Caffeine citrate - Is it a silver bullet in neonatology?

Temporal effects of caffeine on intrapulmonary shunt in preterm ventilated infants

OBJECTIVES

We hypothesized that caffeine would be associated with a transient reduction in the right-to-left shunt and VA/Q. We aimed to explore the temporal effects of caffeine on right-to-left shunt, ventilation perfusion ratio (VA/Q) and shift of the oxyhaemoglobin dissociation curve (ODC) in premature ventilated infants.

METHODS

Retrospective cohort study at a tertiary neonatal unit of infants born at less than 31 weeks of gestation that were mechanically ventilated on day three of life. The non-invasive method of the ODC was used to determine the right-to-left shunt, VA/Q and shift before and at 1, 4 and 20 h after a maintenance dose of caffeine citrate.

RESULTS

A total of 21 infants were included with a median (range) gestational age of 27 (23.7-30.7) weeks. The median shunt percentage was significantly reduced, compared to baseline at 1 h (8 (range: 7-9) % vs. 4 (range: 0-6) %, p=0.042) and 4 h post caffeine administration (8 (range: 7-9) % vs. 0 (range: 0-3) %, p=0.042), but the VA/Q and the right shift of the ODC did not differ significantly between these time points. At 20 h, there were no significant differences between these indices compared to baseline values.

CONCLUSIONS

Caffeine led to a transient decrease in intrapulmonary shunt from one to 4 h after administration and this may be due to its diuretic action.

Predictors for poor daily weight gain in preterm neonates exposed to different dose regimens of caffeine in ICU- a retrospective cohort study

BACKGROUND

With a wide therapeutic index, efficacy, ease of use, and other neuroprotective and respiratory benefits, caffeine citrate(CC) is currently the drug of choice for preterm neonates (PTNs). Caffeine-induced excessive energy expenditure, diuresis, natriuresis, and other CC-associated potential side-effects (CC-APSEs) result in lower daily-weight gain (WG) in premature neonates. This study aimed to evaluate the risk factors for daily-WG in neonates exposed to different dose regimens of caffeine in ICU.

METHOD

This retrospective cohort study included neonates of ≤ 36weeks gestational age (GA) and received CC-therapy. The same participants were followed for data analysis in two postnatal phases: 15-28 and 29-42 days of life (DOL). Based on daily CC-dose, formed group-I (received; standard-doses = 5 mg/kg/day), group-II (received;>5-7 mg/kg/day), and group-III (received;>7 mg/kg/day). Prenatal and postnatal clinical characteristics, CC-regimen, daily-WG, CC-APSEs, and concomitant risk-factors, including daily-caloric intake, Parenteral-Nutrition duration, steroids, diuretics, and ibuprofen exposure, were analyzed separately for group-II and group-III using group-I as standard. Regression analysis was performed to evaluate the risk factors for daily-WG.

RESULTS

Included 314 PTNs. During 15-28 DOL, the mean-daily-WG(MD-WG) was significantly higher in group-I than group-II [19.9 ± 0.70 g/kg/d vs. 17.7 ± 0.52 p = 0.036] and group-III [19.9 ± 0.70 g/kg/d vs. 16.8 ± 0.73 p < 0.001]. During 29-42 DOL the MD-WG of group-I was only significantly higher than group-III [21.7 ± 0.44 g/kg/d vs. 18.3 ± 0.41 g/kg/d p = 0.003] and comparable with group-II. During 15-28 DOL, observed CC-APSEs was significantly higher in group-II and III but during 29-42 DOL it was only significant in group-III. In the adjusted regression analysis for daily-WG during 15-28DOL, with respect to standard-dose, 5-7 mg/kg/day (β=-1.04; 95%CI:-1.62,-0.93) and > 7-10 mg/kg/day (β=-1.36; 95%CI:-1.56,-1.02) were associated with a lower daily-WG. However, during 29-42DOL, this association was present only for > 7-10 mg/kg/day (β=-1.54; 95%CI:-1.66,-1.42). The GA ≤ 27weeks (β=-1.03 95%CI:-1.24, -0.88) was associated with lower daily-WG only during 15-28DOL. During both periods of therapy, higher cumulative-caffeine dose and presence of culture proven sepsis, tachypnea, hyponatremia, and feeding intolerance were significantly associated with lower daily-WG. Conversely, daily kcal intake was found to be linked with an increase in daily-WG in both periods.

CONCLUSION

In this study cohort exposure to higher caffeine daily and cumulative doses is associated with lower postnatal daily-WG in PTNs than standard-daily doses, which may be due to its catabolic effects and CC-APSEs.

Gastrointestinal effects of caffeine in preterm infants: a systematic review and Bayesian meta-analysis

OBJECTIVE

Caffeine is widely used in preterm infants to prevent or treat apnoea of prematurity. Adverse gastrointestinal effects of caffeine have not been thoroughly researched in preterm infants. With this systematic review and meta-analysis, we aim to summarise the results of trials on the gastrointestinal effects of caffeine in preterm infants.

DESIGN

We searched MEDLINE, Web of Science, Scopus and ClinicalTrials.gov up to 21 April 2023. We included randomised controlled trials assessing caffeine versus placebo in preterm neonates and reporting gastrointestinal side effects. Risk of bias was assessed using the Cochrane Risk of Bias tool. A Bayesian meta-analysis was performed to estimate the pooled OR of gastrointestinal side effects.

RESULTS

Nine trials involving 2746 preterm infants were analysed. Seven trials assessing necrotising enterocolitis and four trials assessing feeding intolerance in our meta-analysis found no differences between caffeine and placebo (OR=1.007 (95% credible interval 0.021, 5.462), I2=97.4%, and OR=1.266 (95% credible interval 0.064, 28.326), I2=84.8%, respectively). Four trials assessed the outcomes spontaneous intestinal perforation, constipation, gastrointestinal disorder (composite outcome: gastro-oesophageal regurgitation or dilated bowel loops), age at oral feeding and cholestasis syndrome and found no differences between groups. One trial assessed the outcomes gastro-oesophageal symptoms and duration of tube feeding and found that caffeine was associated with a reduced burden of gastro-oesophageal reflux symptoms at 2 weeks (p<0.05), but not at term.

CONCLUSIONS

According to this systematic review and meta-analysis, the use of caffeine at usual doses in preterm infants does not seem to be associated with significant gastrointestinal adverse effects.

Dose-Response Study of Caffeine on Postnatal Weight Gain in Premature Neonates-A Retrospective Cohort Study

Background

Caffeine citrate (CC)-induced excessive energy expenditure, diuresis, natriuresis, and other CC-associated potential side effects (CC-APSEs) result in lower daily weight gain (WG) in premature neonates. This study aimed to assess higher CC-doses' effect on the mean daily-WG (MD-WG) and CC-APSE development, considering 5 mg/kg/day as the standard regimen.

Method

This retrospective cohort study included neonates of ≤36 weeks gestational age and received CC-therapy. The same participants were followed for data analysis in two postnatal phases: 15-28 and 29-42 days of life (DOL). Based on daily CC-dose, formed group-I=(5 mg/kg/day), group-II=(>5-7 mg/kg/day), and group-III=(>7 mg/kg/day). Data was analyzed separately for group-II and group-III using group-I as the standard.

Results

The study included 284 neonates. During phase-I, the MD-WG was significantly higher in group-I than group-II (19.9 ± .88 g/kg/d vs 17.5 ± .49, P = .031) and group-III (19.9 ± .88 g/kg/d vs 16.7 ± .71, P < .001). During 29-42 DOL, the MD-WG of group-I was only significantly higher than group-III (21.5 ± .42 g/kg/d vs 18.1 ± .39 g/kg/d, P = .003) and comparable with group-II. During 15-28 DOL, CC-APSEs were significantly higher in group-II and group-III but during 29-42 DOL was significant only in group-III.

Conclusion

Exposure to higher caffeine doses in this study cohort is associated with lower postnatal WG in preterm neonates than standard daily doses may be due to its catabolic effects and CC-APSEs.

Caffeine intake and its association with nutrition, sleep, and physical activity among schoolchildren in the United Arab Emirates: a national cross-sectional study

PURPOSE

Recent surveys indicate a significant increase in total caffeine intake among schoolchildren. Limited research has been published concerning the total intake of caffeine among schoolchildren in the Middle East and Gulf Cooperation Council (GCC) countries, including the UAE.

METHODS

This cross-sectional survey estimated the total caffeine intake from foods and beverages among 10,275 schoolchildren in the UAE. Caffeine intakes were related to the European Food Safety Authority's level of no safety concern (3.0 mg/kg BW) and level of effects on sleep (1.4 mg/kg BW).

RESULTS

More than half (56.2%) of the students consumed more than 100 mg (the upper limit allowed) of caffeine from dietary sources. High intake of caffeine (> 100 mg/day) was significantly associated (p = 0.001) with reduced sleep duration, difficulty falling asleep, infrequent exercising, using smart devices for more than 2 h a day, getting a lower GPA, skipping breakfast, eating fewer servings of vegetables than recommended, frequent consumption of fast food and more frequent snack consumption.

CONCLUSION

Excessive intake of caffeine from different dietary sources coexists with unhealthy dietary and lifestyle behaviors and sleep problems. Tailoring educational programs and intervention strategies is warranted to correct the unhealthy intake of caffeine and the associated unhealthy dietary and lifestyle behaviors among schoolchildren in the UAE.

Current therapeutic targets and multifaceted physiological impacts of caffeine

Caffeine, which shares consubstantial structural similarity with purine adenosine, has been demonstrated as a nonselective adenosine receptor antagonist for eliciting most of the biological functions at physiologically relevant dosages. Accumulating evidence supports caffeine's beneficial effects against different disorders, such as total cardiovascular diseases and type 2 diabetes. Conversely, paradoxical effects are also linked to caffeine ingestion in humans including hypertension-hypotension and tachycardia-bradycardia. These observations suggest the association of caffeine action with its ingested concentration and/or concurrent interaction with preferential molecular targets to direct explicit events in the human body. Thus, a coherent analysis of the functional targets of caffeine, relevant to normal physiology, and disease pathophysiology, is required to understand the pharmacology of caffeine. This review provides a broad overview of the experimentally validated targets of caffeine, particularly those of therapeutic interest, and the impacts of caffeine on organ-specific physiology and pathophysiology. Overall, the available empirical and epidemiological evidence supports the dose-dependent functional activities of caffeine and advocates for further studies to get insights into the caffeine-induced changes under specific conditions, such as asthma, DNA repair, and cancer, in view of its therapeutic applications.

Drugs targeting adenosine signaling pathways: A current view

Adenosine is an endogenous nucleoside that regulates many physiological and pathological processes. It is derived from either the intracellular or extracellular dephosphorylation of adenosine triphosphate and interacts with cell-surface G-protein-coupled receptors. Adenosine plays a substantial role in protecting against cell damage in areas of increased tissue metabolism and preventing organ dysfunction in pathological states. Targeting adenosine metabolism and receptor signaling may be an effective therapeutic approach for human diseases, including cardiovascular and central nervous system disorders, rheumatoid arthritis, asthma, renal diseases, and cancer. Several lines of evidence have shown that many drugs exert their beneficial effects by modulating adenosine signaling pathways but this knowledge urgently needs to be summarized, and most importantly, actualized. The present review collects pharmaceuticals and pharmacological or diagnostic tools that target adenosine signaling in their primary or secondary mode of action. We overviewed FDA-approved drugs as well as those currently being studied in clinical trials. Among them are already used in clinic A2A adenosine receptor modulators like istradefylline or regadenoson, but also plenty of anti-platelet, anti-inflammatory, or immunosuppressive, and anti-cancer drugs. On the other hand, we investigated dozens of specific adenosine pathway regulators that are tested in clinical trials to treat human infectious and noninfectious diseases. In conclusion, targeting purinergic signaling represents a great therapeutic challenge. The actual knowledge of the involvement of adenosinergic signaling as part of the mechanism of action of old drugs has open a path not only for drug-repurposing but also for new therapeutic strategies.

The Effect of Caffeine on Heart Rate Variability in Newborns: A Pilot Study

Neonatal apnoea can be treated with caffeine, which affects the central nervous and cardiovascular systems. Heart rate variability (HRV) reflects the activity of the autonomic nervous system (ANS) and might be used as a measure of ANS maturation in newborns. We aimed to establish the effect of caffeine on HRV in newborns and investigated the potential correlation between HRV and postmenstrual age (PMA). In 25 haemodynamically stable newborns hospitalized due to apnoea and treated with caffeine (2.5 mg/kg), we assessed breathing frequency, arterial oxygen saturation, body temperature, and the heart rate while they were sleeping. We assessed HRV by spectral analysis using fast Fourier transformation. The same protocol was reapplied 100 h after caffeine withdrawal to assess the control parameters. Caffeine increased breathing frequency (p = 0.023) but did not affect any other parameter assessed including HRV. We established a positive correlation between postmenstrual age and HRV during treatment with caffeine as well as after caffeine had been withdrawn (total power: p = 0.044; low-frequency band: p = 0.039). Apparently, the maintenance dose of caffeine is too low to affect the heart rate and HRV. A positive correlation between PMA and HRV might reflect maturation of the ANS, irrespective of caffeine treatment.

Preparation and Evaluation of Caffeine Orodispersible Films: The Influence of Hydrotropic Substances and Film-Forming Agent Concentration on Film Properties

This study aimed to develop caffeine (CAF) orodispersible films (ODFs) and verify the effects of different percentages of film-forming agent and hydrotropic substances (citric acid-CA or sodium benzoate-SB) on various film properties. Hydroxypropyl methylcellulose E 5 (HPMC E 5) orodispersible films were prepared using the solvent casting method. Four CAF-ODF formulations were prepared and coded as CAF1 (8% HPMC E 5, CAF), CAF2 (8% HPMC E 5 and CAF:CA-1:1), CAF3 (9% HPMC E 5 and CAF:CA-1:1), and CAF4 (9% HPMC E 5 and CAF:SB-1:1). The CAF-ODFs were evaluated in terms of disintegration time, folding endurance, thickness, uniformity of mass, CAF content, thickness-normalized tensile strength, adhesiveness, dissolution, and pH. Thin, opaque, and slightly white CAF-ODFs were obtained. All the formulations developed exhibited disintegration times less than 3 min. The dissolution test revealed that CAF1, CAF2, and CAF3 exhibited concentrations of active pharmaceutical ingredients (APIs) released at 30 min that were close to 100%, whilst CAF4 showed a faster dissolution behaviour (100% of the CAF was released at 5 min). Thin polymeric films containing 10 mg of CAF/surface area (3.14 cm²) were prepared.

Relationship between caffeine intake and small for gestational age and preterm birth: a dose-response meta-analysis

Our meta-analysis aimed to determine the dose-response relationship between caffeine intake and risk of small for gestational age (SGA) and preterm birth (PB). A systematic search of PubMed, Web of science and Scopus was done from inception to January 2023 using relevant keywords. All case-control and cohort studies reported in English were included if the exposure of interest was caffeine intake during pregnancy, the outcome of interest was spontaneous SGA and PB, and multivariable-adjusted odds ratios (ORs) or risk ratios were provided or could be calculated. In all, 22 studies (15 cohort studies and seven case-control studies) were included in this review. Examining the association of caffeine intake with risk of PB, no significant relationship was found (Pooled ES: 1.04; 95% CI: 0.95 to 1.14, P = 0.019). Findings from this meta-analysis demonstrated that caffeine intake had a significantly higher risk of SGA respectively (Pooled ES: 1.28; 95% CI: 1.16 to 1.41, P < 0.001). A dose-response analysis proposed that an increase of 100 mg caffeine per day was associated with a 13% greater risk of SGA. This study confirmed that caffeine intake raises the risk of SGA. However, the risk of PB was not found to be reliably associated with maternal caffeine consumption.

Determination of caffeine, paraxanthine, theophylline and theobromine in premature infants by HILIC-MS/MS

Aim: Caffeine is a central nervous system stimulant, used to treat apnea of prematurity. A hydrophilic interaction chromatography-tandem mass spectrometry (HILIC-MS/MS) approach was developed to detect caffeine, paraxanthine, theophylline and theobromine in premature infants. Method: Protein precipitation of plasma samples (10 μl) was carried out by treating with acetonitrile containing caffeine-¹³C₃. The separation was carried out on an ACQUITY HPLC^® BEH HILIC column. Caffeine and its metabolites were quantified by multiple reaction monitoring modes with positive electrospray ionization. Results: The established method had a good linear relationship in the range of 0.0600-60.0 μg/ml for caffeine, 0.0250-7.50 μg/ml for theobromine and 0.0150-4.50 μg/ml for paraxanthine and theophylline. Conclusion: A HILIC-MS/MS method was developed and validated to determine caffeine and its major metabolites in plasma of premature infants.

Probing Caffeine Administration as a Medical Management for Hydrocephalus: An Experimental Study

BACKGROUND

Hydrocephalus is currently managed by cerebrospinal fluid diversion from the cerebral ventricles to other body sites, but this is complicated by obstruction and infection in young infants, thus adding to morbidity and mortality. Studies have reported caffeine to be a pleiotropic neuroprotective drug in the developing brain due to its antioxidant, anti-inflammatory, and antiapoptotic properties, with improved white matter microstructural development. In this study, we investigate the use of caffeine administration as a possible means of pharmacological management for hydrocephalus.

METHODS

A total of 76 three-day-old mice pups from 10 dams were divided into four groups: hydrocephalus was induced in the pups in two groups by intracisternal injection of kaolin suspension, and their dams were given either caffeine (50 mg/kg by gavage) or water daily for 21 days; the dams in the other 2 (non-hydrocephalic) groups similarly had either caffeine or water; the pups received caffeine administered via lactation. Developmental neurobehavioral tests were performed until day 21, when the pups were sacrificed. Their brains were removed and processed for Cresyl and Golgi staining; both quantitative and qualitative analyses were then carried out.

RESULTS

Improved developmental motor activities and reflexes were observed in the hydrocephalus + caffeine-treated pups. Caffeine administration was associated with reduced cell death and increased dendritic arborization of the neurons in the sensorimotor cortex and striatum of hydrocephalic mice pups.

CONCLUSION

Caffeine administration appears to have promise as an adjunct in hydrocephalus management, and its use needs to be further explored.

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.

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.

Therapeutic drug monitoring of caffeine and its primary metabolites in plasma using LC-ESI-MS/MS for apnea of prematurity treatment: Evaluation of ultrapure water as a surrogate matrix

The growing evidence has endorsed the view that therapeutic drug monitoring (TDM) of caffeine for apnea of prematurity is helpful for dose tailoring when the therapeutic response is lacking or toxicity is suspected. However, the plasma without caffeine is difficult to obtain. Therefore, a method was developed and validated to measure caffeine and its three primary metabolites (paraxanthine, theobromine, and theophylline) using LC-ESI-MS/MS in human plasma and several surrogate matrices. The chromatographic separation of analytes was finally achieved on a Waters Symmetry C18 (4.6 × 75 mm, 3.5 μm) column. Several strategies were successfully applied to overcome the matrix effects: 1) appropriate dilution for sample cleanup; 2) a starting lower proportion of organic phase; 3) multiple individual stable-labeled isotopic internal standards. The parallelism between the authentic matrix and surrogate matrices was convincing. The recovery of the analytes in both human plasma and rat plasma was acceptable over the linear range (0.500 to 50.0 μg/mL for caffeine, and 0.0100 to 1.00 μg/mL for three metabolites). The method was successfully applied in 118 samples from 74 preterm infants with apnea of prematurity. The rat plasma or ultrapure water as surrogate matrix is worthy of being recommended for routine TDM of caffeine.

Caffeine treatment started before injury reduces hypoxic-ischemic white-matter damage in neonatal rats by regulating phenotypic microglia polarization

BACKGROUND

Reducing neuroinflammatory damage is an effective strategy for treating white-matter damage (WMD) in premature infants. Caffeine can ameliorate hypoxia-ischemia-induced brain WMD; however, its neuroprotective effect and mechanism against hypoxic-ischemic WMD remain unclear.

METHODS

We used 3-day-old Sprague-Dawley rats to establish a model of cerebral hypoxia-ischemia-induced brain WMD after unilateral common carotid artery ligation and hypoxia exposure (8% O₂ + 92% N₂) for 2.5 h. Mechanism experiments were conducted to detect M1/M2 polarization and activation of microglia and NLRP3 inflammasome.

RESULTS

Caffeine inhibited NLRP3 inflammasome activation, reduced microglial Iba-1 activation, inhibited microglia M1 polarization, and promoted microglia M2 polarization by downregulating CD86 and iNOS protein expression, inhibiting the transcription of the proinflammatory TNF-α and IL-1β, upregulating CD206 and Arg-1 expression, and promoting the transcription of the anti-inflammatory factors IL-10 and TGF-β. Importantly, we found that these caffeine-mediated effects could be reversed after inhibiting A2aR activity.

CONCLUSIONS

Caffeine improved long-term cognitive function in neonatal rats with hypoxic-ischemic WMD via A2aR-mediated inhibition of NLRP3 inflammasome activation, reduction of microglial activation, regulation of the phenotypic polarization of microglia and the release of inflammatory factors, and improvement of myelination development.

IMPACT

The direct protective effect of caffeine on hypoxic-ischemic white-matter damage (WMD) and its mechanism remains unclear. This study elucidated this mechanism using neonatal rats as an animal model of hypoxia-ischemia-induced cerebral WMD. The findings demonstrated caffeine as a promising therapeutic tool against immature WMD to protect neonatal cognitive function. We found that caffeine pretreatment reduced WMD in immature brains via regulation of microglial activation and polarization by adenosine A2a receptor, thereby, providing a scientific basis for future clinical application of caffeine.

Caffeine citrate for apnea of prematurity-One dose does not fit all a prospective study

BACKGROUND

Caffeine citrate is the most frequently used medication in preterm neonates for the prevention of apnea of prematurity. There is no accepted consensus regarding the optimal caffeine citrate dosing. In this study, we evaluate clinical responses of premature neonates to standard-dose caffeine citrate treatment.

METHODS

A prospective observational study conducted at the NICU at Sheba Medical Center (3/2016-2/2017). The study population included preterm neonates born at a gestational age (GA) < 33 weeks and treated with caffeine citrate according to the local NICU protocol.

RESULTS

The study cohort included 66 preterm neonates of GA < 33 weeks. Thirty infants were defined as responders and 36 as nonresponders to 7.5 mg/kg caffeine citrate treatment, and they required a further dose increase to 10 mg/kg. Infants in the nonresponders group were born at earlier GA than responders (29 vs. 31 weeks, respectively, P = 0.004). The nonresponders required a significantly longer hospital stay (56 vs. 46 days, P = 0.014), and longer supplemental oxygen support (18 vs 2 days, P = 0.008).

CONCLUSIONS

Caffeine citrate initiation at higher doses is safe and does not require routine serum levels monitoring. It might be more effective for controlling apnea of prematurity in preterm neonates born ≤29 weeks of gestation.

Effects of Caffeine on Splanchnic Oxygenation in Preterm Infants

OBJECTIVE

The aim of this study is to assess the effects of administering 20 mg/kg loading dose of caffeine citrate intravenously on splanchnic oxygenation in preterm infants.

STUDY DESIGN

The infants with a gestational age (GA) of <34 weeks who were administered with a 20 mg/kg intravenous loading dose of caffeine citrate within 48 hours after birth were investigated prospectively. Regional splanchnic oxygen saturation (rsSO₂) and splanchnic fractional tissue oxygen extraction rate (sFTOE) were measured using near-infrared spectroscopy before caffeine infusion, immediately after caffeine infusion and 1, 2, 3, 4, and 6 hours (h) after dose completion; postdose values were compared with predose values.

RESULTS

A total of 41 infants with a mean GA of 29.2 ± 1.6 weeks and birth weight of 1,315 ± 257 g as well as postnatal age of 32.2 ± 10.8 hours were included in the study. rsSO₂ significantly reduced from 63.1 to 57.5% immediately after caffeine infusion, 55.1% after 1 hour, and 55.2% after 2 hours with partial recovery at 3-hour postdose. sFTOE increased correspondingly.

CONCLUSION

Caffeine reduces splanchnic oxygenation and increases splanchnic oxygen extraction for at least 2 hours with partial recovery to predose levels at 3-hour postdose.

Caffeine for the Pharmacological Treatment of Apnea of Prematurity in the NICU: Dose Selection Conundrum, Therapeutic Drug Monitoring and Genetic Factors

Caffeine citrate is the drug of choice for the pharmacological treatment of apnea of prematurity. Factors such as maturity and genetic variation contribute to the interindividual variability in the clinical response to caffeine therapy in preterm infants, making the optimal dose administered controversial. Moreover, the necessity for therapeutic drug monitoring (TDM) of caffeine is still worth discussing due to the need to achieve the desired target concentrations as well as concerns about the safety of higher doses. Therefore, we reviewed the pharmacokinetic profile of caffeine in preterm infants, evidence of the safety and efficacy of different doses of caffeine, therapeutic concentration ranges of caffeine and impact of genetic variability on caffeine therapy. Whereas the safety and efficacy of standard-dose caffeine have been demonstrated, evidence for the safety of higher administered doses is insufficient. Thus, preterm infants who lack clinical response to standard-dose caffeine therapy are of interest for TDM when dose optimization is performed. Polymorphisms in pharmacodynamics-related genes, but not in pharmacokinetics-related genes, have a significant impact on the interindividual variability in clinical response to caffeine therapy. For preterm infants lacking clinical response, how to develop individualized medication regimens for caffeine remains to be explored.

Maternal caffeine consumption and pregnancy outcomes: a narrative review with implications for advice to mothers and mothers-to-be

OBJECTIVES

Caffeine is a habit-forming substance consumed daily by the majority of pregnant women. Accordingly, it is important that women receive sound evidence-based advice about potential caffeine-related harm. This narrative review examines evidence of association between maternal caffeine consumption and negative pregnancy outcomes, and assesses whether current health advice concerning maternal caffeine consumption is soundly based.

METHODS

Database searches using terms linking caffeine and caffeinated beverages to pregnancy outcomes identified 1261 English language peer-reviewed articles. Screening yielded a total of 48 original observational studies and meta-analyses of maternal caffeine consumption published in the past two decades. The articles reported results for one or more of six major categories of negative pregnancy outcomes: miscarriage, stillbirth, low birth weight and/or small for gestational age, preterm birth, childhood acute leukaemia, and childhood overweight and obesity.

RESULTS

Of 42 separate sets of findings reported in 37 observational studies, 32 indicated significantly increased caffeine-related risk and 10 suggested no or inconclusive associations. Caffeine-related increased risk was reported with moderate to high levels of consistency for all pregnancy outcomes except preterm birth. Of 11 studies reporting 17 meta-analyses, there was unanimity among 14 analyses in finding maternal caffeine consumption to be associated with increased risk for the four outcome categories of miscarriage, stillbirth, low birth weight and/or small for gestational age, and childhood acute leukaemia. The three remaining meta-analyses were also unanimous in reporting absence of a reliable association between maternal caffeine consumption and preterm birth. No meta-analyses were identified for childhood overweight and obesity, although four of five original observational studies reported significant associations linking maternal caffeine consumption to that outcome category.

CONCLUSIONS

The substantial majority finding from observational studies and meta-analyses is that maternal caffeine consumption is reliably associated with major negative pregnancy outcomes. Reported findings were robust to threats from potential confounding and misclassification. Among both observational studies and meta-analyses, there were frequent reports of significant dose-response associations suggestive of causation, and frequent reports of no threshold of consumption below which associations were absent. Consequently, current evidence does not support health advice that assumes 'moderate' caffeine consumption during pregnancy is safe. On the contrary, the cumulative scientific evidence supports pregnant women and women contemplating pregnancy being advised to avoid caffeine.

Caffeine disrupts ataxia telangiectasia mutated gene-related pathways and exacerbates acetaminophen toxicity in human fetal immortalized hepatocytes

Preterm infants are at greater risk for adverse drug effects due to hepatic immaturity. Multiple interventions during intensive care increases potential for drug interactions. In this setting, high-dose caffeine used for apnea in premature infants may increase acetaminophen toxicity by inhibiting ataxia telangiectasia mutated (ATM) gene activity during DNA damage response. To define caffeine and acetaminophen interaction, we modeled infantile prematurity in late-gestation fetal stage through human immortalized hepatocytes and liver organoids. The acute toxicity studies included assays for cell viability, mitochondrial dysfunction and ATM pathway-related DNA damage. Fetal cells expressed hepatobiliary properties, albeit with lower metabolic, synthetic and antioxidant functions than more mature hepatocytes. Acetaminophen in IC50 amount of 7.5 millimolar caused significant oxidative stress, mitochondrial membrane potential impairments, and DNA breaks requiring ATM-dependent repair. Caffeine markedly exacerbated acetaminophen toxicity by suppressing ATM activity in otherwise nontoxic 2.5 millimolar amount. Similarly, the specific ATM kinase antagonist, KU-60019, reproduced this deleterious interaction in 5 micromolar amount. Replicative stress from combined acetaminophen and caffeine toxicity depleted cells undergoing DNA synthesis in S phase and activated checkpoints for G0/G1 or G2/M restrictions. Synergistic caffeine and acetaminophen toxicity in liver organoids indicated these consequences should apply in vivo. The antioxidant, N-acetylcysteine, decreased oxidative damage, mitochondrial dysfunction and ATM pathway disruption to mitigate caffeine and acetaminophen toxicity. We concluded that hepatic DNA damage, mitochondrial impairment and growth-arrest after combined caffeine and acetaminophen toxicity will be harmful for premature infants. Whether caffeine and acetaminophen toxicity may alter outcomes in subsequently encountered hepatic disease needs consideration.

Therapy for Apnoea of Prematurity: A Retrospective Study on Effects of Standard Dose and Genetic Variability on Clinical Response to Caffeine Citrate in Chinese Preterm Infants

INTRODUCTION

Apnoea of prematurity (AOP) is among the most common diagnoses in the neonatal intensive care unit. Caffeine treatment is a preferred treatment choice. However, neonatal caffeine therapy results in significant intersubject variability. This study aimed to determine the effects of plasma caffeine levels based on standard dose and genetic variability on clinical response to caffeine citrate in Chinese preterm infants.

METHODS

This single-center and retrospective study examined data from 112 preterm infants (< 35 weeks gestational age) between July 2017 and July 2018. Subjects were divided into apnoea-free (n = 48) and apnoeic (n = 64) groups, and their clinical outcomes were summarized. Liquid chromatography-tandem mass spectrometry was used to measure levels of caffeine and its primary metabolites. Eighty-eight single-nucleotide polymorphisms were chosen for genotyping by a MassARRAY system.

RESULTS

Preterm infants in the apnoea-free group were associated with a reduction in the incidence of bronchopulmonary dysplasia and a reduced requirement for patent ductus arteriosus ligation. No significant association was observed between plasma-trough-concentration-to-dose (C₀/D) ratio and birth weight, gestational age, or postnatal age in either group. Polymorphisms in CYP1A2 and aryl hydrocarbon receptor (AHR) genes did not affect plasma caffeine levels. Polymorphisms in adenosine receptor genes ADORA1 (rs10920568 and rs12744240), ADORA2A (rs34923252 and rs5996696), and ADORA3 (rs10776727 and rs2298191), especially in AHR (rs4410790) and adenosine deaminase (rs521704), play critical roles in the interindividual response to caffeine therapy.

CONCLUSIONS

Genetic polymorphisms in caffeine's target receptors, but not the exposure levels based on the standard dosing, were associated with variable responses to caffeine therapy in preterm neonates. Future studies are needed to uncover how these genetic variants affect responses to caffeine therapy in this patient population.

Encephalopathy in Preterm Infants: Advances in Neuroprotection With Caffeine

With the improvement in neonatal rescue technology, the survival rate of critically ill preterm infants has substantially increased; however, the incidence of brain injury and sequelae in surviving preterm infants has concomitantly increased. Although the etiology and pathogenesis of preterm brain injury, and its prevention and treatment have been investigated in recent years, powerful and effective neuroprotective strategies are lacking. Caffeine is an emerging neuroprotective drug, and its benefits have been widely recognized; however, its effects depend on the dose of caffeine administered, the neurodevelopmental stage at the time of administration, and the duration of exposure. The main mechanisms of caffeine involve adenosine receptor antagonism, phosphodiesterase inhibition, calcium ion activation, and γ-aminobutyric acid receptor antagonism. Studies have shown that there are both direct and indirect beneficial effects of caffeine on the immature brain. Accordingly, this article briefly reviews the pharmacological characteristics of caffeine, its mechanism of action in the context of encephalopathy in premature infants, and its use in the neuroprotection of encephalopathy in this patient population.

[Comparison of the efficacy of domestic and imported caffeine citrate in the treatment of apnea in preterm infants: a prospective randomized double-blind controlled trial]

OBJECTIVE

To compare the efficacy of domestic and imported caffeine citrate in the treatment of apnea in preterm infants.

METHODS

A total of 98 preterm infants with a gestational age of 28 - <34 weeks between April 2018 and December 2019 were enrolled. They were randomly administered with domestic (n=48) or imported caffeine citrate (n=50) within 6 hours after birth. The therapeutic effects, complications, adverse effects and clinical outcomes were compared between the two groups.

RESULTS

There were no significant differences in the incidence of apnea within 7 days after birth, daily frequency of apnea, the time of apnea disappearance, the failure rate of intubation-surfactant-extubation strategy, the time of non-invasive assisted ventilation, the duration of oxygen therapy, the duration of caffeine citrate therapy, the length of hospital stay, blood gas analysis results, liver and kidney function testing results between the two groups (P>0.05). There were no significant differences in the incidence of complications and the mortality rate between the two groups (P>0.05). There was no significant difference in the incidence of adverse effects between the two groups (P>0.05).

CONCLUSIONS

The efficacy and safety of domestic caffeine citrate in the treatment of apnea are similar to those of imported caffeine citrate in preterm infants.

Caffeine and Gastric Emptying Time in Very Preterm Neonates

Background: Caffeine has been commonly used for prevention and treatment of apnea-related symptoms in premature infants. However, its side effects have not been thoroughly studied. We investigated whether caffeine affects gastric motility in very-preterm (VP) neonates. Methods: The study is a randomized crossover clinical trial. Twenty-two neonates with mean birth weight (BW) (standard deviation—SD) 1077 (229) g and mean gestational age (GA) (SD) 28.6 (2.1) weeks were recruited. Each neonate had its gastric emptying time checked twice with ultrasound assessment of changes in antral cross sectional area (ACSA). All neonates were sequentially allocated to the caffeine group (A) and the control group (B). Complications from the gastrointestinal tract were documented throughout the study. Results: Statistically significant difference was found with regards to the gastric emptying time [median, (range)] between caffeine and control group (p = 0.040). Additionally, in the neonates with BW 1000–1500 g and GA ≥ 28 weeks, the gastric emptying time (minutes) was significantly longer during caffeine treatment [44.5 (36–68.2)] and [40 (34.5–66.5)] respectively, as compared to the gastric emptying time during no caffeine treatment [27 (24.2–30)] (p = 0.002) and [27 (24.5–30)] (p = 0.001). The incidence of gastrointestinal (GI) complications was significantly greater in neonates receiving caffeine [6 (27.%)] as compared with those without caffeine treatment [1 (4.6%)] (p = 0.039). Conclusions: During caffeine treatment, a significantly delayed gastric emptying time was noted in all study neonates, especially in these with BW 1000–1500 g and those with GA ≥ 28 weeks. Further larger studies are necessary in order to confirm this interesting finding.

Extraction-Free, Direct Determination of Caffeine in Microliter Volumes of Beverages by Thermal Desorption-Gas Chromatography Mass Spectrometry

An extraction-free method requiring microliter (μL) volumes has been developed for the determination of caffeine in beverages. Using a pyrolysis-gas chromatography mass spectrometry system, the conditions required for the direct thermal desorption-gas chromatography mass spectrometry (TD-GC/MS) determination of caffeine were optimised. A 5 μL aliquot was introduced to the thermal desorption unit, dried, and thermally desorbed to the GC/MS. The response was linear over the range 10 to 500 μg/mL (R² = 0.996). The theoretical limit of detection (3 σ) was 0.456 μg/mL. No interferences were recorded from endogenous beverage components or from commonly occurring drugs, such as nicotine, ibuprofen, and paracetamol. Replicate caffeine determinations on fortified latte style white coffee and Pepsi Max® gave mean recoveries of 93.4% (%CV = 4.1%) and 95.0% (%CV = 0.98%), respectively. Good agreement was also obtained with the stated values of caffeine for an energy drink and for Coca-Cola®. These data suggest that the method holds promise for the determination of caffeine in such samples.

Caffeine Consumption in Children: Innocuous or Deleterious? A Systematic Review

Caffeine is the most consumed psychostimulant worldwide. Its use among children is controversial. Although it produces an increase in brain activity, it could hamper growth and development in young consumers. Therefore, the aim of this review was to recognize changes produced by caffeine in children under 12 years of age and to identify the relevant alterations and the conditions of their occurrence. A systematic review of the literature was carried out using PRISMA. Initially, 5468 articles were found from the EBSCO, ScienceDirect, PubMed, and Clarivate Analytics databases. In this review, were retained 24 published articles that met the inclusion criteria. The results obtained showed that caffeine consumption hampers children's growth and development. In contrast, it supports the activation of the central nervous system and brain energy management.

Caffeine in preterm infants: where are we in 2020?

The incidence of preterm birth is increasing, leading to a growing population with potential long-term pulmonary complications. Apnoea of prematurity (AOP) is one of the major challenges when treating preterm infants; it can lead to respiratory failure and the need for mechanical ventilation. Ventilating preterm infants can be associated with severe negative pulmonary and extrapulmonary outcomes, such as bronchopulmonary dysplasia (BPD), severe neurological impairment and death. Therefore, international guidelines favour non-invasive respiratory support. Strategies to improve the success rate of non-invasive ventilation in preterm infants include pharmacological treatment of AOP. Among the different pharmacological options, caffeine citrate is the current drug of choice. Caffeine is effective in reducing AOP and mechanical ventilation and enhances extubation success; it decreases the risk of BPD; and is associated with improved cognitive outcome at 2 years of age, and pulmonary function up to 11 years of age. The commonly prescribed dose (20 mg·kg⁻¹ loading dose, 5–10 mg·kg⁻¹ per day maintenance dose) is considered safe and effective. However, to date there is no commonly agreed standardised protocol on the optimal dosing and timing of caffeine therapy. Furthermore, despite the wide pharmacological safety profile of caffeine, the role of therapeutic drug monitoring in caffeine-treated preterm infants is still debated. This state-of-the-art review summarises the current knowledge of caff­eine therapy in preterm infants and highlights some of the unresolved questions of AOP. We speculate that with increased understanding of caffeine and its metabolism, a more refined respiratory management of preterm infants is feasible, leading to an overall improvement in patient outcome.

Caffeine is the current drug of choice to prevent and treat apnoea of prematurity. There is no agreed protocol on the optimal timing and dosage of caffeine therapy for preterm babies. Data on caffeine metabolism may optimise individualised therapy.http://bit.ly/2LMuJPY

Electrical activity of the diaphragm following a loading dose of caffeine citrate in ventilated preterm infants

BACKGROUND

Administration of caffeine citrate can facilitate extubation. Our aim was to determine whether a loading dose of caffeine citrate given to ventilated, preterm infants affected the diaphragm electrical activity.

METHODS

Infants <34 weeks of gestational age were recruited if requiring mechanical ventilation and prescribed a loading dose of caffeine citrate. Surface electrodes recorded the electrical activity of the diaphragm (dEMG) before and after administration of intravenous caffeine citrate. The mean amplitude of the EMG (dEMG) trace and the mean area under the EMG curve (aEMGc) were calculated.

RESULTS

Thirty-two infants were assessed with a median gestational age of 29 (27-31) weeks. The dEMG amplitude increased, peaking at 25 min post administration (p = 0.006), and the increase in aEMGc (p = 0.004) peaked at 30 min; the differences were not significant after 60 min. At 20 min, there was an increase in minute volume (p = 0.034) and a reduction in the peak inspiratory pressure (p = 0.049).

CONCLUSIONS

We have demonstrated a transient increase in both electrical activity of the diaphragm and respiratory function following an intravenous loading dose of caffeine citrate.

Variations in preterm stabilisation practices and caffeine therapy between two European tertiary level neonatal units

AIM

To investigate interinstitutional differences in preterm infant stabilisation between two European tertiary neonatal centres with particular focus on intubation timing, surfactant administration, caffeine therapy and neonatal morbidity and mortality.

METHODS

Retrospective (2012-2014) study of very low birth weight (VLBW) preterm infants admitted to John Radcliffe Hospital (UK centre) and Charité Medical Centre (German centre). Timing of intubation, surfactant and caffeine administration and respiratory outcomes were examined.

RESULTS

Gestational age, birth weight and five-minute Apgar scores of VLBW infants from the UK centre (n = 86) were comparable to those from the German centre (n = 96). Significant differences in antenatal steroid therapy, intubation timing and surfactant therapy were noted. Timing of caffeine initiation differed significantly between centres (median 0 [0-2.5] UK vs. 2 [1.5-4] days German centre); however, caffeine was discontinued at a similar corrected gestational age of 34.7 weeks. Mechanical ventilation was significantly longer at the UK centre, but there was no difference in bronchopulmonary dysplasia (BPD) (44% UK vs. 36% German centre) or mortality (15% UK vs. 13% German centre).

CONCLUSION

Timing of primary intubation and caffeine therapy differed significantly between centres. However, earlier intubation and caffeine administration in the UK centre were not associated with a changed incidence of BPD.

Early high-dose caffeine citrate for extremely preterm infants: Neonatal and neurodevelopmental outcomes

AIM

To examine neonatal morbidities, including the incidence of cerebellar haemorrhage (CBH), and neurodevelopmental outcomes following the administration of high loading dose caffeine citrate compared to standard loading dose caffeine citrate.

METHODS

This was a retrospective study of 218 preterm infants <28 weeks' gestation who received a loading dose of caffeine citrate within the first 36 h of life at the Mater Mothers' Hospital over a 3-year period (2011-2013). Two groups were compared, with 158 neonates in the high-dose cohort receiving a median dose of caffeine citrate of 80 mg/kg and 60 neonates in the standard dose cohort receiving a median dose of 20 mg/kg. Routine cranial ultrasound, including mastoid views, was performed during the neonatal period. At 2 years of age, infants presented for follow-up and were assessed with the Neurosensory Motor Developmental Assessment (NSMDA) and the Bayley Scales of Infant and Toddler Development-III (Bayley-III).

RESULTS

There was no difference in the incidence of neonatal morbidities, including CBH, between the two groups. The incidence of CBH in the high-dose group was 2.5% compared to 1.7% in the standard-dose group. There was no difference in the neurodevelopmental follow-up scores as evaluated with the NSMDA and the Bayley-III.

CONCLUSIONS

The use of early high loading dose caffeine citrate in extremely preterm infants was not shown to be associated with CBH or abnormal long-term neurodevelopmental outcomes. The overall incidence of CBH, however, was much lower than in studies using magnetic resonance imaging techniques. It is suggested that a large randomised clinical trial is needed to determine the optimal dose of caffeine citrate when given early to very preterm infants.

The Purinome and the preBötzinger Complex - A Ménage of Unexplored Mechanisms That May Modulate/Shape the Hypoxic Ventilatory Response

Exploration of purinergic signaling in brainstem homeostatic control processes is challenging the traditional view that the biphasic hypoxic ventilatory response, which comprises a rapid initial increase in breathing followed by a slower secondary depression, reflects the interaction between peripheral chemoreceptor-mediated excitation and central inhibition. While controversial, accumulating evidence supports that in addition to peripheral excitation, interactions between central excitatory and inhibitory purinergic mechanisms shape this key homeostatic reflex. The objective of this review is to present our working model of how purinergic signaling modulates the glutamatergic inspiratory synapse in the preBötzinger Complex (key site of inspiratory rhythm generation) to shape the hypoxic ventilatory response. It is based on the perspective that has emerged from decades of analysis of glutamatergic synapses in the hippocampus, where the actions of extracellular ATP are determined by a complex signaling system, the purinome. The purinome involves not only the actions of ATP and adenosine at P2 and P1 receptors, respectively, but diverse families of enzymes and transporters that collectively determine the rate of ATP degradation, adenosine accumulation and adenosine clearance. We summarize current knowledge of the roles played by these different purinergic elements in the hypoxic ventilatory response, often drawing on examples from other brain regions, and look ahead to many unanswered questions and remaining challenges.

Antioxidative effects of caffeine in a hyperoxia-based rat model of bronchopulmonary dysplasia

Background

While additional oxygen supply is often required for the survival of very premature infants in intensive care, this also brings an increasing risk of progressive lung diseases and poor long-term lung outcomes. Caffeine is administered to neonates in neonatal intensive care for the prevention and treatment of apneas and has been shown to reduce BPD incidence and the need for mechanical ventilation, although it is still unclear whether this is due to a direct pulmonary action via antagonism of adenosine receptors and/or an indirect action. This experimental study aims to investigate the action of caffeine on the oxidative stress response in pulmonary tissue in a hyperoxia-based model of bronchopulmonary dysplasia in newborn rats.

Methods

Newborn Wistar rats were exposed to 21% or 80% oxygen for 3 (P3) or 5 (P5) postnatal days with or without recovery on room air until postnatal day 15 (P15) and treated with vehicle or caffeine (10 mg/kg) every 48 h beginning on the day of birth. The lung tissue of the rat pups was examined for oxidative stress response at P3 and P5 immediately after oxygen exposure or after recovery in ambient air (P15) by immunohistological staining and analysis of lung homogenates by ELISA and qPCR.

Results

Lungs of newborn rats, corresponding to the saccular stage of lung development and to the human lung developmental stage of preterms, showed increased rates of total glutathione and hydrogen peroxide, oxidative damage to DNA and lipids, and induction of second-phase mediators of antioxidative stress response (superoxide dismutase, heme oxygenase-1, and the Nrf2/Keap1 system) in response to hyperoxia. Caffeine reduced oxidative DNA damage and had a protective interference with the oxidative stress response.

Conclusion

In addition to the pharmacological antagonism of adenosine receptors, caffeine appears to be a potent antioxidant and modulates the hyperoxia-induced pulmonary oxidative stress response and thus protective properties in the BPD-associated animal model. Free-radical-induced damage caused by oxidative stress seems to be a biological mechanism progress of newborn diseases. New aspects of antioxidative therapeutic strategies to passivate oxidative stress-related injury should be in focus of further investigations.

Electronic supplementary material

The online version of this article (10.1186/s12931-019-1063-5) contains supplementary material, which is available to authorized users.

Comparison of Caffeine versus Theophylline for apnea of prematurity

Objective:

To make a comparison between standard doses of theophylline and caffeine for the treatment of apnea of prematurity.

Methods:

A randomised control trail was conducted in Department of Pediatrics Medicine Govt. Khawaja Muhammad Safdar Medical College and Govt. Allama Iqbal Memorial Teaching Hospital, Sialkot over duration of one year from August 2017 to August 2018 after approval from the hospital ethics committee. An informed consent in the form of written document was also taken from the parents of each infant participating in the study. Data was analyzed by using SPSS version 24. Mean and SD was calculated for numerical data like gestational age and mean concentration of caffeine and theophylline. Frequency and percentages were calculated for categorical data like nasal continuous positive airway pressure (CPAP), supplemental oxyen and intrventricular hemorrhage (IVH) grade I. Student t-test was applied in order to determine the significance of results. P value ≤ 0.05 was considered significant.

Results:

A total of 100 infants were enrolled in this study. This study was further divided into two equal groups by lottery method i.e. 50% in each, treated with Theophylline and Caffeine respectively. Mean apnea events/day in neonates administrated by theophylline was 1±0.1, 2±0.12, 2±1.1, 1±0.10 and 2±o.12 for 0, 1-3, 4-7, 8-14 and 15-21 days respectively. While, the mean apnea events/day in neonates administrated by Caffeine was 2±0.3, 1±0.22, 2±1.5, 1±0.13 and 2±0.14 for 0, 1-3, 4-7, 8-14 and 15-21 days respectively. The differences were statistically significant for 1-3 days and 4-7 days p<0.05 according to student t test.

Conclusion:

Results of our study revealed that caffeine being more effective than Theophylline for treating apnea of prematurity.

Efficacy and Safety of Different Maintenance Doses of Caffeine Citrate for Treatment of Apnea in Premature Infants: A Systematic Review and Meta-Analysis

Background

Caffeine is widely used for the treatment of neonatal apnea, but there is no agreement on the optimum maintenance dose for preterm infants.

Objective

The aims of this meta-analysis were to compare the efficacy and safety of high versus low maintenance doses of caffeine citrate for the treatment of apnea in premature infants.

Methods

Literature searches were conducted using PubMed, Cochrane Library, OVID, Embase, Web of Science, Chinese Biomedical Literature, Weipu Journal, Wanfang, and CNKI databases up to September 2018. Only randomized controlled trials (RCTs) of caffeine citrate for apnea treatment in premature infants were included. Trials were divided into those testing high maintenance doses (10-20 mg/kg daily) and low maintenance doses (5-10 mg/kg daily) for comparison. Data collection and extraction, quality assessment, and data analyses were performed according to the Cochrane standards.

Results

Among the 345 studies initially identified, thirteen RCTs involving 1515 patients were included. Compared to the low-dose group, the high-dose group exhibited greater effective treatment rate (RR: 1.37, 95%CI: 1.18 to 1.60, P<0.0001) and success rate for ventilator removal (RR: 1.74, 95%CI: 1.04 to 2.90, P=0.03), but higher incidence of tachycardia (RR: 2.02, 5%CI: 1.30 to 3.12, P=0.002). The high-dose group also demonstrated lower extubation failure rate (RR: 0.5, 95%CI: 0.35 to 0.71, P=0.0001), frequency of apnea (WMD: -1.55, 95%CI: -2.72 to -0.39, P=0.009), apnea duration (WMD: -4.85, 95%CI: -8.29 to -1.40, P=0.006), and incidence of bronchopulmonary dysplasia (RR: 0.79, 95%CI: 0.68 to 0.91, P=0.002). There were no significant group differences in other adverse events including in-hospital death (P>0.05).

Conclusions

Higher maintenance doses of caffeine citrate appear more effective and safer than low maintenance doses for treatment of premature apnea, despite a higher incidence of tachycardia.

Caffeine Treatment for Apnea of Prematurity and the Influence on Dose-Dependent Postnatal Weight Gain Observed Over 15 Years

Background and Aim: To analyze the influence on weight gain of infants exposed to two dosage regimens of oral caffeine citrate (CC) for apnea of prematurity.

Methods: Retrospective descriptive observational study of an eligible very low birth weight cohort over a 15-year period in an Irish University hospital. Data were analyzed between two distinct postnatal ages: 14–28 and 29–56 days.

Results: During the 15-year study, 457 infants were prescribed caffeine. Among the 14–28-day group, after applying exclusion criteria, 418 infants qualified. Two hundred forty-eight infants received 5 mg/(kg·day) and 170 received 10 mg/(kg·day) of CC. Among the 29–56-day group, 362 infants were identified and after applying exclusions, 332 fulfilled entry criteria [214 on 5 mg/(kg·day) and 118 on 10 mg/(kg·day) regimen]. Baseline characteristics of infants were comparable between groups without statistically significant differences. Mean daily weight gain (MDWG) in grams from day 14 to 28 showed a higher rate of increase for the 5 mg/(kg·day) group compared with the 10 mg/(kg·day) group (17.2 ± 12 g vs. 13.0 ± 10.2 g [p = 0.04]). From day 29 to 56, also MDWG was higher among infants on 5 mg/(kg·day) of CC compared with 10 mg/(kg·day) group (15.6 ± 10.8 g vs. 10.2 ± 9.8 g [p = 0.011]).

Conclusion: While a variety of measures are optimized to promote postnatal weight gain of premature infants close to an ideal intrauterine growth curve, not paying sufficient attention to one of the most widely used catabolic agents in neonatology is questionable and warrants vigilance. Additional nutritional measures could be offered to those with prolonged caffeine exposure.