Effects of subconjunctival ropivacaine, liposomal bupivacaine, and mepivacaine on corneal sensitivity in healthy horses.

OBJECTIVE: To evaluate corneal sensitivity and adverse events following subconjunctival administration of three local anesthetics in horses. STUDY DESIGN: Randomized, masked, crossover study. ANIMALS: Twelve healthy adult mares. METHODS: The subconjunctival space of the treated eye was injected with 0.2 mL of liposomal bupivacaine (1.3%), ropivacaine (0.5%), or mepivacaine (2%). All horses received each medication once and the contralateral eye received saline (control). Corneal touch threshold (CTT) was measured using a Cochet-Bonnet esthesiometer before sedation, after sedation, and at specified intervals until it returned to baseline. Ocular examinations were performed at 24-, 72, and 168 h post-injection to monitor for adverse effects. RESULTS: The mean total time of anesthesia (TTA) was 168.3 min for ropivacaine, 169.2 min for liposomal bupivacaine, 103.3 min for mepivacaine and 30.7 min for the control. TTA for liposomal bupivacaine (p < .001) and ropivacaine (p = .001) was longer than the control. TTA for mepivacaine was not different from the control (p = .138), liposomal bupivacaine (p = .075) or ropivacaine (p = .150). Injection site hemorrhage reduced TTA regardless of treatments (p = .047). No adverse effects attributed to injections were noted. CONCLUSION: All three medications were well tolerated. Subconjunctival administration of ropivacaine and liposomal bupivacaine resulted in longer TTAs compared to the control; however, their TTAs were not different from that of mepivacaine. CLINICAL SIGNIFICANCE: Subconjunctivally administered liposomal bupivacaine and ropivacaine are viable options to provide prolonged corneal analgesia in horses. Future studies are needed to assess the efficacy in diseased eyes.

Biomechanical Comparison of a Headless Compression Screw Fastener and AO Cortical Bone Screw for Fixation of a Simulated Equine Third Carpal Bone Slab Fracture.

Frontal plane slab fractures account for the majority of third carpal bone (C3) fractures in racing and performance horses. Recommended treatment is stabilization with a lagged AO cortical screw. Associated complications are fragment splitting, fragment spinning, and irritation of dorsal soft tissue structures. A novel, headless, cannulated screw with interlocking threads the Headless Compression Screw Fastener (HCSF) has been developed to resist multidirectional forces and bending moments; however, it has not been applied in the horse. Simulated C3 frontal plane slab fractures were created in nine paired carpi from equine cadaver limbs, fixed with either the HCSF or AO cortical bone screw, and loaded in shear to failure. The effect of screw type on stiffness, maximum load to failure, and yield load was assessed in separate linear mixed models. No significant (P< .05) difference between screw types was detected in terms of maximum load to failure (P= .084), stiffness (P= .26), or yield load (P= .088). Mode of failure was screw bending in all specimens. For some samples in both groups, failure was associated with the sagittal fracture at the screw-bone interface. The HCSF was successfully used to repair simulated third carpal bone fractures. The different head and thread pitches of the HCSF effectively compressed the fracture. The headless design eliminates the need for counter sinking. There was no significant difference in maximum load to failure, stiffness, nor yield load compared to the cortical screws. These results invite clinical application to be investigated.

Synovial butorphanol concentrations and mechanical nociceptive thresholds after intravenous regional limb perfusion in standing sedated horses.

OBJECTIVE: To determine synovial butorphanol concentrations and mechanical nociceptive threshold (MNT) changes after butorphanol intravenous regional limb perfusion (IVRLP). STUDY DESIGN: Experimental ANIMALS: Six adult horses. METHODS: Cephalic IVRLP was performed with 10 mg butorphanol in sedated horses with a wide rubber tourniquet and a total volume of 30 mL. Radiocarpal synovial fluid and serum concentrations along with MNT were evaluated prior to and 0.5, 1, 2, 4, and 6 hours after IVRLP. Butorphanol concentrations were determined with liquid chromatography coupled to tandem mass spectrometry positive electrospray ionization. RESULTS: Butorphanol concentrations reached mean (SD) peak concentrations of 9.47 ng/mL (±12.00) in synovial fluid and 3.89 ng/mL (3.29) in serum 30 minutes after IVRLP. Concentrations remained above baseline for 4 hours in synovial fluid (P ≤ .017) and for 2 hours in serum (P ≤ .016). The only difference in MNT was detected 1 hour after IVRLP, when MNT were higher in controls than in treated horses (P = .047). CONCLUSION: Butorphanol IVRLP seemed well tolerated and resulted in measurable levels of butorphanol in the radiocarpal synovial fluid of five of six horses. CLINICAL SIGNIFICANCE: Intravenous regional limb perfusion appears to be a viable alternative to administer butorphanol, but additional investigation is required to evaluate the dose and local concentrations required for analgesia.

Changing trends in pregnancy registration for New Zealand women.

INTRODUCTION: Early pregnancy registration is recommended and provides an opportunity for screening, risk assessment and health promotion. AIM: To determine the gestation at pregnancy registration for a cohort of pregnant New Zealand women who received maternity care from a midwife Lead Maternity Carer (LMC) and to determine if women are registering earlier in pregnancy. METHODS: The gestation of pregnancy at registration was reviewed for the 81,821 women who registered with a midwife LMC between 2008 and 2010 and had data recorded in the New Zealand College of Midwives Clinical Outcomes Research Database (COMCORD). RESULTS: Over the three-year period, there was a trend towards earlier registration with 22.0% of women registering before 10 weeks' gestation in 2008 increasing to 29.9% in 2010. Women of New Zealand European ethnicity were more likely to register before 10 weeks' gestation compared to women who identified as Maori or Pacific ethnicity. Women under 20 or over 40 years of age were more likely to register in the second or third trimester than other age groups. DISCUSSION: Groups that were slower to register with a midwife LMC were women under 20 years or over 40 years of age and women of Maori or Pacific ethnicity. These groups have higher perinatal mortality rates, higher rates of smoking and lower uptake of antenatal Down syndrome screening. Further research is required to explore the barriers to earlier registration for these groups.

Delineation of pulmonary airway fluid protein fractions with HRPO binding-avidity by far-Western ligand blot and mass spectrometry analyses: a model methodology for detecting mannose-binding protein expression profiles.

BACKGROUND AND AIM OF WORK: Limited research to date has characterized the potential for HRPO to function as a primary molecular probe. METHODS: Pulmonary airway fluid was developed by non-reducing far-Western (ligand) blot analyses utilizing conjugated HRPO-strepavidin or non-conjugated HRPO without the presence of primary immunoglobulin. Endogenous esterase-like biochemical activity of fractions within pulmonary airway fluid was inactivated to determine if they were capable of biochemically converting HRPO chemiluminescent substrate. Complementary analyses modified pulmonary fluid and HRPO with beta-galactosidase and alpha-mannosidase respectively, in addition to determining the influence of mannose and maltose competitive binding on HRPO far-Western (ligand) blot analyses. Identification of pulmonary fluid fractions detected by HRPO far-Western blot analyses was determined by mass spectrometry. RESULTS: Modification of pulmonary fluid with beta-galactosidase, and HRPO with alpha-mannosidase in concert with maltose and mannose competitive binding analyses altered the intensity and spectrum of pulmonary fluid fractions detected by HRPO far-Western blot analysis. Identity of pulmonary airway fluid fractions detected by HRPO far-Western (ligand) blot analysis were transferrin, dynein, albumin precursor, and two 156 kDa equine peptide fragments. CONCLUSIONS: HRPO can function as a partially-selective primary molecular probe when applied in either a conjugated or non-conjugated form. Some protein fractions can form complexes with HRPO through molecular mechanisms that involve physical interactions at the terminal alpha-mannose-rich regions of HRPO glycan side-chains. Based on its known molecular composition and structure, HRPO provides an opportunity for the development of diagnostics methodologies relevant to disease biomarkers that possess mannose-binding avidity.

The prevention of early-onset neonatal group B streptococcus infection: technical report from the New Zealand GBS Consensus Working Party.

AIMS: Early-onset neonatal group B streptococcus (GBS) is the leading infectious cause of disease in newborn babies. Since intrapartum antibiotics interrupt vertical GBS transmission, this is now a largely preventable public health problem. An important first step is to develop (then implement) nationally, agreed prevention policies. METHODS: Representatives from the New Zealand College of Midwives, the Paediatric Society of New Zealand, the New Zealand Committee of the Royal Australian and New Zealand College of Obstetricians and Gynaecologists, the Royal New Zealand College of General Practitioners, and the Homebirth Association met to review evidence that will assist in the formulation of GBS prevention policies that are most suitable for New Zealand. RESULTS: The Technical Working Group noted that (i) no strategy will prevent all cases of early-onset GBS infection, (ii) intrapartum antibiotics are associated with rare, but serious, adverse effects, (iii) concerns remain over developing antibiotic resistance, (iv) an economic analysis is required to help inform policy, (iv) reliable bedside diagnostic tests for GBS in early labour are not yet available and (iv) the most important determinant of effectiveness will be compliance with a single national prevention policy. CONCLUSIONS: As an interim measure a GBS risk-based prevention strategy is recommended. This exposes the least numbers of women and their babies to antibiotics, while virtually preventing all deaths from GBS sepsis. Continuing education of health professionals and pregnant women, auditing protocol compliance, tracking adverse events amongst pregnant women, and national surveillance of neonatal sepsis and mortality rates and antibiotic resistance are necessary for the strategy's success.

A biomechanical comparison of headless tapered variable pitch compression and ao cortical bone screws for fixation of a simulated midbody transverse fracture of the proximal sesamoid bone in horses.

OBJECTIVE: To compare mechanical properties and failure characteristics of 2 methods of fixation for repair of a transverse, midbody fracture of the proximal sesamoid bone (PSB): 4.5-mm AO cortical bone screw (AO) placed in lag fashion and 4/5-mm Acutrak (AT) self-compressing screw. STUDY DESIGN: An in vitro biomechanical evaluation of intact forelimb preparations and forelimb preparations with a simulated midbody PSB fracture stabilized by a bone screw. SAMPLE POPULATION: Sixteen paired and 8 unilateral cadaveric equine forelimbs. METHODS: A midbody transverse osteotomy was created in the medial PSB of bilateral forelimbs of 8 equine cadavers. The osteotomized PSB in 1 forelimb from each cadaver was repaired with an AO screw. The osteotomized PSB in each contralateral limb was repaired with an AT screw. Eight unilateral intact control limbs were also studied. Mechanical properties were determined from axial compression, single cycle to failure, load-deformation curves. Failure characteristics were determined by evaluation of video images and radiographs. RESULTS: No statistically significant differences were found between repair groups. Both AO and AT groups had significantly lower mechanical properties than intact limbs except for stiffness. CONCLUSION: AO and AT constructs were mechanically comparable when used to stabilize a simulated midbody fracture of the medial PSB. Both constructs were mechanically inferior to intact limbs. Clinical Relevance- The AT screw should be considered for clinical use because of the potential for less soft tissue impingement and superior biocompatibility compared with the stainless-steel AO screw. However, postoperative external coaptation is necessary to augment initial fracture stability for either fixation method, and to maintain a standing metacarpophalangeal joint dorsiflexion angle between 150 degrees and 155 degrees.