**Introduction**

**1** 

*Poland* 

**Postoperative Cognitive Dysfunction** 

**(POCD) and Markers of Brain Damage** 

Brain dysfunction can manifest itself either as focal laesions or mental impairment (Roach et al., 1996). In orthopedic patients, in comparison to any other group of hospitalized people, cognitive dysfunction was present more often. It included a deterioration of perception, memory, information analysis, attentional focus as well as of concentration and decreased patients' response (L. S. Rasmussen, 1998). When occurring after a surgery, the symptoms were defined as Postoperative Cognitive Dysfunction (POCD) (Newman, Stygall, Hirani, Shaefi, & Maze, 2007) and were nonspecific signs of brain disorders resulting from cellular abnormalities. Very often the dysfunction's nature was subclinical and no changes in diagnostic imaging were present (Wu, Hsu, Richman, & Raja, 2004). As a consequence, the hospitalization time was longer, the outcome and quality of life were worsened as well as prolonged medical and social assistance were necessary (Gao et al., 2005; Veering, 1999). The problem concerned up to 26% of elderly patients during the first week after a non-cardiac surgery (Rohan et al., 2005). Amongst 60-year-old patients who underwent major surgical procedures under general anesthesia lasting over 2 hours, 10% suffered from memory impairment and concentration problems for more than 3 months after the surgery. The disorder occurs twice more often in 70 – 80-year-old people in comparison to 60 – 70-yearolds (Harwood, 2000). According to statistic data, about 70% of the patients with POCD die within 5 years compared to about 35% of the patients without postoperative delirium

All above data were alarming, but the problem seemed to be more complex. The diagnosis of POCD depends on performing a proper assessment of the cognitive function before and after the surgery through a battery of neuropsychological tests, so the incidence of POCD varies. According to the work of Blaise et al., the variability can result from nonstandardization of neuropsychological tests performed at different times of the day, lack of a control group, differences in significance levels between studies as well as from the socalled "learning effect", as when the same test is applied to the same person many times (Blaise, Taha, & Qi, 2007). Another question concerns the time at which the diagnosis of POCD was made. Different drugs administered in the perioperative period can affect patients' cognition. Thus some authors believe that the diagnosis of POCD should be made

**1. Introduction** 

(Fodale, Santamaria, Schifilliti, & Mandal, 2010).

not earlier than 2 weeks after the surgery (Blaise, et al., 2007)

**After Big Joints Arthroplasty** 

Dariusz Tomaszewski *Military Institute of Medicine* 
