Specialist, Inova Fa i r fa x contact and noncontact modes. tubes should be used when the Hospital, Falls Church, VA . The fiber for the noncontact laser treatment area is close. mode must be kept less than 5 Laser plume can also be a con- R o b e rt Ball, M D, is a urologist with mm away from the tissue for tis- c e rn. Diff e rent institutions have Dominion Urological Consultants, Ltd., sue response. The beam’s energ y additional policies. At our insti- A n n a n d a l e, VA . transmission is noncolor selec- tution the laser safety off i c e r

254 UROLOGIC NURSING / December 1999 / Volume 19 Number 4 F i g u re 1. F i g u re 2. Bladder calculi. Laser fiber ready for treatment of largest bladder c a l c u l i .

e n f o rces the safety measures that O b s t ruc tion of the ureter by the place a stent. p rotect the patient and staff dur- stone may present diff i c u l t y ; Bladder calculi have always ing laser use. thus, a guide wire or other type of p resented problems with tre a t- h y d rophilic wire is used to gain ment secondary to their large size Use in Uro l o g y access to the kidney. Once access (see Figures 1 & 2). A bladder The first urologic use of the to the kidney is obtained, the sur- stone can grow to such a size that holmium laser dates to 1993 geon may opt to dilate the ure t e r it may re q u i re removal by an when ureteric calculi were tre a t- with a balloon dilator, dilating open surgical pro c e d u re. The ed by laser vaporization. Stone u reteral catheter, or a dual lumen holmium laser has proven quite disease involves appro x i m a t e l y u reteral catheter. A second guide useful in treating bladder calculi 10% of the typical urology prac- w i re may then be inserted. If a (Grasso, 1996). Either an end- fir- tice. There are several diff e re n t second wire is inserted, the sur- ing or the side-firing fiber can be types of stones. oxalate geon may then pass the ure t e ro- used to fragment the stone. and calcium phosphate compose scope over the second wire. If no Depending on size and composi- 80% of renal and ureteral calculi. second wire is used, the surg e o n tion, laser settings may vary. A Oxalate stones are divided into will pass the ure t e roscope along- beginning setting may be 0.6 to dihydrate and monohydrate. The side the guide (safety) wire. Care 1.0 joules with a pulse rate of 6 to noncalcium calculi include cys- is taken never to lose access to 10 Hz. If that setting makes the tine, struvite, and urate. the kidney. Once the calculus is stone “jump” too much, the The holmium laser is very visualized, the laser fiber is pulse rate may be lowere d . e ffective on all types of calculi passed through the working D i ff e rent techniques may be used ( S h ro ff et al., 1996). Following channel of the ure t e ro s c o p e . to get the bladder calculus to a a p p ropriate evaluation including Laser fragmentation of the calcu- manageable size. Slowly “paint- radiologic study to determine the lus is often begun with low ing” the calculus edges with the p resence, location, and size of a power settings such a 0.6 joules laser fiber to reduce the calculus calculus, the urologist must at 6 Hz (hertz). If the calculus layer by layer may be pre f e rre d to decide the proper tre a t m e n t . does not respond, the power or b reaking the calculus into small- Small caliber flexible and semi- f r equency may be incre a s e d . er pieces. As the calculus is rigid ure t e roscopes, combined Adjuncts to treatment include reduced in size it “jumps” more with newer, slimmer laser fibers placing the patient in a re v e r s e in the bladder causing more irr i- make laser treatment of distal Tre n d e l e n b u rg position to keep tation to the bladder lining. calculi common and often desir- the calculus from migrating pro x- Stone fragments must be totally able. Access to the stone is imally up the ureter into the kid- i rrigated from the bladder, often obtained by a variety of means. ney pelvis during lithotripsy. with an instrument such as a Depending on surgeon pre f e r- Once the calculus has been frag- Toomey and adapter or an Ellick ence, the ureteral orifice may or mented to a manageable size, the and adapter. Once all fragments may not be dilated prior to s u rgeon may then either discon- a re removed, a catheter may be u re t e ro s c o p y. A guide wire is tinue treatment, place a ure t e r a l i n s e rted to prevent urinary re t e n- i n s e rte d into the ure t e r. stent, or basket the stone, then t i o n .

UROLOGIC NURSING / December 1999 / Volume 19 Number 4 255 The holmium laser also has use in treating ure- F i g u re 3. thral and ureteral stricture disease (Razvi, Chun, A bulbar urethral stricture . Denstedt, & Sales, 1995). There are a number of causes of urethral strictures. Trauma and sexually transmitted disease are the most common. S t r i c t u res vary in size, length, and depth. When pursuing treatment of a urethral stricture it is desir- able to gain access to the bladder before beginning laser treatment. This may be accomplished by using a guide wire, filiform, or ureteral catheter. An angled or end-firing fiber may be used as the cutting tool. The proximity to the sphincter should be iden- tified. With the fiber extended from the cystoscope, a 12 o’clock incision is made into the urethral stric- t u re. This may be accomplished with an end-firing fiber by positioning the fiber into the tissue at the 12 o’clock position and dragging it through the tissue t o w a rd the cystoscope. When using the angled fiber it is positioned at 12 o’clock directly on the tissue and dragged toward the cystoscope. Similar cuts are made either in the same position or rarely at the 6 o’clock position until access to the bladder can be F i g u re 4. made with the cystoscope. Power is increased as the Laser fiber on the right of a bulbar urethral stric- of the scarred tissue becomes evident by its t u re. Ureteral catheter on the left. response to the laser. Laser settings usually start at 1 joule and a frequency of 10 Hz. Once the bladder is inspected, the ure t h rotomy is again assessed to a s s u re acceptable patency and hemostasis. When it is determined that the stricture is opened suff i c i e n t- l y, a catheter or Urolume prothesis is placed. If the U rolume prothesis is used a catheter is contraindi- cated. The holmium laser has also been used on u reteral strictures (see Figures 3-5) (Razvi et al., 1995). The laser is used much the same way it is for a ureteral calculus. A re t rograde pyelogram is done to determine the location and length of the ure t e r a l s t r i c t u re and rule out other pathology. A guide wire is placed up into the affected ure t e r. A ure t e ro s c o p y is perf o rme d and once the ure t e roscope reaches the s t r i c t u re site the laser fiber is advanced into the s t r i c t u red area then dragged back toward the u re t e roscope. Laser settings start at 0.6 joules with a rate of 6 to 10 Hz. After the stricture has been incised a ureteral stent is placed. F i g u re 5. The holmium laser has also been used to incise Bulbar urethral stricture following laser u re t e roc eles. The incidence of ure t e rocele is as high t re a t m e n t . as 1 in 500 (Coplan & Duckett, 1995). These con- genital malformations are cystic dilations of the submucosal portion of the intervesical ure t e r. They a re thus often not recognized unless other symp- toms such as infections occur which would then necessitate treatment. Ureteral calculi may also f o rm in ure t e roceles. In adults, they are usually associated with a single collecting system. Treatment re q u i res placing a ureteral guide wire fol- lowed by laser incision of the ure t e roc ele. An end or side-firing fiber can be used. Laser settings range f rom 1.0 to 1.2 joules at a rate of 10 Hz. Once the u re t e roc ele is incised and any calculus is extracted, a ureteral stent is placed. Soft tissue holmium laser applications include

256 UROLOGIC NURSING / December 1999 / Volume 19 Number 4 laser ablation of tumors, pro s t a t e fiber can be hand held or a laser tissue, bladder neck contracture s , hand piece can be used. and condyloma. Concern i n g P recautions pertaining to laser bladder cancer, the size and loca- plume and condyloma should be tion of the tumor determ i n e instituted. These pre c a u t i o n s which type of fiber can be used. include use of a smoke evacuator Laser tumor fulguration can be and special laser plume masks p e rf o rmed with the continuous along with the other laser safety flow laser resectoscope. Settings policies (“The Dangers of Laser for the laser start at 1.0 to 1.4 Plume,” 1990). joules with a rate of 10 to 14 Hz. Laser ablation of the pro s t a t e C o n c l u s i o n is used for benign prostate hyper- The holmium laser has plasia (BPH). BPH affects some p roven to be of great use in uro l- 18.5 million men (Razvi et al., o g y. As with other lasers, care 1995). Although the “gold stan- should always be taken, but the d a rd” for treating BPH is the holmium seems to be one of the t r a n s u r ethral resection of the safest lasers to use if the pro p e r p rostate (TURP), laser fulgura- p recautions are taken. • tion is an accepted altern a t e t reatment. Laser settings for tre a t- R e f e re n c e s ing the prostate start at 1.8 to 2.0 Coplan, D.D., & Duckett, J.W., (1995). The joules with a rate of 25 to 30 Hz. m o d e rn approach to ure t e ro c e l e s . J o u rnal of Uro l o g y, 153(1), 166-171. Again a continuous flow laser Grasso, M. (1996). Experience with the resectoscope may be used with holmium laser as an endoscopic the side-firing fiber. A side-firing lithotrite. Adult Uro l o g y, 98(2), 199- fiber should also be used for inci- 2 0 6 . Razvi, M., Chun, S.S., Denstedt, J.D., & sion of bladder neck contrac- Sales, S.L. (1995). Soft-tussue appli- t u res. Laser settings are usually cations of the holmium YAG laser in 1.2 to 1.4 joules with a rate of 10 u ro l o g y. J o u r nal of Endouro l o g y, to 14 Hz. 9(5), 367-390. Laser fulguration of genital S h ro ff, S., Watson, G.M., Parikh, L.A., Thomas, A., Soonawalla, P. F., & and urethral condyloma is also Pope, A. (1996). The holmium YA G practiced. The depth of laser laser for ureteric stones. B r i t i s h e ffect is 0.4 to 0.6 mm. Tre a t m e n t J o u rnal of Uro l o g y, 75(6), 836-839. settings begin at 0.6 joules with a The dangers of laser plume. (1990). rate of 10 Hz. A rate of 15 Hz Health Devices, 19(1), 4-19. should not be exceeded. The

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