Deep pericardial sling versus lateral pericardial sutures in off-pump coronary artery bypass surgery.

AIM: The aim of this study was to evaluate the safety and efficacy of deep pericardial sling (DPS) versus lateral pericardial sutures (LPSs) for heart stabilization and adequate coronary artery exposure during off-pump coronary artery bypass surgery (OPCAB). METHODS: One surgeon employed in 101 consecutive patients a series of four to six 2-0 polyglactin sutures placed laterally between the left phrenic nerve and the left pulmonary veins (LPS). Two other surgeons used in 104 consecutive patients a single 0-0 braided silk suture with moistened gauze placed in the oblique sinus of the posterior pericardium, between the inferior vena cava and the right lower pulmonary vein (DPS). RESULTS: One conversion to beating heart surgery with cardiopulmonary bypass support occurred in each study group. No patient in the LPS group was converted to DPS technique. The use of LPSs allowed a number of distal anastomoses somewhat higher than the DPS technique (4.1+/-1.1 vs. 3.7+/-1.1, P=0.02). Postoperative results were similar in both study groups. A lower incidence of postoperative low-cardiac output syndrome and of prolonged need of inotropes has been observed in the LPS group, but the difference failed to reach statistical significance. One patient in the LPS group had postoperative left phrenic nerve palsy. One patient in the DPS group suffered of intraoperative bleeding secondary to rupture of the inferior vena cava likely related to placement of DPS, which was successfully repaired. CONCLUSION: LPS technique is as effective as DPS technique and allows complete revascularization with a postoperative outcome similar to the latter technique.

Changes in natriuretic peptides, apelin and adrenomedullin after off-pump and on-pump coronary artery bypass surgery.

AIM: The authors have evaluated the postoperative changes of natriuretic peptides, apelin and adrenomedullin after off-pump (OPCAB) and on-pump coronary artery bypass surgery (CCAB) to assess the impact of these techniques on the myocardium. METHODS: Twenty-two patients underwent OPCAB and 24 patients underwent CCAB. Plasma levels of NT-proANP, NT-proBNP, apelin and adrenomedullin were measured preoperatively, and on the 1st, 3rd, and 5th postoperative day. RESULTS: Natriuretic peptides, apelin and adrenomedullin increased significantly postoperatively. Natriuretic peptides were markedly elevated on the fifth postoperative day. Apelin was still increasing, but adrenomedullin, although elevated, clearly decreased toward baseline levels on the fifth postoperative day. CCAB was associated with significantly higher postoperative cTnI, but levels of natriuretic peptides, adrenomedullin and apelin did not differ significantly after CCAB and OPCAB. cTnI, echocardiographic parameters, cardiac index, and degree of postoperative pericardial effusion did not correlate with levels of natriuretic peptides, apelin and adrenomedullin. Postoperative levels of natriuretic peptides were significantly associated with parameters of renal function, age, and extracardiac arteriopathy. The correlation between preoperative estimated glomerular filtration rate and natriuretic peptides increased along the study intervals (NT-proANP rho: -0.181, -0.350, -0.364, and -0.442; NT-proBNP rho: -0.112, -0.420, -0.405 and -0.550). Also adrenomedullin correlated with parameters of renal function. The postoperative levels of apelin were not associated with any variable. CONCLUSION: A marked, sustained and similar increase in these five markers of cardiac adaptation was detected after OPCAB and CCAB. The upregulation of these peptides should be further investigated to evaluate their potential beneficial/harmful impact on the outcome after coronary surgery.

Risk of retinal microembolism after off-pump and on-pump coronary artery bypass surgery.

AIM: In order to investigate the neuroprotective efficacy of off-pump coronary artery bypass surgery (OPCAB) over conventional on-pump coronary artery bypass surgery (CCAB), we have performed a prospective randomized study evaluating retinal circulation changes after OPCAB and CCAB. METHODS: Twenty patients were randomized to OPCAB or CCAB. Retinal fluorescein angiography and 60 degrees black-and-white as well as color fundus photographs of both eyes of each patient were taken 1 to 24 h before and 5 to 6 days after the operation. RESULTS: Patients undergoing OPCAB had more severely stenosed carotid arteries (P=0.075), higher incidence of slightly diseased ascending aorta (P=0.087) and higher Northern New England Cardiovascular Study Group stroke risk score (P=0.075). Neither stroke nor transient ischemic attack occurred postoperatively in these patients. Inferotemporal retinal arterial embolization and microinfarction was detected in one patient after CCAB, but in none of the OPCAB group. CONCLUSION: The risk of retinal embolism can be minimized by the use of OPCAB and, most likely, by adequate epiaortic ultrasound scanning of the ascending aorta and avoiding clamping in case of severely diseased aorta.

Cell-adhered conjugated linoleic acid regulates isomerization of linoleic acid by resting cells of Propionibacterium freudenreichii.

The microbiological isomerization of linoleic acid (LA) to conjugated linoleic acid (CLA) was studied in resting cell suspensions of a propionibacterium and micellar LA to identify factors critical in the isomerization efficiency. These suspensions, containing cells 5x10(10) colony-forming units ml(-1) and 510 micro g LA ml(-1), isomerized about 90% of LA to CLA. However, the yield was not improved with higher amounts of micellar LA, suggesting that the cells had a fixed capacity to carry out the isomerization. This was explained by the fact that the CLA formed had a tendency to accumulate in the cell mass rather than in the aqueous micellar phase during the isomerization. Concomitantly, cell viability and isomerization rates were gradually reduced. Upon cessation of the reaction, about 46% of all the CLA formed was in the cell material. This accumulation to the cells was prevented by adding the detergent in excess to that required for micellization of LA. Then the cells remained viable, but the rate of isomerization was drastically lowered, due to impaired availability of LA from the fortified micellar phase to the cells. It was concluded that the phase distribution of substrate and product plays a critical role in the microbiological production of CLA.

Reduction of linoleic acid inhibition in production of conjugated linoleic acid by Propionibacterium freudenreichii ssp. shermanii.

A method for the production of conjugated linoleic acid (CLA) from linoleic acid (LA) using growing cultures of Propionibacterium freudenreichii ssp. shermanii JS was developed. The growth inhibitory effect of LA was eliminated by dispersing it in a sufficient concentration of polyoxyethylene sorbitan monooleate detergent. For the whey permeate medium used, the optimum LA:detergent ratio was 1:15 (w/w). As a result, the cultures tolerated at least 1000 microg x mL(-1) LA, which was converted to CLA with 57%-87% efficiency. The cis-9, trans-11 and trans-9, cis-11 isomers constituted 85%-90% of the CLA produced. The feasibility of the method was demonstrated also in de Man Rogosa-Sharpe (MRS) broth.

Validation of a new method for patient classification, the Oulu Patient Classification.

At Vasa Central Hospital in Western Finland a further development of the Oulu Patient Classification (OPC) has been made by the development of weight coefficients and by estimating the nursing care intensity per nurse. The daily level of nursing care intensity of a ward is expressed by the number of nursing care intensity points per nurse. This article presents results from a validity test of the OPC at Vasa Central Hospital. The test was carried out by comparing the daily patient classifications by means of the OPC against measurements made by means of a new measuring instrument, the 'Professional Assessment of Optimal Nursing Care Intensity Level' (PAONCIL) developed at the Vasa Central Hospital. The study was implemented in eight wards during a period of 3 months. The data material consisted of two parts, the daily patient classifications based on the OPC (n = 19 324) and the measurements by means of the PAONCIL forms (n = 8458). Simple and multiple linear regression analyses were used as statistical methods in quantifying the linear relationship between the two interval-scaled variables. In the test of concurrent validity the coefficient of determination was 0.366, i.e. the association between these two indicators is fairly strong (36.6%). The testing of construct validity showed that the construct validity of the indicator hardly deteriorates as a result of the patients being placed in separate nursing care intensity categories. There was a clear correlation between the scores allotted by the indicator to the six different sub-areas of nursing care. When examining the construct validity of the OPC, no factors with independent explanatory power in predicting PAONCIL values were discovered other than those of the OPC. The OPC proved on the basis of this research material and these statistical methods to possess fairly adequate validity, and thus there is a good basis for further research and a development of nursing care.

Professional assessment of optimal nursing care intensity level. A new method for resource allocation as an alternative to classical time studies.

In the article a new method is presented for allocation of staff resources, 'Professional Assessment of Optimal Nursing Care Intensity Level' (PAONCIL). This method is presented as an alternative to classical time study, which has traditionally been considered to belong to systems for patient classification. By means of this method the optimal nursing care intensity level for individual wards can be established. The study comprised 8 wards, and the nurses working in these wards provided a total of 8,458 professional assessments of optimal nursing care intensity levels. The material was analysed by means of simple linear regression analysis. The nursing care intensity scores per nurse in a single ward were used as independent variables and the average PAONCIL score for the same calendar day was used as a dependent variable. The average determination coefficient for different wards were 0.37; the PAONCIL instrument thus explained 37% of the nursing care intensity/nurse variation. This corresponded to a linear correlation of 0.60. In five out of six wards for adults the optimal nursing care intensity/nurse scores were close to each other, ranging from 3.0 to 3.6. The advantage of the PAONCIL method is that it can be easily implemented in a ward, can be used time and again, is advantageous and is based on quality aspects. The PAONCIL method has been developed on the basis of a caring science perspective and can be seen as an administrative method for the nurse manager, with whose help 'good care' can become possible.

Professional assessment of optimal nursing care intensity level: a new method of assessing personnel resources for nursing care.

The primary aim of patient classification is to be able to respond to the constant variation in patients' caring needs. Systems of patient classification usually include some form of time study, e.g. work sampling or time-and-motion studies. This article deals with the pros and cons of traditional time studies and with the theoretical bases of a new method of assessing the need for staff resources for nursing, a method termed 'Professional Assessment of Optimal Nursing Care Intensity Level'. The main idea of the method is to arrive at an optimal level of nursing care intensity for a ward by means of professional assessment and daily patient classification. The optimal level of nursing care intensity is supposed to prevail when there is a balance between the patients' need for care and the hospital's staff resources. The development of this new method and an account of a pilot study carried out in two wards are presented. The results of the pilot study established that the development of the method is worth continuing in order to create an administrative tool which, by its nature, is more compatible than traditional time studies with the idea of caring from the perspective of caring science.