Early Findings on the Use of Clinical Pathways for Management of Unwarranted Variation in Cancer Care.

Clinical pathways have the potential to improve complex clinical decision-making in cancer care. The authors implemented pathways with customized content to assist oncologists to select treatments, aiming for an on-pathway rate of 70%-85%. Treatment decisions were captured as on or off pathway, and metrics were shared monthly with users. Oncologists were categorized into quintiles based on on-pathway performance during the first 90 days of use. On-pathway rates were then calculated for days 91-360 (N = 121). Median on-pathway quintile rates varied from 50% to 100% in the initial 90-day period. During follow-up, median on-pathway rates shifted into the prespecified goal range for all groups. Clinical pathways resulted in greater uniformity in medical oncology practice. Monthly feedback about usage, familiarity with the electronic platform, and regular content updates are some factors that may influence on-pathway rates. Clinical pathways hold promise to manage unwarranted variation in cancer care.

Complexation of metal ions, including alkali-earth and lanthanide(III) ions, in aqueous solution by the ligand 2,2',6',2''-terpyridyl.

Some metal-ion-complexing properties of the ligand 2,2',6',2''-terpyridyl (terpy) in aqueous solution are determined by following the π-π* transitions of 2 × 10(-5) M terpy by UV-visible spectroscopy. It is found that terpy forms precipitates when present as the neutral ligand above pH ∼5, in the presence of electrolytes such as NaClO(4) or NaCl added to control the ionic strength, as evidenced by large light-scattering peaks. The protonation constants of terpy are thus determined at the ionic strength (µ) = 0 to avoid precipitation and found to be 4.32(3) and 3.27(3). The log K(1) values were determined for terpy with alkali-earth metal ions Mg(II), Ca(II), Sr(II), and Ba(II) and Ln(III) (Ln = lanthanide) ions La(III), Gd(III), and Lu(III) by titration of 2 × 10(-5) M free terpy at pH >5.0 with solutions of the metal ion. Log K(1)(terpy) was determined for Zn(II), Cd(II), and Pb(II) by following the competition between the metal ions and protons as a function of the pH. Complex formation for all of these metal ions was accompanied by marked sharpening of the broad π-π* transitions of free terpy, which was attributed to complex formation affecting ligand vibrations, which in the free ligand are coupled to the π-π* transitions and thus broaden them. It is shown that log K(1)(terpy) for a wide variety of metal ions correlates well with log K(1)(NH(3)) values for the metal ions. The latter include both experimental log K(1)(NH(3)) values and log K(1)(NH(3)) values predicted previously by density functional theory calculation. The structure of [Ni(terpy)(2)][Ni(CN)(4)]·CH(3)CH(2)OH·H(2)O (1) is reported as follows: triclinic, P1, a = 8.644(3) Å, b = 9.840(3) Å, c = 20.162(6) Å, α = 97.355(5)°, ß = 97.100(5)°, γ = 98.606(5)°, V = 1663.8(9) Å(3), Z = 4, and final R = 0.0319. The two Ni-N bonds to the central N donors of the terpy ligands in 1 average 1.990(2) Å, while the four peripheral Ni-N bonds average 2.107(10) Å. This difference in the M-N bond length for terpy complexes is typical of the complexes of smaller metal ions, while for larger metal ions, the difference is reversed. The significance of the metal-ion size dependence of the selectivity of polypyridyl ligands, and the greater rigidity of ligands based on aromatic groups such as pyridyl groups, is discussed.