Teleconsultation for preoperative evaluation during the coronavirus disease 2019 pandemic: A technical and medical feasibility study.

BACKGROUND: During the surge in coronavirus disease 2019 (COVID-19) infections in early 2020, many medical organisations began developing strategies for implementing teleconsultation to maintain medical services during lockdown and to limit physical contact. Therefore, we developed a teleconsultation preoperative evaluation platform to replace on-site preoperative meetings. OBJECTIVE: This study assessed the feasibility of a teleconsultation for preoperative evaluation and procedure-associated adverse events. DESIGN: Implementation study. SETTING: A tertiary care university hospital in Germany from April 2020 to October 2020. PATIENTS: One hundred and eleven patients scheduled for elective surgery. INTERVENTION: Patients were assigned to receive teleconsultation for preoperative evaluation and to complete a subsequent survey. MAIN OUTCOME MEASURES: Primary endpoints were medical and technical feasibility, user satisfaction and time savings. RESULTS: For 100 out of 111 patients, telepreoperative consultations allowed for adequate perioperative risk assessment, patient education and also for effective collection of legal signatures. For six patients (5.4%), consultations could not be started because of technical issues, whereas for five patients (4.8%), clearance for surgery could not be granted because of medical reasons. A clear majority of anaesthetists (93.7%) rated the telepreoperative evaluations as equivalent to on-site meetings. The majority of the patients considered teleconsultation for preoperative evaluation as convenient as an on-site meeting (98.2%) and would choose a teleconsultation again (97.9%). Median travel time saved by patients was 60 min (Q1 40, Q3 80). We registered one adverse event: we detected atrial fibrillation in one patient only immediately prior to surgery. CONCLUSION: Telepreoperative evaluations are medically and technically feasible, yielding high satisfaction rates on both sides. However, regarding patient safety, not every patient is equally well suited. Overall, implementation of teleconsultation for preoperative evaluation into clinical routine could help maintain medical care during the COVID-19 pandemic. TRIAL REGISTRATION: NCT04518514, ClinicalTrials.gov.

Inhaled nitric oxide preserves ventricular function during resuscitation using a percutaneous mechanical circulatory support device in a porcine cardiac arrest model: an echocardiographic myocardial work analysis.

BACKGROUND: Resuscitation using a percutaneous mechanical circulatory support device (iCPR) improves survival after cardiac arrest (CA). We hypothesized that the addition of inhaled nitric oxide (iNO) during iCPR might prove synergistic, leading to improved myocardial performance due to lowering of right ventricular (RV) afterload, left ventricular (LV) preload, and myocardial energetics. This study aimed to characterize the changes in LV and RV function and global myocardial work indices (GWI) following iCPR, both with and without iNO, using 2-D transesophageal echocardiography (TEE) and GWI evaluation as a novel non-invasive measurement. METHODS: In 10 pigs, iCPR was initiated following electrically-induced CA and 10 min of untreated ventricular fibrillation (VF). Pigs were randomized to either 20 ppm (20 ppm, n = 5) or 0 ppm (0 ppm, n = 5) of iNO in addition to therapeutic hypothermia for 5 h following ROSC. All animals received TEE at five pre-specified time-points and invasive hemodynamic monitoring. RESULTS: LV end-diastolic volume (LVEDV) increased significantly in both groups following CA. iCPR alone led to significant LV unloading at 5 h post-ROSC with LVEDV values reaching baseline values in both groups (20 ppm: 68.2 ± 2.7 vs. 70.8 ± 6.1 mL, p = 0.486; 0 ppm: 70.8 ± 1.3 vs. 72.3 ± 4.2 mL, p = 0.813, respectively). LV global longitudinal strain (GLS) increased in both groups following CA. LV-GLS recovered significantly better in the 20 ppm group at 5 h post-ROSC (20 ppm: - 18 ± 3% vs. 0 ppm: - 13 ± 2%, p = 0.025). LV-GWI decreased in both groups after CA with no difference between the groups. Within 0 ppm group, LV-GWI decreased significantly at 5 h post-ROSC compared to baseline (1,125 ± 214 vs. 1,835 ± 305 mmHg%, p = 0.011). RV-GWI was higher in the 20 ppm group at 3 h and 5 h post-ROSC (20 ppm: 189 ± 43 vs. 0 ppm: 108 ± 22 mmHg%, p = 0.049 and 20 ppm: 261 ± 54 vs. 0 ppm: 152 ± 42 mmHg%, p = 0.041). The blood flow calculated by the Impella controller following iCPR initiation correlated well with the pulsed-wave Doppler (PWD) derived pulmonary flow (PWD vs. controller: 1.8 ± 0.2 vs. 1.9 ± 0.2L/min, r = 0.85, p = 0.012). CONCLUSIONS: iCPR after CA provided sufficient unloading and preservation of the LV systolic function by improving LV-GWI recovery. The addition of iNO to iCPR enabled better preservation of the RV-function as determined by better RV-GWI. Additionally, Impella-derived flow provided an accurate measure of total flow during iCPR.

Effects of inhaled nitric oxide on outcome after prolonged cardiac arrest in mild therapeutic hypothermia treated rats.

Guidelines endorse targeted temperature management to reduce neurological sequelae and mortality after cardiac arrest (CA). Additional therapeutic approaches are lacking. Inhaled nitric oxide (iNO) given post systemic ischemia/reperfusion injury improves outcomes. Attenuated inflammation by iNO might be crucial in brain protection. iNO augmented mild therapeutic hypothermia (MTH) may improve outcome after CA exceeding the effect of MTH alone. Following ten minutes of CA and three minutes of cardiopulmonary resuscitation, 20 male Sprague-Dawley rats were randomized to receive MTH at 33 °C for 6hrs or MTH + 20ppm iNO for 5hrs; one group served as normothermic control. During the experiment blood was taken for biochemical evaluation. A neurological deficit score was calculated daily for seven days post CA. On day seven, brains and hearts were harvested for histological evaluation. Treatment groups showed a significant decrease in lactate levels six hours post resuscitation in comparison to controls. TNF-α release was significantly lower in MTH + iNO treated animals only at four hours post ROSC. While only the combination of MTH and iNO improved neurological function in a statistically significant manner in comparison to controls on days 4-7 after CA, there was no significant difference between groups treated with MTH and MTH + iNO.

Calcification of Vascular Smooth Muscle Cells and Imaging of Aortic Calcification and Inflammation.

Cardiovascular disease is the leading cause of morbidity and mortality in the world. Atherosclerotic plaques, consisting of lipid-laden macrophages and calcification, develop in the coronary arteries, aortic valve, aorta, and peripheral conduit arteries and are the hallmark of cardiovascular disease. In humans, imaging with computed tomography allows for the quantification of vascular calcification; the presence of vascular calcification is a strong predictor of future cardiovascular events. Development of novel therapies in cardiovascular disease relies critically on improving our understanding of the underlying molecular mechanisms of atherosclerosis. Advancing our knowledge of atherosclerotic mechanisms relies on murine and cell-based models. Here, a method for imaging aortic calcification and macrophage infiltration using two spectrally distinct near-infrared fluorescent imaging probes is detailed. Near-infrared fluorescent imaging allows for the ex vivo quantification of calcification and macrophage accumulation in the entire aorta and can be used to further our understanding of the mechanistic relationship between inflammation and calcification in atherosclerosis. Additionally, a method for isolating and culturing animal aortic vascular smooth muscle cells and a protocol for inducing calcification in cultured smooth muscle cells from either murine aortas or from human coronary arteries is described. This in vitro method of modeling vascular calcification can be used to identify and characterize the signaling pathways likely important for the development of vascular disease, in the hopes of discovering novel targets for therapy.

Dose dependent neuroprotection of the noble gas argon after cardiac arrest in rats is not mediated by K(ATP)-channel opening.

PURPOSE: Argon at a dosage of 70% is neuroprotective when given 1 h after cardiac arrest (CA) in rats. In a rodent model, we investigated if the neuroprotective effects of argon are dose dependent and mediated by adenosine triphosphate dependent potassium (K(ATP)) channels. METHODS: Forty-seven male Sprague-Dawley rats were subjected to 7 min of CA and 3 min of cardiopulmonary resuscitation (CPR). In protocol I animals were randomized to receive either 70% or 40% argon ventilation 1 h after successful CPR or no argon-treatment. Animals of the second protocol also received 1 h of 70% argon ventilation or no argon treatment but were randomized to a group receiving the K(ATP) channel blocker 5-hydroxydecanoate (5-HD). For all animals a neurological deficit score (NDS) was calculated daily for seven days following the experiment before the animals were killed and the brains harvested for histopathological analyses. RESULTS: All animals survived. Control animals exhibited severe neurologic dysfunction at all points in time as measured with the NDS. Argon treated animals showed significant improvements in the NDS through all postoperative days in a dose dependent fashion. This was paralleled by a significant reduction in the neuronal damage index in the neocortex and the hippocampal CA 3/4 region. Administration of 5-HD neither abolished the positive effects on functional recovery nor on histopathologic changes observed in the argon group. CONCLUSION: Our study demonstrates a dose dependent neuroprotective effect of argon administration in this rodent model, which is not mediated via ATP dependent potassium channels.

Inhibition of bone morphogenetic protein signaling reduces vascular calcification and atherosclerosis.

OBJECTIVE: The expression of bone morphogenetic proteins (BMPs) is enhanced in human atherosclerotic and calcific vascular lesions. Although genetic gain- and loss-of-function experiments in mice have supported a causal role of BMP signaling in atherosclerosis and vascular calcification, it remains uncertain whether BMP signaling might be targeted pharmacologically to ameliorate both of these processes. METHODS AND RESULTS: We tested the impact of pharmacological BMP inhibition on atherosclerosis and calcification in LDL receptor-deficient (LDLR-/-) mice. LDLR-/- mice fed a high-fat diet developed abundant vascular calcification within 20 weeks. Prolonged treatment of LDLR-/- mice with the small molecule BMP inhibitor LDN-193189 was well-tolerated and potently inhibited development of atheroma, as well as associated vascular inflammation, osteogenic activity, and calcification. Administration of recombinant BMP antagonist ALK3-Fc replicated the antiatherosclerotic and anti-inflammatory effects of LDN-193189. Treatment of human aortic endothelial cells with LDN-193189 or ALK3-Fc abrogated the production of reactive oxygen species induced by oxidized LDL, a known early event in atherogenesis. Unexpectedly, treatment of mice with LDN-193189 lowered LDL serum cholesterol by 35% and markedly decreased hepatosteatosis without inhibiting HMG-CoA reductase activity. Treatment with BMP2 increased, whereas LDN-193189 or ALK3-Fc inhibited apolipoprotein B100 secretion in HepG2 cells, suggesting that BMP signaling contributes to the regulation of cholesterol biosynthesis. CONCLUSION: These results definitively implicate BMP signaling in atherosclerosis and calcification, while uncovering a previously unidentified role for BMP signaling in LDL cholesterol metabolism. BMP inhibition may be helpful in the treatment of atherosclerosis and associated vascular calcification.