A 40 years old chronic smoker was scheduled for cholecystectomy under general anesthesia. He was induced with propofol and vecuronium and started on isoflurane for maintenance of anesthesia. During the procedure, the following capnograph plot was observed. What is the possible cause?
B. Entry into right-sided bronchu
C. Leak from expiratory Valve
Ans: C. Leak from expiratory Valve
(Ref Miller 7/e p1427; Hemodynamic Monitoring. Lvolviii leclin)iogies and Clinical Practice By Mary E. Lough/p240).
Biphasic pattern of capnograph:
- Usually seen in cases of leak from expiratory valve adding to CO2 output.
- Mainly in chronic smoker with emphysema.
- Due to hyper expanded lung.
- In single lung transplantation patients.