Navigating systems ideas for health practice: Towards a common learning device

Systems thinking and reference to complexity science have gained currency in health sector practice and research. The extent to which such ideas might represent a mere passing fad or might more usefully be mobilized to tackle wicked problems in health systems is a concern underpinning this paper. Developing the usefulness of the systems idea requires appreciating how systems ideas are used essentially as constructs conceptually bounded by practitioners. Systems are used for purposes of understanding and engaging the reality of health issues, with the intent of transforming the reality into one that is more manageable, equitable, and sustainable. We examine some manifestations of the systems idea in health practice and the traditions of systems practice that variously make use of them. This provides a platform for proposing a systems thinking in (health) practice heuristic: a learning device supporting how different tools and methods can address “wicked problems” in health praxis. The device is built on the use of “conversation” as a metaphor to help practitioners use systems ideas in tandem with existing disciplinary and professional skills and methods. We consider how the application of the heuristic requires, and helps to develop, human characteristics of humility, empathy, and recognition of fallibility.     

Safety of reassessment-and-release practice for mental health patients boarded in the emergency department

Objectives

Among emergency department (ED) mental health and substance abuse (MHSA) patients, we sought to compare mortality and healthcare utilization by ED discharge disposition and inpatient bed request status.

Arterial oxygenation associated with portopulmonary hypertension

STUDY OBJECTIVES: To characterize arterial oxygenation in patients referred to Mayo Clinic for liver transplantation with a diagnosis of portopulmonary hypertension (portoPH). DESIGN: Prospective study. SETTING: Liver transplantation program and pulmonary hypertension clinic in a tertiary referral center. PARTICIPANTS: Twenty consecutive patients with abnormal pulmonary hemodynamics documented by right-heart catheterization (mean pulmonary artery pressure [MPAP] > or = 25 mm Hg, pulmonary vascular resistance [PVR] > or = 120 dyne.s.cm(-5), and pulmonary capillary wedge pressure [PCWP] < or = 15 mm Hg). Liver transplant candidates with normal pulmonary hemodynamics via screening Doppler echocardiography (n = 40) served as control subjects. A subgroup of patients underwent postural and inspired 100% oxygen blood gas analysis, contrast echocardiography, and technetium-labeled macroaggregated albumin ((99m)TcMAA) lung/brain scanning to identify and quantitate the degree of intracardiac or intrapulmonary shunting. MEASUREMENTS AND RESULTS: portoPH was moderate to severe (MPAP > 35 mm Hg) in 18 of 20 patients (90%). Arterial-alveolar oxygen pressure gradient (P[A-a]O(2)) was abnormal (> or = 20 mm Hg) in 16 of 20 patients (80%). PaO(2) was abnormal (< or = 70 mm Hg) in 3 of 20 patients (15%). Pa0(2) was significantly less and P(A-a)O(2) was significantly greater compared to control subjects (p < 0.001). All patients had normal (99m)TcMAA brain uptake (< 6%) and negative transthoracic contrast echocardiographic findings. No significant correlations were found between oxygenation and hemodynamic variables (MPAP, PVR, PVR index, and transpulmonary gradient). CONCLUSIONS: Arterial oxygenation associated with portoPH was frequently abnormal and significantly worse when compared to patients with normal pulmonary hemodynamics by Doppler echocardiography. Hypoxemia, as measured by PaO(2) and P(A-a)O(2), was usually mild even in the setting of moderate-to-severe portoPH.     

The dorsal premammillary nucleus: an unusual component of the mammillary body.

The results of anterograde and retrograde axonal transport experiments in the rat indicate that the dorsal premammillary nucleus (PMd) gives rise to a branched pathway ending in the anterior thalamic group and brainstem, like the medial and lateral mammillary nuclei. However, unlike these nuclei, the ascending PMd projection courses through and to the anterior hypothalamic nucleus, and the descending PMd projection ends in the periaqueductal gray, superior colliculus, and adjacent parts of the reticular formation. Also unlike the traditional mammillary nuclei, the PMd does not receive a direct input from the columns of the fornix; instead, it receives a bilateral input from the anterior hypothalamic nucleus, which in turn receives inputs from areas related to the prefrontal cortex, amygdala, and hippocampus. The results provide interesting perspectives on the organization of medial hypothalamic circuits underlying the goal-oriented behaviors associated with hunger, thirst, and reproduction.     

The relationship of adrenal iodomethylnorcholesterol uptake to indices of adrenal cortical function in Cushing's syndrome

The adrenal gland uptake of 131I-6-beta-iodomethyl-19-norcholesterol (NP-59) was calculated using a semioperator-independent computer algorithm in 17 patients with Cushing's syndrome (CS). Twelve had ACTH-dependent and 5 had ACTH-independent CS. The mean adrenal gland uptake (percentage of administered dose) of NP-59 was 0.74 +/- 0.18% (range, 0.21-2.02%) in CS and was significantly higher than that of normal subjects (0.33 +/- 0.02%). Patients with the ectopic ACTH syndrome and ACTH-independent CS manifested the highest uptakes (mean, 1.18 +/- 0.08%; range, 0.74-2.02%). In the patients with ACTH-dependent CS, a significant correlation was observed between 24-h urinary free cortisol excretion and NP-59 adrenal gland uptake (r = 0.97, P less than 0.001). No relationship was seen between NP-59 uptake and urinary free cortisol in ACTH-independent CS or between NP-59 uptake and urinary 17-hydroxycorticosteroids, 17-ketosteroids, cortisol secretion rate, plasma cortisol, or ACTH levels in either ACTH-dependent or ACTH-independent CS. We conclude that in addition to localizing the sites(s) of adrenocortical hypersecretion in CS, the level of NP-59 adrenal uptake is a reflection of cortisol excretion in ACTH-dependent disease and may be utilized as another parameter to quantitate adrenal disease activity in CS.     

Serum high density lipoprotein cholesterol correlates with presence but not severity of coronary artery disease

An elevated serum level of low density lipoprotein (LDL) is a risk factor for the development of coronary artery disease, whereas elevated levels of high density lipoprotein (HDL) appear to have a protective effect, and the total cholesterol to HDL ratio has been suggested as an improved method for assessing risk. We determined cholesterol, HDL and triglycerides in 189 patients undergoing diagnostic cardiac catheterization to determine if these variables correlate with the severity of coronary artery disease assessed as the number of major coronary vessels having ≥ 70 percent stenosis. HDL was higher in the group with zero vessel disease (54 ± 2.3 mg/dl ± SEM) than in those with one, two or three vessel disease (43 ± 1.8, 45 ± 1.8 and 51 ± 1.2, respectively), and the cholesterol to HDL ratio was lower in the group with zero vessel disease (4.1 ± 0.2 compared to 6.1 ± 0.3, 5.7 ± 0.2 and 6.4 ± 0.3 in the groups with 1, 2 and 3 vessel disease).Using analysis of variance, patients with no coronary artery disease (zero vessel disease) differed from those with coronary artery disease in HDL (p < 0.005), triglycerides (p > 0.01), cholesterol (p < 0.005) and cholesterol to HDL (p > 0.005), but no significant differences were found between patients with coronary artery disease and a different number of vessels involved. There were no significant differences between the groups in age, and although the group with zero vessel disease had more females than the others, there were no differences in cholesterol, HDL, cholesterol to HDL ratio, or triglycerides between male and female patients with no coronary artery disease. We conclude that the cholesterol to HDL ratio correlates with the presence but not severity of coronary artery disease.