A risk score for postoperative nausea and/or vomiting in women undergoing cesarean delivery with intrathecal morphine.

BACKGROUND: Postoperative nausea and/or vomiting affects up to 80% of parturients undergoing cesarean delivery, but there is a lack of obstetric-specific risk-prediction models. We performed this study to identify postoperative nausea/vomiting risk factors in parturients undergoing cesarean delivery, formulate an obstetric-specific prediction model (Duke score), and compare its performance against the Apfel score. METHODS: A post-hoc analysis of data from two randomized controlled trials studying nausea/vomiting in women undergoing cesarean delivery with intrathecal morphine. Potential risk factors for postoperative nausea/vomiting within 24 h of surgery with univariate associations with P ≤0.20 were considered for inclusion in the multivariable analysis. After identifying the final multivariable model, we derived our Duke score by assigning points to the selected factors. We then tested the association of the Duke and Apfel scores with postoperative nausea and vomiting, and compared the area-under-the-receiver operating characteristic curve. RESULTS: Analysis included 260 parturients, of whom 146 (56.2%) experienced postoperative nausea/vomiting. Non-smoking during pregnancy (OR 2.29 [95% CI 1.12 to 4.67], P=0.023), and history of postoperative nausea/vomiting after cesarean delivery and/or morning sickness (2.09 [1.12 to 3.91], P=0.021) were independent predictors of postoperative nausea/vomiting and included in the Duke score. Both Duke and Apfel scores trended linearly with postoperative nausea/vomiting risk (Duke P=0.001; Apfel P=0.049) and had comparable areas-under-the-receiver operating characteristic curve (Duke 0.63 [0.57 to 0.70]; Apfel 0.59 [0.52 to 0.65], P=0.155). CONCLUSIONS: Both Duke and Apfel scores exhibited similar but poor predictive performance. Until better tools are developed, routine prophylactic anti-emetics appears to be a reasonable approach in this patient population.

Maresin 1 attenuates neuroinflammation in a mouse model of perioperative neurocognitive disorders.

BACKGROUND: Resolution of inflammation is an active and dynamic process after surgery. Maresin 1 (MaR1) is one of a growing number of specialised pro-resolving lipids biosynthesised by macrophages that regulates acute inflammation. We investigated the effects of MaR1 on postoperative neuroinflammation, macrophage activity, and cognitive function in mice. METHODS: Adult male C57BL/6 (n=111) and Ccr2RFP/+Cx3cr1GFP/+ (n=54) mice were treated with MaR1 before undergoing anaesthesia and orthopaedic surgery. Systemic inflammatory changes, bone healing, neuroinflammation, and cognition were assessed at different time points. MaR1 protective effects were also evaluated using bone marrow derived macrophage cultures. RESULTS: MaR1 exerted potent systemic anti-inflammatory effects without impairing fracture healing. Prophylaxis with MaR1 prevented surgery-induced glial activation and opening of the blood-brain barrier. In Ccr2RFP/+Cx3cr1GFP/+ mice, fewer infiltrating macrophages were detected in the hippocampus after surgery with MaR1 prophylaxis, which resulted in improved memory function. MaR1 treatment also reduced expression of pro-inflammatory cell surface markers and cytokines by in vitro cultured macrophages. MaR1 was detectable in the cerebrospinal fluid of older adults before and after surgery. CONCLUSIONS: MaR1 exerts distinct anti-inflammatory and pro-resolving effects through regulation of macrophage infiltration, NF-κB signalling, and cytokine release after surgery. Future studies on the use of pro-resolving lipid mediators may inform novel approaches to treat neuroinflammation and postoperative neurocognitive disorders.

The impact of gestational age and fetal weight on the risk of failure of spinal anesthesia for cesarean delivery.

BACKGROUND: There are limited data about spinal dosing for cesarean delivery in preterm parturients. We investigated the hypothesis that preterm gestation is associated with an increased incidence of inadequate spinal anesthesia for cesarean delivery compared with term gestation. METHODS: We searched our perioperative database for women who underwent cesarean delivery under spinal or combined spinal-epidural anesthesia with hyperbaric bupivacaine ⩾10.5mg. The primary outcome was the incidence of inadequate surgical anesthesia needing conversion to general anesthesia or repetition or supplementation of the block. We divided patients into four categories: <28, 28 to <32, 32 to <37 and ⩾37weeks of gestation. The chi-square test was used to compare failure rates and a multivariable regression analysis was performed to investigate potential confounders of the relationship between gestational age and failure. RESULTS: A total of 5015 patients (3387 term and 1628 preterm) were included. There were 278 failures (5.5%). The incidence of failure was higher in preterm versus term patients (6.4% vs. 5.1%, P=0.02). Failure rates were 10.8%, 7.7%, 5.3% and 5% for <28, 28 to <32, 32 to <37 and ⩾37weeks of gestation, respectively. In the multivariable model, low birth weight (P<0.0001), gestational age (P=0.03), ethnicity (P=0.02) and use of combined spinal-epidural anesthesia (P<0.0001) were significantly associated with failure. CONCLUSIONS: At standard spinal doses of hyperbaric bupivacaine used in our practice (⩾10.5mg), there were higher odds of inadequate surgical anesthesia in preterm parturients. When adjusting for potential confounders, low birth weight was the main factor associated with failure.

Transforming growth factor-beta expression in otitis media with effusion.

OBJECTIVE: To characterize the existence and role of transforming growth factor-beta (TGF-beta) in otitis media with effusion (OME). STUDY DESIGN: Retrospective. METHODS: The levels of two major TGF-beta isoforms, TGF-beta1 and TGF-beta2, in the middle ear effusions (MEEs) of 44 children were evaluated using enzyme-linked immunospecific assays (ELISAs). Forty-eight MEEs were separated into three clinically relevant groups (i.e., serous, mucoid, and purulent), and TGF-beta levels were correlated with clinical parameters of disease for these MEEs. RESULTS: Both TGF-beta1 and TGF-beta2 were present in the samples. Mean levels of TGF-beta1 (920.36 +/- 437.75 pg/mg total protein) were generally 100-fold greater than those of TGF-beta2 (9.65 +/- 11.19 pg/mg total protein). TGF-beta1 levels were elevated in association with a history of previous tympanostomy tube placements (TTPs) (P = .029) and mucoid effusions (P = .042). TGF-beta2 levels were elevated in association with a history of previous TTPs (P = .100) and chronic (i.e., serous or mucoid) effusions (P = .003). CONCLUSIONS: TGF-beta1 is present in the MEEs of children with OME. Furthermore, TGF-beta1 and TGF-beta2 levels were elevated differentially in the presence of chronic disease indicators in OME, suggesting that these isoforms may have differing roles in the inflammatory processes that characterize OME.

Fluorescence lifetime-enhanced spectral characterization of human serum.

Frequency-domain fluorescence lifetime techniques were used for the characterization of pooled human serum, including normal serum, hyperlipid serum, and sera that had been stripped of various components. Fluorescence lifetime measurements of normal human serum revealed lifetime components primarily in the regions of 10(2) ps, 1-2 ns, 4-7 ns, and 9-10 ns. Phase-resolved fluorescence spectroscopy (PRFS), a frequency-domain technique that combines spectral and lifetime information, in measurements of phase-resolved fluorescence intensity (PRFI), provided the basis for comparison of the various sera. Measurements of PRFI vs excitation wavelength and emission wavelength yield a phase-resolved excitation-emission matrix (PREEM) at a given modulation frequency. Multifrequency measurements yield a three-way excitation-emission-frequency array. The multifrequency PREEMs of the various sera were compared with each other and with the corresponding two-way excitation-emission matrices (EEMs) that are obtained using conventional, steady-state fluorescence spectroscopy. Application of matrix-based analysis techniques to the steady-state and PRFS data arrays allowed direct comparison between the two approaches. Results demonstrate the enhanced discrimination among samples that is achieved through the additional dimension of fluorescence lifetime in PRFS.