Conflict associated with decisions to limit life-sustaining treatment in intensive care units.

OBJECTIVE: To determine the incidence and nature of interpersonal conflicts that arise when patients in the intensive care unit are considered for limitation of life-sustaining treatment. DESIGN: Qualitative analysis of prospectively gathered interviews. SETTING: Six intensive care units at a university medical center. PARTICIPANTS: Four hundred six physicians and nurses who were involved in the care of 102 patients for whom withdrawal or withholding of treatment was considered. MEASUREMENTS: Semistructured interviews addressed disagreements during life-sustaining treatment decision making. Two raters coded transcripts of the audiotaped interviews. MAIN RESULTS: At least 1 health care provider in 78% of the cases described a situation coded as conflict. Conflict occurred between the staff and family members in 48% of the cases, among staff members in 48%, and among family members in 24%. In 63% of the cases, conflict arose over the decision about life-sustaining treatment itself. In 45% of the cases, conflict occurred over other tasks such as communication and pain control. Social issues caused conflict in 19% of the cases. CONCLUSIONS: Conflict is more prevalent in the setting of intensive care decision making than has previously been demonstrated. While conflict over the treatment decision itself is most common, conflict over other issues, including social issues, is also significant. By identifying conflict and by recognizing that the treatment decision may not be the only conflict present, or even the main one, clinicians may address conflict more constructively.

Families looking back: one year after discussion of withdrawal or withholding of life-sustaining support.

OBJECTIVE: To identify critical psychosocial supports and areas of conflict for families of intensive care unit (ICU) patients during decisions to withdraw or withhold life-sustaining treatment. DESIGN: Cross-sectional survey. SETTING: Six intensive care units in a tertiary care academic medical center. PARTICIPANTS: Forty-eight family members, one per case, of patients previously hospitalized in the ICU who had been considered for withdrawal or withholding of life-sustaining treatment. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Two raters coded transcripts of audiotaped interviews with family members about their experiences in the ICU and the decision-making process for withdrawing or withholding life-sustaining treatment. Codes identified sources of conflict and personal, institutional, and staff supports on which families relied during the decision-making process. Forty-six percent of respondents perceived conflict during their family member's ICU stay; the vast majority of conflicts were between themselves and the medical staff and involved communication or perceived unprofessional behavior (such as disregarding the primary caregiver in treatment discussions). Sixty-three percent of family members previously had spoken with the patient about his or her end-of-life treatment preferences, which helped to lessen the burden of the treatment decision. Forty-eight percent of family members reported the reassuring presence of clergy, and 27% commented on the need for improved physical space to have family discussion and conferences with physicians. Forty-eight percent of family members singled out their attending physician as the preferred source of information and reassurance. CONCLUSIONS: Many families perceived conflict during end-of-life treatment discussions in the ICU. Conflicts centered on communication and behavior of staff. Families identified pastoral care and prior discussion of treatment preferences as sources of psychosocial support during these discussions. Families sought comfort in the identification and contact of a "doctor-in-charge." ICU policies such as family conference rooms and lenient visitation accommodate families during end-of-life decision-making.

Peptide YY inhibits vasopressin-stimulated chloride secretion in inner medullary collecting duct cells.

mIMCD-k2 cells are derived from the inner medullary collecting duct of a mouse and exhibit electrogenic sodium absorption and cAMP- and vasopressin (AVP)-stimulated electrogenic chloride secretion [N. L. Kizer, B. Lewis, and B. A. Stanton. Am. J. Physiol. 268 (Renal Fluid Electrolyte Physiol. 37): F347-F355, 1995; and N. L. Kizer, D. Vandorpe, B. Lewis, B. Bunting, J. Russell, and B. A. Stanton. Am. J. Physiol. 268 (Renal Fluid Electrolyte Physiol. 37): F854-F861, 1995]. The purpose of the present study was to determine how peptide YY (PYY) affects electrogenic Na+ and Cl- current in mIMCD-k2 cells. Short-circuit currents (Isc) were measured across monolayers of mIMCD-k2 cells mounted in Ussing-type chambers. PYY did not alter baseline Isc, nor did it alter Isc in chloride-free conditions, indicating no effect on electrogenic sodium transport. Baseline chloride current in these cells is low; therefore, chloride short-circuit current (IClsc) was stimulated with AVP (10 nM) added to the basolateral surface and 10 microM amiloride added to the apical surface. Although apical applications of PYY had no effect, basolateral application of PYY caused attenuation of IClsc, with the maximal inhibitory dose (100 nM) causing 52 +/- 1.3% inhibition (IC50 = 0.11 nM). Inhibition by PYY of IClsc is mediated through the Y2 receptor subtype, as PYY-(3-36) was the only PYY analog tested that caused inhibition and was equipotent to PYY. Inhibition by PYY of IClsc was abolished following incubation with pertussis toxin. We also show that PYY inhibits AVP-stimulated cAMP accumulation, with a maximal inhibitory dose (100 nM) causing a 38% +/- 6% inhibition (IC50 = 0.16 nM), comparable to inhibition by PYY of IClsc. We conclude that PYY acts through either Gi or Go to inhibit adenylate cyclase activity, leading to a decrease in AVP-stimulated chloride current.

Effects of epiphyton onPotamogeton crispus L. leaves.

Potamogeton crispus L. grows as a winter producing annual in the shallow lakes of the Pongolo Floodplain, South Africa. Colonization of leaves by algal and bacterial epiphytes, as seen by scanning electron microscopy, followed the established pattern of increasing diversity and density with leaf age. It was apparent from the micrographs that the primary and subsequent colonizers were present even after death of the host leaf. Cross sections of leaves, viewed by transmission electron microscopy, illustrated that bacterial attachment did not damage the surface of young leaves. There was, however, extensive inward swelling and disorganization of the epidermal walls, characteristic of a reaction to invasion by pathogens. In older leaves the swelling was also present in mesophyll cells, while bacteria had invaded and degraded the epidermal cell wall. The bacterial invasion was concomitant with signs of senescence, and in dead leaves the organisms had penetrated and degraded the epidermis and mesophyll cell walls. The epiphyton/ host relationship may therefore be considered necrotrophic with important consequences for the transfer of energy from producers to consumers during decomposition.