Eleni Kostadima

Clarithromycin reduces the severity of bronchial hyperresponsiveness in patients with asthma

A randomised double-blind placebo-controlled study was designed to evaluate the effects of a semisynthetic macrolide antibiotic, clarithromycin, on bronchial hyperresponsiveness to methacholine in patients with a diagnosis of asthma. Adult asthma patients undergoing treatment with budesonide 400 µg b.i.d. and salbutamol 200 µg p.r.n. less than twice weekly were studied. Arm A (16 males/six females, aged 48±16 yrs) received clarithromycin 250 mg b.i.d. for 8 weeks, arm B (eight males/12 females, aged 42±12 yrs) clarithromycin 250 mg t.i.d. and arm C (six males/15 females, aged 41±16 yrs) placebo dextrose tablets. Bronchial hyperresponsiveness was quantified by measurement of the provocative dose of methacholine causing a 20% fall in forced expiratory volume in one second (PD20). Median (interquartile range) PD20 in the three groups before and after treatment with clarithromycin were: arm A: 0.3 (0.1–1) and 1.3 (0.6–2) mg; arm B: 0.4 (0.1–0.9) and 2 (2–2) mg; and arm C: 0.4 (0.1–0.9) and 0.3 (0.1–0.6) mg, respectively. Serum free cortisol levels were determined and remained unchanged from baseline in the clarithromycin-treated patients. It is concluded that clarithromycin reduces the degree of bronchial hyperresponsiveness in patients with asthma.

Early gastrostomy reduces the rate of ventilator-associated pneumonia in stroke or head injury patients.

Presence of a nasogastric tube is a risk factor for the development of ventilator-associated pneumonia (VAP). Alternatively, gastrostomy can be used for administration of enteral feedings. To determine whether early performance of gastrostomy affects frequency of VAP, a randomised, controlled study was carried out in patients mechanically ventilated for stroke or head injury. In the gastrostomy group, patients underwent the procedure within 24 h of intubation. A nasogastric tube was inserted in controls. Individual subjects were studied for 3 weeks. In total, 20 subjects (mean age 48±15.2 yrs) were allocated to the gastrostomy group, and 21 to the control group (46.6±15.4 yrs). Of these groups, two (10%) and eight (38.1%) developed VAP, respectively. Four patients with gastrostomy and three controls did not complete the study (due to weaning from ventilatory support or death). After excluding these subjects, difference in VAP frequency persisted: two out of 16 subjects with gastrostomy had VAP (12.5%) versus eight out of 18 controls (44.4%). There were no differences in duration of hospitalisation or mortality between the two groups. In conclusion, in patients mechanically ventilated for stroke or head injury early gastrostomy is associated with a lower frequency of ventilator-associated pneumonia compared with a nasogastric tube.

Venous Oxygen Saturation And Lactate Gradient From Superior Vena Cava To Pulmonary Artery In Patients With Septic Shock

Monitoring of central venous oxygen saturation (ScvO2) is considered comparable with mixed venous oxygen saturation (SvO2) in the initial resuscitation phase of septic shock. Our aim was to assess their agreement in septic shock in the intensive care unit setting and the effect of a potential difference in a computed parameter, namely, oxygen consumption (VO2). In addition, we sought for a central venous to pulmonary artery (PA) lactate gradient. We enrolled 37 patients with septic shock who were receiving noradrenaline infusions, and their attending physicians had placed a PA catheter for fluid management. Blood samples were drawn in succession from the superior vena cava, right atrium (RA), right ventricle, and PA. Hemodynamic and treatment parameters were monitored, and data were compared by correlation and Bland-Altman analysis. Mixed venous oxygen saturation was lower than ScvO2 (70.2% ± 11.4% vs. 78.6% ± 10.2%; P < 0.001), with a bias of −8.45% and 95% limits of agreement ranging from −20.23% to 3.33%. This difference correlated significantly to the noradrenaline infusion rate and the oxygen consumption and extraction ratio. These lower SvO2 values resulted in computed VO2v higher than the VO2cv (P < 0.001), with a bias of 104.97 mL min−1 and 95% limits of agreement from −4.12 to 214.07 mL min−1. Finally, lactate concentration was higher in the superior vena cava and RA than in the PA (2.42 ± 3.15 and 2.35 ± 3.16 vs. 2.17 ± 3.19 mM; P < 0.01 for both comparisons). Thus, our data suggest that ScvO2 and SvO2 are not equivalent in intensive care unit patients with septic shock. Additionally, the substitution of ScvO2 for SvO2 in the calculation of VO2 produces unacceptably large errors. Finally, the decrease in lactate between RA and PA may support the hypothesis that the mixing of RA and coronary sinus blood is at least partially responsible for the difference between ScvO2 and SvO2.

Morning levels of fibrinogen in children with sleep-disordered breathing

Elevated fibrinogen level is a predictor of cardiovascular disease in adults, and it is associated with sleep-disordered breathing. Levels of fibrinogen in adults are affected by other co-existing cardiovascular risk factors, which are not usually present in children. To investigate the association between fibrinogen and sleep-disordered breathing, a case-control study was carried out in children with and without habitual snoring. All snoring children underwent polysomnography. Morning fibrinogen values in 30 children with snoring and an apnoea-hypopnoea index (AHI) ≥5 episodes·h−1 (median (interquartile range) 318 mg·dL−1 (290–374)) were similar to values in 61 children with snoring and an AHI <5 episodes·h−1 (307 (269–346)). Both groups had higher fibrinogen values than those in 23 controls without snoring (271 mg·dL−1 (244–294)). There was no correlation between fibrinogen values and AHI, respiratory movement/arousal index or haemoglobin desaturation index. In conclusion, fibrinogen values are higher in children with snoring than in controls, but there is no association between these values and polysomnography indices.

Cardiac systolic function in Greek children with obstructive sleep-disordered breathing

BACKGROUND Obstructive sleep-disordered breathing (SDB) in children has been associated with increased ventricular strain and decreased left ventricle (LV) diastolic function. The aim of this study was to assess systolic myocardial function in children with SDB of variable severity. METHODS Children who were referred for polysomnography during the study period underwent echocardiography (two-dimensional, Doppler and tissue Doppler imaging). RESULTS A total of 46 subjects (age 6.4+/-2.6years) were recruited. Fourteen of them had moderate-to-severe SDB (obstructive apnea-hypopnea index (OAHI): 16.6+/-11.6 episodes/h), 13 children had mild SDB (OAHI: 3.1+/-0.7 episodes/h) and 19 subjects had primary snoring (OAHI: 1.2+/-0.6 episodes/h). Children with moderate-to-severe SDB had significantly lower LV shortening fraction (SF) and ejection fraction (EF) than subjects with primary snoring (p<0.05). SF in moderate-to-severe SDB, mild SDB and primary snoring groups was: 34.3+/-5.5%, 36.9+/-3.2% and 37.7+/-4.4%, respectively, and EF: 66.9+/-7.9%, 71.7+/-6.4% and 72.3+/-5.9%, respectively. OAHI, age, and systolic blood pressure were significant predictors of SF and EF (p<0.01). CONCLUSIONS In children with obstructive SDB, LV systolic function is inversely associated with severity of intermittent upper airway obstruction during sleep.

Correlation of urinary excretion of sodium with severity of sleep-disordered breathing in children: A preliminary study†

Nocturnal urinary sodium excretion is related to blood pressure (BP) levels. Elevated BP and increased nocturnal natriuresis have been demonstrated in adults with sleep apnea. Although evidence indicates increased BP in children with obstructive sleep‐disordered breathing (SDB), it is unknown whether these children have also enhanced urinary sodium excretion.