Quality improvement: a new approach to quality assurance

The use of programs to help administrators and staff of health care facilities assess and monitor the quality of services provided is not new. For years, quality assurance (QA) programs have provided generalized sets of standards against which hospitals and other agencies measure their performance. Recently, there has been a trend towards quality improvement (QI) programs which advocate a more proactive response to quality concerns and emphasize a decentralized use of assessment and evaluation findings to continuously improve the care provided. QI is recognized as holding great opportunities for the enhancement of professional nursing practice and the improvement of patient care. In this paper, the process and design of QI was described and the advantages of this approach were recognized.     

Nutrition et fonction immunitaireNutrition and immune function

A deficiency of total energy or of one or more essential nutrients, including vitamins A, B₆, B₁₂, C, and E, folic acid, zinc, iron, copper, selenium, essential amino acids and essential fatty acids, will impair immune function and increase susceptibility of the host to infectious pathogens. This is most likely because these nutrients are involved in the molecular and cellular responses to challenge of the immune system. Providing these nutrients to deficient individuals restores immune function and improves resistance to infection. Thus, appropriate nutrition is required in order for the host to maintain adequate immune defences towards bacteria, viruses, fungi, parasites and tumour celîs. Although the intakes of several nutrients which result in greatest enhancement of immune function appear to be greater than recommended intakes, excess intake of certain nutrients also impairs immune responses. Some nutrients (e.g. glutamine, arginine) may become limiting in critical illness and there is mounting evidence that provision of these will aid patient recovery.     

INVOLVEMENT OF NON-NMDA AND NMDA RECEPTORS IN GLUTAMATE-INDUCED PRESSOR OR DEPRESSOR RESPONSES OF THE PONS AND MEDULLA

1. Fifty-five intact and six baroreceptor denervated and vagotomized cats of either sex were anaesthetized intraperito-neally with urethane (400 mg/kg) and a-chloralose (40 mg/kg). Responses of the systemic arterial pressure (SAP), mean SAP (MSAP) and sympathetic vertebral nerve (VNA) and renal nerve activities (RNA) were recorded. 2. In intact animals, monosodium L-glutamate (Glu, 0.1 mol/L, 50 nL) was microinjected into pressor areas of the locus coeruleus (LC), gigantocellular tegmental field (GTF), rostral ventrolateral medulla (RVLM) and dorsomedial medulla (DM), and the depressor areas of caudal ventrolateral medulla (CVLM). The induced actions were compared before and after microinjection of either glutamate antagonists, glutamate diethylester (GDEE, 0.5 mol/L, 50–100nL), a competitive AMPA receptor blocker, or 2-amino-5-phosphonovaleric acid (D-AP5, 0.025 mol/L, 50–100 nL), a competitive N-methyl-D-aspartate (NMDA) receptor blocker. GDEE completely blocked the increases of SAP and VNA elicited from all pressor areas. D-AP5 only partially blocked the pressor but slightly blocked VNA and RNA responses from LC, GTF and DM, particularly those from RVLM. Neither GDEE nor D-AP5 blocked the depressor responses of SAP and two nerve activities elicited from CVLM. 3. In baroreceptor denervated animals, NMDA (2 mmol/L, 50–100 nL) and AMPA (0.2 mmol/L, 50–100 nL) were micro-injected into the same pressor areas of GTF, RVLM and DM and the depressor area of CVLM responsive to Glu activation (0.1 mol/L, 30 nL). In RVLM, DM and CVLM, the results of either NMDA or AMPA were similar to those induced by Glu. However, in GTF, microinjection of either NMDA or AMPA did not induce similar responses to Glu. This suggests that the nature of GTF may differ from RVLM and DM. 4. The above results suggest that the Glu-induced pressor responses from LC, GTF, DM and especially RVLM, are primarily mediated through AMPA receptors. The Glu-induced depressor responses from CVLM may not be predominantly mediated by either AMPA or NMDA receptors. 5. In both baroreceptor-intact and -denervated cats stimulation of the pressor areas often produced an increase of VNA and a decrease of RNA, while in the depressor CVLM decreased both VNA and RNA. The VNA, but not RNA were positively correlated with the pressor responses, while both VNA and RNA were positively correlated with the depressor responses. This may suggest that neurons of the sympathetic vertebral and renal nerves are topographically organized in the brain.