Kamala Harris on Friday morning became the first woman to wield presidential power in the US – temporarily, when Joe Biden had a colonoscopy under anesthetic. In a statement, the White House press secretary, Jen Psaki, said: “This morning, the president will travel to Walter Reed Medical Center for a routine physical. While he is there, the president will undergo a routine colonoscopy. “… The vice-president will work from her office in the West Wing during this time.” Biden left the White House before 9am. The White House said it would share results of his physical. Just after noon, Psaki said Biden had resumed power. The president “spoke with [Harris] and [Chief of staff Ron Klain] at approximately 11.35am”, Psaki tweeted, adding that Biden was “in good spirits and at that time resumed his duties. “He will remain at Walter Reed as he completes the rest of his routine physical.” Such temporary transfers of power have been made before. As Psaki pointed out, in 2002 and 2007, Vice-President Dick Cheney assumed the role of temporary president when George Bush had colonoscopies. Unsurprisingly, Donald Trump reportedly bucked accepted practice. According to his former press secretary Stephanie Grisham, the 45th president refused anesthetic when he had what was in all likelihood a colonoscopy – Grisham described a “very common procedure” similar to that which Bush had – in November 2019. Trump, Grisham wrote, refused anesthetic because he did not want his vice-president, Mike Pence, to be even temporarily in charge. She also said Trump “did not want to be the butt of a joke”. The health of all presidents is closely watched. Trump’s visit to Walter Reed – and its cack-handed cover-up – prompted reports he had suffered a heart attack. Past 70 when he was sworn in, Trump was the oldest president elected for a first time until Biden surpassed him. Biden will turn 79 later this month. After his last publicised physical, in December 2019, doctors pronounced him “healthy, vigorous” and “fit to successfully execute the duties of the presidency”. He has, however, survived two brain aneurysms, the second in 1988 when he was 45. Should he become incapacitated for longer than required for a regular procedure, the 25th amendment to the US constitution provides for his replacement by Harris. The amendment, which also dictates the means by which temporary power is passed, has never been invoked in full. In a book published this week, the journalist Jonathan Karl reported that senior cabinet officials discussed it in the wake of the Capitol attack, over concerns about Trump’s mental health. Harris is the first Black, Asian woman to be vice-president, but her short spell in power on Friday came amid reports she is struggling and often at odds with Biden. The White House has defended her. On Thursday, Psaki told Politico there was “no question” that racism and sexism were part of “attacks” against the VP. On Thursday night, it was reported that Harris’s communications director, Ashley Etienne, will leave her role in December. Amid intense speculation about what Etienne’s departure might mean, James Clyburn of South Carolina, the House whip and a close Biden adviser, told CNN: “People leave jobs all the time. “I’ve been a part of transitions myself at the state level. And I know that within the first several months – sometimes it takes a year – that people may find out, ‘This is not exactly for me.’ So these things tend to happen.” Biden was due to carry out a key duty on Friday afternoon: pardoning the White House Thanksgiving turkey.