Ventilatory Parameters and Inflammatory Responses of Neonates Ventilated by Different Modes of Ventilation

• IL-1beta levels in tracheal aspirate material [ Time Frame: Baseline and 72 hours of mechanical ventilation ] [ Designated as safety issue: No ]
  Tracheal aspirate will be analyzed for the mediator level and change from baseline will be reported
  
  
• IL-6 level in tracheal aspirate [ Time Frame: Baseline and 72 hours of mechanical ventilation ] [ Designated as safety issue: No ]
  Tracheal aspirate will be analyzed for IL6 level and the change from baseline will be reported
  
  
• IL-8 in tracheal aspirate material [ Time Frame: Baseline and 72 hours of mechanical ventilation ] [ Designated as safety issue: No ]
  Tracheal aspirate will be analyzed for the mediator level and change from baseline will be reported
  
  
• IL-10 level in tracheal aspirate material [ Time Frame: Baseline and 72 hours of mechanical ventilation ] [ Designated as safety issue: No ]
  Tracheal aspirate will be analyzed for the mediator level and change from baseline will be reported
  
  
• TNF alfa in tracheal aspirate material [ Time Frame: Baseline and 72 hours of mechanical ventilation ] [ Designated as safety issue: No ]
  Tracheal aspirate will be analyzed for the mediator level and change from baseline will be reported
  
  
• tidal volume variability [ Time Frame: 72 hours of mechanical ventilation or entire ventilation time if extubated earlier ] [ Designated as safety issue: Yes ]
  variability in tidal volume measured with babyview program
  
  
• peak inspiratory pressure variability [ Time Frame: 72 hours of mechanical ventilation or entire ventilation time if extubated earlier ] [ Designated as safety issue: Yes ]
  variability in peak inspiratory pressure measured with babyview program
  
  
• respiratory rate variability [ Time Frame: 72 hours of mechanical ventilation or entire ventilation time if extubated earlier ] [ Designated as safety issue: Yes ]
  changes in respiratory rate, tacypnea rate
  
  
• oxygen saturation variability [ Time Frame: 72 hours of mechanical ventilation or entire ventilation time if extubated earlier ] [ Designated as safety issue: Yes ]
  changes in oxygen saturation, desaturation rate, hyperoxy rate
  
  
• lowest carbondioxide level (mmHg) [ Time Frame: 72 hours of mechanical ventilation or entire ventilation time if extubated earlier ] [ Designated as safety issue: Yes ]
  ratio of hypocarbic blood gases and least pCo2 level
  
  
• highest carbondioxide level (mmHg) [ Time Frame: 72 hours of mechanical ventilation or entire ventilation time if extubated earlier ] [ Designated as safety issue: Yes ]
  ratio of hypercarbic blood gases and highest pCo2 level
  
  
• lowest oxygen level (mmHg) [ Time Frame: 72 hours of mechanical ventilation or entire ventilation time if extubated earlier ] [ Designated as safety issue: Yes ]
  ratio of hypoxic blood gases and least pO2 level
  
  
• highest oxygen level (mmHg) [ Time Frame: 72 hours of mechanical ventilation or entire ventilation time if extubated earlier ] [ Designated as safety issue: Yes ]
  ratio of hyperoxic blood gases and highest pO2 level
  
  

• bronchopulmonary dysplasia [ Time Frame: 36 weeks corrected age ] [ Designated as safety issue: Yes ]
  Oxygen requirement at 36 weeks corrected age
  
  
• patent ductus arteriosus [ Time Frame: in the first week of post natal life of the patient ] [ Designated as safety issue: No ]
  Presence of hemodynamically significant patent ductus arteriosus in the first 7 days of life
  
  
• necrotizing enterocolitis [ Time Frame: 36 weeks corrected age ] [ Designated as safety issue: No ]
  Necrotising entercolitis defined by clinical and radiological findings
  
  
• intraventricular hemorrhage [ Time Frame: during first week ] [ Designated as safety issue: Yes ]
  Intraventricular hemorrhage diagnosed by head ultrasound
  
  
• pneumothorax [ Time Frame: during first 3 days ] [ Designated as safety issue: Yes ]
  Air leak diagnosed by chest x-ray
  
  
• pulmonary interstitial emphysema [ Time Frame: during first week ] [ Designated as safety issue: Yes ]
  Air leak diagnosed by x-ray
  
  
• pulmonary hemorrhage [ Time Frame: during first week ] [ Designated as safety issue: Yes ]
  
• retinopathy of prematurity [ Time Frame: until 36 weeks corrected age ] [ Designated as safety issue: No ]
  Retinal disease diagnosed by indirect opthtalmoscopic exam
  
  

Term or preterm neonates may need mechanical ventilation due to different etiologies. In all patients aim of mechanical ventilation is to promote pulmonary gas exchange, reduce the respiratory work of patient. Ideal mechanical ventilation must minimize pulmonary trauma with low inspiratory pressures that obtains adequate and constant tidal volumes. Ventilation associated pulmonary injury is an important subject that must be considered during mechanical ventilation. Atelectotrauma, volutrauma, barotrauma and biotrauma must be monitored. Volutrauma, barotrauma and oxygen toxicity cause cytokine increase that results in biotrauma. This parenchymal inflammation is a risk factor for chronic lung disease which is an important morbidity of ventilated neonates.

From past to present neonates were ventilated with different ventilation modes including IMV (Intermittent Mandatory Ventilation), SIMV, A/C (Assist Control Ventilation), PSV,HFV (High Frequency Ventilation). Both PSV and SIMV are patient trigger ventilation modes but SIMV is a time cycled and PSV is a flow cycled mode. In recent years hybrid techniques were developed to combine beneficial features of volume and pressure limited ventilation. In commercial ventilation devices these techniques have different names as volume guaranteed pressure limited ventilation (Drager Babylog 8000), pressure regulated volume controlled ventilation (Siemens servo 3000), volume guaranteed pressure support ventilation (VIP Bird Gold).

Since there is not a standard protocol for mechanical ventilation of neonates different countries and even different NICU's use different ventilation protocols.

Literature supports volume targetted ventilation to reduce barotrauma with low maximum inspiratory pressures and to reduce volutrauma with constant tidal volumes. When A/C+VG and SIMV+VG were compared in a crossover trial, more constant tidal volumes were obtained in A/C mode. Inflammatory cytokines have also been measured in different groups of patients with variable ventilatory management techniques. So far there has not been a randomized study published comparing VG+SIMV with VG+PSV in newborns with regards to tidal volume , peak inspiratory pressure variability,or inflammatory cytokines. Therefore in this study the investigators aimed to compare these two ventilation modes with regards to short term outcome.