Here are several ways to continue the sentence, each with a different implication:

**Focusing on the doctor's reason for lateness:**

* "...because he was late **due to unexpected traffic.**"
* "...because he was late **recovering from an emergency surgery.**"
* "...because he was late **finishing rounds at the other hospital.**"
* "...because he was late **struggling to find a parking spot.**"

**Focusing on the purpose of the call:**

* "...because he was late **and needed her to inform the waiting patients.**"
* "...because he was late **and wanted to make sure she was prepared for his arrival.**"
* "...because he was late **and needed her to reschedule his first appointment.**"
* "...because he was late **and wanted to update her on his estimated arrival time.**"

**Adding a consequence or emotional aspect:**

* "...because he was late, **and he knew she would be worried.**"
* "...because he was late, **and he didn't want to leave her in the dark.**"
* "...because he was late, **and he needed her to cover for him until he arrived.**"
* "...because he was late, **which was highly unusual for him.**"

**More descriptive or narrative:**

* "...because he was late, **his pre-surgical checklist still incomplete, and patients were already arriving.**"
* "...because he was late, **his voice a little harried as he explained his delay.**"

Choose the continuation that best fits the story or scenario you have in mind!
