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Bladder Explosions During Transurethral Surgery
THE JOURNAL or lJROl,OGY Copyright© 1975 by The Williams & Wilkins Co.
Vol. 114, October
Printed in U.S.A.
BLADDER EXPLOSIONS DURING TRANSURETHRAL SURGERY THEODORE C. NING , ,JR.,* DALE M. ATKil\S
ANO
R. C. M URPHY
From the Division of Urology and Department of Pharmacology, University of Colorado Med ical Center, Denver, Colorado
ABSTl{ACT
Gases liberated during transurethral electrosurgery are common to all tissues, with hydrogen produced in high concentration. We postulate that the majority of hydrogen is derived from electrolysis of intracellular water. Only with the addition of outside oxygen does the gaseous mixture become potentially explosive. lntravesical explosions during transurethral operations have been mentioned only briefly in the literat ure yet all resectionists are aware of the occasional popping sounds and have seen bubbles arising from the resectoscope cutting element. Because of our extensive experience with bladder explosions we herein report 2 cases and the results of our investigation on the etiology of the problem using mass spectrometry. Analyzing gases from human bladders and an in vitro resection chamber, we determined the composition of the gases and noted the high concentration of hydrogen. Deuterium oxide (D 2 0) was used in an attempt to localize the hydrogen source. Preventive measures that exclude the presence of outside oxygen are described. CASE REPORTS
Case 1. Fulguration was done at the conclusion of a transurethral resection of the prostate and after irrigation of prostatic fragments. An audible explosion occurred and a tear was noted in the dome of the bladder. No intra peritoneal defect was found but suprapubic drainage was performed. The patient did well . Case 2. During resection of a tumor on the bladder dome we noted gas forming adjacent to the tumor base. Endoscopic examination after accidental detonation revealed a mucosa! tear. The patient was carefully monitored. No suprapubic drainage was performed. The patient did well. METHODS
Collection of gas samples. Samples of gases were taken at random from the bladders of patients Accepted for publication February 7, 1975. Read at annual meeting of South Central Section, American Urological Association, Denver, Colorado, September 15- 19, 1974 . Supported by United States Public Health Service Research Grant GM -20457 of the National Institutes of Health. * Requests for reprints: Divis ion of Urology, Box C:319, Univers ity of Colorado Medical Center, 4200 E ast Nint h Ave., Denver, Colorado 80220.
undergoin g transurethral resect ion of the prostate (using general and spinal anesthetics) . A coagatome ES-101 t electrosurgical unit and an ACMit resectoscope were used throughout all the experiments and 2.7 per cent sorbitol or distilled water served as the irrigation fluid. Gases that had collected in the dome of the bladder were aspirated at the conclusion of the operative procedure via a Foley catheter. Gases generated by electrosurgery of isolated human tissue were collected under irrigat ion fluid . These experiments served as an in vitro model for the transurethral resections. The gas collecting apparatus was composed of an inverted laboratory funnel over a container of the irrigation fluid and immersed approximately 1 cm. below the level of the fluid. A rubber septum cap was placed over the end of the funnel and the funnel was evacuated of room air by a syringe. The tissue was impaled on a steel wire connected to the electrosurgical unit and placed beneath the funnel. The tissue was then stroked with the resectoscope and the gases that were liberated displaced the fluid in the funnel stem. The gases were transferred by syringe to the mass spectrometer. Tissue preparation. Fresh prostatic adenoma was obtained from open prostatectomies. The tissue was not fixed but sliced into 3 by 1 by 1 cm. lengths and impaled on the steel wire electrode. Samples of the stomach, uterus and ovary were similarly obtained from surgical specimens and prepared for in vitro resection. Resection under D 2 0 . Uterine strips were obtained in the aforementioned manner. The strips were impaled and immersed in D 2 0 (bio-rad, 99.87 atom per cent 2 H) under the collecting apparatus. After immersion periods of 0, 10 and 30 minutes the strips were resected and each gas sample was collected for mass spectrometric analysis. The D 2 0 bath was then analyzed by mass spectrometry and
t Electro-Medical Systems, Inc., 8455 E. Prentice Ave., Englewood, Colorado 80ll0. :j: American Cystoscope M akers, Inc., 8 Pelham Parkway, New York, New York 10803.
536
t
537
BLADDER EXPLOSIONS DURING TRANSURETHRAL SURGERY
found to contain 74 per cent D20. Mass spectrometric analysis. Gas samples that had been collected in a 50 ml. plastic syringe equipped with a gas lock seal were transferred from the operating room to the mass spectrometry laboratory. The gas in the syringe was transferred to an evacuated 200 ml. glass gas sample bulb by standard gas handling techniques and an aliquot of this gas was further expanded into the 3 I. volume of the gas inlet system of a CEC 21-621 mass spectrometer. The gas at a pressure of 75 to 90 µm. was introduced into the ion source of the mass spectrometer via a gold leak . The mass spectrometer was then scanned in the low mass mode to detect ions from masses 1 to 4 and in the high mass mode for ions 12 to 140. The figure shows mass spectra (70 eV) from a sample of bladder gas (part A of figure) and normal room air (part B of figure) for comparison. Hydrogen was quantitated by the signal height at mass 2 in the bladder gas samples and a calibration curve of known pressures of commercial hydrogen gas. The concentrations of other gases were estimated from the signal heights 18, 26, 28 and 32, which were summed and set equal to the percentage of gas remaining after subtraction of the H 2 percentage. This method is only accurate to 10 to 50 per cent of the reported values for these
additional gases, which is well within the variation experienced from identical aliquots. The limiting factor in the quantitative analysis seemed to be the care exercised in not allowing liquid water from the irrigation fluid to be introduced into the glass expansion bulb and , thus, producing a large partial pressure of water . RESULTS
Samples of gases generated by electrosurgery in 8 patients were obtained for analysis. A representative mass spectrum of bladder gas from 1 patient and a mass spectrum of ordinary room air are presented in the figure for comparison. The ions in the figure at masses 1 and 2 are formed from hydrogen, 16 from methane, 18 from water, 26 from acetylene, 28 from diatomic nitrogen. carbon monoxide and ethylene, 32 from diatomic oxygen, 44 from carbon dioxide and the relatively less abundant ions at 43, 41, 39, 29, 27 and 15 in part A of the figure are ions from a mixture of other hydrocarbon gases. The major component gas is at mass 2, which is diatomic hydrogen and is absent in normal room air. The gas samples from other patients differed greatly in relative abundance of hydrogen ( mass 2) to nitrogen-oxygen (masses 28 and 32), whereas the ratios of hydrogen to carbon dioxide, methane and
A.
Bl.1.dder-
Gas
I I
L I
C 2H?
o,
svvv,,,~-~,~~ u1
L - - - - - -- ,.1
44
40
):?
1 26
28
I I! I
,LJ~c~~,~·~ ~ 18
N2 Room Air
32
28
18
14
MASS
t
538
NI NG. ATKINS Al\iD MURPHY
acet ylene remain rather constant. The total percentage of hydrogen ranged from 10 to 60 per cent of t h e gases . This variation was owing to t he difficulty in collect ing the gases , d ifferent a n es thetics, room air int roduced by manual irrigations with the evacuator and from t he irrigation tubing. To eliminate this problem of room air introduction and to a llow studies as to t he source of hydrogen , an in vitro system was devised. The collection apparatus a llowed evaluation of whether the generation of t he gas during electrosurgery was a non-specific phenomenon or dependent on the irrigation fluid and prostate t issue. Tahle 1 summarizes these studies. The data show that the evolution of vast quantities of hydrogen (50 to 60 per cent of the gases released) is not changed when distilled water or a sorbitol solution is used to bathe the tiss ue, nor is it changed when stomach , uterus or ovary tissue (rather than prostate) is resected . T he variation in the abundance of wa ter (mass 18) is a n artifact of the gas sample introduction system, which allows liquid water to be inadvertently pulled into the gas sampling syringe and be converted to gaseous water, reducin g the percentage of hydtogen in the gas mixture. Thus , these studies indicate t hat t he generation of gases during electrosurgery is a phenomenon of cauteri zation of tissues in general. Table 2 summarizes an experiment in which D 2 0 was used to bathe uterine strips for the in vitro study. If the hydrogen gen erated during the electrosurgery came solely from the irrigation fluid , the h ydrogen generated would be deuterium gas of mass 4 (D 2 ) . If t he hydrogen came solely from organic molecules in the tissue s uch as the hydrogen-rich p hospholipids of cell membra nes , the h ydrogen generated would not be influenced by the D 20 and thus h ave a mass of 2 (H 2 ) . The uterine strips were immersed in D 2 0 and gases were generated from them at 0, 10 and 30-minute intervals. The results indicated a gradual increase in D 2 incorporation into the hydrogen gas from ::is atom per cent D t o 44 atom per cent D as seen by the increase of ions at masses 3 (H-D) a nd 4 (D2lThe D 20 purity at the end of the experiment had dropped to 74 atom per cent D because of mixing of the intracellular water with t he D20 bath. This would suggest that a higher concentration of D2
TABLE
would have been formed if the D 2 0 purity were not dropping. DISCUSS ION
Only 4 cases of bladder explosions have been reported. 1 - 3 In I9'.l5 Hambleton and associates presented a quantitative ana lysis of gas es obtained during electrocoagulation of dog prostate.• They concluded t hat hydrogen was t h e explos ive component when mixed with a ir. Because of the low amperage (500 ma .). they believed that the gases were derived from therma l decompos ition of tissue, not electrolysis. Although the quantitative methods t hey used ,;ould seem to be subject to inaccuracies, simila r results have been obtained by our mass s pectrometric a nalys is . The studies report ed here have shown that the generat ion of hy drogen and other gases such as ca rbon monoxide and acety lene are a general phenomenon of t he -electrosurgery. It is not known if the source of t he potentially explosive gas, hydrogen, is from electrolysis or thermolytic decomposition of tissue. M easurem ent of the voltage and current generated by the apparatus during the in vitro studies indicated that more t han 500 volts and 500 ma. are routinely obta ined . T he instrument settings were identical to those used during transurethral resections. Since the voltage necessary for the electrolysis of water is onl y 1.7 t o 2.3 V, elect rolysis of water must be considered as a possible source of hydrogen. The experiments of electros urgery in D20 revealed t hat 1 source of hydrogen was related in a time-dependent manner to the water bathing t he tissue. This would indicate that s imple electrolysis of extracellular water is not the predominant 2. Time-course study of hydrot;en species released durint; electrosurt;erv of ut erus strips un der D,O
TABLE
T ime (mins.l
()
10
:io
Percent age of Total Hydrogen H,
HD
D,
5 1.7 47.6 35 .7
27. t :1:1.4
:io.9
4(U )
2:L:l
lso10pe Abunda nces Atom Per Cent H
Atom P er Cent D
6[,.4 64.4 56.2
34 .6 35 .6 4:l.8
18 .9
1. Gases released durint; in vitro electrosurgery of various tissues P ercent age of Gas Liberated
T issue
Fluid Bath H,
Prostate Prostate Stomach Ovary Uterus
W ater Sorbitol:j: Sorbitol Sorbitol Sorbitol
H,O
54 58
1
42
20
51 45
6 12
CO("l,, C,H,)*
o,
co,
Acetylenet
30 29 27
2 I
4
8 7 5
:12
:io
2 :l 2
4 4
:i 5
6 7
* Tbe species CO , N , a nd C,H , have the same nominal mass a nd could not be sepa rately analyzed by the mass s pectro met er used . t The value for acetylene includes other hydrocarbon gases which cont ri bute onl~· 5 t o 25 per cent of t h is value. :j: Sorbitol solution 2.7 per cent.
539
BLADDER EXPLOSIONS Dl'RINC TRANSCRETHRAL SURGE RY
mechanism by which hydrogen is liberated, perhaps involving only 35 per cent of the generated hydrogen. In addition, since the carbon-hydrogen bonds of phospholipids are complet ely nonexchangeable, this would rule out a major cont ribution of hydrogen from the thermal decomposition of plasma membranes and other organic constituents of cells. The known cellular processes involving exchangeable protons that are time-dependent in the time scale (10 to 30 minutes) seen here are relatively few. The most likely is the equilibration of intracellular and extracellular water. Therefore, we believe that a tentative hypothesis for the source of hydrogen would be the electrolysis of intracellular water.
vented without rupture or tearing of the bladder.' Adair has noted 2 explosions during transurethral prostatectomies us ing trocar cystostomy with no apparent bladder injury. 8 The perfusion of the system with an inert gas as described in electrocautery of bowel lesions via sigmoidoscopy would hinder visualization and necessitate constant evacuations .• Addition of absorptive agents to the irriga tion fluid to bind hydrogen or oxygen would be impract ical because of the inefficiency, possible toxicity and expense of such agents. REFERENCES
1. Kretschmer. H . L.: lntravesical explosions as a com-
PREVENTION OF EXPLOSIONS
Pure hydrogen atmospheres are not explosive. It is only after the addition of oxygen that hydrogen becomes explosive. Our experiments indicate that if no air were introduced into the system by air bubbles passing into the irrigation system, by manual irrigations or by opening of the resectoscope, a bladder tumor could be resected within the gas bubble. If it is necessary to open the system, inspection of the forming gas bubble is necessary with frequent manual evacuations as described by Baumrucker' and Blandy.• Ureteral catheter aspiration of the gas and positioning of the patient to move the gas bubble from the area of resection are also useful in preventing the highly undesirable explosions. Trocar cystostomy in the dome would allow escape of the forming gas and, should an explosion occur, the pressure would be
2. :l.
4.
5.
6.
7. 8. 9.
plication oft ransurethral electrorcsect inn: report of 2 cases . J.A.M.A., 10:l: 1144. 19:14. Cassuto. A.: Explosion clans la vess ie au cours d'une electro-coagu lation. J. d 'Urol., 22: 263. 1926. Hobhitt. H. M.: !ntraves ica l rupture of bladde r durin g t ransuret hral pros ta t ic resection. ,J. Urol., 64: 3:J8, 1950. Hambleton. B. F .. Lackey. R. W. and Van Duzen, R. E.: Explos ive gases formed durin g electrotransuretrral resection. ,J.A.M.A., 105: 64fi. 19:15. Haumrucker. G. 0.: TlJR-Transuret hral Prostatectomy: T echnique. Hazards. a nd Pitralls. 1st ed. Baltimore: The Williams & Wilkins Co., p. 61. 1968. Blandy, ,J. B.: Transurethra l Resection. 1st ed. Baltimore: University Park Press, p. 96, 197:2. Adair, E. L.: Suprapuhic shunt. ,J. Urn!., 108: 449, 1972. Adair, E. L.: Personal communieat ion. Levy, E. I.: Explosions during lowe r bowel electrosurgerv: method of prevention. Am e r. ,J. Surg., 88: 754, 19"-l.
t
Vol. 114, October
Printed in U.S.A.
BLADDER EXPLOSIONS DURING TRANSURETHRAL SURGERY THEODORE C. NING , ,JR.,* DALE M. ATKil\S
ANO
R. C. M URPHY
From the Division of Urology and Department of Pharmacology, University of Colorado Med ical Center, Denver, Colorado
ABSTl{ACT
Gases liberated during transurethral electrosurgery are common to all tissues, with hydrogen produced in high concentration. We postulate that the majority of hydrogen is derived from electrolysis of intracellular water. Only with the addition of outside oxygen does the gaseous mixture become potentially explosive. lntravesical explosions during transurethral operations have been mentioned only briefly in the literat ure yet all resectionists are aware of the occasional popping sounds and have seen bubbles arising from the resectoscope cutting element. Because of our extensive experience with bladder explosions we herein report 2 cases and the results of our investigation on the etiology of the problem using mass spectrometry. Analyzing gases from human bladders and an in vitro resection chamber, we determined the composition of the gases and noted the high concentration of hydrogen. Deuterium oxide (D 2 0) was used in an attempt to localize the hydrogen source. Preventive measures that exclude the presence of outside oxygen are described. CASE REPORTS
Case 1. Fulguration was done at the conclusion of a transurethral resection of the prostate and after irrigation of prostatic fragments. An audible explosion occurred and a tear was noted in the dome of the bladder. No intra peritoneal defect was found but suprapubic drainage was performed. The patient did well . Case 2. During resection of a tumor on the bladder dome we noted gas forming adjacent to the tumor base. Endoscopic examination after accidental detonation revealed a mucosa! tear. The patient was carefully monitored. No suprapubic drainage was performed. The patient did well. METHODS
Collection of gas samples. Samples of gases were taken at random from the bladders of patients Accepted for publication February 7, 1975. Read at annual meeting of South Central Section, American Urological Association, Denver, Colorado, September 15- 19, 1974 . Supported by United States Public Health Service Research Grant GM -20457 of the National Institutes of Health. * Requests for reprints: Divis ion of Urology, Box C:319, Univers ity of Colorado Medical Center, 4200 E ast Nint h Ave., Denver, Colorado 80220.
undergoin g transurethral resect ion of the prostate (using general and spinal anesthetics) . A coagatome ES-101 t electrosurgical unit and an ACMit resectoscope were used throughout all the experiments and 2.7 per cent sorbitol or distilled water served as the irrigation fluid. Gases that had collected in the dome of the bladder were aspirated at the conclusion of the operative procedure via a Foley catheter. Gases generated by electrosurgery of isolated human tissue were collected under irrigat ion fluid . These experiments served as an in vitro model for the transurethral resections. The gas collecting apparatus was composed of an inverted laboratory funnel over a container of the irrigation fluid and immersed approximately 1 cm. below the level of the fluid. A rubber septum cap was placed over the end of the funnel and the funnel was evacuated of room air by a syringe. The tissue was impaled on a steel wire connected to the electrosurgical unit and placed beneath the funnel. The tissue was then stroked with the resectoscope and the gases that were liberated displaced the fluid in the funnel stem. The gases were transferred by syringe to the mass spectrometer. Tissue preparation. Fresh prostatic adenoma was obtained from open prostatectomies. The tissue was not fixed but sliced into 3 by 1 by 1 cm. lengths and impaled on the steel wire electrode. Samples of the stomach, uterus and ovary were similarly obtained from surgical specimens and prepared for in vitro resection. Resection under D 2 0 . Uterine strips were obtained in the aforementioned manner. The strips were impaled and immersed in D 2 0 (bio-rad, 99.87 atom per cent 2 H) under the collecting apparatus. After immersion periods of 0, 10 and 30 minutes the strips were resected and each gas sample was collected for mass spectrometric analysis. The D 2 0 bath was then analyzed by mass spectrometry and
t Electro-Medical Systems, Inc., 8455 E. Prentice Ave., Englewood, Colorado 80ll0. :j: American Cystoscope M akers, Inc., 8 Pelham Parkway, New York, New York 10803.
536
t
537
BLADDER EXPLOSIONS DURING TRANSURETHRAL SURGERY
found to contain 74 per cent D20. Mass spectrometric analysis. Gas samples that had been collected in a 50 ml. plastic syringe equipped with a gas lock seal were transferred from the operating room to the mass spectrometry laboratory. The gas in the syringe was transferred to an evacuated 200 ml. glass gas sample bulb by standard gas handling techniques and an aliquot of this gas was further expanded into the 3 I. volume of the gas inlet system of a CEC 21-621 mass spectrometer. The gas at a pressure of 75 to 90 µm. was introduced into the ion source of the mass spectrometer via a gold leak . The mass spectrometer was then scanned in the low mass mode to detect ions from masses 1 to 4 and in the high mass mode for ions 12 to 140. The figure shows mass spectra (70 eV) from a sample of bladder gas (part A of figure) and normal room air (part B of figure) for comparison. Hydrogen was quantitated by the signal height at mass 2 in the bladder gas samples and a calibration curve of known pressures of commercial hydrogen gas. The concentrations of other gases were estimated from the signal heights 18, 26, 28 and 32, which were summed and set equal to the percentage of gas remaining after subtraction of the H 2 percentage. This method is only accurate to 10 to 50 per cent of the reported values for these
additional gases, which is well within the variation experienced from identical aliquots. The limiting factor in the quantitative analysis seemed to be the care exercised in not allowing liquid water from the irrigation fluid to be introduced into the glass expansion bulb and , thus, producing a large partial pressure of water . RESULTS
Samples of gases generated by electrosurgery in 8 patients were obtained for analysis. A representative mass spectrum of bladder gas from 1 patient and a mass spectrum of ordinary room air are presented in the figure for comparison. The ions in the figure at masses 1 and 2 are formed from hydrogen, 16 from methane, 18 from water, 26 from acetylene, 28 from diatomic nitrogen. carbon monoxide and ethylene, 32 from diatomic oxygen, 44 from carbon dioxide and the relatively less abundant ions at 43, 41, 39, 29, 27 and 15 in part A of the figure are ions from a mixture of other hydrocarbon gases. The major component gas is at mass 2, which is diatomic hydrogen and is absent in normal room air. The gas samples from other patients differed greatly in relative abundance of hydrogen ( mass 2) to nitrogen-oxygen (masses 28 and 32), whereas the ratios of hydrogen to carbon dioxide, methane and
A.
Bl.1.dder-
Gas
I I
L I
C 2H?
o,
svvv,,,~-~,~~ u1
L - - - - - -- ,.1
44
40
):?
1 26
28
I I! I
,LJ~c~~,~·~ ~ 18
N2 Room Air
32
28
18
14
MASS
t
538
NI NG. ATKINS Al\iD MURPHY
acet ylene remain rather constant. The total percentage of hydrogen ranged from 10 to 60 per cent of t h e gases . This variation was owing to t he difficulty in collect ing the gases , d ifferent a n es thetics, room air int roduced by manual irrigations with the evacuator and from t he irrigation tubing. To eliminate this problem of room air introduction and to a llow studies as to t he source of hydrogen , an in vitro system was devised. The collection apparatus a llowed evaluation of whether the generation of t he gas during electrosurgery was a non-specific phenomenon or dependent on the irrigation fluid and prostate t issue. Tahle 1 summarizes these studies. The data show that the evolution of vast quantities of hydrogen (50 to 60 per cent of the gases released) is not changed when distilled water or a sorbitol solution is used to bathe the tiss ue, nor is it changed when stomach , uterus or ovary tissue (rather than prostate) is resected . T he variation in the abundance of wa ter (mass 18) is a n artifact of the gas sample introduction system, which allows liquid water to be inadvertently pulled into the gas sampling syringe and be converted to gaseous water, reducin g the percentage of hydtogen in the gas mixture. Thus , these studies indicate t hat t he generation of gases during electrosurgery is a phenomenon of cauteri zation of tissues in general. Table 2 summarizes an experiment in which D 2 0 was used to bathe uterine strips for the in vitro study. If the hydrogen gen erated during the electrosurgery came solely from the irrigation fluid , the h ydrogen generated would be deuterium gas of mass 4 (D 2 ) . If t he hydrogen came solely from organic molecules in the tissue s uch as the hydrogen-rich p hospholipids of cell membra nes , the h ydrogen generated would not be influenced by the D 20 and thus h ave a mass of 2 (H 2 ) . The uterine strips were immersed in D 2 0 and gases were generated from them at 0, 10 and 30-minute intervals. The results indicated a gradual increase in D 2 incorporation into the hydrogen gas from ::is atom per cent D t o 44 atom per cent D as seen by the increase of ions at masses 3 (H-D) a nd 4 (D2lThe D 20 purity at the end of the experiment had dropped to 74 atom per cent D because of mixing of the intracellular water with t he D20 bath. This would suggest that a higher concentration of D2
TABLE
would have been formed if the D 2 0 purity were not dropping. DISCUSS ION
Only 4 cases of bladder explosions have been reported. 1 - 3 In I9'.l5 Hambleton and associates presented a quantitative ana lysis of gas es obtained during electrocoagulation of dog prostate.• They concluded t hat hydrogen was t h e explos ive component when mixed with a ir. Because of the low amperage (500 ma .). they believed that the gases were derived from therma l decompos ition of tissue, not electrolysis. Although the quantitative methods t hey used ,;ould seem to be subject to inaccuracies, simila r results have been obtained by our mass s pectrometric a nalys is . The studies report ed here have shown that the generat ion of hy drogen and other gases such as ca rbon monoxide and acety lene are a general phenomenon of t he -electrosurgery. It is not known if the source of t he potentially explosive gas, hydrogen, is from electrolysis or thermolytic decomposition of tissue. M easurem ent of the voltage and current generated by the apparatus during the in vitro studies indicated that more t han 500 volts and 500 ma. are routinely obta ined . T he instrument settings were identical to those used during transurethral resections. Since the voltage necessary for the electrolysis of water is onl y 1.7 t o 2.3 V, elect rolysis of water must be considered as a possible source of hydrogen. The experiments of electros urgery in D20 revealed t hat 1 source of hydrogen was related in a time-dependent manner to the water bathing t he tissue. This would indicate that s imple electrolysis of extracellular water is not the predominant 2. Time-course study of hydrot;en species released durint; electrosurt;erv of ut erus strips un der D,O
TABLE
T ime (mins.l
()
10
:io
Percent age of Total Hydrogen H,
HD
D,
5 1.7 47.6 35 .7
27. t :1:1.4
:io.9
4(U )
2:L:l
lso10pe Abunda nces Atom Per Cent H
Atom P er Cent D
6[,.4 64.4 56.2
34 .6 35 .6 4:l.8
18 .9
1. Gases released durint; in vitro electrosurgery of various tissues P ercent age of Gas Liberated
T issue
Fluid Bath H,
Prostate Prostate Stomach Ovary Uterus
W ater Sorbitol:j: Sorbitol Sorbitol Sorbitol
H,O
54 58
1
42
20
51 45
6 12
CO("l,, C,H,)*
o,
co,
Acetylenet
30 29 27
2 I
4
8 7 5
:12
:io
2 :l 2
4 4
:i 5
6 7
* Tbe species CO , N , a nd C,H , have the same nominal mass a nd could not be sepa rately analyzed by the mass s pectro met er used . t The value for acetylene includes other hydrocarbon gases which cont ri bute onl~· 5 t o 25 per cent of t h is value. :j: Sorbitol solution 2.7 per cent.
539
BLADDER EXPLOSIONS Dl'RINC TRANSCRETHRAL SURGE RY
mechanism by which hydrogen is liberated, perhaps involving only 35 per cent of the generated hydrogen. In addition, since the carbon-hydrogen bonds of phospholipids are complet ely nonexchangeable, this would rule out a major cont ribution of hydrogen from the thermal decomposition of plasma membranes and other organic constituents of cells. The known cellular processes involving exchangeable protons that are time-dependent in the time scale (10 to 30 minutes) seen here are relatively few. The most likely is the equilibration of intracellular and extracellular water. Therefore, we believe that a tentative hypothesis for the source of hydrogen would be the electrolysis of intracellular water.
vented without rupture or tearing of the bladder.' Adair has noted 2 explosions during transurethral prostatectomies us ing trocar cystostomy with no apparent bladder injury. 8 The perfusion of the system with an inert gas as described in electrocautery of bowel lesions via sigmoidoscopy would hinder visualization and necessitate constant evacuations .• Addition of absorptive agents to the irriga tion fluid to bind hydrogen or oxygen would be impract ical because of the inefficiency, possible toxicity and expense of such agents. REFERENCES
1. Kretschmer. H . L.: lntravesical explosions as a com-
PREVENTION OF EXPLOSIONS
Pure hydrogen atmospheres are not explosive. It is only after the addition of oxygen that hydrogen becomes explosive. Our experiments indicate that if no air were introduced into the system by air bubbles passing into the irrigation system, by manual irrigations or by opening of the resectoscope, a bladder tumor could be resected within the gas bubble. If it is necessary to open the system, inspection of the forming gas bubble is necessary with frequent manual evacuations as described by Baumrucker' and Blandy.• Ureteral catheter aspiration of the gas and positioning of the patient to move the gas bubble from the area of resection are also useful in preventing the highly undesirable explosions. Trocar cystostomy in the dome would allow escape of the forming gas and, should an explosion occur, the pressure would be
2. :l.
4.
5.
6.
7. 8. 9.
plication oft ransurethral electrorcsect inn: report of 2 cases . J.A.M.A., 10:l: 1144. 19:14. Cassuto. A.: Explosion clans la vess ie au cours d'une electro-coagu lation. J. d 'Urol., 22: 263. 1926. Hobhitt. H. M.: !ntraves ica l rupture of bladde r durin g t ransuret hral pros ta t ic resection. ,J. Urol., 64: 3:J8, 1950. Hambleton. B. F .. Lackey. R. W. and Van Duzen, R. E.: Explos ive gases formed durin g electrotransuretrral resection. ,J.A.M.A., 105: 64fi. 19:15. Haumrucker. G. 0.: TlJR-Transuret hral Prostatectomy: T echnique. Hazards. a nd Pitralls. 1st ed. Baltimore: The Williams & Wilkins Co., p. 61. 1968. Blandy, ,J. B.: Transurethra l Resection. 1st ed. Baltimore: University Park Press, p. 96, 197:2. Adair, E. L.: Suprapuhic shunt. ,J. Urn!., 108: 449, 1972. Adair, E. L.: Personal communieat ion. Levy, E. I.: Explosions during lowe r bowel electrosurgerv: method of prevention. Am e r. ,J. Surg., 88: 754, 19"-l.
t