Intrarectal lidocaine during transrectal prostate biopsy: results of a prospective double-blind randomized trial

PURPOSE

Recent reports have indicated the benefit of anesthesia during prostate biopsy. To assess this finding objectively we performed a prospective randomized double-blind study to compare patient pain with and without local anesthesia during transrectal ultrasound guided prostate biopsies.

MATERIALS AND METHODS

Between August 2000 and March 2001, 108 men undergoing transrectal ultrasound guided biopsy of the prostate were randomized in double-blind fashion to receive intrarectal 2% lidocaine gel or intrarectal lubricant alone. No patient received pre-procedure narcotics or sedation. Pain associated with biopsy was determined using a horizontal linear visual analog pain scale. Pain scores in the 2 treatment groups were compared and possible predictors of increased pain were examined.

RESULTS

The 2 groups were similar in demographic characteristics. There was no significant difference in pain score in the 2% lidocaine and lubricant alone groups (28.3 versus 28.9 mm., p = 0.88). Previous biopsy, time since previous biopsy, physician, number of biopsies and prostate volume did not correlate with pain score, while age correlated negatively with the score (r = -0.27, p = 0.005). A single complication involving a vasovagal episode resolved spontaneously.

CONCLUSIONS

Intrarectal lidocaine gel provides no significant therapeutic or analgesic benefit compared with lubricant alone for transrectal ultrasound guided biopsy of the prostate. In younger patients more discomfort is associated with this procedure.

Radical cystectomy is safe in elderly patients at high risk

PURPOSE

Radical cystectomy is standard treatment for bladder cancer in healthy individuals. We determined the safety of radical cystectomy in elderly patients at high risk.

MATERIALS AND METHODS

We reviewed the records of all patients who underwent radical cystectomy at our institution between January 1994 and June 2000. Of these 382 patients we identified 44 who were elderly and at high risk, as defined by age 75 years or greater and American Society of Anesthesiologists classification 3 or greater. We examined postoperative care, perioperative minor/major complications, the mortality rate and the need for rehospitalization.

RESULTS

Median age of the 44 patients was 77.5 years (range 75 to 87). American Society of Anesthesiologists class was 3 in 40 patients and 4 in 4. Median hospitalization was 7 days (range 4 to 20). Postoperatively 31 of the 44 patients (70%) were transferred directly to the general urology floor, while cardiac monitoring was required postoperatively in 30%. Nine of these patients were transferred to a step-down unit and the remaining 4 required surgical intensive care unit admission. Minor and major complications developed in 10 (22.7%) and 2 (4.5%) cases, respectively. No patients died in the perioperative period and 4 patients were hospitalized within 6 months of discharge home.

CONCLUSIONS

Our results support the safety of radical cystectomy in elderly patients at high risk. Acceptable perioperative morbidity and mortality may be achieved without routine intensive monitoring postoperatively.

Does the cleaning technique influence the durability of the <9F flexible ureteroscope?

BACKGROUND AND PURPOSE

The fragility of the <9F flexible ureteroscope limits its availability to general urology practice. The purpose of this study was to determine whether the technique used to clean the flexible ureteroscope or the number of persons handling the instrument during the cleaning process influenced endoscope breakage or deterioration during regular endourologic use.

PATIENTS AND METHODS

A new Olympus URF/P3 flexible 7.5F ureteroscope was used for each of two 30-day study periods during which a single surgeon used the endoscope for a variety of upper urinary tract procedures. During the first 30-day period (Group 1), the endoscope was leak-proof-pressure tested and cleaned by the endourology support team using the Steris 20 (peroxyacetic acid 35%) technique. During the second 30-day period (Group 2), the endoscope was leak-proof tested and cleaned only by the surgeon using the Cidex (glutaraldehyde 2.4%) technique. A record was kept for each ureteroscopic case to document the patient position, access technique, time the endoscope was in the urinary tract, instruments passed through the ureteroscope, and the maximum irrigant pressure used. In addition, a record was made of the number of broken fibers, the degree of flexion and deflexion of the endoscope, and the problems encountered with the endoscope during the case.

RESULTS

The two study groups were similar in terms of the total number of cases performed, the mean time the endoscope was in the urinary tract per case, the access approach used, and the use of the ureteral access sheath and ancillary equipment. In Group 2, the endoscope was used for a longer total time (618 minutes v 457 minutes), and access to a lower pole calix was more than twice as common as in Group 1. This may explain why more broken fibers were noted in the instrument used in Group 2 over the study period (eight v four broken fibers) than in Group 1. The only breakage occurred as a result of the surgeon accidentally activating the laser probe inside the working channel of the endoscope in Group 2.

CONCLUSION

The technique and number of personnel involved in the maintenance and cleaning of the flexible ureteroscope does not have a significant effect on the durability and function of these instruments. It is the arduous demands of the endourologic procedure that influence the durability of these fragile endoscopes.

Time course and mechanism of myocardial catecholamine release during transient ischemia in vivo

BACKGROUND

Elevated concentrations of norepinephrine (NE) have been observed in ischemic myocardium. We investigated the magnitude and mechanism of catecholamine release in the myocardial interstitial fluid (MIF) during ischemia and reperfusion in vivo through the use of microdialysis.

METHODS AND RESULTS

In 9 anesthetized pigs, interstitial catecholamine concentrations were measured in the perfusion areas of the left anterior descending coronary artery (LAD) and the left circumflex coronary artery. After stabilization, the LAD was occluded for 60 minutes and reperfused for 150 minutes. During the final 30 minutes, tyramine (154 nmol. kg(-1). min(-1)) was infused into the LAD. During LAD occlusion, MIF NE concentrations in the ischemic region increased progressively from 1. 0+/-0.1 to 524+/-125 nmol/L. MIF concentrations of dopamine and epinephrine rose from 0.4+/-0.1 to 43.9+/-9.5 nmol/L and from <0.2 (detection limit) to 4.7+/-0.7 nmol/L, respectively. Local uptake-1 blockade attenuated release of all 3 catecholamines by >50%. During reperfusion, MIF catecholamine concentrations returned to baseline within 120 minutes. At that time, the tyramine-induced NE release was similar to that seen in nonischemic control animals despite massive infarction. Arterial and MIF catecholamine concentrations in the left circumflex coronary artery region remained unchanged.

CONCLUSIONS

Myocardial ischemia is associated with a pronounced increase of MIF catecholamines, which is at least in part mediated by a reversed neuronal reuptake mechanism. The increase of MIF epinephrine implies a (probably neuronal) cardiac source, whereas the preserved catecholamine response to tyramine in postischemic necrotic myocardium indicates functional integrity of sympathetic nerve terminals.

Catecholamine handling in the porcine heart: a microdialysis approach

Experimental findings suggest a pronounced concentration gradient of norepinephrine (NE) between the intravascular and interstitial compartments of the heart, compatible with an active neuronal reuptake (U1) and/or an endothelial barrier. Using the microdialysis technique in eight anesthetized pigs, we investigated this NE gradient, both under baseline conditions and during increments in either systemic or myocardial interstitial fluid (MIF) NE concentration. At steady state, baseline MIF NE (0.9 +/- 0.1 nmol/l) was higher than arterial NE (0.3 +/- 0.1 nmol/l) but was not different from coronary venous NE (1.5 +/- 0.3 nmol/l). Local U1 inhibition raised MIF NE concentration to 6.5 +/- 0.9 nmol/l. During intravenous NE infusions (0.6 and 1.8 nmol. kg(-1). min(-1)), the fractional removal of NE by the myocardium was 79 +/- 4% to 69 +/- 3%, depending on the infusion rate. Despite this extensive removal, the quotient of changes in MIF and arterial concentration (DeltaMIF/DeltaA ratio) for NE were only 0.10 +/- 0.02 for the lower infusion rate and 0.11 +/- 0.01 for the higher infusion rate, whereas U1 blockade caused the DeltaMIF/DeltaA ratio to rise to 0.21 +/- 0.03 and 0.36 +/- 0.05, respectively. From the differences in DeltaMIF/DeltaA ratios with and without U1 inhibition, we calculated that 67 +/- 5% of MIF NE is removed by U1. Intracoronary infusion of tyramine (154 nmol. kg(-1). min(-1)) caused a 15-fold increase in MIF NE concentration. This pronounced increase was paralleled by a comparable increase of NE in the coronary vein. We conclude that U1 and extraneuronal uptake, and not an endothelial barrier, are the principal mechanisms underlying the concentration gradient of NE between the interstitial and intravascular compartments in the porcine heart.

Sensitive and specific method for the simultaneous determination of natural and synthetic catecholamines and 3,4-dihydroxyphenylglycol in microdialysis samples

The relatively new technique of microdialysis provides new possibilities for investigating in vivo the functioning of the sympathetic nervous system. The small sample volumes obtained, however, are a great challenge for analytical chemists. We report here a HPLC method for measuring in one run both natural and synthetic catecholamines [dopamine, (nor)epinephrine, alpha-methylnorepinephrine, isoproterenol and epinine] and the intraneuronal metabolite 3,4-dihydroxyphenylglycol in small microdialysis samples after derivatization with the fluorogenic agent 1,2-diphenylethylenediamine. No prior clean-up step is necessary. N-Ethylmaleimide is necessary for preventing an inhibitory action on derivatization occurring in in vivo microdialysis samples. The method can handle large numbers of samples, is sensitive (on-column detection limits 30 to 200 fg) and reproducible (RSD 1 to 7%). Recovery characteristics of the commercial microdialysis probe used (CMA/20) were extensively investigated both in vitro and in vivo at various perfusion rates; for practical purposes a rate of 2 microl/min and sampling at 10-min intervals was found to be workable and to give good and reproducible recoveries (50 to 70%).

Determination of semicarbazide-sensitive amine oxidase activity in human plasma by high-performance liquid chromatography with fluorimetric detection

We report here a simple and sensitive method for the measurement of semicarbazide-sensitive amine oxidase (SSAO) activity in human plasma. Benzaldehyde, generated during a 1-h incubation of plasma with benzylamine, is derivatized with the specific aldehyde reagent dimedone after prior deproteinization. Quantitation of the derivatization product is done by automated injection onto an isocratic high-performance liquid chromatographic system with fluorimetric detection. The assay shows good linearity and reproducibility (intra-assay C.V. 7%). Detection limit is 25 mU/l (= pmol/ml/min). In 51 healthy controls (age 49 +/- 13 yr, 20 males) the measured SSAO activity was 352 +/- 102 mU/l (mean +/- S.D.). A large number of samples (70-80) can easily be processed in one day by one technician.

Optimal collection and storage conditions for catecholamine measurements in human plasma and urine

Improvements in methodologies for measuring concentrations of catecholamines (CA) have led to an increasing use of these compounds as markers in the screening of patients and in long-term clinical trials. Because of the associated logistical problems, we have investigated the unresolved question of optimal conditions for sample preparation and for storage of plasma and urine samples. Results show that blood should be centrifuged within 1 h after collection; the use of a refrigerated centrifuge is not necessary. Once plasma is prepared, CA are stable for 1 day at 20 degrees C, 2 days at 4 degrees C, 1 month at -20 degrees C (or 6 months with added glutathione), and up to 1 year at -70 degrees C. CA are stable at 4 degrees C for 1 month in unpreserved urine and for 4 months in urine preserved with EDTA and sodium metabisulfite. In acidified urine, CA were nearly unchanged after 1 year at 4 and -20 degrees C.

Optimal collection and storage conditions for catecholamine measurements in human plasma and urine

Improvements in methodologies for measuring concentrations of catecholamines (CA) have led to an increasing use of these compounds as markers in the screening of patients and in long-term clinical trials. Because of the associated logistical problems, we have investigated the unresolved question of optimal conditions for sample preparation and for storage of plasma and urine samples. Results show that blood should be centrifuged within 1 h after collection; the use of a refrigerated centrifuge is not necessary. Once plasma is prepared, CA are stable for 1 day at 20 degrees C, 2 days at 4 degrees C, 1 month at -20 degrees C (or 6 months with added glutathione), and up to 1 year at -70 degrees C. CA are stable at 4 degrees C for 1 month in unpreserved urine and for 4 months in urine preserved with EDTA and sodium metabisulfite. In acidified urine, CA were nearly unchanged after 1 year at 4 and -20 degrees C.

Breakdown of 3,4-dihydroxybenzylamine and dopamine in plasma of various animal species by semicarbazide-sensitive amine oxidase

We report a rapid breakdown of dopamine and especially of 3,4-dihydroxybenzylamine, the frequently-used internal standard in catecholamine determinations, in plasma of many but not all animal species. Species investigated were cow, sheep, goat, pig, horse, rabbit, dog, guinea pig, mouse, chicken, rat and man. In some species 3,4-dihydroxybenzylamine nearly completely disappeared at 4 degrees C within 15 min after addition to the plasma. Added dopamine, but not norepinephrine and epinephrine, also rapidly disappeared at 4 degrees C. Disappearance rates were increased at higher temperatures, and at 20 degrees C also norepinephrine showed some breakdown. The breakdown is caused by a semicarbazide-sensitive amine oxidase in the plasma, and can be completely blocked by the addition of the inhibitor semicarbazide. Measurement of plasma catecholamine concentrations in animal species can thus lead to erroneous results, especially when 3,4-dihydroxybenzylamine is used as an internal standard. Only when blood is collected in tubes containing an inhibitor of semicarbazide-sensitive amine oxidase like semicarbazide can reliable plasma catecholamine measurements be performed.

Simultaneous determination of catecholamines and dobutamine in human plasma and urine by high-performance liquid chromatography with fluorimetric detection

We report a reliable fluorimetric assay for the simultaneous determination of norepinephrine, epinephrine, dopamine and dobutamine in human plasma and urine, based on liquid-liquid extraction and derivatization with the fluorogenic agent 1,2-diphenylethylenediamine prior to chromatography. The method is sensitive (detection limit 0.3-0.8 pg injected) and reproducible (coefficients of variation 1-10%), and shows good accuracy (93-98%). The method should also be used when one only wants to measure the concentrations of the natural catecholamines, in order to avoid interference by metabolites of dobutamine and by the late-eluting dobutamine itself.

Simultaneous determination of free catecholamines and epinine and estimation of total epinine and dopamine in plasma and urine by high-performance liquid chromatography with fluorimetric detection

Epinine (N-methyldopamine) is the pharmacologically active hydrolysis product of the prodrug ibopamine, which is currently being widely studied for the treatment of congestive heart failure. This paper reports a sensitive and reliable method for the simultaneous determination of free catecholamines and epinine in plasma and urine. The compounds are isolated from plasma or urine by a specific liquid-liquid extraction, derivatized with the selective fluorogenic agent 1,2-diphenylethylenediamine, and quantitated by high-performance liquid chromatography with gradient elution and fluorimetric detection. The limits of detection for the derivatized catecholamines and epinine are 0.3-0.6 pg of injected compound. Intra- and inter-assay coefficients of variation of all four compounds are good (1-8%), as are the accuracy and linearity. A method is also reported for the determination of total dopamine and epinine in plasma and urine based on the same principle. This method, in which deconjugation is accomplished by acid hydrolysis at 95 degrees C, also shows good sensitivity and reproducibility.