Backing and forthing: the process of decision making by women considering participation in a breast cancer prevention trial.

PURPOSE/OBJECTIVES: To describe the process of decision making by women considering participation in a breast cancer prevention trial (BCPT). DESIGN: Qualitative. SETTING/SAMPLE: Twenty-six women considering participation in a BCPT in the Northeastern United States. METHODS: Women were interviewed one or two times over a period of one year, with each interview averaging 40 minutes in length. The grounded theory method was used to collect and analyze the data. In-depth interviews were conducted with each participant. Data were analyzed using the constant comparative method. MAIN RESEARCH CONCEPTS: Context, decision making, meaning. FINDINGS: The core variable of backing and forthing is a nonlinear complex process of decision making that includes reviewing life, wanting to be sure, chancing and deciding within the contexts of fear, view of self in the world, transgenerational issues, and social support. CONCLUSIONS: The process of decision making for women considering participation in a BCPT is complex. Women tend to make decisions based on what is in their heads and hearts. They often are concerned more about others than they are about themselves. IMPLICATIONS FOR NURSING PRACTICE: Trust in the provider and active involvement in the process is critical to women making a decision to participate in a BCPT. Decision making is unique for each woman; however, understanding the context, the core variables, and the process will help healthcare providers to support decision making.

The relationship between the arteriovenous carbon dioxide gradient and cardiac index.

It has been reported that under normal conditions, mixed venous blood gases have approximated arterial samples; however, during cardiac arrest or severe cardiogenic shock, marked differences between arterial and venous blood gases have been noted. To further assess the relationships between arterial and mixed venous blood gases and cardiac index, a study population was chosen consisting of patients with less severe states of cardiac impairment. The differences between arterial and mixed venous PCO2s and pHs were compared with cardiac indexes (CI) of 44 patients in an intensive care unit with arterial lines and Swan-Ganz catheters in place. Twenty-six patients with normal CIs (2.6 to 4.1 L/min/m2) had a mean difference in mixed venous-arterial PCO2 (delta PCO2) of 4.88 +/- 0.40 mm Hg. In patients with low CIs (< 2.6), the delta PCO2 was 7.44 +/- 0.63 mm Hg (P = .001). The difference of mixed venous and arterial pH (delta pH) was 0.027 +/- 0.004 pH units for patients with normal CIs and 0.04 +/- 0.003 pH units for those with low CIs (P < .002). When the CIs of all patients were plotted against the delta PCO2s, there was an inverse linear relationship wherein delta PCO2 increased as CI decreased (r = -.47, P = .0011). There is an inverse relationship between delta PCO2 and CI that has not been previously described. An elevated delta PCO2 may be a marker of a low cardiac index.