World Journal of Colorectal Surgery

: 2020  |  Volume : 9  |  Issue : 1  |  Page : 10--13

Role of local infiltration of methylene blue as an analgesic in stapled hemorrhoidopexy: A prospective study

Pranav Mandovra, Vishakha Kalikar, Prasang Bajaj, Roy Patankar 
 Digestive Disease Centre, Zen Multispecialty Hospital, Mumbai, Maharashtra, India

Correspondence Address:
Dr. Pranav Mandovra
Digestive Disease Centre, Zen Multispecialty Hospital, Plot No. 425, Road No. 10, Chembur, Mumbai - 400 071, Maharashtra


Background: Stapled hemorrhoidopexy gained popularity due to low postoperative pain. Few patients still complain of postoperative anal pain. Methylene blue (MB) in caudal and epidural anesthesia gives long-term pain relief and has also been used to treat intractable pruritus ani. Objective: Evaluate the role of local infiltration of the MB as an analgesic in the procedure for prolapse and hemorrhoids (PPH) surgery. Design: Prospective observational study. Setting: Tertiary health care center. Patients and Methods: Patients with grade-III hemorrhoids were included and were divided into two groups: A and B. Group A received a perianal injection of 2 mL of 1% MB with 10 mL of 25% bupivacaine. Group B received a perianal injection of 2 mL of normal saline with 10 mL of 25% bupivacaine. Main Outcome Measures: Patients were followed up prospectively for pain, hospital stay, and complications. Results were noted and compared between the two groups. Sample Size: 50 patients. Results: Group A had significantly lower pain scores on day 3 (mean ± SD 2.08 ± 1.08) and day 7 (mean ± SD 0.64 ± 0.95) as compared to the pain scores on day 3 (mean ± SD 3.92 ± 1.35) (P-value = 0.000) and day 7 (mean ± SD 2.40 ± 1.0) (P-value = 0.000) in group B. Pain scores within first 24 h and day 21 post-surgery were not statistically significant between groups A and B (P-value = 0.286 and 0.19, respectively). Group B required a significantly higher number of both injectable and oral analgesics (mean + SD 4.03 + 0.94) as compared to group A patients (mean + SD 1.97 + 0.81) (P-value = 0.001). 4% of the patients in group B had prolonged hospital stay due to severe pain. Patients in group A also had a significant reduction in their requirement of analgesics. None of the patients who received MB had any local or systemic allergic reactions. Conclusion: Local infiltration of MB may be used as an effective analgesic in PPH patients without any increase in morbidity. Limitations: Single-center study with a small sample size. Conflict of Interest: None.

How to cite this article:
Mandovra P, Kalikar V, Bajaj P, Patankar R. Role of local infiltration of methylene blue as an analgesic in stapled hemorrhoidopexy: A prospective study.World J Colorectal Surg 2020;9:10-13

How to cite this URL:
Mandovra P, Kalikar V, Bajaj P, Patankar R. Role of local infiltration of methylene blue as an analgesic in stapled hemorrhoidopexy: A prospective study. World J Colorectal Surg [serial online] 2020 [cited 2021 Sep 17 ];9:10-13
Available from:

Full Text


Hemorrhoid sufferers are often afraid of seeking treatment because of hemorrhoidectomy-associated pain. Stapled hemorrhoidopexy, also called procedure for prolapsed hemorrhoids (PPH), is gaining wide popularity due to early return to work and low postoperative pain.[1],[2] Though the pain is significantly less as compared to conventional hemorrhoidectomy, postoperative pain is still a concern in certain patients, further reduction of pain would make this procedure more acceptable. Methylene blue (MB) is used in intractable pruritus ani.[3],[4] Our prospective study evaluates the role of compound methylene blue as an analgesic in PPH surgery.

 Patients and Methods:

This is a single-center observational study conducted from January 2016 to October 2016. All patients presenting to the outpatient with symptomatic grade-III hemorrhoids were identified and were evaluated for surgery. PPH was explained to the patients, and they were counseled. Primary cases aged between 21 and 70 years who had symptomatic third-degree hemorrhoids willing for surgery. Sensitivity to MB dye was tested by injecting 0.1 mL of the dye subcutaneously on the right forearm. Patients who had hemorrhoids associated with other perianal conditions like a fissure-in-ano, fistula-in-ano, patients with allergy to the dye and also male patients with symptoms of prostatism were excluded. Fifty consecutive patients who underwent PPH were included in the study. All surgeries were performed under spinal anesthesia by the same team with the same stapling device and standardized steps. Visual pain scale was explained preoperatively to all patients and they were taught to mark the postoperative pain score on the visual pain scale. Visual analog scale (VAS) ranges between 0 (no pain) and 10 (maximum pain). The pain scorecard was given to each patient to be taken home.

The patients were divided into two groups on the basis of registration number—the even-numbered patients were assigned to group A (study group) and odd-numbered patients were assigned to group B (control group). Group A patients received an injection of 2 mL of 1% MB with 10 mL of 0.25% bupivacaine. Group B patients received an injection of 2 mL of normal saline with 10 mL of 0.25% bupivacaine. 15 cc of the solution was injected in each patient—4 mL was injected subcutaneously in the perianal region, 2 mL in both ischiorectal fossa, and another 4 mL was divided equally and injected posteriorly in the presacral area and anteriorly completing the block as described in simplified easily reproducible pudendal nerve block technique for anorectal surgery (SEPTA).[5] Patients were started on a postoperative high-fiber diet and oral lactulose. Seitz bath was advised to all patients thrice a day.

The statistical comparison between the two groups was carried out using the Chi-square test and the Mann-Whitney test (P < 0.05).

No analgesic was given except diclofenac sodium, which was given on demand—injection for thefirst 24 h and later on as oral tablets. The patients were advised to take a diclofenac tablet for pain when required, and the total number of analgesic tablets taken was recorded during each follow-up. The numbers were compared by the Mann-Whitney test.

Postoperative pain score was measured with the help of a VAS[6] at 6 h, 24 h, 72 h (by telephone), and at 1st and 3rd weeks during the outpatient visit. The pain scores were compared by the Mann-Whitney test. Difficulty in passing urine or urinary retention, pain requiring prolonged stay or unscheduled return, and reaction to MB were recorded and compared.

Approval was taken from the institutional ethical committee for carrying this study.


Pain score

The patients in group A had significantly lower pain scores on days 3 and 7 as compared to group B. The pain score on day 3 in group A was 2.08 ± 1.08 (mean ± SD) and that in group B was 3.92 ± 1.35 (mean ± SD) (P-value = 0.000). The pain score on day 7 in group A was 0.64 ± 0.95 (mean ± SD) and that in group B was 2.40 ± 1.0 (mean ± SD) (P-value = 0.000). Pain scores within thefirst 24 h and on day 21 post-surgery were statistically not significant. The pain score in group A within thefirst 24 h was 4.40 ± 1.15 (mean ± SD) and that in group B was 5.20 ± 1.15 (mean ± SD) (P-value = 0.286). Pain score on day 21 post-surgery in group A was 0.32 ± 0.75 (mean ± SD) and in group B was 0.64 ± 0.95 (P-value 0.19) [Table 1] and [Figure 1].{Table 1}{Figure 1}

Total number of analgesics taken by the patients—injectable and oral diclofenac

Group B patients required a significantly higher number of both injectable and oral analgesics (mean ± SD 4.03 ± 0.94) as compared to group A patients (mean ± SD 1.97 ± 0.81) (P-value = 0.0001). Though there is no significant difference in pain scores between the two groups on days 1 and 21, group B patients had consumed a significantly higher number of analgesics on day 1 (P-value = 0.008) and between days 7 and 21 (P-value = 0.000) [Table 2] and [Figure 2].{Table 2}{Figure 2}

Difficulty in passing urine or urinary retention

Difficulty in passing urine was recorded and compared by the Chi-square test. Six out of 25 (24%) patients in group A had difficulty in passing urine and 4 out of 25 patients (16%) in group B had the same difficulty. This difference was not statistically significant, with no urinary retention requiring catheterization [Table 3].{Table 3}

Pain requiring prolonged stay or unscheduled return

All the patients were routinely discharged 24 h after surgery. Only one group B patient (4%) had to stay for 48 h because of pain.

Reaction to methylene blue

None of the patients had any kind of reaction to MB.


PPH involves the removal of abnormally enlarged mucosal tissue, followed by a repositioning of the remaining hemorrhoidal tissue back to its normal anatomical position. This procedure avoids sensitive perianal area wounds and has significantly lowered postoperative pain.[2] However, it still causes significant postoperative pain in 10–30% of patients and some also develop persistent severe pain.[7],[8]

Pain following PPH surgery is less in the early postoperative period,[9],[10],[11] it might be because of low staple line in the sensitive upper anal canal or lower rectum which may be due to purse-string suture taken in close proximity to the dentate line.[12] Chronic pain after PPH rates from 1.6% to 31%[13],[14] and is attributed to fibrosis around the retained staples or incorporation of smooth muscles in the doughnut,[15] triggering the somatic nerve endings at the level of the puborectalis muscle and of the levator ani[16] Agrapphectomy, the removal of the staple line and manually refashioning the anastomosis, has been advocated by Wunderlich et al. for chronic pain following PPH.[17]

The use of the compound MB in caudal and epidural anesthesia gives long-term pain relief.[18],[19],[20] It is also used for the treatment of intractable and severe pruritus ani.[3],[4] MB acts on glucose metabolism and alters membrane potential and acid-base balance and, hence, trapping injected local anesthetic by prolonging its effect.[20] This prospective randomized study evaluates the efficacy of MB injection on post-PPH pain.

Postoperative pain reduction was observed between days 1 and 7 in patients who had the MB injection. These patients also required a lesser dose of analgesics and none had severe or prolonged pain. Sim et al.[21] found similar results following open hemorrhoidectomy by perianal intradermal MB injection.

There had been some discoloration of perianal skin during the initial 7–10 days, however, at 3 weeks, it vanished. MB injection can augment the beneficial effects of PPH by obliterating the severe pain that is sometimes associated with this procedure making the procedure more acceptable to surgeons and patients.

The results showed benefit in a group of patients using a simple, safe, and easily reproducible technique. Further studies with larger sample sizes are required to validate the results of this study.

Financial support and sponsorship


Conflicts of interest

There are no conflicts of interest.


1Mehigan BJ, Monson JRT, Hartley JE. Stapling procedure for haemorrhoids versus Milligan Morgan haemorrhoidectomy: Randomized controlled trial. Lancet 200;335:784-5.
2Rowsell M, Bello M, Hemingway DM. Circumferential mucosectomy (stapled haemorrhoidectomy) versus conventional haemorrhoidectomy; randomized controlled trial. Lancet 2000;355:779-1.
3Mentes BB, Akin M, Leventoglu S, Gultekin FA, Oguz M. Intradermal methylene blue injection for the treatment of intractable idiopathic pruritus ani: Results of 30 cases. Tech Coloproctol 20041;8:11-4.
4Sutherland AD, Faragher IG, Frizelle FA. Intradermal injection of methylene blue for the treatment of refractory pruritus ani. Colorectal Dis 2009;11:282-7.
5Ladha A, Garg P, Puranik C. Simplified easily reproducible pudendal nerve block technique for anorectal surgery (SEPTA)-a video vignette. Colorectal Dis 2018;20:829.
6Dixon JS, Bird HA. Reproducibility along a 10 cm vertical visual analogue scale. Ann Rheum Dis 1981;40:87-9.
7Racalbuto A, Aliotta I, Corsaro G, Lanteri R, Di Cataldo A, Licata A. Hemorrhoidal stapled prolapsectomy vs. Milligan Morgan hemorrhoidectomy: A long-term randomized trial. Int J Colorectal Dis 2004;19:239-44.
8Boccasanta P, Capretti PG, Venturi M, Cioffi U, De Simone M, Salamina G, et al. Randomised controlled trial between stapled circumferential mucosectomy and conventional circular hemorrhoidectomy in advanced hemorrhoids with external mucosal prolapse. Am J Sur 2001;182:64-8.
9Gravie JF, Lehur PA, Huten N, Papillon M, Fantoli M, Descottes B, et al. Stapled hemorrhoidopexy versus Milligan-Morgan hemorrhoidectomy: A prospective, randomized, multicenter trial with 2- year postoperative follow-up. Ann Surg 2005;242:29-35.
10Palimento D, Picchio M, Attanasio U, Lombardi A, Bambini C, Renda A. Stapled and open hemorrhoidectomy: Randomized controlled trial of early results. World J Surg 2003;27:203-7.
11Correa-Rovelo JM, Tellez O, Obregon L, Miranda-Gomez A, Moran S. Stapled rectal mucosectomy vs. closed hemorrhoidectomy: A randomized, clinical trial. Dis Colon Rectum 2002;45:1367-74.
12Correa-Rovelo JM, Tellez O, Obregón L, Duque-López X, Miranda-Gómez A, Pichardo-Bahena R, et al. Prospective study of factors affecting postoperative pain and symptom persistence after stapled rectal mucosectomy for hemorrhoids: A need for preservation of squamous epithelium. Dis Colon Rectum 2003;46:955-62.
13Thaha MA, Irvine LA, Steele RJ, Campbell KL. Postdefecation pain syndrome after circular stapled anopexy is abolished by oral nifedipine. Br J Surg 2005;92:208-10.
14Ortiz H, Marzo J, Armendariz P, De Miguel M. Stapled hemorrhoidopexy vs. diathermy excision for fourth-degree hemorrhoids: A randomized, clinical trial and review of the literature. Dis Colon Rectum 2005;48:809-15.
15Cheetham MJ, Mortensen NJ, Nystrom PO, Kamm MA, Phillips RK. Persistent pain and fecal urgency after stapled haemorrhoidectomy. Lancet 2000;356:730-3.
16Brusciano L, Ayabaca SM, Pescatori M, Accarpio GM, Dodi G, Cavallari F, et al. Reinterventions after complicated and failed stapled haemorrhoidopexy. Dis Colon Rectum 2004;47:1846-51.
17Wunderlich M, Freitas A, Langmayr J, Lechner M, Tentschert G. Anal incontinence after hemorrhoidectomy. J UrolUrogynakol 2004;11:31-3.
18Yang Z, Tianyu Z, Wei Z, et al. Caudal anesthesia in anorectal surgery [J]. China Anorectal J 2008;28:43.
19Donghui Z, Bo S, Yujie Z. Tetracaine combined with compound methylene blue for anal disease clinical observation of postoperative pain [J]. Shanxi Med J 2008;37:1434.
20Leong S, Qinghui M, Chang L. Methylene blue long-acting analgesic compound mixed hemorrhoid pain for clinical research [J]. China Anorectal J 2003.
21Sim HL, Tan KY. Randomized single-blind clinical trial of intradermal methylene blue on pain reduction after open diathermy haemorrhoidectomy. Colorectal Dis 2014;16:O283-7.