Endoscopic Ifb(published In Egja)

Ashraf Abdelbaset and Hisham Soliman: Endoscopic inguinal field block

Endoscopic versus Percutaneous Inguinal Field Block (IFB) for Postoperative Pain Control after Total Extra-Peritoneal (TEP) Inguinal Hernioplasty Ashraf A. Abdelbaset, MD*; Hisham E. Soliman, MD, FRCS† From the Department of Anaesthesiology*, Faculty of Medicine, Ain Shams University and the Department of Surgery†, Faculty of Medicine, Cairo Universioty, Egypt. Address for correspondence: Dr. Ashraf Abdelbaki. Abdelbaset, E-mail: [email protected]

Abstract Background: Despite the proven merits of using inguinal field block in open hernia repair, there is little data examining its use in laparoscopic hernioplasty. Interestingly, complete field block can be approached endoscopically with minimal hazards. The objective of this prospective randomized study was to compare the outcome of two different approaches of inguinal field block (IFB) for postoperative pain control following endoscopic total extra-peritoneal laparoscopic (TEP) inguinal hernioplasty. Methods: Eighty male patients, underwent unilateral endoscopic TEP hernioplasties, were randomized to receive either preoperative percutaneous IFB (group A, n= 40) or intraoperative endoscopic IFB (group B, n=40); using 40 ml of levobupivacaine (0.25%). Postoperative pain was assessed by visual analogue score, VAS on a scale from 0 to 10. The intraoperative anaesthetic requirements, time from end of surgery till extubation, postoperative narcotic analgesia requirement; length of hospital stay and return to full activity were compared between the two groups. Results: A comparison between the two groups showed that patients in group A had significantly less requirements of intraoperative fentanyl analgesia 65.2 (16.8) µg and shorter recovery time 7.3 (1.7) min. than patients in group B 98.4 (27.9) µg and 8.4(2) min. Postoperative pain scores were higher in group A in the first 4-6 hours (p= ns). Postoperative IV morphine requirement was significantly higher in the first 12 hours (Day surgery cases) in group A 13.2 (3) mg than in group B 9.2 (2.5) mg. This difference was not significant among patients hospitalized within the next 24 hours. Almost one third of the patients were able to go home on the same day of surgery (11 in group A and 15 in group B, p= ns). Conclusion: We conclude that inguinal field block for TEP hernioplasty provide merits for the patients regarding the postoperative pain control and short hospital stay. However, endoscopic IFB was shown to have better control of postoperative pain than the percutaneous IFB during the first 12 hours. Key words: Inguinal field block; Levobupivacaine; Laparoscopic hernia repair.

S

everity of pain remains a main outcome parameter in research studies on hernia repair in the era of laparoscopic surgery. Acute pain following total extra-peritoneal laparoscopic (TEP) inguinal hernioplasty is related to skin incisions, peritoneal blunt dissection, overstretched muscles with gas insufflations and use of penetrating clips for mesh fixations to the abdominal muscles, fascia, and ligaments (1). The involvement of the periostium of the pubic bone in the mesh fixation is the probable cause of chronic pain following TEP hernioplasty (2). Extraperitoneal instillation of large volumes of bupivacaine (0.25%) has been shown to be superior to placebo for postoperative analgesia following TEP hernioplasty (3). However, the use of smaller concentrations (0.125%) of bupivacaine, using the same technique did not show any benefits over placebo (4). On the other hand, this technique did not show any added benefits compared to local wound infiltration with small volumes of bupivacaine (5). Dedicated local anaesthesia technique, as the inguinal field block (IFB) described by Sparks and colleagues (6) for open inguinal hernia repair, has shown benefits over general anaesthesia in terms of faster recovery, less pain, better mobilization and higher patient satisfaction (7). Interestingly, during the TEP, the anatomic path of both ilioinguinal and iliohypogastric nerves can be recognized endoscopically with careful reflection of the lateral edge of the pseudo sac. This may allow more accurate nerve blockade from within under direct vision unlike the previously described technique, which is completely blind. This study was designed to test the hypothesis that intraoperative endoscopic inguinal field block, by the surgeon, would provide better and safer postoperative analgesia than preoperative percutaneous block done by the anaesthesiologist.

Patients and methods Eighty male patients undergoing elective endoscopic TEP hernioplasties were included in this study. Patients with bilateral or recurrent hernias, who had allergy or contraindication for use of local anaesthetic drugs, or who are medically compromised (ASA III or more) were excluded from the study. After Ethical Committee approval and written informed consent, patients were randomly assigned by a computer-generated list into two groups: Group A, received percutaneous IFB prior to the surgical procedure and after induction of general anaesthesia by the same

Ashraf Abdelbaset and Hisham Soliman: Endoscopic inguinal field block

anaesthesiologist, and group B, received endoscopic preperitoneal IFB before conclusion of the procedure by the same surgeon. All patients were educated about the operative procedure and its possible risks, the pain assessment process and the available modality of pain control according to the study protocol. On the day of surgery, after establishing IV access, all patients were premedicated with midazolam 2 mg IV 30-45 min before the induction of anaesthesia. General anaesthesia was induced with propofol 1–2 mg/kg and fentanyl 2 µg/kg. Intubation was facilitated with atracurium 0.5 mg/kg and anaesthesia was maintained with sevoflurane 1 MAC end-tidal concentration supplemented with 65% nitrous oxide in oxygen and IV fentanyl as clinically required. Before starting surgery, inguinal field block was performed for patients of group (A) by the same anaesthesiologist using levobupivacaine 0.25 %. A total of 40 ml were injected according to Spark's technique (6). A 22G, 55-mm short-bevel needle was used, with a loss of resistance technique with subsequent recognition of the tissue layers. The first injection site was 2 cm medially from the anterior-superior iliac spine, on a line towards the umbilicus. After the first loss of resistance (LOR) through the external aponeurosis, 7 ml of levobupivacaine was injected. The needle was further advanced to make the second LOR through the aponeurosis of the internal oblique muscle and a further 8 ml was injected. The second injection site was located over the internal inguinal ring, which is 1 cm cranially to the mid-inguinal point. After the second LOR of the needle at this point, 25 ml of levobupivacaine was injected. With the needle perpendicular to the skin, this point is located approximately 4 cm or more from the skin. The endoscopic TEP hernioplasty procedure was carried out according to the standardized technique (8). For patients assigned to group (B), endoscopic recognition of the ilioinguinal and iliohypogastric nerves required more careful lateral dissection of the peritoneum with the aid of the preoperatively localized surface marking of the nerves. Blockage of both nerves was achieved by infiltration of 15 ml of levobupivacaine 0.25 % into the abdominal muscles from within using a laparoscopic needle and another 25 ml were injected around the internal inguinal ring. Finally, a polypropylene mesh was introduced into the pre-peritoneal space through the camera trocar. The mesh was manipulated to cover both the indirect and direct spaces. After conclusion of the surgery the skin incisions were infiltrated with 10 ml of levobupivacaine 0.25% in all cases. All patients were monitored using pulse oximetry, electrocardiography and non-invasive blood pressure recordings; intraand postoperatively. The recovery time was measured from skin closure to extubation. Postoperative pain management was carried out by a professional acute pain service nurse, who was blinded for the used approach of IFB, utilizing a visual analogue scale (VAS) for pain from 0 (no pain) to 10 (very severe pain). Morphine sulphate was given to patients with severe pain (scores ≥6 on VAS) both at rest and on coughing; each bolus contains 0.05 mg/kg body weight. Patients were monitored for: the time to the first analgesia requirement, the total morphine requirements (in 12 and 24 hours) and associated symptoms e.g. nausea and vomiting. Postoperative pain was evaluated on admission to recovery every hour for the first four hours then every 2 hours for the following 12 hours when patients were assessed for time of discharge-to-home readiness according to standard criteria, including: Stable vital signs, ability to void, absence of excessive nausea, pain score 0-2, and ability to dress and walk without support. Accordingly, patients who were ready to go home before 12 hours were considered candidates for day case surgery and were discharged with (NSAID) home medication. Those who were not fitting the criteria or readmitted for narcotic pain control were monitored by the VAS every 4 hours, both at rest and during activity (coughing), until the time of discharge. Statistical analysis Data were recorded for all patients and analyzed using SPSS statistical software. Statistical comparisons were done by independent samples t-test, analysis of variance (ANOVA), and Chi square test for non-numerical data analysis. A P value of less than 0.05 was considered statistically significant.

Results This study was carried out between September 2002 and December 2004 and a total of 80 patients were included. Three patients (two from group A and one from group B) were excluded after conversion of the procedure to the transperitoneal approach due to significant peritoneal tear and gas leakage. The demographic characteristics and hernia type were comparable between the two groups (Table 1). A comparison between the two groups showed no significant difference in the operative, anaesthesia, or recovery time (Table 2). The total supplemental intraoperative fentanyl consumption was significantly less, 65.2 (16.8) mg vs. 98.4 (27.9) mg, in group A and group B, respectively (P< 0.05). The VAS pain scores (0-10) were higher in group A than in group B in the first 4 hours postoperatively (Fig 1), however this was statistically insignificant (P> 0.05). The first postoperative IV morphine analgesia was required earlier in patients of group A, 128 (49) min than in patients of group B, 291 (71) min and this was statistically significant (P< 0.05). The total IV morphine consumption in the first 12 hours was significantly higher in group A than in group B (P<0.05) (Table 3). However, this difference was not detected in patients who required hospitalization for the following 24 hours (P= ns). Comparison of the postoperative morbidity rate between the two groups showed no significant difference (Table 4). Temporary urinary catheterization was required for cases with retention of urine. Only one patient in group B failed to void after removal of the catheter and required urgent transurethral prostatectomy during the same admission. We did not experience any sings of local anaesthesia toxicity such as tinnitus, oral numbness, circumoral pallor, central or cardiovascular manifestations. The mean length of hospital stay for pain control only, based on the time for readiness to go home (Table 5), was 26.6 (13) hours and 25.9 (15.8) hours in groups A and B respectively (P= ns). Only 26 patients (33.8%) were able to go home as day surgery cases, 11 patients in group A and 15 patients in group B (P= NS).

Ashraf Abdelbaset and Hisham Soliman: Endoscopic inguinal field block

Discussion The present study demonstrated that inguinal field block could be adequately achieved by injecting 40 ml of levobupivacaine 0.25% via the laparoscope by the operating surgeon during the TEP hernioplasty with better control of postoperative pain than the percutaneous technique. Hypothetically, optimal pain control could be achieved by the instillation of local anaesthetics into the confined extraperitoneal space. Several studies had been carried out to test this hypothesis but failed to gain consistent results about the benefit of such technique (5, 9, and 10). The problem in this technique is that local anaesthetic instilled in the extraperitoneal space tend to collect over the dependent areas and will not be evenly distributed to block all relevant pain fibers in the field. Preoperative percutaneous IFB was found to provide a high satisfactory intraoperative analgesia, and provides benefits for the patients in terms of faster recovery, less pain, faster mobilization and a higher satisfaction (11). Even isolated block of ilioinguinal and iliohypogastric nerves, was found to provide many of these benefits as for inguinal field block (12, 13). In this study, preoperative percutaneous IFB given at the beginning of the procedure significantly reduce the need for intraoperative narcotic requirement. Yndgaard et al. (14) believed that the deposition of local anaesthetic subfascially is important to improve postoperative pain relief. Interestingly, during the TEP, the anatomic path of both ilioingiunal and iliohypogastric nerves can be recognized endoscopically with careful reflection of the lateral edge of the pseudo sac. This may allow more accurate nerve blockade from within under direct vision unlike the previously described technique that is completely blind. In our study, the endoscopic IFB was found to influence the early postoperative pain score with subsequent delay in the need for strong IV narcotic analgesics, reduced total dose of narcotics needed within the first 12 hours after the operation and reduced incidence of drug related nausea and vomiting. These findings, however, were lacking the strong statistical significance probably due to small sample size. After careful midline search, we could not find any article demonstrating the use of IFB in laparoscopic hernia repair. Both techniques did not show significant influence on the overall length of hospital stay or the late requirement of postoperative narcotic analgesics after the first 12 hours from the end of the operation. Only one third of the cases undergoing endoscopic TEP inguinal hernioplasty were able to leave the hospital within 12 hours as day surgery case. Most of the patients were pain free on discharge from the hospital within 24-36 hours. The local anaesthetic used in this study was levobupivacaine, which is an enantiomer of the racemic bupivacaine because it is less toxic to the CNS and is also less likely to cause myocardial depression and fatal arrhythmias than bupivacaine (15). Levobupivacaine produces a sensory and motor block clinically indistinguishable from that of racemic bupivacaine. However, the duration of sensory block of levobupivacaine is longer than that of bupivacaine (16, 17). This pharmacodynamic profile increase the safety margin of the drug, which can help to do bilateral block in case of bilateral hernia repair. Levobupivacaine was well tolerated in all patients and there were no signs of systemic toxicity. The cardiovascular toxicity was investigated in another study in volunteers after intravenous infusion of both drugs; levobupivacaine resulted in a significantly smaller reduction in stroke index, ejection fraction and acceleration index compared with racemic bupivacaine (18). Overall, both techniques of inguinal field block provide benefits for patients undergoing TEP hernioplasty regarding the postoperative pain control and short hospital stay. However, endoscopic IFB was shown to have better control of postoperative pain than the percutaneous IFB during the first 12 hours.

References 1. 2. 3.

Callesen T, Kehlet H: Postherniorrhaphy pain. Anesthesiology 1997;87:1219-1230. Callesen T, Bech K, Nielsen R, et al: Pain after groin hernia repair. Br J Surg 1998;85:141-144. O’Riordain DS, Kelly P, Horgan PG, et al: A randomized controlled trial of extraperitoneal bupivacaine analgesic in laparoscopic hernia repair. Am J Surg 1998,176:254-257. 4. Saff GN, Marks RA, Kuroda M, et al: Analgesic effect of bupivacaine on extraperitoneal laparoscopic hernia repair. Anesth Analg 1998;87:377-381. 5. Lau H, Patil NG, Lee F, Yeun WK: A prospective trial of analgesia following endoscopic totally extraperitoneal (TEP) inguinal hernioplasty. Local wound infiltration vs extraperitoneal instillation of bupivacaine. Surg Endosc 2002;16:159-162. 6. Sparks CJ, Rudkin GE, Agiomea K. Fa'arondo JR: Inguinal field block for adult inguinal hernia repair using a shortbevel needle. Description and clinical experience in Solomon Islands and an Australian teaching hospital. Anaesth Intensive Care 1995;23:143-148. 7. Aasbo V, Theun , Raeder J: Improved long lasting postoperative analgesia, recovery function and patient satisfaction after inguinal hernia repair with inguinal field block compared with general anesthesia. Act Anaesthesiol Scand 2002;46:674-681. 8. Katkhouda N, Campos GM, Mavor E, Trussler a, Khalil M, and Stoppa R. Laparoscopic Extraperitoneal inguinal hernia repair. A safe approach based on understanding of rectus sheath anatomy. Surg Endosc 1999;13:1243-1246. 9. O’Riordain DS, Kelly P, Horgan PG, et al: A randomized controlled trial of extraperitoneal bupivacaine analgesic in laparoscopic hernia repair. Am J Surg 1998;176: 254- 257. 10. Saff GN, Marks RA, Kuroda M, et al: Analgesic effect of bupivacaine on extraperitoneal laparoscopic hernia repair. Anesth Analg 1998;87:377-381.

Ashraf Abdelbaset and Hisham Soliman: Endoscopic inguinal field block

11. Aaspo A, Thuen A, Raeder J: Improved long-lasting postoperative analgesia-recovery function and patient 12. 13.

14. 15.

16.

satisfaction after inguinal hernia repair with inguinal field block compared with general anesthesia. Acta Anaesthesiol Scand 2002;46:674-678. Harrison CA, Morris S, Harvey JS: Effect of iliinguinal and iliohypogastric nerve block and wound unfiltration with 0.5 % bupivacaine on postoperative pain after hernia repair. Br J Anaesth 1994;72: 691-693. Ding Y, White PF: Postherniorrhaphy pain in outpatient after preincision iliinguinal and iliohypogastric nerve block during monitored anaesthesia care. Can J Anaesth 1995;42:12-15. Yndjaard S, Holst P, Bjerre-Jebsen K: Subcutaneously versus subfascially administered lidocaine in pain treatment after inguinal herniotomy. Anesth Analg 1994;79:324-327. Huang YF, Pryor ME, Mather LE, Veering T: Cardiovascular and central nervous system effects of intravenous levobupivacaine and bupivacaine in sheep. Anesth Analg 1998;86:797-804. De Negri P, Ivani G, Tirri T, Modano P, Reato C, Eksborg S, Lonnqvist PA. A comparison of epidural bupivacaine, levobupivacaine, and ropivacaine on postoperative analgesia and motor blockade.Anesth Analg. 2004;9:45-48.

17. McLeod GA, Burke D. Levobupivacaine. Anaesthesia 2001;56:331-341. 18. Bardsley H, Gristwood R, Baker H, et al: A comparison of the cardiovascular effects of levobupivacaine and rac-bupivacaine following intravenous administration to healthy volunteers. Br J Clin Pharmacol 1998;46:245249. Table 1. Patient characteristics [mean (SD)] Group A (n = 38)

Group B (n = 39)

Age (years) ( SD)

44.9 (11.9)

46.2 (11.3)

Weight (kg) ( SD)

71.2 (9.1)

72.8 (9.6)

Height (cm) ( SD)

166 (6.8)

172 (9)

Direct (%)

15 (39.5%)

18 (46.2%)

Indirect (%)

23 (60.5%)

21 (53.8%)

Right (%)

21 (55.3%)

23 (59%)

Left (%)

17(44.7%)

16 (41%)

Hernia type

Group A: Preoperative Percutaneous IFB, Group B: Intraoperative Endoscopic IFB Table 2. Operative data [mean (SD)] Group A (n = 38)

Group B (n = 39)

Operative time (min)

63.5 (10.6)

67.1 (11.9)

Procedure time (min)

41.7 (8.9)

42.1 ( 8.7)

Recovery time (min)

7.3 (1.7)

8.4 ( 2.1)*

Total fentanyl (µg)

65.2 (16.8)

98.4 ( 27.9)*

Group A: Preoperative Percutaneous IFB, Group B: Intraoperative Endoscopic IFB Operative time= time from induction of general anaesthesia till extubation Procedure time = time from skin incision till closure Recovery time= time from skin closure till extubation * Significantly different from the other group

Ashraf Abdelbaset and Hisham Soliman: Endoscopic inguinal field block

Table 3. Postoperative IV narcotic requirements (morphine sulphate) Group A (n = 38)

Group B (n = 39)

Time of the 1st dose (min)

128 (49)

291 (71)*

Total dose in 12 h (mg)

13.0 (3.0)

9.0 (3.0)*

Total dose in 24 hours (mg)

4.6 (1.8)

4.0 (1.1)

Group A: Preoperative Percutaneous IFB, Group B: Intraoperative Endoscopic IFB * Significantly different from the other group Table 4. Postoperative complications {number (%)) Group A (n = 38)

Group B (n = 39)

Nausea and Vomiting

8 (21.1)

5 (12.8)

Hematomas

7 (18.4)

5 (12.8)

Urinary Retention

2 (5.2)

3 (7.7)

Ileus

0

1 (2.6)

Atelectasis

1 (2.6)

0

Group A: Preoperative Percutaneous IFB, Group B: Intraoperative Endoscopic IFB Table 5. Hospital stay for pain control only Group A (n = 38)

Group B (n = 39)

26.6 (13)

25.9 (15.8)

No Patients (%)

11 (28.9%)

15 (39.5%)

Length of stay (h)

10.7 (1.3) 10.7 (1.3)

9.9 (1.8) 9.9 (1.8)

No of Patients (%)

27 (71.1)

24 (61.5)

Length of stay (h)

33 (9.5)

35.9 (11.7)

Length of stay (h) Day case

Inpatient admissions

Group A: Preoperative Percutaneous IFB, Group B: Intraoperative Endoscopic IFB

Ashraf Abdelbaset and Hisham Soliman: Endoscopic inguinal field block

10

Group A

Visual Analogue Score

9

Group B

8 7 6 5 4 3 2 1

Figure 1. Postoperative Pain Score. Values are means and error bars represent standard deviations Group A: Preoperative Percutaneous IFB, Group B: Intraoperative Endoscopic IFB

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28

ho urs 24

ho urs 20

ho urs 16

ho urs 12

ho urs 10

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6h ou rs

4h ou rs

3h ou rs

2h ou rs

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