ABSTRACT
Electrocardiogram (ECG)-triggered laser Doppler perfusion monitoring (LDPM) was used to assess myocardial perfusion, with minimum myocardial tissue motion influence, during coronary artery bypass grafting (CABG). Thirteen subjects were investigated at six phases: pre- and post-CABG; post aorta cross-clamping; pre and post left internal mammary artery (LIMA) graft declamping; and post aorta declamping. The perfusion signal was calculated in late systole and late diastole, with expected minimum tissue motion, and compared with arrested heart measurements. Patient conditions or artifacts caused by surgical activity made it impossible to perform and analyse data in all six phases for some patients. No significant (n = 5) difference between perfusion signals pre- and post-CABG was found. Diastolic perfusion signal levels were significantly (p < 0.02) lower compared with systolic levels. After aorta cross-clamping, the signal level was almost zero. A distinct perfusion signal increase after LIMA and aorta declamping, compared with pre-LIMA declamping, was found in ten cases out of 13. A significantly (p < 0.04) lower perfusion signal in the arrested heart compared with in the beating heart was registered. Influence from mechanical ventilation was observed in 14 measurements out of 17. In conclusion, ECG-triggered LDPM can be used to assess myocardial perfusion during CABG. Perfusion signals were lower in the arrested heart compared with in the beating heart and in late diastole compared with late systole. No significant difference between pre- and post-CABG was found.
Subject(s)
Coronary Circulation , Internal Mammary-Coronary Artery Anastomosis , Monitoring, Intraoperative/methods , Adult , Aged , Electrocardiography/methods , Female , Heart Arrest, Induced , Humans , Laser-Doppler Flowmetry/methods , Male , Middle AgedABSTRACT
Laser Doppler perfusion monitoring (LDPM) is an established method for microvascular measurements. When applied to the beating heart, however, movement artifact contributions will result in an overestimation of the perfusion. In order to overcome this problem, the perfusion signal may be processed in relation to intervals in the cardiac cycle with minimal tissue motion, e.g., in late systole and late diastole. The aim of this study was to develop an electrocardiogram (ECG) tracing algorithm for R, T and P wave detection and to use these peaks to process the perfusion in intervals with minimal motion. The algorithm, evaluated in three subjects, detected the peaks correctly to 99.9% under ideal conditions. Used on a heart patient in postoperative care this was reduced to 93.2%. However, since the overall goal is to monitor changes in the myocardial perfusion over hours or even days, it is not necessary to capture perfusion values in every single heartbeat. Time traces of perfusion captured in relation to the T and P waves showed a periodical behavior. In order to tune the processing and presentation of the perfusion signal, future studies will focus on long term monitoring of myocardial perfusion during heart surgery and in the postoperative care.
Subject(s)
Drug Prescriptions/statistics & numerical data , Homes for the Aged , Nursing Homes , Aged , Humans , SpainABSTRACT
We report the evaluation of a pilot study for the nutritional state carried out at a Health Center in Murcia, using a qualitative foodstuff questionnaire related to the previous 24 hours and the evaluation of anthropometric and analytical data. The evaluated individuals were randomly selected between the persons who had previously consulted. The survey was carried out by an interviewer. An outstanding result was that 90% of the surveyed individuals had ingested, at least one foodstuff from each group. The fat compartment was measured through the tricipital and subscapular fold and Quetelet index, and the protein compartment was measured through the muscular area of the arm. As reference values, the NHANES (USA) and the Alastrue Vidal (Spain) tables were used. It was found that the tricipital fold of the investigated population was underrated in the american tables (p less than 0.01).
Subject(s)
Diet , Nutritional Status , Adolescent , Adult , Aged , Anthropometry , Catchment Area, Health , Female , Humans , Male , Middle Aged , Pilot Projects , Socioeconomic Factors , SpainABSTRACT
The transfer of deuterium from [1 R-2H]ethanol and [1 S-2H]-ethanol to reduced metabolites of administered compounds was measured in female rats provided with bile fistulas. Administered cyclohexanone was reduced to cyclohexanol, and in this reduction hydrogen was transferred only from the 1-pro-R position of the ethanol. The deuterium content in the cyclohexanol was about 67% of that in the ethanol. In the reduction of the 17-oxo group in 3beta-hydroxy-5alpha-androstan-17-one, hydrogen was transferred both from the 1-pro-R position and the 1-pro-S position, resulting in degrees of labelling that were about 25% and 2%, respectively, of those in the specific positions of the ethanols. The 1-pro-R and 1-pro-S positions of ethanol contributed about 9% and 5%, respectively, of the 3beta hydrogen in lithocholic acid formed from 3-oxo-5beta-cholanoic acid. The results indicate that alcohol dehydrogenase and aldehyde dehydrogenase do not share a common pool of NAD, and that NADH formed during acetaldehyde oxidation is utilized for reductions in the cytosol to a smaller extent than the NADH formed in the alcohol dehydrogenase reaction. This result supports the concept that aldehyde oxidation is mainly an intramitochondrial process. The relatively extensive utilization of the 1-pro-S hydrogen of ethanol in the reduction of 3-oxo-5beta-cholanoic acid, that is probably NADPH-dependent, indicates that cytosolic NADPH may be produced from malate or isocitrate formed intramitochondrially.
