Lowering Cranioplasty Infection Incidence with Novel Bone Flap Storage Protocol: A Retrospective Cohort Study.

BACKGROUND: After craniectomy, autologous bone flaps may be stored using wet or dry cryopreservation. After brain edema subsides, they are replaced during an operation termed cranioplasty. Cranioplasty is associated with 15% infection incidence. METHODS: We conducted a retrospective comparison of infection outcomes between wet and dry cryopreservation of cranioplasty bone flaps. Historically, bone flaps were stored utilizing wet cryopreservation-bone flap storage in 1 L of lactated Ringer's solution containing 80 mg gentamicin and 2 g nafcillin in a sterile plastic container secured in an unsterile plastic bag. Our newer dry cryopreservation protocol involved storage in gauze soaked in 80 mg gentamicin and 2 g nafcillin within a 3-layer sterile bag system. RESULTS: A total of 119 autologous bone flaps were included, with median follow-up of 3.9 months from cranioplasty. Overall, 10.9% became infected, requiring subsequent surgery; 18.4% of 49 bone flaps stored using wet cryopreservation became infected compared with only 5.7% of 70 dry cryopreservation bone flaps (P = 0.038; relative risk [RR] 0.311; absolute risk reduction 12.7%). Tobacco use (P = 0.076; RR 3.17) was not associated with increased infection risk. Infection incidence was similar for traumatic craniectomy indications compared to the other indications (12.0% trauma vs. 10.1% other; P = 0.750). On average, infected cranioplasty patients spent 8.5 more days hospitalized and faced increased risk of additional complications. CONCLUSIONS: Dry cryopreservation significantly decreases infection after cranioplasty when compared with wet cryopreservation, and this mitigates additional morbidity, mortality, and costs attributable to cranioplasty infection. Other nonmodifiable risk factors for cranioplasty infection were identified.

Management and outcomes of surgical site tuberculosis infection due to infected bone graft in spine surgery: a single-institution experience and 1-year postoperative follow-up.

OBJECTIVE: In 2021, several patients across the United States received bone allograft contaminated with Mycobacterium tuberculosis (TB). TB is typically a pulmonary infection with many possible extrapulmonary manifestations, including skeletal tuberculosis. However, TB is a rare causative organism of postoperative surgical site infection. Iatrogenic skeletal TB infections are not widely reported in the medical literature; therefore, treatment and associated outcomes are relatively unknown. In this series, the authors report 6 cases of patients who received a mesenchymal stem cell-enhanced bone graft infected with TB at their institution, including the clinical courses, imaging findings, management plans, and outcomes at 1 year postoperatively. METHODS: A retrospective review was performed of 6 consecutive patients who underwent spinal fusion surgery at the authors' institution and received bone graft from a lot contaminated with TB. Collected data included patient demographic characteristics, indications for surgery, surgical procedures performed, timing of contamination discovery, medical treatment, and follow-up information including reoperation, healing progress, and imaging findings. RESULTS: Five of 6 patients (83.3%) eventually tested positive for TB via interferon-gamma release assay or wound culture. They experienced significant complications, including surgical site infections with neck swelling, pain, dysphagia, and wound dehiscence. Extensive soft-tissue infection was common; however, significant bony involvement was not observed. Surgical wound debridement was required in 4 patients, and all patients received medical management with standard RIPE (rifampin, isoniazid pyrazinamide, pyridoxine, and ethambutol) therapy for 8 weeks with extension of rifampin and isoniazid for scheduled 12 months. All patients (excluding 1 patient who died of COVID-19) showed signs of improvement with adequately healing wounds at the most recent follow-up at a median (range) of 12 (6-13) months postoperatively. To date, no patients have developed pulmonary TB. CONCLUSIONS: Direct inoculation with TB via contaminated bone grafts resulted in a high rate of severe soft-tissue infection, although extensive skeletal and pulmonary involvement has not been observed at 1 year postoperatively; this review includes the longest reported follow-up period for this TB outbreak. Medical management remains the mainstay of therapy for these patients, with most patients showing recovery with oral antibiotic therapy. The severity of these infections arising from mesenchymal stem cell-containing bone allografts that undergo an alternative sterilization process than standard allografts raises concerns regarding the added risks of infection, which should be weighed against the expected benefits of these grafts.

Utility of neuromuscular blockade reversal in the evaluation of acute neurosurgical patients: A retrospective case-series.

OBJECTIVE: Sugammadex reversal of neuromuscular blocking agents (NMBAs) is usually performed postoperatively. A scarcity of literature exists exploring sugammadex use for timely neurological examination of neurosurgical patients. NMBAs, like rocuronium, are used in the Emergency Department during intubation and their unpredictable duration of action often impedes timely and accurate assessment of patient neurological status. We aim to explore the role of sugammadex in evaluating patients in need of acute neurosurgical care. METHODS: Retrospective assessment of patients presenting with traumatic brain injury or intracranial hemorrhage was conducted at our level 1 trauma center. Patients of interest were those for whom sugammadex reversal of rocuronium neuromuscular blockade, from intubating doses, was pursued to ensure timely neurologic assessment. Nine patients were identified for whom GCS pre-/post-sugammadex, rocuronium dosing, elapsed time between rocuronium administration and reversal, and clinical course data were retrieved. RESULTS: Arrival GCS was 5.2 ± 3.2, with intubation accomplished within 10 ± 2.5 min of presentation. Rocuronium dosing was consistent between patients, average single dose of 1.2 ± 0.3 mg/kg. Lingering neuromuscular blockade ranged from 28 to 132 min (87.3 ± 34.3 min). All patients exhibited a GCS of 3 T upon initial neurosurgical evaluation, prior to reversal. Post-reversal GCS rose to 6.0 T ± 2.2. Sugammadex facilitated more accurate clinical decision making in 8 of 9 patients, including prevention of unnecessary invasive procedures. Two of 9 patients were eventually discharged home or to a rehabilitation facility. CONCLUSIONS: Rocuronium neuromuscular blockade can linger beyond pharmacokinetic predictions, thus delaying timely and precise neurologic assessment. Our data suggests sugammadex may be a useful addition to the clinician's armamentarium for acute neurologic assessment in the neurosurgical population. Sugammadex may impact clinical decision-making in certain patients and allow for more informed decision-making by families and physicians alike. Prospective studies are needed to definitively assess the impact of sugammadex on outcomes in acute neurosurgical settings.

Efficacy and Safety of Subfascial Epidural Drainage Protocol After Intraoperative Durotomy in Posterior Thoracic and Lumbar Spine Surgery: Reoperation Prevention and Outcomes Among Drained and Undrained Cohorts.

BACKGROUND: Persistent cerebrospinal fluid (CSF) egress after durotomy in posterior thoracic or lumbar spine surgery may cause devastating complications. Persistent CSF leaks may require reoperation, which confers additional cost and morbidity. OBJECTIVE: To evaluate the efficacy of our subfascial epidural drainage protocol in the setting of durotomy to prevent reoperation. METHODS: A retrospective cohort study of drained and undrained cohorts was completed to identify factors associated with reoperation for persistent CSF leak-related symptoms. The efficacy and safety of this 7-day subfascial epidural drainage protocol was assessed by comparing reoperation incidence, perioperative complications, rehabilitation necessity, and readmissions. RESULTS: In total, 156 patients underwent subfascial epidural drainage, and 14 were not drained. Subfascial drainage for up to 7 days was associated with a significantly lower incidence of reoperation than no drainage (3.3% vs 14%, respectively; P = .03). Perioperative complication incidence was similar between cohorts (12.8% vs 21.4%, respectively; P = .37), and length of stay was unchanged regardless of drainage (median 7 days). Subfascial drainage conferred a nearly 2-fold relative risk reduction in inpatient rehabilitation requirement (RR 0.55) and 3-fold relative risk reduction in 30-day (RR 0.31) and 90-day readmission (RR 0.36). Factors associated with reoperation among drained patients included drainage longer than 7 days, tobacco use, age younger than 50 years, and longer segment operations. Revision spine surgery was associated with reoperation among undrained patients. CONCLUSION: When followed after durotomy, our subfascial epidural drainage protocol results in fewer reoperations than in an undrained cohort without prohibitive cost and no added morbidity.

Viscoelastic Testing and Coagulopathy of Traumatic Brain Injury.

A unique coagulopathy often manifests following traumatic brain injury, leading the clinician down a difficult decision path on appropriate prophylaxis and therapy. Conventional coagulation assays-such as prothrombin time, partial thromboplastin time, and international normalized ratio-have historically been utilized to assess hemostasis and guide treatment following traumatic brain injury. However, these plasma-based assays alone often lack the sensitivity to diagnose and adequately treat coagulopathy associated with traumatic brain injury. Here, we review the whole blood coagulation assays termed viscoelastic tests and their use in traumatic brain injury. Modified viscoelastic tests with platelet function assays have helped elucidate the underlying pathophysiology and guide clinical decisions in a goal-directed fashion. Platelet dysfunction appears to underlie most coagulopathies in this patient population, particularly at the adenosine diphosphate and/or arachidonic acid receptors. Future research will focus not only on the utility of viscoelastic tests in diagnosing coagulopathy in traumatic brain injury, but also on better defining the use of these tests as evidence-based and/or precision-based tools to improve patient outcomes.

Primary spinal melanoma: illustrative case.

BACKGROUND: Primary spinal melanoma is extremely rare, accounting for ∼1% of all primary melanomas. Typically presenting insidiously in the thoracic spinal cord, primary spinal melanomas can have an acute presentation due to their propensity to hemorrhage. OBSERVATIONS: Despite its rarity, primary spinal melanoma should be included in the differential diagnosis when a hemorrhagic pattern of T1 and T2 intensities is seen on magnetic resonance imaging. Furthermore, the complete diagnosis is crucial because the prognosis of a primary spinal melanoma is considerably more favorable than that of a primary cutaneous melanoma with metastatic spread. LESSONS: Resection is the treatment of choice, with some authors advocating for postoperative chemotherapy, immunotherapy, and/or radiation. We describe a case of acute quadriplegia from hemorrhagic primary spinal melanoma requiring resection.

Minimally invasive resection of an extrapelvic sciatic schwannoma.

Schwannomas associated with the sciatic nerve are relatively rare. Surgical excision of symptomatic sciatic schwannomas traditionally involves a posterior sciatic nerve approach with a large, open exposure and transection of the gluteal muscles. The authors provide a technical report of a minimally invasive approach for the resection of an extrapelvic schwannoma arising from the sciatic nerve. The patient was discharged to home on the same day of surgery and his symptoms of severe sciatica immediately and dramatically improved.

The antiproliferative effects of PPARgamma ligands in normal human mammary epithelial cells.

Peroxisome proliferator-activated receptor gamma (PPARgamma) is a transcription factor in the steroid nuclear receptor superfamily. Ligand activation of PPARgamma is associated with differentiation and an inhibition of proliferation in normal and malignant cells, including adipocytes, monocytes, and tumor cells in colon, prostate, and breast cancers. The current studies were undertaken to assess both the expression and functional activity of PPARgamma in cultured normal human mammary epithelial cells (HMECs) and tissue samples. Analyses by northern hybridization, immunoblotting, and immunohistochemistry demonstrate PPARgamma gene expression in HMECs and breast tissue specimens. DNA binding and transactivation assays indicate the presence of functionally active PPARgamma in HMECs. Treatment with PPARgamma selective ligands, 15-deoxy-delta-(12,14)-prostaglandin J2 (15dPGJ2) and ciglitazone, inhibits the growth of HMECs in a dose-dependent manner. This growth inhibition is associated with alterations in cell cycle progression and the induction of apoptosis.