Jacob Gaskell had also taken cocaine and cannabis before driving the Land Rover Freelander which crashed outside Fifteens, on Ormskirk Road, Pemberton, on Friday, April 8.
He had never held a driving licence and claims he passed out at the wheel due to the nitrous oxide, Bolton Crown Court heard.
The car hit teacher Laura Hazeldine, 44, who died from horrific injuries, while twin brothers Jack and Ben Atherton were also hurt.
Gaskell – who turned 19 the following day – is now behind bars after being jailed for nine years.
Rachel Woods, prosecuting, said three teenage girls arranged to meet a friend in Garswood that night and he arrived in a car driven by Gaskell.
They had not met Gaskell before, but got in the car and travelled towards Pemberton.
Loud music was playing, no-one wore a seat belt and a large gas cannister was being used to fill up balloons to be inhaled, the court heard.
The car sped up and Gaskell ignored a plea from the girls to slow down, with at least one asking to be let out.
Gaskell asked for a balloon, which he inhaled while driving.
He started driving faster along Ormskirk Road, with one witness noticing the car close behind her and flashing its headlights at full beam.
Gaskell’s car veered to the centre of the road as if to overtake, Ms Woods said, but there was traffic coming in the opposite direction and nowhere for it to go.
It mounted the pavement outside Fifteens and hit Ms Hazeldine and the Athertons.
One of the brothers was “catapulted” into the air and did “three somersaults” before landing on the ground.
The court heard one of the girls in the car blacked out and another was injured, while Gaskell ran away.
Ms Woods said: “Various witnesses who saw the aftermath of the collision were simply overwhelmed by the carnage at the scene that the defendant left behind. Many people went to assist the injured and immediately called for help. The parents of Ben and Jack Atherton were hysterical when they came out of the pub and saw what had taken place.”
Jack, who was home from the army, suffered concussion, lacerations and bruises.
Ben had a fractured spine, three small bleeds on his brain, lacerations to his kidney and other injuries. He had to stay immobile for eight weeks and now does not know when he can join the army, having previously passed assessments
Laura, who had been enjoying a night with her sister Rachel, suffered horrendous lower limb injuries, facial injuries, fractures to her neck and spine, multiple rib fractures and internal injuries.
She was rushed to Wigan Infirmary, but was pronounced dead at 11.06pm.
Laura’s mother Gillian Webster spoke about the close relationship she had with her three children, who were her “world”.
She was “inseparable” from Rachel, cared for her poorly father and touched everyone she met.
She said: “Laura’s life was working hard and being the best mum, daughter, sister, work colleague and teacher, studying for her degree in mathematics. Laura was always a reliable source for us all and loved by all who came into contact.
"I will never forget the severe injury she sustained and her fight for life and I watched her sadly passed away.”
Mrs Webster spoke about rushing to Fifteens, to find Laura badly injured and receiving CPR from a nurse.
She went to hospital and watched as medics tried to save her daughter.
To Gaskell, Mrs Webster said: “Your actions have devastated our family and we will never recover from the loss. We will never get her back. I hope you learn your lesson and spend time thinking and reflecting on your actions and you never put another family through the heartache and sorrow that you have put us through.”
Gaskell, of Marlborough Avenue, Ince, was arrested in the early hours.
Blood tests showed he had used cocaine and cannabis before the crash. A metabolite of cocaine was found at a level of 466, with the maximum limit for driving being 50.
Ms Woods said nitrous oxide – laughing gas – was not detected, but it can leave the body quickly.
Checks found Gaskell had bought the car and it was registered as being off-road.
Earlier this year he was given a six-month custodial sentence, suspended for 24 months, for dangerous driving and aggravated vehicle taking, after stealing a delivery van in Golborne, speeding away when pursued by police and crashing into a car.
Gaskell was also subject to a community order for assaulting an emergency worker.
He pleaded guilty to causing death by dangerous driving, causing death by driving while disqualified, causing death by driving without a licence, causing death by driving while uninsured, causing serious injury by dangerous driving, driving while disqualified and driving without insurance. He also admitted breaching the suspended sentence order.
Andrew Nuttall, defending, said Gaskell accepted he was responsible for what happened, expressed his remorse and knew he would receive a long sentence.
He said: “He’s 19, not much more than a boy. It’s going to be a very, very long life potentially for him to live with what he has done.”
Gaskell’s family was “struggling to come to terms” with what happened, he said.
A psychiatrist found Gaskell had emotionally unstable personality disorder, probably caused by using illegal drugs since he was 14.
Sentencing, Judge Tom Gilbart said Gaskell getting behind the wheel showed “breath-taking arrogance”.
He said: “No sentence that this court imposes today can possibly compensate for the tragic and totally unnecessary loss of this much-loved woman.”
Gaskell was jailed for eight years and eight months, with a further four months added for breaching the suspended sentence.
He was banned from driving for 14 years and four months.