Effects Of Different Respiratory Frequency On PaCO₂ And Hemodynamics During Hysterectomy With Laparoscopy

【objective】To investigate the effect of different respiratory frequency on PaCO2,BP,HR during the anesthesia for gynecological laparoscopic surgery, to search more appropriate and secure respiratory frequency for gynecology laparoscopic surgery, to avoid the hypocapnia and hypercapnia.[methods]Select 75 cases ASAⅠ-Ⅱ,weigh43-72kg,29-64 years old, all the patients were operated on hysterectomy under general anesthesia. They were divided into 5 groups randomly (group A, B,C,D,E), each group with 15 cases. Tidal volume was 8ml/kg of all the groups. After surgery the respiratory frequency of the 5 groups was12bpm/min,13 bpm/min,14 bpm/min,15 bpm/min,16 bpm/min in turn.30min before surgery intramuscular atropine 0.5 mg. Anesthesia induction period:intravenous midazolam 0.06mg/kg, fentanyl 3ug/kg, vecuronium 0.12mg/kg, etomidate 0.35mg/kg. Anesthesia maintenance period:intravenous vecuronium 0.04 mg/kg/20min, propofol 2ug/kg/min, remifentanil 0.15ug/kg/min, inhaled isoflurane2%.Record the SBP,HR,SPO2. PaCO2 at the time point before pneumoperitoneum(TO), after pneumoperitoneum 10 min (T1),15min(T2), 30min(T3).[results] (1) The change of SBP:group A, B compared with TO, the SBP obviously heightened at T1, T2 and T3 time points, there was significant difference (P<0.05). Group C compared with TO, SBP obviously heightened at T1,T2 time points, there was significant difference (P< 0.05), SBP approximate to TO at T3 time points, there was no significant difference(p>0.05); Group D, E compared with TO, SBP obviously heightened at T1 time point(P< 0.05), SBP approximate to TO at T2, T3 time points, there was no significant difference (P>0.05).(2) The change of HR:group A, B compared with TO, HR obviously increased at T1, T2 and T3 time point (P<0.05); group C compared with TO,HR significantly increased at T1, T2 time points (P<0.05),at T3 time point HR was no significant difference (P>0.05);Group D compared with TO, HR obviously increased at T1 time point, there was significant difference (P< 0.05), at T2, T3 time points, HR was mild increase, but there was no significant difference (P> 0.05);Group E compared with TO, HR obviously increased at T1 time point, there was significant difference (P< 0.05), atT2, T3 time points, down, HR was mild slow, there was no significant difference (P> 0.05).(3)The change of PaCO2:group A compared with TO, PaCO2 significantly increased at T1, T2 and T3 time points (P<0.05), and exceed the normal range (P<0.05); Group B compared with TO, PaCO2 was a little increased at T1, T2, time points(P> 0.05), PaCO2 significantly increased at T3 time point (P<0.05), but are all in normal range, there was no clinical significance; group C compared with TO, PaCO2 was mild increase at T1, T2 and T3 time points, there was no significant difference (P>0.05). Group D compared with TO, PaCO2 was mild decline at T1, T2 and T3 time points (P>0.05); Group E compared with TO, PaCO2 was mild decline at T1 time points, there was no significant difference, PaCO2 was obviously decline at T2, T3 time points, below normal,there was significant difference (P< 0.05).【conclusion】When the tidal volume was set 8ml/kg during gynecological laparoscopic surgery, the respiratory frequency should achieve 13 t-15 bpm/min.