Acute Kidney Injury: Incidence, aetiology, management and outcome measures of a Samoan case series.

BACKGROUND: Acute Kidney Injury (AKI) is a major and under-recognised cause of morbidity and mortality worldwide. Low and middle-income countries bear the greatest burden of AKI (85%). There is currently no published literature on AKI from the Pacific Islands. The aim of the present study was to report the incidence, aetiology, management and outcomes measures of AKI from the tertiary referral hospital of Samoa. MATERIALS AND METHODS: Single-centre prospective observational study. Participants were recruited by the lead investigator from the hospital patient information system. The inclusion criteria for participation was (1) adults (>18 years) admitted to general wards of Tupua Tamasese Meaole (TTM) Hospital with a diagnosis of AKI between December 1, 2019 and May 31, 2020, and (2) serum creatinine level of >200 µmol/L, and (3) compliance with the current Kidney Disease Improving Global Outcomes (KDIGO) criteria for AKI diagnosis. The data collection form was adapted from the International Society for Nephrology - Global Snapshot Project, and recorded demographic and baseline characteristics, precipitating causes of AKI, treatment/management, and outcomes measures. RESULTS: There was a total of 114 AKI admissions over the study period corresponding to a hospital-based AKI incidence of 26.8 per 1000 admissions per 6 months. 75% of AKI cases were community acquired. The leading causes of AKI were dehydration (79%) and sepsis (64%). More than 40% of cases presented with two or more Non-Communicable Disease co-morbidities. The in-patient mortality rate was 20.2%. In the 3 months following discharge from hospital, 25% of AKI cases had completely resolved, 25% of patients had died, and 18.7% of AKI cases had progressed to chronic kidney disease. The leading causes of mortality were cardiovascular events (35%) and sepsis (35%). CONCLUSIONS: The hospital-based incidence and unfavourable outcomes of AKI are high in Samoa. Greater awareness of this under-recognised condition is warranted among the public, government officers, and health professionals.

First-week postoperative flow measurements are highly predictive of primary patency of radiocephalic arteriovenous fistulas.

PURPOSE: This study was conducted to determine whether volume flow rate at the first postoperative visit could predict early failure of radiocephalic arteriovenous fistulas (RCAVFs). METHODS: We retrospectively studied the records of 264 patients who received a RCAVF between 2007 and 2013 at our centers. Data collected included patient demographics, medical history, arterial and venous mapping, and volume flow rate intraoperatively after fistula creation but before closing the surgical incision. An intraoperative flow rate >100 mL/minute was targeted. We measured volume flow at the first postoperative visit 1 week after surgery and thereafter as needed. RESULTS: Intraoperative flow was not a significant predictor of primary patency (p = 0.44) but flow at the first postoperative visit was a statistically significant predictor of fistula primary patency (p = 0.002). No fistula with a blood flow <200 mL/minute at the 1-week postoperative visit reached maturity without receiving a maturation procedure. The hazard ratio for the first follow-up flow (mL/min) was 0.9973 (95% CI 0.9956, 0 .9989), indicating that for every 100 mL increase in blood flow the primary patency increases by 10%. CONCLUSIONS: Flow rate at the 1-week postoperative visit was the most important predictor of RCAVF patency. Thus, it should be possible to identify patients who would benefit from early intervention or closer follow-up as soon as the first postoperative visit. This should help reduce the use of bridging hemodialysis catheters and minimize the risks of catheter dependency.

A sterile elastic exsanguination tourniquet is effective in preventing blood loss during hemodialysis access surgery.

PURPOSE: We report the first use of a sterile elastic exsanguination tourniquet (SET) in performing hemodialysis vascular access procedures in 27 patients. The main advantages of this tourniquet are the reduction of blood loss and need for possible transfusions. Additional benefits are the near-perfect exsanguination and excellent exposure of the operative field. METHODS: This SET is a sterile elastic stockinet device that rolls up the arm starting from the hand by pulling on two handles. The elastic silicone ring provides sufficient pressure (220 ± 30 mmHg) to block arterial flow into the limb. The stockinet can be cut to provide access to the incision area while providing an additional sterile cover over the rest of the limb. RESULTS: No transfusions were required in any patients. Minor adverse effects occurred in four patients, including a twisted vessel, a bleeding vascular branch, a tear in atrophic arm skin, and pain, all of which had resolved on subsequent follow-up. Operational recommendations to avoid these adverse effects are outlined. CONCLUSIONS: We conclude that this sterile elastic exsanguination tourniquet is effective and safe in preventing bleeding during upper extremity hemodialysis vascular access procedures.

High incidence of perigraft seroma formation with gelatin-coated polytetrafluoroethylene grafts.

We reviewed the effectiveness of a gelatin-coated polytetrafluoroethylene (PTFE) graft designed to reduce suture line bleeding and graft weeping. Twenty-nine adults with end-stage renal disease underwent implantation the graft (n = 30) in the arm. All had preoperative ultrasound vascular mapping to assess their options for an autogenous arteriovenous fistula and patients with a history of prior central venous devices or sternotomy underwent contrast venography. A 4- to 7-mm tapered graft (n = 10) was used if the inflow artery was <4.0 mm in diameter, and a 6-mm straight graft (n = 20) was used if the artery was ≥4.0 mm. Intraoperative volume flows were measured by duplex methodology. Precautions to prevent ultrafiltration and seroma development were taken. Eleven clinically significant seromas were detected in 30 sealed PTFE grafts (36.7%), 10 in the 6-mm grafts (50%), and 1 in a 4- to 7-mm graft (10%), a significant difference between graft types. There were no significant differences in flow between the graft types and between grafts with seromas versus no seromas. Five grafts were explanted and one was ligated, resulting in cannulation delays from 2 to 4 months. We conclude that the gelatin-sealed PTFE vascular graft is not the ideal prosthesis for hemodialysis access.