One of New York City’s top-earning surgeons, already under investigation for double-booking surgeries, used a barely trained nurse as his surgical assistant in complex procedures, hospital documents show.

Four operating-room reports from Lenox Hill Hospital list a licensed practical nurse as the assistant to Dr. David Samadi, a prostate cancer specialist, according to copies of the reports provided to The Post.

Alejandro Alamon is shown as the assistant in the operations, which took place in 2014 and 2016. Each involved the removal of cancerous prostates using a surgical robot.

LPNs receive far less training than registered nurses and their duties are limited to basic tasks such as taking vital signs, giving medication and changing dressings.

The state Education Department, which licenses nurses, allows LPNs to work in the operating room, but not beyond their defined scope of practice.

“I don’t know of anybody, anybody, anybody using an LPN in an operating room,” one New York City surgeon told The Post. “LPNs are not surgical assistants.”

In fact, LPNs are not generally allowed as surgical assistants at Lenox Hill, a spokeswoman told The Post.

“If and when any personnel issues are brought to our attention, we act appropriately,” said spokeswoman Barbara Osborn, who noted the hospital took action in the matter but would not specify what it did.

Samadi, a prolific surgeon, returned this week to his Lenox Hill surgical suite after not having been seen there earlier this month.

He earned $6.8 million in 2017, down from $7.3 million the previous year, according to Lenox Hill’s tax filings.

He had been chairman of the urology department and chief of robotic surgery, but lost those posts this year.

Samadi declined to comment last week, saying his lawyer would respond to questions. No lawyer called.

James Glasser, Samadi’s lawyer, said the doctor was “one of this country’s foremost urologists and one of the world’s leading surgeons performing robotic surgery ” and that “Since 2013, he has worked with the very experienced surgical team recruited by (Lenox Hill parent company) Northwell Health and Lenox Hill Hospital and is proud of the high quality of care that they together have provided to their patients.”