High dose morphine use in the hospice setting. A database survey of patient characteristics and effect on life expectancy.

BACKGROUND: Pain control is one of the most important goals of end-of-life care, and the use of opioids for this purpose is extremely common in hospice settings. However, it is unknown how many of the patients require high dose morphine (HDM, >299 mg/day of oral morphine equivalent), what the characteristics of these patients are, and whether the use of HDM might affect their survival. METHODS: The authors retrospectively studied the medical records of all 651 inpatients hospitalized at their center between January 1996 and December 1997. Information was collected regarding demographic parameters, medical diagnosis, pain mechanism, morphine dosage, use of rescue doses in addition to regular doses, use of coanalgesics and adjuvant treatments, and survival time in the hospice setting as associated with morphine dosage. RESULTS: The authors identified 453 patients (69.58%) who received morphine for pain relief, of whom 55 (12.14%) needed more than 299 mg/day. Morphine dosage was negatively associated with age (r = -0.35, P = 0.01). Male patients and nonwhite patients required slightly higher dosages than others. Primary breast and genitourinary cancers, as well as metastases to bone and spinal diseases, were associated with higher morphine dosages. Statistical analysis indicated a positive correlation between the log maximum of morphine dosage and the total number of rescue dosages (r = 0.307, P = 0.025). The median survival of patients on HDM was 15.6 days and did not differ from the survival of patients taking a lower dosage. CONCLUSIONS: A fairly strong correlation exists between morphine dosage and some clinicodemographic data. No significant dose-limiting adverse effects were observed, suggesting a high clinical safety profile. High morphine dosage does not affect patient survival. Awareness of the dosage factors will improve our ability to treat and predict probable HDM dosage, thus shortening the period until pain relief is reached.

Measurement of the rate of nu(e) + d --> p + p + e(-) interactions produced by (8)B solar neutrinos at the Sudbury Neutrino Observatory.

Solar neutrinos from (8)B decay have been detected at the Sudbury Neutrino Observatory via the charged current (CC) reaction on deuterium and the elastic scattering (ES) of electrons. The flux of nu(e)'s is measured by the CC reaction rate to be straight phi(CC)(nu(e)) = 1.75 +/- 0.07(stat)(+0.12)(-0.11)(syst) +/- 0.05(theor) x 10(6) cm(-2) s(-1). Comparison of straight phi(CC)(nu(e)) to the Super-Kamiokande Collaboration's precision value of the flux inferred from the ES reaction yields a 3.3 sigma difference, assuming the systematic uncertainties are normally distributed, providing evidence of an active non- nu(e) component in the solar flux. The total flux of active 8B neutrinos is determined to be 5.44+/-0.99 x 10(6) cm(-2) s(-1).

Direct evidence for neutrino flavor transformation from neutral-current interactions in the Sudbury Neutrino Observatory.

Observations of neutral-current nu interactions on deuterium in the Sudbury Neutrino Observatory are reported. Using the neutral current (NC), elastic scattering, and charged current reactions and assuming the standard 8B shape, the nu(e) component of the 8B solar flux is phis(e) = 1.76(+0.05)(-0.05)(stat)(+0.09)(-0.09)(syst) x 10(6) cm(-2) s(-1) for a kinetic energy threshold of 5 MeV. The non-nu(e) component is phi(mu)(tau) = 3.41(+0.45)(-0.45)(stat)(+0.48)(-0.45)(syst) x 10(6) cm(-2) s(-1), 5.3sigma greater than zero, providing strong evidence for solar nu(e) flavor transformation. The total flux measured with the NC reaction is phi(NC) = 5.09(+0.44)(-0.43)(stat)(+0.46)(-0.43)(syst) x 10(6) cm(-2) s(-1), consistent with solar models.

Measurement of day and night neutrino energy spectra at SNO and constraints on neutrino mixing parameters.

The Sudbury Neutrino Observatory (SNO) has measured day and night solar neutrino energy spectra and rates. For charged current events, assuming an undistorted 8B spectrum, the night minus day rate is 14.0%+/-6.3%(+1.5%)(-1.4%) of the average rate. If the total flux of active neutrinos is additionally constrained to have no asymmetry, the nu(e) asymmetry is found to be 7.0%+/-4.9%(+1.3%)(-1.2%). A global solar neutrino analysis in terms of matter-enhanced oscillations of two active flavors strongly favors the large mixing angle solution.