Comparison of central venous and arterial pH and PCO2 during open-chest CPR in the canine model

Arterial blood gases are difficult to obtain during cardiopulmonary resuscitation (CPR) in human beings, and the possibility of venous sampling is raised frequently. The reliability of central venous gases as a substitute for arterial blood gases in assessing acid base status, however, has not been investigated adequately under conditions of CPR. Therefore, femoral arterial and central venous catheters were placed in 24 mongrel dogs, and ventricular fibrillation was electrically induced. After varying predetermined downtimes from five to 60 minutes, open-chest CPR was begun, and arterial and central venous blood gases were simultaneously drawn every five minutes during a 30-minute period. Arterial pH (pHa) was consistently higher than central venous pH (pHcv) by an average of .048 units. A significant correlation existed between the pHa and pHcv at all times during CPR, with an overall r = .9771 (P less than .0001). The difference between central venous PCO2 (PcvCO2) and arterial PCO2 (PaCO2) was 5.17 mm Hg prior to cardiac arrest, but it increased 300% to a mean of 15.51 mm Hg during CPR. Correction of pHcv using conventional methods to account for this respiratory component decreased the correlation between pHa and pHcv to r = .6905. The ability of pHcv to substitute for pHa was assessed, and showed a sensitivity of 100% when pHa of 7.2 was used as a criterion for treatment. In this model, pHcv is a sensitive indicator of pHa and it may be used to guide bicarbonate therapy. The increased PcvCO2 during CPR probably results from the marked tissue lactic acid production and subsequent shift of the bicarbonate buffer into free carbon dioxide.     

Monocausal Attributions Along Cross-Sections of Psychosis Development and Links with Psychopathology and Data Gathering Style

Several attributional biases have been discussed as putative causal factors in psychosis formation and maintenance. The monocausality bias in particular describes the excessive tendency to disregard multifactorial explanations and to instead attribute events to a single cause. To elucidate the role of monocausality in psychosis development, this study compared patients with an at-risk mental state of psychosis (ARMS, n?=?49), first-episode patients (FEP, n?=?35), chronic schizophrenia patients (SZ, n?=?32) and healthy controls (HC, n?=?39) on the Internal Personal and Situational Attributions Questionnaire—Revised. FEP patients made significantly more monocausal attributions than HC to the external-personal locus for positive events. Moreover, monocausality was linked with psychotic as well as depressive symptoms and tentatively also with a hasty data gathering style. Future studies should explore associations with other metacognitive deficits and the potential to prevent or correct the monocausality bias through psychological interventions.     

Neurodegenerative Genes Polymorphisms of the -491A/T APOE,the -877T/C APP and the Risk of Primary Open-angle Glaucoma in the Polish Population

Background: Glaucoma is characterized by optic neuropathy of the retinal ganglion cell. It may be possible that β-amyloid (Aβ) and apolipoprotein E (APOE), the main proteins of the pathogenesis of AD, play a role in glaucoma development. The aim of this study was to evaluate a relationship between the APP and APOE gene polymorphisms and the risk of primary open-angle glaucoma (POAG) occurrence.

Materials and methods: The study consisted of 183 patients with POAG and 209 healthy subjects. Genomic DNA was extracted from peripheral blood. Analysis of the gene polymorphisms was performed using PCR-RFLP.

Results: We found a statistically significant increase of the -491?T allele frequency (p?=?0.02; OR?=?1.48; 95% CI?=?1.06–2.08) of APOE in POAG compared to healthy controls. There were no differences in the genotype and allele distributions and odds ratios of the APP polymorphism between patients and controls group. We also found an association between APOE polymorphic variant and retinal nerve fiber layer (RNFL). There was a statistically significant difference in the APOE gene A/T genotype frequency in the early POAG stage and middle-advanced POAG stage in comparison to the advanced POAG stage (p?=?0.04; OR?=?3.38; 95% CI?=?1.04–10.97).

Conclusions: The -491?T allele of APOE polymorphism may be associated with a risk of POAG occurrence in the Polish population.     

A patient-reported outcome measure for patients with pituitary adenoma undergoing transsphenoidal surgery

Pituitary - Pituitary adenomas affect patients’ quality-of-life (QoL) across several domains, with long-term implications even following gross-total resection or disease remission. While...     

Effects of L-thyroxine suppressive therapy on cardiac mass in patients with differentiated thyroid cancer

Patients with differentiated thyroid carcinoma (DTC) receive a life time l-thyroxine therapy in suppressive doses and may exhibit signs of cardiac hypertrophy. The aim of the study was to analyze the left ventricle mass parameters by echocardiography in patients treated with suppressive doses of thyroxine and to relate them to the possible occurrence of cardiac arrhythmias. Ninety four patients aged 19-70 years treated chronically with l-thyroxine were randomly chosen from the population of patients with DTC without concomitant diseases of circulatory system. They were divided into two subgroups according to the length of thyroxine therapy (< 60 months and > or = 60 months). Control group consisted of 41 healthy volunteers, aged 22-73 years. Heart muscle dimensions were measured by echocardiography. Left ventricle mass (LVM) and mass index (LVMI) was calculated. Electrocardiography according to Holter was carried out in 57 patients. The results of echocardiography in the whole group of patients did not differ significantly from the control group, although a tendency towards higher dimensions of the left ventricle was observed. No correlation of hormonal parameters, or thyroxine dose, with LVM or results of Holters ecg was noted. When patients were subdivided into two groups, according to the duration of therapy, significantly higher values of LVM (215 +/- 64 g versus 186 +/- 55; p < 0.05) and LVMI (114 +/- 31 g/m versus 102 +/- 23 g/m; p < 0.05) were observed in patients treated > or = 60 months in comparison to the control group. When results of Holter's ecg in patients with increased LVMI were analyzed, cardiac rhythm disturbances were stated in 50% of them, but most were of minor clinical relevance. Suppressive l-thyroxine therapy does not induce significant left heart hypertrophy during the first 5 years of treatment. Patients treated through a longer period of time should be controlled by echocardiography because of the increasing risk of the left ventricle hypertrophy and arrhythmia.     

Analysis of temporal requirements for myocardial tissue velocity imaging.

AIMS: Movements of myocardial walls include components of high velocity and short duration calling for a high sampling rate in the acquisition of tissue velocity imaging data. This study aims at establishing the optimal sampling requirements for tissue velocity imaging measurements. METHODS AND RESULTS: In 16 healthy individuals, tissue velocity imaging data were acquired at a frame rate of 141-203 frames/s for a subsequent off-line analysis using software enabling a reduction of the sampling rate to 50%, 25% and 12.5% of the initial frame rate. Different components of the myocardial velocity profile were measured at each of these frame rates. The deviation of the results from the initial values increased markedly at decreasing frame rates, producing an underestimation of peak systolic and diastolic velocities, most other measured parameters being overestimated. A cut-off point for an acceptable < or =10% deviation of the results corresponded to at least 70 frames/s for peak systolic and early diastolic velocity, and to at least 100 frames/s for other systolic and diastolic parameters. CONCLUSION: A high sampling rate is essential for a proper rendering of tissue velocity imaging signals, too low frame rates resulting in inferior accuracy of the results. This should be kept in mind while viewing reported tissue velocity imaging data.     

Studies in experimental animals on disseminated intravascular coagulation (DIC).

Changes in the clotting system, as well as morphological and functional alterations corresponding to that of the pathologic phenomenon of disseminated intravascular coagulation (DIC) or consumption coagulopathy, were produced by thrombin infusion (550 NIH U X kg-1 X h-1) in rats and simultaneous inhibition of fibrinolysis by PAMBA (100 mg/kg). Changes in the fibrinogen level and platelet count as well as the appearances of fibrin monomers and the formation of microthrombi in several organs were evaluated. Simultaneously, the function of the respiratory system was investigated by continuous measurement of oxygen consumption as well as elasticity and water content of the lung. From the time course of the alterations in the several parameters, conclusions can be drawn for the pathogenesis and the possible therapeutic influence on DIC.