Cycling of Dexmedetomidine May Prevent Delirium After Liver Transplantation

Effect of intraoperative dexmedetomidine on hepatic ischemia-reperfusion injury in pediatric living-related liver transplantation: A propensity score matching analysis

Background

Hepatic ischemia-reperfusion injury (HIRI) is largely unavoidable during liver transplantation (LT). Dexmedetomidine (DEX), an α2-adrenergic agonist, exerts a variety of organ-protective effects in pediatric populations. However, evidence remains relatively limited about its hepatoprotective effects in pediatric living-related LT.

Methods

A total of 121 pediatric patients undergoing living-related LT from June 2015 to December 2018 in our hospital were enrolled. They were classified into DEX or non-DEX groups according to whether an infusion of DEX was initiated from incision to the end of surgery. Primary outcomes were postoperative liver graft function and the severity of HIRI. Multivariate logistic regression and propensity score matching (PSM) analyses were performed to identify any association.

Results

A 1:1 matching yielded 35 well-balanced pairs. Before matching, no significant difference was found in baseline characteristics between groups except for warm ischemia time, which was longer in the non-DEX group (44 [38–50] vs. 40 [37–44] min, p = 0.017). After matching, the postoperative peak lactic dehydrogenase levels decreased significantly in the DEX group than in the non-DEX group (622 [516–909] vs. 970 [648–1,490] IU/L, p = 0.002). Although there was no statistical significance, a tendency toward a decrease in moderate-to-extreme HIRI rate was noted in the DEX group compared to the non-DEX group (68.6% vs. 82.9%, p = 0.163). Patients in the DEX group also received a significantly larger dosage of epinephrine as postreperfusion syndrome (PRS) treatment (0.28 [0.17–0.32] vs. 0.17 [0.06–0.30] µg/kg, p = 0.010). However, there were no significant differences between groups in PRS and acute kidney injury incidences, mechanical ventilation duration, intensive care unit, and hospital lengths of stay. Multivariate analysis revealed a larger graft-to-recipient weight ratio (odds ratio [OR] 2.657, 95% confidence interval [CI], 1.132–6.239, p = 0.025) and intraoperative DEX administration (OR 0.333, 95% CI, 0.130–0.851, p = 0.022) to be independent predictors of moderate-to-extreme HIRI.

Conclusion

This study demonstrated that intraoperative DEX could potentially decrease the risk of HIRI but was associated with a significant increase in epinephrine requirement for PRS in pediatric living-related LT. Further studies, including randomized controlled studies, are warranted to provide more robust evidence.

Changes in Sedation Practices in Association with Delirium Screening in Infants After Cardiopulmonary Bypass

Sedation in the cardiac intensive care unit (CICU) is necessary to keep critically ill infants safe and comfortable. However, long-term use of sedatives may be associated with adverse neurodevelopmental outcomes. We aimed to examine sedation practices in the CICU after the implementation of the Cornell Assessment of Pediatric Delirium (CAPD). We hypothesize the use of the CAPD would be associated with a decrease in sedative weans at CICU discharge. This is a single institution, retrospective cohort study. The study inclusion criteria were term infants, birthweight > 2.5 kg, cardiopulmonary bypass (CPB), and mechanical ventilation (MV) on postoperative day zero. During the study period, 50 and 35 patients respectively, met criteria pre- and post-implementation of CAPD screening. Our results showed a statistically significant increase in the incidence of sedative habituation wean at CICU discharge after CAPD implementation (24% vs. 45.7%, p = 0.036). There was a statistically significant increase in exposure to opiate (56% vs. 88.6%, p = 0.001) and dexmedetomidine infusions (52% vs 80%, p = 0.008), increased likelihood of clonidine use at CICU discharge (OR 9.25, CI 2.39-35.84), and increase in the duration of intravenous sedative infusions (8.1 days vs. 5.1 days, p = 0.04) No statistical difference was found in exposure to fentanyl (42% vs. 58.8%, p = 0.13) or midazolam infusions (22% vs. 25.7%, p = 0.691); and there was no change in benzodiazepine or opiate use at CICU discharge or dosage. The prevalence of delirium in the CAPD cohort was 92%. CAPD implementation in the CICU was associated with changes in sedation practices, specifically an increase in the use of dexmedetomidine, which possibly explains the increased clonidine weans at CICU discharge. This is the first report of the association between CAPD monitoring and changes in sedative practices. Multi-center prospective studies are recommended to evaluate sedative practices, delirium, and its effects on neurodevelopment.

Impact of postoperative dexmedetomidine infusion on incidence of delirium in elderly patients undergoing major elective noncardiac surgery: a randomized clinical trial

PURPOSE

Postoperative delirium is a serious and common complication, it occurs in 13-50% of elderly patients after major surgery, and presages adverse outcomes. Emerging literature suggests that dexmedetomidine sedation in critical care units (intensive care unit) is associated with reduced incidence of delirium. However, few studies have investigated whether postoperative continuous infusion of dexmedetomidine could safely decrease the incidence of delirium in elderly patients admitted to general surgical wards after noncardiac surgery.

PATIENTS AND METHODS

This double-blind, randomized, placebo-controlled trial was conducted in patients aged 65 years or older undergoing major elective noncardiac surgery without a planned ICU stay. Eligible patients were randomly assigned to receive either dexmedetomidine (0.1 μg/kg/h) or placebo (0.9% normal saline) immediately after surgery though patient-controlled intravenous analgesia device. The primary outcome was the incidence of delirium during the first 5 postoperative days. Secondary outcomes included postoperative subjective pain scores and subjective sleep quality. The study dates were from January 2018 to January 2019.

RESULTS

A total of 557 patients were randomly assigned to receive either dexmedetomidine (n=281) or placebo (n=276). The incidence of postoperative delirium had no difference between the dexmedetomidine and placebo groups (11.7% [33 of 281] vs 13.8% [38 of 276], P=0.47). Compared with placebo group, patients in dexmedetomidine group reported significant lower numerical rating score pain scores at 3, 12, 24, and 48 hrs after surgery (all P<0.05) and significant improved Richards Campbell Sleep Questionnaire results during the first 3 postoperative days (all P<0.0001). Dexmedetomidine-related adverse events were similar between the two groups.

CONCLUSION

Postoperative continuous infusion of dexmedetomidine did not decrease the incidence of postoperative delirium in elderly patients admitted to general surgical wards after elective noncardiac surgery.