A system of quality management in dialysis

Because of changes in legislation, dialysis may now be performed in all hospitals in The Netherlands, which could affect the quality of the therapy. Therefore a system of quality management in health care, and especially in dialysis, was developed. In this article the implementation and evaluation of such a system is described.     

Effect of ageing on insulin and insulin-glucose sensitivity tests in rats

Summary Insulin tolerance tests have shown old rats to respond to injection of the hormone by a sharp and lasting drop in blood sugar. The difference between these animals and young and adult ones lies in their inability to restore a normal blood glucose level. Glucose tolerance and insulin-glucose tolerance tests show that glucose uptake under the influence of the hormone is significantly reduced with age in absolute terms. However, the difference in glucose assimilation coefficient in the absence or presence of insulin (ΔK) is comparable in all age groups; thus senile rats were found to be as sensitive even to small doses of hormone as the adult ones, if basal levels are taken into account.     

Bedside measurement of changes in lung impedance to monitor alveolar ventilation in dependent and non-dependent parts by electrical impedance tomography during a positive end-expiratory pressure trial in mechanically ventilated intensive care unit patients

Introduction  

As it becomes clear that mechanical ventilation can exaggerate lung injury, individual titration of ventilator settings is of special interest. Electrical impedance tomography (EIT) has been proposed as a bedside, regional monitoring tool to guide these settings. In the present study we evaluate the use of ventilation distribution change maps (ΔfEIT maps) in intensive care unit (ICU) patients with or without lung disorders during a standardized decremental positive end-expiratory pressure (PEEP) trial.     

Comparing hemodynamic effects with three different measurement devices, of two methods of external leg compression versus passive leg raising in patients after cardiac surgery

External leg compression (ELC) may increase cardiac output (CO) in fluid-responsive patients like passive leg raising (PLR). We compared the hemodynamic effects of two methods of ELC and PLR measured by thermodilution (COtd), pressure curve analysis Modelflow? (COmf) and ultra-sound HemoSonic? (COhs), to evaluate the method with the greatest hemodynamic effect and the most accurate less invasive method to measure that effect. We compared hemodynamic effects of two different ELC methods (circular, A (n = 16), vs. wide, B (n = 13), bandages inflated to 30 cm H₂O for 15 min) with PLR prior to each ELC method, in 29 post-operative cardiac surgical patients. Hemodynamic responses were measured with COtd, COmf and COhs. PLR A increased COtd from 6.1 ± 1.7 to 6.3 ± 1.8 L·min^?1 (P = 0.016), and increased COhs from 4.9 ± 1.5 to 5.3 ± 1.6 L·min^?1 (P = 0.001), but did not increase COmf. ELC A increased COtd from 6.4 ± 1.8 to 6.7 ± 1.9 L·min^?1 (P = 0.001) and COmf from 6.9 ± 1.7 to 7.1 ± 1.8 L·min^?1 (P = 0.021), but did not increase COhs. ELC A increased COtd and COmf as in PLR A. PLR B increased COtd from 5.4 ± 1.3 to 5.8 ± 1.4 L·min^?1 (P < 0.001), and COhs from 5.0 ± 1.0 to 5.4 ± 1.0 L·min^?1 (P = 0.013), but not COmf. ELC B increased COtd from 5.2 ± 1.2 to 5.4 ± 1.1 L·min^?1 (P = 0.003), but less than during PLR B (P = 0.012), while COmf and COhs did not change. Bland–Altman and polar plots showed lower limits of agreement with changes in COtd for COmf than for COhs. The circular leg compression increases CO more than bandage compression, and is able to increase CO as in PLR. The less invasive Modelflow? can detect these changes reasonably well.     

Lung overinflation without positive end-expiratory pressure promotes bacteremia after experimental Klebsiella pneumoniae inoculation

Objective: To determine the effect of peak inspiratory pressure (PIP) and positive end-expiratory pressure (PEEP) on the development of bacteremia with Klebsiella pneumoniae after mechanical ventilation of intratracheally inoculated rats. Design: Prospective, randomized, animal study. Setting: Experimental intensive care unit of a University. Subjects: Eighty male Sprague Dawley rats. Interventions: Intratracheal inoculation with 100 μl of saline containing 3.5–5.0 × 10⁵ colony forming units (CFUs) K. pneumoniae/ml. Pressure-controlled ventilation (frequency 30 bpm; I/E ratio = 1 : 2; FIO₂ = 1.0) for 180 min at the following settings (PIP/PEEP in cmH₂O): 13/3 (n = 16); 13/0 (n = 16); 30/10 (n = 16) and 30/0 (n = 16), starting 22 h after inoculation. Arterial blood samples were obtained and cultured before and 180 min after mechanical ventilation and immediately before sacrifice in two groups of non-ventilated control animals (n = 8 per group). After sacrifice, the lungs were homogenized to determine the number of CFUs K. pneumoniae. Measurements and results: The number of CFUs recovered from the lungs was comparable in all experimental groups. After 180 min, 11 animals had positive blood cultures for K. pneumoniae in group 30/0, whereas only 2, 0 and 2 animals were positive in 13/3, 13/0 and 30/10, respectively (p < 0.05 group 30/0 versus all other groups). Conclusions: These data show that 3 h of mechanical ventilation with a PIP of 30 cmH₂O without PEEP in rats promotes bacteremia with K. pneumoniae. The use of 10 cmH₂O PEEP at such PIP reduces ventilation-induced K. pneumoniae bacteremia. Received: 17 September 1997 Accepted: 28 November 1997     

Mechanical ventilation with high positive end-expiratory pressure and small driving pressure amplitude is as effective as high-frequency oscillatory ventilation to preserve the function of exogenous surfactant in lung-lavaged rats

OBJECTIVE: To demonstrate that under well-defined conditions, pressure-controlled ventilators (PCV) allow settings that are as good as high-frequency oscillatory ventilators (HFOV) at preserving the function of exogenous surfactant in lung-lavaged rats. DESIGN: Experimental, comparative study. SETTING: Research laboratory of a large university. SUBJECTS: Sixteen adult male Sprague-Dawley rats (280-310 g). INTERVENTIONS: Lung injury was induced by repeated lavage. After last lavage, all animals received exogenous surfactant and were then randomly assigned to two groups (n = 8 per group). The first group received PCV with small pressure amplitudes and high positive end-expiratory pressure. The second group received HFOV. In both groups, an opening maneuver was performed by increasing airway pressure to improve PaO2/F(IO2) to > or =500 torr. MEASUREMENTS AND MAIN RESULTS: Blood gases were measured every 30 mins for 3 hrs. Airway pressures were measured with a tip catheter pressure transducer. At the end of the study period, a pressure-volume curve was recorded and a broncho-alveolar lavage was performed to determine protein content and surfactant composition. The results showed that arterial oxygenation in both groups could be kept >500 torr during the 3-hr study period by using a mean airway pressure of 13+/-3 cm H2O in PCV and 13+/-2 cm H2O in HFOV. Further, there were no differences in the Gruenwald index, protein influx, or ratio of small to large aggregates between the study groups. CONCLUSION: PCV with sufficient level of positive end-expiratory pressure and small driving pressure amplitudes is as effective as HFOV to maintain optimal gas exchange, to improve lung mechanics, and to prevent protein influx and conversion of large into small aggregates after exogenous surfactant therapy in lung-lavaged rats.     

Morphometric analysis of endocrine pancreas in old rats

The hypothesis of a degenerescence of Langerhans islets in senile animals has been tested by the morphometrical analysis of the pancreas of rats 6 and 24 months old. The method has allowed to show the presence in old animals of a higher number of islets per area unit; the distribution curve shows a shifting towards the larger sizes. If the surrounding connective tissue which thickens with age is not taken into account, the relative volumes occupied by the sinusoid capillaries and the A and B cells appear similar in the two age groups, as well as the nucleo-cytoplasmic ratio of these cells and the granulation of the cells secreting insulin. So, the morphological aspect of Langerhans islets does not reveal a decrease of the insulin stores in the pancreas of old rats.     

The effect of nitroglycerin on microvascular perfusion and oxygenation during gastric tube reconstruction

Esophagectomy followed by gastric tube reconstruction is the surgical treatment of choice for patients with esophageal cancer. Complications of the cervical anastomosis are associated with impaired microvascular blood flow (MBF) and ischemia in the gastric fundus. The aim of the present study was to differentiate whether the decrease in MBF is a result of arterial insufficiency or of venous congestion. To do this we assessed MBF, microvascular hemoglobin oxygen saturation (muHbSo(2)), and microvascular hemoglobin concentration (muHbcon) simultaneously during different stages of gastric tube reconstruction. In 14 patients, MBF was determined with laser Doppler flowmetry, and muHbSo(2) and muHbcon were determined with reflectance spectro- photometry. After completion of the anastomosis, nitroglycerin was applied at the fundus. Although MBF did not change significantly in the pylorus, MBF decreased progressively during surgery in the fundus from 210 +/- 18 Arbitrary Units at baseline (normal stomach) to 52 +/- 9 Arbitrary Units after completion of reconstruction (mean +/- sem; P < 0.05). There was no change in muHbSo(2) and muHbcon during the reconstruction. After application of nitroglycerin, MBF doubled. We conclude that MBF decreases during gastric tube reconstruction but that muHbSo(2) and muHbcon do not. This decrease might be the result of venous congestion, which can partly be counteracted by application of nitroglycerin.