- Email: [email protected]
Serum Laboratory Values Following Uncomplicated Laparoscopic Urological Surgery
Serum Laboratory Values Following Uncomplicated Laparoscopic Urological Surgery J. Kyle Anderson, Edward D. Matsumoto, Khaled Abdel-Aziz, Robert Svatek and Jeffrey A. Cadeddu* From the Clinical Center for Minimally Invasive Urologic Cancer Treatment, Department of Urology, University of Texas Southwestern Medical Center, Dallas, Texas
Purpose: Presentation of complications following laparoscopic surgery can be different from corresponding open surgical complications. While leukopenia has been identified as a common finding in patients with unrecognized bowel injury following laparoscopy, to our knowledge no study has determined if leukopenia or other serum abnormalities are unique to patients with laparoscopic complications. We present an analysis of postoperative laboratory values from patients after uncomplicated urological laparoscopic surgery. Materials and Methods: A retrospective review of 50 adult patients who had previously undergone uncomplicated laparoscopic urological procedures was performed. Exclusion criteria were preexisting hematological, immune, liver or pancreatic disorders. Common serum laboratory values were measured on postoperative day 1. Results: All values for bilirubin were within normal limits. Of patients undergoing a right side renal procedure, 10 of 16 (63%) had a postoperative increase in liver function tests. Amylase or lipase was increased in a total of 12 (24%) patients. Patients undergoing laparoscopic prostatectomy accounted for the majority of this group with 9 of 21 (43%) patients having increased amylase or lipase. Finally, there were no patients with immediate postoperative leukopenia. Conclusions: Following uncomplicated laparoscopic procedures, bilirubin levels are rarely affected, amylase and lipase may be acutely increased following laparoscopic prostatectomy, and white blood count is commonly increased. While 16 (36%) patients had postoperative leukocytosis, leukopenia was not detected after uncomplicated laparoscopic urological surgery and should alert the surgeon to the possibility of an undiagnosed complication. Key Words: laparoscopy, serum, leukocyte count, amylases, lipase
from 50 patients following uncomplicated urological laparoscopic surgery.
ince the introduction of laparoscopic nephrectomy in 1991,1 laparoscopy has been increasingly used as a treatment modality for several urological diseases. While complication rates from laparoscopic procedures are comparable to those of their open counterparts,2-5 complications obviously occur. More importantly the presentation of these complications can be quite different following laparoscopic vs open procedures. The best studied example is bowel injury. Bishoff et al noted that subjects with bowel injury occurring during laparoscopy did not present with classic peritoneal signs and fever, but instead had trocar site pain, abdominal distention, leukopenia and diarrhea. Of these signs and symptoms leukopenia was quite prominent, occurring in 80% of patients with unrecognized bowel injuries.6 Although laboratory findings such as leukopenia are clearly important in the evaluation for laparoscopic complications, we could find no study following uncomplicated laparoscopy to determine if leukopenia or other serum abnormalities are unique to patients with complications. Thus, we present an analysis of postoperative laboratory values
S
MATERIALS AND METHODS After institutional review board approval, a retrospective review of medical records of 50 patients who had previously undergone uncomplicated laparoscopic urological procedures and had postoperative serum blood work available was performed. These procedures were performed between December 2003 and September 2004. Inclusion criteria were patients undergoing an elective laparoscopic procedure and age greater than 18 years old. Exclusion criteria were preexisting hematological, immune, liver or pancreatic disorder. Patients with intraoperative or postoperative early or late complications, or use of immunosuppressive medication, were also excluded from analysis. Hand assistance was not used in any of the included procedures. Serum laboratory tests were drawn on postoperative day 1 following the respective surgery. Blood work was generally not drawn on subsequent days as there was no clinical indication or the patient was discharged from the hospital. Serum tests consisted of WBC, AST, ALT, GGT, total bilirubin, direct bilirubin, indirect bilirubin, amylase and lipase. Standard laboratory techniques were used to obtain serum values. More specifically WBC and platelet levels were obtained using a cell counter (Coulter® Gen䡠S™ Sys-
Submitted for publication March 7, 2005 Study received institutional review board approval. * Correspondence: Department of Urology, The University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, Texas 75390-9110 (telephone: 214-648-2888; FAX: 214-6488786; e-mail: [email protected]).
0022-5347/06/1751-0167/0 THE JOURNAL OF UROLOGY® Copyright © 2006 by AMERICAN UROLOGICAL ASSOCIATION
167
Vol. 175, 167-169, January 2006 Printed in U.S.A. DOI:10.1016/S0022-5347(05)00045-5
168 SERUM LABORATORY VALUES AFTER UNCOMPLICATED LAPAROSCOPIC UROLOGICAL SURGERY TABLE 1. Patient data by procedure Laparoscopic Procedure
No. Pts (%)
No. Male/Female (%)
No. Rt/Lt (%)
Mean Days Hospital Stay
Prostatectomy Nephrectomy Partial nephrectomy Pyeloplasty Cyst decortication Retroperitoneal lymph node dissection Adrenalectomy
21 (42) 12 (24) 9 (18) 3 (6) 2 (4) 2 (4) 1 (2)
21 (100)/6 (50)/6 (50) 7 (78)/2 (22) 2 (67)/1 (33) 0/2 (100) 2 (100)/0/1 (100)
7 (58)/5 (42) 5 (56)/4 (44) 2 (67)/1 (33) 2 (100)/0 1 (50)/1 (50) 0/1 (100)
1.7 2.6 2.6 2.3 2.0 1.5 3.0
tem 2), and all remaining tests were performed using a chemistry immuno analyzer (Olympus AU400e®). SigmaStat® software was used to perform the chi-square and Mann-Whitney rank sum statistical tests. RESULTS Of the 50 patients included in analysis 38 were male and 12 were female. Mean age was 56 years (range 25 to 75). Laparoscopic procedures included prostatectomy, nephrectomy, pyeloplasty, retroperitoneal lymph node dissection, renal cyst decortication and adrenalectomy. Table 1 shows patient and operative data for each of these procedure groups. Table 2 presents low values, Nl values and increased values for each laboratory test. Increased values are further divided into those increased 1 to 1.5 times, 1.5 to 2 times and greater than 2 times the maximal normal value. Of note, 5 of 6 (83%) and 7 of 8 (88%) patients with increased AST and ALT, respectively, had undergone right side renal procedures. The 2 episodes of increased GGT were following right side renal procedures as well. Thus, of the 16 right side renal procedures performed, 10 (63%) had subsequent increases in AST, ALT or GGT. There was no increase in these liver enzymes following left side renal procedures, and total, direct and indirect bilirubin remained within normal limits regardless of whether the operative site involved the right kidney. Regarding other laboratory tests, increases in amylase and lipase did not correspond to procedures in the left upper quadrant of the abdomen. Instead 9 of 12 (75%) patients with increased amylase or lipase had undergone laparoscopic prostatectomy. This increase in patients who had undergone prostatectomy approached statistical significance (Mann-Whitney rank sum test p ⫽ 0.052) with 9 of 21 (42%) patients having a postoperative increase in amylase or lipase. Thrombocytopenia was a common finding in 10 of 50 (20%) patients but was not correlated with any specific procedure or intraoperative intravenous volume administra-
tion. Estimated blood loss was examined as well, but there was no correlation between this value and the presence of a laboratory abnormality (chi-square test p ⫽ 0.668). Finally and most importantly, while 16 of 50 (32%) patients had postoperative leukocytosis, not a single episode of leukopenia was encountered. DISCUSSION To our knowledge this is the first study to evaluate postoperative laboratory values following uncomplicated laparoscopic urological procedures. We included a variety of laparoscopic procedures for indications ranging from cancer (prostate, renal cell and testis) to renal obstruction (ureteropelvic junction obstruction) to chronic pain (symptomatic renal cysts). The serum laboratory results following these procedures provide a standard for the expected values for an uncomplicated laparoscopic surgery, thus improving interpretation of postoperative laboratory values in patients with suspected complications. After right side renal procedures, increases in AST, ALT and GGT were common. Given the nature of these surgeries, with frequent manipulation of the liver, this comes as little surprise. In fact, increases in these enzymes after laparoscopic cholecystectomy have been well documented.7-9 Their increase after other laparoscopic procedures has also been noted and possibly attributed to carbon dioxide pneumoperitoneum.6,8 On the other hand, bilirubin measurements are infrequently affected by any of the surgeries performed here, thus significant postoperative abnormalities should prompt further investigation. More difficult to explain is the correlation of increased amylase and lipase with laparoscopic prostatectomy. There is no direct manipulation of the pancreas or any surrounding structure during this procedure and pancreatitis is not commonly encountered. In addition, these increases in amylase and lipase are not likely related to prostate surgery itself as neither increase of these enzymes nor pancreatitis is commonly reported following open
TABLE 2. Serum laboratory values following uncomplicated laparoscopic procedures No. (%) Value (NI range)
Below Nl Min
NI
1–1.5 ⫻ Nl
1.5–2 ⫻ Nl
Greater Than 2 ⫻ Nl
WBC (4.1–11 ⫻ 103/ul) Platelets (140–440 ⫻ 103/u/l) Amylase (29–108 U/l) Lipase (7–59 U/l) AST (13–40 U/l) ALT (13–40 U/l) GGT (8–78 U/l) Total bilirubin (0.2–1.3 mg/dl) Direct bilirubin (0.0–0.3 mg/dl) Indirect bilirubin (0.0–0.9 mg/dl)
0 10 (23) 8 (17) 8 (17) 1 (2) 1 (2) 0 0 0 0
29 (64) 33 (77) 34 (71) 31 (65) 41 (86) 39 (82) 40 (93) 46 (100) 39 (93) 33 (100)
11 (25) 0 1 (2) 5 (10) 4 (8) 5 (10) 2 (5) 0 0 0
4 (9) 0 2 (4) 3 (6) 1 (2) 1 (2) 1 (2) 0 1 (2) 0
1 (2) 0 3 (6) 1 (2) 1 (2) 2 (4) 0 0 2 (5) 0
SERUM LABORATORY VALUES AFTER UNCOMPLICATED LAPAROSCOPIC UROLOGICAL SURGERY 169 radical prostatectomy. One possible explanation for this abnormality would be the extreme Trendelenburg position required for the duration of this surgery, but it is not clear how this would lead to the increase in pancreatic enzymes. The final and most important finding was the absence of leukopenia in this patient group. Leukopenia has previously been identified as a common presenting sign of unrecognized bowel injury. This was noted by Bishoff et al after reviewing 915 laparoscopic urological procedures and finding that 4 of the 5 patients with unrecognized bowel perforation had leukopenia.6 The only signs or symptoms that were more prevalent were trocar site pain and abdominal distention, which were present in all 5 patients. It is also important to note that 2 of the 5 patients with unrecognized bowel injuries died secondary to this complication, confirming the significant morbidity/mortality of this complication. As such, postoperative leukopenia is not an expected finding and should raise clinical concerns. Weaknesses of this study include its retrospective design, small sample size and the resulting lack of followup laboratory testing on patients with laboratory abnormalities. Ideally a much larger sample of subjects, powered appropriately and assessed prospectively following a wide variety of procedures, would address this weakness, and give further insight into the significance of increases in amylase and lipase following laparoscopy.
CONCLUSIONS Diagnosis of complications following laparoscopic procedures can be difficult as presentation is often subtle and different from that of open surgery. Our experience suggests that increases in liver and pancreatic enzymes are common but the presence of leukopenia is not encountered following uncomplicated procedures. Thus, the presence of leukopenia should alert the laparoscopic surgeon to the possibility of an unrecognized complication, especially bowel injury.
Abbreviations and Acronyms AST ALT GGT Nl WBC
⫽ ⫽ ⫽ ⫽ ⫽
aspartate aminotransferase alanine aminotransferase ␥-glutamyltransferase normal white blood count
REFERENCES 1. Clayman, R. V., Kavoussi, L. R., Soper, N. J., Dierks, S. M., Meretyk, S., Darcy, M. D. et al: Laparoscopic nephrectomy: initial case report. J Urol, 146: 278, 1991 2. Dunn, M. D., Portis, A. J., Shalhav, A. L., Elbahnasy, A. M., Heidorn, C., McDougall, E. M. et al: Laparoscopic versus open radical nephrectomy: a 9-year experience. J Urol, 164: 1153, 2000 3. Gill, I. S., Matin, S. F., Desai, M. M., Kaouk, J. H., Steinberg, A., Mascha, E. et al: Comparative analysis of laparoscopic versus open partial nephrectomy for renal tumors in 200 patients. J Urol, 170: 64, 2003 4. Rassweiler, J., Seemann, O., Schulze, M., Teber, D., Hatzinger, M. and Frede, T.: Laparoscopic versus open radical prostatectomy: a comparative study at a single institution. J Urol, 169: 1689, 2003 5. Basillote, J. B., Abdelshehid, C., Ahlering, T. E. and Shanberg, A. M.: Laparoscopic assisted radical cystectomy with ileal neobladder: a comparison with the open approach. J Urol, 172: 489, 2004 6. Bishoff, J. T., Allaf, M. E., Kirkels, W., Moore, R. G., Kavoussi, L. R. and Schroder, F.: Laparoscopic bowel injury: incidence and clinical presentation. J Urol, 161: 887, 1999 7. Tan, M., Xu, F. F., Peng, J. S., Li, D. M., Chen, L. H., Lv, B. J. et al: Changes in the level of serum liver enzymes after laparoscopic surgery. World J Gastroenterol, 9: 364, 2003 8. Morino, M., Giraudo, G. and Festa, V.: Alterations in hepatic function during laparoscopic surgery. An experimental clinical study. Surg Endosc, 12: 968, 1998 9. Andrei, V. E., Schein, M., Margolis, M., Rucinski, J. C. and Wise, L.: Liver enzymes are commonly elevated following laparoscopic cholecystectomy: is elevated intra-abdominal pressure the cause? Dig Surg, 15: 256, 1998
Purpose: Presentation of complications following laparoscopic surgery can be different from corresponding open surgical complications. While leukopenia has been identified as a common finding in patients with unrecognized bowel injury following laparoscopy, to our knowledge no study has determined if leukopenia or other serum abnormalities are unique to patients with laparoscopic complications. We present an analysis of postoperative laboratory values from patients after uncomplicated urological laparoscopic surgery. Materials and Methods: A retrospective review of 50 adult patients who had previously undergone uncomplicated laparoscopic urological procedures was performed. Exclusion criteria were preexisting hematological, immune, liver or pancreatic disorders. Common serum laboratory values were measured on postoperative day 1. Results: All values for bilirubin were within normal limits. Of patients undergoing a right side renal procedure, 10 of 16 (63%) had a postoperative increase in liver function tests. Amylase or lipase was increased in a total of 12 (24%) patients. Patients undergoing laparoscopic prostatectomy accounted for the majority of this group with 9 of 21 (43%) patients having increased amylase or lipase. Finally, there were no patients with immediate postoperative leukopenia. Conclusions: Following uncomplicated laparoscopic procedures, bilirubin levels are rarely affected, amylase and lipase may be acutely increased following laparoscopic prostatectomy, and white blood count is commonly increased. While 16 (36%) patients had postoperative leukocytosis, leukopenia was not detected after uncomplicated laparoscopic urological surgery and should alert the surgeon to the possibility of an undiagnosed complication. Key Words: laparoscopy, serum, leukocyte count, amylases, lipase
from 50 patients following uncomplicated urological laparoscopic surgery.
ince the introduction of laparoscopic nephrectomy in 1991,1 laparoscopy has been increasingly used as a treatment modality for several urological diseases. While complication rates from laparoscopic procedures are comparable to those of their open counterparts,2-5 complications obviously occur. More importantly the presentation of these complications can be quite different following laparoscopic vs open procedures. The best studied example is bowel injury. Bishoff et al noted that subjects with bowel injury occurring during laparoscopy did not present with classic peritoneal signs and fever, but instead had trocar site pain, abdominal distention, leukopenia and diarrhea. Of these signs and symptoms leukopenia was quite prominent, occurring in 80% of patients with unrecognized bowel injuries.6 Although laboratory findings such as leukopenia are clearly important in the evaluation for laparoscopic complications, we could find no study following uncomplicated laparoscopy to determine if leukopenia or other serum abnormalities are unique to patients with complications. Thus, we present an analysis of postoperative laboratory values
S
MATERIALS AND METHODS After institutional review board approval, a retrospective review of medical records of 50 patients who had previously undergone uncomplicated laparoscopic urological procedures and had postoperative serum blood work available was performed. These procedures were performed between December 2003 and September 2004. Inclusion criteria were patients undergoing an elective laparoscopic procedure and age greater than 18 years old. Exclusion criteria were preexisting hematological, immune, liver or pancreatic disorder. Patients with intraoperative or postoperative early or late complications, or use of immunosuppressive medication, were also excluded from analysis. Hand assistance was not used in any of the included procedures. Serum laboratory tests were drawn on postoperative day 1 following the respective surgery. Blood work was generally not drawn on subsequent days as there was no clinical indication or the patient was discharged from the hospital. Serum tests consisted of WBC, AST, ALT, GGT, total bilirubin, direct bilirubin, indirect bilirubin, amylase and lipase. Standard laboratory techniques were used to obtain serum values. More specifically WBC and platelet levels were obtained using a cell counter (Coulter® Gen䡠S™ Sys-
Submitted for publication March 7, 2005 Study received institutional review board approval. * Correspondence: Department of Urology, The University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, Texas 75390-9110 (telephone: 214-648-2888; FAX: 214-6488786; e-mail: [email protected]).
0022-5347/06/1751-0167/0 THE JOURNAL OF UROLOGY® Copyright © 2006 by AMERICAN UROLOGICAL ASSOCIATION
167
Vol. 175, 167-169, January 2006 Printed in U.S.A. DOI:10.1016/S0022-5347(05)00045-5
168 SERUM LABORATORY VALUES AFTER UNCOMPLICATED LAPAROSCOPIC UROLOGICAL SURGERY TABLE 1. Patient data by procedure Laparoscopic Procedure
No. Pts (%)
No. Male/Female (%)
No. Rt/Lt (%)
Mean Days Hospital Stay
Prostatectomy Nephrectomy Partial nephrectomy Pyeloplasty Cyst decortication Retroperitoneal lymph node dissection Adrenalectomy
21 (42) 12 (24) 9 (18) 3 (6) 2 (4) 2 (4) 1 (2)
21 (100)/6 (50)/6 (50) 7 (78)/2 (22) 2 (67)/1 (33) 0/2 (100) 2 (100)/0/1 (100)
7 (58)/5 (42) 5 (56)/4 (44) 2 (67)/1 (33) 2 (100)/0 1 (50)/1 (50) 0/1 (100)
1.7 2.6 2.6 2.3 2.0 1.5 3.0
tem 2), and all remaining tests were performed using a chemistry immuno analyzer (Olympus AU400e®). SigmaStat® software was used to perform the chi-square and Mann-Whitney rank sum statistical tests. RESULTS Of the 50 patients included in analysis 38 were male and 12 were female. Mean age was 56 years (range 25 to 75). Laparoscopic procedures included prostatectomy, nephrectomy, pyeloplasty, retroperitoneal lymph node dissection, renal cyst decortication and adrenalectomy. Table 1 shows patient and operative data for each of these procedure groups. Table 2 presents low values, Nl values and increased values for each laboratory test. Increased values are further divided into those increased 1 to 1.5 times, 1.5 to 2 times and greater than 2 times the maximal normal value. Of note, 5 of 6 (83%) and 7 of 8 (88%) patients with increased AST and ALT, respectively, had undergone right side renal procedures. The 2 episodes of increased GGT were following right side renal procedures as well. Thus, of the 16 right side renal procedures performed, 10 (63%) had subsequent increases in AST, ALT or GGT. There was no increase in these liver enzymes following left side renal procedures, and total, direct and indirect bilirubin remained within normal limits regardless of whether the operative site involved the right kidney. Regarding other laboratory tests, increases in amylase and lipase did not correspond to procedures in the left upper quadrant of the abdomen. Instead 9 of 12 (75%) patients with increased amylase or lipase had undergone laparoscopic prostatectomy. This increase in patients who had undergone prostatectomy approached statistical significance (Mann-Whitney rank sum test p ⫽ 0.052) with 9 of 21 (42%) patients having a postoperative increase in amylase or lipase. Thrombocytopenia was a common finding in 10 of 50 (20%) patients but was not correlated with any specific procedure or intraoperative intravenous volume administra-
tion. Estimated blood loss was examined as well, but there was no correlation between this value and the presence of a laboratory abnormality (chi-square test p ⫽ 0.668). Finally and most importantly, while 16 of 50 (32%) patients had postoperative leukocytosis, not a single episode of leukopenia was encountered. DISCUSSION To our knowledge this is the first study to evaluate postoperative laboratory values following uncomplicated laparoscopic urological procedures. We included a variety of laparoscopic procedures for indications ranging from cancer (prostate, renal cell and testis) to renal obstruction (ureteropelvic junction obstruction) to chronic pain (symptomatic renal cysts). The serum laboratory results following these procedures provide a standard for the expected values for an uncomplicated laparoscopic surgery, thus improving interpretation of postoperative laboratory values in patients with suspected complications. After right side renal procedures, increases in AST, ALT and GGT were common. Given the nature of these surgeries, with frequent manipulation of the liver, this comes as little surprise. In fact, increases in these enzymes after laparoscopic cholecystectomy have been well documented.7-9 Their increase after other laparoscopic procedures has also been noted and possibly attributed to carbon dioxide pneumoperitoneum.6,8 On the other hand, bilirubin measurements are infrequently affected by any of the surgeries performed here, thus significant postoperative abnormalities should prompt further investigation. More difficult to explain is the correlation of increased amylase and lipase with laparoscopic prostatectomy. There is no direct manipulation of the pancreas or any surrounding structure during this procedure and pancreatitis is not commonly encountered. In addition, these increases in amylase and lipase are not likely related to prostate surgery itself as neither increase of these enzymes nor pancreatitis is commonly reported following open
TABLE 2. Serum laboratory values following uncomplicated laparoscopic procedures No. (%) Value (NI range)
Below Nl Min
NI
1–1.5 ⫻ Nl
1.5–2 ⫻ Nl
Greater Than 2 ⫻ Nl
WBC (4.1–11 ⫻ 103/ul) Platelets (140–440 ⫻ 103/u/l) Amylase (29–108 U/l) Lipase (7–59 U/l) AST (13–40 U/l) ALT (13–40 U/l) GGT (8–78 U/l) Total bilirubin (0.2–1.3 mg/dl) Direct bilirubin (0.0–0.3 mg/dl) Indirect bilirubin (0.0–0.9 mg/dl)
0 10 (23) 8 (17) 8 (17) 1 (2) 1 (2) 0 0 0 0
29 (64) 33 (77) 34 (71) 31 (65) 41 (86) 39 (82) 40 (93) 46 (100) 39 (93) 33 (100)
11 (25) 0 1 (2) 5 (10) 4 (8) 5 (10) 2 (5) 0 0 0
4 (9) 0 2 (4) 3 (6) 1 (2) 1 (2) 1 (2) 0 1 (2) 0
1 (2) 0 3 (6) 1 (2) 1 (2) 2 (4) 0 0 2 (5) 0
SERUM LABORATORY VALUES AFTER UNCOMPLICATED LAPAROSCOPIC UROLOGICAL SURGERY 169 radical prostatectomy. One possible explanation for this abnormality would be the extreme Trendelenburg position required for the duration of this surgery, but it is not clear how this would lead to the increase in pancreatic enzymes. The final and most important finding was the absence of leukopenia in this patient group. Leukopenia has previously been identified as a common presenting sign of unrecognized bowel injury. This was noted by Bishoff et al after reviewing 915 laparoscopic urological procedures and finding that 4 of the 5 patients with unrecognized bowel perforation had leukopenia.6 The only signs or symptoms that were more prevalent were trocar site pain and abdominal distention, which were present in all 5 patients. It is also important to note that 2 of the 5 patients with unrecognized bowel injuries died secondary to this complication, confirming the significant morbidity/mortality of this complication. As such, postoperative leukopenia is not an expected finding and should raise clinical concerns. Weaknesses of this study include its retrospective design, small sample size and the resulting lack of followup laboratory testing on patients with laboratory abnormalities. Ideally a much larger sample of subjects, powered appropriately and assessed prospectively following a wide variety of procedures, would address this weakness, and give further insight into the significance of increases in amylase and lipase following laparoscopy.
CONCLUSIONS Diagnosis of complications following laparoscopic procedures can be difficult as presentation is often subtle and different from that of open surgery. Our experience suggests that increases in liver and pancreatic enzymes are common but the presence of leukopenia is not encountered following uncomplicated procedures. Thus, the presence of leukopenia should alert the laparoscopic surgeon to the possibility of an unrecognized complication, especially bowel injury.
Abbreviations and Acronyms AST ALT GGT Nl WBC
⫽ ⫽ ⫽ ⫽ ⫽
aspartate aminotransferase alanine aminotransferase ␥-glutamyltransferase normal white blood count
REFERENCES 1. Clayman, R. V., Kavoussi, L. R., Soper, N. J., Dierks, S. M., Meretyk, S., Darcy, M. D. et al: Laparoscopic nephrectomy: initial case report. J Urol, 146: 278, 1991 2. Dunn, M. D., Portis, A. J., Shalhav, A. L., Elbahnasy, A. M., Heidorn, C., McDougall, E. M. et al: Laparoscopic versus open radical nephrectomy: a 9-year experience. J Urol, 164: 1153, 2000 3. Gill, I. S., Matin, S. F., Desai, M. M., Kaouk, J. H., Steinberg, A., Mascha, E. et al: Comparative analysis of laparoscopic versus open partial nephrectomy for renal tumors in 200 patients. J Urol, 170: 64, 2003 4. Rassweiler, J., Seemann, O., Schulze, M., Teber, D., Hatzinger, M. and Frede, T.: Laparoscopic versus open radical prostatectomy: a comparative study at a single institution. J Urol, 169: 1689, 2003 5. Basillote, J. B., Abdelshehid, C., Ahlering, T. E. and Shanberg, A. M.: Laparoscopic assisted radical cystectomy with ileal neobladder: a comparison with the open approach. J Urol, 172: 489, 2004 6. Bishoff, J. T., Allaf, M. E., Kirkels, W., Moore, R. G., Kavoussi, L. R. and Schroder, F.: Laparoscopic bowel injury: incidence and clinical presentation. J Urol, 161: 887, 1999 7. Tan, M., Xu, F. F., Peng, J. S., Li, D. M., Chen, L. H., Lv, B. J. et al: Changes in the level of serum liver enzymes after laparoscopic surgery. World J Gastroenterol, 9: 364, 2003 8. Morino, M., Giraudo, G. and Festa, V.: Alterations in hepatic function during laparoscopic surgery. An experimental clinical study. Surg Endosc, 12: 968, 1998 9. Andrei, V. E., Schein, M., Margolis, M., Rucinski, J. C. and Wise, L.: Liver enzymes are commonly elevated following laparoscopic cholecystectomy: is elevated intra-abdominal pressure the cause? Dig Surg, 15: 256, 1998