Ali Ozer,1 Aysun Yilmazlar,2 Ersin Oztürk,1 Tuncay Yilmazlar1 1Department of General Surgery, 2Department of Anesthesiology and Reanimation, Faculty of Medicine, Uludag University, Görükle, Turkey Background: In a previous prospective randomized trial, we showed that local anesthetic infusion using a preperitoneal catheter is an effective postoperative analgesic method following colorectal resections. Over time, we have improved the technique of preperitoneal catheter analgesia. In this prospective cohort study, we report the results of 100 consecutive patients who underwent colorectal resections. Materials and methods: Preperitoneal catheter analgesia was performed via a multihole catheter placed in the preperitoneal space using 10 mL 0.5% levobupivacaine every 4 hours following the operation for the first 3 days. Additional analgesics were used whenever necessary. Postoperative pain was assessed with the visual analog scale score. Short-term clinical outcomes, such as need for systemic analgesics, time to first gas and stool discharge, length of hospital stay, and morbidity, particularly surgical site infections, were reported. Results: From May 2009 to May 2010, 100 consecutive patients were recruited in the study. A total of 83 patients were operated on for malignancy, and the tumor was located in the rectum in 52 patients and in the colon in 31 patients. The median pain score was 4 (0–6), 3 (0–9), 2 (0–8), 1 (0–8), 1 (0–6), 0 (0–6), and 0 (0–3) at postoperative hours 0, 1, 4, 12, 24, 48, and 72, respectively. Additional analgesics were required in 34 patients: 21 of them required only nonsteroidal anti-inflammatory drugs, and 13 patients needed opioids additionally. The median amounts of opioid analgesics and nonsteroidal anti-inflammatory drugs were 1.76±0.78 mg and 6.70±1.18 mg, respectively. However, almost all of the additional analgesics were given in the first 24 hours. Surgical site infections were detected in eight patients. Conclusion: Preperitoneal catheter analgesia is an effective analgesic method. When applied and used properly, it may even be used as the sole analgesic method in some patients. Keywords: preperitoneal, colorectal, analgesia