Comparison of ilioinguinal-iliohypogastric nerve block versus spinal anesthesia for inguinal herniorrhaphy.

Objective: This study was carried out to determine the optimal anesthetic technique for use in elective herniorrhaphy.

Methods: We retrospectively analyzed 126 inguinal hernia repairs. The patients were allocated to one of two groups: an ilioinguinal-iliohypogastric nerve block group (IHNB group, n = 63) and spinal anesthesia group (SA group, n = 63). We recorded information about perioperative and postoperative parameters.

Results: There were statistically significant decreases in both mean arterial pressure and pulse rate in the SA group (P < 0.001). None of the patients in the IHNB group required recovery room care. Patients in the IHNB group initiated oral intake (0.31 [+ or -] 0.1 h) more quickly than patients in the SA group (5.74 [+ or -] 0.1 h) (P < 0.001). The time-to-home readiness was significantly lower (14.1 [+ or -] 1.5h) in group IHNB, compared with group SA (42.8 [+ or -] 5.3h) (P < 0.001). First rescue analgesic time postoperatively was 3.30 [+ or -] 0.2 hours in group SA and 2.7 [+ or -] 0.13 hours in group IHNB (P < 0.05).

Conclusion: The use of IHNB for patients undergoing herniorrhaphy resulted in a shorter time-to-home readiness, quicker oral intake post surgery, and no need for recovery room care, when compared with the use of SA.

Key Words: ilioinguinal-iliohypogastric nerve block, spinal anesthesia, herniorrhaphy

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Hernia repair is one of the most common operations performed in general surgery. (1) In the absence of established protocols, the choice of anesthetic technique in patients undergoing elective inguinal herniorrhaphy is often somewhat arbitrary. Moreover, many anesthesiologists prefer to use spinal or general anesthesia in patients undergoing herniorrhaphy. Spinal anesthesia (SA) can lead to adverse effects: headache, urinary retention, motor block of lower extremities, intraoperative hypotension, delayed mobility and release from the hospital, etc. On the other hand, peripheral block does not lead to those adverse effects. But peripheral block, such as ilioinguinal-iliohypogastric nerve block (IHNB), is generally used for postoperative analgesia after herniorrhaphy. (2-5) This study was carried out to determine whether the choice of SA or IHNB in elective herniorrhaphy surgery affects intraoperative and postoperative parameters.

Materials and Methods

A retrospective chart review identified 126 consecutive patients, ages 19 to 90, who underwent unilateral inguinal herniorrhaphy between 1999 and 2002. Exclusion criteria were cardiovascular, respiratory, or renal/hepatic problems, metabolic disease, active gastrointestinal reflux, mental dysfunction, and morbid obesity. ASA (American Society of Anaesthesiologists) I-II-III patients (ASA I: A normal healthy patient, ASA II: A patient with mild systemic disease and no functional limitations, ASA III: A patient with moderate to severe systemic disease that results in some functional limitation) were allocated to one of two groups: an ilioinguinal/iliohypogastric nerve block group (group IHNB, n = 63) and spinal anesthesia group (group SA, n = 63). Premedication consisted of diazepam (2 mg) given orally in the evening. Each patient was monitored in the operation room using an electrocardiograph, a pressure cuff and an oxygen saturation probe. In all cases, administration of lactated Ringer's solution (50 mL/h) was begun in the operating room before the anesthetic was given, and was continued postoperatively for 4 to 6 hours. Patients received IV sedation with small doses of midazolam (1 mg) as necessary for maximum comfort. IHNBs were performed using 6 mL of bupivacaine (0.25%) with subsequent infiltration of the skin 1/2 inch medially and 1/2 inch inferiorly to the anterior superior iliac spine, as well as the deeper layers with about 40 mL of bupivacaine 0.25% with a 22-gauge spinal needle. In the SA group, patients were administered spinal anesthesia using the midline approach with a 25-gauge Whitacre needle at the L3-4 or L4-5 intervertebral space with the patient in the lateral decubitus position. The subarachnoid injection contained 3 mL of heavy bupivacaine (0.5%). Sensory block was assessed by loss of pinprick sensation at T12. The operations were performed either by a staff surgeon or by a resident surgeon, with a staff surgeon acting as teaching assistant. The hernia repairs were done with use of Liechtenstein mesh repair. Postoperatively the patients were given meperidine as needed for pain. We recorded the following covariables: patient's age, gender, ASA physical status, type of hernia, type and time of surgery, mean arterial blood pressure and pulse rate before and after the anesthetic techniques, the time of first oral intake after surgery (the time until oral intake in the surgical ward), the time-to-home readiness (meeting the criteria for discharge home from the day surgery unit), and the first rescue analgesic time (the time until administration of the first supplemental analgesia in the surgical ward).

Data are presented as means [+ or -] standard deviation (SD). Statistical analysis was performed using Independent Samples test, Mann-Whitney U test, Wilcoxon Signed Ranks test, Pearson [chi square] test, and Fisher's exact test. Statistical significance was considered as P < 0.05.

Results

There were no statistically significant differences among the two anesthetic technique groups with respect to demographic characteristics (age, gender, ASA physical status), type of hernia, or type and duration of surgery (Table 1).

The values of mean arterial blood pressure and pulse rate before and after the anesthetic techniques are shown in Table 2. We found a significant decrease in both mean arterial blood pressure and pulse rate in the spinal anesthesia group (P < 0.001) (Table 2). Adjuvant medication was given in 11 (17.4%) and 10 (15.8%) patients in the IHNB group and the SA group, respectively. Two patients in the IHNB group and one patient in the SA group were converted to general anesthesia because of severe pain during dissection. None of the patients in the IHNB group required recovery room care. Patients in the IHNB group initiated oral intake (0.31 [+ or -] 0.1 h) more quickly than patients in the SA group (5.74 [+ or -] 0.1 h) (P < 0.001). The time-to-home readiness was significantly lower (14.1 [+ or -] 1.5 h) in the IHNB group compared with the SA group (42.8 [+ or -] 5.3 h) (P < 0.001). First rescue analgesia time postoperatively was 3.30 [+ or -] 0.2 hours in the SA group and 2.7 [+ or -] 0.13 hours in the IHNB group (P < 0.05) (Table 2). There were no perioperative or postoperative complications.

Discussion

Ilioinguinal-iliohypogastric nerve block is widely used for postoperative pain relief after inguinal herniorrhaphy because it is free of many side effects, such as motor block of the lower limbs and urinary retention. (2) However, it is not an easy technique to perform, because of anatomic variation of ilioinguinal and iliohypogastric nerves. (6) In addition, IHNB is rarely used for intraoperative anesthesia. (3) The postoperative analgesic effect of this technique in children has been demonstrated in several studies. (7-9) On the other hand, spinal anesthesia is widely used for inguinal herniorrhaphy. (10) This study compared the effect of two different anesthetic techniques on perioperative and postoperative parameters. We found a significant decrease in both mean arterial blood pressure and pulse rate in the spinal anesthesia group, when compared with preoperative values. In addition, these parameters were significantly reduced perioperatively in the SA group compared with the IHNB group. This study demonstrates that the use of IHNB for inguinal herniorrhaphy provides significant advantages over the spinal anesthesia, including shorter time-to-home readiness and faster initial oral intake.

Inguinal herniorrhaphy is unfortunately associated with a high incidence (29%) of postoperative chronic pain. (11) Inguinal neuralgia is one of the most common complications following inguinal hernia repair. (12) Our study showed a statistically significant decrease in the first rescue analgesia time in the IHNB group. But, on the other hand, there were statistically significant faster initial oral intakes and shorter times-to-home readiness demonstrated in the IHNB group patients, compared with the SA group patients. In addition, none of the IHNB patients required time in the recovery room

In centers with a special interest in open hernia surgery, local anesthesia has been used extensively with excellent outcomes. (13) General anesthesia remains the technique of choice for uncooperative or anxious patients, difficult repairs (reoperation after a mesh repair), or when a local anesthetic technique fails to provide adequate surgical conditions. (14) In our study, two patients in both the IHNB and SA groups required conversion to general anesthesia for completion of the procedure.

Postanesthetic care is usually indicated until the effects of general or spinal anesthesia, including cerebral, cardiovascular, and pulmonary effects, have abated. With the IHNB technique, these organ systems were unaffected, thus eliminating the stay in a recovery unit. In our study, none of the patients in the IHNB group required recovery room care.

Kark et al (13) have suggested that the major advantages of herniorrhaphy under local anesthesia were simplicity, substantial cost savings and very low rates of complications. In our study, patients in the IHNB group had faster times to initial oral intake than patients in the SA group, and the time-to-home readiness was significantly lower in the IHNB group compared with the SA group. Perioperative and postoperative complications did not occur in either group.

The choice of anesthetic technique in patients undergoing elective inguinal herniorrhaphy is often somewhat arbitrary. However, our results suggest that the perioperative and the postoperative parameters in patients undergoing elective inguinal herniorrhaphy may depend in part on the choice of anesthetic technique.

Conclusion

In summary, ilioinguinal-hypogastric nerve block technique would appear to offer advantages over spinal anesthesia technique for the inguinal herniorrhaphy procedure. These advantages include shorter initial oral intake time and shorter time-to-home readiness.

Acknowledgments

We would like to thank Dr. Paul Kretchmer ([e-mail]) at San Francisco Edit for his assistance in editing this manuscript.

References

1. Hair A, Duffy J, McLean J, et al. Groin hernia repair in Scotland. Br J Surg 2000:87:1722-1726.

2. Petros JG, Rimm EB, Robillard RJ, et al. Factors influencing postoperative urinary retention in patients undergoing elective inguinal herniorrhaphy. Am J Surg 1991;161:431-433.

3. Houck CS, Troshynski T, Berde CB. Treatment of pain in children. In Wall PD, Melzack R (eds): Textbook of Pain, Chureill Livingstone, Edinburgh, London, Madrid, 1994, 3rd ed, pp 1419-1437.

4. Broadman LM, Jo Rice L. Neural Blockade for pediatric surgery. In Cousins MJ, Bridenbaugh PO (eds): Neural Blockade. Lippincott-Raven, Philadelphia, New York, 1998, 3rd ed, pp 615-639.

5. Callesen T, Bech K, Kehlet H. One-thousand consecutive inguinal hernia repairs under unmonitored local anesthesia. Anesth Analg 2001;93:1373-1376.

6. McVay A. Surgical Anatomy. Vol 1. Saunders Company, 5th ed, 1971, pp 475-479.

7. Shimoda T, Sasaoka N, Yamaguchi A, et al. Ilioinguinal/iliohypogastric nerve block for pediatric inguinal herniorrhaphy; evaluation of the dose of ropivacaine. Masui 2004;53:1259-1262.

8. Sasaoka N, Kawaguchi M, Yoshitani K, et al. Evaluation of genitofemoral nerve block, in addition to ilioinguinal and iliohypogastric nerve block, during inguinal hernia repair in children. Br J Anaesth 2005;94:243-246.

9. Tsuchiya N, Ichizawa M, Yoshikawa Y, et al. Comparison of ropivacaine with bupivacaine and lidocaine for ilioinguinal block after ambulatory inguinal hernia repair in children. Paediatr Anaesth 2004;14:468-470.

10. Sueda LAA, Liu SS. Centroneuraxial blockade for ambulatory surgery, In Steele SM, Nielsen KC, Klein SM (eds): Ambulatory Anesthesia, Perioperative Analgesia. McGraw-Hill, New York, 2005, pp 335-345.

11. Bay-Nielsen M, Perkins FM, Kehlet H. Pain and functional impairment 1 year after inguinal herniorrhaphy: a nationwide questionnaire study. Ann Surg 2001;233:1-7.

12. Dittrick GW, Ridl K, Kuhn JA, et al. Routine ilioinguinal nerve excision in inguinal hernia repairs. Am J Surg 2004;188:736-740.

13. Kark AE, Kurzer M, Waters KJ. Tension-free mesh hernia repair: review of 1098 cese local anesthesia in a day unit. Ann R Coll Surg Engl 1995;77:299-304.

14. Schumpelick V, Treutner KH, Arlt G. Inguinal hernia repair in adults. Lancet 1994;344:375-339.</p> <pre> Nature has never read the Declaration of Independence. It continues to make us unequal --Will Durant </pre> <p>Aysun Yilmazlar, MD, Halil Bilgel, MD, Canan Donmez, MD, Ayla Guney, MD, Tuncay Yilmazlar, MD, and Oguz Tokat, MD

From Departments of Anesthesiology and General Surgery, Uludag University Medical School, Bursa, Turkey.

Reprint requests to Associate Professor, Dr. Aysun Yilmazlar, Uludag University Medical School, Department of Anesthesiology, Bursa, Turkey. Email: [e-mail]

We do not have any financial support or proprietary statements to declare with relation to this study.

Accepted September 15, 2005.

RELATED ARTICLE: Key Points

* Hernia repair is one of the most common operations performed in general surgery.

* Spinal anesthesia or ilioinguinal-iliohypogastric nerve block may affect intraoperative and postoperative parameters in herniorrhaphy surgery.

* Ilioinguinal-iliohypogastric nerve block technique would appear to offer advantages over the spinal anesthesia technique.

Table 1. Patients' demographic characteristics, type of hernia, type and
time of surgery for ilioinguinal/iliohypogastric nerve block (IHNB) and
spinal anesthesia (SA) for inguinal herniorrhaphy procedures (mean
[+ or -] SD)

                                Group IHNB         Group SA

Number (n)                      63                 63
Age (yr)                        60.1 [+ or -] 2.3  55.5 [+ or -] 1.7
Gender (M/F)                    51/12              55/8
ASA physical status (I/II/III)  32/15/16           28/15/20
Type of hernia                  51/12              55/8
  (primary/recurrent)
Type of surgery                 63                 63
  (Lichtenstein repairs)
Time of surgery (min)           86 [+ or -] 20     92 [+ or -] 17

Table 2. Mean arterial pressure, heart rate values, and postoperative
parameters in the ilioinguinal/iliohypogastric nerve block (IHNB) group
and spinal anesthesia (SA) group before and after the techniques (mean
[+ or -] SD)

                                Group IHNB          Group SA
                                (n = 63)            (n = 63)

Mean arterial pressure (mm Hg)
Before the technique            72.3 [+ or -] 12.3  70.3 [+ or -] 10.3
After the technique             70.3 [+ or -] 11.1  52.3 [+ or -] 9.3*
Pulse rate (beats/min)
Before the technique            77.0 [+ or -] 0.8   78.0 [+ or -] 1.7
After the technique             80.7 [+ or -] 0.9   69.5 [+ or -] 1.8*
Adjuvant medication (n) (%)     11 (17.4%)          10 (15.8%)
Conversion to general            2 (3.1%)            1 (1.5%)
  anesthesia (n) (%)
Time to oral intake (h)          0.3 [+ or -] 0.1*   5.7 [+ or -] 0.1
Time-to-home readiness (h)      14.1 [+ or -] 1.5*  42.8 [+ or -] 5.3
First rescue analgesic           2.7 [+ or -] 0.1    3.3 [+ or -] 0.2**
  time (h)

*P < 0.001
**P < 0.05