Arrhythmias in the ICU: what do we know?

Clinical Characteristics and Outcomes of Neurosurgical Patients at a Level III Intensive Care Unit in Pakistan: A Retrospective Cohort Study

Objective Neurosurgical patients account for the majority of cases across all surgical specialties that are admitted to the surgical intensive care unit (ICU) at our institution. The goal of this study was to analyze factors leading to ICU admission, type of neurosurgical intervention, length of ICU/hospital stays, and outcomes in terms of complications and ICU and in-hospital mortality. Methods This retrospective study conducted at the surgical ICU, Aga Khan University Hospital, investigated clinical data of neurosurgical patients admitted between January 2020 and June 2022. Quantitative data were collected regarding patients' characteristics, such as age, gender, comorbidities, type of surgical intervention, mode of surgery, source of admission to ICU, and type of osmotherapy. The primary and secondary outcomes were in terms of ICU and hospital mortality and complications. Results Among 321 patients admitted to the SICU, 197 were included according to inclusion/exclusion criteria. A total of 168 patients (85.3%) required surgical intervention, of whom 101 (60%) underwent elective surgery and 67 (40%) required emergency surgery. Thirteen patients died during the ICU or hospital stay, representing a mortality rate of 6.6%. The average length of stay in the ICU had a median IQR of 4 (4,6) days while the average hospital stay median IQR was 11 (12,18) days. Tracheostomy was performed in 77 patients (39%), and the median IQR day for tracheostomy was 4 (3,5) days. APACHE-II (Acute Physiology and Chronic Health Evaluation) score, length of ICU, and length of hospital stay were significantly higher in the deceased patients with a p-value of 0.042, 0.019, and 0.043, respectively. Conclusion In conclusion, this study on neurosurgical patients from the surgical intensive care unit of a low-middle-income country provided valuable insights about factors and their influence on outcomes. The study implies that a high APACHE-II score is linked to poorer outcomes for neurosurgical patients in this particular setting. Undertaking a large multicenter prospective study is vital for tailoring interventions and improving patient care in regions with limited resources where healthcare challenges may be distinct.

Cardiovascular Outcomes in the Acute Phase of COVID-19

The cumulative number of cases in the current global coronavirus disease 19 (COVID-19) pandemic, caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has exceeded 100 million, with the number of deaths caused by the infection having exceeded 2.5 million. Recent reports from most frontline researchers have revealed that SARS-CoV-2 can also cause fatal non-respiratory conditions, such as fatal cardiovascular events. One of the important mechanisms underlying the multiple organ damage that is now known to occur during the acute phase of SARS-CoV-2 infection is impairment of vascular function associated with inhibition of angiotensin-converting enzyme 2. To manage the risk of vascular dysfunction-related complications in patients with COVID-19, it would be pivotal to clearly elucidate the precise mechanisms by which SARS-CoV-2 infects endothelial cells to cause vascular dysfunction. In this review, we summarize the current state of knowledge about the mechanisms involved in the development of vascular dysfunction in the acute phase of COVID-19.

Risk of thromboembolism in patients developing critical illness-associated atrial fibrillation

Although common, the long-term significance of -developing atrial fibrillation (AF) during a period of critical illness is unclear. We undertook a retrospective cohort analysis to -assess the rate of thromboembolism (TE) in patients -developing atrial fibrillation de novo during admission to our intensive care unit. In total, 1,955 patients were followed up (-maximum follow-up 1,276 days) for the occurrence of TE, of which 220 (11.3%) had developed AF or atrial flutter during their critical care admission. There were 11 TE events among the patients with new AF (0.053 events per patient-year), compared with 18 in the non-AF group (0.0059 events per patient-year). The unadjusted hazard ratio for TE in patients developing new AF compared with those not developing AF was 8.09 (95% CI 3.08-17.19, p<0.001). In patients admitted to critical care, the development of AF appears to be associated with a significantly increased risk of subsequent thromboembolism.

Predictors of de novo atrial fibrillation in a non-cardiac intensive care unit

OBJECTIVE

To assess the predictors of de novo atrial fibrillation in patients in a non-cardiac intensive care unit.

METHODS

A total of 418 hospitalized patients were analyzed between January and September 2016 in a non-cardiac intensive care unit. Clinical characteristics, interventions, and biochemical markers were recorded during hospitalization. In-hospital mortality and length of hospital stay in the intensive care unit were also evaluated.

RESULTS

A total of 310 patients were included. The mean age of the patients was 61.0 ± 18.3 years, 49.4% were male, and 23.5% presented de novo atrial fibrillation. The multivariate model identified previous stroke (OR = 10.09; p = 0.016) and elevated levels of pro-B type natriuretic peptide (proBNP, OR = 1.28 for each 1,000pg/mL increment; p = 0.004) as independent predictors of de novo atrial fibrillation. Analysis of the proBNP receiver operating characteristic curve for prediction of de novo atrial fibrillation revealed an area under the curve of 0.816 (p < 0.001), with a sensitivity of 65.2% and a specificity of 82% for proBNP > 5,666pg/mL. There were no differences in mortality (p = 0.370), but the lengths of hospital stay (p = 0.002) and stay in the intensive care unit (p = 0.031) were higher in patients with de novo atrial fibrillation.

CONCLUSIONS

A history of previous stroke and elevated proBNP during hospitalization were independent predictors of de novo atrial fibrillation in the polyvalent intensive care unit. The proBNP is a useful and easy- and quick-access tool in the stratification of atrial fibrillation risk.

Risk factors and clinical outcomes of arrhythmias in the medical intensive care unit

BACKGROUND

The clinical impact of arrhythmias on the continuum of critical illness is unclear, and data in medical intensive care units (ICU) is lacking. In this study, we distinguish between different types of arrhythmias and evaluate if their distinction is of clinical importance based on ICU length of stay and mortality outcomes.

METHODS

We performed a retrospective analysis of 215 patients in a community-based teaching hospital medical ICU. Variables gathered include sociodemographic data, arrhythmias identified and interpreted by the study team, and admission diagnoses coded into clinical mediator categories based on theorized common risk pathways. Univariable and multivariable Poisson regression models were used to identify risk factors for developing arrhythmias by type, prolonged length of stay, and hospital mortality.

RESULTS

Significant arrhythmia was detected in 28.8 % of subjects with most new arrhythmia events developing within the first 3 days of ICU stay. Acute myocardial ischemia and acute kidney injury at the time of ICU admission were associated with an increased risk of developing supraventricular arrhythmias (SVA) (RR = 2.02; 95 % CI 1.08-3.78 and RR = 1.93; 95 %CI 1.09-3.37, respectively). SVA in the first 3 days of ICU stay was associated with an increased risk of prolonged ICU stay (RR = 1.47; 95 % CI 1.09-1.97). After controlling for clinical mediators, development of SVA was not independently associated with in-hospital mortality. No mediators significantly increased the risk of developing ventricular arrhythmias (VA). VA were not associated to prolonged ICU stay but were associated with increased risk of hospital mortality (RR = 1.93; 95 % CI 1.18-3.15).

CONCLUSIONS

It is important to distinguish between supraventricular and ventricular arrhythmias for outcomes in the medical ICU setting. Developing a new VA increases the risk of in-hospital mortality independently. Developing a new SVA increases the risk of having a prolonged ICU stay but does not appear to increase in-hospital mortality independently. These findings suggest that the development of a VA should be considered an independent morbid event and not necessarily the end result of a complicated clinical course, while a new SVA may be considered a cardiac complication of the disease continuum which may add complexity to an ICU stay.

[Atrial fibrillation in the ICU. Distinct entity--special treatment?]

Atrial fibrillation (AF) is the single most frequent arrhythmia in the intensive care unit, occurring among 44-61 % of all patients with arrhythmias in the intensive care unit. The success rate of electrical cardioversion (DC-CV) early after surgery is as low as 10-35 % in postoperative AF but 6 weeks after discharge 90 % are in sinus rhythm (SR). Several guidelines recommend rate control in these patients and rate control with β-blockers and calcium channel blockers is not inferior with respect to outcome, 6 min walk test, and quality of life. DC-CV is recommended in unstable and heart failure patients. The term resistant AF is suggested for that distinct situation of AF not amenable to cardioversion solely in the acute phase of critical illness.