Hemodynamic Tolerance to IV Clonidine Infusion in the PICU

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.

Continuous clonidine infusion: an alternative for children on mechanical ventilation

OBJECTIVE

This study aimed to assess the clonidine infusion rate in the first 6 h, as maintenance dose (first 24 h), and in the pre-extubation period (last 24 h), as well as the cumulative dose of other sedatives and the hemodynamic response.

METHODS

This is a retrospective cohort study.

RESULTS

Children up to the age of 2 years who were admitted to the pediatric intensive care unit of a tertiary referral hospital in the south region of Brazil, between January 2017 and December 2018, were submitted to mechanical ventilation, and received continuous clonidine infusions were included in the study. The initial, maintenance, and pre-extubation doses of clonidine; the vasoactive-inotropic score; heart rate; and systolic and diastolic blood pressure of the study participants were assessed. A total of 66 patients with a median age of 4 months who were receiving clonidine infusions were included. The main indications for mechanical ventilation were acute viral bronchiolitis (56%) and pneumonia associated with acute respiratory distress syndrome (15%). The median of clonidine infusion in the first 6 h (66 patients) was 0.53 μg/kg/h (IQR 0.49-0.88), followed by 0.85 μg/kg/h (IQR 0.53-1.03) during maintenance (57 patients) and 0.63 μg/kg/h (IQR 0.54-1.01) during extubation period (42 patients) (p=0.03). No differences were observed in the doses regarding the indication for mechanical ventilation. Clonidine infusion was not associated with hemodynamic changes and showed no differences when associated with adjuvants.

CONCLUSION

Clonidine demonstrated to be a well-tolerated sedation option in pediatric patients submitted to mechanical ventilation, without relevant influence in hemodynamic variables.

Use of continuous infusion of clonidine for sedation in critically ill infants and children

BACKGROUND

Adequate sedation and analgesia are required for critically ill children in order to minimize discomfort, reduce anxiety, and facilitate care. This is commonly achieved through a combination of opioids and benzodiazepines. Prolonged use of these agents is associated with tolerance and withdrawal. Clonidine as an adjunctive sedative agent may reduce sedation-related adverse events.

OBJECTIVE

Our first aim was to describe the indication for clonidine administration and its secondary effects in a mixed cohort of critically ill children. Our secondary aim was to measure the consumption of sedatives during two study periods: before and after the use of clonidine in our pediatric intensive care unit (PICU).

METHODS

This was a single-center study conducted in a tertiary PICU and encompassed retrospective chart review of patients who received clonidine between November 2013 and April 2015. We collected data on clonidine dosage, duration of administration, indication for the prescription, and potential side effects. We analyzed the total consumption of sedatives over 18 months, before and after the introduction of clonidine in our sedation protocol.

RESULTS

A total of patients received clonidine, with a mean age of 2.2 ± 2.8 years. The primary reason for intensive care admission was respiratory failure (48%). The main indication for clonidine administration was increasing requirement for morphine and midazolam (60%). The mean duration of clonidine infusion was 9 ± 7.3 days. Bradycardia and hypotension occurred in five patients (11.6%) and nine patients (21%), respectively. These side effects did not result in any major intervention. Younger age was a risk factor for clonidine-associated bradycardia. We observed a significant decrease in morphine and midazolam consumption with clonidine as a comedication. Compared with the pre-study period, consumption decreased by 19.7% for morphine and by 59% for midazolam (calculated as milligram/admission).

CONCLUSION

Continuous infusion of clonidine in critically ill children is safe and effective. Clonidine is a sedative-sparing agent and this can help reduce complications associated with prolonged use of opioids and benzodiazepines.

Safety of clonidine used for long-term sedation in paediatric intensive care: A systematic review

AIM

Although not approved, the α-adrenoceptor agonist clonidine is considered an option for long-term sedation protocols in paediatric intensive care. We reviewed adverse effects of clonidine occurring in this indication.

METHODS

Relevant literature was systematically identified from PubMed and Embase. We included interventional and observational studies on paediatric patients admitted to intensive care units and systemically long-term sedated with clonidine-containing regimes. In duplicates, we conducted standardised and independent full-text assessment and extraction of safety data.

RESULTS

Data from 11 studies with 909 patients were analysed. The studies were heterogeneous regarding patient characteristics (age groups, comorbidity, or comedication) and sedation regimes (dosage, route, duration, or concomitant sedatives). Just four randomised controlled trials (RCTs) and one observational study had comparison groups, using placebo or midazolam. For safety outcomes, our validity evaluation showed low risk of bias only in three studies. All studies focused on haemodynamic problems, particularly bradycardia and hypotension. Observed incidences or subsequent interventions never caused concerns. However, only two RCTs allowed meaningful comparisons with control groups. Odds ratios showed no significant difference between the groups, but small sample sizes (50 and 125 patients) must be considered; pooled analyses were not reasonable.

CONCLUSION

All evaluated studies concluded that the use of clonidine in paediatric intensive care units is safe. However, a valid characterisation of the safety profile remains challenging due to limited, biased and heterogeneous data and missing investigation of long-term effects. This evaluation demonstrates the lack of data, which prevents reliable conclusions on the safety of clonidine for long-term sedation in critically ill children. For an evidence-based use, further studies are needed.

A nurse-driven analgesia and sedation protocol reduces length of PICU stay and cumulative dose of benzodiazepines after corrective surgery for tetralogy of Fallot

PURPOSE

Analgesia and sedation protocols are reported to reduce the requirement of sedative and analgesic agents, duration of mechanical ventilation, and length of pediatric intensive care unit (PICU) stay. However, these studies often were conducted based on inhomogeneous cohorts. The aim of this study was the evaluation of a nurse-driven analgesia and sedation protocol in a homogenous population of infants following corrective surgery for tetralogy of Fallot (TOF).

DESIGN AND METHODS

This retrospective analysis was conducted in a cardiac PICU of a tertiary referral center. Two cohorts of patients who underwent corrective surgery for TOF below the age of 7 months, were retrospectively evaluated before and after implementation of a nurse-driven analgesia and sedation protocol. We compared peak and cumulative doses of midazolam, morphine, and clonidine, length of PICU stay and time on mechanical ventilation.

RESULTS

A total of 33 patients were included in the preimplementation period and 32 during the postimplementation period. Implementation of the nurse-driven analgesia and sedation protocol had no effect on time on mechanical ventilation (72 hr [24-141] vs. 49 hr [24-98]), but significantly on length of PICU stay (7 days [5-14] vs. 5 days [4-7]). Cumulative doses of midazolam (7.37 mg/kg [4.70-17.65] vs. 5.0 mg/kg [2.70-9.12]) as well as peak doses of midazolam (0.22 mg·kg^-1 ·hr^-1 [0.20-0.33] vs. 0.15 mg·kg^-1 ·hr^-1 [0.13-0.20]) and morphine (50.0 µg·kg^-1 ·hr^-1 [39.7-79.9] vs. 42.5 µg·kg^-1 ·hr^-1 [29.7-51.8]) were significantly reduced. The postimplemantation group showed no increase in postoperative complications and adverse events.

PRACTICE IMPLICATIONS

The implementation of a nurse-driven analgesia and sedation protocol is safe in infants following corrective surgery for TOF. It reduces significantly the length of PICU stay, cumulative and peak doses of midazolam and peak doses of morphine.

Evaluation of an updated sedation protocol to reduce benzodiazepines in a pediatric intensive care unit

Aim: Midazolam like other benzodiazepines is supposed to be neurotoxic in small children and to represent a risk factor for the development of delirium. The aim of this study was to evaluate whether a modified analgesia and sedation protocol is feasible and effective to reduce the requirement of midazolam in neonates and young infants after cardiac surgery.Methods: Patients aged 6 months or younger who underwent surgery for congenital heart disease with cardiopulmonary bypass were enrolled and divided into a pre-modification group (January-December 2016) and after adjusting our sedation protocol into a post-modification group (January-December 2018). We assessed the doses of midazolam, morphine and clonidine as well as sedation scores according to our nurse-driven sedation protocol every 8 h until 120 h after cardiac surgery. During weaning from analgesia and sedation, children were monitored regarding withdrawal symptoms and pediatric delirium.Results: Sixty-five patients were included (33 patients in the pre-modification group, 32 patients in the post-modification group). The number of patients receiving midazolam and the cumulative dose of midazolam could be successfully reduced. The sedation scores were still within the desired target range for adequate sedation without any negative side effects.Conclusions: It is feasible and safe to reduce the use of midazolam in infants after cardiac surgery maintaining sedation goals based on a modified nurse-driven analgesia and sedation protocol.

Optimizing clonidine dosage for sedation in mechanically ventilated children: A pharmacokinetic simulation study

BACKGROUND

Clonidine is in widespread off-label use as a sedative in mechanically ventilated children, despite limited evidence of efficacy. A variety of dosage regimens have been utilized in clinical practice and in research studies. Within these studies, clonidine has inconsistently shown useful sedation properties. One of the reasons attributed to the inconsistent signs of efficacy is suboptimal clonidine dosing.

AIMS

This study aims to propose a target plasma concentration and simulate clonidine pharmacokinetics (PK) in a cohort of mechanically ventilated children to evaluate the adequacy of clonidine dosage regimens used in clinical practice and research studies.

METHODS

A literature search was undertaken to identify a clonidine pharmaockinetic-pharmacodynamics (PKPD) model, from which a target concentration for sedation was defined. Using a previously published PK model, the projected plasma concentrations of 692 mechanically ventilated children (demographics taken from a recent study) were generated. Doses from recently published clinical studies were investigated. Adequacy of each regimen to attain therapeutic clonidine plasma concentrations was assessed.

RESULTS

A target plasma concentration of above 2 µg/L was proposed. Nine dosage regimens (four intravenous boluses, four intravenous infusions, and one nasogastric route boluses) were evaluated ranging from 1 µg/kg eight hourly intravenous boluses to a regimen up to 3 µg/kg/hr continuous intravenous infusion. Regimens with a loading dose of 2 µg/kg followed by variable continuous infusion of up to 2 µg/kg/hr titrated according to sedation score appear most suitable. Doses should be halved in neonates.

CONCLUSION

The variety of dosage regimens in the previous studies of clonidine along with difficulties in the conduct of interventional studies may have contributed to the lack of efficacy data to support its use. Simulations of clonidine plasma concentrations based on known population pharmacokinetic parameters suggest a loading dose followed by higher than current practice maintenance dose infusion is required to achieve adequate steady-state concentrations early in treatment. Further PKPD studies will aid in the determination of the optimal clonidine dosage regimen.

Clonidine in pediatric anesthesia: the new panacea or a drug still looking for an indication?

PURPOSE OF REVIEW

Clonidine, an α2-receptor agonist is a widely used drug in pediatrics with a large scope of indications ranging from prevention of postoperative emergence agitation, analgesia, anxiolysis, sedation, weaning to shivering. In the era of 'opioid-free' medicine with much attention be directed toward increasing problems with opioid use, clonidine due to its global availability, low cost and safety profile has become an even more interesting option.

RECENT FINDINGS

Increasing evidence from randomised clinical trials support the use of clonidine in healthy children in the perioperative setting. Clonidine appears to significantly reduce postoperative emergence agitation, opioid consumption, shivering, nausea and vomiting. In addition, emerging evidence support the use of clonidine for sedation of critically ill children in ICUs. In this review, the current evidence for clonidine in pediatrics is described and analyzed including a meta-analysis for prevention of emergence agitation.

SUMMARY

Clonidine appears a safe and beneficial drug with moderate to high-quality evidence supporting its use in pediatric anesthesia. However, for some indications and populations such as children younger than 12 months old and those with hemodynamic instability, there is an urgent need for high-quality trials.

Hemodynamic response to β-blockers in severe sepsis and septic shock: A review of current literature

The administration of β-blockers in patients with sepsis is a trending topic in intensive care medicine since the landmark study by Morelli and colleagues, showing a striking decrease in 28-day mortality compared to standard care. While the available evidence suggests that the use of β-blockers in septic shock is safe, the effects on hemodynamics are controversial. In this paper, we review the effect of β-blockade in septic shock on hemodynamics from animal models to critically ill patients.