Cognitive dysfunction after on-pump operations: neuropsychological characteristics and optimal core battery of tests.

Anna G Polunina,Alla B Guekht,Elena Z Golukhova,Leo A Bokeria,Natalia P Lefterova

doi:10.1155/2014/302824

Abstract

Postoperative cognitive dysfunction (POCD) is a mild form of perioperative ischemic brain injury, which emerges as memory decline, decreased attention, and decreased concentration during several months, or even years, after surgery. Here we present results of our three neuropsychological studies, which overall included 145 patients after on-pump operations. We found that the auditory memory span test (digit span) was more effective as a tool for registration of POCD, in comparison with the word-list learning and story-learning tests. Nonverbal memory or visuoconstruction tests were sensitive to POCD in patients after intraoperative opening of cardiac chambers with increased cerebral air embolism. Psychomotor speed tests (digit symbol, or TMT A) registered POCD, which was characteristic for elderly atherosclerotic patients. Finally, we observed that there were significant effects of the order of position of a test on the performance on this test. For example, the postoperative performance on the core tests (digit span and digit symbol) showed minimal impairment when either of these tests was administered at the beginning of testing. Overall, our data shows that the selection of tests, and the order of which these tests are administered, may considerably influence the results of studies of POCD.

Highlights

Postoperative cognitive dysfunction (POCD) is a mild form of perioperative ischemic brain injury, which emerges predominantly as memory decline during several months, or even years after surgery [1,2,3,4,5]
In our analysis of 24 publications concerning neuropsychological outcomes of cardiac surgery [55], we found that studies which used a test battery recommended by Statement of Consensus on Assessment of Neurobehavioral Outcomes after Cardiac Surgery (i.e., Rey auditory verbal learning test (RAVLT), trail making test part A (TMT A) and B, and Pegboard test) showed significantly lower incidence of POCD after 1–3 months of follow-up, as compared to the studies which used digit span and nonverbal memory tests
Patients who performed digit symbol as the first test in the battery showed significantly better dynamics on this test, compared to the patients who performed this test in the middle or end of the testing (F2,27 = 5.61, P = 0.01)

Summary

Introduction

Postoperative cognitive dysfunction (POCD) is a mild form of perioperative ischemic brain injury, which emerges predominantly as memory decline during several months, or even years after surgery [1,2,3,4,5]. Patients commonly report decreased concentration, attention span, and psychomotor speed. Both patients and spouses of patients notice postoperative memory decline after the first year after operation [3]. Negative effects on driving abilities during several months after uncomplicated cardiac surgeries were registered [6]. Multiple neuropsychological studies confirm a decline in the performance of cognitive tests in the majority of patients during the first week after cardiac surgery and in about 30–40% of patients in 1–3 months after surgery in comparison with preoperative testing [review: [7]]

Methods

Results

Discussion

Conclusion