Search PubMed⌕ Search

Biomedical subjects

M B Ravin

Publications and source records attributed to M B Ravin.

26 records · Page 2Linked to original sources
PubMedDate not supplied

Pyridostigmine as an antagonist of d-tubocurarine-induced and pancuronium-induced neuromuscular blockade.

In an evaluation of the clinical effectiveness of pyridostigmine as an antagonist of d-tubocurarine-induced and pancuronium-induced neuromuscular blockade in patients anesthetized with a neurolept-nitrous oxide (N2O) technic, 60 adults received either d-tubocurarine (dTc) (N equals 30) or pancuronium (N equals 30). The pancuronium-dTc potency ratio with neurolept-N2O anesthesia is 4.85:1. The mean doses of pyridostigmine necessary for 50 percent recovery of control twitch height and sustained tetanus were 5.72 plus or minus 0.45 (S.E.) mg. and 11.6 plus or minus 0.88 mg., respectively, for dTc, and 4.05 plus or minus 0.24 mg. and 8.27 plus or minus 0.41 mg., respectively, for pancuronium. There was no correlation between the amount of pyridostigmine necessary for relaxant antagonism and the total dose of relaxant used. In 24 patients, neuromuscular blockade was reversed by an intravenous injection of pyridostigmine and either 0.6 mg. or 1 mg. of atropine. Within 2 minutes, patients given 1 mg. of atropine had a significantly faster heart rate than those given 0.6 mg of atropine (p smaller than 0.0001). There was no correlation between control heart rate and maximum changes in heart rate. No cardiac arrhythmia or bronchospasm was observed in patients with either pancuronium or dTc following atropine-pyridostigmine mixtures. The cardiac muscarinic effects of pyridostigmine could be modified by simultaneous administration of 1 mg. of atropine.

Adult↗
PubMedDate not supplied

Inflammatory potential of foreign particulates in parenteral drugs.

Particulate and bacterial contamination of IV fluids and drugs have been implicated in venous thrombosis, infusion phlebitis, suppurative thrombophlebitis, pyrogenic reactions, and systemic sepsis. In a study of the inflammatory potential of the filterable residue of sodium cephalothin, we have found a tissue-specific reaction with venous endothelium but not with cutaneous or subcutaneous tissues. In a controlled animal model, removal of particulates from an infusion by use of a 0.45 micron in-line membrane filter reduces the incidence and severity of infusion phlebitis.

Animals↗
PubMedDate not supplied

Rheology and anesthesiology.

We present a review of blood rheology with special emphasis on its application in anesthesiology. The rheological behavior of blood is determined by 2 variables, non-Newtonian viscosity and yield stress. The physical significance of these quantities is discussed. Blood viscosity directly affects total peripheral resistance, and changes in the state of peripheral vessels cannot be accurately evaluated unless simultaneous measurements of blood viscosity are made. Blood viscosity also influences cardiac output, and elevations in hematocrit may reduce total O2 transport by increasing viscosity to the point that cardiac output decreases. The role of blood viscosity and blood yield stress in the pathogenesis of deep-vein thrombosis is mentioned, and the role of anesthesia in affecting viscosity by decreasing venous flow is discussed. Clinical examples of the role of blood rheology in neonatal respiratory distress and during open heart surgery are also given.

Adolescent↗