Prolonged Dexmedetomidine Infusion and Drug Withdrawal In Critically Ill Children

Adverse cardiovascular events are common during dexmedetomidine administration in neonates and infants during intensive care

AIM

This study aimed to assess the safety of a commonly used sedative, dexmedetomidine in neonates and infants during intensive care.

METHODS

A retrospective cohort study was conducted in the paediatric intensive care unit at Oulu University Hospital. The study population consisted of all children from birth up to 6 months of age who received dexmedetomidine during 2010-2016. Adverse cardiovascular outcomes were defined as abnormal heart rates or blood pressure values according to the Paediatric Early Warning Score.

RESULTS

Of the 172 infants, 56% had congenital malformation, and 48% had undergone surgery. Neonates and 1-3-month-olds experienced bradycardia (86% vs. 73% in 1-3-month-olds and 50% in 3-6-month-olds, p = 0.001) and severe bradycardia (17% vs. 14% in 1-3-month-olds and 0% in 3-6-month-olds, p = 0.005) more often than older patients. The median maximum rate of dexmedetomidine infusion was 0.86 μg/kg/h (IQR = 0.60-1.71 μg/kg/h). A dose-dependent increase in bradycardia and severe hypotension was found. Adverse cardiovascular events were managed with additional fluid boluses and discontinuation of the infusion.

CONCLUSION

Adverse cardiovascular events were common during dexmedetomidine administration in neonates and infants. Lower dexmedetomidine doses may be required in sedating neonates.

General Anesthetic Care of Obese Patients Undergoing Surgery: A Review of Current Anesthetic Considerations and Recent Advances

Obesity has long been linked to adverse health effects over time. As the prevalence of obesity continues to rise, it is important to anticipate and minimize the complications that obesity brings in the anesthesia setting during surgery. Anesthetic departments must recognize the innumerable risks when managing patients with obesity undergoing surgery, including anatomical and physiological changes as well as comorbidities such as diabetes, cardiovascular diseases, and malignancies. Therefore, the purpose of this review is to analyze the current literature and evaluate the current and recent advances in anesthetic care of obese patients undergoing surgery, to better understand the specific challenges this patient population faces. A greater understanding of the differences between anesthetic care for obese patients can help to improve patient care and the specificity of treatment. The examination of the literature will focus on differing patient outcomes and safety precautions in obese patients as compared to the general population. Specifically highlighting the differences in pre-operative, intra-operative, and post-operative care, with the aim to identify issues and present possible solutions.

Analgesia and sedation in critically ill pediatric patients: an update from the recent guidelines and point of view

In the last decades, the advancement of knowledge in analgesia and sedation for critically ill pediatric patients has been conspicuous and relevant. Many recommendations have changed to ensure patients' comfort during their intensive care unit (ICU) stay and prevent and treat sedation-related complications, as well as improve functional recovery and clinical outcomes. The key aspects of the analgosedation management in pediatrics have been recently reviewed in two consensus-based documents. However, there remains a lot to be researched and understood. With this narrative review and authors' point of view, we aimed to summarize the new insights presented in these two documents to facilitate their interpretation and application in clinical practice, as well as to outline research priorities in the field.    Conclusion: With this narrative review and authors' point of view, we aimed to summarize the new insights presented in these two documents to facilitate their interpretation and application in clinical practice, as well as to outline research priorities in the field. What is Known: • Critically ill pediatric patients receiving intensive care required analgesia and sedation to attenuate painful and stressful stimuli. •Optimal management of analgosedation is a challenge often burdened with complications such as tolerance, iatrogenic withdrawal syndrome, delirium, and possible adverse outcomes. What is New: •The new insights on the analgosedation treatment for critically ill pediatric patients delineated in the recent guidelines are summarized to identify strategies for changes in clinical practice. •Research gaps and potential for quality improvement projects are also highlighted.

Clonidine use during dexmedetomidine weaning: A systematic review

BACKGROUND

Dexmedetomidine is a centrally acting alpha-2A adrenergic agonist that is commonly used as a sedative and anxiolytic in the intensive care unit (ICU), with prolonged use increasing risk of withdrawal symptoms upon sudden discontinuation. As clonidine is an enterally available alpha-2A adrenergic agonist, it may be a suitable agent to taper off dexmedetomidine and reduce withdrawal syndromes. The appropriate dosing and conversion strategies for using enteral clonidine in this context are not known. The objective of this systematic review is to summarize the evidence of enteral clonidine application during dexmedetomidine weaning for prevention of withdrawal symptoms.

AIM

To systematically review the practice, dosing schema, and outcomes of enteral clonidine use during dexmedetomidine weaning in critically ill adults.

METHODS

This was a systematic review of enteral clonidine used during dexmedetomidine weaning in critically ill adults (≥ 18 years). Randomized controlled trials, prospective cohorts, and retrospective cohorts evaluating the use of clonidine to wean patients from dexmedetomidine in the critically ill were included. The primary outcomes of interest were dosing and titration schema of enteral clonidine and dexmedetomidine and risk factors for dexmedetomidine withdrawal. Other secondary outcomes included prevalence of adverse events associated with enteral clonidine use, re-initiation of dexmedetomidine, duration of mechanical ventilation, and ICU length of stay.

RESULTS

A total of 3427 studies were screened for inclusion with three meeting inclusion criteria with a total of 88 patients. All three studies were observational, two being prospective and one retrospective. In all included studies, the choice to start enteral clonidine to wean off dexmedetomidine was made at the discretion of the physician. Weaning time ranged from 13 to 167 h on average. Enteral clonidine was started in the prospective studies in a similar protocolized method, with 0.3 mg every 6 h. After starting clonidine, patients remained on dexmedetomidine for a median of 1-28 h. Following the termination of dexmedetomidine, two trials tapered enteral clonidine by increasing the interval every 24 h from 6 h to 8h, 12h, and 24 h, followed by clonidine discontinuation. For indicators of enteral clonidine withdrawal, the previously tolerable dosage was reinstated for several days before resuming the taper on the same protocol. The adverse events associated with enteral clonidine use were higher than patients on dexmedetomidine taper alone with increased agitation. The re-initiation of dexmedetomidine was not documented in any study. Only 17 (37%) patients were mechanically ventilated with median duration of 3.5 d for 13 patients in one of the 2 studies. ICU lengths of stay were similar.

CONCLUSION

Enteral clonidine is a strategy to wean critically ill patients from dexmedetomidine. There is an association of increased withdrawal symptoms and agitation with the use of a clonidine taper.

Recommendations for analgesia and sedation in critically ill children admitted to intensive care unit

We aim to develop evidence-based recommendations for intensivists caring for children admitted to intensive care units and requiring analgesia and sedation. A panel of national paediatric intensivists expert in the field of analgesia and sedation and other specialists (a paediatrician, a neuropsychiatrist, a psychologist, a neurologist, a pharmacologist, an anaesthesiologist, two critical care nurses, a methodologist) started in 2018, a 2-year process. Three meetings and one electronic-based discussion were dedicated to the development of the recommendations (presentation of the project, selection of research questions, overview of text related to the research questions, discussion of recommendations). A telematic anonymous consultation was adopted to reach the final agreement on recommendations. A formal conflict-of-interest declaration was obtained from all the authors. Eight areas of direct interest and one additional topic were considered to identify the best available evidence and to develop the recommendations using the Evidence-to-Decision framework according to the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. For each recommendation, the level of evidence, the strength of the recommendation, the benefits, the harms and the risks, the benefit/harm balance, the intentional vagueness, the values judgement, the exclusions, the difference of the opinions, the knowledge gaps, and the research opportunities were reported. The panel produced 17 recommendations. Nine were evaluated as strong, 3 as moderate, and 5 as weak. Conclusion: a panel of national experts achieved consensus regarding recommendations for the best care in terms of analgesia and sedation in critically ill children.

Biased, Bitopic, Opioid–Adrenergic Tethered Compounds May Improve Specificity, Lower Dosage and Enhance Agonist or Antagonist Function with Reduced Risk of Tolerance and Addiction

This paper proposes the design of combination opioid–adrenergic tethered compounds to enhance efficacy and specificity, lower dosage, increase duration of activity, decrease side effects, and reduce risk of developing tolerance and/or addiction. Combinations of adrenergic and opioid drugs are sometimes used to improve analgesia, decrease opioid doses required to achieve analgesia, and to prolong the duration of analgesia. Recent mechanistic research suggests that these enhanced functions result from an allosteric adrenergic binding site on opioid receptors and, conversely, an allosteric opioid binding site on adrenergic receptors. Dual occupancy of the receptors maintains the receptors in their high affinity, most active states; drops the concentration of ligand required for full activity; and prevents downregulation and internalization of the receptors, thus inhibiting tolerance to the drugs. Activation of both opioid and adrenergic receptors also enhances heterodimerization of the receptors, additionally improving each drug’s efficacy. Tethering adrenergic drugs to opioids could produce new drug candidates with highly desirable features. Constraints—such as the locations of the opioid binding sites on adrenergic receptors and adrenergic binding sites on opioid receptors, length of tethers that must govern the design of such novel compounds, and types of tethers—are described and examples of possible structures provided.

Challenges in Nursing Care of Children With Substance Withdrawal Syndrome in the PICU

Introduction

Substance withdrawal is one of the most common advert events in the Pediatric Intensive Care Unit (PICU), as the administration of potent opiates and sedative drugs is frequently performed several times each day.

Objectives

The present study explored the challenges in nursing care of children with substance withdrawal syndrome in the PICU.

Method

The study has an explorative and descriptive semi-structured qualitative interview design, with a strategic selection of informants. It was conducted at one out of three pediatric intensive care units in Sweden.

Results

Three different main themes were identified describing the different challenges regarding withdrawal symptoms: monitor the child’s interest, work with structured support, and understand the observation.

Conclusions

There is a discrepancy between the medical perspective and the nursing care perspective regarding children in PICU suffering from withdrawal syndrome. The lack of joint guidelines, language, and nursing diagnoses may lead to subjective evaluations and increase suffering for these children.

Clonidine for the Treatment of Agitation After Dexmedetomidine Discontinuation in Pediatric Patients: A Retrospective Cohort Study

OBJECTIVE

Dexmedetomidine has become a widely used drug in PICUs for sedation. We aim to determine the effects of clonidine on pediatric patients after dexmedetomidine use.

METHODS

This was a retrospective cohort study that evaluated all pediatric patients admitted to a tertiary PICU who received dexmedetomidine infusion for >48 hours. Outcomes in patients exposed to clonidine (CLON) were compared with those of patients who were not exposed (NoCLON).

RESULTS

A total of 216 patients were included in this study (43 CLON and 173 NoCLON). The primary outcome, agitation, was less in the CLON cohort (9.3%) than in the NoCLON cohort (9.3% versus 29.5%, respectively; p < 0.01). Hospital LOS was longer in the CLON group (59 versus 20 days, p < 0.01), as was PICU LOS (37.4 versus 11.1 days, p < 0.01). There was no significant difference in the occurrence of increased heart rate or blood pressure between the 2 cohorts. Patients exposed to concurrent midazolam and opioid infusions had higher incidence of agitation when they did not receive clonidine (CLON 8% versus NoCLON 37%, OR 0.15; 95% CI, 0.05-0.51; p < 0.01). In contrast, there was no difference in the incidence of agitation for the CLON group versus the NoCLON group when dexmedetomidine was administered alone (25% versus 19%, OR 1.4; p = 0.99).

CONCLUSIONS

Our study confirms the importance and effectiveness of clonidine to treat agitation after dexmedetomidine discontinuation. A validated withdrawal scoring tool can help better define dexmedetomidine withdrawal in pediatric patients.

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.

Towards Evidence-Based Weaning: a Mechanism-Based Pharmacometric Model to Characterize Iatrogenic Withdrawal Syndrome in Critically Ill Children

For the management of iatrogenic withdrawal syndrome (IWS) in children, a quantitative understanding of the dynamics of IWS of commonly used opioids and sedatives is lacking. Here, we introduce a new mechanism-based pharmacokinetic-pharmacodynamic (PKPD) modeling approach for studying IWS in pediatric clinical datasets. One thousand seven hundred eighty-two NRS_withdrawal scores of IWS severity were analyzed, which were collected from 81 children (age range: 1 month–18 years) that received opioids or sedatives by continuous infusion for 5 days or more. These data were successfully fitted with a PKPD model consisting of a plasma and a dependence compartment that well characterized the dynamics of IWS from morphine, fentanyl, and ketamine. The results suggest that (1) instead of decreasing the infusion rate by a set percentage at set intervals, it would be better to lengthen the weaning period when higher infusion rates are administered prior to weaning; (2) for fentanyl specifically, the risk of IWS might be lower when weaning with smaller dose reductions every 12 h instead of weaning with greater dose reductions every 48 h. The developed PKPD model can be used to evaluate the risk of IWS over time and the extent to which it is affected by different weaning strategies. The results yield hypotheses that could guide future clinical research on optimal weaning strategies. The mechanism-based PKPD modeling approach can be applied in other datasets to characterize the IWS dynamics of other drugs used in pediatric intensive care.

Short-Acting Sedative-Analgesic Drugs Protect Against Development of Ventilator-Associated Events in Children: Secondary Analysis of the EUVAE Study

BACKGROUND

The U.S. Centers for Disease Control and Prevention proposed a shift in its surveillance paradigm from ventilator-associated pneumonia to ventilator-associated events (VAE) to broaden the focus of prevention and achieve a greater impact on outcomes. The main objective of the present study was to identify factors associated with pediatric VAEs in children undergoing mechanical ventilation ≥ 48 h.

METHODS

This was a secondary analysis of a pediatric cohort of a multicenter prospective study. Children who underwent mechanical ventilation ≥ 48 h were included. Exclusion criteria were previous ventilation, extracorporeal life support, and right-to-left shunt or pulmonary hypertension. In the subjects with multiple episodes of mechanical ventilation, only the first episode was considered. Remifentanil and propofol are classified as short-acting sedative and analgesic agents. Pediatric VAE is defined as an "increase in PEEP ≥ 2 cm of H₂O, an increase in [Formula: see text] of 0.20, or an increase in [Formula: see text] of 0.15 plus an increase in PEEP ≥ 1 cm of H₂O sustained for ≥1 d. Associations with pediatric VAE were estimated through multivariate Cox proportional hazards analysis. Hazard ratios and 95% CI were computed.

RESULTS

In a cohort of 90 children, 24 pediatric VAEs were documented in 906 ventilator-days. Pediatric VAEs developed after a median of 4.5 (interquartile range, 4-7.25) d. Surgical admissions, spontaneous breathing trials, early mobility, vasopressors, red blood cell units transfusion, type of sedation (continuous vs intermittent), benzodiazepine use for >3 d, and pharmacologic paralysis were not associated with pediatric VAE, whereas the use of continuous short-acting sedative-analgesic agents was identified as a strong protective factor against pediatric VAE (hazard ratio 0.06 [95% CI 0.007-0.5]).

CONCLUSIONS

Treatment with short-acting sedative-analgesic agents should be preferred for sedation of mechanically ventilated children in intensive care.

Prevention of Withdrawal in Pediatric Patients Receiving Long-term Dexmedetomidine Infusions

OBJECTIVE

Determine if the addition of clonidine was associated with a decreased incidence of dexmedetomidine withdrawal in patients who received prolonged dexmedetomidine infusions.

METHODS

This was a retrospective observational cohort study conducted at a single-center PICU in an academic children's hospital. Children 1 month to 18 years of age who received dexmedetomidine infusion for 5 days or longer were included in the study.

RESULTS

Fifty patients met the inclusion criteria with 15 patients who received clonidine and 35 who received a dexmedetomidine wean alone. Withdrawal criteria included blood pressure changes, heart rate changes, and documented agitation. Overall, there was no difference in change in blood pressure or documented agitation between groups. Patients who did not receive clonidine had a greater number of heart rate readings above normal for age following discontinuation of the infusion, yet this was not statistically significant. Potentially more importantly, the addition of clonidine did not impact the duration of dexmedetomidine wean or the PICU length of stay after dexmedetomidine discontinuation.

CONCLUSIONS

The addition of clonidine while weaning a long-term dexmedetomidine infusion did not lead to lower blood pressures or agitation, but did lead to decreased percentage of heart rates above the age-appropriate range. The clinical significance of this is unknown, and further investigation is warranted. The addition of clonidine did not decrease time to weaning off dexmedetomidine or shorten PICU length of stay.

The Impact of a Clonidine Transition Protocol on Dexmedetomidine Withdrawal in Critically Ill Pediatric Patients

OBJECTIVES

This study describes our experience with a clonidine transition protocol to prevent dexmedetomidine (DEX) withdrawal in critically ill pediatric patients.

METHODS

Retrospective review of electronic medical records of patients in the pediatric intensive care unit of a single tertiary children's hospital. All patients up to 19 years of age, who received concomitant DEX infusion and enteral clonidine between June 1, 2016, and May 31, 2018, were included.

RESULTS

Two of 24 encounters had DEX restarted for withdrawal (8.3%). Five of 14 encounters who were transitioned to clonidine 2 mcg/kg every 6 hours required an increased dose, and 1 of 10 encounters transitioned to clonidine 4 mcg/kg every 6 hours required an increased dose (36% vs 10%, p = 0.21). For encounters with clonidine dose increases, 5 of 6 had improvements in Withdrawal Assessment Tool-1 (WAT-1) scores. Of these 5 encounters, 4 had decreasing or stable opioid and sedative requirements and 1 was transitioned to methadone. No encounters required discontinuation of clonidine owing to adverse events. Two of 24 encounters met our safety endpoint. One received a fluid bolus during the clonidine transition with no change in clonidine dosing, while the other had clonidine dose decreased for asymptomatic bradycardia.

CONCLUSIONS

The 24 encounters in our retrospective study add to the limited literature available to describe dosing, initiation time, and duration of clonidine to prevent withdrawal from DEX in critically ill pediatric patients. Further research is needed to clarify the optimal dosing and duration of clonidine to prevent DEX withdrawal in pediatric patients.

Dexmedetomidine in Enhanced Recovery After Surgery (ERAS) Protocols for Postoperative Pain

PURPOSE OF REVIEW

Effective acute pain management has evolved considerably in recent years and is a primary area of focus in attempts to defend against the opioid epidemic. Persistent postsurgical pain (PPP) has an incidence of up to 30-50% and has negative outcome of quality of life and negative burden on individuals, family, and society. The 2016 American Society of Anesthesiologists (ASA) guidelines states that enhanced recovery after surgery (ERAS) forms an integral part of Perioperative Surgical Home (PSH) and is now recommended to use a multimodal opioid-sparing approach for management of postoperative pain. As such, dexmedetomidine is now being used as part of ERAS protocols along with regional nerve blocks and other medications, to create a satisfactory postoperative outcome with reduced opioid consumption in the Post anesthesia care unit (PACU).

RECENT FINDINGS

Dexmedetomidine, a selective alpha2 agonist, possesses analgesic effects and has a different mechanism of action when compared with opioids. When dexmedetomidine is initiated at the end of a procedure, it has a better hemodynamic stability and pain response than ropivacaine. Dexmedetomidine can be used as an adjuvant in epidurals with local anesthetic sparing effects. Its use during nerve blocks results in reduced postoperative pain. Also, local infiltration of IV dexmedetomidine is associated with earlier discharge from PACU. Perioperative use of dexmedetomidine has significantly improved postoperative outcomes when used as part of ERAS protocols. An in-depth review of the use of dexmedetomidine in ERAS protocols is presented for clinical anesthesiologists.

Evaluating the Transition From Dexmedetomidine to Clonidine for the Prevention of Withdrawal in Critically Ill Pediatric Patients

OBJECTIVES

To evaluate clonidine for preventing withdrawal from dexmedetomidine infusions and describe the incidence of withdrawal symptoms and adverse cardiovascular effects in critically ill pediatric patients.

METHODS

Retrospective, descriptive study of patients in Advocate Children's Hospital-Park Ridge PICU who received dexmedetomidine infusion for ≥72 hours, followed by clonidine for ≥48 hours, between January 1, 2015, and August 31, 2017.

RESULTS

Thirty-eight patients (median age 4.3 years; IQR, 2-11.5) received 39 dexmedetomidine courses. The median duration of dexmedetomidine exposure was 7.6 days (IQR, 5-11.5) at an average dose of 1 mcg/kg/hr. The median dose of clonidine at initiation was 8.3 mcg/kg/day (for <50 kg) and 4.1 mcg/kg/day (for ≥50 kg). The most common oral administration frequency was every 8 hours. Dexmedetomidine infusions for 7 days or longer and a higher dexmedetomidine dose 24 hours prior to clonidine transition both correlated with increased initial clonidine doses. Fourteen patients (37%) had at least 1 WAT-1 score of ≥3 during the transition between dexmedetomidine and clonidine, with 7 (18%) requiring an increase in sedation. Adverse cardiovascular events were possibly attributable to dexmedetomidine and/or clonidine in 4 patients.

CONCLUSIONS

Patients receiving prolonged infusions of dexmedetomidine may transition to clonidine to help prevent withdrawal symptoms. Duration of dexmedetomidine infusion of 7 days or longer and higher average dexmedetomidine dose 24 hours prior to the transition are important considerations when determining the initial clonidine dose. Transition from dexmedetomidine to clonidine was found to be safe and efficacious in our patients, with minimal adverse effects.