ETCare: a randomized, controlled, masked trial comparing two solutions for upper airway care in the NICU.

BACKGROUND: Small quantities of normal saline are sometimes instilled into the endotracheal tube of intubated neonates, to assist with the removal of thick secretions and maintain patency of the endotracheal tube. However, saline is detrimental to the innate immune system of the upper airway mucosa, rapidly unfolding and inactivating antimicrobial peptides such as LL-37. We previously reported the preparation and feasibility testing of 'ETCare', a low-sodium, physiologically based solution for airway care, and we now report results of a randomized, masked, controlled, two-centered study testing ETCare vs sterile saline among 60 intubated NICU patients. STUDY DESIGN: Sixty intubated NICU patients were randomized to having their airway care with ETCare vs saline. Three hypotheses were tested: (1) tolerance - patients will tolerate ETCare for airway care as well as they tolerate saline, (2) nosocomial infections - ETCare will result in fewer tracheal aspirates where organisms grow and fewer cases of nosocomial sepsis, and (3) chronic lung disuse - ETCare will result in fewer patients discharged home on supplemental O2. RESULTS: Thirty NICU patients with an endotracheal tube in place were randomized to receive their airway care with ETCare, and 30 to receive their care with saline. Only the pharmacist was aware of the randomization; the two solutions were visually indistinguishable and were dispensed in identical syringes. Tolerance of the solutions was similar. The ETCare recipients had trends toward fewer positive blood cultures (odds ratios (OR), 0.48; 95% confidence interval (CI), 0.13 to 1.68), and fewer discharges home on supplemental O2 (OR, 0.43; 95% CI, 0.14 to 1.32; P=0.075). CONCLUSIONS: On the basis of this study and our previous 10-patient feasibility trial, we maintain that, for airway care, intubated NICU patients tolerate ETCare as well as saline. Data from this study can be used in estimating the sample sizes needed for a phase III trial. We speculate that such a trial will demonstrate that, compared with saline, ETCare will result in fewer nosocomial infections and less chronic lung disease.

A qualitative analysis of the 'management of schizophrenia' within a medium-secure service for men with learning disabilities.

Within secure psychiatric services, nurses trained to work with people with learning disabilities are often called upon to deal with those experiencing psychosis; a role that they are not routinely prepared for in generic learning disability nurse training. Psycho-social interventions (PSI) are recommended as an adjunct to routine pharmacological treatment for people experiencing psychosis. There is a small literature that suggests that PSI has utility with people with learning disabilities. As part of a wider evaluation of the introduction of a PSI framework to a 10-bedded medium-secure unit for men with learning disabilities and mental health problems, 13 members of nursing staff completed the 'Management of Schizophrenic Patients Checklist'. The responses were analysed using a grounded theory approach. Principle themes identified are described. The therapy vs. security quandary frequently reported in forensic psychiatry was evident in responses. The findings are guiding a programme of training and ongoing supervision within the service and are discussed in the context of wider therapeutic issues and institutional environment.

Comparative assessment of chemical and gamma-irradiation procedures for implantable glucose enzyme electrodes.

Chemical and gamma-irradiation sterilisation were examined in this study for implantable needle electrodes. Exposure to isopropyl alcohol (IPA) led to response elevation, but time-dependent exposures up to 30 min variously to chlorhexidine, H2O2, HCl, HCl/IPA, and alcoholic iodine/potassium iodide, all caused substantial time-dependent response degradation. Sterility was not assessed for such electrodes. High dose (30 KGy) gamma-irradiation also compromised sensor response, with exposed electrodes exhibiting approximately 30% reduction in response, comparable in magnitude to 10 min exposure to chemical sterilisation. However, a lower dose (25 KGy) gamma-irradiation was well tolerated and subsequent microbiological testing (following contamination with Streptococcus epidermidis and Staphylococus aureus) proved device sterility with no culture growth following 7 days incubation at 37 degrees C in brain heart infusion medium.

Stabilized needle electrode system for in vivo glucose monitoring based on open flow microperfusion.

Preliminary in vitro studies and in vivo performance of amperometric glucose needle enzyme electrodes incorporating an open microflow technique, in which the sensor surface in subjected to a flow of fluid, are reported. Initially using a slow flow (60 microliters h-1) of isotonic phosphate buffer over the enzyme electrode tip, an interface was created which reduced cellular/protein fouling for electrode measurements in whole blood. Here a minor reduction in electrode response (apparent only at high glucose concentration) occurred which was not cumulative and therefore not associated with fouling. The protection afforded by the moving aqueous film was independent of fluid composition; the use of isotonic/hypertonic buffer, addition of anticoagulant (1% m/v heparin) or enhanced fluid viscosity (addition of 1% v/v glycerol) did not affect the system. Implantation of the electrode and its microflow cannula into subcutaneous tissue in rats was associated with a decreased buffer flow (30 microliters h(-1)) and had the effect of (i) reducing electrode stabilization (30 min), (ii) accelerating 'pick up' of tissue glucose changes after intravenous glucose (1-2 min lag) or insulin (3-7 min lag) and (iii) achieving a correlation between tissue and blood glucose values under dynamic conditions (r2 = 0.98, y = 0.99x + 0.23). Reassessment of the electrode response in vitro, following a 4 h monitoring period, provided a sensor response within 3% of the original electrode sensitivity, indicating little or no surface fouling and avoiding the requirement for repeated in vivo calibrations at least over the initial implantation period.

Open flow microperfusion: approach to in vivo glucose monitoring.

A slow flow of liquid over the working tip of a classical glucose needle electrode allows a significant reduction in surface fouling with minimal sample dilution. The fluid flow technique enables relatively drift-free in vivo operation for up to four hours (electrode responses in vitro following explanation of the device after a 4 h monitoring period are within +/- 5% of original values), exhibits a close correlation with blood glucose levels and is unique in requiring no in vivo calibration.

Shoulder subluxation in hemiplegia: effects of three different supports.

Shoulder subluxation in hemiplegia is a difficult problem to manage and it may be associated with pain and other complications. Measurements taken from x-rays have been used to obtain objective measures of shoulder subluxation, but have not been used to compare the effects of different shoulder supports. This study used x-ray measurements to evaluate different shoulder supports for subluxation in hemiplegia and to see if there was a significant difference between the Harris hemisling and the Bobath sling. The Harris hemisling gave good vertical correction of subluxation and compared closely to the uninvolved shoulder. The Bobath sling did not correct the subluxation as well, and the mean difference between the two slings was significant. The arm trough or lap board was less effective and tended to overcorrect. The Harris hemisling and arm trough or lap board had horizontal measurements similar to the uninvolved shoulders. The Bobath sling, however, distracted the glenohumeral joint horizontally and was more variable. The mean horizontal difference between the Harris hemisling and the Bobath sling was significant. These results support the effectiveness and specificity of shoulder support to decrease subluxation after hemiplegia.

Do angiotensin-induced changes in sheep renal venous blood and plasma composition indicate a reversal of glomerular filtration?

Angiotensin II markedly lowers the relative cell content of renal venous blood both with injection into the jugular vein and into the left ventricle of anaesthetised sheep; angiotensin I has a similar effect in this regard when given intravenously but the decreased cellular fraction is much less evident with left ventricular injection when the direct presentation to the kidneys precludes prior intra-pulmonary conversion to angiotensin II. The angiotensins also produce readily demonstrable alterations in renal venous plasma electrolyte, protein, creatinine and urea levels. This pattern of changes is related to associated intra-renal haemodynamics, reverse filtration of proximal tubular fluid, a possible anti-diuretic action of angiotensin I itself on the peritubular capillaries and acute renal failure in man and experimental animals.

Influence of angiotensin II on the concentration of arterial plasma electrolytes in anaesthetized sheep.

Angiotensin II and I significantly raised potassium and lowered sodium and chloride ion concentrations in arterial plasma, with peak changes occurring in the first 2 min of a 6-min infusion period. The octapeptide increased the arterial K+ level in a dose-dependent manner, but the response showed tachyphylaxis when multiple infusions of 6-min duration were administered after a recovery interval of only 5 min. Raising the arterial blood pressure by 20-33 mmHg with adrenaline and noradrenaline failed to account for the increase in arterial plasma K+ concentration produced by the two peptides. These findings, in particular the rise in K+ concentration, are discussed in relation to possible mechanisms by which angiotensin II affects arteriolar tone.

Propantheline bromide plasma level, urinary excretion and pharmacological data in a comparison of the bioavailability of three oral formulations of Pro-Banthine.

To determine the comparative bioavailability of three oral formulations of propantheline bromide (PB) by both pharmacokinetic and pharmacodynamic parameters, six normal men received three standard Pro-Banthine 15 mg tablets, two prolonged acting (PA) Pro-Banthine 30 mg tablets or one developmental PA Pro-Banthine 45 mg capsule, in a study of balanced random crossover design. Plasma concentrations and urinary excretion of the unchanged drug were measured after each treatment using a stable isotope dilution assay. Salivary secretion rate and heart rate measurements were also made at intervals after each medication. The standard Pro-Banthine formulation was significantly more bioavailable, weight for weight, than either the developmental PA capsule (45 mg), p less than 0.05, or the two 30 mg PA tablets (60 mg), p less than 0.01, based on urinary excretion and plasma levels of PB and on salivary secretion and heart rate data. There was no evidence of significant prolonged action for the PA formulations.

Diuretic induced hypokalaemia: relationship to dosage interval and plasma aldosterone.

Plasma potassium and aldosterone responses to 9 days treatment with hydrochlorothiazide (100 mg/day) alone or in combination with spironolactone (100 mg/day), prescribed once daily or in doses 12 h apart, were examined in a double-blind, crossover study in twelve healthy subjects. Plasma potassium concentrations were lower when the drugs were administered 12 h apart (P less than 0.01). Spironolactone attenuated significantly hydrochlorothiazide induced hypokalaemia--mean rise in plasma potassium, 0.36 mmol/l (P less than 0.001). The increase in plasma aldosterone was greater following combination therapies (P less than 0.001), but there were no significant differences between once daily and twice daily regimens. We conclude that plasma potassium concentration is better maintained when diuretics are given once daily and that this is not related closely to differences in plasma aldosterone responses.

Radioimmunoassay of unprocessed sheep blood extracts to follow angiotensin metabolism.

The acceptability of radioimmunoassay to determine the levels of compounds antigenic to anti-angiotensin antibodies, in unprocessed methanolic blood extracts, was established for sheep blood. This approach was used to follow the clearance of antigenic compounds after administration of angiotensins I and II and fragments of angiotensin II in anesthetized sheep. The organs supplied by the systemic circulation and also the lungs effectively removed angiotensin I, but the removal of octapeptide occurred only in the peripheral tissues. The blood concentrations of compounds reacting with the anti-angiotensin II antibody always increased with passage of angiotensin I through the pulmonary circulation but not with passage of angiotensin II. The results indicate that factors other than efficiency of removal by the tissue is important in establishing blood levels. The sites of administration and of sampling were shown to be important in relation to ratios of the concentrations of antigenic material. There was a similar uptake of both hormones in the kidney; the relative inability of angiotensin I to reduce renal blood flow, therefore, does not result from a failure of uptake.