High Mortality After Total Knee Arthroplasty Periprosthetic Joint Infection is Related to Preoperative Morbidity and the Disease Process but Not Treatment.

BACKGROUND: Periprosthetic joint infection (PJI) mortality rate is approximately 20%. The etiology for high mortality remains unknown. The objective of this study was to determine whether mortality was associated with preoperative morbidity (frailty), sequalae of treatment, or the PJI disease process itself. METHODS: A multicenter observational study was completed comparing 184 patients treated with septic revision total knee arthroplasty (TKA) to a control group of 38 patients treated with aseptic revision TKA. Primary outcomes included time and the cause of death. Secondary outcomes included preoperative comorbidities and Charlson Comorbidity Index (CCMI) measured preoperatively and at various postoperative timepoints. RESULTS: The septic revision TKA cohort experienced earlier mortality compared to the aseptic cohort, with a higher mortality rate at 90 days, 1, 2, and 3 years after index revision surgery (P = .01). There was no significant difference for any single cause of death (P > .05 for each). The mean preoperative CCMI was higher (P = .005) in the septic revision TKA cohort. Both septic and aseptic cohorts experienced a significant increase in CCMI from the preoperative to 3 years postoperative (P < .0001 and P = .002) and time of death (P < .0001 both) timepoints. The septic revision TKA cohort had a higher CCMI 3 years postoperatively (P = .001) and at time of death (P = .046), but not one year postoperatively (P = .119). CONCLUSION: Compared to mortality from aseptic revision surgery, septic revision TKA is associated with earlier mortality, but there is no single specific etiology. As quantified by changes in CCMI, PJI mortality was associated with both frailty and the PJI disease process, but not treatment.

Outcomes of reoperative aortic root surgery.

OBJECTIVE: The study objective was to determine the impact of reoperative aortic root replacement on short-term outcomes and survival. METHODS: This was a retrospective study of aortic root operations from 2010 to 2018. All patients with a complete aortic root replacement were included, and patients undergoing valve-sparing root replacements were excluded. Patients were dichotomized by first-time sternotomy versus redo sternotomy, which was defined as having had a prior sternotomy for whatever reason. Within the redo sternotomy group, reoperative aortic root replacements were identified, being defined as a complete aortic root replacement in patients with a prior aortic root replacement; 1:1 nearest neighbor propensity matching was used to compare outcomes across groups. Kaplan-Meier survival estimates were generated and compared using log-rank statistics. RESULTS: A total of 893 patients undergoing complete ARR were identified, of whom 595 (67%) underwent first-time sternotomy and 298 (33%) underwent redo sternotomy. After matching, postoperative outcomes were similar for the first-time and redo sternotomy groups, including operative mortality. Redo sternotomy was not associated with reduced survival after aortic root replacement compared with first-time sternotomy (P = .084), with 5-year survival of 73.7% for first-time sternotomy and 72.9% for redo sternotomy. In the redo sternotomy group (n = 298), 69 (23%) were reoperative aortic root replacements and 229 (77%) were first-time aortic root replacements. After matching, postoperative outcomes were similar for the first-time and reoperative aortic root replacement groups, including operative mortality. Reoperative aortic root replacement was not associated with reduced survival, compared with first-time aortic root replacement (P = .870), with 5-year survival of 67.9% for first-time aortic root replacement and 72.1% for reoperative aortic root replacement. CONCLUSIONS: Reoperative aortic root replacement can be performed safely and provides similar survival to first-time aortic root replacement.

Handheld PET Probe for Pediatric Cancer Surgery.

18F-fluorodeoxyglucose (FDG) is a glucose analog that acts as a marker for glucose uptake and metabolism. FDG PET scans are used in monitoring pediatric cancers. The handheld PET probe localization of FDG-avid lesions is an emerging modality for radio-guided surgery (RGS). We sought to assess the utility of PET probe in localizing occult FDG-avid tumors in pediatric patients. PET probe functionality was evaluated by using a PET/CT scan calibration phantom. The PET probe was able to detect FDG photon emission from simulated tumors with an expected decay of the radioisotope over time. Specificity for simulated tumor detection was lower in a model that included background FDG. In a clinical model, eight pediatric patients with FDG-avid primary, recurrent or metastatic cancer underwent a tumor excision, utilizing IV FDG and PET probe survey. Adequate tissue for diagnosis was present in 16 of 17 resected specimens, and pathology was positive for malignancy in 12 of the 17 FDG-avid lesions. PET probe gamma counts per second were higher in tumors compared with adjacent benign tissue in all operations. The median ex vivo tumor-to-background ratio (TBR) was 4.0 (range 0.9-12). The PET probe confirmed the excision of occult FDG-avid tumors in eight pediatric patients.