Ultrasound determination of the dural sac to sacrococcygeal membrane distance in premature neonates.

BACKGROUND: Caudal epidural analgesia is the most common regional anesthetic performed in infants. Dural puncture, the most common serious complication, is inversely proportional to age. Measuring the distance from the sacrococcygeal membrane to the dural sac may prevent dural puncture. This study measures the sacrococcygeal membrane to dural sac distance using ultrasound imaging to determine feasibility of imaging and obtaining measurements. METHODS: Sacral ultrasound imaging of 40 preterm neonates was obtained in left lateral decubitus, a typical position for caudal blockade. No punctures were made. The sacrococcygeal membrane and termination of the dural sac were visualized, and the distance measured. The spinal levels of the conus medullaris and dural sac termination were recorded. RESULTS: 20 males and 20 females former preterm neonates with an average weight (SD; range) of 1740 (290; 860-2350) g and average age (SD; range) of 35.0 (1.35; 32.2-39) weeks gestational age at the time of imaging. The average sacrococcygeal membrane to distal dural sac distance (SD; range) was 17.4 (3.1; 10.6-26.3) mm. Overall, the weights correlated positively with the distance but the coefficient of variation was large at 23%. The conus medularis terminated below the L3 level and dural sac below the S3 level in 20% and 10% of subjects respectively with hip flexion. CONCLUSION: Ultrasound can be used to measure the sacrococcygeal membrane to dura distance in preterm neonates prior to needle insertion when performing caudal block and demonstrates large variability. Ultrasound imaging may identify patients at risk for dural puncture. When ultrasound is not available, needle insertion less than 3 mm/kg beyond the puncture of the sacrococcygeal membrane should prevent dural contact in 99.9% of neonates.

Effect of oropharyngeal colostrum therapy in the prevention of necrotising enterocolitis among very low birthweight neonates: A meta-analysis of randomised controlled trials.

BACKGROUND: Necrotising enterocolitis (NEC) is one of the most common life-threatening emergencies of the gastrointestinal tract in preterm neonates. The present study aimed to determine the efficacy of oropharyngeal colostrum with respect to reducing NEC in preterm neonates. METHODS: A literature search was conducted for various randomised control trials by searching the Cochrane Central Register of Controlled Trials, PubMed, EMBASE and ongoing clinical trials. Randomised or quasi-randomised trials comparing oropharyngeal colostrum versus placebo in neonates (birthweight ≤ 1500 g or gestational age ≤ 32 weeks) were included in the review. The methodological quality of each trial was independently reviewed by the authors. For categorical and continuous variables, typical estimates for relative risk and typical estimates for weighted mean difference were calculated, respectively. A random effect model was assumed for meta-analysis. RESULTS: In total, four eligible trials were included in the review. Oropharyngeal colostrum therapy was not associated with a statistically significant reduction in the incidence of NEC stage ≥2 [typical relative risk (RR) = 0.64; 95% confidence interval (CI) = 0.27-1.49], mortality from any cause (typical RR = 0.86; 95% CI = 0.15-4.80) and time to reach full feed [typical weighted mean difference (WMD) = -3.26; 95% CI = -8.87 to 2.35]. Duration of hospital stay was significantly less in the control group (typical WMD = 9.77; 95% CI = 3.96-15.59). CONCLUSIONS: The current evidence is insufficient for recommending oropharyngeal colostrum as a routine clinical practice in the prevention of NEC. We emphasise the need for large randomised controlled trials with an adequate sample size and validated clinical outcomes in preterm neonates.

Life history and ecology of the elusive European short-snouted seahorse Hippocampus hippocampus.

To improve the understanding of the life history and ecology of one of Europe's most elusive fishes, the short-snouted seahorse Hippocampus hippocampus, data from wild populations in a shallow coastal lagoon in southern Portugal were analysed. The data were collected from 17 tagged seahorses on a focal-study grid as well as from >350 seahorses encountered during underwater visual surveys and a fishery-independent study using beach seines. These populations of settled juveniles and adults had a mean population density of 0·009 m-2 . During the study period (2000-2004), reproduction peaked in July and August. Juveniles recruited to the lagoon at c. 66 mm standard length (LS ) and 0·5 years of age and established small home ranges (0·8 to 18·2 m2 ). First reproduction was estimated at 100 mm and 1 year of age. Based on a fitted von Bertalanffy model, H. hippocampus grew quickly (growth coefficient K = 0·93) to a maximum theoretical size L∞ = 150 mm and have a maximum lifespan of c. 3·2 years. Courtship behaviours were consistent with the maintenance of pair bonds and males brooded multiple batches of young per year. Estimated annual reproductive output averaged 871 young (±632). Together these analyses provide the first life-history parameters for this species and indicate that H. hippocampus bears characteristics of opportunist and intermediate strategists. Such populations are predicted to exhibit large fluctuations in abundance, making them vulnerable to extended periods of poor recruitment.

Arterial hypotension and prerenal failure in an extremely preterm infant associated with oral sildenafil.

We report significant hypotension and prerenal failure in an extremely preterm infant following two doses of oral sildenafil that warranted discontinuation of the drug and treatment with inotropes. Blood pressure and urine output normalized after 24 h of withdrawal of the oral drug. Sildenafil should be used cautiously in extremely preterm infants early in the neonatal course, where there is limited data on its efficacy and safety.

Species differences in testicular and hepatic biotransformation of 2-methoxyethanol.

Biotransformation of 2-methoxyethanol (2-ME) by alcohol and aldehyde dehydrogenases is an established factor in the toxicity of this useful solvent. Little is known about potential capacity for 2-ME biotransformation by testis or other target tissues. We detected appreciable capacity for 2-ME biotransformation by alcohol dehydrogenase in testes from Sprague-Dawley rats. However, kinetic analysis showed a 6-fold lower affinity for 2-ME by alcohol dehydrogenase of testis compared to liver. 2-ME biotransformation was also detected in testes from Wistar rats and one strain of mice but not in testes from hamsters, guinea pigs, rabbits, dogs, cats or humans. Testes from all these species readily converted the aldehyde metabolite of 2-ME to 2-methoxyacetic acid. Hepatic capacities for 2-ME biotransformation by alcohol dehydrogenase varied from 22 to 2.5 mumol/mg prot/min with a species rank order of: hamsters >> rats = mice > guinea pigs = rabbits. There was no consistent concordance between activities for 2-ME versus ethanol, the prototype substrate for alcohol dehydrogenase, which could reflect substrate preferences of different isozymes. Species differences between rats and hamsters were also found for testicular and hepatic biotransformation of the glycol ethers, 2-ethoxyethanol and 2-butoxyethanol. Although species differences in capacity for 2-ME biotransformation were found, the observations do not provide an explanation for reported species and strain differences in susceptibility to 2-ME toxicity.