title: [The effect of positive pressure ventilation combined with diaphragm pacing on respiratory mechanics in patients with respiratory failure].
abstract: OBJECTIVE
  To observe the effects of combining positive pressure ventilation with diaphragm pacing on respiratory mechanics in patients with respiratory failure.
  
  
  METHODS
  Twenty patients with central respiratory failure were studied with cohorts. The effects on respiratory mechanics were respectively observed in patients in control group, in whom ventilation by positive pressure only, and patients in experimental group in whom ventilation was instituted by combining positive pressure ventilation with diaphragm pacing.
  
  
  RESULTS
  Compared with control group, mean airway pressure (Paw, cm H(2)O, 1 cm H(2)O= 0.098 kPa) and plateau pressure (Pplat, cm H(2)O) were significantly decreased in experimental group (Paw: 6.1±1.3 vs. 7.3±1.8; Pplat: 10.4±2.5 vs. 12.1±2.6, both P<0.05), while the negative value of peak esophageal pressure (P(PEAK ES) , cm H(2)O), the negative value of the difference between peak and basic esophageal pressure (dP(ES), cm H(2)O), transpulmonary pressure at end of inspiration hold (Ptp plat, cm H(2)O ), static compliance (Cst, ml/cm H(2)O) were significantly increased in experimental group (P(PEAK ES): -8.3± 1.9 vs. -3.2±1.4; dP(ES) : -11.2±2.6 vs. -8.2±2.2; Ptp plat: 23.6±3.8 vs. 15.6±3.1; Cst: 52.7±8.2 vs. 48.3±7.2, all P<0.05). No differences were found in airway resistance (Raw, cm H(2)O×L(-1) ×s(-1) ) and lung resistance (R(L), cm H(2)O×L(-1) ×s(-1) ) between experimental group and control group (Raw: 2.1±0.5 vs. 2.3±0.4; R(L): 2.9±0.6 vs. 3.1±0.5, both P>0.05). Work of breath by patient (WOBp, J/L) was significantly increased and work of breath by ventilator (WOBv, J/L) was significantly decreased in experimental group compared with control group (WOBp: 0.18±0.03 vs. 0; WOBv: 0.31±0.07 vs. 0.53±0.11, both P<0.05).
  
  
  CONCLUSIONS
  Compared with positive pressure ventilation , positive pressure ventilation combined with diaphragm pacing can decrease the Paw, increase intrathoracic negative pressure, transpulmonary pressure, and Cst, and decrease WOBv, while there is no effect on Raw and R(L).
authors.affiliation: Intensive Care Unit, the First People's Hospital of Yancheng, Yancheng 224001, Jiangsu, China. dengyj2003@163.com
authors.forename: Yi-Jun
authors.initials: YJ
authors.lastname: Deng
authors.forename: You-Lin
authors.initials: YL
authors.lastname: Ji
authors.forename: Lan-Ping
authors.initials: LP
authors.lastname: Chen
authors.forename: Qin
authors.initials: Q
authors.lastname: Jin
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000403:Airway Resistance; D003964:Diaphragm; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011175:Positive-Pressure Respiration; D012131:Respiratory Insufficiency / Q000503:physiopathology* / Q000628:therapy*; D055815:Young Adult