Biomedical subjects

M Kalpokas

Publications and source records attributed to M Kalpokas.

4 recordsLinked to original sources

PubMed2004

Detection of cognitive decline after coronary surgery: a comparison of computerized and conventional tests.

BACKGROUND: Postoperative cognitive decline is a common complication after coronary artery bypass graft (CABG) surgery. Postoperative cognitive decline is defined on the basis of change in cognitive function detected with repeated assessments using neuropsychological tests. Therefore improvement in neuropsychological testing instruments may increase our understanding of postoperative cognitive decline. METHODS: Fifty patients undergoing CABG surgery completed both a conventional and a computerized battery of tests before and 6 days after CABG surgery. Fifty age- and education-matched controls completed the same test batteries 6 days apart. The reliability and the sensitivity to postoperative cognitive decline were computed for each battery. RESULTS: Both test batteries detected postoperative cognitive decline 6 days after CABG surgery. For the computerized battery, the reliability of the reaction times (intraclass correlation 0.89-0.92) was greater than for any test from the conventional battery (intraclass correlation 0.56-0.71), although accuracy measures were less reliable (intraclass correlation 0.61-0.89). The computerized battery detected all the cases of POCD identified by the conventional test battery and also five cases that were classified as normal by the conventional tests. CONCLUSION: Computerized tests are suitable for measuring cognitive change after CABG surgery and may detect change in a greater proportion of patients 6 days after CABG surgery than conventional neuropsychological tests.

Aged↗

PubMed1989

Physiological changes during liver transplantation.

Thirteen patients who received liver transplants at the National Liver Transplant Unit between January 1986 and March 1987 were studied with extensive monitoring and frequent intraoperative biochemical and haematological profiles. Anaesthetic technique was standardised for all patients. Retrospective analysis of this data confirms that patient homeostasis is most disturbed at the time of revascularisation of the donor liver. In this series, revascularisation was associated with marked changes in all measured haemodynamic parameters (arterial blood pressure, cardiac index, heart rate, and filling pressures). There was also a significant fall in pH with revascularisation, followed by a gradual rise during the final phases of the operation. Potassium levels often rose sharply with revascularisation but then decreased during the rest of the operative period. Ionised calcium levels did not change significantly at any stage; however, all patients were given calcium intraoperatively. Coagulation profiles were often abnormal preoperatively. The transplant procedure was associated with further abnormalities in both coagulation and fibrinolysis. Patient temperatures were maintained at normal levels throughout the procedure.

Adolescent↗

PubMed1989

A simple technique for diagnosing oesophageal intubation.

Undiagnosed oesophageal intubation during anaesthesia is a major cause of anaesthetic-related morbidity and mortality. A test was devised and evaluated to distinguish between placing an endotracheal tube in the trachea and in the oesophagus. The test involves threading a lubricated nasogastric tube through the endotracheal tube, applying continuous suction to the nasogastric tube and then attempting to withdraw the nasogastric tube. Four aspects distinguish an endotracheal tube in the trachea from one in the oesophagus: 1. the length of nasogastric tube inserted and the feel of the final obstruction to further insertion. 2. the ability to maintain unobstructed suction through the nasogastric tube, 3. the ease of withdrawal of the nasogastric tube during continuous suction, 4. the nature of any aspirate (i.e. mucus or gastric contents). An evaluation was performed on twenty patients in whom both the trachea and oesophagus were intubated simultaneously. In all twenty cases, each of the two endotracheal tubes was correctly identified as being either tracheal or oesophageal. The ability to maintain suction and the ease of withdrawal most clearly distinguished between the two positions.

Adult↗

PubMed1988

Liver graft revascularization by donor portal vein arterialization following "no touch" donor hepatectomy.

Unsatisfactory immediate function of the transplanted liver together with technical complications contribute to a persisting early mortality for hepatic transplantation in the 20% range. We report our initial clinical experience with methods, one not previously used clinically, that resulted in uniformly well-functioning liver grafts in 11 patients and contributed to a satisfactory success rate for the procedure. Donors were heart-beating. During the donor operation all manipulations of the liver were avoided until after cold preservation, achieved by external cooling at the same time as circulatory interruption, donor exsanguination and perfusion of the liver with cold oxygenated fluid of "extracellular" type. The organs were then gently dissected. At transplantation the livers were revascularized with arterial blood shunted from the recipient iliac artery to the graft portal vein after completion of the suprahepatic IVC anastomosis. The infrahepatic IVCs and hepatic arteries were then joined, the iliac artery shunts discontinued and the portal veins joined. Total ischaemic intervals for the allografts were 3 1/2-8 (average 5). Anhepatic intervals were 1-2 1/4 (average 2). The arterio-portal shunts were operating for 18-85 (mean 46) min. Blood loss and haemodynamic, acid-base and electrolyte abnormalities at revascularization were minimal. All grafts secreted bile immediately and all parameters reflected continuing improvement of liver function thereafter. Nine patients (82%) are alive between 4 and 18 (mean 11) months after transplantation. We conclude that these methods offer effective avoidance of serious organ damage during donor hepatectomy and preservation, reduced allograft ischaemic interval and reduced recipient anhepatic time. They result in avoidance of blood loss at the time of revascularization, together with minimal haemodynamic, acid-base or biochemical changes. In addition, they allow the surgeon to perform and test all anastomoses without time constraints, provide the capability to deal with unexpected complications, and assure good early graft function.

Adolescent↗