Association between a prolonged corrected QT interval and outcomes in patients in a medical Intensive Care Unit

Introduction:

Patients admitted into a medical Intensive Care Unit (ICU) have varying illnesses and risk factors. An electrocardiogram (ECG) is a useful tool to assess the cardiac status. The aim of the study was to determine the prevalence of QT prolongation of the ECG in patients admitted to a medical ICU in a tertiary hospital, to assess outcomes in terms of mortality, cardiovascular events, and duration of ICU stay.

Materials and Methods:

Prospective observational study, 6 months duration, assessing the prevalence of prolonged corrected QT interval (QTc) at admission into a medical ICU. A QTc calculated by Bazett''s formula, of >440 ms for males and >460 ms for females was considered prolonged. Details of illness, clinical and lab parameters were monitored.

Results:

The total number of patients screened was 182. There was a high prevalence of prolonged QTc (30%) on admission to the ICU. This reduced to 19% on day 3 (P = 0.011). In patients with a prolonged QTc the odds ratio of adverse outcome from ICU was 3.17 (confidence interval [CI]: 1.52–6.63) (P = 0.001) and of adverse outcome for hospital stay was 2.27 (CI: 1.11–4.66) (P = 0.014). In the study, 35% of all patients received drugs with QT prolonging action. Of patients with a prolonged QTc at admission 18 (35%) received a QT prolonging drug.

Conclusions:

We found that prolonged QTc is common (30%) in our medical ICU at admission and a large proportion (35%) received drugs capable of prolonging QT interval. These patients with QTc prolongation have a higher odds ratio for adverse outcomes.     

Patient‐level Factors and the Quality of Care Delivered in Pediatric Emergency Departments

Objective

Quality of care delivered to adult patients in the emergency department (ED) is often associated with demographic and clinical factors such as a patient's race/ethnicity and insurance status. We sought to determine whether the quality of care delivered to children in the ED was associated with a variety of patient‐level factors.

Methods

This was a retrospective, observational cohort study. Pediatric patients (<18 years) who received care between January 2011 and December 2011 at one of 12 EDs participating in the Pediatric Emergency Care Applied Research Network (PECARN) were included. We analyzed demographic factors (including age, sex, and payment source) and clinical factors (including triage, chief complaint, and severity of illness). We measured quality of care using a previously validated implicit review instrument using chart review with a summary score that ranged from 5 to 35. We examined associations between demographic and clinical factors and quality of care using a hierarchical multivariable linear regression model with hospital site as a random effect.

Results

In the multivariable model, among the 620 ED encounters reviewed, we did not find any association between patient age, sex, race/ethnicity, and payment source and the quality of care delivered. However, we did find that some chief complaint categories were significantly associated with lower than average quality of care, including fever (–0.65 points in quality, 95% confidence interval [CI] = –1.24 to –0.06) and upper respiratory symptoms (–0.68 points in quality, 95% CI = –1.30 to –0.07).

Conclusion

We found that quality of ED care delivered to children among a cohort of 12 EDs participating in the PECARN was high and did not differ by patient age, sex, race/ethnicity, and payment source, but did vary by the presenting chief complaint.

     

Association with right atrial strain with right atrial pressure: an invasive validation study

Echocardiographic assessment of right atrial pressure (RAP) from inferior vena cava (RAP_IVC) dimension may underestimate catheter-derived (RAP_C). As right atrial (RA) deformation, measured by speckle tracking, is preload-dependent, we hypothesized that RA strain may improve estimation of RAP_C. Right atrial strain components [RA reservoir function (?R), peak RA contraction (?CT) and RA conduit function (?CD)] were measured in 125 of 175 patients who had echocardiography and invasive measures of RAP (median difference 1 day). To determine whether RA strain measures differentiated patients with correct vs incorrect RAP_IVC assessment, categories with RAP_IVC values?<?3, 8 and >?15 mmHg were compared with RAP_C groups?<?3, 4–7, 8–10, 11–14 and >?15 mmHg. Non-invasively determined RAP was significantly lower (p?=?0.001) than invasively determined RAP_C, with a weak correlation (r?=?0.35, p?<?0.001). RA strain components were associated with RA size, RV function and IVC size. In those with RAP_IVC?>?15 mmHg, half of patients were categorized into RAP?<?10 mmHg. There were no significant differences in RA characteristics that differentiated patients in whom echocardiographic estimation of RAP was inaccurate. Right atrial strain measures were feasible, and had associations with RA size, RV systolic function and IVC size. Right atrial strain was significantly different between those with normal vs raised pressure, but it did not identify those with incorrect echocardiographic assessment of RAP.