Control of hypertension in the critically ill: a pathophysiological approach

Left ventricle mass index in paediatric intensive care unit acquired hypertension

BACKGROUND

Hypertension acquired in paediatric critical patients is a recognised challenge, with variable reported frequency. Pain, agitation, and/or medications such as beta stimulants and corticosteroids are well-known risk factors. Sympathomimetics in septic patients can cause high blood pressure, especially with unobserved haemodynamic monitors. Beyond haemodynamic factors, several endocrinal-metabolic factors - including catecholamines, insulin, renin, angiotensin, the aldosterone system, and sodium consumption - may contribute to the left ventricular growth. It is well known that the sympathetic tone has a trophic effect on the heart muscle.

METHOD

A prospective cohort study was conducted during the year 2021. The children were divided into two groups: those who were critically ill with paediatric intensive care unit-acquired hypertension (n = 59) and those without paediatric intensive care unit-acquired hypertension (n = 62). We used the American Academy of Pediatrics' 2017 definition of hypertension to diagnose paediatric intensive care unit-acquired hypertension. Measurement of cardiac output and systemic vascular resistance was performed by cardiometry. Left ventricular myocardial performance and left ventricular mass index were measured by bedside echocardiography at the onset of hypertension diagnosis.

RESULTS

Critically ill children with acquired hypertension had a higher cardiac index (p = 0.0001), systemic vascular resistance index (<0.0001), myocardial performance (0.037), and left ventricular mass index (0.009). The longer duration of stay observed in the hypertension group had no observable effect on mortality (<0.0001).

CONCLUSION

Both myocardial performance and left ventricle mass index increased in critically ill children with paediatric intensive care unit-acquired hypertension.

Catecholamine-induced hypertensive crises: current insights and management

Phaeochromocytomas and paragangliomas (PPGLs) release catecholamines leading to catecholamine-induced hypertensive (CIH) crises, with blood pressure greater than or equal to 180/120 mm Hg. CIH crises can be complicated by tachyarrhythmias, hypotension, or life-threatening target organ damage while treatment remains undefined, often requiring co-management between endocrinologists and cardiologists. Furthermore, biochemical diagnosis of a PPGL as a cause of a CIH crisis can be difficult to identify or confounded by comorbid conditions, potentially resulting in misdiagnosis. Here, we combine relevant evidence, 60 years of collective clinical experience, insights derived from assessing over 2600 patients with PPGL, and supplementary outcomes from 100 patients (treated at the National Institutes of Health) with a CIH crisis to inform diagnosis and treatment of CIH crises. Recognising that disparities exist between availability, cost, and familiarity of various agents, flexible approaches are delineated allowing for customisation, given institutional availability and provider preference. A CIH crisis and its complications are readily treatable with available drugs, with effective intervention defining an avenue for mitigating consequent morbidity and mortality in patients with PPGL.

Hypoxia Associated With Dihydropyridine Calcium Channel Inhibitors: A Pharmacovigilance Study in VigiBase

Due to their negative effects on hypoxic pulmonary vasoconstriction, dihydropyridine calcium channel inhibitors (DCCIs) can lead to hypoxia in patients with a pulmonary shunt. To date, only preclinical studies and case reports have focused on this potential adverse drug reaction. We aimed to assess the reporting association between DCCIs and hypoxia using the World Health Organization pharmacovigilance database (VigiBase). We performed a disproportionality analysis to evaluate the strength of the reporting association between i.v. clevidipine and nicardipine, thought to be a surrogate of patients in the intensive care unit, and hypoxia. The information component and the lower end of its 95% credibility interval were used to evaluate disproportionality. A description of the cases was made. Secondary outcomes included the association between all DCCIs and hypoxia compared with other treatments with similar indications, urapidil and labetalol, regardless of the route of administration. Association between oral nicardipine and hypoxia was also searched. A statistically significant signal of hypoxia was found for intravenous clevidipine and nicardipine. The time to onset was reported with a median of 2 days (interquartile range 1.5-4.5). Four dechallenges were performed with intravenous nicardipine, leading to the resolution of the symptoms. Regardless of the route of administration, a signal of hypoxia was also found for nimodipine but not for other drugs, including comparators. For nicardipine no signal of hypoxia was found with the oral route of administration. Our pharmacovigilance database analysis showed a significant association between the use of intravenous DCCIs and hypoxia.

Nicardipine-induced acute respiratory failure: Case report and literature review

Hypoxic pulmonary vasoconstriction (HPV) is a major physiological mechanism that prevents the development of hypoxemia secondary to a regional decrease in the ventilation-perfusion ratio (the intrapulmonary shunt effect). Calcium plays a critical role in the cellular response to hypoxia and the regulation of the pulmonary vascular tone. Therefore, calcium channel antagonists such as nicardipine have the potential to interfere with the pulmonary response to hypoxia, increasing intrapulmonary blood shunt and thus worsening underlying hypoxemia. This article reports the case of a 40-year-old man suffering from lobar pneumonia, who developed a rapidly progressing hypoxemia after starting nicardipine infusion for blood pressure control. After ruling out all major causes of hypoxemic respiratory failure, the involvement of the calcium channel antagonist was strongly suspected. Hypoxemia caused by HPV release is an underreported side effect of calcium channel blockers. There are few clinical reports that describe the occurrence of this adverse event, and to our knowledge, only one other publication describes a patient suffering from infectious pneumopathy. In this article, we discuss the cellular mechanisms behind the HPV, as well as the pharmacology of calcium channel antagonists and their involvement in the development of acute respiratory failure. The purpose of this report is to remind clinicians dealing with patients affected by acute hypoxemia that pharmacologic HPV inhibition should be considered as part of the differential diagnosis, thus avoiding unnecessary costly and time-consuming assessments.

Optimal dynamic treatment regime estimation using information extraction from unstructured clinical text

The wide-scale adoption of electronic health records (EHRs) provides extensive information to support precision medicine and personalized health care. In addition to structured EHRs, we leverage free-text clinical information extraction (IE) techniques to estimate optimal dynamic treatment regimes (DTRs), a sequence of decision rules that dictate how to individualize treatments to patients based on treatment and covariate history. The proposed IE of patient characteristics closely resembles "The clinical Text Analysis and Knowledge Extraction System" and employs named entity recognition, boundary detection, and negation annotation. It also utilizes regular expressions to extract numerical information. Combining the proposed IE with optimal DTR estimation, we extract derived patient characteristics and use tree-based reinforcement learning (T-RL) to estimate multistage optimal DTRs. IE significantly improved the estimation in counterfactual outcome models compared to using structured EHR data alone, which often include incomplete data, data entry errors, and other potentially unobserved risk factors. Moreover, including IE in optimal DTR estimation provides larger study cohorts and a broader pool of candidate tailoring variables. We demonstrate the performance of our proposed method via simulations and an application using clinical records to guide blood pressure control treatments among critically ill patients with severe acute hypertension. This joint estimation approach improves the accuracy of identifying the optimal treatment sequence by 14-24% compared to traditional inference without using IE, based on our simulations over various scenarios. In the blood pressure control application, we successfully extracted significant blood pressure predictors that are unobserved or partially missing from structured EHR.

Machine Learning and Artificial Intelligence in Neurocritical Care: a Specialty-Wide Disruptive Transformation or a Strategy for Success

PURPOSE OF REVIEW

Neurocritical care combines the complexity of both medical and surgical disease states with the inherent limitations of assessing patients with neurologic injury. Artificial intelligence (AI) has garnered interest in the basic management of these complicated patients as data collection becomes increasingly automated.

RECENT FINDINGS

In this opinion article, we highlight the potential AI has in aiding the clinician in several aspects of neurocritical care, particularly in monitoring and managing intracranial pressure, seizures, hemodynamics, and ventilation. The model-based method and data-driven method are currently the two major AI methods for analyzing critical care data. Both are able to analyze the vast quantities of patient data that are accumulated in the neurocritical care unit. AI has the potential to reduce healthcare costs, minimize delays in patient management, and reduce medical errors. However, these systems are an aid to, not a replacement for, the clinician's judgment.

Artificial intelligence in neurocritical care

BACKGROUND

Neurocritical care combines the management of extremely complex disease states with the inherent limitations of clinically assessing patients with brain injury. As the management of neurocritical care patients can be immensely complicated, the automation of data-collection and basic management by artificial intelligence systems have garnered interest.

METHODS

In this opinion article, we highlight the potential artificial intelligence has in monitoring and managing several aspects of neurocritical care, specifically intracranial pressure, seizure monitoring, blood pressure, and ventilation.

RESULTS

The two major AI methods of analytical technique currently exist for analyzing critical care data: the model-based method and data driven method. Both of these methods have demonstrated an ability to analyze vast quantities of patient data, and we highlight the ways in which these modalities of artificial intelligence might one day play a role in neurocritical care.

CONCLUSIONS

While none of these artificial intelligence systems are meant to replace the clinician's judgment, these systems have the potential to reduce healthcare costs and errors or delays in medical management.

Acute Management of Hypertension Following Intracerebral Hemorrhage

Intracerebral hemorrhage (ICH) is responsible for approximately 15% of strokes annually in the United States, with nearly 1 in 3 of these patients dying without ever leaving the hospital. Because this disproportionate mortality risk has been stagnant for nearly 3 decades, a main area of research has been focused on the optimal strategies to reduce mortality and improve functional outcomes. The acute hypertensive response following ICH has been shown to facilitate ICH expansion and is a strong predictor of mortality. Rapidly reducing blood pressure was once thought to induce cerebral ischemia, though has been found to be safe in certain patient populations. Clinicians must work quickly to determine whether specific patient populations may benefit from acute lowering of systolic blood pressure (SBP) following ICH. This review provides nurses with a summary of the available literature on blood pressure control following ICH. It focuses on intravenous and oral antihypertensive medications available in the United States that may be utilized to acutely lower SBP, as well as medications outside of the antihypertensive class used during the acute setting that may reduce SBP.

The role of psychosocial determinants in predicting adherence to treatment in patient with hypertension

INTRODUCTION

Non-adherence in patients with hypertension directly exacerbates clinical outcomes. The purpose of the present research is to study the recognition of the relationships between the perceived social support and self-efficacy and the satisfaction of health care agents and the interaction of the patient with therapeutic personnel and access to health care and the behaviors of adherence to treatment in the patients who suffer hypertension.

MATERIALS AND METHODS

This descriptive cross-sectional correlation study recruited 250 patients from a specialized hypertension clinic in Semnan, who completed the following questionnaires: Multidimensional Scale of Perceived Social Support, self-efficacy, adherence to treatment, access to and satisfaction with health care, and the patient's interaction with treatment personnel.

RESULTS

An overall statistical description of the sample consists of 89 (35.6%) men and 161 (64.4%) women (SD = 10.41, range = 51.98). Regression coefficient of previous variables (three steps) shows that self-efficacy share, consent form civil services, and job could demonstrate with 99% certainty in the changes of treatment conformity in a meaningful way.

CONCLUSIONS

High self-efficacy, satisfaction with health care, and a favorable job have a high direct effect on adherence to treatment in patients with hypertension and controlling hypertension. Social support and education do not have a significant impact on adherence to treatment.

Weaning failure of cardiovascular origin: how to suspect, detect and treat-a review of the literature

Among the multiple causes of weaning failure from mechanical ventilation, cardiovascular dysfunction is increasingly recognized as a quite frequent cause that can be treated successfully. In this review, we summarize the contemporary evidence of the most important clinical and diagnostic aspects of weaning failure of cardiovascular origin with special focus on treatment. Pathophysiological mechanisms are complex and mainly include increase in right and left ventricular preload and afterload and potentially induce myocardial ischemia. Patients at risk include those with preexisting cardiopulmonary disease either known or suspected. Clinically, cardiovascular etiology as a predominant cause or a contributor to weaning failure, though critical for early diagnosis and intervention, may be difficult to be recognized and distinguished from noncardiac causes suggesting the need of high suspicion. A cardiovascular diagnostic workup including bedside echocardiography, lung ultrasound, electrocardiogram and biomarkers of cardiovascular dysfunction or other adjunct techniques and, in selected cases, right heart catheterization and/or coronary angiography, should be obtained to confirm the diagnosis. Official clinical practice guidelines that address treatment of a confirmed weaning-induced cardiovascular dysfunction do not exist. As the etiologies of weaning-induced cardiovascular dysfunction are diverse, principles of management depend on the individual pathophysiological mechanisms, including preload optimization by fluid removal, guided by B-type natriuretic peptide measurement, nitrates administration in excessive afterload and/or myocardial ischemia, contractility improvement in severe systolic dysfunction as well as other rational treatment in specific indications in order to lead to successful weaning from mechanical ventilation.

Management of hypertensive crises in the elderly

Hypertensive crises are elevations of blood pressure higher than 180/120 mmHg. These can be urgent or emergent, depending on the presence of end organ damage. The clinical presentation of hypertensive crises is quite variable in elderly patients, and clinicians must be suspicious of non-specific symptoms. Managing hypertensive crises in elderly patients needs meticulous knowledge of the pathophysiological changes in them, pharmacological options, pharmacokinetics of the medications used, their side effects, and their interactions with other medications. Clevidipine, nicardipine, labetalol, esmolol, and fenoldopam are among the preferred choices in the elderly due to their efficacy and tolerability. Nitroprusside, hydralazine, and nifedipine should be avoided, unless there are no other options available, due to the high risk of complications and unpredictable responses.

Therapies to Reduce Blood Pressure Acutely

Clinicians make frequent treatment decisions regarding acute blood pressure reduction for the critically ill. Key to the decision making process is a balance between reducing arterial wall stress and maintaining perfusion to vital organs. In this article, we review the physiological considerations underlying acute blood pressure management, including the concept of cerebral autoregulation and its adaptations to chronic hypertension. We then discuss available pharmacological interventions suited for reducing blood pressure acutely. We also discuss specific blood pressure targets in common critical illnesses and consider future directions in this therapeutic area.

The role of brain natriuretic peptide in predicting renal outcome and fluid management in critically ill patients

BACKGROUND/PURPOSE

Fluid overload is associated with acute kidney injury (AKI) and mortality. There is no convenient precise method to guide fluid therapy in critically ill patients. We aimed to investigate whether brain natriuretic peptide (BNP) can predict the renal outcome and mortality of critically ill patients and be used to guide fluid management.

METHODS

This prospective observational study included patients who were admitted to the intensive care unit (ICU). Patients with underlying heart disease and heart dysfunction were excluded. Plasma BNP levels were obtained on admission (D0), at 24 hours (D1), and at 48 hours (D2). The primary outcome was AKI development during the ICU stay and recovery of AKI at ICU discharge. The secondary outcome was in-ICU mortality.

RESULTS

One hundred and sixty-three patients were enrolled for analysis. The delta-BNP level within the initial 24 hours after ICU admission rather than fluid accumulation was significantly correlated with delta-central venous pressure levels (r = 0.219, p = 0.010). Delta-Brain natriuretic peptide levels of < 81.8% within the initial 24 hours was an independent predictor of better renal outcome (i.e., no AKI or AKI with recovery). The increment in the BNP level from D0 to D1 was also a significant risk factor of mortality. In the a priori subgroup analysis for patients with sepsis, delta-BNP levels from D0 to D1 remained a significant predictor of renal outcome and mortality.

CONCLUSION

Our study showed that delta-BNP levels within 24 hours of admission to the ICU are better than fluid accumulation as a predictor of AKI, recovery, and mortality.