Unsuspected sublingual mass causing difficult intubation in an infant

A case is described of a difficult intubation in an infant presenting for cleft palate closure, due to an unsuspected sublingual mass. The report stresses the fact that multiple anomalies can coexist in an infant and contribute to difficult intubation through different mechanisms. Various airway management strategies are explored.     

Platelet-activating factor antagonist WEB-2170 inhibits lipopolysaccharide-induced, but not antiprogestin-induced, preterm cervical ripening in timed-pregnant rats

OBJECTIVE: The purpose of this study was to determine whether the platelet-activating factor antagonist WEB-2170 inhibits preterm cervical ripening induced by lipopolysaccharide or by antiprogestin RU 486. STUDY DESIGN: Timed-pregnant rats were killed on day 16 after treatment with (1) WEB-2170, lipopolysaccharide, lipopolysaccharide plus WEB-2170, or vehicle control and (2) with WEB-2170, RU 486, RU 486 plus WEB-2170, or vehicle control. Cervical ripening was assessed by light-induced fluorescence and resistance to stretch. Statistics were assessed by 1-way analysis of variance followed by Tukey-test (P <.05). RESULTS: Light-induced fluorescence and resistance to stretch were significantly lower in the lipopolysaccharide-treated and in the RU486-treated animals compared with vehicle control (lipopolysaccharide:light-induced fluorescence, 7.0+/-0.6 vs 12.8+/-0.8 [P=.001]; resistance to stretch, 0.41+/-0.03 N/mm vs 0.54+/-0.04 N/mm [P <.05]; RU486:light-induced fluorescence, 9.6+/-0.6 vs 11.7+/-0.6 [P <.05]; resistance to stretch, 0.28+/-0.06 N/mm vs 0.61+/-0.02 N/mm [P <.001]). Compared with vehicle control, WEB-2170 alone did not alter cervical light-induced fluorescence or resistance to stretch. Although WEB-2170 significantly blocked cervical ripening after lipopolysaccharide administration (light-induced fluorescence, 11.3+/-1.3 [P <.05]; resistance to stretch, 0.61+/-0.04 [P <.01]), WEB-2170 did not inhibit the RU 486-induced cervical ripening. CONCLUSION: Although infection-related cervical ripening is inhibited by platelet-activating factor antagonists, the physiologic process of cervical ripening appears to be unaffected. Platelet-activating factor inhibition may be of clinical value in the infection-related pathologic processes that are responsible for premature cervical ripening.     

Proteinase-activated receptor-2 activation induces uterine contractility in term pregnant rats that is not dependent on mast cell activation and cyclo-oxygenase products

OBJECTIVES: This study was undertaken to evaluate the effect of proteinase-activated receptor-2 (PAR-2) activation on the contractility of uterine tissues from term pregnant rats and the role of mast cells and prostaglandins in such an effect. STUDY DESIGN: Uterine rings from pregnant (day 20-21) Sprague-Dawley rats were used for isometric tension recording in organ chamber experiments (Krebs solution, 5% carbon dioxide in air, 37 degrees C, pH approximately 7.4). Responses to the PAR-2 activating peptide SLIGRL (serine-leucine-isoleucine-glycine-arginine-leucine), and to the inactive reverse peptide LRGILS (leucine-arginine-glycine-isoleucine-leucine-serine) were determined after pretreatments with compound 48/80, cromolyn, S[+]-chlorpheniramine maleate, cimetidine, combinations of histamine (H) receptor antagonists with cromolyn or ibuprofen and compared with vehicle. RESULTS: SLIGRL significantly augmented contractility of uterine tissues, and this response was not inhibited by compound 48/80, cromolyn, and ibuprofen, as well as by H(1)- and H(2)-receptor antagonists, alone or in combination with cromolyn. CONCLUSION: PAR-2 activation augments uterine contractility in tissues obtained from term pregnant rats, and this effect is independent of mast cell activation or cyclo-oxygenase pathway products.     

Flow rate-perfusion pressure relationships in situ in the uterine circulation of pregnant rats

OBJECTIVE: Our purpose was to study the effects of inhibition of nitric oxide synthesis on perfusion pressure and flow rate-perfusion pressure relationships in the rat uterine circulation in situ. STUDY DESIGN: Nonpregnant, midpregnant (day 14), and late pregnant (day 21) Sprague-Dawley rats were studied. The vascular bed of the intact uterus and its contents were isolated and perfused with Krebs buffer (37 degrees C, pH approximately 7.4, 2% dextran and indomethacin, 10(-5) mol/L) through a cannula inserted into the abdominal aorta close to the iliac artery bifurcation, and perfusion pressure was monitored. After equilibration, the flow rate was increased from 1 mL/min to 8 or 16 mL/min, in the absence and presence of N(omega)-nitro-L-arginine methyl ester (L-NAME), phenylephrine, or both. RESULTS: The flow rate-perfusion pressure relationship in midpregnant rats (n = 9) was not significantly different from that in late pregnant rats (n = 12), but the latter was significantly greater than the relationship in nonpregnant animals (n = 5). L-NAME did not influence perfusion pressure and flow rate-perfusion pressure relationships in any of the groups. However, L-NAME enhanced the phenylephrine-induced and flow rate-induced increase in perfusion pressure in the vascular beds from nonpregnant and midpregnant animals, and to a lesser extent in late pregnant rats. L-arginine did not influence perfusion pressure or the flow rate-perfusion pressure relationship in any group. CONCLUSIONS: Vasoconstriction produced by phenylephrine uncovers basal release of endothelium derived nitric oxide. Vasoconstriction increases perfusion pressure responses to increases in flow rate in the uterine vascular beds of nonpregnant, midpregnant, and late pregnant rats. The release of endothelial nitric oxide in the uterine vascular beds depends on the basal contractile state of the vasculature.     

The effect of in utero exposure to indomethacin on the need for surgical closure of a patent ductus arteriosus in the neonate

OBJECTIVE: Our purpose was to determine the effect of in utero exposure to indomethacin on the need for surgical closure of a patent ductus arteriosus (PDA). STUDY DESIGN: Perinatal variables were compared between infants at <32 weeks who required surgical closure of PDA after failed medical management and those who did not. Statistical analysis was performed by Student t, Mann-Whitney, chi(2), and multiple logistic regression tests. RESULTS: Eight of 77 infants with PDA failed therapy and required surgery. Maternal demographics, gestational age, birth weight, and delivery route were similar in both groups. In utero exposure to indomethacin was more common in neonates requiring surgery versus those who did not, particularly when exposure was for >72 hours (50.0% vs 8.7%, odds ratio 10.5, 95% CI 1.6-72.1, P =.008). CONCLUSION: Need for surgical closure of PDA appears to be increased by in utero indomethacin exposure. These findings should be considered in the overall context of the risk versus benefits of tocolysis.     

Uterine electromyography and light-induced fluorescence in the management of term and preterm labor

OBJECTIVE: Understanding the physiology of the uterus and cervix during term and preterm parturition is crucial for developing methods to control their function and is essential to solving clinical problems related to labor. To date, only crude, inaccurate, and subjective methods are used to assess changes in uterine and cervical function in pregnancy. METHODS: In the past several years, we have developed noninvasive methods to quantitatively evaluate the uterus and cervix based on recording of uterine electrical signals from the abdominal surface (uterine electromyography) and measurement of light-induced fluorescence (LIF) of cervical collagen (Collascope), respectively. Both methods are rapid and allow immediate assessment of uterine contractility and cervical ripening. RESULTS: Studies in animals and humans indicated that uterine and cervical performance can be monitored successfully during pregnancy using those approaches and that these techniques can be used during labor to better define management in a variety of conditions associated with labor. CONCLUSION: The potential benefits of the proposed instrumentation and methods include reducing the rate of preterm delivery, improving maternal and perinatal outcome, monitoring treatment, decreasing cesarean rate and providing research methods to understand uterine and cervical function.     

Imaging technique selection for the preoperative planning of oral implants: a review of the literature

Background: As the use of oral implants for the treatment of partially as well as fully edentulous patients has increased the past two decades, more specialized radiographie techniques have become available for the preoperative planning of oral implant placement. Purpose: The goal of this article was to enable clinicians to select the appropriate imaging techniques when planning for oral implants. Materials and Methods: This article reviews the available literature about various imaging techniques and their indication for the preoperative planning of oral implants. The advantages and drawbacks of each technique are described. A dosimet‐ric overview is given relative to different radiologie techniques used in various clinical situations. Results: For preoperative planning of implant placement, advantages and drawbacks of the available imaging techniques have been considered, which allows guidelines for image technique selection to be formulated based on the clinical situation provided, considering the diagnostic yield of each technique and the radiation doses involved. Conclusions: From the available literature, it can be stated that many clinical situations demand the use of cross‐sectional imaging techniques for optimal preoperative planning of implant placement. Nevertheless, such techniques are not required in cases in which the clinical examination reveals sufficient bone width and where standard radiographie examinations, such as intraoral and panoramic radiography, reveal adequate bone height and space for implant placement.     

Balloon-assisted coil placement in wide-neck bifurcation aneurysms by use of a new,compliant balloon microcatheter

Two types of balloon are usually employed to perform balloon-assisted coil placement in cerebral aneurysms: oval, guide-dependent balloons for sidewall aneurysms and round balloons for bifurcation aneurysms. We report on the use of a new, more compliant, guide-dependent oval balloon microcatheter to seal wide-neck bifurcation aneurysms with coils during endovascular occlusion.     

The L-type calcium channel blocker nimodipine mitigates "learned helplessness" in rats

We assessed the effect of nimodipine, an L-type calcium channel blocker, on the escape deficit induced by prior exposure to inescapable shock in rats in four experiments. In Experiment 1, we injected rats at each of three time points (i.e., before shock exposure, after shock exposure, and before shuttle escape testing) with one of four doses of nimodipine (0, 0.5, 2.5, 5.0 mg/kg). The 5.0-mg/kg dose was most effective, acting to reduce shuttle escape latencies of inescapably shocked rats to a level comparable with nonshocked controls. No benefit occurred in Experiment 2, however, when nimodipine was administered at only one of the three time points used in the first experiment. Moreover, escape performance did not improve when rats received injections of nimodipine on the 2 days prior the experiment, and then one additional injection at one of the three time points identified above in Experiment 3. Finally, administration of nimodipine at two of the three time points did improve escape responding, but only when injected immediately prior both to shock exposure and the shuttle escape test.     

Effect of lipopolysaccharide on uterine contractions and prostaglandin production in pregnant rats

OBJECTIVE: Our aim was to evaluate the effect of lipopolysaccharide on prostaglandin production and on contraction of isolated myometrial strips from preterm pregnant rats. STUDY DESIGN: Pregnant Wistar rats on day 17 of gestation were killed 3 hours after intraperitoneal injection of lipopolysaccharide (1.5 mg/kg) or vehicle, with or without pretreatment with indomethacin (5 mg/kg administered intraperitoneally) 1 hour beforehand. Concentrations of endotoxin in maternal serum and amniotic fluid, prostaglandin F2alpha and prostaglandin E2 in amniotic fluid, and progesterone in maternal serum were determined. Longitudinal uterine strips were prepared, placed in organ chambers with Krebs-Ringer solution, aerated with 95% oxygen and 5% carbon dioxide (37 degrees C, pH approximately 7.4), and equilibrated at 1g passive tension. Concentration-contraction relationships to oxytocin were determined. Samples of bathing solution were collected 10 minutes after the concentration of oxytocin was maximal. Prostaglandins and progesterone were measured by radioimmunoassay and endotoxin was measured by the Endospecy (Seikagaku Kogyo, Tokyo, Japan) kit. RESULTS: Lipopolysaccharide treatment significantly increased the levels of prostaglandin F2alpha and prostaglandin E2 in amniotic fluid. Treatment with lipopolysaccharide inhibited the production and release of prostaglandin F2alpha and prostaglandin E2 that were activated by oxytocin in uterine strips and increased the sensitivity of strips to the contractile effect of oxytocin. Indomethacin did not affect the basal or the lipopolysaccharide-activated levels of endotoxin in serum and amniotic fluid and exerted a counteraction on lipopolysaccharide-induced increases in concentrations of prostaglandin F2alpha and prostaglandin E2 in amniotic fluid. Indomethacin counteracted oxytocin-activated production and release of prostaglandin F2alpha and prostaglandin E2 in uterine tissues after lipopolysaccharide administration without changing the sensitivity of uterine strips to oxytocin. Concentrations of progesterone were not changed after lipopolysaccharide, indomethacin, or their combined application, which suggests that the changes described were not associated with alterations in the levels of the hormone. CONCLUSIONS: The activation of the uterine contractile system by prostaglandin and oxytocin during intra-amniotic infection may be one of the causes of preterm delivery. A combination of an oxytocin receptor antagonist and an inhibitor of cyclooxygenase may be beneficial in prevention or treatment of preterm labor.