Utility of intra-operative capnogram to detect branch pulmonary artery obstruction following total correction of tetralogy of fallot.

Branch pulmonary artery obstruction is one of the prime reasons for re-operation in patients who have undergone repair for tetralogy of Fallot. Branch pulmonary artery obstruction may develop over a period of time due to dilation of right ventricular outflow tract or it may be caused by residual stenosis after inadequate repair. This may lead to differential lung perfusion causing morbidity. Intra-operative capnogram monitoring reveals ventilation−perfusion relationship. We report two cases where the capnogram helped the diagnosis and management of branch pulmonary artery obstruction. We found a redundant patch in the first and an extra length of the homograft in second case which led to the obstruction. However, but for the changes in the intraoperative capnogram, this condition may by far remain undiagnosed considering the fact that it does not produce hemodynamic changes but can lead to postoperative morbidity.

Broken inspiratory valve detected by capnographic waveforms during general anesthesia: A case report / 대한마취과학회지

Unidirectional valve malfunction causes re-breathing of expired gas during anesthesia. Capnography is a useful method for monitoring the integrity of anesthetic equipment such as the unidirectional valves in a circular system. We report, here a case in which the capnography did not sound any rebreathing alarm, but the capnogram showed a prolonged plateau, an apparently short inspiratory period and a gradually sloping descending limb that stopped just short of baseline. As a result, capnography helped to identify an inspiratory unidirectional valve malfunction during the course of anesthesia. This study emphasizes the need to analyze the capnogram during every procedure involving anesthesia, in addition to preoperative checking of the Unidirectional valve.

Does the " Curare Cleft " on the Capnogram always mean that the Patient is in Need of Relaxant ? / 대한마취과학회지

A fifty-eight years old male patient was given general anesthesia for the clipping of aneurysm on the posterior communicating artery. The respiration of the patient was controlled with Ohmeda 7000 anesthesia ventilator. During the surgery there appeared curare cleft on the capnogram which did not disappear after the administration of neuromuscular blocker, but disappeared after the change of the anesthesia ventilator with another one. After that another curare cleft was made by the transient obstruction of the outlet of the excess patient circuit gas of the new anesthesia ventilator. It may be said that inappropriately functioning pop-off valve of the anesthesia ventilator can be one of the causes of curare cleft on the capnogram.