The Effects Of Positive End-expiratory Pressure (PEEP) On Hemodynamics And Blood Gas In The Patients Undergoing Percutaneous Nephrolithotomy (PCNL)

Object: To explore the effects of positive end-expiratory pressure（PEEP）oncentral venous pressure, airway pressure and blood gas in the patientsundergoing percutaneous nephrolithotomy（PCNL）.Method: Sixty patients with upper urinary calculi, anesthesia ASAgrading I^II. Undergoing PCNL with ultrasonography （USG）-guided renalaccess and X-ray-guided，in the prone position under general anesthesia. Thesepatients were randomly assigned into2groups, group A （control group, n=30）PEEP0cmH2O, group B （PEEP group, n=30） PEEP5cmH2O. to ObservationNoninvasive blood pressure （BP）, mean arterial pressure （MAP）, heart rate （HR）,oxygen saturation （SpO₂）, central venous pressure （CVP）, airway pressure（Pmean）.After patients were prone position, for the recording time points: beforelithotripsy （T1）, started lithotripsy30min （T2），started lithotripsy60min （T3），finished lithotripsy （T4）,to record arterial blood gas values of pH （pH）, partialpressure of carbon dioxide （PaCO₂）, partial pressure of oxygen （PaO₂），baseexcess（BE）.Result: Compared with group A（PEEP0cmH₂O）,after group B was givenPEEP5cmH₂O, the level of CVP, Pmean and PaO₂of group B wassignificantly higher than that of group A （P<0.05）, MAP,HR,PH,PaCO₂, and BE between two groups were not different（P>0.05）.Compared withT1,following the promotion of operation,in T3^T4, the levels of PH、BE、PaO₂were lower than those of T1（P<0.05），CVP and Pmean of T2^T4weresignificantly higher than that of group B（P<0.05）. Compared with T1, in T3,the levels of serum potassium, serum sodium were higher than those of T1（P<0.05）.Conclusion: The patients undergoing PCNL in general anesthesia, withPEEP, PaO₂and arterial oxygenation can be improved effectively, airwaypressure and the level of CVP increase during the PCNL, the patientsundergoing Percutaneous nephrolithotripsy may suffer acid-base balance ofwater and electrolyte disorders, especially operation time is over60minutes. sothat anesthesiologists should strengthen the monitoring.