Influence of different volumes and frequency of programmed intermittent epidural bolus in labor on maternal and neonatal outcomes: A systematic review and network meta-analysis.

STUDY OBJECTIVE: In labor, programmed intermittent epidural bolus (PIEB) can be defined as the bolus administration of epidural solution at scheduled time intervals. Compared to continuous epidural infusion (CEI) with or without patient controlled epidural analgesia (PCEA), PIEB has been associated with decreased pain scores and need for rescue analgesia and increased maternal satisfaction. The optimal volume and dosing interval of PIEB, however, has still not been determined. DESIGN: Systematic review and network meta-analysis registered with PROSPERO (CRD42022362708). SETTINGS: Labor. PATIENTS: Pregnant patients. INTERVENTIONS: Central, CINAHL, Global Health, Ovid Embase, Ovid Medline and Web of Science were searched for randomized controlled trials that examined pregnant patients in labor who received CEI or PIEB with or without a PCEA component. Network meta-analysis was performed with a frequentist method, facilitating the indirect comparison of PIEB with different volumes and dosing intervals through the common comparator of CEI and substituting or supplementing direct comparisons with these indirect ones. Continuous and dichotomous outcomes were presented as mean differences and odds ratios, respectively, with 95% confidence intervals. The risk of bias was evaluated using the Cochrane risk of bias 2 tool. MAIN RESULTS: Overall, 30 trials were included. For the first primary endpoint, need for rescue analgesia, PIEB delivered at a volume of 4 ml and frequency of 45 min (4/45) was inferior to PIEB 8/45 (OR 3.55; 95% CI 1.12-11.33), PIEB 10/60 was superior to PIEB 2.5/15 (OR 0.36; 95% CI 0.16-0.82), PIEB 4/45 (OR 0.14; 95% CI 0.03-0.71) and PIEB 5/60 (OR 0.23; 95% CI 0.08-0.70), and PIEB 5/30 was not inferior to PIEB 10/60 (OR 0.61; 95% CI 0.31-1.19). For the second primary endpoint, maternal satisfaction, no differences were present between the various PIEB regimens. The quality of evidence for these multiple primary endpoints was low owing to the presence of serious limitations and imprecision. Importantly, PIEB 5/30 decreased the pain score at 4 h compared to PIEB 2.5/15 (MD 2.45; 95% CI 0.13-4.76), PIEB 5/60 (MD -2.28; 95% CI -4.18--0.38) and PIEB 10/60 (MD 1.73; 95% CI 0.31-3.16). Mean ranking of interventions demonstrated PIEB 10/60 followed by PIEB 5/30 to be best placed to reduce the cumulative dose of local anesthetic, and this resulted in an improved incidence of lower limb motor blockade for PIEB 10/60 in comparison to CEI (OR 0.30; 95% CI 0.14-0.67). No differences in neonatal outcomes were found. Some concerns were present for the risk of bias in two thirds of trials and the risk of bias was shown to be high in the remaining one third of trials. CONCLUSIONS: Future research should focus on PIEB 5/30 and PIEB 10/60 and how the method of analgesia initiation, nature and concentration of local anesthetic, design of epidural catheter and rate of administration might influence outcomes related to the mother and neonate.

Evaluation of the 'Sip Til Send' regimen before elective caesarean delivery using bedside gastric ultrasound: A paired cohort pragmatic study.

BACKGROUND: Pre-operative fasting is routinely advocated to avoid pulmonary aspiration. The European Society of Anaesthesiology and Intensive Care (ESAIC) recommends a fasting period of 2 h for liquids before surgery. Liberal drinking policies such as the 'Sip Til Send' are a suggested alternative to maintain hydration before surgery. OBJECTIVES: To compare residual gastric volumes in fully fasted nonlabouring parturients before elective caesarean delivery with the 'Sip Til Send' with water liberal drinking protocol. Our hypothesis was the 'Sip Til Send' would be noninferior to standard fasting at minimising the residual gastric volume immediately before surgery. DESIGN: A paired cohort prospective observational pragmatic study using gastric ultrasound, analysed by an operator blinded to the fasting status of each scan. SETTING: A tertiary maternity hospital in Dublin, Ireland. The study was conducted between January and June 2023. PARTICIPANTS: Pregnant women about to undergo elective caesarean delivery who had followed ESAIC fasting guidelines before admission. INTERVENTIONS: Each participant underwent two pairs (semi-recumbent and the semi-recumbent right lateral positions) of standardised ultrasound examinations of the gastric antrum: the order of these scans was randomised. The first pair of scans occurred on admission before the 'Sip Til Send' protocol commenced, the other pair just before spinal anaesthesia for caesarean delivery, after a variable time following the 'Sip Til Send' protocol. MAIN OUTCOME MEASURE: The primary outcome was the difference in antral cross-sectional area (CSA) between the fully fasted women on admission and the same women after following the 'Sip Til Send' protocol until just before spinal anaesthesia. RESULTS: Fifty-eight women were randomised for the study: 55 and 54 scans in the semi-recumbent position on admission, and 55 and 54 scans in the right lateral position just before spinal anaesthesia. The mean differences (95% CI) in CSA in the semi-recumbent and RL positions were 0.07 (-0.39 to 0.53) cm 2 and 0.04 (-0.60 to 0.68) cm 2 , respectively. Since the of 95% CIs did not cross the predefined noninferiority margin of 0.88 cm 2 , 'Sip Til Send' was noninferior to fully fasting in in terms of the antral CSA. CONCLUSION: The 'Sip Til Send' protocol of liberal hydration with water was noninferior to standard fasting prior to elective caesarean delivery. TRIAL REGISTRY NUMBER: NCT05783427 ClinicalTrials.gov.

Investigating the Influence of Anaesthesiology for Cancer Resection Surgery on Oncologic Outcomes: The Role of Experimental In Vivo Models.

The incidence and societal burden of cancer is increasing globally. Surgery is indicated in the majority of solid tumours, and recent research in the emerging field of onco-anaesthesiology suggests that anaesthetic-analgesic interventions in the perioperative period could potentially influence long-term oncologic outcomes. While prospective, randomised controlled clinical trials are the only research method that can conclusively prove a causal relationship between anaesthetic technique and cancer recurrence, live animal (in vivo) experimental models may more realistically test the biological plausibility of these hypotheses and the mechanisms underpinning them, than limited in vitro modelling. This review outlines the advantages and limitations of available animal models of cancer and how they might be used in perioperative cancer metastasis modelling, including spontaneous or induced tumours, allograft, xenograft, and transgenic tumour models.

Comparison of analgesic modalities for patients undergoing midline laparotomy: a systematic review and network meta-analysis.

BACKGROUND: Midline laparotomy is associated with severe pain. Epidural analgesia has been the established standard, but multiple alternative regional anesthesia modalities are now available. We aimed to compare continuous and single-shot regional anesthesia techniques in this systematic review and network meta-analysis. METHODS: We included randomized controlled trials on adults who were scheduled for laparotomy with solely a midline incision under general anesthesia and received neuraxial or regional anesthesia for pain. Network meta-analysis was performed with a frequentist method, and continuous and dichotomous outcomes were presented as mean differences and odds ratios, respectively, with 95% confidence intervals. The quality of evidence was rated with the  grading of recommendations, assessment, development, and evaluation system. RESULTS: Overall, 36 trials with 2,056 patients were included. None of the trials assessed erector spinae plane or quadratus lumborum block, and rectus sheath blocks and transversus abdominis plane blocks were combined into abdominal wall blocks (AWB). For the co-primary outcome of pain score at rest at 24 hr, with a minimal clinically important difference (MCID) of 1, epidural was clinically superior to control and single-shot AWB; epidural was statistically but not clinically superior to continuous wound infiltration (WI); and no statistical or clinical difference was found between control and single-shot AWB. For the co-primary outcome of cumulative morphine consumption at 24 hr, with a MCID of 10 mg, epidural and continuous AWB were clinically superior to control; epidural was clinically superior to continuous WI, single-shot AWB, single-shot WI, and spinal; and continuous AWB was clinically superior to single-shot AWB. The quality of evidence was low in view of serious limitations and imprecision. Other results of importance included: single-shot AWB did not provide clinically relevant analgesic benefit beyond two hr; continuous WI was clinically superior to single-shot WI by 8-12 hr; and clinical equivalence was found between epidural, continuous AWB, and continuous WI for the pain score at rest, and epidural and continuous WI for the cumulative morphine consumption at 48 hr. CONCLUSIONS: Single-shot AWB were only clinically effective for analgesia in the early postoperative period. Continuous regional anesthesia modalities increased the duration of analgesia relative to their single-shot counterparts. Epidural analgesia remained clinically superior to alternative continuous regional anesthesia techniques for the first 24 hr, but reached equivalence, at least with respect to static pain, with continuous AWB and WI by 48 hr. TRIAL REGISTRATION: PROSPERO (CRD42021238916); registered 25 February 2021.

RéSUMé: CONTEXTE: La laparotomie médiane est associée à une douleur sévère. L'analgésie péridurale est la norme de soins établie, mais plusieurs modalités alternatives d'anesthésie régionale sont aujourd'hui disponibles. Dans cette revue systématique et méta-analyse en réseau, nous avons cherché à comparer les techniques d'anesthésie régionale continue et par injection unique. MéTHODE: Nous avons inclus les études randomisées contrôlées portant sur des adultes devant bénéficier d'une laparotomie avec une simple incision médiane sous anesthésie générale et qui ont reçu une anesthésie neuraxiale ou régionale pour la douleur. Une méta-analyse en réseau a été réalisée avec une méthode fréquentiste, et les résultats continus et dichotomiques ont été présentés sous forme de différences moyennes et de rapports de cotes, respectivement, avec des intervalles de confiance à 95 %. La qualité des données probantes a été évaluée avec le système GRADE (Grading of Recommendations Assessment, Development and Evaluation). RéSULTATS: Au total, 36 études portant sur 2056 patients ont été incluses. Aucune des études n'a évalué le bloc du plan des muscles érecteurs du rachis ou du carré des lombes. Les blocs de la gaine des grands droits et du plan des muscles transverses de l'abdomen ont été combinés en blocs de la paroi abdominale (BPA). Concernant le critère d'évaluation principal de score de douleur au repos à 24 heures, avec une différence minimale cliniquement pertinente (DMCP) de 1, l'analgésie péridurale était cliniquement supérieure au BPA de contrôle et par injection unique; l'analgésie péridurale était statistiquement mais non cliniquement supérieure à l'infiltration continue de la plaie; et aucune différence statistique ou clinique n'a été constatée entre le BPA de contrôle et par injection unique. Pour le deuxième critère d'évaluation principal portant sur la consommation cumulative de morphine à 24 heures, avec une DMCP de 10 mg, la péridurale et le BPA continu étaient cliniquement supérieurs au groupe contrôle; la péridurale était cliniquement supérieure à l'infusion continue de la plaie, au BPA par injection unique, à l'infiltration par injection unique de la plaie et à la rachianesthésie; et le BPA continu était cliniquement supérieur au BPA par injection unique. La qualité des données probantes était faible compte tenu d'importantes limites et d'imprécisions. De plus, le BPA par injection unique n'a fourni aucun avantage analgésique cliniquement pertinent au-delà de deux heures; l'infiltration continue de la plaie était cliniquement supérieure de 8 à 12 heures à l'infiltration de la plaie en injection unique; et une équivalence clinique a été observée entre la péridurale, le BPA continu et l'infiltration continue de la plaie en ce qui avait trait au score de douleur au repos, et entre la péridurale et l'infiltration continue de la plaie en ce qui touchait à la consommation cumulative de morphine à 48 heures. CONCLUSION: Les BPA par injection unique n'étaient cliniquement efficaces pour procurer une analgésie qu'au début de la période postopératoire. Les modalités d'anesthésie régionale continue ont augmenté la durée de l'analgésie par rapport aux modalités équivalentes par injection unique. L'analgésie péridurale est demeurée cliniquement supérieure aux techniques alternatives d'anesthésie régionale continue pendant les 24 premières heures, mais a atteint l'équivalence, au moins en ce qui concerne la douleur statique, avec les BPA et les infiltrations de lésions continus à 48 heures. Enregistrement de l'étude : PROSPERO (CRD42021238916); enregistrée le 25 février 2021.

Infiltration between the popliteal artery and the capsule of the knee (IPACK) block in knee surgery: a narrative review.

BACKGROUND: The infiltration between the popliteal artery and the capsule of the knee (IPACK) block has been described as an alternative analgesic strategy for knee pain. OBJECTIVE: Our aim was to perform a narrative review to examine the place and value that the IPACK block has in comparison to and in conjunction with other regional anesthesia modalities. EVIDENCE REVIEW: Following an extensive search of electronic databases, we included anatomical studies, letters, comparative observational studies, and non-randomized and randomized controlled trials that examined the IPACK block in relation to surgery on the knee under general or neuraxial anesthesia. FINDINGS: In all, 35 articles were included. Cadaveric studies demonstrated the potential for injected dye to spread to the nerves responsible for the innervation of the posterior as well as anteromedial and anterolateral aspects of the knee. Of the comparative observational studies (n=15) and non-randomized (n=1) and randomized controlled trials (n=13), 2 and 27 were conducted in the context of anterior cruciate ligament reconstruction and knee replacement surgery, respectively. The role of the IPACK block with each different permutation of regional anesthesia techniques was investigated by a small number of studies. Clinical studies, in the setting of knee replacement surgery, revealed variation in the manner in which the IPACK block was performed, and indicated the possible superiority of distal injection at the level of the femoral condyles for the management of posterior knee pain. Evidence suggested the following: the IPACK block in combination with single shot adductor canal block (ACB) may be beneficial for analgesic and functional outcomes; in conjunction with single shot or continuous ACB, the IPACK block might be superior to local infiltration analgesia (LIA); and functional outcomes may be improved with the supplementation of continuous ACB and LIA with the IPACK block. The IPACK block did not commonly result in the occurrence of foot drop. Relative to tibial nerve block (TNB), the IPACK block reduced the occurrence of foot drop and increased the proportion of patients who were able to be discharged on the third postoperative day. CONCLUSIONS: The IPACK block was potentially complementary to the ACB and might be preferable to the TNB as a motor-sparing regional anesthesia technique in knee surgery. Definitive recommendations were not reached in the presence of the heterogeneous and limited evidence base.

Comparison of videolaryngoscopy and direct laryngoscopy for tracheal intubation in obstetrics: a mixed-methods systematic review and meta-analysis.

PURPOSE: The incidence of difficult and failed intubation is higher in obstetrical patients than in the general population because of anatomic and physiologic changes in pregnancy. Videolaryngoscopy improves the success rate of intubation and reduces complications when compared with direct laryngoscopy in adults; however, it is not known whether this extends to obstetrical surgery. The aim of this study was to examine the efficacy, efficiency, and safety of videolaryngoscopy compared with direct laryngoscopy in obstetrics. SOURCE: Central, CINAHL, Embase, MEDLINE and Web of Science databases were searched from inception to 27 May 2020 with no restrictions. Inclusion criteria included randomized-controlled trials (RCTs), observational studies, case series, and case reports that reported the application of videolaryngoscopy to intubate the trachea in pregnant patients having general anesthesia. PRINCIPAL FINDINGS: Overall, four RCTs with 428 participants, nine observational studies, and 35 case reports/series with 100 participants were included. On meta-analysis of three trials, the co-primary outcomes of first-attempt success rate (risk ratio, 1.02; 95% confidence intervals [CI], 0.98 to 1.06; P = 0.29; I2 = 0%) and time to tracheal intubation (mean difference, 1.20 sec; 95% CI, -6.63 to 9.04; P = 0.76; I2 = 95%) demonstrated no difference between videolaryngoscopy and direct laryngoscopy in parturients without difficult airways. Observational studies and case reports underline the role of videolaryngoscopy as a primary choice when difficulty with tracheal intubation is expected or as a rescue modality in difficult or failed intubations. CONCLUSIONS: Evidence for the utility of videolaryngoscopy continues to evolve but supports its increased adoption in obstetrics where videolaryngoscopes should be immediately available for use as a first-line device. TRIAL REGISTRATION: PROSPERO (CRD42020189521); registered 6 July 2020.

RéSUMé: OBJECTIF: L'incidence des intubations difficiles et de leur échec est plus élevée chez les patientes obstétricales que dans la population générale en raison des changements anatomiques et physiologiques liés à la grossesse. Chez l'adulte, la vidéolaryngoscopie améliore le taux de réussite de l'intubation et réduit les complications par rapport à la laryngoscopie directe; cependant, nous ne savons pas si ces avantages s'étendent également à la population obstétricale. L'objectif de cette étude était d'examiner l'efficacité, l'efficience et la sécurité de la vidéolaryngoscopie par rapport à la laryngoscopie directe en obstétrique. SOURCE: Les bases de données Central, CINAHL, Embase, MEDLINE et Web of Science ont été recherchées de leur création jusqu'au 27 mai 2020 sans restriction. Les critères d'inclusion comprenaient les études randomisées contrôlées (ERC), les études observationnelles, les séries de cas et les présentations de cas rapportant l'application de la vidéolaryngoscopie pour intuber la trachée de patientes enceintes recevant une anesthésie générale. CONSTATATIONS PRINCIPALES: Quatre ERC comptant 428 participantes, neuf études observationnelles et 35 présentations/séries de cas comptant 100 participantes ont été incluses. En effectuant une méta-analyse de trois études, les critères d'évaluation co-primaires du taux de réussite de l'intubation à la première tentative (risque relatif, 1,02; intervalle de confiance [IC] 95 %, 0,98 à 1,06; P = 0,29; I2 = 0 %) et le temps jusqu'à l'intubation endotrachéale (différence moyenne, 1,20 sec; IC 95 %, -6,63 à 9,04; P = 0,76; I2 = 95 %) n'ont démontré aucune différence entre la vidéolaryngoscopie et la laryngoscopie directe chez les parturientes ne présentant pas de difficultés au niveau des voies aériennes. Les études observationnelles et les présentations de cas soulignent le rôle de la vidéolaryngoscopie comme premier choix lorsque des difficultés sont anticipées pour l'intubation endotrachéale ou comme modalité de sauvetage dans les cas d'intubations difficiles ou ratées. CONCLUSION: Les données probantes concernant l'utilité de la vidéolaryngoscopie continuent d'évoluer mais appuient son adoption accrue en obstétrique, où des vidéolaryngoscopes devraient être immédiatement disponibles pour être utilisés comme dispositif de première ligne. ENREGISTREMENT DE L'éTUDE: PROSPERO (CRD42020189521); enregistrée le 6 juillet 2020.