In addition, there's connecting service from Canada, Europe, South America and the Far East. Commuter service between San Juan, St. Croix and St. Thomas is also available. Commuter airlines can transport you between islands in as little as 17 minutes.n addition, there's connecting service from Canada, Europe, South America and the Far East. Commuter service between San Juan, St. Croix and St. Thomas is also available. Commuter airlines can transport you between islands in as little as 17 minutes.
A rough estimate is that it takes about 14 hours for blood to be broken down within the intestinal lumen; therefore if transit time is less than 14 hours the patient will have hematochezia, and if greater than 14 hours the patient will exhibit melena.
Symptoms of melena or blood in stool are: 1  Patient complains change of stool color to his medical attendant; it is dark black like coal tar. 2  Anemia is most important sign noted in patients with melena.3  Weakness.ymptoms of melena or blood in stool are: 1  Patient complains change of stool color to his medical attendant; it is dark black like coal tar. 2  Anemia is most important sign noted in patients with melena.