Obstruction Due to Retained Carbon Dioxide Absorber Canister Wrapping

Water Accumulation in Amsorb Canister May Cause Inspiratory Flow Obstruction: A Case Report

A patient received closed-circuit anesthesia from a General Electric Avance S/5 (GE Healthcare, Madison, WI) anesthesia machine during a robotic abdominal procedure. With return of spontaneous ventilation at the end of the procedure, the negative airway pressure alarm began to sound, and a negative airway pressure of 10-15 cm H2O was observed with each breath. Replacing the CO2 absorber resolved the problem. There was considerable condensation on the walls of the Amsorb canister, and on disassembly, the sponge at the bottom was wet. Experimentation with an empty canister revealed that as little as 30 mL of water in the sponge can reproduce our observations.

Complications of inhaled anesthesia delivery systems

Inhaled anesthesia delivery systems (ADS) have evolved in the past 20 years from simple pneumatic machines to complex computer-controlled devices. For the purposes of this discussion, we will outline some of the potential complications that may result from the use of these systems. Because of the complexity of modern ADS, it is incumbent on the anesthesiologist to be cognizant of potential problems that may arise with their use. Even though it is now more difficult than ever for the practitioner to develop a comprehensive understanding of these machines, it remains essential for the safe practice of anesthesia. When the anesthesiologist understands the basic design differences between products from different manufacturers, it is more likely that the appropriate preoperative checks will be performed and that delivery of a safe anesthetic can be ensured. Although malpractice claims associated with anesthesia delivery systems are rare, when they do occur they may be severe, and they continue to occur. These complications may range in severity from mild hypercapnia to awareness and even death.

Root-cause analysis of an airway filter occlusion: a way to improve the reliability of the respiratory circuit

BACKGROUND

To show how root-cause analysis can identify system-level factors causing critical incidents and accidents, we present an investigation of the occlusion of an airway filter during anaesthesia.

METHOD

The investigation was based on a framework specifically developed for the analysis of medical accidents. This framework helped to identify the chronology and outcome of the case, the care management problems and the factors that led to the event. Information was obtained by interviewing the anaesthesiologist in charge of the patient.

RESULTS

Occlusion was not recognized because the filter was hidden under the drapes and below the patient's head. To reduce the frequency of this event, we recommend that filters should be visible, placed above the level of the patient's body, or mounted on the expiratory circuit, at a distance from patient's airway.

CONCLUSIONS

To allow appropriate corrective actions, critical incidents and accidents should be systematically investigated using root-cause analysis.

Anaesthetic breathing circuit obstruction due to blockage of tracheal tube connector by a foreign body--two cases

Two cases are presented which illustrate the disastrous consequences possible when an anaesthetic breathing circuit is obstructed by a foreign body. Despite reports of previous similar cases, work practices and equipment manufacture or design continue to allow for such events to occur. The importance of both pre-anaesthetic testing of the entire circuit including attachments such as the tracheal tube connector and filters, and the removal of these parts should obstruction occur, is emphasised. Use of "clear" transparent breathing circuit components and opaque or brightly coloured packaging and caps which could potentially cause obstruction should decrease the incidence and facilitate the diagnosis of this problem.