Visual disturbances, serum glycine levels and transurethral resection of the prostate

Transient visual disturbances have been noted in patients undergoing transurethral resection of the prostate. It has been suggested recently that these visual aberrations were secondary to high serum concentrations of glycine from the intravasation of irrigant solutions used during the procedure. We prospectively studied visual acuity, serum electrolytes, glucose, ammonia and glycine concentrations in 18 patients undergoing transurethral resection of the prostate. Of our patient population 22% experienced significant decreases in visual acuity. We found that all patients had significantly elevated serum glycine concentrations but that there was no correlation of visual symptomatology with serum electrolyte or glucose concentrations. Our data further suggest that impeded metabolism of glycine may be more important than the absolute serum concentration in symptomatic patients.     

The effect of the choice of irrigation fluid on cardiac stress during transurethral resection of the prostate: a comparison between 1.5% glycine and 5% glucose

PURPOSE: Variable amounts of irrigation fluid are absorbed during transurethral prostate resection. Previous studies suggest that cardiac stress occurs as a result of transurethral prostate resection, possibly due to glycine absorption. We performed a prospective, blinded, randomized trial comparing 1.5% glycine with 5% glucose irrigating solution. We assessed whether glycine or glucose irrigation for transurethral prostate resection is associated with cardiotoxicity, as measured by troponin I and echocardiogram changes. MATERIALS AND METHODS: Between December 2001 and March 2003, 250 patients were recruited. Changes in immediate postoperative vs preoperative echocardiogram and serum cardiac troponin I indicated perioperative myocardial stress. Intraoperative irrigating fluid absorption was measured with 1% ethanol as a marker. Operative details recorded were anesthesia type, resection time, resected tissue weight and temperature change. Blood loss was measured with transfusions considered. Postoperatively blood assessments included serum glycine assay. RESULTS: Five patients (4%) in the glycine group and 3 (2%) in the glucose group had significantly increased troponin I after surgery. Of these men 1 per group had myocardial infarction and the remainder had transient ischemia. Logistic regression was used to identify factors associated with an unfavorable outcome, which was recorded as a significant increase in troponin I or ischemic changes on echocardiography. Increasing patient age and blood loss were associated with an unfavorable outcome (OR 1.84 and 1.24, respectively). We noted no significant differences in the 1.5% glycine and 5% glucose groups with regard to troponin I/echocardiogram. However, when the glycine assay was compared with adverse outcomes, an increased glycine assay was found to be associated with echocardiogram changes (p = 0.001) and with increased troponin I levels (relative risk 10.71). CONCLUSIONS: Transurethral prostate resection has an effect on the myocardium perioperatively. Glycine absorption causes echocardiogram changes and it is associated with increased troponin I. Increasing patient age and blood loss are associated with myocardial insult. The risk of increased blood loss was accumulative with each unit lost. Unrecognized blood loss or glycine absorption may explain the increase in morbidity and mortality previously reported in patients who undergo transurethral prostate resection.     

Independent plasma levels of sodium and glycine during transurethral resection of the prostate

This study was done to evaluate the potential role of plasma glycine levels as an indicator of the biochemical changes occurring during or shortly after transurethral resection of the prostate (TURP). Seventeen patients undergoing TURP were studied to determine the fate of the absorbed glycine and its effects on other amino acids and their relationship to changes in serum sodium and osmolarity. Twelve patients showed more than 100 per cent increase in plasma glycine levels with values ranging to more than 100-fold elevation. Only two patients showed a change in serum sodium of greater than 10mEqll with corresponding change in osmolarity. In one such patient there was no accompanying change in plasma glycine. Thus, major changes in plasma glycine and serum sodium may occur independently of one another, and may separately account for manifestations of the reactions following TURP.     

Morbidity of radical perineal prostatectomy following transurethral resection of the prostate

Radical prostatectomy in patients who have had prior transurethral resection of the prostate has been reported to result in significant morbidity. From 1974 to 1982, 30 patients who had had previous transurethral resection of the prostate underwent radical perineal prostatectomy for localized prostatic cancer. Operative time and blood loss were similar to a group of patients who had not had prior transurethral resection of the prostate. Over-all, 3 patients (10 per cent) had total incontinence and 3 (10 per cent) had stress incontinence requiring a pad or device. No patient undergoing radical prostatectomy less than 4 weeks or more than 4 months after transurethral resection of the prostate had postoperative incontinence. When radical perineal prostatectomy was performed between 4 weeks and 4 months after transurethral resection of the prostate the incidence of incontinence was 50 per cent. Five patients experienced prolonged perineal urinary drainage, all but 1 of whom healed spontaneously. Of the 6 patients with incontinence 3 had prolonged drainage. No patient had a rectal injury and there was no operative mortality. Two patients died without cancer and 1 has evidence of disease recurrence. We conclude that radical prostatectomy may be performed safely with acceptable morbidity following transurethral resection of the prostate and that if 4 weeks has elapsed since resection it might be advantageous to wait 4 months before performing radical surgery to lessen the risk of incontinence.     

Resorption of the lavage fluid during transurethral resection of the prostate. Apropos of 13 cases

The authors report on thirteen patients who developed a variety of symptoms after transurethral resection of the prostate; confusion, seizures, blurred vision with mydriasis, nausea and vomiting, bradycardia, and hypotension. This post-resection syndrome is caused by resorption of a large amount of the hypotonic solution used during the surgical procedure and containing 1.5% glycine. Postoperative sodium levels were assayed in all patients and consistently found to be low (105 to 124 mEq/l). Serum glycine was measured in three patients and the very high levels found suggest that absorption of glycine during transurethral resection of the prostate may contribute to the symptoms of encephalopathy.     

Transient blindness following transurethral resection of the prostate in an achondroplastic dwarf

Neurological complications associated with transurethral resection of the prostate have been reported in the past. We report on an achondroplastic dwarf who suffered transient blindness following transurethral resection of the prostate. The blindness correlated with a markedly elevated serum glycine level of 13,734 mumol. per l. We discuss the possibility of glycine being responsible for this complication.     

Blood ammonia levels after intravenous infusion of glycine solution with and without ethanol.

OBJECTIVE: Absorption of glycine 1.5% during transurethral resection of the prostate may increase blood ammonia levels, but hyperammonaemia has not been described when the fluid also contained ethanol 1%. The aim of this experimental study was to evaluate whether ethanol 1% reduces glycine-induced hyperammonaemia. MATERIAL AND METHODS: Two intravenous infusions of glycine solution with and without ethanol 1% added were given on different occasions to 20 male volunteers (mean age 30 years). Half of them received 22 g of glycine over 50 min and the others approximately 18 g over 30 min. Blood ammonia was measured before and 30 min after the infusion. The serum levels of free amino acids were measured on 7 occasions during 10 of the experiments. RESULTS: The glycine infusions increased blood ammonia levels from 37 micromol/l (median, 10th and 90th percentile limits 34-53) to 57 micromol/l (27-110; p < 0.001). The change was greater after the larger glycine dose, regardless of whether the fluid contained ethanol (p < 0.05). The only amino acid concentration correlating with blood ammonia was glycine, which showed higher levels in those who had a rise in blood ammonia of 50% or more. CONCLUSIONS: Ethanol 1% did not reduce the increase in blood ammonia concentration after the administration of glycine solution.     

Endocrine therapy for bladder outlet obstruction from carcinoma of the prostate

The optimum treatment of bladder outlet obstruction from prostatic cancer is controversial. Although transurethral resection of the prostate may provide immediate relief of the obstruction, there are attendant surgical and anesthetic risks, as well as accumulating clinical evidence to suggest that transurethral resection of the prostate may cause tumor dissemination and diminish patient survival. Orchiectomy, which can be performed safely with local anesthesia, provides definitive endocrine therapy and has been used at our institution in preference to transurethral resection to relieve bladder outlet obstruction from carcinoma of the prostate. There were 35 patients between 51 and 96 years old in urinary retention from carcinoma of the prostate. Patients were treated with orchiectomy and suprapubic or urethral catheter drainage, and subsequently were given voiding trials. If a patient failed to void satisfactorily within 60 days transurethral resection of the prostate was performed. Over-all, 24 of 35 patients (68.6 per cent) were relieved of bladder outlet obstruction by orchiectomy alone. Neither tumor stage nor grade correlated significantly with the response to orchiectomy. We conclude that transurethral resection of the prostate may be held in reserve for patients who do not respond to endocrine therapy or those who do not wish to risk sexual impotence.     

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.     

Antibiotic prophylaxis of urinary tract infection after transurethral resection of the prostate: a randomized study

Transurethral resection of the prostate is associated with a major risk of postoperative infection. To evaluate the clinical and bacteriological efficacy of antibiotic prophylaxis with a single dose of netilmicin sulfate, we conducted a randomized study in 100 patients with sterile preoperative urine undergoing transurethral resection of the prostate. Of these patients 95 were evaluated: 47 were randomized to the control group and received an intramuscular injection of 1.5 ml. of a 0.9 per cent solution of sodium chloride 1 hour preoperatively and 48 were given an intramuscular injection of 150 mg. netilmicin sulfate in a volume of 1.5 ml. 1 hour preoperatively. Of the patients 16 in the control group (34 per cent) and only 1 in the treated group (2 per cent) had bacteriuria (greater than 10(5) bacteria per ml.) (p less than 0.001). This difference also was significant 2 and 5 days postoperatively (p less than 0.05 and p less than 0.001, respectively). One patient in the control group had bacteremia compared to none in the treated group. Clinical signs of infection were less common in the treated group. Sensitivity studies revealed that all of the organisms tested were sensitive to netilmicin sulfate. High concentrations of netilmicin sulfate were found in the urine collected at operation (162 +/- 112 micrograms per ml. urine).     

Visual evoked potentials and visual acuity after transurethral resection of the prostate

Changes in visual evoked potentials, visual acuity, blood ammonia levels and serum electrolytes (Na+ and K+) after transurethral resection of the prostate using glycine as an irrigating fluid performed under subarachnoid block were studied in 12 patients, in the pre-operative and immediate postoperative periods. Visual evoked potentials (p100 latency), recorded by shift of a checkerboard pattern, increased significantly from a pre-operative value of mean (SEM) 101.18 (1.63) msec in the right eye, and 102.5 (1.47) msec in the left eye to 108.91 (1.8) msec (p less than 0.01) and 108.08 (2.53) msec (p less than 0.01) respectively in the postoperative phase. There were no changes in visual acuity as assessed by a Snellen's chart, blood ammonia levels and serum electrolyte concentrations. The amount of glycine used intra-operatively for irrigation ranged from 3 to 31 litres.     

A COMPARISON OF 1.5% GLYCINE AND 2.7% SORBITOL-0.5% MANNITOL IRRIGANTS DURING TRANSURETHRAL PROSTATE RESECTION

PURPOSE: We performed a prospective randomized trial comparing glycine 1.5% with 2.7% sorbitol-0.5% mannitol irrigating solution. We evaluated blood loss, fluid absorption, temperature change, cardiac effects and postoperative symptoms. MATERIALS AND METHODS: Between April 1998 and July 1999, 205 treated patients were included in the statistical analysis. Intraoperative irrigating fluid absorption was measured with the patient on the operating table. Serum cardiac troponin I was used as a marker of perioperative myocardial damage. Operative details were recorded, including the type of anesthesia, resection time and the weight of resected tissue. Postoperative symptoms were documented prospectively. RESULTS: Mean patient age was not significantly different in the glycine and sorbitol-mannitol groups. (72.1 versus 73.7 years). American Society of Anesthesiologists grade was also comparable. Median resection time was 27 minutes and resected tissue weighed a mean of 21 gm. The median resection rate was 0.8 gm. per minute. Blood loss and temperature changes during resection were similar in the 2 groups. Overall median blood loss was 216 ml. and irrigant absorption was 140 ml. In the sorbitol-mannitol group significantly less fluid was apparently absorbed during resection (median 88.2 versus 184.4 ml.). Analysis of the incidence of symptoms of the transurethral prostate resection syndrome did not show any differences in the irrigant groups. Cardiac damage measured using troponin I also showed no significant difference in the 2 groups, although there was a high overall incidence of 7.5%. CONCLUSIONS: We noted no significant differences in 1.5% glycine and 2.7% sorbitol-0.5% mannitol as an irrigating solution for transurethral prostate resection.     

Serum ammonia levels in response to glycine infusion in normal and cirrhotic rats

Elevated serum ammonia may play a role in central nervous system derangement after transurethral resection of the prostate. Glycine used as a surgical irrigant for prostate resection produces ammonia as a by-product after liver and renal metabolism. The presence of liver dysfunction often leads to an inability to remove generated ammonia from the circulation. To determine whether the presence of cirrhosis allows significant metabolism of glycine and the resulting serum ammonia levels generated, the production of ammonia after glycine infusion was examined in normal and cirrhotic rats. Hepatic microsomal enzyme induction was produced in male Sprague-Dawley rats given sodium phenobarbital, added to the drinking water to hasten the development of cirrhosis, by increasing the toxicity of carbon tetrachloride given intragastrically to one group at weekly intervals for production of cirrhosis. A control group was maintained under similar conditions except for carbon tetrachloride dosing. The end point for production of cirrhosis was the development of ascites. Two weeks after the development of ascites in the cirrhotic rats and the discontinuation of phenobarbital in both groups, both control and cirrhotic rats were anesthetized with IP pentobarbital and glycine (1.25 g/kg; 7.5%) was given intravenously. Venous blood samples were taken at intervals up to 120 min for serum ammonia analysis. After the final serum ammonia sample, lethal pentobarbital injection was given and livers and kidneys removed for histologic analysis. Terminal body weight, glycine dose, and renal histology were not different between groups. Liver weights were greater in cirrhotic rats.Baseline serum ammonia levels were also greater int he cirrhotic rats.(ABSTRACT TRUNCATED AT 250 WORDS)     

Osmotic and metabolic sequelae of volumetric overload in relation to the TUR syndrome

In an attempt to understand the pathophysiology of the transurethral resection syndrome this prospective metabolic study was conducted on 100 consecutive patients undergoing transurethral resection of the prostate (TURP). The volume of glycine absorbed, intravenous fluid given and blood loss were calculated, and serum osmolality, sodium and glycine were measured before, during and after operation. The mean volume of glycine absorbed, fluid gain and blood loss were 0.6, 1.57 and 0.356 litres respectively. The mean weight of prostate resected was 30.8 g and resection time was 56.5 min. The mean serum osmolality dropped from 291 to 286 mOsm/l, sodium dropped from 138 to 132 mmol/l and glycine concentration increased from 293 to 3599 mumol/l post-operatively. Ten patients developed signs suggestive of the TURP syndrome. Multiple regression analysis showed that the most consistent statistically significant factors in relation to the syndrome were volumetric gain and hypo-osmolality. The latter proved to be the only significant factor later post-operatively. The increase in serum glycine and drop in serum sodium concentrations were the best serological markers, reaching significance only after excluding volumetric gain and osmolality from the analysis.     

Amino acid concentrations in plasma and skeletal muscle after transurethral resection syndrome.

The concentrations of amino acids in plasma and skeletal muscle were measured 1 and 4 hours after transurethral prostatic resection in three patients who developed symptoms of the transurethral resection syndrome. The irrigating solution contained 1.5% of glycine and 1% of ethanol. The concentrations of glycine in plasma and muscle were equal within an hour of the operation, and at four hours the abnormally high glycine concentration persisted in muscle, though it had decreased rapidly in plasma. Our data suggest that skeletal muscle is a quantitatively important reservoir for glycine when this amino acid is supplied in potentially toxic amounts, but that the plasma glycine concentration returns to normal as the patient's clinical condition improves.     

Bipolar transurethral resection in saline--an alternative surgical treatment for bladder outlet obstruction?

PURPOSE: The transurethral resection in saline system uses bipolar energy for transurethral prostate resection, thus, avoiding the need for glycine irrigation and its associated complications. We compared the clinical efficacy and safety of bipolar transurethral resection in saline and of monopolar transurethral prostate resection for symptomatic benign prostate hyperplasia. MATERIALS AND METHODS: From January 2005 to June 2006, 238 consecutive patients with symptomatic benign prostate hyperplasia were randomized into a prospective, controlled trial comparing the 2 treatment modalities. Patient demographics, operative time, hospital stay and complications were noted. Serum hemoglobin and electrolytes were determined in all patients immediately before and after the endoscopic procedure. RESULTS: During 18 months 120 patients were randomized to the conventional transurethral prostate resection group and 118 were randomized to the transurethral resection in saline group. Patient profiles, weight of resected prostatic tissue and duration of hospitalization were similar in the 2 groups. The decrease in serum sodium and serum chloride was statistically significantly greater in the transurethral prostate resection group than in the transurethral resection in saline group (each p = 0.05). The transurethral resection in saline procedure required significantly more time (mean 56 vs 44 minutes, p <0.01). There was 1 case (0.8%) of transurethral resection syndrome in the transurethral prostate resection group but none in the transurethral resection in saline group. Postoperative bleeding did not significantly differ between the 2 groups. Clot retention was observed in 6 (5%) and 4 patients (3%) in the transurethral prostate resection and transurethral resection in saline group, respectively. Two repeat interventions were required in the transurethral prostate resection group. CONCLUSIONS: The bipolar transurethral resection in saline system is as efficacious as monopolar transurethral prostate resection but it is safer than the latter because of the lesser decrease in postoperative hypernatremia and the smaller risk of transurethral resection syndrome. However, probably due to technical reasons, transurethral resection in saline operative time is significantly longer.     

Seminal vesicle tissue in "resectate" of transurethral resection of prostate

We reviewed the histologic specimens from 123 consecutive patients undergoing transurethral resection of the prostate to determine the presence of seminal vesicle tissue. Additionally, relevant patient data were collected from the records, and a questionnaire regarding pre- and postoperative sexual function was given. The incidence of seminal vesicle tissue in the resectate was 23 per cent. No significant morbidity such as acute epididymitis or impairment of sexual function was associated with the occurrence of seminal vesicle tissue in the specimens. Consequently, no prophylactic measures seem indicated in patients undergoing partial resection of the seminal vesicles in connection with transurethral resection of the prostate.     

The role of ammonia toxicity in the post transurethral prostatectomy syndrome

To investigate the aetiology of altered mental status following transurethral prostatectomy (TURP), serum electrolyte and blood ammonia levels were measured in 33 patients before and immediately after TURP. The irrigating fluid was 3% sorbitol in 12 patients and 1.5% glycine in 21. Serum electrolyte changes were similar in both groups. Elevated blood ammonia levels were observed in eight of the 21 patients receiving glycine irrigation. Three of these eight patients demonstrated clinical signs of encephalopathy. Absorption of glycine during transurethral prostatectomy appears to produce hyerammonaemia in some patients and may contribute to the encephalopathy.     

No evidence of fluid absorption during continuous low-pressure transurethral resection of the prostate: assessment by measuring expiratory breath ethanol concentrations.

OBJECTIVE: Measurement of the ethanol concentration in expired breath during transurethral resection of the prostate (TURP). METHODS: TURP is a noninvasive method to estimate the amount of irrigant absorbed. The expiratory breath ethanol concentrations (EBEC) were measured with a standard alcohol breath analyzer in 35 patients in the course of TURP. All interventions were performed with a 27-french continuous flow resectoscope using a solution of 1. 5% glycine + 1% ethanol as irrigating fluid. Serum sodium and osmolality were measured pre- and postoperatively. No patient developed signs of transurethral resection syndrome; no significant changes in serum sodium, osmolality and EBEC were found throughout the operation. CONCLUSION: Absorption of irrigant fluid during TURP with continuous low-pressure irrigation seems to be extremely slight (if not absent) as measured by expired breath ethanol method.     

Prevention of post-prostatectomy vesical neck contracture by prophylactic vesical neck incision

Most vesical neck contractures occur after resection of adenomas weighing less than 20 gm. This complication is believed to be secondary to excessive resection or fulguration of an undilated bladder neck. Prophylactic bladder neck incision was performed in conjunction with transurethral resection of the prostate on 114 patients with prostatic adenomas weighing less than 20 gm. Vesical neck contracture occurred in 1 patient (0.87 per cent), compared to 12 contractures in 161 patients who underwent transurethral resection of the prostate alone (7.5 per cent). Increasing bladder neck diameter by incision appears to be protective against formation of vesical neck contractures in patients with small obstructing prostatic adenomas.