Safety & quality: Overview

Abstract
Introduction: Continuously assessing the oxygenation levels of patients to detect and prevent hypoxemia can be advantageous for safe anesthesia, especially in neonates and small infants. The oxygen reserve index (ORI) is a new parameter that can assess oxygenation through a relationship with arterial oxygen partial pressure (PaO2 ). The aim of this study was to examine whether the ORI provides a clinically relevant warning time for an impending SpO2 (pulse oximetry hemoglobin saturation) reduction in neonates and small infants.

Methods: ORI and SpO2 were measured continuously in infants aged <2 years during general anesthesia. The warning time and sensitivity of different ORI alarms for detecting impending SpO2 decrease were calculated. Subsequently, the agreement of the ORI and PaO2 with blood gas analyses was assessed.

Results: The ORI of 100 small infants and neonates with a median age of 9 months (min-max, 0-21 months) and weight of 8.35 kg (min-max, 2-13 kg) were measured. For the ORI/PaO2 correlation, 54 blood gas analyses were performed. The warning time and sensitivity of the preset ORI alarm during the entire duration of anesthesia were 84 s (25th-75th percentile, 56-102 s) and 55% (95% CI 52%-58%), and those during anesthesia induction were 63 s (40-82 s) and 56% (44%-68%), respectively. The positive predictive value of the preset ORI alarm were 18% (95% CI 17%-20%; entire duration of anesthesia) and 27% (95% CI 21%-35%; during anesthesia induction). The agreement of PaO2 intervals with the ORI intervals was poor, with a kappa of 0.00 (95% CI = [-0.18; 0.18]). The weight (p = .0129) and height (p = .0376) of the infants and neonates were correlated to the correct classification of the PaO2 interval with the ORI interval.

Conclusions: The ORI provided an early warning time for detecting an impending SpO2 decrease in small infants and neonates in the defined interval in this study. However, the sensitivity of ORI to forewarn a SpO2 decrease and the agreement of the ORI with PaO2 intervals in this real-life scenario were too poor to recommend the ORI as a useful early warning indicator for this age group.

Sugammadex has been used for more than ten years in Australia and New Zealand and has been implicated as an effective treatment, and in some cases a potential cause, of a critical incident. We aimed to identify and analyse critical incidents involving sugammadex reported to webAIRS, a de-identified voluntary online critical incident reporting system in Australia and New Zealand. We identified 116 incidents where the reporter implicated sugammadex as either a cause (23 cases) or a treatment (93 cases) during anaesthesia. There were 17 incidents suggestive of sugammadex anaphylaxis, although not all were confirmed by skin testing. There were six incidents when bradycardia was temporally related to sugammadex administration, although it was not possible to exclude other causes or contributory factors. There were nine incidents in which sugammadex was used to reverse aminosteroid-related neuromuscular blockade successfully in a 'can't intubate, can't oxygenate' (CICO) situation, and a further 67 incidents in which sugammadex was used to reverse aminosteroid neuromuscular blockade as part of the management of other critical incidents. While sugammadex was used during the management of 16 cases of anaphylaxis, there was no clear indication that this altered the course of the anaphylaxis in any of the cases. These reports indicate that sugammadex can be a potential trigger for anaphylaxis and that its use may be associated with the development of significant bradycardia. However, it is not possible to estimate or even speculate on the incidence of these sugammadex-related incidents on the basis of voluntary reporting to a database such as webAIRS. The reports also indicate that sugammadex has been used successfully to reverse residual or deep aminosteroid neuromuscular blockade in critical incident situations and to help rescue CICO scenarios. These findings provide further support for ensuring the ready availability of sugammadex wherever aminosteroid muscle relaxants are used.

Abstract
This cross-sectional overview of the second 4000 incidents reported to webAIRS has findings that are very similar to the previous overview of the first 4000 incidents. The distribution of patient age, body mass index and American Society of Anesthesiologists physical status was similar, as was anaesthetist gender, grade, location and time of day of incidents. About 35% of incidents occurred during non-elective procedures (vs. 33% in the first 4000 incidents). The proportion of incidents in the various main categories was also similar, with respiratory/airway being most common, followed by cardiovascular, medication-related and medical device or equipment-related incidents. Together these categories made up about 78% of all incidents in both overviews. The immediate outcome was comparable with reports of harm in about a quarter of incidents and a similar rate of deaths (4.7% vs. 4.2%). However, the proportion of patients who had received total intravenous anaesthesia was higher (17.6% vs. 7.7%) and the proportion of patients who received combined intravenous and inhalational anaesthesia was lower (52.3% vs. 58.4%), as was the proportion receiving local anaesthesia alone (1.6% vs. 6.7%). There was a small increase in the number of incidents resulting in unplanned admission to a high dependency or intensive care unit (18.1% vs. 13.5%). It is not clear whether these differences represent trends or random observations. About 48% of incidents were considered preventable by the reporters (vs. 52% in the first 4000). These findings support continued emphasis on human and system factors to promote and improve patient safety in anaesthesia care.