Defending medicolegal cases relating to Intensive Care Unit acquired infections 

A hospital-acquired infection (HAI) is any infection that is not clinically manifest or incubating at the time of admission. Conventionally, infections that become evident within 48 hours of admission are deemed to be community-acquired, while those that appear later, unless there is clear evidence of their existence at admission, are classified as hospital-acquired.  

HAIs are common, affecting around 6.5% of patients, with a higher prevalence in the intensive care unit (ICU). They result in increased morbidity and mortality and can significantly lengthen a patient’s stay in hospital. Across the European Union, some 501 disability-adjusted life years per 100,000 inhabitants can be attributed to HAIs. The most commonly encountered infectious organisms include Enterobacteriaceae, Pseudomonas aeruginosa, Staphylococcus aureus and Clostridium difficile. Infections caused by organisms that are resistant to antimicrobial agents, such as methicillin-resistant S. aureus (MRSA) are particularly problematic, as the therapeutic options are limited.  

For a claim of medical negligence to succeed, the claimant must demonstrate that either they, or their relative, suffered damage which resulted from an act of negligence, usually defined as a departure from usual or reasonable practice in the given circumstances. This negligence could be due to the actions of one individual, or a failure in the organisation of the hospital. Finally, there must be a causal link, ideally with a high degree of certainty, between the act of negligence and the alleged damage.  

Therefore, the claimant would need to prove that the ICU-acquired infection was solely due to the negligence of the medical staff or poor hospital procedures. Often, however, the development of an ICU-acquired infection is actually a reflection of the severity of the patient’s condition, and impaired immunity is particularly implicated. Furthermore, rates of community-acquired infections, which may be brought in by the patients themselves, or visitors and staff, tend to be high in the ICU environment.  

In some cases, ICU-acquired infections are transmitted from one patient to another by the hospital staff. However, given the high rate of community infection, it would be very difficult to prove that patient-to-patient infection had occurred. This is complicated further by the fact that in around 20% of infections, the micro-organism responsible is never identified and therefore the source cannot be definitely proved.  

Infection control measures such as hand hygiene and patient isolation can be effective in preventing the spread of infections such as MRSA between patients. Therefore, a successful defence must show that infection control measures are in place and are adhered to by staff, ideally at rates higher than the 50% generally reported in the literature. The spread of ICU-acquired infection is rarely due to any one single factor, and prevention is achieved through a multitude of surveillance and hygiene measures; determining which specific factor was causal is normally extremely difficult. Furthermore, the benefit of precautions to prevent patient-to-patient spread of infections is not entirely clear. Where there is a high background rate of resistant pathogens or community-acquired MRSA, the use of gowns and gloves in an attempt to prevent the spread of infection is likely to be of limited effectiveness. However, this does not mean that they should not be used.  

Many additional factors contribute to a patient’s risk of developing an ICU-acquired infection, including the severity of their illness, duration of ICU stay, presence of a surgical wound, exposure to broad-spectrum antibiotics, previous medications and concurrent diseases, such as diabetes. More generally, overuse of prescription antibiotics has led to resistance in various pathogens, thus increasing the risk of infection.  

As many ICU-acquired infections are associated with the use of catheters, one of the most important risk factors is the meticulousness of the procedure used to insert the line. A successful defence must show that the doctor inserting the line used a sterile gown and mask, and an antibiotic-coated catheter. The site and ease of insertion, as well as the reason it was required, should also be recorded. The use of controlled and sterile conditions during line insertion may also minimise the impact of any breaches in contact precautions subsequently made by nursing and other staff.  

Liability for an HAI may also arise if it can be shown that there was a lack of informed consent. However, in the types of emergency situations frequently encountered in an ICU, patients may be unable to give consent and it may be sufficient for hospital staff to assume hypothetical consent, meaning that the patient would have agreed to treatment, despite the risk of subsequently developing an HAI. The claimant would need to prove that if the patient had been conscious and the situation non-life-threatening, consent for treatment would have been refused had the patient known about the risk of infection.  

Although ICU-acquired infections can be a significant complication of critical illness, their presence does not necessarily indicate poor medical care. Many claims are based on misconceptions and lack of communication between the parties involved. Thus, greater openness may prevent litigation. As well as infection control measures, many other factors influence the likelihood of a patient developing an ICU-acquired infection. Demonstrating that the patient received good care throughout their hospital stay, including adherence to effective infection prevention measures, should help to ensure the successful defence of any claims that may subsequently arise.