Resting anal pressure following hemorrhoidectomy and lateral sphincterotomy

The role of high anal pressure in the pathophysiology of hemorrhoids and anal fissures is debated. We compared resting anal pressures following left lateral sphincterotomy and hemorrhoidectomy in a prospective manometric study with emphasis on the recovery of the internal anal sphincter activity.

Included in the study were 38 patients with third-degree or fourth-degree symptomatic hemorrhoids who underwent hemorrhoidectomy, 50 patients with anal fissure who underwent sphincterotomy, and 12 healthy patients who served as controls. All patients with anal fissure or hemorrhoids underwent periodic manometric evaluation: 1 month before surgery and 1, 3, 6, and 12 months after surgery. The control group had three manometric evaluations 6 months apart.

Baseline pressure measurement in the fissure group was significantly higher than in the hemorrhoid group, which was significantly higher than in the control group (138 +/- 28.4 mmHg vs. 108.4 +/- 23 mmHg vs. 73 +/- 5.9 mmHg, P < 0.0001). Twelve months after surgery, anal resting pressure remained significantly lower than the baseline measurements in both the fissure (110 +/- 18.2 vs. 138 +/- 28.4, P < 0.0001) and hemorrhoid groups (103.6 +/- 21.5 vs. 108 +/- 23, P < 0.0001), but both remained higher than the control group (103.6 +/- 21.5 mmHg vs. 73 +/- 5.9 mmHg, P < 0.0001).

Resting pressure is elevated in hemorrhoid and anal fissure patients. After surgery the anal resting pressure is reduced but is still higher than in the control group. Further studies are required to investigate the protective effect of postsurgical reduction of anal resting pressure against recurrence.