Final answer:
The choice of drain following a Hartman's procedure for sigmoid diverticular disease with pericolic abscess and colovesical fistula ranges from a Redivac drain to potentially no drain, based on the surgeon's discretion and the specifics of the case.
Step-by-step explanation:
The appropriate type of drain to insert following a Hartman's procedure, particularly in the case of diverticular disease with pericolic abscess and colovesical fistula, is not universally agreed upon; however, the use of a Redivac drain (option c) can be considered. The Redivac drain is a type of closed suction drain which is commonly used after abdominal surgeries to prevent accumulation of fluids or blood and reduce the risk of infection. Keeping the surgical site dry helps with healing and prevents complications. Although historically drains were frequently used, the trend in modern surgery is towards selective rather than routine drainage. Therefore, if the abscess has been cleared and no ongoing leakage is expected, it might be possible to opt for no drain (option e), depending on the surgeon's assessment of the risk of postoperative complications.