Nosocomial Infections

Nosocomial infections are infections which develop in a hospital setting. In the United States the CDC estimates about 1.7 million nosocomial infections from various types of organisms occur annually. Nearly 100,000 deaths occur each year related to these infections. Over the course of most of my medical career nosocomial infections have been primarily related to when we have put for materials and unnatural places. Examples of this are endotracheal tubes (to placed in the trachea to protect the airway and allow mechanical ventilation), urinary catheters, intravenous or intra-arterial catheters, and nasogastric feeding tubes. All of these types of infections are felt to have enter the body along the path of the tube to allow organisms access to areas they normally couldn’t get to. These infections are very important problem because in addition to giving access of organisms to unnatural places hospitals are places where large amounts antibiotics are used and tend to have very high rates of highly antibiotic resistant microorganisms. Community acquired pneumonia is very likely to be from organisms that will respond to a wide variety of antibiotics. The same is true of community acquired urinary tract infection. The same infections were acquired in a hospital setting, especially in intensive care hospital setting, are very often caused by highly resistant bacteria that would rarely cause the same infections in patients not in a hospital.

In recent years additional nosocomial infections have become major problems. In addition the organisms that had tended to be large when hospitals in past years like methicillin-resistant staph aureus are now very widespread in most communities. Among most difficult of the common nosocomial infections today is Clostridium difficile. C diff infection is a well-known issue in his usually related to antibiotic use. C diff infection is among the well-known amoxicillin side effects, Bactrim side effects and really a side effect of almost any antibiotic. Because antibiotics are widely used in hospitals C diff infections are quite common. This organism has a number of characteristics that make it extremely difficult to eradicate. It can exist in a latent form called a spore which can survive for long periods of is time on inert surfaces and yet when ingested can reawaken and cause a severe and sometimes life-threatening diarrheal illness. In addition to being difficult to eradicate Clostridium difficile (C. diff) has become highly antibiotic resistant. In the past Clostridium difficile was nearly universally sensitive to orally ingested vancomycin and to metronidazole. Now we are seeing highly resistant cases of Clostridium difficile that are refractory to essentially all available antibiotic therapy. Previously unheard-of treatments including fecal transplant have been studied for management of this difficult condition.

Medicare has made an attempt to incentivize hospitals to reduce the incidence of nosocomial infections by making some types of Hospital acquired complications non-reimbursable. As a result hospitals are doing things like screening patients for MRSA on admission to the hospital for the primary reason of having an argument to Medicare that if they developed a postoperative or in hospital nurse infection they can try to be compensated for care of that infection by showing that the patient harbored the organism causing the infection prior to admission. Otherwise patients who develop a MRSA infection while in the hospital and require longer hospitalization or additional procedures as a result of the nosocomial infection have to be cared for hospital some expense. These so-called “preventable infections” following some elective procedures are not covered by Medicare.

One of these selected conditions for Medicare non-reimbursable is catheter associated urinary infection. These are a notoriously difficult problem. Patients in the hospital are often unable to get out of bed in time to get to the toilet and an easy solution to this is to place an indwelling urinary catheter. An advantage of an indwelling urinary catheter is that it keeps patients from lying on wet sheets which can lead to decubitus ulcer. Decubitus ulcer is another condition selected by Medicare is a non-reimbursable preventable nosocomial condition. The way to prevent catheter associated infections is to minimize the time indwelling urinary catheters are used. The way to prevent pressure ulcers is to turn patients frequently and keeps them from lying on wet bedsheets. Although it’s certainly theoretically possible to minimize urinary catheter use and also prevent decubitus ulcers early removal of indwelling urinary catheter makes pressure ulcer prevention more difficult.

A great deal of progress has been made in the prevention of endotracheal it to associated respiratory infections. Endotracheal tube design has been improved, respiratory therapy techniques have been refined and various other improvements have been implemented but nonetheless patients in the hospital who require endotracheal intubation for more than very brief periods of time are at high risk for hospital acquired pneumonia. Many hospital acquired pneumonia cases are infections with antibiotic resistant gram-negative bacteria. These, nosocomial pneumonias can require therapy with parenteral antibiotics which greatly prolong hospital stays and often require long-term intravenous access.

Long-term intravenous access itself is a risk factor for nosocomial infections. The longer and IV stays in place the higher the incidence of blood-borne bacterial infection complicating the situation. These bacterial infections are also often due to highly antibiotic resistant organisms. Use of good sterile technique while placing IVs, changing IV sites regularly, and frequent assessment of the IV site for early signs of infection can reduce the chances of intravenous catheter related bacteremia but certainly don’t eliminate it.

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