At the top of the list is wrong site surgery, a surgical intervention performed on the wrong patient or wrong site, which has been recorded a shocking 1,584 times over the 8-year period. Mistakes that have happened within this category include the fallopian tube being removed instead of the appendix, the wrong toe being removed, and an injection into the wrong eye. Consequences of this can be mobility dysfunction, worsened injury, and the need to undergo further surgery. 

The second most common category is a retained foreign object post procedure, which refers to the retention of a foreign object in a patient after a surgical or invasive procedure. This has occurred 852 times from 2015 to 2023, with objects that have been mistakenly left inside patients’ bodies after procedures consisting of cotton wool balls, surgical needles, gloves, and clamps. Aseptic inflammation can occur as a result of this Never Event, which can lead to persistent pain and discomfort for months or even years. 

Next, with 431 recorded incidents over 8 years, is the wrong implant or prosthesis, where the incorrect implants and artificial body parts were given to patients that they were not intended for. Mistakes within this category include the implantation of a cranial plate that was custom made for another patient, the wrong pacemaker being fitted, and insertion of the wrong stent or feeding tube. This Never Event can cause infection and damage to the surrounding area – not to mention, further surgery becomes necessary, costing the NHS more money. 

Fourth is the administration of medication by the wrong route, which was recorded 180 times over the 8-year period. One example of this is oral medication being given to the patient subcutaneously, meaning medication was injected rather than swallowed, which can result in ineffective treatment and a prolonged stay in hospital. 

Next on the list, with 159 recorded incidents between 2015 - 2023, is a misplaced nasogastric or orogastric tube. These tubes placed either through the nose or the mouth that end with the tip in the stomach; an example of a mistake within this category includes the nasogastric tube being placed in the respiratory tract and feed being administered. Pneumonia and pneumothorax are just some of the conditions that can be fatal as a result of a misplaced nasogastric or orogastric tube. 

The unintentional connection of a patient requiring oxygen to an air flowmeter is the sixth most common Never Event in the NHS, happening 147 times over 8 years. This means that patients were connected to air instead of oxygen when oxygen was required. Consequences of this included respiratory arrest and cardiac arrest, which can be fatal. 

Seventh is the overdose of insulin due to abbreviations or the incorrect device, with 73 occurrences from 2015 to 2023. An insulin overdose may lead to severe hypos, which occurs when the level of sugar in someone’s blood drops too low, where the patient can become unconscious and have a fit. 

With 51 recorded incidents, the transfusion or transplantation of ABO incompatible blood components or organs is eighth. This refers to blood or organs that were transfused or transplanted to patients who did not have the correct blood type to accept them, which can cause a fever, pain in the back and sides of the body, and can even be fatal. 

The ninth most common medical mistake in the NHS is an overdose of methotrexate for non-cancer treatment, which occurred 32 times over the time period analysed. Methotrexate is an immunosuppressant used to treat auto immune diseases, ectopic pregnancies, and cancer, with the dose used to treat the latter often being much higher than the dose used for patients with other diagnoses. In this category of Never Event, patients who did not have cancer were given more methotrexate than they should have had for their diagnosis. An overdose of methotrexate can lead to serious adverse effects, such as the disturbance of liver function, bone marrow suppression, and gastrointestinal bleeding. 

Tenth is the failure to install functional collapsible shower or curtain rails, which was recorded 20 times in mental health inpatient facilities from 2015 to 2023. Collapsible shower and curtain rails are examples of anti-ligature devices, which are products designed to prevent patients from self-harm or suicide, and the NHS policy states that these rails should break away when a maximum weight of 40kg is applied to them. These Never Events were recorded when patients attempted or committed suicide while in an inpatient facility due to the shower or curtain rails not being collapsible.