Impact of a Quality Assessment Program on Radiologist Performance in Ultrasound-Guided Renal Transplant Biopsy

The impact of blood pressure on the risk of major bleeding complication after renal transplant biopsy

PURPOSE

To assess the impact of elevated blood pressure on the rate of major hemorrhagic complication after renal transplant biopsy.

METHODS

Pre-procedural systolic (SBP), diastolic (SBP), and mean arterial (MAP) blood pressure for consecutive patients undergoing US-guided renal transplant biopsies from 08/01/2015 to 7/31/2017 were retrospectively recorded. Patients who had a major bleeding complication were identified. The risk of complication as a function of SBP, DBP, and MAP was statistically analyzed, with significance set at p < 0.05.

RESULTS

Of 1689 biopsies, there were 10 bleeding complications (10/1689, 0.59%). There was no statistically significant difference between biopsies with complication compared to those without complication based on SBP (p = 0.351), DBP (p = 0.088), or MAP (p = 0.132). Using risk dichotomization criteria, the odds ratio for hemorrhagic complication when the patient had SBP ≥ 180 mmHg and DBP ≥ 95 mmHg was 75.63 (95% CI 6.87-516.8, p = 0.002).

CONCLUSION

The rate of hemorrhagic complication from renal transplant biopsy is low, and there is no statistically significant threshold for increased biopsy risk based on SBP, DBP, or MAP alone. The risk of complication was significantly higher only when both the SBP is ≥ 180 mmHg and DBP is ≥ 95 mmHg.

Added Benefit and Risk of an Additional Biopsy or Targeting With Contrast-Enhanced Ultrasound for Patients With Renal Transplants

OBJECTIVES

To determine whether renal transplant diagnoses substantially change when 2 biopsy sites are chosen and whether contrast-enhanced ultrasound (CEUS) has value for targeting the second site.

METHODS

We prospectively enrolled 40 patients undergoing ultrasound-guided renal transplant biopsy within 2 years of transplant: 20, surveillance; and 20, for cause. A CEUS examination was performed to identify cortical regions with subjectively altered flow. One biopsy was performed at the operator-preferred (primary) site regardless of CEUS findings. Another biopsy was done at a second location, either targeted to an area in which CEUS perfusion findings differed from the primary site (targeted) or at a random location (secondary) if no other area differed. Specimens were randomly labeled A or B; pathologists were blinded to the CEUS result and biopsy location. Location-specific CEUS assessments were recorded. Pathologic results were compared, including acute and chronic Banff scores and any new findings from the targeted or secondary biopsy.

RESULTS

Forty patients were enrolled between January 2016 and December 2018. No location-specific pathologic differences correlated with differences in CEUS assessments. The second biopsy provided additional information that changed management in 4 of 40 patients (10.0% [95% confidence interval, 2.8%-23.7%]). Major bleeding complications occurred in 3 of 40 (7.5%) patients.

CONCLUSIONS

Contrast-enhanced ultrasound targeting was not useful. Major bleeding complications were higher than expected, possibly due to the additional biopsy away from the operator-preferred location. Obtaining a second renal transplant biopsy from a substantially different area than the initial operator-preferred location provided additional clinically useful information in 10% of patients.

Detection of Bleeding Complications After Renal Transplant Biopsy

OBJECTIVE. The purpose of this study was to analyze the timing of major bleeding complications after renal transplant biopsy in the context of a standardized 1-hour postprocedure observation protocol. MATERIALS AND METHODS. We retrospectively reviewed the electronic medical records for consecutive patients who underwent ultrasound-guided renal transplant biopsies between January 1, 2012, and December 31, 2017, and were observed according to a newly implemented 1-hour postprocedure observation protocol. The development of a major bleeding complication (Common Terminology Criteria for Adverse Events class 3 or higher) was recorded along with all available details regarding the time course of patient symptoms and presentation. Complications were grouped into one of four categories according to onset time after biopsy: 2 hours or less (timing category 1), more than 2 hours but 4 hours or less (timing category 2), more than 4 hours but 8 hours or less (timing category 3), and more than 8 hours (timing category 4). RESULTS. In 1824 patients (769 women, 1055 men) who underwent 4519 consecutive ultrasound-guided renal transplant biopsies during the study period, 11 class 3 complications were found (11/4519 [0.2%]). Four of the 11 patients (36.4%) had symptoms during the 1-hour observation period. Of these four patients, three (3/11 [27.3%]) had substantial symptoms related to major bleeding and were classified as timing category 1, and one (1/11 [9.1%]) had initially minor symptoms that increased in severity more than 2 hours but within 4 hours and was classified as timing category 2. Seven of the 11 patients (63.6%) did not have any symptoms at 1 hour of observation and were discharged; three (27.3%) were classified as timing category 3, and four (36.4%) were classified as category 4. CONCLUSION. Major bleeding complications following ultrasound-guided renal transplant biopsy are rare (0.2% of patients in this study). In our study, more than half were not clinically apparent within 4 hours of biopsy. A 1-hour postprocedure recovery period can be safely used after renal transplant biopsy.

Diagnostic efficacy and safety of ultrasound-guided kidney transplant biopsy using cortex-only view: a retrospective single-center study

PURPOSE

Cortical biopsy is the cornerstone to reveal a cause of unexplained dysfunction of the kidney transplant. Nevertheless, only a few studies have reported the biopsy technique with its performance. We described a novel technique of ultrasound (US)-guided kidney transplant biopsy using cortex-only view and analyzed its diagnostic efficacy and safety.

MATERIALS AND METHODS

Between January 2014 and December 2016, a consecutive series of 188 patients who underwent US-guided kidney transplant biopsy using cortex-only view by an experienced radiologist were evaluated (mean age, 46.1 ± 12.5 years; range, 21-79 years). Biopsy time, biopsy distance, biopsy core number, and glomerular number per patient were recorded. Successful biopsy (e.g., adequate, 10 or more glomeruli; marginal, 7-9 glomeruli) and complication rates were investigated, using Banff criteria and Clavien-Dindo classification, respectively.

RESULTS

Mean biopsy time, distance, and core number were 20.6 ± 6.7 min (range, 10-44 min), 3.2 ± 0.7 cm (range, 2.1-5.4 cm), and 1.9 ± 0.3 (range, 1.0-3.0), respectively. Mean glomerular number per patient was 20.4 ± 10.0 (range, 0-54). Adequate and marginal biopsy rates were 87.2% (164/188) and 95.2% (179/188), respectively. There was no major complication requiring treatment (no patient with Clavien-Dindo grade 2 or greater complication), while there were self-limiting minor complications in 5 patients (overall complication rate, 2.7%).

CONCLUSION

US-guided biopsy using cortex-only view is feasible and safe in sampling cortical tissues of kidney transplant.

KEY POINTS

• Ultrasound (US)-guided kidney transplant biopsy using cortex-only view is feasible and safe. • Adequate and marginal biopsy rates were 87.2% and 95.2%, respectively. • No major complication requiring treatment occurred after biopsy.

Ultrasound-guided renal transplant biopsy: practical and pragmatic considerations

Sonographically guided percutaneous core biopsy of renal allografts has been performed for decades, providing valuable information in monitoring the status of normally functioning renal transplants as well as investigating the cause of renal transplant dysfunction. This article reviews practical aspects of biopsy technique using the cortical tangential approach, with consideration of factors that may influence biopsy success, including selection of biopsy device. Clinically important complications from renal transplant biopsy are uncommon; the most recent experience for one institution is analyzed in the context of existing evidence regarding the frequency and timing of these major complications, to understand pragmatic implications for peri-procedural care.

Use of Iterative Cycles in Quality Improvement Projects in Imaging: A Systematic Review

PURPOSE

Studies suggest that quality improvement (QI) projects in health care lack scientific rigor, but the actual frequency of use of proven scientific QI methodology is unknown. The purposes of this study are to (1) conduct a systematic review of QI projects in radiology journals on the frequency of use of iterative cycles, a marker of proven QI methodology, and (2) assess association of the use of iterative cycles with characteristics of these projects.

MATERIALS AND METHODS

We searched English-language radiology journals on MEDLINE between 2008 and 2015 for published QI studies. Three reviewers appraised studies and extracted data. Use of iterative cycles was identified, and results were summarized qualitatively. χ² Analysis evaluated associations of iterative cycles with other data elements.

RESULTS

Of 3,134 potentially eligible citations, 44 studies met inclusion criteria. Only 46% of these used iterative cycles to refine intervention. Use of iterative cycles were associated with projects designed to improve process, QI expert support, reporting of unintended effect of intervention, and explicitly stated use of iterative cycles. General lack of scientific rigor was represented by failure to report baseline data (9%), describe unintended effects (66%), and discuss limitations (36%).

CONCLUSIONS

Our systematic review found fewer than half of the QI projects in radiology journals used iterative cycles to refine intervention, a scientific strategy central to many proven improvement methodologies. Use of iterative approach was associated with projects designed to improve processes, QI expert support, report of unintended effect, and explicitly stated use of iterative cycles.

The Critically Ill Kidney Transplant Recipient: A Narrative Review

Kidney transplantation is the most common solid organ transplantation performed worldwide. Up to 6% of kidney transplant recipients experience a life-threatening complication that requires ICU admission, chiefly in the late posttransplantation period (≥ 6 months). Acute respiratory failure and septic shock are the main reasons for ICU admission. Cardiac pulmonary edema, bacterial pneumonia, acute graft pyelonephritis, and bloodstream infections account for the vast majority of diagnoses in the ICU. Pneumocystis jirovecii pneumonia is the most common opportunistic infection, and one-half of the patients so infected require mechanical ventilation. The incidence of cytomegalovirus visceral infections in the era of preemptive therapy has dramatically decreased. Drug-related neutropenia, sirolimus-related pneumonitis, and posterior reversible encephalopathy syndrome are among the most common immunosuppression-associated toxic effects. Importantly, the impact of critical illness on graft function is worrisome. Throughout the ICU stay, acute kidney injury is common, and about 40% of the recipients require renal replacement therapy. One-half of the patients are discharged alive and free from dialysis. Hospital mortality can reach 30% and correlates with acute illness severity and reason for ICU admission. Transplant characteristics are not predictors of short-term survival. Graft survival depends on pre-ICU graft function, disease severity, and renal toxicity of ICU investigations and treatments.