Holistic care of the critically ill: meeting both patient and family needs.

Holistic care of the critically ill includes meeting the needs of both the patient and the patient's family. The critical care nurse needs to be prepared to deal with the family's special needs during a time of crisis, including making decisions about the withdrawal of life support. This article addresses such issues, and includes care of the family once technological support has been withdrawn and the patient is transferred from the Intensive Care Unit.

The experience of dyspnea during weaning.

OBJECTIVE: To compare the degree of dyspnea experienced by ventilator-dependent patients receiving synchronized intermittent mandatory ventilation (SIMV) versus T-piece or pressure support ventilation (PSV) weaning. The relationship between self-reported perceptions of dyspnea and physiologic variables observed during weaning trials was examined. Variables included heart rate, respiratory rate, minute ventilation, and oxygen saturation as measured by a pulse oximeter. DESIGN: Quasi-experimental, counterbalanced design with repeated measures. SETTING: Medical intensive care unit of a large university-affiliated medical center. PATIENTS: Nine mechanically ventilated patients diagnosed with chronic obstructive lung disease. The patients were admitted for respiratory failure between May 1990 to November 1990. Six tolerated SIMV 4 versus T-piece trials; three were placed in the SIMV 8 versus PSV trials. PROCEDURE: Each patient's perception of dyspnea was measured using a visual analog scale (VAS) at the initiation and at 5-minute intervals of 20-minute weaning trials. Physiologic indicators were noted simultaneously with VAS ratings of dyspnea. RESULTS: Findings indicated no difference in the degree of dyspnea experienced between weaning methods compared. Within-subject regression analysis on VAS scores revealed individual differences in the relationship between physiologic indicators and perceptions of dyspnea. CONCLUSIONS: The patient's experience of dyspnea during the weaning process can be a valuable guide to observe the patient's progress. The VAS serves as a reliable, easy-to-use tool for quantifying the patient's perception of dyspnea.

Evidence for humoral immunodepression in NO2-exposed mice: influence of food restriction and stress.

The effects of food restriction or 20 ppm NO2 exposure on humoral immunity were investigated in normal and adrenalectomized C57Bl/6 mice. The thymic and splenic weights of sham-operated mice were similarly diminished after 4 days of NO2 exposure or 4 days of food depletion. The responses of corresponding adrenalectomized mice were less depressed. Undernutrition induced lymphoid organ involution and corticosteroids were partly involved. Plaque-forming cells (PFC) per spleen and per 10(6) cells were markedly depressed after 4 days of NO2 exposure, but less so after food deprivation. The same significant suppression of PFC was observed in adrenalectomized groups. Depression of humoral immunity was independent of stress-induced endogenous steroids. Moreover, NO2 had a specific effect on humoral immunodepression, food restriction being an associated factor.

Impaired acquired resistance of mice to Klebsiella pneumoniae infection induced by acute NO2 exposure.

The natural resistance of nonimmunized C57Bl/6 mice to an intraperitoneal Klebsiella pneumoniae challenge was not significantly affected by prior continuous exposure to 20 ppm NO2 for 4 days. In contrast, the acquired resistance of mice immunized just before and infected just after NO2 exposure was seriously impaired. This could not be explained by the loss of appetite (about 30%) observed in NO2 treated mice, for neither the natural nor acquired resistance of control air exposed mice given approximately 70% ad libitum food and water were significantly modified.

[Effect of inhalation of hair spray on the rat respiratory system]. / Effet de l'inhalation de laque capillaire sur l'appareil respiratoire du rat.

A study of the effects of inhaled hair-spray was performed on 118 specific pathogen free male Wistar rats (71 test animals and 47 controls). Rats were exposed for 5 min, three times a day, five days per week, during one to eight weeks, in two plexiglas chambers, one for controls and one for test animals. The chambers were 20 1 in size, but only the noses of the animals were exposed to ambiant air or to a hair-spray aerosol polluted atmosphere. In the test chamber, the hair-spray was aerosolized for 30 s at the beginning of each exposure, using about 30 g of nebulized product. This hair-spray amount was high, although non-lethal (70% of DL0, 45% of DL50 and 26% of DL100). The hair-spray exposed rats exhibited significant modifications in the antixenic defence mechanisms of their respiratory system: diminished ciliary activity of the tracheal epithelium (-26%), increased number of harvested pulmonary macrophages (+52%), but decreased phagocytic ability of these cells (-8%). However we did not observe histologic differences in the respiratory system of exposed and control rats.

Sex-related factors in acute carbon monoxide intoxication in one strain of mice.

In the OF1 mouse strain, males are less resistant than females to acute carbon monoxide intoxication. Castration of males increases their resistance to carbon monoxide. For Neonates injected with four different doses of testosterone (20-500 mg per kg) or oestradiol (2-50 mg per kg), more effect on resistance to carbon monoxide in the (adult) mice was found for oestradiol than for testosterone. Pregnancy decreases resistance to carbon monoxide intoxication. Experiments performed with males and females of different ages, in various societal conditions, show the effects of sex-related dimorphism and aggressiveness. The sex-related difference in carbon monoxide resistance is not modified by a previous hypoxic stress (nitrogen hypoxia, carbon monoxide intoxication, sodium cyanide injection) but is suppressed when the CO intoxication is carried out at a low ambient temperature (13 degrees C).

Natural and acquired resistance of mice to infection by airborne Klebsiella pneumoniae after subchronic intoxication by cadmium administered orally.

Mice daily ingested about 22 mg of cadmium per kg of body weight in drinking water for 30 days. On the 30th day, the liver and kidneys of the mice contained about 18 micrograms of Cd2+ per g of fresh organ. A group of these mice was immunized against Klebsiella pneumoniae using two injections of vaccine, the first on the 7th day and the second on the 14th day of intoxication. On the 28th day, the non-immunized and the immunized mice were infected via a respiratory route by one lethal dose 50% of K. pneumoniae (the LD50 for the immunized mice was 2.4 times higher than the LD50 for the non-immunized mice). Comparison with the non-intoxicated control mice showed that the ingestion of Cd2+ did not significantly modify the natural resistance or the acquired resistance of the mice to the infection by airborne K. pneumoniae.

Sex-related factors in acute hypoxia survival in one strain of mice.

In mice of different ages from the OF1 mouse strain, males are less resistant than females to a normobaric hypoxia obtained in a few hours by a progressive lowering of normoxic PO2 with nitrogen flushing. Injection of estradiol to castrated males and spayed females increases hypoxic survival. Neonates which have been injected with a high dose of estradiol show, when adult, a high hypoxic resistance. In adult females, hypoxic survival is lower during diestrus than during estrus. Pregnancy decreases resistance to hypoxia. Experiments, performed with males and females of different ages, show the effects of sex-related dimorphism and aggressiveness. Hypoxias at various ambient temperatures demonstrate that the sex difference in hypoxic survival persists in spite of variations in rectal temperatures.

Influence of inhaled cadmium microparticles on mouse influenza pneumonia.

A study of the effect of inhaled cadmium microparticles (CdO) on the mouse death rate from influenza pneumonia was performed on 936 female specific pathogen-free (SPF) Swiss mice. The test animals received a single short (15 min) exposure to 9 mg Cd/m3 of air (acute exposure), or renewed short exposures to 1 mg/m3 once a day, 5 days a week, for 4 weeks (chronic exposure). The cadmium found in the trachea-bronchus-lung area was about 5 micrograms/g of fresh tissue at the end of acute exposure, and 4 micrograms/g at the end of chronic exposure. The viral challenge was performed 48 hr after acute exposure, or on the 14th day after the beginning of chronic exposure, the mice being reexposed to Cd for an additional 14 days in the latter case. Surprisingly, the infectious death rate of test mice was significantly lower than that of controls, both for acute and chronic exposure to CdO. These results are discussed.

Opposite effects of inhaled cadmium microparticles on mouse susceptibility to an airborne bacterial and an airborne viral infection.

An experimental study on 489 mice is reported. The test animals were submitted to a single 15-mn exposure to atmosphere containing about 10 mg of cadmium microparticles (CdO) per m3 of air and the controls to an equivalent amount of aluminium microparticles (Al2o3). At the 48th hour after exposures, the test and control mice were submitted to a bacterial (Pasteurella multocida) or to a viral (Orthomyxovirus influenzae A) challenge, via the respiratory route. The exposure to cadmium significantly increased the death-rate of mice submitted to the bacterial challenge, but it significantly decreased the death-rate following the viral challenge.

[In vitro and in vivo effect of cadmium microparticles on antibody receptors of alveolar macrophage membranes]. / Effet du cadmium microparticulaire, in vitro et in vivo, sur les récepteurs membranaires d'anticorps des macrophages alvéolaires.

Microparticles of cadmium oxide inhibited antibody-mediated rosette formation by Rat alveolar macrophages. After 4 h of contact in vitro, the 50% inhibiting amount of the pollutant, expressed as metal-Cd, was about 6,000 ng per million cells. 48 h after exposure via the respiratory route, 3,000 hg of Cd per gram of rat fresh lung lowered the percentage of rosette-forming macrophages by about 25%.

[Effect of pyrolysis products of polypropylene plastic on the defence mechanisms of the respiratory system (author's transl)]. / Effet du pyrolysat de matière plastique polypropylénique sur les mécanismes de défense de l'appareil respiratoire.

Since the use of plastic materials, a change in the pathology of fire victims has been observed. We studied the effects of a single short-term inhalation (30 min) of a sub-lethal dose of polypropylene pyrolysis products (one LD-0). Including control and test animals, 66 rats and 112 mice were used. The exposure provoked disturbances in the antixenic defense mechanisms of the respiratory system, chiefly in tracheo-bronchial defenses, since we observed a lowering of ciliary activity of 35 to 78% in test animals exposed a few hours before, compared with the controls. These changes provoked a significant increase in death-rate of test animals, following experimental airborne infection by Klebsiella pneumoniae. The combustion products of polypropylene plastic materials did not contain hydrocyanic acid nor hydrochloric acid, and neither the temperature of the inhaled air, nor the concentration of carbon monoxide could explain these effects. On the contrary, we can suspect the well known irritative properties of aldehyde compounds formed during smoldering combustion of polypropylene.

Effects of nitric oxide on resistance to bacterial infection in mice.

Continuous exposure to 2 ppm nitric oxide (NO) for as long as 4 wk did not reduce the resistance of male mice to infection by aerosol inoculation with Pasteurella multocida. In contrast, mortality was slightly enhanced and survival shortened in NO-exposed compared to control female mice; however, the importance of these small differences is uncertain. These results suggest only that male and female mice did not react similarly to the infectious challenge after exposure to NO.

An improved device for frequency recording of tracheal ciliary beat.

An improved device for frequency recording of cyclic movements on the cellular level is described. The device consists of a modified conventional microscope lit by a laser source, an analyzer comprising a fiber optic transmission system, a photodector, an amplifier, a recorder and a thermostatic equipment, including a thermoprobe. In vitro experiments are reported concerning variation in activity as a function of temperature, with respect to the frequency of ciliary beat in rat ring trachea.

Effects of lead microparticles on the growth characteristics of the BHK21 fibroblast cell line.

BHK21 fibroblastic cells were exposed in vitro to lead microparticles produced by pyrolysis of the organic lead used as an antiknock agent in gasoline. Although non-cytolethal, 10 micrograms of lead/10(6) cells rapidly inhibited cell growth kinetics as well as [3H]thymidine and L-[3H]leucine incorporation by the BHK21 cell line. The growth rate inhibition provoked by chronic exposure to lead microparticles became reversible when the cells were cultured without the microparticulate pollutant. The cloning efficiency of BHK21 cells was impaired by lead concentrations above 1 mg/10(6) cells.

In vitro cytotoxicity of cadmium microparticles for rabbit pulmonary alveolar macrophages.

A cytotoxic effect of cadmium monoxide microparticles on rabbit pulmonary alveolar macrophages was observed in vitro from 1 to 2 microg of metal cadmium per million cells (and per milliliter of incubation medium). This threshold was close to the one observed with lead microparticles, which in addition appeared to have a faster cytotoxic action. On the other hand, cadmium microparticles inhaled in vivo are known to be much more toxic to the respiratory system and much more slowly cleared from it than lead particles. These contradictions can be partially explained by our observation that in vitro the ability of alveolar macrophages to phagocytize microparticles was significantly lower for cadmium monoxide than for lead monoxide microparticles.