[Anorectal and perineal pain]. / Anorektale und perineale Schmerzen.

Anorectal and perineal pain Abstract. Anorectal pain is a common clinical challenge in the outpatient office. Anal fissures, anal venous thrombosis, proctitis or neoplasms are frequent etiologies for proctalgia. After exclusion of somatic disorders by diagnostic imaging and endoscopy, functional anorectal pain or pathologies like interstitial cystitits, chronic prostatitis, coccycodynia or pudendal neuralgia should be considered. The Rome IV criteria distinguish proctalgia fugax, a sharp paroxysmal pain lasting for maximum 30 minutes, and the levator ani syndrom. Latter is characterized by a tender puborectal muscle on digital rectal examination and pain lasting for more than 30 minutes. Treatment consists in reassurance, sitz bathes, topical vasodilators and anal massage. Biofeedback is a further option for levator ani syndrome. Painful palpation of the ox coccygis leads to the diagnosis of coccycodynia, a non-functional disorder. Therapy consists in anti-inflammatory medications, os coccygis mobilisation and infiltration therapy. Urologic chronic pelvic pain (chronic prostatitis and interstitial cystitis) as well as pudendal neuralgia, both neurogenic pelvic pain syndromes, can cause pain radiating into the after and perineum. The diagnosis and discrimination from functional rectal pain is difficult. Patients with neurogenic anorectal pain are best treated with anti-inflammatory medications, pain modulating antidepressives, anticonvulsives or local infiltration therapy. Interdisciplinary management of complex pain patients is mandatory.

Supplemental oxygen, but not supplemental crystalloid fluid, increases tissue oxygen tension in healthy and anastomotic colon in pigs.

BACKGROUND: Low tissue oxygen tension is an important factor leading to the development of wound dehiscence and anastomotic leakage after colon surgery. We tested whether supplemental fluid and supplemental oxygen can increase tissue oxygen tension in healthy and injured, perianastomotic, and anastomotic colon in an acutely instrumented pig model of anastomosis surgery. METHODS: Sixteen Swiss Landrace pigs were anesthetized (isoflurane 0.8%-1%) and their lungs ventilated. The animals were randomly assigned to low fluid treatment ("low" group, 3 mL x kg(-1) x h(-1) lactated Ringer's solution) or high fluid treatment ("high" group, 10 mL/kg bolus, 18 mL x kg(-1) x h(-1) lactated Ringer's solution) during colon anastomosis surgery and a subsequent measurement period (4 h). Two-and-half hours after surgery, tissue oxygen tension was recorded for 30 min during ventilation with 30% oxygen. Three hours after surgery, the animals' lungs were ventilated with 100% oxygen for 60 min. Tissue oxygen tension was recorded in the last 30 min. Tissue oxygen tension was measured with polarographic Clark-type electrodes, positioned in healthy colonic wall, close (2 cm) to the anastomosis, and in the anastomosis. RESULTS: In every group, tissue oxygen tension during ventilation with 100% oxygen was approximately twice as high as during ventilation with 30% oxygen, a statistically significant result. High or low volume crystalloid fluid treatment had no effect on colon tissue oxygen tension. CONCLUSIONS: Supplemental oxygen, but not supplemental crystalloid fluid, increased tissue oxygen tension in healthy, perianastomotic, and anastomotic colon tissue.

Mild hypercapnia increases subcutaneous and colonic oxygen tension in patients given 80% inspired oxygen during abdominal surgery.

BACKGROUND: Supplemental perioperative oxygen increases tissue oxygen tension and decreases incidence of wound infection in colorectal surgery patients. Mild intraoperative hypercapnia also increases subcutaneous tissue oxygen tension. However, the effect of hypercapnia in patients already receiving supplemental oxygen is unknown, as is the effect of mild hypercapnia on intestinal oxygenation in humans-although the intestines are presumably the tissue of interest for colon surgeries. The authors tested the hypothesis that mild intraoperative hypercapnia increases both subcutaneous tissue and intramural intestinal oxygen tension in patients given supplemental oxygen. METHODS: Patients undergoing elective colon resection were randomly assigned to normocapnia (n = 15, end-tidal carbon dioxide tension 35 mmHg) or mild hypercapnia (n = 15, end-tidal carbon dioxide tension 50 mmHg). Intraoperative inspired oxygen concentration was 80%. The authors measured subcutaneous tissue oxygen tension in the right upper arm and intramural oxygen tension in the left colon. Measurements were averaged over time within each patient and, subsequently, among patients. Data were compared with chi-square, unpaired t, or Mann-Whitney rank sum tests; P < 0.05 was significant. RESULTS: Morphometric characteristics and other possible confounding factors were similar in the groups. Intraoperative tissue oxygen tension in hypercapnic patients was significantly greater in the arm (mean +/- SD: 116 +/- 29 mmHg vs. 84 +/- 25 mmHg; P = 0.006) and colon (median [interquartile range]: 107 [81-129] vs. 53 [41-104] mmHg; P = 0.020). CONCLUSIONS: During supplemental oxygen administration, mild intraoperative hypercapnia increased tissue oxygen tension in the arm and colon. Previous work suggests that improved tissue oxygenation will reduce infection risk via the proposed pathomechanism, although only an outcome study can confirm this.