- Email: [email protected]
Subcutaneous Bupivacaine Infiltration and Postoperative Pain Perception After Percutaneous Nephrolithotomy
Subcutaneous Bupivacaine Infiltration and Postoperative Pain Perception After Percutaneous Nephrolithotomy George E. Haleblian,* Roger L. Sur,† David M. Albala‡ and Glenn M. Preminger§ From the Comprehensive Kidney Stone Center, Division of Urologic Surgery, Duke University Medical Center, Durham, North Carolina
Purpose: Recent studies have shown a significant decrease in patient reported pain scores when the nephrostomy tube size is decreased from 22 to 10Fr. We hypothesize that patient reported pain and narcotic use could be further decreased for patients with post-percutaneous nephrolithotomy nephrostomy tubes if the incision is infiltrated with a local anesthetic. Materials and Methods: A randomized prospective trial was designed to assess the impact of Marcaine® infiltration of the nephrostomy tract following percutaneous stone removal. Patients undergoing single access percutaneous nephrolithotomy were randomized to have a fixed volume of saline or weight based concentration of Marcaine infiltrated into the nephrostomy tube tract at the conclusion of the procedure. Postoperative narcotic use and patient reported pain scores were then obtained at 2, 4, 24 and 48 hours postoperatively. Results: A total of 25 patients were enrolled in the study with 3 excluded from analysis due to incomplete data collection (2) or the development of hydrothorax (1). Of the 22 patients analyzed 10 were in the Marcaine cohort and 12 were in the saline cohort. Patient pain scores at 2, 4, 24 and 28 hours for the Marcaine group were 5, 4.2, 3.6 and 2.6, while for the saline group scores were 3.3, 3.1, 2.3 and 3.5. At all points differences between the groups were not statistically significant (p ⬎0.05). Mean postoperative narcotic use was 24.7 mg morphine sulfate in the Marcaine group and 32.1 mg morphine sulfate in the control cohort (p ⬎0.05). Conclusions: In this preliminary pilot study no significant differences in patient reported pain scores were observed. However, a trend toward decreased postoperative narcotic use was seen in patients receiving subcutaneous Marcaine administration around the nephrostomy tube tract. Further studies are warranted to define additional measures to reduce discomfort in those requiring nephrostomy tube drainage following percutaneous nephrolithotomy. Key Words: nephrostomy, percutaneous; kidney calculi; pain
scores are lower when smaller 10Fr nephrostomy tubes are placed than when a traditional 22Fr nephrostomy is used. The infiltration of local anesthetic into surgical sites for control of postoperative pain has been well documented in prior studies literature. To further improve the patient experience after PNL we investigated the efficacy of subcutaneous 0.25% Marcaine infiltration into the nephrostomy tract on pain control for patients undergoing PNL requiring postoperative nephrostomy drainage.
ercutaneous nephrolithotomy is considered the standard of care for the treatment of large renal calculi. Since the first description of PNL in the late 1970s there have been many advances in equipment and technology to ease the removal of calculi and decrease patient morbidity. Procedures that initially required lengthy hospital stays are now done in many cases as an overnight procedure. One problematic area for pain control is the nephrostomy tube that is often left in place at the termination of the procedure. Recent trends toward not leaving a nephrostomy tube have gained favor. However, in cases where nephrostomy tubes are necessary, studies have shown that pain
P
MATERIALS AND METHODS After approval from the human research committee and institutional review board, a randomized prospective trial was designed to assess the impact of Marcaine infiltration of the nephrostomy tract following percutaneous stone removal. Adult patients with renal calculi measured as more than 2 cm on cross-sectional computerized tomography or excretory urography undergoing single access PNL were approached to participate in the study. Subjects were consented and randomized in a single blinded fashion (surgeon aware of group allocation) to 1 of 2 cohorts (group 1— Marcaine treatment and group 2— control). Preoperative narcotic use was standardized for all patients enrolled in the study to control for potential variability in drug administration by different anesthesiology staff. Intraoperatively a ureteral catheter was placed cystoscopically and percutaneous access was obtained after gen-
Submitted for publication January 18, 2007. Study received human research committee and institutional review board approval. * Correspondence: Division of Urologic Surgery, Box 3167, Room 1572 White Zone, Duke University Medical Center, Durham, North Carolina 27710 (telephone: 919-681-5506; FAX: 919-681-5507; e-mail: [email protected]). † Financial interest and/or other relationship with Boston Scientific and Intuitive Surgical, Inc. ‡ Financial interest and/or other relationship with American Medical Systems, Applied Medical, Sanofi-Aventis, Boehringer Ingelheim and GlaxoSmithKline. § Financial interest and/or other relationship with Boston Scientific, Olympus America Inc., Mission Pharmacal, Applied Urology and Onset Medical.
See Editorial on page 752.
0022-5347/07/1783-0925/0 THE JOURNAL OF UROLOGY® Copyright © 2007 by AMERICAN UROLOGICAL ASSOCIATION
925
Vol. 178, 925-928, September 2007 Printed in U.S.A. DOI:10.1016/j.juro.2007.05.025
926
PAIN PERCEPTION AFTER PERCUTANEOUS NEPHROLITHOTOMY
eral anesthesia was induced. Lithotripsy was performed with a LithoClast® Ultra or an Olympus® LUS-2 ultrasonic lithotrite. The treatment cohort (group 1) had 1.5 mg/kg of 0.25% Marcaine infiltrated with a 23 gauge needle into the subcutaneous tissues around the PNL access site after placement of a 10Fr nephrostomy tube. The control cohort (group 2) had 60 cc 0.9% saline infiltrated with the exact same technique because this volume approximates the average Marcaine volume. All patients received a standard postoperative pain control regimen of parenteral patient controlled narcotics for the first 12 hours and oral narcotics on demand thereafter. Patient pain scores were obtained by a research physician blinded to the randomization results with a validated linear VAS at 2 hours, 4 hours, 24 hours and 48 hours postoperatively. Postoperative narcotic analgesic use (parenteral and oral) was recorded and converted into morphine equivalents. The nephrostomy tube and ureteral catheter were removed before patient discharge home on postoperative day 2. A total of 25 patients were enrolled in the study with 3 patients excluded from analysis due to incomplete data collection (2) or the development of hydrothorax (1). Of the remaining 22 patients analyzed 10 were from the Marcaine cohort while the remaining 12 were from the saline cohort. Descriptive statistics including mean, median, standard deviation, interquartile range, frequencies, proportions and graphical displays were computed. Because the distribution of mean pain scores was normal, the unpaired Student t test with 2-tailed p values and ␣ ⫽ 0.05 was conducted using SPSS® version 12.0.1.
RESULTS Demographics were similar between the cohorts with respect to height, weight and age as outlined in the table. Intraoperative characteristics of the 2 groups were similar with mean operative times of 116 and 123 minutes, and mean blood loss reported as 113 and 67 cc for the saline and Marcaine cohorts, respectively. Pain scores are shown in figure 1 with no statistically significant differences between cohorts in perceived pain at any of the time intervals. While there was no statistically significant difference in VAS pain scores between the 2 cohorts, analgesic use for the patients randomized to receive Marcaine infiltration appeared lower (fig. 2). Overall narcotic use was 24.7 mg in the Marcaine group and 32.1 mg in the control patients, although this finding was not statistically significant (p ⫽ 0.46).
Patient demographics and operative parameters
Age p Value Ht (cm) p Value Wt (kg) p Value Operative mins p Value Estimated blood loss (cc) p Value
Saline Group
Marcaine Group
44.9
45.7 0.97 165 0.07 94.1 0.66 123 0.74 67 0.48
172 89.5 116 113
DISCUSSION The treatment of renal calculi has evolved during the last 30 years from open stone extraction to less invasive modalities such as shock wave lithotripsy and endoscopic stone fragmentation, including percutaneous stone removal and ureteroscopy. The surgical approach to renal calculi depends largely on stone size, location and composition. A renal calculus greater than 2 cm usually requires a percutaneous approach to provide adequate access to the calculus to render the patient stone-free with a single procedure. Since its original description, technological advances in lithotriptors and related equipment have improved the efficacy and safety of percutaneous nephrolithotomy such that this procedure remains the standard of care for the treatment of large or complex renal calculi. Traditionally after completion of PNL a 22Fr nephrostomy tube was placed for 48 hours and removed before patient discharge home. However, more recently studies have suggested that tubeless PNL procedures significantly reduced postoperative discomfort following PNL.1– 4 However, in patients requiring nephrostomy after PNL, studies have suggested that the use of a 10Fr nephrostomy tube reduced patient reported pain scores immediately following surgery, with a trend toward decreased postoperative narcotic use compared to the use of a 22Fr nephrostomy tube.4,5 However, there are cases in which nephrostomy tube placement is required, primarily for large complex stones where there may be a caliceal tear or bleeding at the termination of the procedure. Others are still reluctant to perform tubeless PNL since the theoretical benefit is offset by the need for an outpatient procedure to remove the indwelling ureteral stent. Numerous studies in the anesthesia, surgery and gynecology literature have described the efficacy of local anesthetic infiltration in surgical incisions. These include efficacy in cesarean sections, thyroid surgery and mastectomy.6 – 8 In the urology literature further evidence of efficacy of local anesthesia is based on reports of varicocele ligation with the patient under local anesthesia.9,10 The use of Marcaine as the local anesthetic has also been widely reported but none have described local Marcaine used at the PNL site.11–13 To our knowledge this is the first study to demonstrate the use of this medication and the effect on patient perceived pain as well as postoperative narcotic use. Although no significant difference in postoperative pain scores between the 2 cohorts was identified, we noted decreased total narcotic use in the Marcaine cohort. Because there were no previous studies available to calculate a power analysis a priori, in a post hoc analysis this study is shown to probably be underpowered (sample size requires total number of 49 with current data). Therefore, the investigation is not necessarily a negative study as much as it is inconclusive given its current state as a pilot study. The current protocol was a pilot study in inception and suggests that further studies with a larger sample size are necessary for definitive conclusions on the efficacy of Marcaine following PNL. Other theories for this unexpected finding include variations in patient pain thresholds for requiring medication and reporting of pain scores on the VAS as all patients had on demand narcotic medication during the immediate postoperative period. Availability of narcotic medication based on prescriber preferences was not a confounding factor. Patient demographics suggest that there was no statis-
PAIN PERCEPTION AFTER PERCUTANEOUS NEPHROLITHOTOMY
927
FIG. 1. Postoperative mean patient reported pain scores
tically significant difference in the 2 cohorts, thereby eliminating other confounding factors in pain perception such as age. Preemptive anesthetic theory suggests that the study may have been more efficacious if the Marcaine was given before the initial incision. Many believe that blockade of the pain fibers must occur before incision to provide maximal benefit.14,15 In contrast, our study used infiltration of Marcaine or placebo at the end as opposed to the beginning of the procedure. These limitations notwithstanding, we believe the importance of this study in the current format still holds clinical value because it adds valuable information on the efficacy
(or lack thereof) of Marcaine use after PNL procedures. Ideally our data will be confirmed in other studies to verify our conclusions. Representation of negative studies demonstrates a trend to minimize publication bias and pool all data regardless of magnitude and direction.16 CONCLUSIONS In this preliminary study of postoperative pain perception after infiltration of subcutaneous Marcaine into the nephrostomy tube tract after PNL, no significant difference in patient reported pain scores was observed compared to placebo. A trend toward decreased narcotic use was noted in
FIG. 2. Total narcotic use during initial 48-hour postoperative period
928
PAIN PERCEPTION AFTER PERCUTANEOUS NEPHROLITHOTOMY
those patients in the Marcaine cohort. Further studies are warranted to define additional measures to reduce discomfort for those individuals requiring nephrostomy tube drainage after PNL.
8.
Abbreviations and Acronyms PNL ⫽ percutaneous nephrolithotomy VAS ⫽ visual analogue scale
9.
REFERENCES 1.
2.
3.
4.
5.
6.
7.
Bellman GC, Davidoff R, Candela J, Gerspach J, Kurtz S and Stout L: Tubeless percutaneous renal surgery. J Urol 1997; 157: 1578. Candela J, Davidoff R, Gerspach J and Bellman GC: “Tubeless” percutaneous surgery: a new advance in the technique of percutaneous renal surgery. Tech Urol 1997; 3: 6. Choi M and Bellman G: Prospective randomized trial comparing small bore percutaneous tube vs tubeless percutaneous nephrostolithotomy with tailed stent. J Endourol, suppl., 2005; 19: A71. Desai MR, Kukreja RA, Desai MM, Mhaskar SS, Wani KA, Patel SH et al: A prospective randomized comparison of type of nephrostomy drainage following percutaneous nephrostolithotomy: large bore versus small bore versus tubeless. J Urol 2004; 172: 565. Pietrow PK, Auge BK, Lallas CD, Santa-Cruz RW, Newman GE, Albala DM et al: Pain after percutaneous nephrolithotomy: impact of nephrostomy tube size. J Endourol 2003; 17: 411. Bagul A, Taha R, Metcalfe MS, Brook NR and Nicholson ML: Pre-incision infiltration of local anesthetic reduces postoperative pain with no effects on bruising and wound cosmesis after thyroid surgery. Thyroid 2005; 15: 1245. Ranta PO, Ala-Kokko TI, Kukkonen JE, Ohtonen PP, Raudaskoski TH, Reponen PK et al: Incisional and epidural
10.
11.
12.
13.
14.
15.
16.
analgesia after caesarean delivery: a prospective, placebocontrolled, randomised clinical study. Int J Obstet Anesth 2006; 15: 189. Rawal N, Gupta A, Helsing M, Grell K and Allvin R: Pain relief following breast augmentation surgery: a comparison between incisional patient-controlled regional analgesia and traditional oral analgesia. Eur J Anaesthesiol 2006; 23: 1010. Gontero P, Pretti G, Fontana F, Zitella A, Marchioro G and Frea B: Inguinal versus subinguinal varicocele vein ligation using magnifying loupe under local anesthesia: which technique is preferable in clinical practice? Urology 2005; 66: 1075. Hsu GL, Ling PY, Hsieh CH, Wang CJ, Chen CW, Wen HS et al: Outpatient varicocelectomy performed under local anesthesia. Asian J Androl 2005; 7: 439. Biboulet P, Morau D, Aubas P, Bringuier-Branchereau S and Capdevila X: Postoperative analgesia after total-hip arthroplasty: Comparison of intravenous patient-controlled analgesia with morphine and single injection of femoral nerve or psoas compartment block. a prospective, randomized, double-blind study. Reg Anesth Pain Med 2004; 29: 102. Ng A, Swami A, Smith G, Davidson AC and Emembolu J: The analgesic effects of intraperitoneal and incisional bupivacaine with epinephrine after total abdominal hysterectomy. Anesth Analg 2002; 95: 158. Pobereskin LH and Sneyd JR: Wound infiltration with bupivacaine after surgery to the cervical spine using a posterior approach. Br J Anaesth 2000; 84: 87. Fletcher D, Zetlaoui P, Monin S, Bombart M and Samii K: Influence of timing on the analgesic effect of intravenous ketorolac after orthopedic surgery. Pain 1995; 61: 291. Coderre TJ, Katz J, Vaccarino AL and Melzack R: Contribution of central neuroplasticity to pathological pain: review of clinical and experimental evidence. Pain 1993; 52: 259. Montori VM, Smieja M and Guyatt GH: Publication bias: a brief review for clinicians. Mayo Clin Proc 2000; 75: 1284.
Purpose: Recent studies have shown a significant decrease in patient reported pain scores when the nephrostomy tube size is decreased from 22 to 10Fr. We hypothesize that patient reported pain and narcotic use could be further decreased for patients with post-percutaneous nephrolithotomy nephrostomy tubes if the incision is infiltrated with a local anesthetic. Materials and Methods: A randomized prospective trial was designed to assess the impact of Marcaine® infiltration of the nephrostomy tract following percutaneous stone removal. Patients undergoing single access percutaneous nephrolithotomy were randomized to have a fixed volume of saline or weight based concentration of Marcaine infiltrated into the nephrostomy tube tract at the conclusion of the procedure. Postoperative narcotic use and patient reported pain scores were then obtained at 2, 4, 24 and 48 hours postoperatively. Results: A total of 25 patients were enrolled in the study with 3 excluded from analysis due to incomplete data collection (2) or the development of hydrothorax (1). Of the 22 patients analyzed 10 were in the Marcaine cohort and 12 were in the saline cohort. Patient pain scores at 2, 4, 24 and 28 hours for the Marcaine group were 5, 4.2, 3.6 and 2.6, while for the saline group scores were 3.3, 3.1, 2.3 and 3.5. At all points differences between the groups were not statistically significant (p ⬎0.05). Mean postoperative narcotic use was 24.7 mg morphine sulfate in the Marcaine group and 32.1 mg morphine sulfate in the control cohort (p ⬎0.05). Conclusions: In this preliminary pilot study no significant differences in patient reported pain scores were observed. However, a trend toward decreased postoperative narcotic use was seen in patients receiving subcutaneous Marcaine administration around the nephrostomy tube tract. Further studies are warranted to define additional measures to reduce discomfort in those requiring nephrostomy tube drainage following percutaneous nephrolithotomy. Key Words: nephrostomy, percutaneous; kidney calculi; pain
scores are lower when smaller 10Fr nephrostomy tubes are placed than when a traditional 22Fr nephrostomy is used. The infiltration of local anesthetic into surgical sites for control of postoperative pain has been well documented in prior studies literature. To further improve the patient experience after PNL we investigated the efficacy of subcutaneous 0.25% Marcaine infiltration into the nephrostomy tract on pain control for patients undergoing PNL requiring postoperative nephrostomy drainage.
ercutaneous nephrolithotomy is considered the standard of care for the treatment of large renal calculi. Since the first description of PNL in the late 1970s there have been many advances in equipment and technology to ease the removal of calculi and decrease patient morbidity. Procedures that initially required lengthy hospital stays are now done in many cases as an overnight procedure. One problematic area for pain control is the nephrostomy tube that is often left in place at the termination of the procedure. Recent trends toward not leaving a nephrostomy tube have gained favor. However, in cases where nephrostomy tubes are necessary, studies have shown that pain
P
MATERIALS AND METHODS After approval from the human research committee and institutional review board, a randomized prospective trial was designed to assess the impact of Marcaine infiltration of the nephrostomy tract following percutaneous stone removal. Adult patients with renal calculi measured as more than 2 cm on cross-sectional computerized tomography or excretory urography undergoing single access PNL were approached to participate in the study. Subjects were consented and randomized in a single blinded fashion (surgeon aware of group allocation) to 1 of 2 cohorts (group 1— Marcaine treatment and group 2— control). Preoperative narcotic use was standardized for all patients enrolled in the study to control for potential variability in drug administration by different anesthesiology staff. Intraoperatively a ureteral catheter was placed cystoscopically and percutaneous access was obtained after gen-
Submitted for publication January 18, 2007. Study received human research committee and institutional review board approval. * Correspondence: Division of Urologic Surgery, Box 3167, Room 1572 White Zone, Duke University Medical Center, Durham, North Carolina 27710 (telephone: 919-681-5506; FAX: 919-681-5507; e-mail: [email protected]). † Financial interest and/or other relationship with Boston Scientific and Intuitive Surgical, Inc. ‡ Financial interest and/or other relationship with American Medical Systems, Applied Medical, Sanofi-Aventis, Boehringer Ingelheim and GlaxoSmithKline. § Financial interest and/or other relationship with Boston Scientific, Olympus America Inc., Mission Pharmacal, Applied Urology and Onset Medical.
See Editorial on page 752.
0022-5347/07/1783-0925/0 THE JOURNAL OF UROLOGY® Copyright © 2007 by AMERICAN UROLOGICAL ASSOCIATION
925
Vol. 178, 925-928, September 2007 Printed in U.S.A. DOI:10.1016/j.juro.2007.05.025
926
PAIN PERCEPTION AFTER PERCUTANEOUS NEPHROLITHOTOMY
eral anesthesia was induced. Lithotripsy was performed with a LithoClast® Ultra or an Olympus® LUS-2 ultrasonic lithotrite. The treatment cohort (group 1) had 1.5 mg/kg of 0.25% Marcaine infiltrated with a 23 gauge needle into the subcutaneous tissues around the PNL access site after placement of a 10Fr nephrostomy tube. The control cohort (group 2) had 60 cc 0.9% saline infiltrated with the exact same technique because this volume approximates the average Marcaine volume. All patients received a standard postoperative pain control regimen of parenteral patient controlled narcotics for the first 12 hours and oral narcotics on demand thereafter. Patient pain scores were obtained by a research physician blinded to the randomization results with a validated linear VAS at 2 hours, 4 hours, 24 hours and 48 hours postoperatively. Postoperative narcotic analgesic use (parenteral and oral) was recorded and converted into morphine equivalents. The nephrostomy tube and ureteral catheter were removed before patient discharge home on postoperative day 2. A total of 25 patients were enrolled in the study with 3 patients excluded from analysis due to incomplete data collection (2) or the development of hydrothorax (1). Of the remaining 22 patients analyzed 10 were from the Marcaine cohort while the remaining 12 were from the saline cohort. Descriptive statistics including mean, median, standard deviation, interquartile range, frequencies, proportions and graphical displays were computed. Because the distribution of mean pain scores was normal, the unpaired Student t test with 2-tailed p values and ␣ ⫽ 0.05 was conducted using SPSS® version 12.0.1.
RESULTS Demographics were similar between the cohorts with respect to height, weight and age as outlined in the table. Intraoperative characteristics of the 2 groups were similar with mean operative times of 116 and 123 minutes, and mean blood loss reported as 113 and 67 cc for the saline and Marcaine cohorts, respectively. Pain scores are shown in figure 1 with no statistically significant differences between cohorts in perceived pain at any of the time intervals. While there was no statistically significant difference in VAS pain scores between the 2 cohorts, analgesic use for the patients randomized to receive Marcaine infiltration appeared lower (fig. 2). Overall narcotic use was 24.7 mg in the Marcaine group and 32.1 mg in the control patients, although this finding was not statistically significant (p ⫽ 0.46).
Patient demographics and operative parameters
Age p Value Ht (cm) p Value Wt (kg) p Value Operative mins p Value Estimated blood loss (cc) p Value
Saline Group
Marcaine Group
44.9
45.7 0.97 165 0.07 94.1 0.66 123 0.74 67 0.48
172 89.5 116 113
DISCUSSION The treatment of renal calculi has evolved during the last 30 years from open stone extraction to less invasive modalities such as shock wave lithotripsy and endoscopic stone fragmentation, including percutaneous stone removal and ureteroscopy. The surgical approach to renal calculi depends largely on stone size, location and composition. A renal calculus greater than 2 cm usually requires a percutaneous approach to provide adequate access to the calculus to render the patient stone-free with a single procedure. Since its original description, technological advances in lithotriptors and related equipment have improved the efficacy and safety of percutaneous nephrolithotomy such that this procedure remains the standard of care for the treatment of large or complex renal calculi. Traditionally after completion of PNL a 22Fr nephrostomy tube was placed for 48 hours and removed before patient discharge home. However, more recently studies have suggested that tubeless PNL procedures significantly reduced postoperative discomfort following PNL.1– 4 However, in patients requiring nephrostomy after PNL, studies have suggested that the use of a 10Fr nephrostomy tube reduced patient reported pain scores immediately following surgery, with a trend toward decreased postoperative narcotic use compared to the use of a 22Fr nephrostomy tube.4,5 However, there are cases in which nephrostomy tube placement is required, primarily for large complex stones where there may be a caliceal tear or bleeding at the termination of the procedure. Others are still reluctant to perform tubeless PNL since the theoretical benefit is offset by the need for an outpatient procedure to remove the indwelling ureteral stent. Numerous studies in the anesthesia, surgery and gynecology literature have described the efficacy of local anesthetic infiltration in surgical incisions. These include efficacy in cesarean sections, thyroid surgery and mastectomy.6 – 8 In the urology literature further evidence of efficacy of local anesthesia is based on reports of varicocele ligation with the patient under local anesthesia.9,10 The use of Marcaine as the local anesthetic has also been widely reported but none have described local Marcaine used at the PNL site.11–13 To our knowledge this is the first study to demonstrate the use of this medication and the effect on patient perceived pain as well as postoperative narcotic use. Although no significant difference in postoperative pain scores between the 2 cohorts was identified, we noted decreased total narcotic use in the Marcaine cohort. Because there were no previous studies available to calculate a power analysis a priori, in a post hoc analysis this study is shown to probably be underpowered (sample size requires total number of 49 with current data). Therefore, the investigation is not necessarily a negative study as much as it is inconclusive given its current state as a pilot study. The current protocol was a pilot study in inception and suggests that further studies with a larger sample size are necessary for definitive conclusions on the efficacy of Marcaine following PNL. Other theories for this unexpected finding include variations in patient pain thresholds for requiring medication and reporting of pain scores on the VAS as all patients had on demand narcotic medication during the immediate postoperative period. Availability of narcotic medication based on prescriber preferences was not a confounding factor. Patient demographics suggest that there was no statis-
PAIN PERCEPTION AFTER PERCUTANEOUS NEPHROLITHOTOMY
927
FIG. 1. Postoperative mean patient reported pain scores
tically significant difference in the 2 cohorts, thereby eliminating other confounding factors in pain perception such as age. Preemptive anesthetic theory suggests that the study may have been more efficacious if the Marcaine was given before the initial incision. Many believe that blockade of the pain fibers must occur before incision to provide maximal benefit.14,15 In contrast, our study used infiltration of Marcaine or placebo at the end as opposed to the beginning of the procedure. These limitations notwithstanding, we believe the importance of this study in the current format still holds clinical value because it adds valuable information on the efficacy
(or lack thereof) of Marcaine use after PNL procedures. Ideally our data will be confirmed in other studies to verify our conclusions. Representation of negative studies demonstrates a trend to minimize publication bias and pool all data regardless of magnitude and direction.16 CONCLUSIONS In this preliminary study of postoperative pain perception after infiltration of subcutaneous Marcaine into the nephrostomy tube tract after PNL, no significant difference in patient reported pain scores was observed compared to placebo. A trend toward decreased narcotic use was noted in
FIG. 2. Total narcotic use during initial 48-hour postoperative period
928
PAIN PERCEPTION AFTER PERCUTANEOUS NEPHROLITHOTOMY
those patients in the Marcaine cohort. Further studies are warranted to define additional measures to reduce discomfort for those individuals requiring nephrostomy tube drainage after PNL.
8.
Abbreviations and Acronyms PNL ⫽ percutaneous nephrolithotomy VAS ⫽ visual analogue scale
9.
REFERENCES 1.
2.
3.
4.
5.
6.
7.
Bellman GC, Davidoff R, Candela J, Gerspach J, Kurtz S and Stout L: Tubeless percutaneous renal surgery. J Urol 1997; 157: 1578. Candela J, Davidoff R, Gerspach J and Bellman GC: “Tubeless” percutaneous surgery: a new advance in the technique of percutaneous renal surgery. Tech Urol 1997; 3: 6. Choi M and Bellman G: Prospective randomized trial comparing small bore percutaneous tube vs tubeless percutaneous nephrostolithotomy with tailed stent. J Endourol, suppl., 2005; 19: A71. Desai MR, Kukreja RA, Desai MM, Mhaskar SS, Wani KA, Patel SH et al: A prospective randomized comparison of type of nephrostomy drainage following percutaneous nephrostolithotomy: large bore versus small bore versus tubeless. J Urol 2004; 172: 565. Pietrow PK, Auge BK, Lallas CD, Santa-Cruz RW, Newman GE, Albala DM et al: Pain after percutaneous nephrolithotomy: impact of nephrostomy tube size. J Endourol 2003; 17: 411. Bagul A, Taha R, Metcalfe MS, Brook NR and Nicholson ML: Pre-incision infiltration of local anesthetic reduces postoperative pain with no effects on bruising and wound cosmesis after thyroid surgery. Thyroid 2005; 15: 1245. Ranta PO, Ala-Kokko TI, Kukkonen JE, Ohtonen PP, Raudaskoski TH, Reponen PK et al: Incisional and epidural
10.
11.
12.
13.
14.
15.
16.
analgesia after caesarean delivery: a prospective, placebocontrolled, randomised clinical study. Int J Obstet Anesth 2006; 15: 189. Rawal N, Gupta A, Helsing M, Grell K and Allvin R: Pain relief following breast augmentation surgery: a comparison between incisional patient-controlled regional analgesia and traditional oral analgesia. Eur J Anaesthesiol 2006; 23: 1010. Gontero P, Pretti G, Fontana F, Zitella A, Marchioro G and Frea B: Inguinal versus subinguinal varicocele vein ligation using magnifying loupe under local anesthesia: which technique is preferable in clinical practice? Urology 2005; 66: 1075. Hsu GL, Ling PY, Hsieh CH, Wang CJ, Chen CW, Wen HS et al: Outpatient varicocelectomy performed under local anesthesia. Asian J Androl 2005; 7: 439. Biboulet P, Morau D, Aubas P, Bringuier-Branchereau S and Capdevila X: Postoperative analgesia after total-hip arthroplasty: Comparison of intravenous patient-controlled analgesia with morphine and single injection of femoral nerve or psoas compartment block. a prospective, randomized, double-blind study. Reg Anesth Pain Med 2004; 29: 102. Ng A, Swami A, Smith G, Davidson AC and Emembolu J: The analgesic effects of intraperitoneal and incisional bupivacaine with epinephrine after total abdominal hysterectomy. Anesth Analg 2002; 95: 158. Pobereskin LH and Sneyd JR: Wound infiltration with bupivacaine after surgery to the cervical spine using a posterior approach. Br J Anaesth 2000; 84: 87. Fletcher D, Zetlaoui P, Monin S, Bombart M and Samii K: Influence of timing on the analgesic effect of intravenous ketorolac after orthopedic surgery. Pain 1995; 61: 291. Coderre TJ, Katz J, Vaccarino AL and Melzack R: Contribution of central neuroplasticity to pathological pain: review of clinical and experimental evidence. Pain 1993; 52: 259. Montori VM, Smieja M and Guyatt GH: Publication bias: a brief review for clinicians. Mayo Clin Proc 2000; 75: 1284.