Strategies for cessation of caffeine administration in preterm infants.

BACKGROUND: Apnea and intermittent hypoxemia (IH) are common developmental disorders in infants born earlier than 37 weeks' gestation. Caffeine administration has been shown to lower the incidence of these disorders in preterm infants. Cessation of caffeine treatment is based on different post-menstrual ages (PMA) and resolution of symptoms. There is uncertainty about the best timing for caffeine discontinuation. OBJECTIVES: To evaluate the effects of early versus late discontinuation of caffeine administration in preterm infants. SEARCH METHODS: We searched CENTRAL, PubMed, Embase, and three trial registries in August 2023; we applied no date limits. We checked the references of included studies and related systematic reviews. SELECTION CRITERIA: We included randomized controlled trials (RCTs) in preterm infants born earlier than 37 weeks' gestation, up to a PMA of 44 weeks and 0 days, who received caffeine for any indication for at least seven days. We compared three different strategies for caffeine cessation: 1. at different PMAs, 2. before or after five days without symptoms, and 3. at a predetermined PMA versus at the resolution of symptoms. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. Primary outcomes were: restarting caffeine therapy, intubation within one week of treatment discontinuation, and the need for non-invasive respiratory support within one week of treatment discontinuation. Secondary outcomes were: number of episodes of apnea in the seven days after treatment discontinuation, number of infants with at least one episode of apnea in the seven days after treatment discontinuation, number of episodes of intermittent hypoxemia (IH) within seven days of treatment discontinuation, number of infants with at least one episode of IH in the seven days after of treatment discontinuation, all-cause mortality prior to hospital discharge, major neurodevelopmental disability, number of days of respiratory support after treatment discontinuation, duration of hospital stay, and cost of neonatal care. We used GRADE to assess the certainty of evidence for each outcome. MAIN RESULTS: We included three RCTs (392 preterm infants). Discontinuation of caffeine at PMA less than 35 weeks' gestation versus PMA equal to or longer than 35 weeks' gestation This comparison included one single completed RCT with 98 premature infants with a gestational age between 25 + 0 and 32 + 0 weeks at birth. All infants had discontinued caffeine treatment for five days at randomization. The infants received either an oral loading dose of caffeine citrate (20 mg/kg) at randomization followed by oral maintenance dosage (6 mg/kg/day) until 40 weeks PMA, or usual care (controls), during which caffeine was stopped before 37 weeks PMA. Early cessation of caffeine administration in preterm infants at PMA less than 35 weeks' gestation may result in an increase in the number of IH episodes in the seven days after discontinuation of treatment, compared to prolonged caffeine treatment beyond 35 weeks' gestation (mean difference [MD] 4.80, 95% confidence interval [CI] 2.21 to 7.39; 1 RCT, 98 infants; low-certainty evidence). Early cessation may result in little to no difference in all-cause mortality prior to hospital discharge compared to late discontinuation after 35 weeks PMA (risk ratio [RR] not estimable; 98 infants; low-certainty evidence). No data were available for the following outcomes: restarting caffeine therapy, intubation within one week of treatment discontinuation, need for non-invasive respiratory support within one week of treatment discontinuation, number of episodes of apnea, number of infants with at least one episode of apnea in the seven days after discontinuation of treatment, or number of infants with at least one episode of IH in the seven days after discontinuation of treatment. Discontinuation based on PMA versus resolution of symptoms This comparison included two RCTs with a total of 294 preterm infants. Discontinuing caffeine at the resolution of symptoms compared to discontinuing treatment at a predetermined PMA may result in little to no difference in all-cause mortality prior to hospital discharge (RR 1.00, 95% CI 0.14 to 7.03; 2 studies, 294 participants; low-certainty evidence), or in the number of infants with at least one episode of apnea within the seven days after discontinuing treatment (RR 0.60, 95% CI 0.31 to 1.18; 2 studies; 294 infants; low-certainty evidence). Discontinuing caffeine based on the resolution of symptoms probably results in more infants with IH in the seven days after discontinuation of treatment (RR 0.38, 95% CI 0.20 to 0.75; 1 study; 174 participants; moderate-certainty evidence). No data were available for the following outcomes: restarting caffeine therapy, intubation within one week of treatment discontinuation, need for non-invasive respiratory support within one week of treatment discontinuation, or number of episodes of IH in the seven days after treatment discontinuation. Adverse effects In the Rhein 2014 study, five of the infants randomized to caffeine had the caffeine treatment discontinued at the discretion of the clinical team, because of tachycardia. The Pradhap 2023 study reported adverse events, including recurrence of apnea of prematurity (15% in the short and 13% in the regular course caffeine therapy group), varying severities of bronchopulmonary dysplasia, hyperglycemia, extrauterine growth restriction, retinopathy of prematurity requiring laser treatment, feeding intolerance, osteopenia, and tachycardia, with no significant differences between the groups. The Prakash 2021 study reported that adverse effects of caffeine therapy for apnea of prematurity included tachycardia, feeding intolerance, and potential neurodevelopmental impacts, though most were mild and transient. We identified three ongoing studies. AUTHORS' CONCLUSIONS: There may be little or no difference in the incidence of all-cause mortality and apnea in infants who were randomized to later discontinuation of caffeine treatment. However, the number of infants with at least one episode of IH was probably reduced with later cessation. No data were found to evaluate the benefits and harms of later caffeine discontinuation for: restarting caffeine therapy, intubation within one week of treatment discontinuation, or need for non-invasive respiratory support within one week of treatment discontinuation. Further studies are needed to evaluate the short-term and long-term effects of different caffeine cessation strategies in premature infants.

Caffeine for apnea and prevention of neurodevelopmental impairment in preterm infants: systematic review and meta-analysis.

This systematic review and meta-analysis evaluated the evidence for dose and effectiveness of caffeine in preterm infants. MEDLINE, EMBASE, CINHAL Plus, CENTRAL, and trial databases were searched to July 2022 for trials randomizing preterm infants to caffeine vs. placebo/no treatment, or low (≤10 mg·kg-1) vs. high dose (>10 mg·kg-1 caffeine citrate equivalent). Two researchers extracted data and assessed risk of bias using RoB; GRADE evaluation was completed by all authors. Meta-analysis of 15 studies (3530 infants) was performed in REVMAN across four epochs: neonatal/infant (birth-1 year), early childhood (1-5 years), middle childhood (6-11 years) and adolescence (12-19 years). Caffeine reduced apnea (RR 0.59; 95%CI 0.46,0.75; very low certainty) and bronchopulmonary dysplasia (0.77; 0.69,0.86; moderate certainty), with higher doses more effective. Caffeine had no effect on neurocognitive impairment in early childhood but possible benefit on motor function in middle childhood (0.72; 0.57,0.91; moderate certainty). The optimal dose remains unknown; further long-term studies, are needed.

Brainstem depolarization-induced lethal apnea associated with gain-of-function SCN1AL263V is prevented by sodium channel blockade.

Apneic events are frightening but largely benign events that often occur in infants. Here, we report apparent life-threatening apneic events in an infant with the homozygous SCN1AL263V missense mutation, which causes familial hemiplegic migraine type 3 in heterozygous family members, in the absence of epilepsy. Observations consistent with the events in the infant were made in an Scn1aL263V knock-in mouse model, in which apnea was preceded by a large brainstem DC-shift, indicative of profound brainstem depolarization. The L263V mutation caused gain of NaV1.1 function effects in transfected HEK293 cells. Sodium channel blockade mitigated the gain-of-function characteristics, rescued lethal apnea in Scn1aL263V mice, and decreased the frequency of severe apneic events in the patient. Hence, this study shows that SCN1AL263V can cause life-threatening apneic events, which in a mouse model were caused by profound brainstem depolarization. In addition to being potentially relevant to sudden infant death syndrome pathophysiology, these data indicate that sodium channel blockers may be considered therapeutic for apneic events in patients with these and other gain-of-function SCN1A mutations.

Doxapram for apnoea of prematurity and neurodevelopmental outcomes at age 5-6 years.

OBJECTIVE: To assess the long-term neurodevelopmental impact of doxapram for treating apnoea of prematurity. DESIGN: Secondary analysis of the French national cohort study EPIPAGE-2. Recruitment took place in 2011. A standardised neurodevelopmental assessment was performed at age 5-6 years. A 2:1 propensity score matching was used to control for the non-randomised assignment of doxapram treatment. SETTING: Population-based cohort study. PATIENTS: All children born before 32 weeks' gestation alive at age 5-6 years. INTERVENTIONS: Blind and standardised assessment by trained neuropsychologists and paediatricians at age 5-6 years. MAIN OUTCOME MEASURES: Neurodevelopmental outcomes at age 5-6 years assessed by trained paediatricians and neuropsychologists: cerebral palsy, developmental coordination disorders, IQ and behavioural difficulties. A composite criterion for overall neurodevelopmental disabilities was built. RESULTS: The population consisted of 2950 children; 275 (8.6%) received doxapram. Median (IQR) gestational age was 29.4 (27.6-30.9) weeks. At age 5-6 years, complete neurodevelopmental assessment was available for 60.3% (1780 of 2950) of children and partial assessment for 10.6% (314 of 2950). In the initial sample, children receiving doxapram had evidence of greater clinical severity than those not treated. Doxapram treatment was associated with overall neurodevelopmental disabilities of any severity (OR 1.43, 95% CI 1.07 to 1.92, p=0.02). Eight hundred and twenty-one children were included in the 2:1 matched sample. In this sample, perinatal characteristics of both groups were similar and doxapram treatment was not associated with overall neurodevelopmental disabilities (OR 1.09, 95% CI 0.76 to 1.57, p=0.63). CONCLUSIONS: In children born before 32 weeks' gestation, doxapram treatment for apnoea of prematurity was not associated with neurodevelopmental disabilities.

Improving rates of successful extubation: Medications.

This chapter focuses on the pharmacological management of newborn infants in the peri-extubation period to reduce the risk of re-intubation and prolonged mechanical ventilation. Drugs used to promote respiratory drive, reduce the risk of apnoea, reduce lung inflammation and avoid bronchospasm are critically assessed. When available, Cochrane reviews and randomised trials are used as the primary sources of evidence. Methylxanthines, particularly caffeine, are well studied and there is accumulating evidence to guide clinicians on the timing and dosage that may be used. Efficacy and safety for doxapram, steroids, adrenaline and salbutamol are summarised. Management of term infants, extubation following surgery, accidental and complicated extubation and the use of cuffed endotracheal tubes are presented. Overall, caffeine is the only drug with a substantial evidence base, proven to increase the likelihood of successful extubation in preterm infants; no drugs are needed to facilitate extubation in most term infants. Future studies might further define the role of caffeine in late preterm infants and evaluate medications for post-extubation stridor, bronchospasm or apnoea not responsive to methylxanthines.

Caffeine versus other methylxanthines for the prevention and treatment of apnea in preterm infants.

BACKGROUND: Methylxanthines, including caffeine, theophylline, and aminophylline, work as stimulants of the respiratory drive, and decrease apnea of prematurity, a developmental disorder common in preterm infants. In particular, caffeine has been reported to improve important clinical outcomes, including bronchopulmonary dysplasia (BPD) and neurodevelopmental disability. However, there is uncertainty regarding the efficacy of caffeine compared to other methylxanthines. OBJECTIVES: To assess the effects of caffeine compared to aminophylline or theophylline in preterm infants at risk of apnea, with apnea, or in the peri-extubation phase. SEARCH METHODS: We searched CENTRAL, MEDLINE, Embase, Epistemonikos, the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP), and clinicaltrials.gov in February 2023. We also checked the reference lists of relevant articles to identify additional studies. SELECTION CRITERIA: Studies: randomized controlled trials (RCTs) and quasi-RCTs Participants: infants born before 34 weeks of gestation for prevention and extubation trials, and infants born before 37 weeks of gestation for treatment trials Intervention and comparison: caffeine versus theophylline or caffeine versus aminophylline. We included all doses and duration of treatment. DATA COLLECTION AND ANALYSIS: We used standard methodological procedures expected by Cochrane. We evaluated treatment effects using a fixed-effect model with risk ratio (RR), risk difference (RD), and 95% confidence intervals (CI) for categorical data, and mean, standard deviation, and mean difference for continuous data. We used the GRADE approach to evaluate the certainty of evidence. MAIN RESULTS: We included 22 trials enrolling 1776 preterm infants. The indication for treatment was prevention of apnea in three studies, treatment of apnea in 13 studies, and extubation management in three studies. In three studies, there were multiple indications for treatment, and in one study, the indication for treatment was unclear. In 19 included studies, the infants had a mean gestational age between 28 and 32 weeks and a mean birth weight between 1000 g and 1500 g. One study's participants had a mean gestational age of more than 32 weeks, and two studies had participants with a mean birth weight of 1500 g or more. Caffeine administrated for any indication may result in little to no difference in all-cause mortality prior to hospital discharge compared to other methylxanthines (RR 1.12, 95% CI 0.68 to 1.84; RD 0.02, 95% CI -0.05 to 0.08; 2 studies, 396 infants; low-certainty evidence). Only one study enrolling 79 infants reported components of the outcome moderate to severe neurodevelopmental disability at 18 to 26 months. The evidence is very uncertain about the effect of caffeine on cognitive developmental delay compared to other methylxanthines (RR 0.17, 95% CI 0.02 to 1.37; RD -0.12, 95% CI -0.24 to 0.01; 1 study, 79 infants; very low-certainty evidence). The evidence is very uncertain about the effect of caffeine on language developmental delay compared to other methylxanthines (RR 0.76, 95% CI 0.37 to 1.58; RD -0.07, 95% CI -0.27 to 0.12; 1 study, 79 infants; very low-certainty evidence). The evidence is very uncertain about the effect of caffeine on motor developmental delay compared to other methylxanthines (RR 0.50, 95% CI 0.13 to 1.96; RD -0.07, 95% CI -0.21 to 0.07; 1 study, 79 infants; very low-certainty evidence). The evidence is very uncertain about the effect of caffeine on visual and hearing impairment compared to other methylxanthines. At 24 months of age, visual impairment was seen in 8 out of 11 infants and 10 out of 11 infants in the caffeine and other methylxanthines groups, respectively. Hearing impairment was seen in 2 out of 5 infants and 1 out of 1 infant in the caffeine and other methylxanthines groups, respectively. No studies reported the outcomes cerebral palsy, gross motor disability, and mental development. Compared to other methylxanthines, caffeine may result in little to no difference in BPD/chronic lung disease, defined as 28 days of oxygen exposure at 36 weeks' postmenstrual age (RR 1.40, 95% CI 0.92 to 2.11; RD 0.04, 95% CI -0.01 to 0.09; 3 studies, 481 infants; low-certainty evidence). The evidence is very uncertain about the effect of caffeine on side effects (tachycardia, agitation, or feed intolerance) leading to a reduction in dose or withholding of methylxanthines compared to other methylxanthines (RR 0.17, 95% CI 0.02 to 1.32; RD -0.29, 95% CI -0.57 to -0.02; 1 study, 30 infants; very low-certainty evidence). Caffeine may result in little to no difference in duration of hospital stay compared to other methylxanthines (median (interquartile range): caffeine 43 days (27.5 to 61.5); other methylxanthines 39 days (28 to 55)). No studies reported the outcome seizures. AUTHORS' CONCLUSIONS: Although caffeine has been shown to improve important clinical outcomes, in the few studies that compared caffeine to other methylxanthines, there might be little to no difference in mortality, bronchopulmonary dysplasia, and duration of hospital stay. The evidence is very uncertain about the effect of caffeine compared to other methylxanthines on long-term development and side effects. Although caffeine or other methylxanthines are widely used in preterm infants, there is little direct evidence to support the choice of which methylxanthine to use. More research is needed, especially on extremely preterm infants born before 28 weeks of gestation. Data from four ongoing studies might provide more evidence on the effects of caffeine or other methylxanthines.

Methylxanthine for the prevention and treatment of apnea in preterm infants.

BACKGROUND: Very preterm infants often require respiratory support and are therefore exposed to an increased risk of chronic lung disease and later neurodevelopmental disability. Although methylxanthines are widely used to prevent and treat apnea associated with prematurity and to facilitate extubation, there is uncertainty about the benefits and harms of different types of methylxanthines. OBJECTIVES: To assess the effects of methylxanthines on the incidence of apnea, death, neurodevelopmental disability, and other longer-term outcomes in preterm infants (1) at risk for or with apnea, or (2) undergoing extubation. SEARCH METHODS: We searched CENTRAL, MEDLINE, Embase, two other databases, and three trial registers (November 2022). SELECTION CRITERIA: We included randomized trials in preterm infants, in which methylxanthines (aminophylline, caffeine, or theophylline) were compared to placebo or no treatment for any indication (i.e. prevention of apnea, treatment of apnea, or prevention of re-intubation). DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods and GRADE to assess the certainty of evidence. MAIN RESULTS: We included 18 studies (2705 infants), evaluating the use of methylxanthine in preterm infants for: any indication (one study); prevention of apnea (six studies); treatment of apnea (five studies); and to prevent re-intubation (six studies). Death or major neurodevelopmental disability (DMND) at 18 to 24 months. Only the Caffeine for Apnea of Prematurity (CAP) study (enrolling 2006 infants) reported on this outcome. Overall, caffeine probably reduced the risk of DMND in preterm infants treated with caffeine for any indication (risk ratio (RR) 0.87, 95% confidence interval (CI) 0.78 to 0.97; risk difference (RD) -0.06, 95% CI -0.10 to -0.02; number needed to treat for an additional beneficial outcome (NNTB) 16, 95% CI 10 to 50; 1 study, 1869 infants; moderate-certainty evidence). No other trials reported DMND. Results from the CAP trial regarding DMND at 18 to 24 months are less precise when analyzed based on treatment indication. Caffeine probably results in little or no difference in DMND in infants treated for prevention of apnea (RR 1.00, 95% CI 0.80 to 1.24; RD -0.00, 95% CI -0.10 to 0.09; 1 study, 423 infants; moderate-certainty evidence) and probably results in a slight reduction in DMND in infants treated for apnea of prematurity (RR 0.85, 95% CI 0.71 to 1.01; RD -0.06, 95% CI -0.13 to 0.00; NNTB 16, 95% CI 7 to > 1000; 1 study, 767 infants; moderate-certainty evidence) or to prevent re-intubation (RR 0.85, 95% CI 0.73 to 0.99; RD -0.08, 95% CI -0.15 to -0.00; NNTB 12, 95% CI 6 to >1000; 1 study, 676 infants; moderate-certainty evidence). Death. In the overall analysis of any methylxanthine treatment for any indication, methylxanthine used for any indication probably results in little or no difference in death at hospital discharge (RR 0.99, 95% CI 0.71 to 1.37; I2 = 0%; RD -0.00, 95% CI -0.02 to 0.02; I2 = 5%; 7 studies, 2289 infants; moderate-certainty evidence). Major neurodevelopmental disability at 18 to 24 months. In the CAP trial, caffeine probably reduced the risk of major neurodevelopmental disability at 18 to 24 months (RR 0.85, 95% CI 0.76 to 0.96; RD -0.06, 95% CI -0.10 to -0.02; NNTB 16, 95% CI 10 to 50; 1 study, 1869 infants; moderate-certainty evidence), including a reduction in the risk of cerebral palsy or gross motor disability (RR 0.60, 95% CI 0.41 to 0.88; RD -0.03, 95% CI -0.05 to -0.01; NNTB 33, 95% CI 20 to 100; 1 study, 1810 infants; moderate-certainty evidence) and a marginal reduction in the risk of developmental delay (RR 0.88, 95% CI 0.78 to 1.00; RD -0.05, 95% CI -0.09 to -0.00; NNTB 20, 95% CI 11 to > 1000; 1 study, 1725 infants; moderate-certainty evidence). Any apneic episodes, failed apnea reduction after two to seven days (< 50% reduction in apnea) (for infants treated with apnea), and need for positive-pressure ventilation after institution of treatment. Methylxanthine used for any indication probably reduces the occurrence of any apneic episodes (RR 0.31, 95% CI 0.18 to 0.52; I2 = 47%; RD -0.38, 95% CI -0.51 to -0.25; I2 = 49%; NNTB 3, 95% CI 2 to 4; 4 studies, 167 infants; moderate-certainty evidence), failed apnea reduction after two to seven days (RR 0.48, 95% CI 0.33 to 0.70; I2 = 0%; RD -0.31, 95% CI -0.44 to -0.17; I2 = 53%; NNTB 3, 95% CI 2 to 6; 4 studies, 174 infants; moderate-certainty evidence), and may reduce receipt of positive-pressure ventilation after institution of treatment (RR 0.61, 95% CI 0.39 to 0.96; I2 = 0%; RD -0.06, 95% CI -0.11 to -0.01; I2 = 49%; NNTB 16, 95% CI 9 to 100; 9 studies, 373 infants; low-certainty evidence). Chronic lung disease. Methylxanthine used for any indication reduces chronic lung disease (defined as the use of supplemental oxygen at 36 weeks' postmenstrual age) (RR 0.77, 95% CI 0.69 to 0.85; I2 = 0%; RD -0.10, 95% CI -0.14 to -0.06; I2 = 18%; NNTB 10, 95% CI 7 to 16; 4 studies, 2142 infants; high-certainty evidence). Failure to extubate or the need for re-intubation within one week after initiation of therapy. Methylxanthine used for the prevention of re-intubation probably results in a large reduction in failed extubation compared with no treatment (RR 0.48, 95% CI 0.32 to 0.71; I2 = 0%; RD -0.27, 95% CI -0.39 to -0.15; I2 = 69%; NNTB 4, 95% CI 2 to 6; 6 studies, 197 infants; moderate-certainty evidence). AUTHORS' CONCLUSIONS: Caffeine probably reduces the risk of death, major neurodevelopmental disability at 18 to 24 months, and the composite outcome DMND at 18 to 24 months. Administration of any methylxanthine to preterm infants for any indication probably leads to a reduction in the risk of any apneic episodes, failed apnea reduction after two to seven days, cerebral palsy, developmental delay, and may reduce receipt of positive-pressure ventilation after institution of treatment. Methylxanthine used for any indication reduces chronic lung disease (defined as the use of supplemental oxygen at 36 weeks' postmenstrual age).

Doxapram for the prevention and treatment of apnea in preterm infants.

BACKGROUND: Apnea of prematurity is a common problem in preterm infants that may have significant consequences on their development. Methylxanthines (aminophylline, theophylline, and caffeine) are effective in the treatment of apnea of prematurity. Doxapram is used as a respiratory stimulant in cases refractory to the methylxanthine treatment. OBJECTIVES: To evaluate the benefits and harms of doxapram administration on the incidence of apnea and other short-term and longer-term clinical outcomes in preterm infants. SEARCH METHODS: We used standard, extensive Cochrane search methods. The latest search date was March 2023. SELECTION CRITERIA: We included randomized controlled trials (RCTs) assessing the role of doxapram in prevention and treatment of apnea of prematurity and prevention of reintubation in preterm infants (less than 37 weeks' gestation). We included studies comparing doxapram with either placebo or methylxanthines as a control group, or when doxapram was used as an adjunct to methylxanthines and compared to methylxanthines alone as a control group. We included studies of doxapram at any dose and route. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. Our primary outcomes were clinical apnea, need for positive pressure ventilation after initiation of treatment, failed apnea reduction after two to seven days, and failed extubation (defined as unable to wean from invasive intermittent positive pressure ventilation [IPPV] and extubate or reintubation for IPPV within one week). We used GRADE to assess the certainty of evidence for each outcome. MAIN RESULTS: We included eight RCTs enrolling 248 infants. Seven studies (214 participants) provided data for meta-analysis. Five studied doxapram for treatment of apnea in preterm infants. Three studied doxapram to prevent reintubation in preterm infants. None studied doxapram in preventing apnea in preterm infants. All studies administered doxapram intravenously as continuous infusions. Two studies used doxapram as an adjunct to aminophylline compared to aminophylline alone and one study as an adjunct to caffeine compared to caffeine alone. When used to treat apnea, compared to no treatment, doxapram may result in a slight reduction in failed apnea reduction (risk ratio [RR] 0.45, 95% confidence interval [CI] 0.20 to 1.05; 1 study, 21 participants; low-certainty evidence). The evidence is very uncertain about the effect of doxapram on need for positive pressure ventilation after initiation of treatment (RR 0.31, 95% CI 0.01 to 6.74; 1 study, 21 participants; very low-certainty evidence). Doxapram may result in little to no difference in side effects causing cessation of therapy (0 events in both groups; risk difference [RD] 0.00, 95% CI -0.17 to 0.17; 1 study, 21 participants; low-certainty evidence). Compared to alternative treatment, the evidence is very uncertain about the effect of doxapram on failed apnea reduction (RR 1.35, 95% CI 0.53 to 3.45; 4 studies, 84 participants; very low-certainty evidence). The evidence is very uncertain about the effect of doxapram on need for positive pressure ventilation after initiation of treatment (RR 2.40, 95% CI 0.11 to 51.32; 2 studies, 37 participants; very-low certainty evidence; note 1 study recorded 0 events in both groups. Thus, the RR and CIs were calculated from 1 study rather than 2). Doxapram may result in little to no difference in side effects causing cessation of therapy (0 events in all groups; RD 0.00, 95% CI -0.15 to 0.15; 37 participants; 2 studies; low-certainty evidence). As adjunct therapy to methylxanthine, the evidence is very uncertain about the effect of doxapram on failed apnea reduction after two to seven days (RR 0.08, 95% CI 0.01 to 1.17; 1 study, 10 participants; very low-certainty evidence). No studies reported on clinical apnea, chronic lung disease at 36 weeks' postmenstrual age (PMA), death at any time during initial hospitalization, long-term neurodevelopmental outcomes in the three comparisons, and need for positive pressure ventilation and side effects when used as adjunct therapy to methylxanthine. In studies to prevent reintubation, when compared to alternative treatment, the evidence is very uncertain about the effect of doxapram on failed extubation (RR 0.43, 95% CI 0.10 to 1.83; 1 study, 25 participants; very low-certainty evidence). As adjunct therapy to methylxanthine, doxapram may result in a slight reduction in 'clinical apnea' after initiation of treatment (RR 0.36, 95% CI 0.13 to 0.98; 1 study, 56 participants; low-certainty evidence). Doxapram may result in little to no difference in failed extubation (RR 0.92, 95% CI 0.52 to 1.62; 1 study, 56 participants; low-certainty evidence). The evidence is very uncertain about the effect of doxapram on side effects causing cessation of therapy (RR 6.42, 95% CI 0.80 to 51.26; 2 studies, 85 participants; very low-certainty evidence). No studies reported need for positive pressure ventilation, chronic lung disease at 36 weeks' PMA, long-term neurodevelopmental outcomes in the three comparisons; failed extubation when compared to no treatment; and clinical apnea, death at any time during initial hospitalization, and side effects when compared to no treatment or alternative treatment. We identified two ongoing studies, one conducted in Germany and one in multiple centers in the Netherlands and Belgium. AUTHORS' CONCLUSIONS: In treating apnea of prematurity, doxapram may slightly reduce failure in apnea reduction when compared to no treatment and there may be little to no difference in side effects against both no treatment and alternative treatment. The evidence is very uncertain about the need for positive pressure ventilation when compared to no treatment or alternative treatment and about failed apnea reduction when used as alternative or adjunct therapy to methylxanthine. For use to prevent reintubation, doxapram may reduce apnea episodes when administered in adjunct to methylxanthine, but with little to no difference in failed extubation. The evidence is very uncertain about doxapram's effect on death when used as adjunct therapy to methylxanthine and about failed extubation when used as alternative or adjunct therapy to methylxanthine. There is a knowledge gap about the use of doxapram as a therapy to prevent apnea. More studies are needed to clarify the role of doxapram in the treatment of apnea of prematurity, addressing concerns about long-term outcomes. The ongoing studies may provide useful data.

Effects of caffeine on diaphragmatic activity in preterm infants.

BACKGROUND: Caffeine is the first-choice drug for the treatment for apnea of prematurity (AOP) in preterm infants and it has been reported that it improves the diaphragm activity. The aim of this study was to evaluate by ultrasound possible changes in diaphragm contractility and motility induced by caffeine. METHODS: We studied 26 preterm infants with gestational age ≤34 weeks treated with caffeine for the prevention or treatment of AOP. Diaphragmatic ultrasound was performed 15 min (T0 ) before and 60 min (T60 ) after the loading (20 mg/kg) or maintenance (5 mg/kg) dose of caffeine. RESULTS: Diaphragmatic excursion (DE) and thickness at the end of inspiration (DT-in) and expiration (DT-ex), as well as peak velocity of the excursion at the end of inspiration (DT-in) and expiration (DT-ex) increased after administration of both loading and maintenance dose of caffeine. CONCLUSIONS: Ultrasounds confirmed that caffeine improves the activity of diaphragm in preterm infants improving its thickness, amplitude of excursions, and contraction velocity. These results are consistent with the effectiveness of caffeine in treating AOP and decreasing the risk of failure of noninvasive respiratory support in preterm infants with respiratory distress syndrome (RDS).

Pharmacokinetics of intravenous propofol in southern white rhinoceros (Ceratotherium simum simum) after intramuscular etorphine-butorphanol-medetomidine-azaperone.

OBJECTIVE: To determine the pharmacokinetics of a single bolus of intravenous (IV) propofol after intramuscular administration of etorphine, butorphanol, medetomidine, and azaperone in 5 southern white rhinoceros to facilitate reproductive evaluations. A specific consideration was whether propofol would facilitate timely orotracheal intubation. ANIMALS: 5 adult, female, zoo-maintained southern white rhinoceros. PROCEDURES: Rhinoceros were administered etorphine (0.002 mg/kg), butorphanol (0.02 to 0.026 mg/kg), medetomidine (0.023 to 0.025 mg/kg), and azaperone (0.014 to 0.017 mg/kg) intramuscularly (IM) prior to an IV dose of propofol (0.5 mg/kg). Physiologic parameters (heart rate, blood pressure, respiratory rate, and capnography), timed parameters (eg, time to initial effects and intubation), and quality of induction and intubation were recorded following drug administration. Venous blood was collected for analysis of plasma propofol concentrations using liquid chromatography-tandem mass spectrometry at various time points after propofol administration. RESULTS: All animals were approachable following IM drug administration, and orotracheal intubation was achieved at 9.8 ± 2.0 minutes (mean ±SD) following propofol administration. The mean clearance for propofol was 14.2 ± 7.7 ml/min/kg, the mean terminal half-life was 82.4 ± 74.4 minutes, and the maximum concentration occurred at 2.8 ± 2.9 minutes. Two of 5 rhinoceros experienced apnea after propofol administration. Initial hypertension, which improved without intervention, was observed. CLINICAL RELEVANCE: This study provides pharmacokinetic data and insight into the effects of propofol in rhinoceros anesthetized using etorphine, butorphanol, medetomidine, and azaperone. While apnea was observed in 2 rhinoceros, propofol administration allowed for rapid control of the airway and facilitated oxygen administration and ventilatory support.

Enteral and Parenteral Treatment with Caffeine for Preterm Infants in the Delivery Room: A Randomised Trial.

BACKGROUND: Early treatment with caffeine in the delivery room (DR) has been proposed to decrease the need for mechanical ventilation (MV) by limiting episodes of apnoea and improving respiratory mechanics in preterm infants. Our aim was to verify the hypothesis that intravenous or enteral administration of caffeine can be performed in the preterm infant in the DR. METHODS: Infants with 25±0-29±6 weeks of gestational age were enrolled and randomised to receive 20 mg/kg of caffeine citrate intravenously, via the umbilical vein, or enterally, through an orogastric tube, within 10 min of birth. Caffeine blood level was measured at 60 ± 15 min after administration and 60 ± 15 min before the next dose (5 mg/kg). The primary endpoint was evaluation of the success rate of intravenous and enteral administration of caffeine in the DR. RESULTS: Nineteen patients were treated with intravenous caffeine and 19 with enteral caffeine. In all patients the procedure was successfully performed. Peak blood level of caffeine 60 ± 15 min after administration in the DR was found to be below the therapeutic range (5 µg/mL) in 25 % of samples and above the therapeutic range in 3%. Blood level of caffeine 60 ± 15 min before administration of the second dose was found to be below the therapeutic range in 18% of samples. CONCLUSIONS: Intravenous and enteral administration of caffeine can be performed in the DR without interfering with infants' postnatal assistance. Some patients did not reach the therapeutic range, raising the question of which dose is the most effective to prevent MV. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT04044976; EudraCT number 2018-003626-91.

Standardizing Prostaglandin Initiation in Prenatally Diagnosed Ductal-Dependent Neonates; A Quality Initiative.

Prostaglandin E1 (PGE) is used in patients with ductal-dependent congenital heart disease (CHD). Side effects of apnea and fever are often dose dependent and occur within 48 h after initiation. We initiated a standardized approach to PGE initiation after our institution recognized a high incidence of side effects and a wide variety of starting doses of PGE. Neonates with prenatally diagnosed ductal-dependent CHD were identified, started on a standardized protocol that started PGE at 0.01 mcg/kg/min, and evaluated for PGE related side effects. Compliance, outcomes and dose adjustments during the first 48 h post-PGE initiation were evaluated. Fifty patients were identified (25 pre-intervention; 25 post-intervention). After intervention, compliance with the protocol was 96%, and apnea or fever occurred in 28% (compared to 63% pre-intervention, p = 0.015). Dose adjustments (either increase or decrease) prior to cardiac surgery were similar in both cohorts (60%, 52%, p = 0.569). There were no mortalities or emergent procedures performed due to ductus arteriosus closure. Standardizing a protocol for initiating PGE in prenatally diagnosed ductal-dependent CHD was successful and reduced the incidence of apnea, fever, and sepsis evaluations. A starting dose of 0.01 mcg/kg/min did not cause increased adverse effects.

Evaluation of pharmaceutically compounded oral caffeine on the impact of medication adherence and risk of readmission among preterm neonates: A single-center quasi-experimental study.

BACKGROUND: Caffeine is available in an ampoule, used via parenteral and enteral routes in preterm neonates to treat apnea of prematurity (AOP) in neonates of gestational age ≥ 35-40 weeks. A longer duration of therapy has a higher risk of medication non-adherence due to higher costs and inappropriate dosage forms. Pharmaceutically compounded oral caffeine (PCC) could be an appropriate alternate dosage form. The researchers aimed to determine the impact of PCC on medication-related factors influencing medication adherence (MA) and the frequency of hospital readmission with apnea (HRA) in preterm neonates. METHODS: We conducted a single-center quasi-experimental study for this quality improvement project using PCC among the preterm neonates admitted in a tertiary care level-III NICU at the Aga Khan University Hospital Karachi, Pakistan, received caffeine therapy, and survived at discharge. The researchers compared pre-PCC data (April-December 2017) with post-PCC data (April-Dec 2018) each for nine months, with three months intervals (January-March 2018) of PCC formulation and implementation phase. The study was conducted according to the SQUIRE2.0 guidelines. The Data were collated on factors influencing MA, including the cost of therapy, medication refill rates, and parental complaints as primary outcome measures. The Risk factors of HRA were included as secondary outcomes. RESULTS: After PCC implementation cost of therapy was reduced significantly from Rs. 97000.0 (729.0 USD) to Rs. 24500.0 (185.0 USD) (p<0.001), significantly higher (p<0.001) number of patients completed remaining refills (77.6% pre-phase vs 97.5% post-phase). The number of parental complaints about cost, ampoule usage, medication drawing issue, wastage, inappropriate dosage form, and longer duration of therapy reduced significantly in post-phase. HRA reduced from 25% to 6.6% (p<0.001). Post-implementation of PCC (RR 0.14; 95% CI: 0.07-0.27) was a significant independent risk factor for reducing HRA using a multivariate analysis model. Longer duration of caffeine therapy after discharge (RR 1.05; 95% CI: 1.04-1.04), those who were born in multiple births (RR 1.15; 95% CI: 1.15-1.15), and those who had higher number of siblings were other significant independent risk factors for HRA. CONCLUSIONS: PCC dispensation in the appropriate dosage form at discharge effectively reduced cost, non-adherence to therapy, and risk of hospital readmissions. This neonatal clinical and compounding pharmacist-led model can be replicated in other resource-limiting setting.

The association of salivary caffeine levels with serum concentrations in premature infants with apnea of prematurity.

The purpose of this paper is to verify whether the concentrations of caffeine in saliva are comparable to serum concentrations in preterm infants who are treated with caffeine for apnea of prematurity. This is a prospective observational study. Eligible participants were newborn infants < 37 weeks of gestational age treated with oral or intravenous caffeine for apnea of prematurity. Two paired samples of saliva and blood were collected per patient. Tube solid-phase microextraction coupled online to capillary liquid chromatography with diode array detection was used for analysis. A total of 47 infants with a median gestational age of 28 [26-30] weeks and a mean of 1.11 ± 0.4 kg of birth weight. Median postmenstrual age, when samples were collected, was 31 [29-33] weeks. Serum caffeine median levels of 19.30 µg/mL [1.9-53.90] and salivary caffeine median levels of 16.36 µg/mL [2.20-56.90] were obtained. There was a strong positive Pearson's correlation between the two variables r = 0.83 (p < 0.001). CONCLUSION: The measurement of salivary caffeine concentrations after intravenous or oral administration offers an alternative to serum caffeine monitoring in apnea of prematurity. Measurement of salivary concentration minimizes blood draws, improves blood conservation, and subsequently minimizes painful procedures in premature infants. WHAT IS KNOWN: • Salivary sampling may be useful when is applied to extremely low birth weight infant, in whom blood sampling must be severely restricted. WHAT IS NEW: • The measurement of caffeine salivary concentrations after intravenous or oral administration offers an alternative to serum caffeine monitoring in apnoea of prematurity. • Salivary sampling may be a valid non-invasive alternative that could be used to individualize and optimize caffeine dose.

Comparative efficacy and safety of caffeine citrate and aminophylline in treating apnea of prematurity: A systematic review and meta-analysis.

BACKGROUND: Methylxanthine, including caffeine citrate and aminophylline, is the most common pharmacologic treatment for apnea of prematurity. However, due to the lack of high-quality evidence, there are no clear recommendations or guidelines on how to choose between caffeine and aminophylline. OBJECTIVE: This meta-analysis aimed to assess the comparative efficacy and safety of caffeine and aminophylline for apnea of prematurity, and provide reliable evidence for clinical medication in the treatment for apnea of prematurity. METHODS: PubMed, Scopus, Embase, EBSCO, Web of Science, and Cochrane databases were systematically searched from May 1975 to June 2022. RESULTS: Ten studies including a total of 923 preterm infants were evaluated. Our results showed that there was no significant difference in the effective rate of 1-3days between caffeine and aminophylline (OR 1.05, 95%CI: 0.40-2.74, P = 0.914). However, for side effects such as tachycardia (OR 0.22, 95%CI: 0.13-0.37, P<0.001) and feeding intolerance (OR 0.40, 95%CI: 0.23-0.70, P = 0.001), the incidence rate was lower in the caffeine group compared with the aminophylline group. No significant difference was found in hyperglycemia (OR 0.45, 95%CI: 0.19-1.05, P = 0.064). CONCLUSION: This meta-analysis reveals that caffeine citrate and aminophylline have similar therapeutic effectiveness on respiratory function, but caffeine has fewer side effects and should be considered first for treatment.

Population pharmacokinetic modeling of caffeine in preterm infants with apnea of prematurity: New findings from concomitant erythromycin and AHR genetic polymorphisms.

Current standard-dose caffeine therapy results in significant intersubject variability. The aims of this study were to develop and evaluate population pharmacokinetic (PPK) models of caffeine in preterm infants through comprehensive screening of covariates and then to propose model-informed precision dosing of caffeine for this population. A total of 129 caffeine concentrations from 96 premature neonates were incorporated into this study. Comprehensive medical record and genotype data of these neonates were collected for analysis. PPK modeling was performed by a nonlinear mixed effects modeling program (NONMEM). Final models based on the current weight (CW) or body surface area (BSA) were evaluated via multiple graphic and statistical methods. The model-informed dosing regimen was performed through Monte Carlo simulations. In addition to CW or BSA, postnatal age, coadministration with erythromycin (ERY), and aryl hydrocarbon receptor coding gene (AHR) variant (rs2158041) were incorporated into the final PPK models. Multiple evaluation results showed satisfactory prediction performance and stability of the CW- and BSA-based models. Monte Carlo simulations demonstrated that trough concentrations of caffeine in preterm infants would be affected by concomitant ERY therapy and rs2158041 under varying dose regimens. For the first time, ERY and rs2158041 were found to be associated with the clearance of caffeine in premature infants. Similar predictive performance and stability were obtained for both CW- and BSA-based PPK models. These findings provide novel insights into caffeine precision therapy for preterm infants.

Effectiveness and safety of early versus late caffeine therapy in managing apnoea of prematurity among preterm infants: a retrospective cohort study.

BACKGROUND: Early administration of intravenous (IV) caffeine (initiation within 2 days of life) is an effective treatment strategy for the management of apnoea of prematurity among infants. However, the safety and effectiveness of early administration of oral caffeine treatment is not be fully established. AIM: We aimed to compare the effectiveness and safety of early versus late caffeine therapy on preterm infants' clinical outcomes. METHOD: A retrospective matched cohort study was conducted using data of patients admitted to neonatal intensive care units of two tertiary care hospitals between January 2016 and December 2018. The clinical outcomes and mortality risk between early caffeine (initiation within 2 days of life) and late caffeine (initiation ≥ 3 days of life) were compared. RESULTS: Ninety-five pairs matched based on gestational age were included in the study. Compared to late initiation, preterm infants with early caffeine therapy had: a shorter duration of non-invasive mechanical ventilation (median 5 days vs. 12 days; p < 0.001); shorter length of hospital stay (median 26 days vs. 44 days; p < 0.001); shorter duration to achieve full enteral feeding (median 5 days vs. 11 days; p < 0.001); and lower frequency of bronchopulmonary dysplasia (BPD) (4.5% vs. 12.9%; p = 0.045). They also had a reduced risk of osteopenia of prematurity (OP) (OR 0.209; 95% CI 0.085-0.509; p = 0.001). CONCLUSION: Early oral caffeine therapy can potentially improve respiratory outcomes among infants with apnoea of prematurity. However, an increase in mortality associated with early caffeine therapy requires further investigation.