SUDDEN FAILURE OF VENTILATION BY ANAESTHESIA WORK STATION DURING SURGERY: A CASE REPORT

We encountered a case with sudden and complete interruption of fresh gas ow in anesthesia workstation. On inquiry, it was found out that there was water in the medical gas pipeline system and a simultaneous malfunction of the dryer mechanism that lead to this condition. This case report emphasizes the importance of understanding the capabilities and limitations of the drager machine as well as of any anesthesia workstations being used to administer anaesthesia. In addition, this demonstrates the importance to being able to provide immediate backup ventilation in case of 1 ventilator failure.

Effects of the reservoir bag disconnection on inspired gases during general anesthesia: a simulator-based study

Background Fresh gas decoupling is a feature of the modern anesthesia workstation, where the fresh gas flow (FGF) is diverted into the reservoir bag and is not added to the delivered tidal volume, which thus remains constant. The present study aimed to investigate the entraining of the atmospheric air into the anesthesia breathing circuit in case the reservoir bag was disconnected. Methods We conducted a simulator-based study, where the METI HPS simulator was connected to the anesthesia workstation. The effect of the disconnected reservoir bag was evaluated using oxygen (O2) and air or oxygen and nitrous oxide (N2O) as a carrier gas at different FGF rates. We disconnected the reservoir bag for 10 min during the maintenance phase. We recorded values for inspiratory O2, N2O, and sevoflurane. The time constant of the exponential process was estimated during reservoir bag disconnection. Results The difference of O2, N2O and sevoflurane concentrations, before, during, and after reservoir bag disconnection was statistically significant at 0.5, 1, and 2 L/min of FGF (p < 0.001). The largest decrease of the inspired O2 concentrations (FIO2) was detected in the case of oxygen and air as the carrier gas and an FGF of 1 L/min, when oxygen decreased from median [25th–75th percentile] 55.00% [54.00–56.00] to median 39.50% [38.00–42.50] (p < 0.001). The time constant for FIO2 during reservoir bag disconnection in oxygen and air as the carrier gas, were median 2.5, 2.5, and 1.5 min in FGF of 0.5, 1.0, and 2 L/min respectively. Conclusions During the disconnection of the anesthesia reservoir bag, the process of pharmacokinetics takes place faster compared to the wash-in and wash-out pharmacokinetic properties in the circle breathing system. The time constant was affected by the FGF rate, as well as the gradient of anesthetic gases between the anesthesia circle system and atmospheric air.

Uncovering the Drape: Observing its Impact on Communication With Anesthesia Providers

In the operating room (OR), opaque drapes are hung between the anesthesia workstation and the operating table. Because OR teams are transient and hierarchical, social order is continuously being negotiated around this partition. We hypothesized that drape transparency, a tool for reimagining the physical and symbolic confines of the OR, might alter behavior. Due to the proximity of anesthesia providers to the drape, we examined how the drape’s transparency affected “social” and “case-related” communication between them and clinicians from surgery and nursing. We observed 58 surgical cases using an OR ethogram to document interprofessional communications (344 exchanges) involving the anesthesia provider. The effect of the type drape showed a statistically significant, GzMLM F(1, 342) = 4.924, p = .027, increase only for “social” communication. The frequency of “social” communication, known to enhance collegiality, was greater when a transparent drape was substituted for the opaque drape (34.9% vs. 21.3%, respectively).