Operative Versus Nonoperative Management of Hemorrhage in the Postoperative Kidney Transplant Patient.

BACKGROUND: Postoperative hemorrhage has been described at rates of 14% in kidney transplant (KT) literature. The preferred management of postoperative hemorrhage in this population is not well described. We hypothesized a difference in outcomes with operative versus nonoperative management of hemorrhage after kidney transplantation. METHODS: We conducted a retrospective cohort study of consecutive KTs from 2012 to 2019 (living and deceased donors). We defined hemorrhage based on the objective finding of hematoma on either ultrasound or CT scan. Management was defined as operative (surgical intervention with or without transfusion) or nonoperative (with or without transfusion). RESULTS: We performed 1758 KTs of which 135 (8%) demonstrated hematoma on ultrasound or CT scan (66 operative vs 69 nonoperative management). The clinical signs and symptoms of low urine output (P = .044), drop in hemoglobin (P < .001), abdominal pain (P = .005), and MAP < 70 mm Hg (P = .034) were 92.5% predictive of postoperative hemorrhage in our KT patients. There were no differences between groups based on medical history, preop anticoagulation, anastomosis type, cold ischemic time, lowest hemoglobin, delayed graft function, or complications. Patients with nonoperative treatment of postoperative hemorrhage had shorter lengths of stay (P = .003), better graft survival (P = .01), and better patient survival (P = .01). DISCUSSION: We found better outcomes of graft and patient survival with shorter lengths of stay when we utilized nonoperative management of postoperative hemorrhage in KT patients. Our findings suggest a role for conservative nonoperative management in select patients. Ultimately, it is the surgeon's choice on how best to manage postoperative hemorrhage.

Vagus nerve stimulation promotes generalization of conditioned fear extinction and reduces anxiety in rats.

BACKGROUND: Exposure-based therapies are used to treat a variety of trauma- and anxiety-related disorders by generating successful extinction following cue exposure during treatment. The development of adjuvant strategies that accelerate extinction learning, improve tolerability, and increase efficiency of treatment could increase the efficacy of exposure-based therapies. Vagus nerve stimulation (VNS) paired with exposure can enhance fear extinction, in rat models of psychiatric disorders, and chronic administration of VNS reduces anxiety in rats and humans. OBJECTIVE: We tested whether VNS, like other cognitive enhancers, could produce generalization of extinction for stimuli that are not presented during the extinction sessions, but are associated with the fear event. METHODS: Male Sprague Dawley rats underwent auditory fear conditioning with two easily discriminable auditory stimuli. Following fear conditioning, extinction training consisted of exposure to only one of the conditioned sounds. Half of the rats received VNS and half received sham stimulation during with sound presentations. VNS effects on anxiety were examined in a separate study where VNS was administered prior to testing on the elevated plus maze. RESULTS: Sham stimulated rats given 20 presentations of a conditioned stimulus (CS) during the extinction session showed performance that was matched to VNS-treated rats given only 4 presentations of the CS. Despite comparable levels of freezing to the presented CS, only the VNS-treated rats showed a significant decrease in freezing to the CS that was not presented. VNS-induced generalization of extinction was observed only when the two sounds were paired with footshock within the same fear conditioning session; VNS did not promote generalization of extinction when the two sounds were conditioned on different days or in different contexts. On the anxiety test, VNS administration significantly increased time spent in the open arms of the elevated plus maze. CONCLUSION: These results provide evidence that VNS can promote generalization of extinction to other stimuli associated with a specific fear experience. Furthermore, non-contingent VNS appears to reduce anxiety. The ability to generalize extinction and reduce anxiety makes VNS a potential candidate for use as an adjunctive strategy to improve the efficacy and tolerability of exposure-based therapies.