Jim Koukounaras

Predictors of Outcome for Blunt High Grade Renal Injury Treated With Conservative Intent

PURPOSEnManagement for blunt high grade renal injury is controversial with most disagreement concerning indications for exploration. At our institution all patients are considered candidates for conservative treatment regardless of injury grade or computerized tomography appearance with clinical status the sole determinant for intervention. We define clinical factors predicting the need for emergency intervention as well the development of complications.nnnMATERIALS AND METHODSnWe analyzed the records of 117 patients with high grade renal injury (III to V) secondary to blunt trauma who presented to our institution in an 8-year period. Patients were categorized by the need for emergency intervention and, in those treated conservatively, by complications. We generated logistic regression models to identify significant clinical predictors of each outcome.nnnRESULTSnGrade III to V injury occurred in 48 (41.1%), 42 (35.9%) and 27 patients (23%), respectively. Of the 117 patients 20 (17.1%) required emergency intervention. On multivariate analysis only grade V injury (RR 4.4, 95% CI 1.9-10.5, p = 0.001) and the need for platelet transfusion (RR 8.9, 95% CI 2.1-32.1, p < 0.001) significantly predicted the need for intervention. A total of 90 patients (82.9%) who did not require emergency intervention underwent a trial of conservative treatment, of whom 9 (9.3%) experienced complications requiring procedural intervention. On multivariate analysis only patient age (RR 1.06, 95% CI 1.02-1.1, p = 0.004) and hypotension (RR 12, 95% CI 1.9-76.7, p = 0.009) were significant predictors.nnnCONCLUSIONSnHigh grade injury can be successfully managed conservatively. However, grade V injury and the need for platelet transfusion predict the need for emergency intervention while older patient age and hypotension predict complications.

A 9-year experience of renal injury at an Australian level 1 trauma centre

To detail the 9‐year experience of renal trauma at a modern Level 1 trauma centre and report on patterns of injury, management and complications.

Assessing the Usefulness of Delayed Imaging in Routine Followup for Renal Trauma

PURPOSEnRenal trauma is often managed conservatively. Repeat imaging within 48 hours of injury is recommended but to our knowledge the value of further delayed imaging is unknown. We determined the usefulness of routine followup imaging beyond 48 hours in cases of conservatively managed renal trauma.nnnMATERIALS AND METHODSnOf 377 patients who presented to our institution with renal injury in the last 8 years we identified 138 who underwent a trial of conservative treatment and repeat imaging more than 48 hours after injury. Followup imaging was categorized as routine in 108 patients (group 1) and indicated in 30 (group 2), and assessed for complications and the need for subsequent intervention.nnnRESULTSnOf the patients 121 (76%) were male. Mean age was 36 years. All except 4 injuries were the result of blunt trauma, predominantly due to road traffic accidents. Injury was grade 1 to 5 in 26, 24, 44, 33 and 11 cases, respectively. We identified 108 patients with routine followup imaging (group 1) while 30 were re-imaged due to a clinical indication. The rate of progression was 0.93% in group 1 with only 1 complication requiring a management change. In contrast, 20% of group 2 patients had progression requiring a treatment change (p = 0.0004).nnnCONCLUSIONSnRoutine re-imaging in patients with renal trauma outside the initial 48-hour window in the absence of a clear clinical indication had little benefit and changed treatment in less than 1%.

Role of Interventional Radiology in the Management of Chylothorax: A Review of the Current Management of High Output Chylothorax

Chylothorax is an uncommon type of pleural effusion whose etiology may be classified as traumatic or nontraumatic. Low-output chylothoraces usually respond well to conservative management, whereas high-output chylothoraces are more likely to require surgical or interventional treatment. Conservative management focuses on alleviation of symptoms, replacement of fluid and nutrient losses, and reduction of chyle output to facilitate spontaneous healing. Surgical management can be technically difficult due to the high incidence of variant anatomy and the high-risk patient population. Percutaneous treatments have rapidly developed and evolved during the past 14xa0years to represent a minimally invasive treatment compared with the more invasive nature of surgery. Percutaneous therapies provide a range of treatment options despite difficult or variant anatomy, with a reported high success rate coupled with low morbidity and mortality. This article is a review of etiology, diagnosis, and treatment of chylothorax, with a focus on interventional management techniques.

Endovascular Proximal Forearm Arteriovenous Fistula for Hemodialysis Access: Results of the Prospective, Multicenter Novel Endovascular Access Trial (NEAT)

BACKGROUNDnHemodialysis arteriovenous fistulas (AVFs) are suboptimally used primarily due to problems with maturation, early thrombosis, and patient nonacceptance. An endovascular approach to fistula creation without open surgery offers another hemodialysis vascular access option.nnnSTUDY DESIGNnProspective, single-arm, multicenter study (Novel Endovascular Access Trial [NEAT]).nnnSETTINGS & PARTICIPANTSnConsecutive adult non-dialysis-dependent and dialysis-dependent patients referred for vascular access creation at 9 centers in Canada, Australia, and New Zealand.nnnINTERVENTIONnUsing catheter-based endovascular technology and radiofrequency energy, an anastomosis was created between target vessels, resulting in an endovascular AVF (endoAVF).nnnOUTCOMESnSafety, efficacy, functional usability, and patency end points.nnnMEASUREMENTSnSafety as percentage of device-related serious adverse events; efficacy as percentage of endoAVFs physiologically suitable (brachial artery flowxa0≥ 500mL/min, vein diameterxa0≥ 4mm) for dialysis within 3 months; functional usability of endoAVFs to provide prescribed dialysis via 2-needle cannulation; primary and cumulative endoAVF patencies per standardized definitions.nnnRESULTSn80 patients were enrolled (20 roll-in and 60 participants in the full analysis set; the latter are reported). EndoAVFs were created in 98% of participants; 8% had a serious procedure-related adverse event (2%xa0device related). 87% were physiologically suitable for dialysis (eg, mean brachial artery flow, 918mL/min; endoAVF vein diameter, 5.2mm [cephalic vein]). EndoAVF functional usability was 64% in participants who received dialysis. 12-month primary and cumulative patencies were 69% and 84%, respectively.nnnLIMITATIONSnDue to the unique anatomy and vessels used to create endoAVFs, this was a single-arm study without a surgical comparator.nnnCONCLUSIONSnAn endoAVF can be reliably created using a radiofrequency magnetic catheter-based system, without open surgery and with minimal complications. The endoAVF can be successfully used for hemodialysis and demonstrated high 12-month cumulative patencies. It may be a viable alternative option for achieving AVFs for hemodialysis patients in need of vascular access.

Predicting surgical exploration in renal trauma: assessment and modification of an established nomogram.

BACKGROUND This study aimed to externally validate a previously described nomogram that predicts the need for renal exploration in the trauma setting. METHODS The predicted probability of nephrectomy was manually calculated using prospectively collected data from consecutive patients with renal trauma who presented to our institution between May 2001 and January 2010. To assess nomogram performance, receiver operating characteristic curves against the observed exploration rate were generated, and areas under the curve were calculated. Calibration curves were generated to assess performance across the range of predicted probabilities. Logistic regression modeling was used to determine clinical factors predicting exploration in a contemporary setting, and a nomogram was derived and internally validated using bootstrapping. RESULTS The established nomogram was applied to the 320 patients who presented during the 9-year period. The global performance of the established nomogram was very high, with an area under the curve of 0.95. However, the model performance was poor for higher predicted probabilities, thus lacking predictive ability in the population where the model has the greatest potential utility. A clinical tool was generated to better predict trauma nephrectomy in our contemporary population, using platelet transfusion within the first 24 hours, blood urea nitrogen, hemoglobin, and heart rate on admission. The global accuracy for the new model was similar to the previous nomogram, but it was significantly better calibrated for patients with higher probabilities of nephrectomy, with good predictive accuracy even in patients with Grade 5 injuries. CONCLUSION Older nomogram fails to accurately predict renal exploration in high-grade injuries in the contemporary setting. A new nomogram that more accurately predicts the need for exploration is presented. LEVEL OF EVIDENCE Therapeutic study, level IV; prognostic study, level III.

Radiological insertion of Tenckhoff catheters for peritoneal dialysis: a 1-year single-centre experience

Background Peritoneal dialysis (PD) is an important home-based dialysis modality for patients with end-stage kidney disease (ESKD). The initiation of PD requires timely and skilled insertion of a Tenckhoff catheter (TC). At most centres, TCs are inserted laparoscopically by surgeons under general anaesthetic. This requires access to increasingly scarce surgical, anaesthetic and hospital inpatient resources. Radiological insertion of TCs performed as a day procedure under local anaesthetic allows for easier access to the TC insertion with reduced resource requirements. We report our 1-year experience following the introduction of this technique to our PD programme. Methods This is a retrospective review of the outcomes for all patients who had TCs inserted radiologically (percutaneously with the assistance of ultrasound and fluoroscopy) over the 12-month period from December 2011 to December 2012. Relevant patient demographics collected included age, gender, body mass index (BMI), previous abdominal surgery and cause of ESKD. Extended details of the insertion procedure were also obtained including length of stay, early complications and time to first use of the catheter for PD. Results Thirty Argyle™ Swan Neck TCs were inserted under radiological guidance during the study period. The mean age of patients was 56 (SD ± 14). The male-to-female ratio was 2:1. The mean BMI was 25.7 (SD ± 4.8). PD was the initial dialysis modality in 22 (73%) patients. Of the 30 patients, 14 (46.7%) had previously undergone extraperitoneal abdominal surgery. All catheters were inserted successfully as day cases except four patients (13.3%) who had catheters inserted during an inpatient hospital admission. Most catheters were not accessed for a minimum of 10 days to reduce the chance of exit site leakage, in two cases the catheters were used within 5 days without complication. There were no cases of peritonitis or exit site infection during the observation period. Catheter migration occurred in four patients (13.3%) but only one required surgical intervention. Minor pain issues were noted in six patients (20%) and bleeding around the exit site requiring suturing in two patients (6.7%). The introduction of this technique at our institution saw a 67% increase in the number of patients performing PD. Conclusions Radiological insertion of TCs for PD provided improved access to catheter insertion in a timely manner with reduced resource requirements. Over the 12-month observation period we noted a high technical success rate with very few complications. Our study supports radiological insertion of TCs under local anaesthetic as a viable alternative to catheter insertion in theatre under general anaesthetic. The relative ease of radiological TC insertion has resulted in a significant increase in patient uptake of PD at our centre.

Prolonged balloon tamponade in the initial management of inferior vena cava injury following complicated filter retrieval, without the need for surgery

Advanced techniques have been described to remove embedded inferior vena cava (IVC) filters including the loop snare and modified loop snare (Hangman) techniques. Retrieval of embedded filters have been associated with higher rates of complications including IVC injury and stenosis. We report two challenging embedded retrievals complicated by IVC injury and haemorrhage. Haemostasis was successfully achieved with prolonged balloon tamponade, suggesting that injury to the IVC during filter retrieval may not need urgent surgery. However, both patients received short‐term complications related to caval thrombosis and patients in this cohort should be closely observed after retrieval. These cases support rigorous attention to filter indication and follow‐up.

Percutaneous insertion of peritoneal dialysis catheters using ultrasound and fluoroscopic guidance: A single centre experience and review of literature

Various methods of peritoneal dialysis (PD) catheter insertion are available. The purpose of this study was to evaluate a percutaneous insertion technique using ultrasound (US) and fluoroscopy performed under conscious sedation and as day case procedure. Data of 87 percutaneous inserted dialysis catheters were prospectively collected, including patients age, gender, body mass index, history of previous abdominal surgery and cause of end stage renal failure. Length of hospital stay, early complications and time to first use were also recorded. Institutional review board approval was obtained. A 100% technical success rate was observed. Early complications included bleeding (nu2009=u20093), catheter dysfunction (nu2009=u20096), exit site infection (nu2009=u20091) and exit site leakage (nu2009=u20091). All cases of catheter dysfunction and one case of bleeding required surgical revision. Median time of follow‐up was 18 months (range 3–35), and median time from insertion to first use was days 14 (1–47). Of the 82 patients who started dialysis, 20 (23%) ceased PD at some stage during follow‐up. Most frequently encountered reasons include deteriorating patient cognitive or functional status (nu2009=u20095), successful transplant kidney (nu2009=u20094) and pleuro‐peritoneal fistula (nu2009=u20094). Sixty‐two (71%) PD catheter insertions were performed as day case. The remaining insertions were performed on patients already admitted to the hospital. Percutaneous insertion of dialysis catheter using US and fluoroscopy is not only safe but can be performed as day case procedure in most patients, even with a medical history of abdominal surgery and/or obesity.

Irreversible Electroporation of Kidney Tumours

While there are numerous options for treatment of small (<4 cm) renal masses, irreversible electroporation (IRE) is a unique method of ablation which is reliable, safe and effective. Unlike other ablation methods, there is no need to cool the ureter or separate the colon from the kidney by injecting fluid into the perinephric space. Even when lesions extend into the central portion of the kidney, IRE is not associated with significant bleeding or haematuria. IRE is especially effective in the elderly or those with impaired renal function.