Ventricular Arrhythmia Precipitated by Severe Hypocalcaemia Secondary to Primary Hypoparathyroidism

Sequelae and Comorbidities of COVID-19 Manifestations on the Cardiac and the Vascular Systems

COVID-19 patients with pre-existing cardiovascular conditions are at greater risk of severe illness due to the SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) virus. This review evaluates the highest risk factors for these patients, not limited to pre-existing hypertension, cardiac arrhythmias, hypercoagulation, ischemic heart disease, and a history of underlying heart conditions. SARS-CoV-2 may also precipitate de novo cardiac complications. The interplay between existing cardiac conditions and de novo cardiac complications is the focus of this review. In particular, SARS-CoV-2 patients present with hypercoagulation conditions, cardiac arrhythmias, as significant complications. Also, cardiac arrhythmias are another well-known cardiovascular-related complication seen in COVID-19 infections and merit discussion in this review. Amid the pandemic, myocardial infarction (MI) has been reported to a high degree in SARS-CoV-2 patients. Currently, the specific causative mechanism of the increased incidence of MI is unclear. However, studies suggest several links to high angiotensin-converting enzyme 2 (ACE2) expression in myocardial and endothelial cells, systemic hyper-inflammation, an imbalance between myocardial oxygen supply and demand, and loss of ACE2-mediated cardio-protection. Furthermore, hypertension and SARS-CoV-2 infection patients’ prognosis has shown mixed results across current studies. For this reason, an in-depth analysis of the interactions between SARS-CoV2 and the ACE2 cardio-protective mechanism is warranted. Similarly, ACE2 receptors are also expressed in the cerebral cortex tissue, both in neurons and glia. Therefore, it seems very possible for both cardiovascular and cerebrovascular systems to be damaged leading to further dysregulation and increased risk of mortality risk. This review aims to discuss the current literature related to potential complications of COVID-19 infection with hypertension and the vasculature, including the cervical one. Finally, age is a significant prognostic indicator among COVID-19 patients. For a mean age group of 70 years, the main presenting symptoms include fever, shortness of breath, and a persistent cough. Elderly patients with cardiovascular comorbidities, particularly hypertension and diabetes, represent a significant group of critical cases with increased case fatality rates. With the current understanding of COVID-19, it is essential to explore the mechanisms by which SARS-CoV-2 operates to improve clinical outcomes for patients suffering from underlying cardiovascular diseases and reduce the risk of such conditions de novo.

Regional citrate anticoagulation "non-shock" protocol with pre-calculated flow settings for patients with at least 6 L/hour liver citrate clearance

BACKGROUND

Regional citrate anticoagulation (RCA) for the prevention of clotting of the extracorporeal blood circuit during continuous kidney replacement therapy (CKRT) has been employed in limited fashion because of the complexity and complications associated with certain protocols. Hypertonic citrate infusion to achieve circuit anticoagulation results in variable systemic citrate- and sodium load and increases the risk of citrate accumulation and hypernatremia. The practice of "single starting calcium infusion rate for all patients" puts patients at risk for clinically significant hypocalcemia if filter effluent calcium losses exceed replacement. A fixed citrate to blood flow ratio, personalized effluent and pre-calculated calcium infusion dosing based on tables derived through kinetic analysis enable providers to use continuous veno-venous hemo-diafiltration (CVVHDF)-RCA in patients with liver citrate clearance of at least 6 L/h.

METHODS

This was a single-center prospective observational study conducted in intensive care unit patients triaged to be treated with the novel pre-calculated CVVHDF-RCA "Non-shock" protocol. RCA efficacy outcomes were time to first hemofilter loss and circuit ionized calcium (iCa) levels. Safety outcomes were surrogate of citrate accumulation (TCa/iCa ratio) and the incidence of acid-base and electrolyte complications.

RESULTS

Of 53 patients included in the study, 31 (59%) had acute kidney injury and 12 (22.6%) had the diagnosis of cirrhosis at the start of CVVHDF-RCA. The median first hemofilter life censored for causes other than clotting exceeded 70 h. The cumulative incidence of hypernatremia (Na > 148 mM), metabolic alkalosis (HCO3- > 30 mM), hypocalcemia (iCa < 0.9 mM) and hypercalcemia (iCa > 1.5 mM) were 1/47 (1%), 0/50 (0%), 1/53 (2%), 1/53 (2%) respectively and were not clinically significant. The median (25th-75th percentile) of the highest TCa/iCa ratio for every 24-h interval on CKRT was 1.99 (1.91-2.13).

CONCLUSIONS

The fixed citrate to blood flow ratio, as opposed to a titration approach, achieves adequate circuit iCa (< 0.4 mm/L) for any hematocrit level and plasma flow. The personalized dosing approach for calcium supplementation based on pre-calculated effluent calcium losses as opposed to the practice of "one starting dose for all" reduces the risk of clinically significant hypocalcemia. The fixed flow settings achieve clinically desirable steady state systemic electrolyte levels.

Endocrine myopathies: clinical and histopathological features of the major forms

Endocrinopathies, such as thyroid and parathyroid diseases, disorders of the adrenal axis, and acromegaly are included among the many causes of myopathy. Muscle disturbances caused by endocrine disorders are mainly due to alterations in the protein and carbohydrate metabolisms. Either a deficiency or excess of hormones produced by the glands can cause muscle dysfunction that can be reversed by starting hormone replacement therapy or acting on hormone dysfunction. The diagnosis is usually easy if a muscle disorder occurs in an overt endocrinopathy; however, in few patients, myopathy could be the first manifestation of the underlying endocrinopathy. In this article we discuss pathophysiology, clinical features and management of muscle involvement related to the major endocrine diseases.