Randomized comparative trial of three antivenoms in the treatment of envenoming by lance-headed vipers (Bothrops jararaca) in Sao Paulo, Brazil

In São Paulo City, Brazil, 121 patients with moderatelysevere envenoming by Bothrops snakes (principally B. jararaca)were randomized for treatment with Brazilian polyspecific Bothropsantivenoms: Instituto Butantan (39 patients), Instituto VitalBrazil (41), Fundação Ezequiel Dias (FUNED) (41).The initial dose was four ampoules (40 ml) in 89 patients withless severe envenoming and eight ampoules (80 ml) in 32 patientswith more severe envenoming. A second dose of four ampouleswas required in 20 patients. Patients receiving the three antivenoms were comparable in allrespects before treatment There were no deaths. The majorityshowed rapid clinical improvement, resolution of local envenoming,cessation of bleeding and restoration of blood coagulability.No differences in the efficacy of the three antivenoms wererevealed by clinical or laboratory observations, including measuresof haematological, haemostatic and biochemical ab normalities.Twelve patients developed abscesses (Butantan 1, Vital Brazil6, FUNED 5) and seven developed local necrosis (3,1,3). Of 88patients followed up 20–30 days after the bite 33 (37.5%)still had symptoms or signs of local envenoming, especiallyswelling. Early (anaphylactic) reactions were unexpectedly frequent afterall three antivenoms but were significantly more frequent withButantan (87%) than with Vital Brazil (37%) or FUNED (56%) antivenoms(p < 0.001). A possible explanation was the higher totalprotein content and percentage immunoglobulin of Butantan antivenom. The doses of antivenom recommended in Brazil and used in thisstudy may be unnecessarily high, resulting in an unacceptablyhigh incidence of reactions. Results of the study should prompta critical re-evaluation of antivenom production techniquesand dosage recommendations in Brazil.     

Low‐Dose Heparin for Elective Percutaneous Coronary Intervention

Objectives

We evaluated the safety and efficacy of low‐dose heparin (40 IU/kg) for elective percutaneous coronary intervention (PCI).

Background

Current guidelines recommend a 70–100 IU/kg bolus of heparin for elective PCI, but this dose may be associated with increased bleeding risk. Low‐dose heparin may have an advantage in this regard, but has not been well studied.

Methods

From January 2008 to October 2012, 300 patients underwent elective transfemoral PCI and were treated with an initial bolus of 40 IU/kg of heparin at the UCLA Medical Center. Dual antiplatelet therapy with clopidogrel and aspirin was administered prior to or just after diagnostic coronary angiography. The primary end‐point was the composite of cardiac death, myocardial infarction, urgent target vessel revascularization for ischemia, or major bleeding within 30 days after PCI.

Results

The mean activating clotting time was 233 ± 28 seconds. The primary end‐point occurred in 2.3%. The cardiac death rate was 0.3% but was not related to the PCI. The myocardial infarction rate was 1.3%. Urgent target vessel revascularization occurred in 1 patient (0.3%). The major bleeding rate was 0.3%. No stent thrombosis occurred.

Conclusion

Using a lower dose of heparin with dual antiplatelet therapy is safe and is associated with a low bleeding risk after transfemoral PCI while providing suppression of ischemic events. This may also represent a cost savings compared with other antithrombotic strategies. A randomized clinical trial comparing low‐dose heparin with bivalirudin in patients is required to determine the optimal anticoagulation strategy. (J Interven Cardiol 2014;27:58–62)

     

The effect of glycerol on the guinea-pig hydropic ear

The aim of this paper was to investigate the effect of glycerol on experimental endolymphatic hydrops in guinea-pigs. The right endolymphatic sac and duct were obliterated through an extradural posterior fossa approach. Some animals received a 3 g/kg dose of glycerol for a period of 7 days, whereas others received the same dose for 30 days. The activity of glycerol was studied by investigating the volumetric changes in the scala media determined with a computerized planimeter. Glycerol induced a significant reduction of the hydrops showing its effectiveness and suggesting a strial metabolic response.     

Anomalous Mitral Arcade: Echocardiographic and Color Flow Findings

A patient with surgically confirmed anomalous mitral valve arcade was noninvasively studied. Two-dimensional echocardiography clearly visualized the "arcade" shape and Doppler color flow mapping was useful in assessing hemodynamics. (ECHOCARDIOGRAPHY, Volume 8, November 1991)