Clinical review: Practical recommendations on the management of perioperative heart failure in cardiac surgery

Acute cardiovascular dysfunction occurs perioperatively in more than 20% of cardiosurgical patients, yet current acute heart failure (HF) classification is not applicable to this period. Indicators of major perioperative risk include unstable coronary syndromes, decompensated HF, significant arrhythmias and valvular disease. Clinical risk factors include history of heart disease, compensated HF, cerebrovascular disease, presence of diabetes mellitus, renal insufficiency and high-risk surgery. EuroSCORE reliably predicts perioperative cardiovascular alteration in patients aged less than 80 years. Preoperative B-type natriuretic peptide level is an additional risk stratification factor. Aggressively preserving heart function during cardiosurgery is a major goal. Volatile anaesthetics and levosimendan seem to be promising cardioprotective agents, but large trials are still needed to assess the best cardioprotective agent(s) and optimal protocol(s). The aim of monitoring is early detection and assessment of mechanisms of perioperative cardiovascular dysfunction. Ideally, volume status should be assessed by 'dynamic' measurement of haemodynamic parameters. Assess heart function first by echocardiography, then using a pulmonary artery catheter (especially in right heart dysfunction). If volaemia and heart function are in the normal range, cardiovascular dysfunction is very likely related to vascular dysfunction. In treating myocardial dysfunction, consider the following options, either alone or in combination: low-to-moderate doses of dobutamine and epinephrine, milrinone or levosimendan. In vasoplegia-induced hypotension, use norepinephrine to maintain adequate perfusion pressure. Exclude hypovolaemia in patients under vasopressors, through repeated volume assessments. Optimal perioperative use of inotropes/vasopressors in cardiosurgery remains controversial, and further large multinational studies are needed. Cardiosurgical perioperative classification of cardiac impairment should be based on time of occurrence (precardiotomy, failure to wean, postcardiotomy) and haemodynamic severity of the patient's condition (crash and burn, deteriorating fast, stable but inotrope dependent). In heart dysfunction with suspected coronary hypoperfusion, an intra-aortic balloon pump is highly recommended. A ventricular assist device should be considered before end organ dysfunction becomes evident. Extra-corporeal membrane oxygenation is an elegant solution as a bridge to recovery and/or decision making. This paper offers practical recommendations for management of perioperative HF in cardiosurgery based on European experts' opinion. It also emphasizes the need for large surveys and studies to assess the optimal way to manage perioperative HF in cardiac surgery.     

Assessing the knowledge of bronchial asthma among primary health care physicians in Crete: A pre- and post-test following an educational course

Aim  

To assess the level of knowledge for bronchial asthma of the primary healthcare physicians serving a rural population on the island of Crete, both before and immediately after a one-day educational course.     

Peroxisome proliferator-activated receptor-γ protects ERBB2-positive breast cancer cells from palmitate toxicity

Introduction  

Accumulation of fatty acids and neutral lipids in nonadipose tissues is cytotoxic. We recently showed that ERBB2-positive breast cancer cells produce significantly high amounts of fats, because of overexpression of the peroxisome proliferator-activated receptor (PPAR)γ-binding protein and the nuclear receptor NR1D1 (nuclear receptor subfamily 1, group D, member 1; Rev-erbα). These genes upregulate de novo fatty acid synthesis, which is a critical pathway for the energy production and survival of these cells. NR1D1 and PPARγ-binding protein are functionally related to PPARγ, a well established positive regulator of adipogenesis and lipid storage.     

Assessment of iron distribution between liver,spleen, pancreas,bone marrow,and myocardium by means of R2 relaxometry with MRI in patients with β‐thalassemia major

Purpose

To investigate the correlation between the degree of hepatic, splenic, pancreatic, vertebral bone marrow (VBM), and myocardial siderosis, as expressed by relaxation rate (R2 = 1/T2) values, in patients with thalassemia.

Materials and Methods

R2 relaxation rate values of liver, spleen, VBM, pancreas, and myocardium were estimated in 68 consecutive transfusion‐dependent patients with β‐thalassemia major and 10 healthy controls using a respiratory triggered 16‐echo Carr‐Purcell‐Meiboom‐Gill (CPMG) spin echo sequence.

Results

Hepatic R2 values were significantly increased in all 68 patients; VBM, pancreatic, and myocardial R2 values were increased in 67/68, 35/47, and 47/61 patients, whereas five patients showed decreased pancreatic R2 attributed to fatty degeneration. Of the 39 nonsplenectomized patients, splenic R2 values were decreased in 30 and normal in nine patients. Hepatic R2 values correlated with splenic (r = 0.63, P < 0.001), VBM (r = 0.52, P < 0.001), but not with myocardial and pancreatic R2 values.

Conclusion

Despite positive correlations between the degree of hepatic, splenic, and VBM siderosis, as expressed by respective R2 values, there was variability of iron distribution patterns in thalassemic patients. Unpredictable patterns of iron distribution may be seen, such as normal signal of the spleen in the presence of siderotic liver, resembling primary hemochromatosis. Fatty degeneration of the pancreas was not uncommon. J. Magn. Reson. Imaging 2009;29:853–859. © 2009 Wiley‐Liss, Inc.     

Stability and antibacterial potency of ceftazidime and vancomycin eyedrops reconstituted in BSS® against Pseudomonas aeruginosa and Staphylococcus aureus

Purpose: We aimed to study the stability and the in vitro antibacterial potency of ceftazidime and vancomycin eyedrops against Pseudomonas aeruginosa and Staphylococcus aureus, respectively, under different storage temperatures and light conditions. Methods: Solutions of ceftazidime 50 mg/ml and vancomycin 50 mg/ml were prepared by reconstituting with balanced salt solution (BSS^®) and stored at 4 °C and at 24 °C with and without exposure to light. The minimum bactericidal concentrations against P. aeruginosa and S. aureus were measured to evaluate the antimicrobial potency over a 4‐week period. Changes in the pH values and physical characteristics of the solutions were recorded over the same period of time. Results: The antibacterial potency of ceftazidime decreased significantly from days 3 and 7 onwards at storage temperatures of 24 °C and 4 °C, respectively, but was not affected by light exposure. The pH value progressed from acidic to alkaline, peaking at day 3, in all solutions. The antibacterial potency of vancomycin remained stable during the 4‐week period, but its pH showed a slight progression from acidic to less acidic, in all solutions. Conclusions: Ceftazidime eyedrops in BSS^® appear to remain effective against P. aeruginosa for ≥ 7 days when stored at 4 °C, but were less effective when stored at 24 °C. Loss of antibacterial potency coincides with the appearance of visual and olfactory signs of degradation. The transient rise in pH at day 3 is a matter of possible concern, however, as it may affect patient tolerance. By contrast, vancomycin eyedrops in BSS^® can be safely used for ≥ 4 weeks, stored at either 4 °C or 24 °C.     

Correlation of transiently evoked to distortion-product otoacoustic emission measures in healthy children

OBJECTIVE: Transiently evoked (TEOAEs) and distortion-product otoacoustic emissions at the 2f1-f2 frequency (DPOAEs) are being used as a clinical tool for diagnosis of peripheral auditory pathology. Because both tests are fast and non-invasive, they may be an excellent method for hearing screening in infants and children. The purpose of this study was to compare the TEOAE and DPOAE measures obtained in a group of healthy children. METHODS: Sixty-six school-aged children with normal hearing were included in the study. Subjects with recent otologic disease or abnormal tympanograms were excluded. TEOAEs and DPOAEs were performed using a DP Echoport ILO 292 Otodynamics analyzer connected to a portable personal computer. Correlation between TEOAE amplitudes and DPOAE levels was estimated. RESULTS: Correlation between TEOAE amplitudes and DPOAE levels was highly significant across all measured frequencies. Correlation was more significant at the middle frequencies than at the low and high frequencies. CONCLUSIONS: Although frequency specific information may be obtained by both tests, most reliable results were obtained at the middle frequencies. TEOAE values were more prominent at low frequencies, whereas DPOAEs were more effective at high frequencies. Both methods are reliable, objective, fast and useful tests of the cochlear status and should be included in the standard audiological diagnostic work-up of children.     

Hybrid Simulation Combining a High Fidelity Scenario with a Pelvic Ultrasound Task Trainer Enhances the Training and Evaluation of Endovaginal Ultrasound Skills

Objectives: In this study, an endovaginal ultrasound (US) task trainer was combined with a high‐fidelity US mannequin to create a hybrid simulation model. In a scenario depicting a patient with ectopic pregnancy and hemorrhagic shock, this model was compared with a standard high‐fidelity simulation during training sessions with emergency medicine (EM) residents. The authors hypothesized that use of the hybrid model would increase both the residents’ self‐reported educational experience and the faculty’s self‐reported ability to evaluate the residents’ skills. Methods: A total of 45 EM residents at two institutions were randomized into two groups. Each group was assigned to one of two formats involving an ectopic pregnancy scenario. One format incorporated the new hybrid model, in which residents had to manipulate an endovaginal US probe in a task trainer; the other used the standard high‐fidelity simulation mannequin together with static photo images. After finishing the scenario, residents self‐rated their overall learning experience and how well the scenario evaluated their ability to interpret endovaginal US images. Faculty members reviewed video recordings of the other institution’s residents and rated their own ability to evaluate residents’ skills in interpreting endovaginal US images and diagnosing and managing the case scenario. Visual analog scales (VAS) were used for the self‐ratings. Results: Compared to the residents assigned to the standard simulation scenario, residents assigned to the hybrid model reported an increase in their overall educational experience (Δ VAS = 10, 95% confidence interval [CI] = 4 to 18) and felt the hybrid model was a better measure of their ability to interpret endovaginal US images (Δ VAS = 17, 95% CI = 7 to 28). Faculty members found the hybrid model to be better than the standard simulation for evaluating residents’ skills in interpreting endovaginal US images (Δ VAS = 13, 95% CI = 6 to 20) and diagnosing and managing the case (Δ VAS = 10, 95% CI = 2 to 18). Time to reach a diagnosis was similar in both groups (p = 0.053). Conclusions: Use of a hybrid simulation model combining a high‐fidelity simulation with an endovaginal US task trainer improved residents’ educational experience and improved faculty’s ability to evaluate residents’ endovaginal US and clinical skills. This novel hybrid tool should be considered for future education and evaluation of EM residents.     

Association of HLA-DQ Heterodimer Residues −18β and β57 With Progression From Islet Autoimmunity to Diabetes in the Diabetes Prevention Trial–Type 1

OBJECTIVEThe purpose was to test the hypothesis that the HLA-DQαβ heterodimer structure is related to the progression of islet autoimmunity from asymptomatic to symptomatic type 1 diabetes (T1D).RESEARCH DESIGN AND METHODSNext-generation targeted sequencing was used to genotype HLA-DQA1-B1 class II genes in 670 subjects in the Diabetes Prevention Trial–Type 1 (DPT-1). Coding sequences were translated into DQ α- and β-chain amino acid residues and used in hierarchically organized haplotype (HOH) association analysis to identify motifs associated with diabetes onset.RESULTSThe opposite diabetes risks were confirmed for HLA DQA1*03:01-B1*03:02 (hazard ratio [HR] 1.36; P = 2.01 ∗ 10⁻³) and DQA1*03:03-B1*03:01 (HR 0.62; P = 0.037). The HOH analysis uncovered residue −18β in the signal peptide and β57 in the β-chain to form six motifs. DQ*VA was associated with faster (HR 1.49; P = 6.36 ∗ 10⁻⁴) and DQ*AD with slower (HR 0.64; P = 0.020) progression to diabetes onset. VA/VA, representing DQA1*03:01-B1*03:02 (DQ8/8), had a greater HR of 1.98 (P = 2.80 ∗ 10⁻³). The DQ*VA motif was associated with both islet cell antibodies (P = 0.023) and insulin autoantibodies (IAAs) (P = 3.34 ∗ 10⁻³), while the DQ*AD motif was associated with a decreased IAA frequency (P = 0.015). Subjects with DQ*VA and DQ*AD experienced, respectively, increasing and decreasing trends of HbA_1c levels throughout the follow-up.CONCLUSIONSHLA-DQ structural motifs appear to modulate progression from islet autoimmunity to diabetes among at-risk relatives with islet autoantibodies. Residue −18β within the signal peptide may be related to levels of protein synthesis and β57 to stability of the peptide-DQab trimolecular complex.