Spinal Hypotension and Time from Spinal-to-Delivery in Scheduled Cesarean Deliveries: Association with Neonatal Acidosis.

OBJECTIVE: This work aimed to study the effect of sustained hypotension after spinal on neonatal acidosis and adverse outcomes in those undergoing scheduled cesarean delivery (CD) with universal prophylactic vasopressor exposure and to examine differences in spinal-to-delivery time by neonatal acidosis status. STUDY DESIGN: This retrospective cohort study conducted at a quaternary care center from January 2019 to December 2021 included singleton, term, nonanomalous pregnancies, with scheduled CD under spinal anesthesia. Hypotension was defined as a systolic blood pressure (SYS-BP) < 100 mm Hg (SYS-BP100) or a >20% drop from baseline blood pressure (SYS-BP20). Both the occurrence of hypotension and its magnitude and duration were studied; the latter through the development of a hypotension index. The 90th and 95th percentiles of the hypotension index for SYS-BP20 and SYS-BP100, respectively, were used to define sustained hypotension. The primary outcome was neonatal acidosis (umbilical artery pH ≤ 7.1 or base excess ≤ -12 mmol). Secondary outcomes were composites of neonatal (CNAO) and maternal (CMAO) adverse outcomes. Multivariable Poisson regression models with robust error variance analysis was used to estimate adjusted relative risks (aRRs) and 95% confidence intervals (CIs). RESULTS: Our study included 332 individuals who underwent scheduled CD; among them 330 (99.4%) received prophylactic vasopressors. The rate of neonatal acidosis was 4.2%. Sustained hypotension after spinal anesthesia, which occurred in 12.3% of the cohort, was associated with increased risk for neonatal acidosis (aRR 3.96, 95% CI 1.21-12.98), but was not associated with CNAO or CMAO. Time from spinal-to-delivery was not different in those with and without neonatal acidosis. CONCLUSION: Despite universal exposure to prophylactic vasopressors, sustained hypotension after spinal anesthesia was still associated with neonatal acidosis, but no other adverse perinatal outcomes. Our findings may provide additional support for the adoption of prophylactic vasopressors to reduce spinal hypotension and downstream effects on the neonate from intraoperative hemodynamic instability. KEY POINTS: · Despite prophylactic vasopressors during scheduled CD, neonatal acidosis occurred in 4% of subjects.. · Sustained hypotension after spinal anesthesia was associated with neonatal acidosis, but not adverse neonatal outcomes.. · Spinal-to-delivery time was not associated with neonatal acidosis in scheduled CD..

Estimating the probability of illness due to swimming in recreational water with a mixture of human- and gull-associated microbial source tracking markers.

Beaches often receive fecal contamination from more than one source. Human sources include untreated sewage as well as treated wastewater effluent, and animal sources include wildlife such as gulls. Different contamination sources are expected to pose different health risks to swimmers. Genetic microbial source tracking (MST) markers can be used to detect bacteria that are associated with different animal sources, but the health risks associated with a mixture of MST markers are unknown. This study presents a method for predicting these health risks, using human- and gull-associated markers as an example. Quantitative Microbial Risk Assessment (QMRA) is conducted with MST markers as indicators. We find that risks associated with exposure to a specific concentration of a human-associated MST marker (HF) are greater if the HF source is untreated sewage rather than treated wastewater effluent. We also provide a risk-based threshold of HF from untreated sewage at a beach, to stay below a predicted illness risk of 3 per 100 swimmers, that is a function of gull-associated MST marker (CAT) concentration.

Transport of Fecal Indicators from Beach Sand to the Surf Zone by Recirculating Seawater: Laboratory Experiments and Numerical Modeling.

Recirculating seawater is an important component of submarine groundwater discharge, yet its role in transporting microbial contaminants from beach sand to coastal water is unknown. This study investigated the extent to which recirculating seawater carries fecal indicators, Enterococcus and bird-associated Catellicoccus, through the beach subsurface. Laboratory experiments and numerical modeling were performed to characterize the transport of fecal indicators suspended in seawater through medium-grained beach sand under transient and saturated flow conditions. Enterococcus was measured both by culture (cENT) and DNA assay (tENT), and Catellicoccus (CAT) by DNA assay. There were differences between transport of tENT and CAT compared to cENT through laboratory columns containing beach sands. Under transient flow conditions, first-order attachment rate coefficients (katt) of DNA markers were greater (∼10 h-1) than katt of cENT (∼1 h-1), although under saturated conditions katt values were similar (∼1 h-1). First-order detachment rate coefficients, kdet, of DNA markers were greater (∼1 h-1) than kdet of cENT (∼0.1h-1) under both types of flow conditions. Incorporating the rate coefficients into field-scale subsurface transport simulations showed that, in this sand type, the contribution of recirculating seawater to surf zone contamination is likely to be minimal unless bird feces are deposited close to the land-sea interface.

Transport of enterococci and F+ coliphage through the saturated zone of the beach aquifer.

Coastal groundwater has been implicated as a source of microbial pollution to recreational beaches. However, there is little work investigating the transport of fecal microbes through beach aquifers where waters of variable salinity are present. In this study, the potential for fecal indicator organisms enterococci (ENT) and F+ coliphage to be transported through marine beach aquifers was investigated. Native sediment and groundwaters were collected from the fresh and saline sections of the subterranean estuary at three beaches along the California coast where coastal communities utilize septic systems for wastewater treatment. Groundwaters were seeded with sewage and removal of F+ coliphage and ENT by the sediments during saturated flow was tested in laboratory column experiments. Removal varied significantly between beach and organism. F+ coliphage was removed to a greater extent than ENT, and removal was greater in saline sediments and groundwater than fresh. At one of the three beaches, a field experiment was conducted to investigate the attenuation of F+ coliphage and ENT down gradient of a septic leach field. ENT were detected up to 24 m from the leach field. The column study and field observations together suggest ENT can be mobile within native aquifer sediments and groundwater under certain conditions.

Comparative decay of Catellicoccus marimmalium and enterococci in beach sand and seawater.

Most studies characterize microbial source tracking (MST) target performance using sensitivity and specificity metrics. However, it is important to also consider the temporal stability of MST targets in relation to regulated microbial pollutants. Differences among bacterial target stabilities may lead to erroneous conclusions about sources of contamination. The present study evaluates the relative stability of MST targets and fecal indicator organisms using the gull/pigeon-associated Catellicoccus marimammalium (CAT) marker and enterococci (ENT). The decay rates of CAT and ENT measured by culture (cENT) and QPCR (tENT) were compared in sand and seawater laboratory microcosms under environmentally relevant conditions (subject to tidal wetting versus no wetting in sand, and sunlit versus dark conditions in seawater). Bacterial targets were more persistent in beach sand than in seawater with decay rates on the order of 0.01-0.1 per day and 1 to 10 per day, respectively. Targets were more persistent in unwetted compared to wetted sand, and dark compared to sunlit seawater. During the first 8 days of the sand experiment, the decay rate k of CAT was greater than that of cENT. The decay rates of CAT, tENT, and cENT were similar in sand after day 8 and in dark seawater. In sunlit seawater, the decay rates were different between targets with kcENT > kCAT > ktENT. The decay rates presented here are useful for fate and transport models and also inform the use of MST marker concentrations to infer ENT sources in the environment.

Advanced esophageal cancer in patients who underwent radiofrequency ablation for barrett esophagus with high-grade dysplasia.

OBJECTIVE: We sought to evaluate clinicopathologic features of patients who underwent esophageal surgery after radiofrequency ablation (RFA) treatment using the HALO system for Barrett esophagus (BE) with high-grade dysplasia (HGD). METHODS: We evaluated patients from our hospital database who underwent esophagectomy from August 2006 to January 2012 after previously receiving RFA for BE. Information on demographics, time between RFA and surgery, indications for surgery, and final esophageal pathology was collected. RESULTS: In our study, we selected 102 patients who underwent esophagectomy. Five patients had a history of RFA for BE with HGD. Three patients were referred because of persistent HGD despite RFA, and all three patients had HGD in the esophagectomy specimen. Two patients presented with a benign diagnosis (esophageal perforation and leiomyoma), and both of these patients had pathologic stage T3N2M0 adenocarcinoma of the esophagus in the resected specimen. One of these patients had normal mucosa overlying carcinoma in the muscularis propria and adventitia. The patients with stage T3N2M0 cancer did not have pre-RFA endoscopic ultrasound, first treatment of RFA with HALO, or surveillance endoscopic biopsy every 3 months. CONCLUSIONS: Radiofrequency ablation for BE with HGD may mask underlying esophageal cancer. Patients who are counseled to undergo RFA for HGD should be aware that RFA could lead to delayed diagnosis and delayed treatment of invasive esophageal cancer without careful patient selection, appropriate RFA use, and close surveillance.

Pheromone components from body scales of female Anarsia lineatella induce contacts by conspecific males.

Pheromonal communication of adult peach twig borers, Anarsia lineatella Zeller (Lepidoptera: Gelechiidae), was reinvestigated based on recent findings that virgin female-baited traps were more attractive to mate-seeking males than a two-component synthetic sex pheromone consisting of (E)-5-decen-1-yl acetate (1000 microg) and (E)-5-decen-1-ol (100 microg), suggesting that females use additional pheromone components. Hypothesizing that these additional components may be released from body parts other than abdominal sex pheromone glands, we extracted female body scales and analyzed aliquots by coupled gas chromatographic-electroantennographic detection (GC-EAD) and GC-mass spectrometry. Eight straight-chain and four methylated aliphatic hydrocarbons, as well as two acetates, all elicited responses from excised male antennae. In laboratory experiments with synthetic candidate pheromone components, a combination of octadecyl acetate, (R)-11-methyltricosane, and (S)-11-methyltricosane in the presence of gland-derived sex pheromone components were shown to elicit contact of female decoys by males. However, body pheromone components did not enhance attractiveness of sex pheromone components in field trapping experiments, suggesting that they are effective only at close range and that other stimuli are responsible for superior attractiveness of female-baited traps.