Peripheral Edema, Central Venous Pressure, and Risk of AKI in Critical Illness

Abstract

Background and objectives Although venous congestion has been linked to renal dysfunction in heart failure, its significance in a broader context has not been investigated.Design, setting, participants, & measurements Using an inception cohort of 12,778 critically ill adult patients admitted to an urban tertiary medical center between 2001 and 2008, we examined whether the presence of peripheral edema on admission physical examination was associated with an increased risk of AKI within the first 7 days of critical illness. In addition, in those with admission central venous pressure (CVP) measurements, we examined the association of CVPs with subsequent AKI. AKI was defined using the Kidney Disease Improving Global Outcomes criteria.Results Of the 18% (n=2338) of patients with peripheral edema on admission, 27% (n=631) developed AKI, compared with 16% (n=1713) of those without peripheral edema. In a model that included adjustment for comorbidities, severity of illness, and the presence of pulmonary edema, peripheral edema was associated with a 30% higher risk of AKI (95% confidence interval [95% CI], 1.15 to 1.46; P,0.001), whereas pulmonary edema was not significantly related to risk. Peripheral edema was also associated with a 13% higher adjusted risk of a higher AKI stage (95% CI, 1.07 to 1.20; P,0.001). Furthermore, levels of trace, 1+, 2+, and 3+ edema were associated with 34% (95% CI, 1.10 to 1.65), 17% (95% CI, 0.96 to 1.14), 47% (95% CI, 1.18 to 1.83), and 57% (95% CI, 1.07 to 2.31) higher adjusted risk of AKI, respectively, compared with edema-free patients. In the 4761 patients with admission CVP measurements, each 1 cm H 2 O higher CVP was associated with a 2% higher adjusted risk of AKI (95% CI, 1.00 to 1.03; P=0.02).Conclusions Venous congestion, as manifested as either peripheral edema or increased CVP, is directly associated with AKI in critically ill patients. Whether treatment of venous congestion with diuretics can modify this risk will require further study.

Cardiac and Vascular Surgery–Associated Acute Kidney Injury: The 20th International Consensus Conference of the ADQI (Acute Disease Quality Initiative) Group

“…The role of venous congestion in the development of AKI is a potential area of pathophysiological significance . The role of high central venous pressure in congestive heart failure is well appreciated .…”

“…26 The role of venous congestion in the development of AKI is a potential area of pathophysiological significance. 28,29 The role of high central venous pressure in congestive heart failure is well appreciated. 30 The incidence of AKI in this population has led investigators to study it in the context of heart surgery, for which the problem is typically in the right heart, and vascular surgery, for which the problem may be increased abdominal compartment pressures.…”

Proton Pump Inhibitors Are Not Associated With Acute Kidney Injury in Critical Illness

“…Demographic information included age, sex, and ethnicity, coded as white, African‐American, Asian, Hispanic, other, or unknown, and ICU type (medical, surgical, or cardiac). We used oral diabetes medication or insulin usage as identified in admission medication lists, along with Elixhauser discharge coding, to identify diabetic patients . We identified heart failure patients through NLP searching of the past medical history section of the admission examination or Elixhauser discharge coding.…”

Possible applications of normative lower to upper limb ratios of tissue dielectric constant to lower extremity edema

“…Peripheral edema has also been reported to be predictive of acute renal injury in a manner dependent on the level of assessed edema using edema grades 1-3. 14 The clinical assessment of peripheral edema is largely tactile and visual. A significantly puffy and swollen limb with a smoothing of skin architecture and absence of visualized surface veins is a visual part fairly descriptive of edema presence.…”