Specific effects of nitroprusside on myocardial O2 balance following coronary ligation in the dog heart

The effect of gradual infusion of nitroprusside was studied in healthy and in ischemic hearts. In two areas of the left ventricular surface (ischemic and non-ischemic) local coronary blood flow was measured by a thermistor technique. Isometric contractile tension was recorded with strain gauge arches, and nicotinamide-adenine-dinucleotide (NADH) redox state was measured simultaneously in both regions using a two-channel fluorometer. Aortic blood pressure was also recorded. It was found that at an infusion rate of 1.0 microgram/kg/min, nitroprusside increased regional coronary blood supply in the healthy heart as well as in the ischemic and nonischemic areas of left anterior descending artery (LAD)-ligated hearts. Flow elevation was similar in all regions (37.0 +/- 6.1, 42.5 +/- 13.5 and 45.36 +/- 14.8%, respectively). At higher doses, a decrease of 6-10% in blood pressure had a detrimental effect on the coronary flow to the ischemic region without reducing flow to the nonischemic region. The NADH redox level was not significantly improved by nitroprusside in spite of elevated coronary blood supply to all regions examined. Moreover, higher doses of nitroprusside resulted in a significant elevation in NADH levels that could be correlated to the decrease in blood pressure. It is concluded that the effect of nitroprusside on coronary blood supply and myocardial O2 balance may be strongly dependent on the magnitude of its effect on blood pressure.     

Patterns of Cocaine Use Among Cocaine-Dependent Outpatients

The authors systematically evaluated the frequency patterns of cocaine use in 85 cocaine-dependent outpatients and found four patterns of use: continuous (27%), intermittent patterned (35%), intermittent nonpatterned (25%), and occasional (13%). Few subjects reported consistent cycling between binges and crashes. There were no significant differences in patterns of use associated with gender, race, educational level, route of administration, or recency of heroin use. Continuous users and occasional users were older than intermittent users. Because different contingencies may control patterned vs. nonpatterned cocaine use, pattern of use may have implications for treatment, even in individuals reporting similar amounts of cocaine use.     

Development of the Massachusetts School Nurse Research Network (MASNRN): A Practice-Based Research Network to improve the quality of school nursing practice.

When school nurses embrace evidence-based practice (EBP), higher-quality care is provided to students, their families, and the larger community. Despite this, school nursing has been slow to embrace EBP. Practice-Based Research Networks (PBRNs), which capitalize on the combined strengths of clinicians and researchers to study clinical questions, are one approach to overcoming barriers towards advancing evidence-based practice (EBP) in school nursing. This article will briefly review EBP and PBRNs. The development of Massachusetts School Nurse Research Network (MASNRN), a PBRN designed to investigate health issues common across schools and to validate school nursing practice, will then be described. Details regarding MASNRN's mission, governance, communications systems, staffing, and network maintenance and funding will be explicated. MASNRN can serve as a model for PBRN development within the broader school nursing community.     

Management of infraumbilical vertical scars in DIEP-flaps by crossover anastomosis.

The deep inferior epigastric perforator (DIEP)-flap continues to be the standard treatment in microsurgical breast reconstruction. Reasons for the popularity of the DIEP-flap include the availability of a large amount of tissue for the reconstruction of large breasts, a reliable vascular anatomy and an aesthetically pleasing donor site scar. However, the DIEP-flap is not considered the optimal choice as the donor tissue in all patients. Previous abdominal surgeries with resulting scars may threaten the success of a free DIEP-flap due to compromised vascularity within the flap. We elaborated a technique to increase the safety of breast reconstruction with the DIEP-flap in the presence of an infraumbilical vertical scar. After raising the DIEP-flap in a traditional manner on one side with harvesting of a considerate length of the inferior epigastric vessels, a segment of the superior epigastric vessels is left attached to the main pedicle. This stump of the superior epigastric vessels is now anastomosed under the microscope to a paraumbilical perforator on the contralateral side of the flap for in-flap microvascular augmentation. The above-mentioned technique was applied in five patients who presented with an infraumbilical vertical scar and were reconstructed with a DIEP-flap because of breast cancer. In three of the five patients there was an additional risk factor present such as smoking or diabetes mellitus. In all five patients no major complication due to marginal perfusion of the contralateral side of the flap was encountered. In two patients there was minor breakdown of fatty tissue that was managed conservatively in both cases. In-flap microvascular augmentation of DIEP-flaps is a valuable tool for the plastic surgeon in microvascular breast reconstruction. It permits usage of the lower abdominal tissue even if perfusion is compromised due to midline scarring. We recommend this technique as a safe alternative in patients seeking autologous breast reconstruction in the presence of a midline abdominal scar.     

Local Inflammation in Rat Dorsal Root Ganglion Alters Excitability and Ion Currents in Small-diameter Sensory Neurons

Background: Chronic pain conditions may result from peripheral nerve injury, chronic peripheral inflammation, or sensory ganglia inflammation. However, inflammatory processes may also contribute to peripheral nerve injury responses. To isolate the contribution of local inflammation of sensory ganglia to chronic pain states, the authors previously developed a rat model in which long-lasting pain is induced by inflaming sensory ganglia without injuring the neurons. This results in prolonged mechanical pain, local increases in proinflammatory cytokines, increased neuronal hyperexcitability, and abnormal spontaneous activity.

Methods: The authors used whole cell patch clamp in acutely isolated small-diameter neurons to determine how localized inflammation (3-5 days) of L4 and L5 ganglia altered voltage-gated K+ and Na+ currents.

Results: Tetrodotoxin-sensitive Na+ currents increased twofold to threefold in neurons from inflamed ganglia. Tetrodotoxin-resistant Na+ currents increased more than twofold, but only in cells that bound isolectin B4. These increases occurred without shifts in voltage dependence of activation and inactivation. Similar results are seen in models of peripheral inflammation, except for the large magnitudes. Unlike most pain models, localized inflammation increased rather than decreased voltage-gated K+ currents, due to increased amplitudes of the sustained (delayed rectifier) and fast-inactivating transient components. The overall effect in current clamp experiments was an increase in excitability as indicated by decreased rheobase and lower action potential threshold.     

Immediate and delayed cord clamping in infants born between 24 and 32 weeks: a pilot randomized controlled trial.

OBJECTIVE: This pilot study's aim was to establish feasibility of a protocol for delayed cord clamping (DCC) versus immediate cord clamping (ICC) at preterm birth and to examine its effects on initial blood pressure and other outcomes. STUDY DESIGN: A randomized controlled trial recruited 32 infants between 24 and 32 weeks. Immediately before delivery, mothers were randomized to ICC (cord clamped at 5 to 10 seconds) or DCC (30- to 45-second delay in cord clamping) groups. RESULTS: Intention-to-treat analyses revealed that the DCC group were more likely to have higher initial mean blood pressures (adjusted OR 3.4) and less likely to be discharged on oxygen (adjusted OR 8.6). DCC group infants had higher initial glucose levels (ICC=36 mg/dl, DCC=73.1 mg/dl; p=0.02). CONCLUSION: The research design is feasible. The immediate benefit of improved blood pressure was confirmed and other findings deserve consideration for further study.     

Providence School Asthma Partnership: School-based Asthma Program for Inner-City Families

Over 3 years, 972 families participated in an after-school asthma program at their child's school. Parents and children attended concurrent 2¹/₂ -hour workshops. Parents were 74% Latino; 45% non-English speaking, with 77% of children on Medicaid. Asthma symptoms were significantly reduced, from multiple times per week to less than once per week on average. Oral steroid use decreased to one third of baseline use. Hospital days decreased from 11% to 2%; emergency visits decreased 35% to 4%; and school days missed decreased 48% to 20%. This program has now become sustainable with both private and Medicaid insurance coverage.