Intravesical pressure during irrigating fluid absorption in transurethral resection of the prostate

OBJECTIVE: In order to control fluid absorption, various approaches are used to reduce intravesical pressure during transurethral resection of the prostate (TURP). With a view to finding a target pressure for such efforts, pressure and fluid absorption were compared in a meta-analysis of four previous studies comprising three different irrigation techniques. MATERIALS AND METHODS: Intravesical pressure was recorded during TURP in which the irrigating fluid was evacuated intermittently (n = 48) by a suprapubic tube (n = 23) or a trocar (n = 30). Fluid absorption was compared with the mean and maximum pressures and the duration of excessive pressure (>2 kPa) over 10-min periods. RESULTS: Mean bladder pressure during fluid absorption was between 1.0 and 2.5 kPa. The maximum pressure during absorption varied greatly during the first 30 min of TURP, but thereafter it ranged between 2 and 3 kPa. Only the duration of pressures >2 kPa increased with fluid absorption (p < 0.02). The maximum pressures were highest with the intermittent technique, while the other indices of intravesical pressure showed the highest values when the suprapubic tube was used. The lowest pressures usually occurred when the trocar was used, but fluid absorption still occurred, as the pressure was much higher during some of these operations. CONCLUSIONS: Fluid absorption occurred at moderate intravesical pressures with all three irrigation techniques. The best strategy for reducing fluid absorption is to keep the pressure below 2 kPa for as long as possible during TURP.     

Analysis of the absorcion's factors of irrigating fluid during transurethral resection of the prostate

ObjetivesIn this study it was our intention to evaluate the relation between the reabsorption of irrigating fluid and three variables: time of the intervention, volume of solution of glicina employee and weight of the fragments, during the RTU of prostate fulfilled to low hydraulic pressure.Material and methodWe Study 74 patients that RTU of prostate was performed with suprapúbica derivation with Amplatz’s pod 30 ch. The ethanol was monitored in expired air every 15 minutes during the intervention. Likewise we annotated the time of the intervention, the volume of glicina used and the weight of the fragments extracted. Statistically Anova’s text was in use for comparison of averages.Results13,6 % of the patients absorbed irrigating fluid in some quantity. The range of absorption belongs to 100 cc until 2.000 cc. We did not find a statistically significant difference in the averages of time of resection, volume of glicina and weight of the fragments between the group of patients that had absortion of irrigating fluid and they that didn´t had.ConclusionsOur data show that the operative time, the volume of irrigating fluid and the weight of the resected fragments do not influence the reabsorption of liquid of irrigation when a RTU is realized to low hydraulic pressure.     

The use of distilled water as an irrigating fluid in patients undergoing transurethral resection of the prostate

Thirty patients undergoing transurethral resection of the prostate using distilled water as an irrigating fluid were studied. There was no significant change in the serum concentration of the variables studied (preoperatively compared to postoperatively) as possible indicators of haemolysis or absorption of irrigating water such as sodium, potassium, albumin, total protein, creatinine, uric acid, urea, haemoglobin, haematocrit and haptoglobin. The mean value of plasma haemoglobin (P-Hb), observed immediately postoperatively and reflecting the magnitude of haemolysis, was delta 294.8 mg/l. There was a good correlation between P-Hb and the inflowing irrigating distilled water (r = 0.69). The P-Hb variation (delta) correlated with resection time and with the weight of the resected prostate (r = 0.54 and r = 0.52, respectively). A good correlation was also found between resection time and delta body weight which reflects the amount of water absorbed (r = 0.67) and between delta body weight and the inflowing irrigating water (r = 0.61). Our study shows that distilled water can be used as an irrigating fluid quite safely. The advantages of distilled water outweigh the disadvantages which can be avoided easily if proper attention is given.     

Experience with hypotonic 2.5% sorbitol solution as an irrigating fluid in transurethral resection of the prostate

19 patients were studied in connection with transurethral resection of the prostate using the intermittent technique and hypotonic 2.5% sorbitol solution as an irrigating fluid. No diuretics were given postoperatively. In 2 patients there was a slight elevation of the serum creatinine level preoperatively but in 17 patients serum creatinine was within the reference limits. The plasma sorbitol concentration was determined at 20-min intervals for two hours. The mean plasma concentration of sorbitol immediately postoperatively was 379 mg/l (2.1 mmol/l) and the highest level observed was 1,900 mg/l (10.6 mmol/l). The half-life for sorbitol in plasma was 21 min (mean calculated in 11 cases). The range was 11-33 min. With increasing immediate postoperative plasma sorbitol levels there was also an increase in the half-life, corresponding to saturation of the sorbitol metabolizing enzyme system. The absorbed fluid volumes were calculated from the immediate postoperative plasma concentration of sorbitol, which gave a mean of 0.23 1 and a maximum of 1.01. Haemodilution effects with decrease in the serum sodium and serum albumin concentrations were noted, but they were much less marked than when 5% sorbitol solution was used as an irrigating fluid. There were only insignificant increases in the plasma haemoglobin concentrations postoperatively, which were probably due to heat decomposition of red blood cells in the bladder during the operation. About 7% of the absorbed amount of sorbitol was eliminated in the urine (mean). The highest value observed was 18% in the case showing the highest plasma sorbitol concentration immediately postoperatively (1,900 mg/l). Sorbitol was eliminated in the urine over a period of 6 hours postoperatively.     

The addition of ethyl alcohol to the irrigating fluid. Monitoring fluid absorption during transurethral resection of the prostate]

The absorption of irrigation solution during transurethral prostatic resection may lead to the life-threatening condition of the so-called TUR syndrome. For a long time no early recognition procedure was easily and routinely available. This study was set up to investigate the effectiveness of ethanol as an early indicator of beginning absorption, as described by Hulten. Ethanol was therefore added to the irrigating fluid as a marker, and alcohol concentrations were measured in the exhaled breath. METHODS. For measurement of alcohol an Alcotest monitor 7110, Dr?gerwerk (Lübeck, FRG) was used. In preliminary experiments with 13 healthy volunteers the lowest amount of measurable i.v.-administered 2% Ringer-ethanol solution was found to be about 200 ml. The irrigating fluid used was a 2% ethanol-mannitol/sorbitol solution. RESULTS. The control of breath and blood alcohol levels in 10 patients undergoing transurethral bladder surgery showed that there was no absorption of alcohol across the internal bladder lining. Of 52 patients, who had to undergo transurethral prostatic resection, 23 had positive breath alcohol values of up to 0.81/1000. In 6 patients the blood alcohol levels only were elevated (max. 0.18/1000). In 23 other patients no increased blood or breath alcohol levels were detectable. The negative breath alcohol levels in 6 patients were most probably attributable to low breath volumes due to lack of cooperation caused by pre- and/or intraoperative sedation. There were no significant changes in central venous pressure, mean arterial pressure or heart rate even at the time of maximal alcohol levels, compared with initial values. These parameters thus cannot be used for the early recognition of beginning absorption. Simultaneous monitoring of serum sodium concentrations revealed significant decreases at the time of maximal breath alcohol levels. Yet, the first indication of beginning absorption was always a positive alcohol level. Serum sodium changes followed later with increasing alcohol levels. Sodium concentration did not drop before a positive alcohol level was measured in any of these cases. CONCLUSION. It was thus proven that the addition of ethanol to the irrigating fluid and monitoring of the patient's exhaled breath with the Alco-testmonitor is a simple, non-invasive system that can be routinely used for early detection of absorption during transurethral prostatic resection. Adequate adjustment of the further course of the operation was possible. The dreaded TUR syndrome did not develop in any of the patients monitored in this way.     

Sorbitol concentrations in plasma in connection with transurethral resection of the prostate using sorbitol solution as an irrigating fluid

20 patients undergoing transurethral resection of the prostate (TURP) using 5% sorbitol (N = 13) or Cytosol (N = 7) (5% sorbitol and 0.25% acetic acid) as an irrigating fluid were studied. The sorbitol concentration was determined in serum (plasma), as were sodium, prostatic acid phosphatase protein (PAP) and osmolality, as possible indicators of absorption of irrigating fluid. The plasma level of sorbitol immediately postoperatively, the increase in serum PAP and the decrease in serum sodium all reflect the amount of irrigating fluid absorbed during TURP. The three variables are intercorrelated. The plasma osmolality was not significantly changed. The maximum sorbitol concentration immediately postoperatively in any patient was 6.0 g/l (33.5 mmol/l). The mean for the series was 1.2 g/l (6.8 mmol/l). The mean serum PAP increase was 31 micrograms/l. The serum sodium decrease ranged between 0 and 14 mmol/l, mean 5.0 mmol/l. The mean half-life of sorbitol in plasma was short: 35 min, reflecting rapid metabolism. An estimate of the volume of fluid absorbed was made from the plasma sorbitol levels observed. A fluid absorption up to 2.3 l (mean 0.6 l) was found. A marked diuretic effect up to 14.1 ml/min (mean 7.8 ml/min) was observed in some cases when irrigation with sorbitol was combined with intravenous furosemide given postoperatively.     

Mannitol concentrations in blood plasma in connection with transurethral resection of the prostate using mannitol solution as an irrigating fluid

Thirteen patients undergoing transurethral resections of the prostate (TURP) using iso-osmolar 5% mannitol as an irrigating fluid were studied. Mannitol was determined in serum (plasma), as were sodium, prostatic acid phosphatase protein (PAP) and osmolality as probable indicators of absorption of irrigating fluid. The plasma level of mannitol (mean 2.7 g/l = 15 mmol/l) immediately postoperatively, the increase in serum PAP (mean 93 micrograms/l) and the decrease in serum sodium (mean 8.7 mmol/l) all reflect the amount of irrigating fluid absorbed during TURP. The three variables are intercorrelated. The plasma osmolality was unchanged (mean -1 mosmol/kg). A small but constant fraction of mannitol was found in the erythrocytes 2 hours after the operation, amounting to about 3% of the simultaneous plasma concentration. The mean plasma half-life of mannitol was 127 min in the absence of uraemia. In two cases showing a slight increase in serum creatinine the half-lives were prolonged. An estimate of the volume of fluid absorbed was made from the observed plasma mannitol levels. A fluid absorption of up to 3 litres (mean 1.1 l) was found. A strong diuretic effect was observed in some cases when irrigation with mannitol was combined with i.v. furosemide. We conclude that the i.v. diuretic should be withheld until the extent of fluid absorption has been estimated. If the sodium concentration in the serum is largely unchanged immediately postoperatively, diuresis can be induced by an intravenous diuretic.     

Blood ammonia concentrations resulting from absorption of irrigating fluid containing glycine and ethanol during transurethral resection of the prostate

In 30 patients the blood ammonia concentration was measured 30 min was after transurethral resection of the prostate during which absorption of irrigating fluid containing 1.5% of glycine and 1% of ethanol had been indicated by serial expired breath tests. The volume of irrigating fluid that had been absorbed was either measured volumetrically (n = 25) or estimated from the ethanol concentration in the expired breath (n = 5); the median volume of irrigating fluid absorbed was 1.3 litres (range 0.2-4.3). There was no consistent rise in the blood ammonia concentration, nor was there any correlation between the blood ammonia concentration and the volume of irrigating fluid absorbed. No patient developed symptoms that could be clearly related to hyperammonaemic glycine toxicity, but 18 of the 30 patients developed other signs of the "TURP syndrome". The present results suggest that irrigating fluid containing both glycine and ethanol does not significantly increase blood ammonia concentration or produce symptoms of glycine toxicity.     

1％乙醇标记法连续定量监测TURP术灌洗液吸收的初步研究

目的　用 1%乙醇标记经尿道前列腺切除 (TURP)术灌洗液 ,研究呼出气乙醇浓度与血管内吸收量的关系。方法　 2 5例TURP术患者 ,3%甘露醇膀胱灌洗液加乙醇 (终浓度 1% ) ,采用偶联酶法和Evan氏蓝染料稀释法测定呼出气乙醇浓度和血浆容量 ,以血浆容量变化值估计血管内吸收量 ,分析吸收量与呼出气乙醇浓度的相关性。结果　吸收量与呼出气乙醇浓度明显相关 (r =0 842 ,P <0 0 1) ,回归方程R2 =0 90 2 ,P <0 0 0 1;将冲洗时间加入多元分析 ,回归方程R2 =0 92 7,P <0 0 0 1。结论　乙醇标记监测法安全、简便、无创、无污染 ,与灌洗液吸收入血量相关性好 ,考虑时间因素的多元回归方程可用于临床定量监测TURP术灌洗液吸收。     

Total fluid balance during transurethral resection of the prostate

All fluids given and recovered during and for 24 hours following transurethral resections of the prostate (TURP) in 35 elderly men were recorded and compared with the health status of the patient. The results show that irrigating fluid absorption and the choice of a crystalloid or a colloid solution for intravenous fluid supplementation were the most important factors governing the total fluid balance at the end of TURP as well as 2 hours later. At 24 hours after the operation, the absorption of irrigating fluid during TURP and the presence of cardiac disease promoted retention of fluid. Impaired kidney function and serum cortisol concentration did not, however, correlate with the fluid balance.     

Absence of lactate accumulation on transurethral resection of the prostate using 2.5% sorbitol solution as an irrigating fluid

19 patients with benign hyperplasia of the prostate were studied. During transurethral resection of the prostate, 2.5% sorbitol solution was used as an irrigating fluid. Blood samples were taken preoperatively, immediately postoperatively, and 60 and 120 min postoperatively. Samples were analysed for sorbitol metabolites (fructose, glucose, lactate and pyruvate) and inorganic phosphate. The series was divided into two groups, one with low absorption and one with high absorption of irrigating fluid. The limit for the plasma sorbitol concentration immediately postoperatively, dividing the groups, was 1.0 mmol/l, corresponding to an absorbed fluid volume of about 0.1 l. There was a slight increase in lactate and a significant decrease in pyruvate in the blood in both groups postoperatively. Blood fructose was zero in the group with low absorption of irrigating fluid whereas there was a slight increase in the group with high absorption, with a maximum of 0.53 mmol fructose/l. Blood glucose did not show any significant changes postoperatively. Inorganic phosphate in serum showed a significant decrease postoperatively in both groups. There were no significant differences between the groups at the various postoperative sampling times with regard to lactate, pyruvate, glucose or inorganic phosphate in the blood. Thus, we did not observe any accumulation of lactate in the blood when using 2.5% sorbitol solution as an irrigating fluid with absorbed fluid volumes up to 1 litre (corresponding to 25 g sorbitol).     

Hypertonic saline for intraoperative fluid therapy in transurethral resection of the prostate

We tested hypertonic saline solution (HS) to determine its effectiveness in surgical procedures for prostatic hypertrophy. We randomly selected 40 patients undergoing elective transurethral resection of the prostate for either infusion of HS (3% NaCl) at 4ml·kg⁻¹·min⁻¹ (HS group) or lactated Ringer's solution (LR) at 8 ml·kg⁻¹·min⁻¹ (LR group). Anesthesiologists regulated the intraoperative infusion rate as needed to maintain blood pressure. There were no differences in systolic blood pressure, heart rate, central venous pressure, or arterial blood oxygenation between the two groups. In the HS group, plasma sodium, chloride, and osmolality, measured in the recovery room, were significantly increased; however, they returned to preanesthetic levels the day after surgery. In the LR group, in contrast, plasma sodium decreased significantly and this lower value persisted for 1 day. An osmolar gap exceeding 10mOsm·kg⁻¹ was observed in 2 patients in the HS group, but plasma sodium remained at normal values. However, in the 1 patient in the LR group whose osmolar gap exceeded 10mOsm·kg⁻¹, plasma sodium was 115 mEq·I⁻¹. HS, at a low dose, is useful in the intraoperative management of transurethral resection of the prostate.     

Various methods of determining irrigating fluid absorption during transurethal resection of the prostate

Summary A review is presented of all methods, nonquantitative as well as quantitative, applied in the determination of absorption of irrigating fluids used during transurethral resection of the prostate. The nonquantitative methods are clinical observations of pulmonary edema, cerebral edema, cardiac failure, mental agitation, hypertension, hemolysis, large postoperative diuresis, unexplained decrease in hematocrit, transient bacteremia, osteomyelitis, hyperglycemia, and extravasation of contrast medium. To determine total absorption in clinical practice the volumetric or gravimetric methods are the most reliable. The use of radioindicators added to the irrigation fluid is recommended for discrimination between intravascular and extravascular absorption. For this purpose 131 I-macroaggregated human serum albumin has the most advantages: low radiation hazard with good sensitivity, possibility of quantitative external monitoring of intravascular absorption, short time delay of the activity accumulation, and additional quantitative measurement of extravascular absorption.This work was supported in part by the Deutsche Forschungsgemeinschaft.     

Plasma haemoglobin concentrations and other influx variables in blood in connection with transurethral resection of the prostate using distilled water as an irrigating fluid

Eight patients undergoing transurethral resection of the prostate (TURP) using sterile distilled water as an irrigating fluid were studied. The concentrations of plasma haemoglobin, serum sodium, serum prostatic acid phosphatase protein (PAP) and plasma osmolality were determined as possible indicators of absorption of irrigating fluid. In 3 patients there was a marked increase in plasma haemoglobin immediately postoperatively with a maximum of 3.3 g haemoglobin/l plasma. In the remaining 5 patients the plasma haemoglobin level did not exceed 0.7 g/l immediately postoperatively. In all cases there was a fairly rapid return of the elevated plasma haemoglobin level to preoperative values. There was also a postoperative increase in the serum PAP level which was not correlated with the simultaneous increase in plasma haemoglobin concentration. There was no significant change in the sodium, potassium or albumin concentration in serum nor in plasma osmolality postoperatively. There was some decrease in the postoperative serum creatinine and uric acid levels. The preoperative serum creatinine concentration was within reference limits in 7 patients and borderline high in 1 patient. The haemoglobin binding plasma protein haptoglobin showed a slight non-significant increase immediately postoperatively and a significant decrease in concentration 2 hours postoperatively. The mean plasma haemoglobin concentration immediately postoperatively did not exceed the mean preoperative haemoglobin binding capacity of serum. The mean preoperative haemoglobin binding capacity was 1.2 g/l and the mean plasma haemoglobin level was 1.2 g/l immediately postoperatively. Two hours later the mean plasma haemoglobin level was 0.8 g/l. The mean serum haptoglobin concentration was 2.4 g/l preoperatively, 2.6 g/l immediately postoperatively and 2.0 g/l 2 hours later.(ABSTRACT TRUNCATED AT 250 WORDS)     

Monitoring of irrigating fluid absorption during transurethral prostatectomy

A simple, reliable method to detect absorption of irrigating fluid during transurethral prostatectomy is to tag irrigating fluids with 1% ethanol and monitor expired breath ethanol concentrations. This method correlated well (n = 0.79) with other existing methods of absorption monitoring in 20 anaesthetised patients. Ethanol (1%) tagging does not alter the optical quality of the irrigating fluid and is harmless to the patient. The technique is non-invasive, repeatable, cheap and gives instant results. It can be used in anaesthetised or awake patients and can detect absorption of as little as 100-150 ml in any 10-minute period.