Unplanned Extubations in the cardiac ICU: Are we missing the beat?

Critically ill children requiring tracheal intubation and invasive mechanical ventilation have increased potential risks of harm. Unplanned extubations (UEs) cause harm that may lead to poor clinical outcomes (1). UE was described as early as 1994, along with its associated clinical impact (2). In critically ill neonates and children, UEs contribute to significant physiological instability including morbidity and mortality (1, 3, 4). Those hospitalized in the cardiac intensive care unit (CICU) represent a particularly vulnerable subset of children who may suffer from additional hospital-acquired conditions as a result of UE, including cardiac arrest, ventilator-associated pneumonia (VAP), increased duration of invasive mechanical ventilation (IMV) and need for mechanical circulatory support (5–8). The unique risk factors and outcomes of UEs in children with medical and surgical cardiac disease remain poorly understood.

The study in this issue of Pediatric Critical Care Medicine by Perry et al evaluated the UEs in critically ill children with cardiac disease (5). In this multicenter, retrospective cohort study, the authors used a large dataset from the Pediatric Cardiac Critical Care Consortium (PC⁴) registry to describe the incidence of UEs in the CICU, including risk factors and consequential harm (5). The dataset included 36,696 patients who had either UE or planned extubation in the CICU from 45 hospitals from North America over 6 years (2014–2020). In this cohort, 2.9% of all extubations were UEs, with 0.77 UE events per 100 ventilation days. The authors analyzed the association between UE and length of subsequent respiratory support, need for reintubation, mechanical circulatory support, cardiac arrest, incidence of VAP or death. The burden of harm from UE was high and unfortunately fell upon the sicker patients. Those children who were in a cardiac ICU and experienced a UE were younger and had a higher surgical complexity. These children who had UE were associated with longer ICU stay (15 days vs. 6 days) and longer hospital length of stay (29 days vs. 14 days). Further, children who suffered from UE had more cardiac arrests and required mechanical circulatory support more frequently, although mortality did not reach statistical significance.

Could nasal intubation be protective? In this study, children in the surgical cohort had a lower frequency of nasal intubations in the UE group (13.5%) when compared with children without UE (19%) with an adjusted odds ratio of 0.57 (95% confidence interval: 0.46–0.72). However, this effect was not seen in the medical cohort. Children with UE also had a higher use of non-invasive respiratory support and reintubation within 2 days. In this subgroup, the reintubation rate was relatively low (28.8%) compared with prior studies. Similarly, a modifiable risk factor for the “peri-admission” group may also include earlier extubation, as this subgroup had a shorter length of ICU stay. This suggests that there may be opportunities to target extubation sooner. This highlights the need for a better ventilation liberation process (7).

This study also provides both a richer understanding of risk factors and outcomes of UEs for critically ill pediatric cardiac population and identifies potential modifiable and non-modifiable targets for future research and quality improvement. Such modifiable risk factors may include appropriate use of restraints, different tube securement methods, and sedation- both in the medication class and level. Although these measures may better protect against UE, they may also come with a cost, such as skin breakdown or delirium. These targets must therefore be balanced with one another to achieve optimal harm mitigation, and represent a focus for further research (4, 6, 9–11).

Achieving a sustained low UE rate through quality improvement work is possible both in single centers and on a larger scale, though efforts in UE reduction in the CICU have thus far globally remained elusive (6, 7). In Klugman’s 2020 study of the Solutions for Patient Safety Collaboration (SPS), a centerline shift was noted in the PICU and NICU cohort, but not the CICU, though their reported CICU UE rate was at 0.281 events per 100 ventilation days-- much lower compared with this study (6). One of the current SPS goals is to reduce UEs over the next two years. Recommended best practice includes prospective audit and feedback of processes and bundled approaches to care. For intubated patients, bundled care includes utilizing standard anatomic reference points and securement methods for endotracheal tubes, and developing an institution specific protocol for high-risk patients. The SPS further recommends that each hospital performs a multidisciplinary review of every UE and conducts active discussions on extubation readiness. While a large variance existed in the UE rate across the PC4 cohort CICUs in this study, there is no information on which if any sites were involved in local or national UE reduction work such as SPS; a potential cofounder to consider.

This study offers useful information about the landscape of UE in CICUs as a starting point. Understanding both patient and system level risk factors sets the stage to develop risk reduction strategies. Although bound by the limitations inherent in large retrospective cohort studies, this analysis explores the cohort of critically ill children with cardiac disease in a much greater scale and depth than previously described. We are one step closer to personalizing the care of these intubated high risk patients with an eye towards harm reduction.