Mean Airway Pressure (mean + airway_pressure)

Distribution by Scientific Domains
Distribution within Medical Sciences


Selected Abstracts


A comparison of the i-gelÔ with the LMA-UniqueÔ in non-paralysed anaesthetised adult patients

ANAESTHESIA, Issue 10 2009
H. Francksen
Summary This study assessed two disposable devices; the newly developed supraglottic airway device i-gelÔ and the LMA-UniqueÔ in routine clinical practice. Eighty patients (ASA 1,3) undergoing minor routine gynaecologic surgery were randomly allocated to have an i-gel (n = 40) or LMA-Unique (n = 40) inserted. Oxygen saturation, end-tidal carbon dioxide, tidal volume and peak airway pressure were recorded, as well as time of insertion, airway leak pressure, postoperative sore-throat, dysphonia and dysphagia for each device. Time of insertion was comparable with the i-gel and LMA-Unique. There was no failure in the i-gel group and one failure in the LMA-Unique group. Ventilation and oxygenation were similar between devices. Mean airway pressure was comparable with both devices, whereas airway leak pressure was significantly higher (p < 0.0001) in the i-gel group (mean 29 cmH2O, range 24,40) compared with the LMA-Unique group (mean 18 cmH2O, range 6,30). Fibreoptic score of the position of the devices was significantly better in the i-gel group. Post-operative sore-throat and dysphagia were comparable with both devices. Both devices appeared to be simple alternatives to secure the airway. Significantly higher airway leak pressure suggests that the i-gel may be advantageous in this respect. [source]


Nasal high-frequency ventilation for premature infants

ACTA PAEDIATRICA, Issue 11 2008
Tarah T Colaizy
Abstract Aim: To assess the use of nasal high-frequency ventilation (HFV) to provide noninvasive ventilatory support for very low birthweight (VLBW) infants. Study Design: VLBW infants, >7 days of age on nasal continuous positive airway pressure (CPAP), were placed on nasal HFV for 2 h using the Infant Star high-frequency ventilator (Mallinckrodt, Inc., St. Louis, MO, USA). Mean airway pressure was set to equal the previous level of CPAP, and amplitude was adjusted to obtain chest wall vibration. Capillary blood was sampled before starting HFV and after 2 h to determine change in pH and partial pressure of carbon dioxide (pCO2). Results: Fourteen subjects were studied, 10 males and 4 females. Gestational age was 26,30 weeks (median 27). Age at study was 18,147 days (median 30). Median birth weight was 955 g; median weight at study was 1605 g. Nasal CPAP pressure was 4,7 cm H2O (mean 5). Amplitude was 30,60 (median 50). After 2 h, PCO2 (mean 45 torr) was significantly lower than initial PCO2 (mean 50 torr) (p = 0.01), and pH had increased significantly (7.40 vs. 7.37, p = 0.04). Conclusions: Nasal HFV is effective in decreasing pCO2 in stable premature infants requiring nasal CPAP support. Long-term use of nasal HFV requires further study. [source]


Randomized trial comparing natural and synthetic surfactant: increased infection rate after natural surfactant?

ACTA PAEDIATRICA, Issue 5 2000
AK Kukkonen
The efficacy of a natural porcine surfactant and a synthetic surfactant were compared in a randomized trial. In three neonatal intensive care units, 228 neonates with respiratory distress and a ratio of arterial to alveolar partial pressure of oxygen <0.22 were randomly assigned to receive either Curosurf 100mgkg,1 or Exosurf Neonatal 5 ml kg,1. After Curosurf, the fraction of inspired oxygen was lower from 15min (0.45 ± 0.22 vs 0.70 ± 0.22, p = 0.0001) to 6 h (0.48 ± 0.26 vs 0.64 ± 0.23,p= 0.0001) and the mean airway pressure was lower at 1 h (8.3 3.2 mmH2O vs 9.4 ± 3.1 mmH2O ,= 0.01). Thereafter the respiratory parameters were similar. The duration of mechanical ventilation (median 6 vs 5 d) and the duration of oxygen supplementation (median 5 vs 4 d) were similar for Curosurf and Exosurf After Curosurf, C-reactive protein value over 40 mg r1 occurred in 45% (vs 12%; RR 3.62, 95%CI 2.12-6.17, p = 0.001), leukopenia in 52% (vs 28%; RR 1.85, 95%CI 1.31-2.61, ,= 0.001) and bacteraemia in 11% (vs 4%; RR3.17, 95%CI 1.05-9.52, p < 0.05). We conclude that when given as rescue therapy Curosurf had no advantage compared with Exosurf in addition to the more effective initial response. Curosurf may increase the risk of infection. [source]


Haemodynamic changes during positive-pressure ventilation in children

ACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 5 2005
A. Kardos
Background:, Positive-pressure ventilation may alter cardiac function. Our objective was to determine with the use of impedance cardiography (ICG) whether altering airway pressure modifies the central haemodynamics in mechanically ventilated children with no pulmonary pathology. Central venous saturation (ScvO2) was measured as an indicator of tissue perfusion. Methods:, Twelve children between 7 and 65 months of age, requiring mechanical ventilation as a consequence of a non-pulmonary disease, were enrolled in the study. All patients had a central venous line as a part of their routine management. Using pressure controlled ventilation (PCV) the baseline PEEP value of 5 cmH2O (Pb5) was increased to 10 cmH2O (Pi10) and then to 15 cmH2O (Pi15). After Pi15, PEEP was decreased to 10 (Pd10) and then to 5 cmH2O (Pd5). Each time period lasted 5 min heart rate (HR), mean arterial blood pressure (MABP), central venous pressure (CVP), end-tidal carbon dioxide (ETCO2), mean airway pressure (Paw), stroke volume index (SVI), cardiac index (CI) and central venous oxygen saturation (ScvO2) were recorded at the end of the five periods. Results:, The values of CI did not change when 10 and 15 cmH2O of PEEP were applied. Elevation of PEEP and thus Paw caused slight but not significant reductions in SVI and ScvO2 as compared to the baseline (Tb5). After reducing PEEP in Td5 we found statistically significant elevations of SVI and CI, as compared to Ti15 heart rate, ETCO2 and MABP remained unchanged. Conclusion:, We did not find significant haemodynamic changes following PEEP elevation in ventilated children, as measured using impedance cardiography. Reducing the value of PEEP to 5 cmH2O resulted in statistically significant SVI elevations. The values of ScvO2 remained unaffected. [source]


Ventilator treatment in the Nordic countries.

ACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 9 2002
A multicenter survey
Background: A 1-day point prevalence study was performed in the Nordic countries to identify ventilator-treatment strategies in the region. Material and methods: On 30 May 30 2001 all mechanically ventilated patients in 27 intensive care units (ICUs) were registered via the internet. The results are shown as medians (25th, 75th percentile). Results: ,One hundred and eight patients were included (69% male) with new simplified acute physiology score (SAPS) 48 (37,57) and 4.5 d (2,11) of ventilator treatment. The most frequent indication for ventilator treatment was acute respiratory failure (73%). Airway management was by endotracheal tube (64%), tracheostomy (32%) and facial mask (4%). Pressure regulated ventilator modes were used in 86% of the patients and spontaneous triggering was allowed in 75%. The tidal volume was 7 ml/kg (6,9), peak inspiratory pressure 22 cmH2O (18,26) and positive end-expiratory pressure (PEEP) 6 cmH2O (6,9). FiO2 was 40% (35,50), SaO2 97% (95,98), PaO2 11 kPa (10,13), PaCO2 5.4 kPa (4.7,6.3), pH 7.43 (7.38,7.47) and BE 2.0 mmol/l (, 0.5,5). The PaO2/FiO2 ratio was 220 mmHg (166,283). The peak inspiratory pressure (r=0.37), mean airway pressure (r=0.36), PEEP (r=0.33), tidal volume (r=0.22) and SAPS score (r=0.19) were identified as independent variables in relation to the PaO2/FiO2 ratio. Conclusion: The vast majority of patients were ventilated with pressure-regulated modes. Tidal volume was well below what has been considered conventional in recent large trials. Correlations between the parameters of gas exchange, respiratory mechanics, ventilator settings and physiological status of the patients was poor. It appears that blood gas values are the main tool used to steer ventilator treatment. These results may help to design future interventional studies of ventilator treatment. [source]


Natural surfactant combined with beclomethasone decreases oxidative lung injury in the preterm lamb

PEDIATRIC PULMONOLOGY, Issue 12 2009
Carlo Dani MD
Abstract We performed a randomized study in preterm lambs to assess the hypothesis that the treatment with natural surfactant combined with beclomethasone might decrease pulmonary oxidative stress in an animal model of respiratory distress syndrome (RDS). Animals received 200,mg/kg of porcine natural surfactant or 200,mg/kg of natural surfactant combined with 400 or 800,µg/kg of beclomethasone. Lung tissue oxidation was studied by measuring total hydroperoxide (TH), advanced oxidation protein products (AOPP), and non-protein bound iron (NPBI) in bronchial aspirate samples. In addition, lung mechanics was evaluated. TH was lower in the groups treated with surfactant plus 400 or 800,µg/kg of beclomethasone than in the surfactant group; AOPP was lower in the group treated with surfactant plus 800,µg/kg of beclomethasone than in the other groups; NPBI was similar in all groups. Surfactant treatment was followed by a sustained improvement of tidal volume (TV) and airway resistance, while dynamic compliance did not vary. However, the mean airway pressure needed to obtain similar values of TV was lower in the group treated with surfactant plus 800,µg/kg of beclomethasone than in other groups. We concluded that natural surfactant combined with beclomethasone at 800,µg/kg is effective in reducing the oxidative lung stress and improving the respiratory function in an animal model of RDS. Pediatr Pulmonol. 2009; 44:1159,1167. © 2009 Wiley-Liss, Inc. [source]


Nitric oxide inhalation therapy in very low-birthweight infants with hypoplastic lung due to oligohydramnios

PEDIATRICS INTERNATIONAL, Issue 1 2004
Naoki Uga
AbstractBackground: Although nitric oxide inhalation (iNO) therapy improves arterial oxygenation and reduces the rate of extracorporeal membrane oxygenation in term neonates, the efficacy of this therapy in premature infants is controversial. The objective of the present study was to determine whether iNO therapy improves the survival of very low-birthweight infants with pulmonary hypoplasia due to prolonged rupture of membrane. Methods: A retrospective comparative study of very low-birthweight infants with pulmonary hypoplasia due to oligohydramnios who had or had not been treated with iNO therapy, was performed (iNO-treated group, eight infants; control group, 10 infants). A neonate was considered to have pulmonary hypoplasia due to oligohydramnios if the following conditions were satisfied: (i) artificial surfactant treatment did not improve the respiratory distress; (ii) prolonged rupture of membrane (PROM) continued for more than 5 days with oligohydramnios; and (iii) sufficient arterial oxygenation did not occur even after giving 100% oxygen, and more than 8 cm H2O of mean airway pressure was needed to maintain arterial oxygenation. Results: Nitric oxide inhalation improved arterial oxygenation rapidly and consistently in all eight infants with pulmonary hypoplasia. All eight iNO-treated infants survived longer than 28 days, while five of the 10 control infants died within 24 h of birth (P < 0.05). Before starting iNO, seven of the eight treated infants had shown persistent pulmonary hypertension, which was confirmed by echocardiography. No iNO-treated infant had IVH greater than grade 1, while one control infant had grade 2 IVH. All six long-term survivors in the iNO-treated group are developing normally, while only two of the control infants are developing normally as of February 2002. Conclusions: The majority of the infants with pulmonary hypoplasia due to oligohydramnios had persistent pulmonary hypertension. iNO improved the arterial oxygenation and significantly improved the survival rate. A controlled study to determine whether iNO therapy improves the survival rate of preterm infants with pulmonary hypoplasia due to oligohydramnios is necessary. [source]


Performance of neonatal ventilators in volume targeted ventilation mode

ACTA PAEDIATRICA, Issue 2 2007
Atul Sharma
Abstract Aim: To test the hypothesis that in volume targeted ventilation modes, ventilator performance would vary according to ventilator type. Methods: Four neonatal ventilators: Draeger Babylog 8000 (Draeger Medical, Germany), SLE 5000 infant ventilator (SLE systems, UK), Stephanie paediatric ventilator (F. Stephan Biomedical, German) and V.I.P. Bird gold (Viasys Healthcare, USA) were assessed using a lung model. Delivered peak pressure, inflation time, mean airway pressure (MAP) and volume were measured. Results: At the same preset ventilator settings, the Stephanie and V.I.P. Bird ventilators delivered significantly lower peak pressures and tended to deliver lower MAPs than the other two ventilators. At a volume targeted ventilation level of 5 mL, the SLE and the V.I.P. Bird delivered significantly shorter inflation times. The above differences related to differences in the airway pressure waveforms delivered by the four ventilators. The V.I.P. Bird had a less variable volume delivery, but this was always significantly lower than the preset volume guarantee level but higher than the volume displayed by the ventilator. Conclusion: In volume targeted ventilation modes, performance differs between neonatal ventilator types; these results may have implications for clinical practise. [source]