A boy who went into hospital suffering from a hernia and emerged to face a lifetime of acute disability, having allegedly been given a morphine overdose, has achieved a settlement of his claim worth at least £5 million.

The boy was aged five when he was given morphine to cope with the acute pain of a diaphragmatic hernia which was so serious that it pushed his heart over to the right side of his body. He was being cradled in his father's arms when the painkiller was administered. He suffered a sudden collapse and stopped breathing shortly afterwards.

Doctors succeeded in reviving him but he has been left with profound neurological disabilities affecting all four limbs. He is unable to walk without assistance and is only able to communicate using eye movements. He also has severe learning difficulties and will remain wholly dependent on others throughout his life.

The NHS trust which managed the hospital conceded full liability for what happened and agreed to a settlement of the case whereby the boy will receive a £3.2 million lump sum as well as annual, index-linked and tax-free payments to cover the costs of his care for life. The payments will start at £265,000 before rising to £305,000 when he reaches the age of 18.

The trust issued an apology in open court before the settlement was approved by a judge.