Impact of Post-PCI FFR Stratified by Coronary Artery.

BACKGROUND: Low fractional flow reserve (FFR) after percutaneous coronary intervention (PCI) has been associated with adverse clinical outcomes. Hitherto, this assessment has been independent of the epicardial vessel interrogated. OBJECTIVES: This study sought to assess the predictive capacity of post-PCI FFR for target vessel failure (TVF) stratified by coronary artery. METHODS: We performed a systematic review and individual patient-level data meta-analysis of randomized clinical trials and observational studies with protocol-recommended post-PCI FFR assessment. The difference in post-PCI FFR between left anterior descending (LAD) and non-LAD arteries was assessed using a random-effect models meta-analysis of mean differences. TVF was defined as a composite of cardiac death, target vessel myocardial infarction, and clinically driven target vessel revascularization. RESULTS: Overall, 3,336 vessels (n = 2,760 patients) with post-PCI FFR measurements were included in 9 studies. The weighted mean post-PCI FFR was 0.89 (95% CI: 0.87-0.90) and differed significantly between coronary vessels (LAD = 0.86; 95% CI: 0.85 to 0.88 vs non-LAD = 0.93; 95% CI: 0.91-0.94; P < 0.001). Post-PCI FFR was an independent predictor of TVF, with its risk increasing by 52% for every reduction of 0.10 FFR units, and this was mainly driven by TVR. The predictive capacity for TVF was poor for LAD arteries (AUC: 0.52; 95% CI: 0.47-0.58) and moderate for non-LAD arteries (AUC: 0.66; 95% CI: 0.59-0.73; LAD vs non-LAD arteries, P = 0.005). CONCLUSIONS: The LAD is associated with a lower post-PCI FFR than non-LAD arteries, emphasizing the importance of interpreting post-PCI FFR on a vessel-specific basis. Although a higher post-PCI FFR was associated with improved prognosis, its predictive capacity for events differs between the LAD and non-LAD arteries, being poor in the LAD and moderate in the non-LAD vessels.

Gender Differences and Outcomes of Hypoattenuated Leaflet Thickening (HALT) Following Transcatheter Aortic Valve Replacement: A Meta-analysis of Randomized and Cohort Studies.

Subclinical leaflet thrombosis is characterized by hypoattenuated leaflet thickening (HALT) after transcatheter aortic valve replacement (TAVR) on computed tomography. However, given the low incidence of HALT after TAVR, the clinical significance of HALT is still being investigated. We sought to generate a more reliable estimate of the risk factors and adverse outcomes associated with HALT after TAVR by pooling data from randomized trials and cohort studies. PubMed/Medline database was systematically searched from inception until November 24, 2021, using the following terms: ("hypoattenuated leaflet thickening" and "transcatheter aortic valve replacement") and ("Subclinical leaflet thrombosis" and "transcatheter aortic valve replacement"). A random effects model meta-analysis was conducted using Mantel-Haenszel odds ratios (ORs) and the associated 95% confidence intervals (CIs), mean difference and the associated 95%. Ten studies with a total of 1462 patients were included, with follow-up ranging between 4 months and 3 years. HALT occurred in 14.4% of the patients undergoing TAVR. HALT was not associated with increased risk of stroke/TIA (OR 1.38; 95% CI [0.61-3.11]; I2=0%) or increased risk of all-cause mortality (OR 0.67; 95% CI [0.25-1.80]; I2=0). HALT was associated with a greater post-procedural mean aortic valve gradient (mean difference 2.31 mmHg; 95% CI [0.27, 4.35]; I2=71%). Interestingly, there was a trend of higher risk of HALT in men (OR 1.37; 95% CI [0.82-2.30]; I2=44%) while there was a trend towards lower risk of HALT in the presence of CKD (OR 0.76; 95% CI [0.49-1.19]; I2=0%); these trends did not reach statistical significance. This meta-analysis shows that the occurrence of HALT following TAVR is associated with a greater post-procedural mean aortic valve gradient but no excess risk of death or cerebrovascular events. The clinical significance of this higher post-procedural mean aortic valve gradient is uncertain and requires further investigations.

Trans-Stent FFR Gradient as a Modifiable Integrant in Predicting Long-Term Target Vessel Failure.

BACKGROUND: Fractional flow reserve (FFR) after percutaneous coronary intervention (PCI) is associated with long-term outcomes. Data relating FFR-based trans-stent gradient (TSG) after PCI to long-term outcomes are sparse. OBJECTIVES: The aim of this study was to test whether TSG is associated with adverse events at follow-up after PCI. METHODS: Data were gathered from a prospective registry evaluating 501 vessels in 416 patients with median follow-up period of 596 days. Primary endpoints were: 1) target vessel failure (TVF), including target vessel revascularization, and target vessel myocardial infarction after discharge; and 2) major adverse cardiac events (MACE) including TVF, target vessel revascularization, nontarget vessel MI, cardiac death. RESULTS: After PCI, median post-PCI FFR was 0.86 and median TSG was 0.04. TSG >0.04 was associated with increased rates of TVF (8.7% vs 2.9%; P = 0.014) and MACE (17.8% vs 9.2%; P = 0.02). Post-PCI FFR < 0.86 was associated with increased rates of TVF (6.1% vs 2.2%; P = 0.03) and MACE (16.5% vs 10%; P = 0.036). The vessel subgroup with high TSG and low FFR had significantly higher rates of TVF (10.2%; P = 0.02) and MACE (20.1%; P = 0.049) than vessels with: 1) high TSG and high FFR (TVF, 2.9%; MACE, 9.7%); 2) low TSG and low FFR (TVF, 3.8%; MACE, 11.3%); and 3) low TSG high FFR (TVF, 2.2%; MACE, 7.5%). In multivariate analysis, TSG was independently predictive of TVF. CONCLUSIONS: Higher TSG was an independent predictor of adverse events, particularly TVF, and identified a subgroup of patients at higher risk for poor outcomes. The combination of high TSG and low FFR showed significantly worse outcomes compared with an "ideal result" (high FFR and low TSG). These data support a recommendation to use TSG during FFR evaluation to determine the functional success of PCI.

Elective percutaneous coronary intervention performed during contrast-induced hypotension.

OBJECTIVES: To demonstrate the feasibility and safety of performing elective percutaneous coronary intervention (PCI) during contrast reaction producing severe hypotension. BACKGROUND: The development of profound hypotension due to a contrast reaction requires emergency treatment and usually signals procedure termination. METHODS AND RESULTS: We report successful completion of planned PCI with blood pressure support with vasopressors during contrast-induced hypotension in nine procedures in three patients with previously known contrast reaction causing hypotension. CONCLUSIONS: This case series provides support for the feasibility and safety of performing successful planned PCI under blood pressure support in patients with contrast reaction causing severe hypotension. A management approach for considering intervention in the setting of contrast-induced hypotension is provided.

Systematic review of the evaluation and management of coronary pseudoaneurysm after stent implantation.

Pseudoaneurysm (PSA) formation is a rare but well-known complication of coronary stenting. It develops after a procedural perforation disrupts the integrity of the vessel wall but is contained by a single wall layer, usually pericardium, extravascular thrombosis and later fibrosis. Medical literature of PSA consists primarily of case reports. A systematic review of pseudoaneurysm after coronary stenting was performed to summarize its presentation, diagnostic imaging modalities, natural history, and management approaches. Clinical presentations range from asymptomatic to hemodynamic collapse, size from small to "giant," and treatment approaches from surgical or percutaneous exclusion to "watchful waiting" and imaging surveillance. Based on current information, a management algorithm is provided recommending urgent to emergent exclusion for symptomatic PSA, elective exclusion for large and giant PSA, and "watchful waiting" and periodic imaging surveillance for small to moderate sized PSA.

National Trends and Outcomes in Dialysis-Requiring Acute Kidney Injury in Heart Failure: 2002-2013.

BACKGROUND: Dialysis-requiring acute kidney injury (D-AKI) is a serious complication in hospitalized heart failure (HF) patients. However, data on national trends are lacking after 2002. METHODS: We used the Nationwide Inpatient Sample (2002-2013) to identify HF hospitalizations with and without D-AKI. We analyzed trends in incidence, in-hospital mortality, length of stay (LoS), and cost. We calculated adjusted odds ratios (aORs) for predictors of D-AKI and for outcomes including in-hospital mortality and adverse discharge (discharge to skilled nursing facilities, nursing homes, etc). RESULTS: We identified 11,205,743 HF hospitalizations. Across 2002-2013, the incidence of D-AKI doubled from 0.51% to 1.09%. We found male sex, younger age, African-American and Hispanic race, and various comorbidities and procedures, such as sepsis and mechanical ventilation, to be independent predictors of D-AKI in HF hospitalizations. D-AKI was associated with higher odds of in-hospital mortality (aOR 2.49, 95% confidence interval [CI] 2.36-2.63; P < .01) and adverse discharge (aOR 2.04, 95% CI 1.95-2.13; P < .01). In-hospital mortality and attributable risk of mortality due to D-AKI decreased across 2002-2013. LoS and cost also decreased across this period. CONCLUSIONS: The incidence of D-AKI in HF hospitalizations doubled across 2002-2013. Despite declining in-hospital mortality, LoS, and cost, D-AKI was associated with worse outcomes.

National Landscape of Unplanned 30-Day Readmissions in Patients With Left Ventricular Assist Device Implantation.

The number of patients with advanced heart failure receiving left ventricular assist device (LVAD) implantation has increased dramatically over the last decade. There are limited data available about the nationwide trends of complications leading to readmissions after implantation of contemporary devices. Patients who underwent LVAD implantation from January 2013 to December 2013 were identified using International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) code 37.66 from the Healthcare Cost and Utilization Project's National Readmission Database. The top causes of unplanned 30-day readmission after LVAD implantation were determined. Survey logistic regression was used to analyze the significant predictors of readmission. In 2013, there were 2,235 patients with an LVAD implantation. Of them, 665 (29.7%) had at least 1 unplanned readmission within 30 days, out of which 289 (43.4%) occurred within 10 days after discharge. Implant complications (14.9%), congestive heart failure (11.7%), and gastrointestinal bleeding (8.4%) were the top 3 diagnoses for the first readmission and accounted for more than a third of all readmissions. Significant predictors of readmissions included a prolonged length of stay during the index admission, Medicare insurance, and discharge to short-term facility. In conclusion, despite increased experience with LVADs, unplanned readmissions within 30 days of implantation remain significantly high.

Nationwide Trends in Hospital Outcomes and Utilization After Lower Limb Revascularization in Patients on Hemodialysis.

OBJECTIVES: This study aimed to describe the temporal trends and outcomes of endovascular and surgical revascularization in a large, nationally representative sample of patients with end-stage renal disease on hemodialysis hospitalized for peripheral artery disease (PAD). BACKGROUND: PAD is prevalent among patients with end-stage renal disease on hemodialysis and is associated with significant morbidity and mortality. There is a paucity of information on trends in endovascular and surgical revascularization and post-procedure outcomes in this population. METHODS: We used the Nationwide Inpatient Sample (2002 to 2012) to identify hemodialysis patients undergoing endovascular or surgical procedures for PAD using diagnostic and procedural codes. We compared trends in amputation, post-procedure complications, mortality, length of stay, and costs between the 2 groups using trend tests and logistic regression. RESULTS: There were 77,049 endovascular and 29,556 surgical procedures for PAD in hemodialysis patients. Trend analysis showed that endovascular procedures increased by nearly 3-fold, whereas there was a reciprocal decrease in surgical revascularization. Post-procedure complication rates were relatively stable in persons undergoing endovascular procedures but nearly doubled in those undergoing surgery. Surgery was associated with 1.8 times adjusted odds (95% confidence interval: 1.60 to 2.02) for complications and 1.6 times the adjusted odds for amputations (95% confidence interval: 1.40 to 1.75) but had similar mortality (adjusted odds ratio: 1.05; 95% confidence interval: 0.85 to 1.29) compared with endovascular procedures. Length of stay for endovascular procedures remained stable, whereas a decrease was seen for surgical procedures. Overall costs increased marginally for both procedures. CONCLUSIONS: Rates of endovascular procedures have increased, whereas those of surgeries have decreased. Surgical revascularization is associated with higher odds of overall complications. Further prospective studies and clinical trials are required to analyze the relationship between the severity of PAD and the revascularization strategy chosen.

Clinical Decision-Making for the Hemodynamic "Gray Zone" (FFR 0.75-0.80) and Long-Term Outcomes.

BACKGROUND: Fractional flow reserve (FFR) value between 0.75 and 0.80 is considered the "gray zone" and outcomes data relative to treatment strategy (revascularization vs medical therapy alone [deferral]) are limited for this group. METHODS AND RESULTS: A total of 238 patients (64.3 ± 8.6 years; 97% male; 45% diabetic) with gray-zone FFR were followed for the primary endpoint of major adverse cardiovascular event (MACE), defined as a composite of death, myocardial infarction (MI), and target-vessel revascularization. Mean follow-up duration was 30 ± 17 months. Deferred patients (n = 48 [20%]) had a higher prevalence of smoking and chronic kidney disease compared with the percutaneous coronary intervention (PCI) group (n = 190 [80%]; P<.05). Patients who underwent PCI had significantly lower MACE compared with the deferred patients (16% vs 40%; log rank P<.01). While there was a trend toward a decrease in all-cause mortality (8% vs 19%; log rank P=.06), the composite of death or MI was significantly lower in the PCI group (9% vs 27%; P<.01). On multivariate Cox proportional hazards regression analysis, PCI was associated with lower MACE (hazard ratio, 0.5; 95% confidence interval, 0.27-0.95; P=.03). CONCLUSION: Revascularization for patients with gray-zone FFR was associated with a significantly reduced risk of MACE compared with medical therapy alone.

Clinical and angiographic predictors of persistently ischemic fractional flow reserve after percutaneous revascularization.

AIMS: Despite optimal angiographic results after percutaneous coronary intervention (PCI), some lesions may continue to produce ischemia under maximal hyperemia. We evaluated the factors associated with persistently ischemic fractional flow reserve (FFR) after angiographically successful PCI. METHODS AND RESULTS: A total of 574 consecutive patients with 664 lesions undergoing PCI who had FFR pre- and post-PCI were analyzed. Percutaneous coronary intervention led to effective ischemia reduction from pre-FFR (0.65±0.14) to post-FFR (0.87±0.08; ∆FFR 0.22±0.16, P<.001). There were 63 (9.5%) lesions with a persistently ischemic FFR of ≤0.80 despite optimal angiographic PCI results. Multivariate analysis revealed the presence of diffuse disease (odds ratio [OR] 3.54, 95% CI 1.80-6.94, P<.01), left anterior descending artery PCI (OR 8.35, 95% CI 3.82-18.27, P<.01), use of intravenous adenosine for inducing hyperemia (OR 3.95, 95% CI 2.0-7.84, P<.01), and pre-PCI FFR (OR 0.03, 95% CI 0.004-0.23, P<.01) as independent predictors of persistently ischemic FFR (≤0.80) after PCI. The predictive accuracy of this model was robust, with an area under the curve of 0.85 (95% CI 0.82-0.88). CONCLUSION: Multiple factors are associated with persistently ischemic FFR after angiographically optimal PCI. It is recommended that in lesions with the above-identified factors, FFR should be remeasured after PCI, and if abnormal, further measures should be undertaken for functional optimization.

National Trends and Impact of Acute Kidney Injury Requiring Hemodialysis in Hospitalizations With Atrial Fibrillation.

BACKGROUND: Atrial fibrillation (AF) is a common cause for hospitalization, but there are limited data regarding acute kidney injury requiring dialysis (AKI-D) in AF hospitalizations. We aimed to assess temporal trends and outcomes in AF hospitalizations complicated by AKI-D utilizing a nationally representative database. METHODS AND RESULTS: Utilizing the Nationwide Inpatient Sample, AF hospitalizations and AKI-D were identified using diagnostic and procedure codes. Trends were analyzed overall and within subgroups and utilized multivariable logistic regression to generate adjusted odds ratios (aOR) for predictors and outcomes including mortality and adverse discharge. Between 2003 and 2012, 3751 (0.11%) of 3 497 677 AF hospitalizations were complicated by AKI-D. The trend increased from 0.3/1000 hospitalizations in 2003 to 1.5/1000 hospitalizations in 2012, with higher increases in males and black patients. Temporal changes in demographics and comorbidities explained a substantial proportion but not the entire trend. Significant comorbidities associated with AKI-D included mechanical ventilation (aOR 13.12; 95% CI 9.88-17.43); sepsis (aOR 8.20; 95% CI 6.00-11.20); and liver failure (aOR 3.72; 95% CI 2.92-4.75). AKI-D was associated with higher risk of in-hospital mortality (aOR 3.54; 95% CI 2.81-4.47) and adverse discharge (aOR 4.01; 95% CI 3.12-5.17). Although percentage mortality within AKI-D decreased over the decade, attributable risk percentage mortality remained stable. CONCLUSIONS: AF hospitalizations complicated by AKI-D have quintupled over the last decade with differential increase by demographic groups. AKI-D is associated with significant morbidity and mortality. Without effective AKI-D therapies, focus should be on early risk stratification and prevention to avoid this devastating complication.

Clinical and prognostic value of poststenting fractional flow reserve in acute coronary syndromes.

OBJECTIVES: Fractional flow reserve (FFR) has been suggested to have value in acute coronary syndromes (ACSs). The clinical and prognostic value of ischaemia reduction assessed by post-percutaneous coronary intervention (PCI) FFR has not been studied in this population. METHODS: Consecutive stable ischaemic heart disease (SIHD) (N=390) and patients with ACS (N=189) who had pre-PCI FFR and post-PCI FFR were followed for 2.4±1.5 years. Primary endpoint was major adverse cardiac events (MACE) (composite of myocardial infarction, target vessel revascularisation and death). RESULTS: In patients with ACS, PCI led to significant improvement in FFR from 0.62±0.15 to post-PCI FFR 0.88±0.08 (p<0.0001). Post-PCI FFR identified 29 patients (15%) who had persistently low FFR<0.80 (0.75±0.06) despite angiographically optimal results prompting subsequent interventions improving repeat FFR (0.85±0.06; p<0.0001). The difference in MACE events between patients with ACS and patients with SIHD varied according to the post-PCI FFR value (interaction p=0.044). Receiver operator curve analysis identified a final FFR cut-off of ≤0.91 as having the best predictive accuracy for MACE in the ACS study population (30% vs 19%; p=0.03). Patients with ACS achieving final FFR of >0.91 had similar outcomes compared with patients who had SIHD (19% vs 16%; p=0.51). However, in patients with final FFR of ≤0.91 there was increased MACE versus patients with SIHD (30% vs 16%; p<0.01). CONCLUSIONS: Post-PCI FFR is valuable in assessing the functional outcome of PCI in patients with ACS. Use of post-PCI FFR in patients with ACS allows for functional optimisation of PCI results and is predictive of long-term outcomes in patients with ACS.

A Nationwide Analysis of Outcomes of Weekend Admissions for Intracerebral Hemorrhage Shows Disparities Based on Hospital Teaching Status.

BACKGROUND AND PURPOSE: With the "weekend effect" being well described, the Brain Attack Coalition released a set of "best practice" guidelines in 2005, with the goal to uniformly provide standard of care to patients with stroke. We attempted to define a "weekend effect" in outcomes among patients with intracranial hemorrhage (ICH) over the last decade, utilizing the Nationwide Inpatient Sample (NIS) data. We also attempted to analyze the trend of such an effect. MATERIALS AND METHODS: We determined the association of ICH weekend admissions with hospital outcomes including mortality, adverse discharge, length of stay, and cost compared to weekday admissions using multivariable logistic regression. We extracted our study cohort from the NIS, the largest all-payer data set in the United States. RESULTS: Of 485 329 ICH admissions from 2002 to 2011, 27.5% were weekend admissions. Overall, weekend admissions were associated with 11% higher odds of in-hospital mortality. When analyzed in 3-year groups, excess mortality of weekend admissions showed temporal decline. There was higher mortality with weekend admissions in nonteaching hospitals persisted (odds ratios 1.16, 1.13, and 1.09, respectively, for 3-year subgroups). Patients admitted during weekends were also 9% more likely to have an adverse discharge (odds ratio 1.09; 95% confidence interval: 1.07-1.11; P < .001) with no variation by hospital status. There was no effect of a weekend admission on either length of stay or cost of care. CONCLUSION: Nontraumatic ICH admissions on weekends have higher in-hospital mortality and adverse discharge. This demonstrates need for in-depth review for elucidating this discrepancy and stricter adherence to standard-of-care guidelines to ensure uniform care.

A National Perspective of Do-Not-Resuscitate Order Utilization Predictors in Intracerebral Hemorrhage.

Nontraumatic intracerebral hemorrhage (ICH) is associated with substantial morbidity and mortality. Do-not-resuscitate (DNR) orders are linked to poorer outcomes in patients with ICH, possibly due to less active management. Demographic, regional, and social factors, not related to ICH severity, have not been adequately looked at as significant predictors of DNR utilization. We reviewed the Healthcare Cost and Utilization Project's Nationwide Inpatient Sample (NIS) database in 2011 for adult ICH admissions and DNR status. We generated hierarchical 2-level multivariate regression models to estimate adjusted odds ratios. We analyzed 25 768 ICH hospitalizations, 18% of which (4620 hospitalizations) had DNR orders, corresponding to national estimates of 126 254 and 22 668, respectively. In multivariable regression, female gender, white or Hispanic/Latino ethnicity, no insurance coverage, and teaching hospitals were significantly associated with increased DNR utilization after adjusting for confounders. There was also significantly more interhospital variability in the lowest quartile of hospital volume. In conclusion, demographic factors and insurance status are significantly associated with increased DNR utilization, with more individual hospital variability in low-volume hospitals. The reasons for this are likely qualitative and linked to patient, provider, and hospital practices.

Incidence, Risk Factors, and Outcome Trends of Acute Kidney Injury in Elective Total Hip and Knee Arthroplasty.

Over the past decade, there has been a marked increase in the number of primary and revision total hip and knee arthroplasties performed in the United States. Acute kidney injury (AKI) is a common complication of these procedures; however, little is known about its epidemiology in the elective arthroplasty population. We conducted a study to determine the incidence, risk factors, and outcomes of AKI after elective joint arthroplasty. Drawing on the Nationwide Inpatient Sample database, we found that the proportion of hospitalizations complicated by AKI increased rapidly from 0.5% in 2002 to 1.8% to 1.9% in 2012. Multivariate analysis revealed that the key risk factors for AKI were chronic kidney disease and the postoperative events of sepsis, acute myocardial infarction, and blood transfusion. Moreover, codiagnosis with chronic kidney disease increased the risk for AKI associated with all 3 postoperative events. After adjusting for confounders, we found an association between AKI and a significantly increased risk for in-hospital mortality and discharge to long-term facilities. AKI serves as an important quality indicator in elective hip and knee surgeries. With elective arthroplasties expected to rise, carefully planned approach to interdisciplinary perioperative care is essential to reduce both the risk and consequences of AKI.

Dialysis Requiring Acute Kidney Injury in Acute Cerebrovascular Accident Hospitalizations.

BACKGROUND AND PURPOSE: The epidemiology of dialysis requiring acute kidney injury (AKI-D) in acute ischemic stroke (AIS) and intracerebral hemorrhage (ICH) admissions is poorly understood with previous studies being from a single center or year. METHODS: We used the Nationwide Inpatient Sample to evaluate the yearly incidence trends of AKI-D in hospitalizations with AIS and ICH from 2002 to 2011. We also evaluated the trend of impact of AKI-D on in-hospital mortality and adverse discharge using adjusted odds ratios (aOR) after adjusting for demographics and comorbidity indices. RESULTS: We extracted a total of 3,937,928 and 696,754 hospitalizations with AIS and ICH, respectively. AKI-D occurred in 1.5 and 3.5 per 1000 in AIS and ICH admissions, respectively. Incidence of admissions complicated by AKI-D doubled from 0.9/1000 to 1.7/1000 in AIS and from 2.1/1000 to 4.3/1000 in ICH admissions. In AIS admissions, AKI-D was associated with 30% higher odds of mortality (aOR, 1.30; 95% confidence interval, 1.12-1.48; P<0.001) and 18% higher odds of adverse discharge (aOR, 1.18; 95% confidence interval, 1.02-1.37; P<0.001). Similarly, in ICH admissions, AKI-D was associated with twice the odds of mortality (aOR, 1.95; 95% confidence interval, 1.61-2.36; P<0.01) and 74% higher odds of adverse discharge (aOR, 1.74; 95% confidence interval, 1.34-2.24; P<0.01). Attributable risk percent of mortality was high with AKI-D (98%-99%) and did not change significantly over the study period. CONCLUSIONS: Incidence of AKI-D complicating hospitalizations with cerebrovascular accident continues to grow and is associated with increased mortality and adverse discharge. This highlights the need for early diagnosis, better risk stratification, and preparedness for need for complex long-term care in this vulnerable population.

Systematic oral hydration with water is similar to parenteral hydration for prevention of contrast-induced nephropathy: an updated meta-analysis of randomised clinical data.

BACKGROUND: Contrast-induced nephropathy (CIN) is the third most common cause of hospital-acquired kidney injury and is related to increased long-term morbidity and mortality. Adequate intravenous (IV) hydration has been demonstrated to lessen its occurrence. Oral (PO) hydration with water is inexpensive and readily available but its role for CIN prevention is yet to be determined. METHODS: PubMed, EMBASE and the Cochrane Central register of controlled trials (CENTRAL) databases were searched until April 2015 and studies were selected using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist. All randomised clinical trials with head-to-head comparison between PO and IV hydration were included. RESULTS: A total of 5 studies with 477 patients were included in the analysis, 255 of those receiving PO water. The incidence of CIN was statistically similar in the IV and PO arms (7.7% and 8.2%, respectively; relative risk 0.97; 95% CI 0.36 to 2.94; p=0.95). The incidence of CIN was statistically similar in the IV and PO arms in patients with chronic kidney disease and with normal renal function. Rise in creatinine at 48-72 h was lower in the PO hydration group compared with IV hydration (pooled standard mean difference 0.04; 95% CI 0.03 to 0.06; p<0.001; I(2)=62%). CONCLUSIONS: Our meta-analysis shows that systematic PO hydration with water is at least as effective as IV hydration with saline to prevent CIN. PO hydration is cheaper and more easily administered than IV hydration, thus making it more attractive and just as effective.