Clinical Investion Of Respiration's Pattern In The Stage Of General Anesthetic Recovery

PURPOSE: To approach a safe method of general anesthesia recovery, we engage in the research about the effects from intermittent positive pressure ventilation (IPPV), synchronous intermittent mandatory ventilation (SIMV), and biphasic positive airway pressure (BIPAP) on the recovering time of autonomous breathing and ventilation function, thus discuss the advantage and clinical value of SIMV and BIPAP used in general anesthesia recovery period.METHODS: Random sample 30 ASA Ⅰ—Ⅱ cases, and divide them into three groups: group I IPPV, group II SIMV, and group HI BIPAP. Each group has 10 cases. After the quick venous cannulation, a ventilator is connected to the patients to control the ventilation .At this moment, three groups share the same way of ventilation 桰PPV, then connect with nerve stimulator and neuromuscular transmission monitor, the pattern is train of four(TOF). Exam the blood gas before anaesthetizing and one hour after operation and before pulling the endotracheal intubation. Give the muscle relaxant for the last time before the end of operations. After that, adjust the way of ventilation of group II, group III to SIMV and BIPAP, take notes at the moments when the operations begin, when the blood gas is examined for the second time, and when the last muscle relaxant is given. Then at point TI, T4, TR=0.25, TR=0.75, there appear the Ppeak, Pmean, MV, EtCO2, BP, HR and the period of time between the last giving of muscle relaxant and pulling out endotracheal intubation. RESULT: l.When Tl appears, Ppeak, Pmean of the BIPAP group lower than those of the IPPV group and SIMV (p<0.01); When TR=0.75,Ppeak and Pmean of IPPV group lower than those of theSIMV and BIPAP group; 2.When Tireappears, the VE of BIPAP is higher than the IPPV group's (p<0.05), but isn't different from the SIMV group's(p>0.05); 3.When T4 reappears, TR=0.25, TR=0.75, the EtCC>2 of the SIMV group and BIPAP group are lower than the IPPV group's, but there is no other different markers; 4.During the analysis of the blood gas, the artery PCO2 of the SIMV and BIPAP group are lower than the IPPV group's.(p<0.05). There is no other different markers(p>0.05); 5. There is no other obvious different pulse rate, systolic and diastolic pressure at the three points(p>0.05); 6. The period between the last giving of vecuronium and autonomous breathing recovery, not the pulling out of the endotracheal intubation, is shorter in SIMV and BIPAP group than it in IPPV group (p<0.05). CONCLUSION: When three groups share the same ventilating way桰PPV, there is no obvious different markers and blood gas number in the three groups. However the differences appear as the patients recover their autonomous breathing and adjust the breathing way. Compare SIMV and BIPAP with IPPV, SIMV and BIPAP have the following advantages: no confrontation between mechanical ventilation and autonomous breathing; quick recovery of autonomous breathing; little change of airway pressure; high VE; low EtCo2, thus make patients have a smooth anesthesia recovery period. So SIMV and BIPAP are more suitable for anesthesia recovery. More than that, BIPAP can lower the airway's peak pressure and decrease the probability of barotraumon , therefore it's more suitable for those patients with high airway pressure.