Acute kidney injury after percutaneous nephrolithotomy for stones in solitary kidneys.

OBJECTIVES: The aim of this study was to report the incidence, severity, outcome and risk factors of acute kidney injury (AKI) following percutaneous nephrolithotomy (PNL) in solitary kidneys. METHODS: The study included consecutive adult patients who underwent PNL for treatment of calculi in a solitary kidney between May 2012 and July 2015. Patients with congenital renal anomalies or with stages 4 and 5 chronic kidney disease (CKD) were excluded. Serum creatinine levels were measured the day before PNL, daily after PNL for 2-5 days and after 3 months. AKI was depicted according to changes in early postoperative serum creatinine levels and its severity was determined based on the Acute Kidney Injury Network (AKIN) classification. The outcome of AKI was evaluated after 3 months by changes in the stage of CKD. Univariate and multivariate statistical analyses were conducted to determine risk factors for developing AKI. RESULTS: The study included 100 patients (62 males) with a mean ± SD age of 50 ± 11.7 years. Complications were reported for 27 patients. AKI developed in 25 patients; at the 3 month follow-up, 23 of them (92%) had completely recovered from AKI and two (8%) had developed stage 4 CKD. Independent risk factors for developing AKI were multiple PNL tracts and postoperative ureteric obstruction (relative risks were 14 and 22, respectively). CONCLUSIONS: The incidence of AKI was 25% after PNL for a solitary kidney. The likelihood of renal function recovery was 92%. Multiple PNL tracts and postoperative ureteric obstruction were risk factors for developing AKI.

The pharmacodynamics of vecuronium in chronic renal failure patients: the impact of different priming doses.

PURPOSE: The concept of priming was introduced to facilitate a faster onset of nondepolarizing neuromuscular blocker for endotracheal intubation. Vecuronium is still very much in use for most chronic renal failure patients posted for renal transplantation. The aim of this study was to examine the pharmacodynamics of vecuronium without and with preceding different small doses. METHODS: One hundred chronic renal failure patients were assigned into four groups according to the used vecuronium priming regimen. The first control group (V(0)-group), where no priming dose was given. The other three priming groups (V(10)- , V(15)- , and V(20)-groups), where 10%, 15%, and 20% of ED(95) of vecuronium were administrated 5 min prior to the remaining intubating dose (2 × ED(95)) of vecuronium. Neuromuscular blockade was measured via acceleromyographic response of the ulnar nerve. Train-of-four (TOF) ratio was measured every minute during priming interval. Any unpleasant symptoms during precurarization were recorded. Lag time and onset time (from injection of intubating dose) were recorded. Endotracheal intubation condition was scored blindly. The duration and recovery times were also recorded. RESULTS: The significant higher incidence of symptoms of paresis was encountered in V(20)-group in comparison with other two priming groups. TOF ratio started to decrease significantly at the first minute in V(20)-group, at the second minute in V(15)-group, and at the third minute in V(10)-group, till the fourth minute in the priming interval. Although TOF ratio was still above 0.90 in V(10)-group, it was below 0.80 in V(20)-group. Priming groups did not show significant intergroup difference in onset time. However, duration and recovery times were significantly longer in priming groups in comparison with V(0)-group without priming. CONCLUSION: Priming the chronic renal failure patients with 10% of ED(95) vecuronium dose acquit the best pharmacodynamics with the fewest signs of muscle weakness. Larger vecuronium priming doses are unfavorable and convey no more clinical utility.

The impact of timing of maximal crystalloid hydration on early graft function during kidney transplantation.

BACKGROUND: Early graft function is crucial for successful kidney transplantation. Maintaining adequate hydration is complicated by rapid movement of water to the extravascular space. We designed this study to test the effect of maximal hydration during graft ischemia time on early renal function. METHODS: Forty adult patients with chronic renal failure underwent renal transplantation from related living donors. Study subjects were randomly assigned 1 of 2 regimens for intraoperative hydration. The constant infusion rate group received normal saline 0.9% at an infusion rate 10 to 12 mL . kg(-1) . h(-1) from the start of surgery until the renal vessels were unclamped after vascular anastomosis. The central venous pressure target (CVPT) group received normal saline 0.9% titrated to maintain a specific central venous pressure (CVP). The target CVP from the start of surgery until clamping of the donor renal vessels was 5 mm Hg except for the interval from clamping of the renal vessels until the end of renal vascular anastomosis, when the target CVP was 15 mm Hg. Perioperative hemodynamics, infused saline volumes, rate of infusion, onset of diuresis, graft turgidity, urine volume, and renal function during the first 5 postoperative days were recorded. RESULTS: At the end of renal ischemia time, both groups had received approximately 3 L crystalloid solution. The CVPT group achieved the highest peak of intravascular volume expansion with an average infusion rate of 48.3 mL . min(-1) during 48 +/- 12 minutes of renal ischemia. The CVPT group had better graft function, required fewer vasopressors and diuretics, and had less postoperative tissue edema than the constant infusion rate group. CONCLUSIONS: Hydration directed toward maintaining a given CVP during kidney transplantation produced a more stable hemodynamic profile and promoted diuresis. The calculated infusion rate of approximately 45 to 50 mL . min(-1), within an hour ischemia time, seems feasible to enhance early graft function. A larger trial with long-term follow-up of renal function is warranted to confirm the clinical benefit of titrating IV crystalloid administration to maintain a given CVP in this population.

Robotic laparoscopic radical cystectomy inhalational versus total intravenous anesthesia: a pilot study.

BACKGROUND: Robotic assistance may refine laparoscopic radical cystectomy. Steep Trendelenburg tilt (TT) and pneumoperitoneum (PP) are challenging anesthesia maneuvers. In view of those maneuvers, would inhalational anesthesia or total intravenous anesthesia (TIVA) be the more appropriate anesthetic management for this kind of surgery? This issue is under consideration in this clinical trial. METHODS: 15 patients scheduled for robotic laparoscopic radical cystectomy (RLRC) were randomly allocated into two groups to be anesthetized by either isoflurane anesthesia (ISO n = 8) or ketamine-midazolam-fentanyl total intravenous anesthesia (TIVA n = 7). The hemo-respiratory dynamics, oxygenation and biochemical variables were monitored taking into consideration the system organ function as primary outcomes, and operative conditions and recovery profile as secondary outcomes. RESULTS: The PP and TT increased the mean arterial and airway pressures and decreased lung compliance, and were associated with respiratory acidemia, while changes in heart rate remained within normal range. The duration of PP was shorter in TIVA patients but mean arterial pressure was higher than ISO group. ISO was associated with increased plasma concentrations ofprothrombin, fibrinogen and aspartate aminotransferase. CONCLUSIONS: Though the number of patients is small in this study (n = 15), it nevertheless brings to light the advantages of TIVA during the robotic laparoscopic radical cystectomy (RLRC), by shortening the duration of PP without an increase in prothrombin and fibrinogen concentrations. A lager number of clinical trial are needed to further clarify this issue.

Prevention of hypothermia in children under combined epidural and general anesthesia: a comparison between upper- and lower-body warming.

BACKGROUND: Children receiving combined epidural and general anesthesia may be at greater risk of hypothermia. Active warming should be undertaken to combat heat loss. With combined epidural and general anesthesia heat loss from the lower body may be greater than from the upper body because of shift of blood towards the vasodilated lower body. We assumed that application of the warming blanket to the lower body might provide better protection against hypothermia. To test this hypothesis, lower-body warming (LBW) was compared with upper-body warming (UBW) in a randomized comparative study. METHODS: Children subjected to open urologic surgery under combined epidural and general anesthesia were randomly allocated to either UBW n = 38 or LBW n = 35 using a forced-air warming blanket. Core and peripheral skin temperatures were monitored. Temperature gradients between forearm and fingertip during LBW and between leg and toe during UBW were calculated. The warmer was set at 32 degrees C, room temperature was around 22 degrees C and fluids were infused at ambient room temperature. RESULTS: The changes in core temperature were comparable and parallel in both groups. Core temperature decreased significantly in each group at 1 h after induction compared with basal values. Temperature gradients at forearm-fingertip and at leg-toe were also comparable in both groups. Recovery was uneventful and no patient shivered in the recovery room. CONCLUSIONS: Lower body warming is as effective as UBW in prevention of hypothermia in children subjected to combined epidural and general anesthesia.