Echocardiography Does not Reduce Mortality in Sepsis: A Re-Evaluation Using the Medical Information Mart for Intensive Care IV Dataset

OBJECTIVES

Echocardiography is commonly used for hemodynamic assessment in sepsis, but data regarding its association with outcome are conflicting. The aim of this study was to evaluate the association between echocardiography and outcomes in patients with septic shock using the Medical Information Mart for Intensive Care IV database.

DESIGN

Retrospective cohort study comparing patients who did or did not undergo transthoracic echocardiography within the first 5 days of admission for the primary outcome of 28-day mortality.

SETTING

Admissions to the Beth Israel Deaconess Medical Center intensive care from 2008 to 2019.

PATIENTS

Adults 16 years old or older with septic shock requiring vasopressor support within 48 hours of admission. Readmissions and patients admitted to the coronary care unit or cardiovascular intensive care were excluded, as well as patients with ST-elevation myocardial infarction or cardiac arrest.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Echocardiography was performed in 1,515 (27%) of 5,697 eligible admissions. The primary outcome was analyzed using a marginal structural model and rolling entry matching to adjust for baseline and time-varying confounders. Patients who underwent echocardiography showed no significant difference in 28-day mortality (adjusted hazard ratio 1.09; 95% CI, 0.95-1.25; p = 0.24). This was consistent across multiple sensitivity analyses. Secondary outcomes were changes in management instituted within 4 hours of imaging. Treatment changes occurred in 493 patients (33%) compared with 431 matched controls (29%), with the most common intervention being the administration of a fluid bolus.

CONCLUSIONS

Echocardiography in sepsis was not associated with a reduction in 28-day mortality based on observational data. These findings do not negate the utility of echo in cases of diagnostic uncertainty or inadequate response to initial treatment.

What Is the Optimal Speed of correction of the Hyperosmolar Hyperglycemic State in Diabetic Ketoacidosis? An Observational Cohort Study of U.S. Intensive Care Patients

OBJECTIVE

The international guidelines for the treatment of diabetic ketoacidosis (DKA) advise against rapid changes in osmolarity and glucose; however, the optimal rates of correction are unknown. We aimed to evaluate the rates of change in tonicity and glucose level in intensive care patients with DKA and their relationship with mortality and altered mental status.

METHODS

This is an observational cohort study using 2 publicly available databases of U.S. intensive care patients (Medical Information Mart for Intensive Care-IV and Electronic Intensive Care Unit), evaluating adults with DKA and associated hyperosmolarity (baseline Osm ≥300 mOsm/L). The primary outcome was hospital mortality. The secondary neurologic outcome used a composite of diagnosed cerebral edema or Glasgow Coma Scale score of ≤12. Multivariable regression models were used to control for confounding factors.

RESULTS

On adjusted analysis, patients who underwent the most rapid correction of up to approximately 3 mmol/L/hour in tonicity had reduced mortality (n = 2307; odds ratio [OR], 0.21; overall P < .001) and adverse neurologic outcomes (OR, 0.44; P < .001). Faster correction of glucose levels up to 5 mmol/L/hour (90 mg/dL/hour) was associated with improvements in mortality (n = 2361; OR, 0.24; P = .020) and adverse neurologic events (OR, 0.52; P = .046). The number of patients corrected significantly faster than these rates was low. A maximal hourly rate of correction between 2 and 5 mmol/L for tonicity was associated with the lowest mortality rate on adjusted analysis.

CONCLUSION

Based on large-volume observational data, relatively rapid correction of tonicity and glucose level was associated with lower mortality and more favorable neurologic outcomes. Avoiding a maximum hourly rate of correction of tonicity >5 mmol/L may be advisable.

The importance of hyperosmolarity in diabetic ketoacidosis

AIM

Diabetic ketoacidosis is a hyperglycaemic emergency that is often treated in intensive care units (ICUs) despite having a low mortality and good prognosis. Current risk stratification is based primarily on acidosis, but it has been suggested that hyperosmolarity may also be an important marker of increased severity. Our aim was to evaluate the relationship between raised serum osmolarity and adverse clinical outcomes in ICU admissions for ketoacidosis.

METHODS

Retrospective review of prospectively collected data for adult admissions with ketoacidosis in the Australian and New Zealand Intensive Care Society Adult Patient Database over a 15-year period (2004-2018). Exclusions were readmissions and records with critical missing data. Serum hyperosmolarity was defined as > 320 mosm/l. The primary outcome was hospital mortality; secondary outcomes were ICU mortality and other adverse clinical events.

RESULTS

Some 17 379 admissions were included in the study population. People with hyperosmolarity had fourfold increased mortality, a higher incidence of renal failure and need for mechanical ventilation, and prolonged ICU and hospital length of stay. The relationship with mortality remained highly significant even after adjusting for severity of acidosis, hospital type, year of admission, time to ICU, and a modified Australia and New Zealand Risk of Death propensity score.

CONCLUSIONS

Although adults with ketoacidosis have a good prognosis overall, hyperosmolarity was independently associated with a significantly higher incidence of multiple adverse outcomes including mortality. Whether or not this is directly causal, it may have practical applications to improve risk stratification and identify individuals at risk of adverse outcomes.

An audit of perioperative blood transfusions in a regional hospital to rationalise a maximum surgical blood ordering schedule

Appropriate preoperative blood typing and cross-matching is an important quality improvement target to minimise costs and rationalise the use of blood bank resources. This can be facilitated using a maximum surgical blood ordering schedule (MSBOS) for specific operations. It is recommended that individual hospitals develop a site-specific MSBOS based on institutional data, but this is challenging in non-tertiary centres without electronic databases. Our aim was to audit our perioperative blood transfusions to develop a site-specific MSBOS. A retrospective audit of blood transfusions in surgical patients in our regional referral hospital was conducted using five years' coded administrative data. Procedures with higher transfusion rates warranting preoperative testing (type and screen with or without subsequent cross-matching) were identified. There were about 15,000 eligible surgical procedures performed in our institution over the audit period. The need for preoperative testing was identified for only a few procedures, namely laparotomy, bowel resection, major amputation, joint arthroplasty, hip/femur fracture and humerus surgery, and procedures for obstetric complications. We observed a reduction in transfusion rates over time for total joint arthroplasty. The use of coding data represents an efficient method by which centres without electronic anaesthesia information management systems can conduct large-scale audits to develop a site-specific MSBOS. This would represent a significant improvement for hospitals that currently base preoperative testing recommendations on expert opinion alone. As many procedures in regional centres have very low transfusion rates, hospitals with a similar case mix to ours could consider selectively auditing higher-risk operations where local data is most likely to alter testing recommendations.