Given a passage, construct a question on the basis of the information present in the passage. Construct the question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) it answer uses text phrases from the passage. Avoid creating questions that (i) can't be answered correctly without actually understanding the passage and (ii) uses the same words or phrases given in the passage.

Q: The local anesthetic properties of tetrodotoxin, a potent naturally occurring sodium channel blocker, have been recently reexamined. It was found that sciatic nerve block duration could be greatly increased and systemic toxicity greatly decreased if epinephrine was injected with tetrodotoxin. The mechanism that underlies epinephrine-mediated prolongation of tetrodotoxin nerve blocks is not known, but indirect evidence suggests that epinephrine may slow the clearance of tetrodotoxin from the site of injection. The authors hypothesized that tetrodotoxin causes vasodilatation at its injection site, which accelerates its systemic uptake, and that this vasodilatation is attenuated by coinjected epinephrine.', 'The radiolabeled microsphere technique was used to measure tissue blood flow in anesthetized rats before and after perisciatic injection of tetrodotoxin alone and in combination with epinephrine.', 'Tetrodotoxin, in a dose of 0.1 ml of a 60 microM solution, significantly increased blood flow in perisciatic muscle at the injected side compared with simultaneous contralateral control and ipsilateral preinjection baseline. Tetrodotoxin did not increase blood flow in the sciatic nerve. Coinjection of epinephrine with tetrodotoxin prevented tetrodotoxin-induced increases in perisciatic muscle blood flow over time and did not alter sciatic nerve blood flow. Arterial blood pressure was maintained with this dose of tetrodotoxin, although brain blood flow decreased. Coinjection of epinephrine with tetrodotoxin prevented decreases in brain blood flow. Higher doses of tetrodotoxin produced hypotension.

A: Does epinephrine prevent muscle blood flow increases after perineural injection of tetrodotoxin?
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Q: Hypocalcemia is the most common complication after total thyroidectomy. Some patients need to stay in the hospital for monitoring of hypocalcemic symptoms and serum calcium levels for several days. We investigated the efficacy and safety of using early postoperative parathyroid hormone (PTH) results for early discharge after thyroidectomy.', 'A retrospective cohort study of 2 sequential groups of patients undergoing total thyroidectomy between January 2010 and March 2013 was undertaken. Patients were divided into 2 groups. In Group 1 (before June 2011), patients had daily monitoring of serum calcium level and hypocalcemic symptoms. They were discharged when calcium level was static and asymptomatic. Postoperative PTH was not utilized for discharge plan. In Group 2 (after June 2011), postoperative PTH and calcium level on day 1 were utilized to dictate subsequent management and discharge plan.', 'Of the 107 patients reviewed, 54 (50.5%) were in Group 1 and 53 (49.5%) were in Group 2. A total of 51 (47.7%) patients developed hypocalcemia. The two groups were comparable in demographic data, early postoperative PTH value, rate of hypocalcemia, the need for oral calcium and vitamin D supplements and rate of permanent hypoparathyroidism. Fewer patients in Group 2 experienced hypocalcemic symptoms, p=0.005. None of the patients in Group 2 needed intravenous calcium supplement (p=0.003). The median postoperative hospital stay for Group 1 was 4 days and for Group 2 was 1 day (p<0.0001).

A: Does postoperative PTH monitoring of hypocalcemia expedite discharge after thyroidectomy?
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Q: Meckel's diverticulum (MD) is the most common congenital anomaly of the gastrointestinal tract. Although a majority of patients remain asymptomatic, complications may occur in a subset of patients. MD is a rare cause of gastrointestinal bleeding (GIB) in adults. We aimed to clarify the possible role of capsule endoscopy (CE) in the identification of Meckel's diverticulum.", 'From October 2004 to December 2010, 157 CEs were performed (83 male individuals, mean age 51±20 years; range 3-83 years) for obscure GIB. Before CE, all patients underwent nonconclusive upper and lower endoscopy at least two times and barium follow-through.', 'CE identified the source of bleeding in 70/157 patients (44.6%). MD was diagnosed in 13/70 (18.6%) patients (11 male individuals, mean age 35±20 years, range, 3-69 years) after CE. Nine patients presented with obscure overt and four with obscure occult bleeding. The mean duration of obscure GIB history was 13 months (range 1-72 months). The mean hemoglobin concentration at the time of the procedure was 115±12\u2009g/l. The findings of MD on CE were double lumen sign (13/13), visible blood (7/13), and diaphragm sign (6/13). All patients were operated upon, and MD histologically verified in 11. In two patients CE was false-positive and in two patients, false-negative. Capsule endoscopy had a positive predictive value of 84.6% for the diagnosis of MD.

A:
Is capsule endoscopy useful diagnostic tool for diagnosing Meckel 's diverticulum?
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