Summary Introduction Rebound pain after peripheral nerve block is recognised increasingly as a postoperative complication that may diminish the benefits of regional anaesthesia. We undertook a systematic review and network meta‐analysis to evaluate pharmacological strategies for its prevention. Methods We searched relevant databases for randomised controlled trials in adults undergoing surgery with peripheral nerve blocks. The primary outcome was the incidence of rebound pain. Secondary outcomes were: timing and severity of rebound pain; time to first rescue analgesia; patient satisfaction; sleep disturbance; and intervention‐related adverse effects. Results Twenty‐four randomised controlled trials (2130 patients, eight interventions) were included. Intravenous dexamethasone had the highest probability of reducing rebound pain incidence (surface under the cumulative ranking curve 0.91) and was judged ‘definitely superior’ to control. Perineural dexamethasone and perineural dexmedetomidine ranked highest for delaying rebound pain and prolonging time to first rescue analgesia. Pre‐emptive opioids were probably inferior to control. Certainty of evidence ranged from very low to moderate. Data for pain severity, patient satisfaction and sleep disturbance were reported inconsistently and could not be pooled. Discussion Intravenous dexamethasone was the most effective intervention for preventing rebound pain following single‐injection peripheral nerve blocks. Perineural dexamethasone and dexmedetomidine showed benefit in delaying onset and prolonging analgesia. These findings support intravenous dexamethasone as a first‐line prophylactic drug, while highlighting the need for adequately powered trials of alternative strategies.

BACKGROUND:Long COVID-19 affects approximately 10-30% of individuals who are infected with SARS-CoV-2 and is associated with persistent functional impairment and reduced quality of life. The heterogeneous, multisystemic nature and nonspecific symptomatology of long COVID-19 makes its treatment challenging. This scoping review evaluates existing evidence on sympathetic and parasympathetic ganglion blocks as potential interventions for patients suffering from long COVID-19. OBJECTIVE:Our primary objective was to assess the effectiveness of sympathetic and parasympathetic ganglion blocks in treating patients with long COVID-19 by identifying the most commonly reported symptoms, symptom response to different block regimens, and any adverse effects associated with these interventions. STUDY DESIGN:A scoping review. SETTING:Outpatient clinics where patients received sympathetic blocks or parasympathetic blocks. METHODS:A comprehensive search was conducted across PubMed, Embase, Cochrane CENTRAL, Web of Science, Google Scholar, and ClinicalTrials.gov using MeSH and free-text terms related to "long COVID-19," "post-COVID-19 syndrome," and "sympathetic ganglion blocks" and "parasympathetic blocks." Only English-language articles were included. Pre-print repositories and reference lists were also manually screened. RESULTS:A total of 22 articles covering 505 patients were included in this review. The most frequently studied symptoms were olfactory dysfunction, fatigue, headache, and cognitive disturbances. The most commonly utilized intervention was the stellate ganglion block. The available evidence suggests that the stellate ganglion block could be an effective treatment for dysautonomia symptoms and cognitive dysfunction related to long COVID-19. Sphenopalatine ganglion block may be an effective option to treat headaches in long COVID-19 patients who are refractory to other treatments. LIMITATIONS:The significant existing variations in treatment regimens precluded our ability to do a quantitative analysis. Reporting bias from case reports and small observational studies should also be considered. CONCLUSIONS:Stellate ganglion blocks may offer therapeutic benefit for the dysautonomia and cognitive dysfunction associated with long COVID-19. Sphenopalatine ganglion blocks have shown promise in managing refractory headache symptoms in this population. Further well-designed, placebo-controlled randomized studies that employ validated outcome measures are required to establish the efficacy of sympathetic ganglion blocks in the treatment of long COVID-19.

INTRODUCTION:Phenylephrine infusion is widely endorsed by guidelines as the preferred prophylactic drug for spinal hypotension in patients undergoing caesarean delivery; however, clinical practice continues to show marked variability in the selection of vasopressor drugs. To address this, we aimed to synthesise current evidence from randomised controlled trials comparing vasopressor infusions for various feto-maternal outcomes in normotensive adult patients undergoing caesarean delivery. METHODS:Randomised controlled trials evaluating maternal and fetal outcomes associated with prophylactic vasopressor infusion were identified through comprehensive database searches. Primary outcomes were the incidence of maternal hypotension and umbilical artery base excess. Secondary outcomes comprised maternal and fetal parameters including: umbilical artery and vein pH; umbilical vein base excess; Apgar scores at 1 min and 5 min; and incidence of maternal intra-operative nausea and vomiting, bradycardia, tachycardia and hypertension. RESULTS:Fifty-five trials involving 5487 patients undergoing caesarean delivery under spinal or combined spinal and epidural anaesthesia using a variety of vasopressor infusions were included in the final analysis. Four drugs-metaraminol, noradrenaline, phenylephrine and adrenaline-were judged to be 'definitely superior' to control (no active vasopressor infusion) for the prevention of hypotension. Umbilical vessel analyses indicated that mephentermine and metaraminol provided superior preservation of both umbilical arterial and venous acid-base balance. DISCUSSION:Current evidence suggests that continuous infusions of α-agonists with mild β-activity (e.g. noradrenaline, metaraminol) are preferable to mixed adrenergic agonists such as ephedrine for preventing maternal hypotension. While these findings reinforce existing recommendations for maternal haemodynamic management, the evidence base for fetal outcomes remains limited.

Background and Aims: Ketamine is being proposed for the prevention of rebound pain. This meta-analysis systematically reviews evidence from randomised controlled trials on the efficacy of ketamine (intravenous or perineural) in preventing rebound pain in adults undergoing surgery under regional nerve block. Methods: A systematic search for randomised controlled trials evaluating ketamine/esketamine (perineural or intravenous) for preventing rebound pain was conducted across databases up to March 2025. Adults receiving regional nerve block with or without ketamine/esketamine were included. The primary outcome was the incidence of rebound pain. Secondary outcomes included onset time and severity of rebound pain, patient satisfaction, and adverse effects. Results: Six trials enroling 890 patients were included. Ketamine/esketamine significantly reduced the incidence of rebound pain [odds ratio (OR) 0.43, 95% confidence interval (CI) 0.32 to 0.59; P < 0.00001; I² = 39%]. The intravenous subgroup showed a significant reduction (OR 0.48, 95% CI 0.34 to 0.68; P < 0.00001; I² = 21%). The esketamine-versus-control subgroup also favoured active treatment (OR 0.37, 95% CI 0.22 to 0.64; P = 0.0004; I² = 51%). Hallucinations were significantly more frequent with active treatment (OR 12.73, 95% CI 2.98 to 54.41; P = 0.0006; I² = 0%). Conclusion: Current evidence suggests that intravenous and perineural ketamine/esketamine reduce the incidence of rebound pain after a peripheral regional nerve block.

Background and Aims: Various regional analgesia techniques, such as thoracic paravertebral (TPV) and serratus anterior plane (SAP) blocks, have been employed to manage postoperative pain following chest wall surgery. However, the comparative analgesic efficacy of these two approaches remains uncertain. This systematic review and meta-analysis aimed to assess the relative analgesic efficacy of these blocks in chest wall surgeries, including breast and thoracic procedures. The primary objective was the time to first rescue analgesia, and the secondary objective encompassed opioid consumption within 24 h, pain scores at different time intervals, opioid-related adverse effects and block-related complications. Methods: A systematic search for randomised controlled trials (RCTs) was conducted in PubMed, EMBASE and Scopus databases, covering studies from their inception to September 2023. We included active treatment arms from RCTs comparing these analgesic modalities. Statistical analysis was conducted in Review Manager Version 5.3, and results were analysed and reported separately for breast and thoracic surgery subgroups. Results: Eighteen trials enroling 1141 patients were included. Overall, no significant difference was observed in time to rescue analgesia, with a mean difference of 0.69 h (95% confidence interval −1.83, 0.45; P = 0.24, I2 = 98%) between the SAP and TPV block groups. However, the TPV block demonstrated superior results for secondary outcomes in thoracic surgery patients. Complications related to the TPV block included pleural puncture and haematoma at the injection site. Conclusions: The evidence suggests that both blocks generally offer comparable analgesic efficacy for chest wall surgery patients, with the TPV block providing a slight advantage for those undergoing thoracic surgery.

INTRODUCTION:Rebound pain, characterised by intense pain or discomfort as the effects of a peripheral nerve block diminish, remains a clinical problem. Peri-operative dexamethasone administration may reduce the incidence of rebound pain. This systematic and network meta-analysis aimed to determine the optimal route of dexamethasone administration for the prevention of rebound pain. METHODS:We searched databases for randomised controlled trials according to pre-determined criteria. We compared intravenous and perineural dexamethasone as an adjunct to peripheral nerve blocks, with the control group as a common comparator. The primary outcome was the incidence of rebound pain. The likelihood of an intervention ranking highest was calculated using the surface area under the cumulative ranking curve. RESULTS:In total, 14 studies with 1058 patients were included. When compared with the comparator group, we found that intravenous dexamethasone ranked the highest, with an anticipated effect of 298 fewer cases of rebound pain per 1000 people (odds ratio (OR) (95% credible interval (CrI) 0.12 (0.03-0.44)); moderate certainty evidence). This was followed by perineural dexamethasone with an anticipated effect of 190 fewer cases per 1000 people (OR (95%CrI) 0.34 (0.07-1.32); low certainty evidence). There was no evidence of an effect between the route of administration and time to onset of rebound pain. DISCUSSION:Intravenous dexamethasone was associated with a high probability of decreasing the incidence of rebound pain following peripheral nerve block. This is based on moderate certainty of evidence. Future studies on identifying the optimal dose are now warranted.

BACKGROUND:Epidural analgesia and dural puncture epidural (DPE) analgesia are widely used techniques for alleviating labour pain. This meta-analysis compared clinical outcomes between parturients receiving epidural analgesia vs DPE analgesia for labour pain. METHODS:Medical databases were searched to identify randomised controlled trials comparing epidural analgesia with DPE analgesia in labouring parturients published up to October 2024. Results were pooled using an inverse variance random-effects model, and 95% prediction intervals were calculated. Clinical outcomes were used as defined by individual trials. The primary outcome was time to onset of analgesia. Secondary outcomes were unilateral block, motor block, sacral sparing, adequate analgesia, Caesarean/operative vaginal delivery, additional doses, and hypotension. The certainty of evidence was assessed using Grading of Recommendations Assessment, Development, and Evaluation guidelines, and subgroup analyses were performed based on the types of local anaesthetics used. RESULTS:Eighteen trials involving 2144 parturients were included. DPE labour analgesia slightly reduced the time to onset (mean difference: 3.4 min, 95% confidence interval: 2.1-4.7, P<0.01, I2=97%; moderate certainty). All statistically significant results demonstrated clinical advantages for DPE analgesia, including fewer unilateral blocks, reduced motor block, improved sacral coverage, and higher rates of adequate analgesia. Substantial heterogeneity was observed in the outcome data for time to onset of analgesia, unilateral block, and sacral sparing. Pooled results for Caesarean/operative vaginal delivery, additional doses, and hypotension failed to achieve statistical significance. CONCLUSIONS:DPE labour analgesia offers a slightly faster onset and reduced incidence of motor and unilateral blocks compared with traditional epidural analgesia. However, high heterogeneity in some outcomes, likely attributable to clinical and dosing variability, requires cautious interpretation. Although the clinical relevance of the faster onset with DPE analgesia might be modest, when considered alongside its benefits in secondary outcomes it supports the use of DPE analgesia over traditional epidural analgesia. Imputed prediction intervals cross zero for many outcomes, and further studies might alter these findings. CLINICAL TRIAL REGISTRATION:PROSPERO- CRD42024602115.

By reading this article, you should be able to: •Describe the risk factors and predictors for spinal anaesthesia-mediated hypotension (SAMH) during Caesarean section. •Discuss recent advances in the detection of hypotension by non-invasive measures. •Review the risks and benefits of different pharmacological options to treat SAMH. Adithya Devadas Bhat MD is an obstetric anaesthesiologist at Northwestern University Feinberg School of Medicine with special interests in quality of care in obstetric anaesthesia, medical simulation and curriculum development. Preet Mohinder Singh MD is an obstetric anaesthesiologist at Washington University School of Medicine in St. Louis. His professional focus revolves around epidemiological and outcomes research within the realm of anaesthesiology. Arvind Palanisamy MD FRCA is the division chief of obstetric anesthesiology at Washington University School of Medicine in St. Louis. He is an active researcher covering the entire spectrum from basic sciences to clinical and epidemiological research in maternal and neonatal health.

Background Over the last two decades, significant research interest has led to the development of a wide variety of supraglottic airways (SGAs) for anaesthesia providers to choose from. Methods In this network meta-analysis, we analysed 111 studies, enrolling 12 045 patients undergoing airway management with 29 SGAs. We targeted outcomes that contribute to clinicians' choice of one SGA over another. The primary outcome was the incidence of postoperative sore throat (POST). Secondary outcomes were first-attempt insertion success, bleeding complications, and oropharyngeal leak pressure (OLP). Based on credible intervals, we created a ‘rank order’ to guide decision-making for clinicians. Results The highest-ranking devices based on credible intervals for POST, bleeding complications, first-attempt insertion success, and OLP were LMA Ambu, Jcerity Endoscoper, LMA Blockbuster, and LMA Baska Mask, respectively. Air-Q and i-gel ranked favourably across multiple outcomes, with i-gel being the only device to rank within the top six SGAs for POST, bleeding, and first-attempt success despite ranking poorly for OLP. Conclusions Our data support the use of LMA-Ambu, Jcerity-Endoscoper, Air-Q, and i-gel when considering patient-centred outcomes. Clinician familiarity with these devices and their continued expansion into anaesthetic practice will have important implications on the perioperative patient experience. Systematic review protocol PROSPERO (CRD42022383136).

Background and Aims: Postoperative neurocognitive dysfunction (PNCD) commonly occurs after surgery and prolongs hospital stays. Both direct noxious stimuli to the central nervous system and systemic inflammation have been implicated. Due to their potent anti-inflammatory effects, corticosteroids have been utilised to attenuate the incidence and severity of PNCD. This systematic review and meta-analysis strived to evaluate the prophylactic role of perioperative corticosteroids for PNCD. Methods: A search was run in pre-defined databases for randomised controlled trials (RCTs) assessing the role of corticosteroids in preventing PNCD. The incidence of PNCD within 1 month was the primary outcome. Secondary outcomes included the use of antipsychotic medications for the treatment, postoperative infection, and hospital length of stay. The results are exhibited as odds ratio (OR) and the mean difference (MD) with 95% confidence interval (CI). Results: Fifteen RCTs comprising 15,398 patients were included. The incidence of PNCD was significantly lower in the corticosteroid group than in the control group, with a pooled OR of 0.75 (95% CI 0.58, 0.96; P = 0.02; I2 = 66%). Trial sequential analysis showed the clinical benefit of corticosteroids in preventing PNCD; however, the requisite information size is still inadequate. The sub-group analysis supported the prophylactic effect of corticosteroids on delirium prevention but not on delayed neurocognitive recovery. Conclusions: Our meta-analysis revealed statistically significant protective effects of corticosteroids on the incidence of PNCD. However, further studies are still needed to confirm the protective role of this commonly used and relatively safe strategy for preventing PNCD.

( Anaesthesia . 2024, 79, 461–464. doi:10.1111/anae.16230) It is uncommon for maternal cardiac arrests (CA) to occur, leading to limited opportunities to learn from these unfortunate occurrences. The 7th National Audit Project (NAP7) organizers should be commended for adjusting their approach to incorporate instances of CA in obstetric patients receiving anesthesia, regardless of their location. The study conducted by Lucas and colleagues offers valuable findings on anesthetic care during childbirth to avoid rare yet severe occurrences. The results suggest that the primary reason for most maternal CAs in NAP7 was related to anesthetic management factors. This aligns with additional studies, like the CAPS research, that found comparable results regarding maternal CA from obstetric anesthesia.

Background/importancePostoperative neurocognitive dysfunction (PNCD) is a frequent and preventable complication after surgery. The large high-quality evidence for the efficacy of supplemental regional analgesia blocks (RAB) for preventing PNCD is still elusive. ObjectiveThe objective of this meta-analysis was to evaluate the effect of RAB versus standard anesthesia care on the incidence of PNCD in adult patients undergoing major non-cardiac surgery. Evidence reviewPubMed, EMBASE, Scopus, and the Cochrane Central Registers of Controlled Trials (CENTRAL) were searched for randomized controlled trials (RCTs) from 2017 until June 2022. The primary outcome was the incidence of PNCD within 1 month of surgery. A random-effects model with an inverse variance method was used to pool results, and OR and mean differences were calculated for dichotomous and continuous outcomes. Various exploratory subgroup analyses were performed to explore the possibility of the association between the various patient, technique, and surgery-related factors. Grading of Recommendation, Assessment, Development, and Evaluation guidelines were used to determine the certainty of evidence. FindingsTwenty-six RCTs comprizing 4414 patients were included. The RAB group was associated with a significant reduction in the incidence of PNCD with an OR of 0.46 (95% CI 0.35 to 0.59; p<0.00001; I-2=28%) compared with the control group (moderate certainty). Subgroup analysis exhibited that the prophylactic efficacy of RAB persisted for both delirium and delayed neurocognitive recovery. ConclusionsCurrent evidence suggests that supplemental RAB are beneficial in preventing PNCD in patients after major non-cardiac surgery. PROSPERO registration numberCRD42022338820

OBJECTIVES:Both superficial and deep serratus anterior plane (SAP) blocks are effective for anterior chest wall surgeries, but there is little clarity on which is more effective. Hence, we conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) to evaluate the comparative efficacy of the 2 approaches for SAP block after anterior chest wall surgery. MATERIALS AND METHODS:A systematic literature search was performed using PubMed, Embase, Scopus, and Cochrane Central Registers of Controlled Trials for eligible RCTs from inception until August 2023. The primary outcome was opioid consumption during the first 24 hours of the postoperative period. The secondary outcomes included pain scores at various intervals, intraoperative opioid consumption, time to first analgesic request, block-related complications, opioid-related side effects, and patient satisfaction scores. Statistical analysis of the pooled data was performed using Review Manager Version 5.3. RESULTS:We identified 7 RCTs published between 2020 and 2022, enrolling 371 patients (186 in the superficial SAP block and 187 in the deep SAP block). Moderate certainty of evidence suggests that both the approaches (deep and superficial) of SAP block were comparable for 24-hour oral morphine equivalent consumption with a mean difference (MD) of 3.78 mg (95% CI: -1.70 to 9.29; P = 0.18; I2 = 87%). The results of other secondary outcomes were comparable, including resting pain scores with an MD of 0.08 (95% CI: -0.27 to 0.43; P = 0.67; I2 = 87%) for early pain and MD of 0.63 (95% CI: -1.28 to 0.01; P = 0.05; I2 = 95%) for late pain scores, time to first analgesic request with MD of -0.41 hour (95% CI: -1.40 to 0.59; P = 0.42; I2 = 90%), and incidence of postoperative nausea and vomiting (odds ratio: 1.45 (95% CI: 0.72 to 2.90; P = 0.30; I2 = 0%). CONCLUSION:Current evidence does not support the preference for one approach of SAP block over the other for postoperative pain. Based on the available data, we recommend further future trials to determine any differences between these interventions.

( Anaesthesia . 2023;78(11):1347–1353. doi: 10.1111/anae.16109) Postpartum hemorrhage (PPH) is a leading cause of maternal mortality worldwide. The most common uterotonic agent used to prevent and treat PPH is oxytocin. In up to 38.8% of cases, oxytocin is unable to produce adequate uterine contractility and more uterotonic agents are required. Precise oxytocin dosing is ideal to balance PPH prevention/treatment and also avoid significant adverse side effects that can arise from high doses of oxytocin. While many factors contribute to the correct dosage for each individual, pharmacokinetic and pharmacodynamic data could assist in determining dosing for individual patients to both maximize desired effects and minimize adverse ones. This study was designed to obtain pharmacokinetic data to optimize the adjustment of oxytocin doses by patient weight, as well as to evaluate the relationship between serum oxytocin concentration and uterotonic and hemodynamic effects of the medication.

Objectives:Both superficial and deep serratus anterior plane (SAP) blocks are effective for anterior chest wall surgeries, but there is little clarity on which is more effective. Hence, we conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) to evaluate the comparative efficacy of the 2 approaches for SAP block after anterior chest wall surgery.Materials and Methods:A systematic literature search was performed using PubMed, Embase, Scopus, and Cochrane Central Registers of Controlled Trials for eligible RCTs from inception until August 2023. The primary outcome was opioid consumption during the first 24 hours of the postoperative period. The secondary outcomes included pain scores at various intervals, intraoperative opioid consumption, time to first analgesic request, block-related complications, opioid-related side effects, and patient satisfaction scores. Statistical analysis of the pooled data was performed using Review Manager Version 5.3.Results:We identified 7 RCTs published between 2020 and 2022, enrolling 371 patients (186 in the superficial SAP block and 187 in the deep SAP block). Moderate certainty of evidence suggests that both the approaches (deep and superficial) of SAP block were comparable for 24-hour oral morphine equivalent consumption with a mean difference (MD) of 3.78 mg (95% CI: -1.70 to 9.29; P = 0.18; I 2 = 87%). The results of other secondary outcomes were comparable, including resting pain scores with an MD of 0.08 (95% CI: -0.27 to 0.43; P = 0.67; I 2 = 87%) for early pain and MD of 0.63 (95% CI: -1.28 to 0.01; P = 0.05; I 2 = 95%) for late pain scores, time to first analgesic request with MD of -0.41 hour (95% CI: -1.40 to 0.59; P = 0.42; I 2 = 90%), and incidence of postoperative nausea and vomiting (odds ratio: 1.45 (95% CI: 0.72 to 2.90; P = 0.30; I 2 = 0%).Conclusion:Current evidence does not support the preference for one approach of SAP block over the other for postoperative pain. Based on the available data, we recommend further future trials to determine any differences between these interventions.

We appreciate the authors' interest in our systematic review and meta-analysis examining the effect of corticosteroids on postoperative neurocognitive disorders (PNCDs).[1,2] In our methodology, PNCD was defined as per the original author and encompassed trials assessing PNCD within one month. It is important to note that studies by Dieleman et al.,[3] Ottens et al.[4] and Sauër et al.[5] employed varying definitions and assessment periods for PNCD, leading to different outcomes. Specifically, Dieleman et al.[3] defined the occurrence of delirium as the use of neuroleptic drugs rather than the use of an assessment tool over 30 days, suggesting delirium might be under-recognised. Ottens et al.[4] determined cognitive outcomes by administering a battery of five neuropsychological tests at one month. Sauër et al.[5] defined PNCD as delirium, and the patient was evaluated using the Confusion Assessment Method 4 days postoperatively. The authors stated, 'in that study, the presence of delirium was defined by the postoperative use of an antipsychotic medication(s), rather than based on delirium screening using a validated instrument, and thus it is likely that delirium was under-recognised'[3] and used this as an objective for formulating their trial. Consequently, despite some overlap in sample size, each study might have reported a different or added patient population, leading to additional information. In the absence of further clarifications of these issues, we treated these studies as independent samples, as they addressed different clinical outcomes in our analysis. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.

BACKGROUND:Fasting before elective anesthesia care is a standardized practice worldwide. The aim is to decrease the risk of aspiration leading to pulmonary complications such as aspiration pneumonitis during anesthesia care. There are different guidelines for elective preoperative fasting in children. However, there is insufficient literature measuring gastric emptying time after breast milk or formula milk feeding in infants.OBJECTIVE:This study used gastric ultrasound to determine the gastric emptying time for breast milk and formula milk in children below 6 months of age. We also compared the calculated gastric volumes among breast-fed and formula milk-fed based on Schmitz's and Spencer's formula.MATERIALS AND METHODS:This prospective observational study was conducted at a tertiary care center in India between November (2017-2019). A total of 52 infants less than 6 months of age were recruited. The study population was divided into two groups (breast-fed and formula milk-fed) of 26 patients each. Ultrasound was used to measure the antral cross-sectional area of the stomach and to calculate the gastric volume using the two classical formulas (Schmitz and Spencer's). Gastric emptying was reported when the bull's eye appearance of the gastric antrum was seen or when the antral cross-sectional area was less than 3.07 cm2.RESULTS:The number of breast-fed children whose antral cross-sectional was greater than 3.07 cm2 (cut-off value for aspiration risk) beyond 1 h was 14/26 (53.84%) while none (0) children went beyond 3 h. The number of formula-fed children whose antral cross-sectional was greater than 3.07 cm2 beyond 1 h was 17/26 (65.38%) while one child (3.84%) went beyond 3 h. Using Schmitz's formula, mean (SD) gastric emptying times were 0.35 ± 0.68 h (95% CI 0.35 ± 0.185, range 0.165-0.535) for breast-fed patients and 0.35 ± 0.69 h (95% CI 0.35 ± 0.188, range 0.162-0.538) for formula-fed patients, and were thus neither clinically nor statistically different (p = .73) Using Spencer's formula, the mean gastric emptying times were 0.12 ± 0.33 h (95% CI 0.12 ± 0.09, range 0.03-0.21) for breast-fed patients and 0.04 ± 0.20 h (95% CI 0.04 ± 0.05, range -0.01 to 0.09) for formula-fed patients, and were also neither clinically nor statistically different p = .13.CONCLUSION:In our series, the gastric emptying times in breast-fed and formula-fed infants less than 6 months old were similar. Our results support the fasting guidelines of the European Society of Anaesthesiology and Intensive Care 2022, that is, 3 h for breastfeeding and 4 h for formula milk feeding. In addition, this shows that the Schmitz's and Spencer's formulae used to calculate the gastric volume based on ultrasound measurement of the antral cross-sectional area are not comparable in infants less than 6 months.

Introduction Shivering affects 52 % of patients undergoing caesarean delivery under neuraxial anaesthesia. Despite extensive research focused on its prevention, there is still no consensus regarding optimal pharmacological treatment. This systematic review and network meta-analysis aims to compare available intravenous treatments of perioperative shivering in patients undergoing caesarean delivery under neuraxial anaesthesia. Methods We searched seven databases (PubMed MEDLINE, Scopus, Web of Science, Embase, LILACS, Cochrane CRCT and clinicaltrials.gov) for randomised controlled trials comparing intravenous treatments of perioperative shivering during caesarean delivery and performed a Bayesian model network meta-analysis. We assessed study quality using the Cochrane risk of bias assessment tool. The primary outcome evaluated in this meta-analysis was shivering control (cessation or significant reduction in intensity), and secondary outcomes included time to shivering control, shivering recurrence, and incidence of maternal nausea. Results Twenty randomised controlled trials, with a total of 1983 patients, were included in this analysis. Network estimates of odds ratios (OR [95 % Credible Interval]) of effective treatment of shivering compared with saline were: dexmedetomidine (38.1 [14.2 to 111.5]), tramadol (33.6 [15.1 to 81.8]), nalbuphine (26.2 [10.8 to 80.2]), meperidine (20.9 [6.2 to 73.1]), ondansetron (6.6 [2.2 to 23.2]), and clonidine (3.2 [0.6 to 14.9]). The rank order of interventions by surface area under the cumulative ranking curve scores (in parenthesis) for shivering control was dexmedetomidine (0.87) > tramadol (0.85) > nalbuphine (0.74) > meperidine (0.66) > ondansetron (0.41) > clonidine (0.3) > amitriptyline (0.03). Dexmedetomidine was also the top-ranked intervention for time to shivering control, shivering recurrence and maternal nausea. We judged the certainty in the evidence to be moderate for dexmedetomidine and nalbuphine, and low for all other interventions. Conclusion This network meta-analysis identified four effective intravenous treatments for shivering in patients undergoing caesarean delivery under neuraxial anaesthesia: dexmedetomidine, tramadol, nalbuphine and meperidine. Dexmedetomidine was the top-ranked intervention for all outcomes.