Systemic opioids versus other analgesics and sedatives for postoperative pain in neonates

Long-term effects of neonatal pain and sucrose treatment

Purpose

In neonatal intensive care units, applying sucrose solution for analgesia is now a routine treatment for mild procedural pain. Studies of animal and human infants provide clear evidence of benefits in the short term, but few studies have investigated the long term benefits. Thus, we determined whether sucrose could ameliorate painful stimulation during infancy in Sprague-Dawley rats and also explored the long-term effects of repeated sucrose administration during infancy. Female and male rats were included to investigate sex-related differences.

Methods

Rat pups were stimulated either with painful or tactile stimuli for the first 14 days of their lives. Pups were pretreated either with sucrose or not treated before stimulation. Behavioral tests were conducted during adolescence and adulthood. Hotplate, rotarod, open field, elevated plus maze, and radial arm water maze tests were employed to assess the behavioral consequences of early life manipulations and treatments.

Results

Painful stimulation during infancy increased the sensitivity to pain later in life, and sucrose did not remedy this effect. Motility, coordination, anxiety, and cognition tests in adulthood obtained mixed results. Pain during infancy appeared to increase anxiety during adulthood. Learning and memory in adulthood were affected by pain during infancy, and sucrose had a negative effect even in the absence of pain. No sex-related differences were observed in any of the behavioral tests by employing this model of neonatal pain.

Conclusion

Painful stimulation during infancy resulted in deficiencies in some behavioral tests later in life. Sucrose pretreatment did not mitigate these shortcomings and it actually resulted in negative outcomes.

Diclofenac for acute postoperative pain in children

BACKGROUND

Many children undergo various surgeries, which often lead to acute postoperative pain. This pain influences recovery and quality of life. Non-steroidal anti-inflammatory drugs (NSAIDs), specifically cyclo-oxygenase (COX) inhibitors such as diclofenac, can be used to treat pain and reduce inflammation. There is uncertainty regarding diclofenac's benefits and harms compared to placebo or other drugs for postoperative pain.

OBJECTIVES

To assess the efficacy and safety of diclofenac (any dose) for acute postoperative pain management in children compared with placebo, other active comparators, or diclofenac administered by different routes (e.g. oral, rectal, etc.) or strategies (e.g. 'as needed' versus 'as scheduled').

SEARCH METHODS

We used standard, extensive Cochrane search methods. We searched CENTRAL, MEDLINE, and trial registries on 11 April 2022.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) in children under 18 years of age undergoing surgery that compared diclofenac (delivered in any dose and route) to placebo or any active pharmacological intervention. We included RCTs comparing different administration routes of diclofenac and different strategies.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. Our primary outcomes were: pain relief (PR) reported by the child, defined as the proportion of children reporting 50% or better postoperative pain relief; pain intensity (PI) reported by the child; adverse events (AEs); and serious adverse events (SAEs). We presented results using risk ratios (RR), mean differences (MD), and standardised mean differences (SMD), with the associated confidence intervals (CI).

MAIN RESULTS

We included 32 RCTs with 2250 children. All surgeries were done using general anaesthesia. Most studies (27) included children above age three. Only two studies had an overall low risk of bias; 30 had an unclear or high risk of bias in one or several domains. Diclofenac versus placebo (three studies) None of the included studies reported on PR or PI. We are very uncertain about the benefits and harms of diclofenac versus placebo on nausea/vomiting (RR 0.83, 95% CI 0.38 to 1.80; 2 studies, 100 children) and any reported bleeding (RR 3.00, 95% CI 0.34 to 26.45; 2 studies, 100 children), both very low-certainty evidence. None of the included studies reported SAEs. Diclofenac versus opioids (seven studies) We are very uncertain if diclofenac reduces PI at 2 to 24 hours postoperatively compared to opioids (median pain intensity 0.3 (interquartile range (IQR) 0.0 to 2.5) for diclofenac versus median 0.7 (IQR 0.1 to 2.4) in the opioid group; 1 study, 50 children; very low-certainty evidence). None of the included studies reported on PR or PI for other time points. Diclofenac probably results in less nausea/vomiting compared to opioids (41.0% in opioids, 31.0% in diclofenac; RR 0.75, 95% CI 0.58 to 0.96; 7 studies, 463 participants), and probably increases any reported bleeding (5.4% in opioids, 16.5% in diclofenac; RR 3.06, 95% CI 1.31 to 7.13; 2 studies, 222 participants), both moderate-certainty evidence. None of the included studies reported SAEs. Diclofenac versus paracetamol (10 studies) None of the included studies assessed child-reported PR. Compared to paracetamol, we are very uncertain if diclofenac: reduces PI at 0 to 2 hours postoperatively (SMD -0.45, 95% CI -0.74 to -0.15; 2 studies, 180 children); reduces PI at 2 to 24 hours postoperatively (SMD -0.64, 95% CI -0.89 to -0.39; 3 studies, 300 children); reduces nausea/vomiting (RR 0.47, 95% CI 0.25 to 0.87; 5 studies, 348 children); reduces bleeding events (RR 0.57, 95% CI 0.12 to 2.62; 5 studies, 332 participants); or reduces SAEs (RR 0.50, 95% CI 0.05 to 5.22; 1 study, 60 children). The evidence certainty was very low for all outcomes. Diclofenac versus bupivacaine (five studies) None of the included studies reported on PR or PI. Compared to bupivacaine, we are very uncertain about the effect of diclofenac on nausea/vomiting (RR 1.28, 95% CI 0.58 to 2.78; 3 studies, 128 children) and SAEs (RR 4.52, 95% CI 0.23 to 88.38; 1 study, 38 children), both very low-certainty evidence. Diclofenac versus active pharmacological comparator (10 studies) We are very uncertain about the benefits and harms of diclofenac versus any other active pharmacological comparator (dexamethasone, pranoprofen, fluorometholone, oxybuprocaine, flurbiprofen, lignocaine), and for different routes and delivery of diclofenac, due to few and small studies, no reporting of key outcomes, and very low-certainty evidence for the reported outcomes. We are unable to draw any meaningful conclusions from the numerical results.

AUTHORS' CONCLUSIONS

We remain uncertain about the efficacy of diclofenac compared to placebo, active comparators, or by different routes of administration, for postoperative pain management in children. This is largely due to authors not reporting on clinically important outcomes; unclear reporting of the trials; or poor trial conduct reducing our confidence in the results. We remain uncertain about diclofenac's safety compared to placebo or active comparators, except for the comparison of diclofenac with opioids: diclofenac probably results in less nausea and vomiting compared with opioids, but more bleeding events. For healthcare providers managing postoperative pain, diclofenac is a COX inhibitor option, along with other pharmacological and non-pharmacological approaches. Healthcare providers should weigh the benefits and risks based on what is known of their respective pharmacological effects, rather than known efficacy. For surgical interventions in which bleeding or nausea and vomiting are a concern postoperatively, the risks of adverse events using opioids or diclofenac for managing pain should be considered.

Opioids for procedural pain in neonates

BACKGROUND

Neonates might be exposed to numerous painful procedures due to diagnostic reasons, therapeutic interventions, or surgical procedures. Options for pain management include opioids, non-pharmacological interventions, and other drugs. Morphine, fentanyl, and remifentanil are the opioids most often used in neonates. However, negative impact of opioids on the structure and function of the developing brain has been reported.

OBJECTIVES

To evaluate the benefits and harms of opioids in term or preterm neonates exposed to procedural pain, compared to placebo or no drug, non-pharmacological intervention, other analgesics or sedatives, other opioids, or the same opioid administered by a different route.

SEARCH METHODS

We used standard, extensive Cochrane search methods. The latest search date was December 2021.

SELECTION CRITERIA

We included randomized controlled trials conducted in preterm and term infants of a postmenstrual age (PMA) up to 46 weeks and 0 days exposed to procedural pain where opioids were compared to 1) placebo or no drug; 2) non-pharmacological intervention; 3) other analgesics or sedatives; 4) other opioids; or 5) the same opioid administered by a different route.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Our primary outcomes were pain assessed with validated methods and any harms. We used a fixed-effect model with risk ratio (RR) for dichotomous data and mean difference (MD) for continuous data, and their confidence intervals (CI). We used GRADE to assess the certainty of the evidence for each outcome.

MAIN RESULTS

We included 13 independent studies (enrolling 823 newborn infants): seven studies compared opioids to no treatment or placebo (the main comparison in this review), two studies to oral sweet solution or non-pharmacological intervention, and five studies (of which two were part of the same study) to other analgesics and sedatives. All studies were performed in a hospital setting. Opioids compared to placebo or no drug Compared to placebo, opioids probably reduce pain score assessed with the Premature Infant Pain Profile (PIPP)/PIPP-Revised (PIPP-R) scale during the procedure (MD -2.58, 95% CI -3.12 to -2.03; 199 participants, 3 studies; moderate-certainty evidence); may reduce Neonatal Infant Pain Scale (NIPS) during the procedure (MD -1.97, 95% CI -2.46 to -1.48; 102 participants, 2 studies; low-certainty evidence); and may result in little to no difference in pain score assessed with the Douleur Aiguë du Nouveau-né (DAN) scale one to two hours after the procedure (MD -0.20, 95% CI -2.21 to 1.81; 42 participants, 1 study; low-certainty evidence). The evidence is very uncertain about the effect of opioids on pain score assessed with the PIPP/PIPP-R scale up to 30 minutes after the procedure (MD 0.14, 95% CI -0.17 to 0.45; 123 participants, 2 studies; very low-certainty evidence) or one to two hours after the procedure (MD -0.83, 95% CI -2.42 to 0.75; 54 participants, 2 studies; very low-certainty evidence). The evidence is very uncertain about the effect of opioids on episodes of bradycardia (RR 3.19, 95% CI 0.14 to 72.69; 172 participants, 3 studies; very low-certainty evidence). Opioids may result in an increase in episodes of apnea compared to placebo (RR 3.15, 95% CI 1.08 to 9.16; 199 participants, 3 studies; low-certainty evidence): with one study reporting a concerning increase in severe apnea (RR 7.44, 95% CI 0.42 to 132.95; 31 participants, 1 study; very low-certainty). The evidence is very uncertain about the effect of opioids on episodes of hypotension (RR not estimable, risk difference 0.00, 95% CI -0.06 to 0.06; 88 participants, 2 studies; very low-certainty evidence). No studies reported parent satisfaction with care provided in the neonatal intensive care unit (NICU). Opioids compared to non-pharmacological intervention The evidence is very uncertain about the effect of opioids on pain score assessed with the Crying Requires oxygen Increased vital signs Expression Sleep (CRIES) scale during the procedure when compared to facilitated tucking (MD -4.62, 95% CI -6.38 to -2.86; 100 participants, 1 study; very low-certainty evidence) or sensorial stimulation (MD 0.32, 95% CI -1.13 to 1.77; 100 participants, 1 study; very low-certainty evidence). The other main outcomes were not reported. Opioids compared to other analgesics or sedatives The evidence is very uncertain about the effect of opioids on pain score assessed with the PIPP/PIPP-R during the procedure (MD -0.29, 95% CI -1.58 to 1.01; 124 participants, 2 studies; very low-certainty evidence); up to 30 minutes after the procedure (MD -1.10, 95% CI -2.82 to 0.62; 12 participants, 1 study; very low-certainty evidence); and one to two hours after the procedure (MD -0.17, 95% CI -2.22 to 1.88; 12 participants, 1 study; very low-certainty evidence). No studies reported any harms. The evidence is very uncertain about the effect of opioids on episodes of apnea during (RR 3.27, 95% CI 0.85 to 12.58; 124 participants, 2 studies; very low-certainty evidence) and after the procedure (RR 2.71, 95% CI 0.11 to 64.96; 124 participants, 2 studies; very low-certainty evidence) and on hypotension (RR 1.34, 95% CI 0.32 to 5.59; 204 participants, 3 studies; very low-certainty evidence). The other main outcomes were not reported. We identified no studies comparing different opioids (e.g. morphine versus fentanyl) or different routes for administration of the same opioid (e.g. morphine enterally versus morphine intravenously).

AUTHORS' CONCLUSIONS

Compared to placebo, opioids probably reduce pain score assessed with PIPP/PIPP-R scale during the procedure; may reduce NIPS during the procedure; and may result in little to no difference in DAN one to two hours after the procedure. The evidence is very uncertain about the effect of opioids on pain assessed with other pain scores or at different time points. The evidence is very uncertain about the effect of opioids on episodes of bradycardia, hypotension or severe apnea. Opioids may result in an increase in episodes of apnea. No studies reported parent satisfaction with care provided in the NICU. The evidence is very uncertain about the effect of opioids on any outcome when compared to non-pharmacological interventions or to other analgesics. We identified no studies comparing opioids to other opioids or comparing different routes of administration of the same opioid.

Systemic opioid regimens for postoperative pain in neonates

BACKGROUND

Postoperative pain clinical management in neonates has always been a challenging medical issue. Worldwide, several systemic opioid regimens are available for pediatricians, neonatologists, and general practitioners to control pain in neonates undergoing surgical procedures. However, the most effective and safe regimen is still unknown in the current body of literature.

OBJECTIVES

To determine the effects of different regimens of systemic opioid analgesics in neonates submitted to surgery on all-cause mortality, pain, and significant neurodevelopmental disability. Potentially assessed regimens might include: different doses of the same opioid, different routes of administration of the same opioid, continuous infusion versus bolus administration, or 'as needed' administration versus 'as scheduled' administration.

SEARCH METHODS

Searches were conducted in June 2022 using the following databases: Cochrane Central Register of Controlled Trials [CENTRAL], PubMed, and CINAHL. Trial registration records were identified via CENTRAL and an independent search of the ISRCTN registry.

SELECTION CRITERIA

We included randomized controlled trials (RCTs), quasi-randomized, cluster-randomized, and cross-over controlled trials evaluating systemic opioid regimens' effects on postoperative pain in neonates (pre-term or full-term). We considered suitable for inclusion: I) studies evaluating different doses of the same opioid; 2) studies evaluating different routes of administration of the same opioid; 3) studies evaluating the effectiveness of continuous infusion versus bolus infusion; and 4) studies establishing an assessment of an 'as needed' administration versus 'as scheduled' administration.

DATA COLLECTION AND ANALYSIS

According to Cochrane methods, two investigators independently screened retrieved records, extracted data, and appraised the risk of bias. We stratified meta-analysis by the type of intervention: studies evaluating the use of opioids for postoperative pain in neonates through continuous infusion versus bolus infusion and studies assessing the 'as needed' administration versus 'as scheduled' administration. We used the fixed-effect model with risk ratio (RR) for dichotomous data and mean difference (MD), standardized mean difference (SMD), median, and interquartile range (IQR) for continuous data. Finally, we used the GRADEpro approach for primary outcomes to evaluate the quality of the evidence across included studies.

MAIN RESULTS

In this review, we included seven randomized controlled clinical trials (504 infants) from 1996 to 2020. We identified no studies comparing different doses of the same opioid, or different routes. The administration of continuous opioid infusion versus bolus administration of opioids was evaluated in six studies, while one study compared 'as needed' versus 'as scheduled' administration of morphine given by parents or nurses. Overall, the effectiveness of continuous infusion of opioids over bolus infusion as measured by the visual analog scale (MD 0.00, 95% confidence interval (CI) -0.23 to 0.23; 133 participants, 2 studies; I² = 0); or using the COMFORT scale (MD -0.07, 95% CI -0.89 to 0.75; 133 participants, 2 studies; I² = 0), remains unclear due to study designs' limitations, such as the unclear risk of attrition, reporting bias, and imprecision among reported results (very low certainty of the evidence).  None of the included studies reported data on other clinically important outcomes such as all-cause mortality rate during hospitalization, major neurodevelopmental disability, the incidence of severe retinopathy of prematurity or intraventricular hemorrhage, and cognitive- and educational-related outcomes.  AUTHORS' CONCLUSIONS: Limited evidence is available on continuous infusion compared to intermittent boluses of systemic opioids. We are uncertain whether continuous opioid infusion reduces pain compared with intermittent opioid boluses; none of the studies reported the other primary outcomes of this review, i.e. all-cause mortality during initial hospitalization, significant neurodevelopmental disability, or cognitive and educational outcomes among children older than five years old. Only one small study reported on morphine infusion with parent- or nurse-controlled analgesia.

Opioids for procedural pain in neonates

BACKGROUND

Neonates might be exposed to numerous painful procedures due to diagnostic reasons, therapeutic interventions, or surgical procedures. Options for pain management include opioids, non-pharmacological interventions, and other drugs. Morphine, fentanyl, and remifentanil are the opioids most often used in neonates. However, negative impact of opioids on the structure and function of the developing brain has been reported.

OBJECTIVES

To evaluate the benefits and harms of opioids in term or preterm neonates exposed to procedural pain, compared to placebo or no drug, non-pharmacological intervention, other analgesics or sedatives, other opioids, or the same opioid administered by a different route.

SEARCH METHODS

We used standard, extensive Cochrane search methods. The latest search date was December 2021.

SELECTION CRITERIA

We included randomized controlled trials conducted in preterm and term infants of a postmenstrual age (PMA) up to 46 weeks and 0 days exposed to procedural pain where opioids were compared to 1) placebo or no drug; 2) non-pharmacological intervention; 3) other analgesics or sedatives; 4) other opioids; or 5) the same opioid administered by a different route.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Our primary outcomes were pain assessed with validated methods and any harms. We used a fixed-effect model with risk ratio (RR) for dichotomous data and mean difference (MD) for continuous data, and their confidence intervals (CI). We used GRADE to assess the certainty of the evidence for each outcome.

MAIN RESULTS

We included 13 independent studies (enrolling 823 newborn infants): seven studies compared opioids to no treatment or placebo (the main comparison in this review), two studies to oral sweet solution or non-pharmacological intervention, and five studies (of which two were part of the same study) to other analgesics and sedatives. All studies were performed in a hospital setting. Opioids compared to placebo or no drug Compared to placebo, opioids probably reduce pain score assessed with the Premature Infant Pain Profile (PIPP)/PIPP-Revised (PIPP-R) scale during the procedure (MD -2.58, 95% CI -3.12 to -2.03; 199 participants, 3 studies; moderate-certainty evidence); may reduce Neonatal Infant Pain Scale (NIPS) during the procedure (MD -1.97, 95% CI -2.46 to -1.48; 102 participants, 2 studies; low-certainty evidence); and may result in little to no difference in pain score assessed with the Douleur Aiguë du Nouveau-né (DAN) scale one to two hours after the procedure (MD -0.20, 95% CI -2.21 to 1.81; 42 participants, 1 study; low-certainty evidence). The evidence is very uncertain about the effect of opioids on pain score assessed with the PIPP/PIPP-R scale up to 30 minutes after the procedure (MD 0.14, 95% CI -0.17 to 0.45; 123 participants, 2 studies; very low-certainty evidence) or one to two hours after the procedure (MD -0.83, 95% CI -2.42 to 0.75; 54 participants, 2 studies; very low-certainty evidence). No studies reported any harms. The evidence is very uncertain about the effect of opioids on episodes of bradycardia (RR 3.19, 95% CI 0.14 to 72.69; 172 participants, 3 studies; very low-certainty evidence). Opioids may result in an increase in episodes of apnea compared to placebo (RR 3.15, 95% CI 1.08 to 9.16; 199 participants, 3 studies; low-certainty evidence). The evidence is very uncertain about the effect of opioids on episodes of hypotension (RR not estimable, risk difference 0.00, 95% CI -0.06 to 0.06; 88 participants, 2 studies; very low-certainty evidence). No studies reported parent satisfaction with care provided in the neonatal intensive care unit (NICU). Opioids compared to non-pharmacological intervention The evidence is very uncertain about the effect of opioids on pain score assessed with the Crying Requires oxygen Increased vital signs Expression Sleep (CRIES) scale during the procedure when compared to facilitated tucking (MD -4.62, 95% CI -6.38 to -2.86; 100 participants, 1 study; very low-certainty evidence) or sensorial stimulation (MD 0.32, 95% CI -1.13 to 1.77; 100 participants, 1 study; very low-certainty evidence). The other main outcomes were not reported. Opioids compared to other analgesics or sedatives The evidence is very uncertain about the effect of opioids on pain score assessed with the PIPP/PIPP-R during the procedure (MD -0.29, 95% CI -1.58 to 1.01; 124 participants, 2 studies; very low-certainty evidence); up to 30 minutes after the procedure (MD -1.10, 95% CI -2.82 to 0.62; 12 participants, 1 study; very low-certainty evidence); and one to two hours after the procedure (MD -0.17, 95% CI -2.22 to 1.88; 12 participants, 1 study; very low-certainty evidence). No studies reported any harms. The evidence is very uncertain about the effect of opioids on episodes of apnea during (RR 3.27, 95% CI 0.85 to 12.58; 124 participants, 2 studies; very low-certainty evidence) and after the procedure (RR 2.71, 95% CI 0.11 to 64.96; 124 participants, 2 studies; very low-certainty evidence) and on hypotension (RR 1.34, 95% CI 0.32 to 5.59; 204 participants, 3 studies; very low-certainty evidence). The other main outcomes were not reported. We identified no studies comparing different opioids (e.g. morphine versus fentanyl) or different routes for administration of the same opioid (e.g. morphine enterally versus morphine intravenously).

AUTHORS' CONCLUSIONS

Compared to placebo, opioids probably reduce pain score assessed with PIPP/PIPP-R scale during the procedure; may reduce NIPS during the procedure; and may result in little to no difference in DAN one to two hours after the procedure. The evidence is very uncertain about the effect of opioids on pain assessed with other pain scores or at different time points. No studies reported if any harms occurred. The evidence is very uncertain about the effect of opioids on episodes of bradycardia or hypotension. Opioids may result in an increase in episodes of apnea. No studies reported parent satisfaction with care provided in the NICU. The evidence is very uncertain about the effect of opioids on any outcome when compared to non-pharmacological interventions or to other analgesics. We identified no studies comparing opioids to other opioids or comparing different routes of administration of the same opioid.

Systemic opioids versus other analgesics and sedatives for postoperative pain in neonates

BACKGROUND

Neonates may undergo surgery because of malformations such as diaphragmatic hernia, gastroschisis, congenital heart disease, and hypertrophic pyloric stenosis, or complications of prematurity, such as necrotizing enterocolitis, spontaneous intestinal perforation, and retinopathy of prematurity that require surgical treatment. Options for treatment of postoperative pain include opioids, non-pharmacological interventions, and other drugs. Morphine, fentanyl, and remifentanil are the opioids most often used in neonates. However, negative impact of opioids on the structure and function of the developing brain has been reported. The assessment of the effects of opioids is of utmost importance, especially for neonates in substantial pain during the postoperative period.

OBJECTIVES

To evaluate the benefits and harms of systemic opioid analgesics in neonates who underwent surgery on all-cause mortality, pain, and significant neurodevelopmental disability compared to no intervention, placebo, non-pharmacological interventions, different types of opioids, or other drugs.

SEARCH METHODS

We searched Cochrane CENTRAL, MEDLINE via PubMed and CINAHL in May 2021. We searched the WHO ICTRP, clinicaltrials.gov, and ICTRP trial registries. We searched conference proceedings, and the reference lists of retrieved articles for RCTs and quasi-RCTs.  SELECTION CRITERIA: We included randomized controlled trials (RCTs) conducted in preterm and term infants of a postmenstrual age up to 46 weeks and 0 days with postoperative pain where systemic opioids were compared to 1) placebo or no intervention; 2) non-pharmacological interventions; 3) different types of opioids; or 4) other drugs.  DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. Our primary outcomes were pain assessed with validated methods, all-cause mortality during initial hospitalization, major neurodevelopmental disability, and cognitive and educational outcomes in children more than five years old. We used the fixed-effect model with risk ratio (RR) and risk difference (RD) for dichotomous data and mean difference (MD) for continuous data. We used GRADE to assess the certainty of evidence for each outcome.

MAIN RESULTS

We included four RCTs enrolling 331 infants in four countries across different continents. Most studies considered patients undergoing large or medium surgical procedures (including major thoracic or abdominal surgery), who potentially required pain control through opioid administration after surgery. The randomized trials did not consider patients undergoing minor surgery (including inguinal hernia repair) and those individuals exposed to opioids before the beginning of the trial. Two RCTs compared opioids with placebo; one fentanyl with tramadol; and one morphine with paracetamol. No meta-analyses could be performed because the included RCTs reported no more than three outcomes within the prespecified comparisons. Certainty of the evidence was very low for all outcomes due to imprecision of the estimates (downgrade by two levels) and study limitations (downgrade by one level).  Comparison 1: opioids versus no treatment or placebo Two trials were included in this comparison, comparing either tramadol or tapentadol with placebo. No data were reported on the following critical outcomes: pain; major neurodevelopmental disability; or cognitive and educational outcomes in children more than five years old. The evidence is very uncertain about the effect of tramadol compared with placebo on all-cause mortality during initial hospitalization (RR 0.32, 95% Confidence Interval (CI) 0.01 to 7.70; RD -0.03, 95% CI -0.10 to 0.05, 71 participants, 1 study; I² = not applicable). No data were reported on: retinopathy of prematurity; or intraventricular hemorrhage.  Comparison 2: opioids versus non-pharmacological interventions No trials were included in this comparison. Comparison 3: head-to-head comparisons of different opioids One trial comparing fentanyl with tramadol was included in this comparison. No data were reported on the following critical outcomes: pain; major neurodevelopmental disability; or cognitive and educational outcomes in children more than five years old. The evidence is very uncertain about the effect of fentanyl compared with tramadol on all-cause mortality during initial hospitalization (RR 0.99, 95% CI 0.59 to 1.64; RD 0.00, 95% CI -0.13 to 0.13, 171 participants, 1 study; I² = not applicable). No data were reported on: retinopathy of prematurity; or intraventricular hemorrhage.  Comparison 4: opioids versus other analgesics and sedatives One trial comparing morphine with paracetamol was included in this comparison. The evidence is very uncertain about the effect of morphine compared with paracetamol on COMFORT pain scores (MD 0.10, 95% CI -0.85 to 1.05; 71 participants, 1 study; I² = not applicable).  No data were reported on the other critical outcomes, i.e. major neurodevelopmental disability; cognitive and educational outcomes in children more than five years old, all-cause mortality during initial hospitalization; retinopathy of prematurity; or intraventricular hemorrhage.

AUTHORS' CONCLUSIONS

Limited evidence is available on opioid administration for postoperative pain in newborn infants compared to either placebo, other opioids, or paracetamol. We are uncertain whether tramadol reduces mortality compared to placebo; none of the studies reported pain scores, major neurodevelopmental disability, cognitive and educational outcomes in children older than five years old, retinopathy of prematurity, or intraventricular hemorrhage. We are uncertain whether fentanyl reduces mortality compared to tramadol; none of the studies reported pain scores, major neurodevelopmental disability, cognitive and educational outcomes in children older than five years old, retinopathy of prematurity, or intraventricular hemorrhage. We are uncertain whether morphine reduces pain compared to paracetamol; none of the studies reported major neurodevelopmental disability, cognitive and educational outcomes in children more than five years old, all-cause mortality during initial hospitalization, retinopathy of prematurity, or intraventricular hemorrhage. We identified no studies comparing opioids versus non-pharmacological interventions.

Systemic opioid regimens for postoperative pain in neonates

BACKGROUND

Postoperative pain clinical management in neonates has always been a challenging medical issue. Worldwide, several systemic opioid regimens are available for pediatricians, neonatologists, and general practitioners to control pain in neonates undergoing surgical procedures. However, the most effective and safe regimen is still unknown in the current body of literature.

OBJECTIVES

To determine the effects of different regimens of systemic opioid analgesics in neonates submitted to surgery on all-cause mortality, pain, and significant neurodevelopmental disability. Potentially assessed regimens might include: different doses of the same opioid, different routes of administration of the same opioid, continuous infusion versus bolus administration, or 'as needed' administration versus 'as scheduled' administration.

SEARCH METHODS

Searches were conducted in June 2022 using the following databases: Cochrane Central Register of Controlled Trials [CENTRAL], PubMed, and CINAHL. Trial registration records were identified via CENTRAL and an independent search of the ISRCTN registry.

SELECTION CRITERIA

We included randomized controlled trials (RCTs), quasi-randomized, cluster-randomized, and cross-over controlled trials evaluating systemic opioid regimens' effects on postoperative pain in neonates (pre-term or full-term). We considered suitable for inclusion: I) studies evaluating different doses of the same opioid; 2) studies evaluating different routes of administration of the same opioid; 3) studies evaluating the effectiveness of continuous infusion versus bolus infusion; and 4) studies establishing an assessment of an 'as needed' administration versus 'as scheduled' administration.

DATA COLLECTION AND ANALYSIS

According to Cochrane methods, two investigators independently screened retrieved records, extracted data, and appraised the risk of bias. We stratified meta-analysis by the type of intervention: studies evaluating the use of opioids for postoperative pain in neonates through continuous infusion versus bolus infusion and studies assessing the 'as needed' administration versus 'as scheduled' administration. We used the fixed-effect model with risk ratio (RR) for dichotomous data and mean difference (MD), standardized mean difference (SMD), median, and interquartile range (IQR) for continuous data. Finally, we used the GRADEpro approach for primary outcomes to evaluate the quality of the evidence across included studies.

MAIN RESULTS

In this review, we included seven randomized controlled clinical trials (504 infants) from 1996 to 2020. We identified no studies comparing different doses of the same opioid, or different routes. The administration of continuous opioid infusion versus bolus administration of opioids was evaluated in six studies, while one study compared 'as needed' versus 'as scheduled' administration of morphine given by parents or nurses. Overall, the effectiveness of continuous infusion of opioids over bolus infusion as measured by the visual analog scale (MD 0.00, 95% confidence interval (CI) -0.23 to 0.23; 133 participants, 2 studies; I² = 0); or using the COMFORT scale (MD -0.07, 95% CI -0.89 to 0.75; 133 participants, 2 studies; I² = 0), remains unclear due to study designs' limitations, such as the unclear risk of attrition, reporting bias, and imprecision among reported results (very low certainty of the evidence).  None of the included studies reported data on other clinically important outcomes such as all-cause mortality rate during hospitalization, major neurodevelopmental disability, the incidence of severe retinopathy of prematurity or intraventricular hemorrhage, and cognitive- and educational-related outcomes.  AUTHORS' CONCLUSIONS: Limited evidence is available on continuous infusion compared to intermittent boluses of systemic opioids. We are uncertain whether continuous opioid infusion reduces pain compared with intermittent opioid boluses; none of the studies reported the other primary outcomes of this review, i.e. all-cause mortality during initial hospitalization, significant neurodevelopmental disability, or cognitive and educational outcomes among children older than five years old. Only one small study reported on morphine infusion with parent- or nurse-controlled analgesia.

Pharmacological interventions for pain and sedation management in newborn infants undergoing therapeutic hypothermia

BACKGROUND

Newborn infants affected by hypoxic-ischemic encephalopathy (HIE) undergo therapeutic hypothermia. As this treatment seems to be associated with pain, and intensive and invasive care is needed, pharmacological interventions are often used. Moreover, painful procedures in the newborn period can affect pain responses later in life, impair brain development, and possibly have a long-term negative impact on neurodevelopment and quality of life.

OBJECTIVES

To determine the effects of pharmacological interventions for pain and sedation management in newborn infants undergoing therapeutic hypothermia. Primary outcomes were analgesia and sedation, and all-cause mortality to discharge.

SEARCH METHODS

We searched CENTRAL, PubMed, CINAHL (Cumulative Index to Nursing and Allied Health Literature), and the trial register ISRCTN in August 2021. We also checked the reference lists of relevant articles to identify additional studies.

SELECTION CRITERIA

We included randomized controlled trials (RCT), quasi-RCTs and cluster-randomized trials comparing drugs used for the management of pain or sedation, or both, during therapeutic hypothermia: any opioids (e.g. morphine, fentanyl), alpha-2 agonists (e.g. clonidine, dexmedetomidine), N-Methyl-D-aspartate (NMDA) receptor antagonist (e.g. ketamine), other analgesics (e.g. paracetamol), and sedatives (e.g. benzodiazepines such as midazolam) versus another drug, placebo, no intervention, or non-pharmacological interventions.  Primary outcomes were analgesia and sedation, and all-cause mortality to discharge.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed studies identified by the search strategy for inclusion. We planned to use the GRADE approach to assess the certainty of evidence. We planned to assess the methodological quality of included trials using Cochrane Effective Practice and Organisation of Care Group (EPOC) criteria (assessing randomization, blinding, loss to follow-up, and handling of outcome data). We planned to evaluate treatment effects using a fixed-effect model with risk ratio (RR) for categorical data and mean, standard deviation (SD), and mean difference (MD) for continuous data.  MAIN RESULTS: We did not find any completed studies for inclusion. Amongst the four excluded studies, topiramate and atropine were used in two and one trial, respectively; one study used dexmedetomidine and was initially reported in 2019 to be a randomized trial. However, it was an observational study (correction in 2021). We identified one ongoing study comparing dexmedetomidine to morphine.

AUTHORS' CONCLUSIONS

We found no studies that met our inclusion criteria and hence there is no evidence to recommend or refute the use of pharmacological interventions for pain and sedation management in newborn infants undergoing therapeutic hypothermia.

Diclofenac for acute postoperative pain in children

This is a protocol for a Cochrane Review (intervention). The objectives are as follows:

To assess the efficacy and safety of diclofenac (any dose) for acute postoperative pain management in children compared with placebo, other active comparators, or diclofenac administered by either different routes (e.g. oral, rectal, etc.) or strategies (e.g. as needed versus as scheduled).