Upper extremity neuromonitoring changes are more common than lower extremity during spinal fusion for Scheuermann's kyphosis.

INTRODUCTION: The purpose of this study is to determine the incidence of intraoperative neuromonitoring (IONM) changes and postoperative neurologic deficit in patients with Scheuermann's Kyphosis (SK) undergoing posterior spinal fusion (PSF). METHODS: Single-center, retrospective chart review of the clinical, surgical and IONM data (somatosensory evoked potential (SSEP) and neurogenic motor evoked potential (NMEP) or transcranial motor evoked potential (TcMEP)) from patients with SK undergoing PSF at our center from 1993 to 2021. RESULTS: One hundred and four SK patients (mean 16.4 ± 1.9 years) underwent PSF with correction of kyphosis from mean 79.4 ± 10.8° to 35.4 ± 13.9°. MEP data were obtained using either NMEP in 34.6% of patients) or TcMEP in 65.4% of patients. Only 3.8% of cases had lower extremity (LE) IONM changes during surgery, with no postoperative neurologic deficits in those patients. IONM changes occurred more frequently in the upper extremities (UE) with 14 (13.4%) patients having changes in UE SSEPs. Patients with UE IONM changes had significantly longer surgical times (p = 0.0096) and higher number of levels fused (p = 0.003) compared to patients without changes. Their weight, but not BMI, was also significantly higher (p = 0.036). These UE IONM changes resolved with arm repositioning in all but one patient who had a postoperative UE neurapraxia that resolved by 6 weeks. There was 1 postoperative transient femoral nerve palsy without IONM changes thought to be due to patient positioning. CONCLUSION: The incidence of critical LE IONM changes during PSF for SK is 3.4%, which is similar to that reported in AIS. UE IONM changes are significantly more common at 13.4%, revealing that these patients are vulnerable to malpositioning of the arms during surgery.

Incisional Negative Pressure Wound Therapy Does Not Affect Deep Surgical Site Infection Rates in Neuromuscular Scoliosis Surgery.

Surgical site infection (SSI) is a devastating complication in patients with neuromuscular scoliosis (NMS) undergoing posterior spinal instrumented fusion (PSIF) for progressive scoliosis. Incisional negative pressure wound therapy (INPWT) has been used in other surgical fields to reduce SSI. Our purpose was to examine the prophylactic use of INPWT after NMS surgery to decrease SSI. At a single institution, 71 consecutive patients with NMS underwent PSIF from 2015 to 2019. Starting in 2017, all patients with NMS received INPWT postoperatively until discharge. Rates of deep SSI were compared between the two cohorts of patients. Additionally, patient demographic and operative factors such as American Society of Anesthesiologists score, number of levels instrumented, need for an anterior spinal release, need for spinal fusion to pelvis, blood loss, operative time, fluoroscopy time, length of stay, and transfusion requirement were analyzed for potential influence on deep SSI. There was no significant difference in deep SSI rates between patients who received INPWT (2 of 41) and those treated with a standard postoperative dressing (2 of 30; P=1.0). Although INPWT theoretically can stabilize the wound environment and prevent deep SSI, our findings do not support this. More research is needed to evaluate the efficacy of INPWT after PSIF for NMS. [Orthopedics. 2023;46(6):373-378.].

Time-of-day specific changes in metabolic detoxification and insecticide resistance in the malaria mosquito Anopheles gambiae.

Mosquitoes exhibit ∼24 h rhythms in physiology and behavior, regulated by the cooperative action of an endogenous circadian clock and the environmental light:dark cycle. Here, we characterize diel (observed under light:dark conditions) time-of-day changes in metabolic detoxification and resistance to insecticide challenge in Anopheles gambiae mosquitoes. A better understanding of mosquito chronobiology will yield insights into developing novel control strategies for this important disease vector. We have previously identified >2000 rhythmically expressed An. gambiae genes. These include metabolic detoxification enzymes peaking at various times throughout the day. Especially interesting was the identification of rhythmic genes encoding enzymes capable of pyrethroid and/or DDT metabolism (CYP6M2, CYP6P3, CYP6Z1, and GSTE2). We hypothesized that these temporal changes in gene expression would confer time-of-day specific changes in metabolic detoxification and responses to insecticide challenge. An. gambiae mosquitoes (adult female Pimperena and Mali-NIH strains) were tested by gene expression analysis for diel rhythms in key genes associated with insecticidal resistance. Biochemical assays for total GST, esterase, and oxidase enzymatic activities were undertaken on time-specific mosquito head and body protein lysates. To determine for rhythmic susceptibility to insecticides by survivorship, mosquitoes were exposed to DDT or deltamethrin across the diel cycle. We report the occurrence of temporal changes in GST activity in samples extracted from the body and head with a single peak at late-night to dawn, but no rhythms were detected in oxidase or esterase activity. The Pimperena strain was found to be resistant to insecticidal challenge, and subsequent genomic analysis revealed the presence of the resistance-conferring kdr mutation. We observed diel rhythmicity in key insecticide detoxification genes in the Mali-NIH strain, with peak phases as previously reported in the Pimperena strain. The insecticide sensitive Mali-NIH strain mosquitoes exhibited a diel rhythm in survivorship to DDT exposure and a bimodal variation to deltamethrin challenge. Our results demonstrate rhythms in detoxification and pesticide susceptibility in An. gambiae mosquitoes; this knowledge could be incorporated into mosquito control and experimental design strategies, and contributes to our basic understanding of mosquito biology.

Daily rhythms in antennal protein and olfactory sensitivity in the malaria mosquito Anopheles gambiae.

We recently characterized 24-hr daily rhythmic patterns of gene expression in Anopheles gambiae mosquitoes. These include numerous odorant binding proteins (OBPs), soluble odorant carrying proteins enriched in olfactory organs. Here we demonstrate that multiple rhythmically expressed genes including OBPs and takeout proteins, involved in regulating blood feeding behavior, have corresponding rhythmic protein levels as measured by quantitative proteomics. This includes AgamOBP1, previously shown as important to An. gambiae odorant sensing. Further, electrophysiological investigations demonstrate time-of-day specific differences in olfactory sensitivity of antennae to major host-derived odorants. The pre-dusk/dusk peaks in OBPs and takeout gene expression correspond with peak protein abundance at night, and in turn coincide with the time of increased olfactory sensitivity to odorants requiring OBPs and times of increased blood-feeding behavior. This suggests an important role for OBPs in modulating temporal changes in odorant sensitivity, enabling the olfactory system to coordinate with the circadian niche of An. gambiae.

Unilateral pulmonary edema demonstrated with Tl-201 imaging.

Clinical and scintigraphic findings are described in a patient in whom acute right-sided pulmonary edema developed during a treadmill exercise test. The patient's SPECT Tl-201 stress images are reviewed along with the pertinent clinical history. The development of unilateral pulmonary edema during an exercise treadmill test was demonstrated with Tl-201 imaging.