Oxygenation during the apnoeic phase preceding intubation in adults in prehospital, emergency department, intensive care and operating theatre environments.

BACKGROUND: Apnoeic oxygenation is the delivery of oxygen during the apnoeic phase preceding intubation. It is used to prevent respiratory complications of endotracheal intubation that have the potential to lead to significant adverse events including dysrhythmia, haemodynamic decompensation, hypoxic brain injury and death. Oxygen delivered by nasal cannulae during the apnoeic phase of intubation (apnoeic oxygenation) may serve as a non-invasive adjunct to endotracheal intubation to decrease the incidence of hypoxaemia, morbidity and mortality. OBJECTIVES: To evaluate the benefits and harms of apnoeic oxygenation before intubation in adults in the prehospital, emergency department, intensive care unit and operating theatre environments compared to no apnoeic oxygenation during intubation. SEARCH METHODS: We used standard, extensive Cochrane search methods. The latest search date was 4 November 2022. SELECTION CRITERIA: We included randomized controlled trials (RCTs) and quasi-RCTs that compared the use of any form of apnoeic oxygenation including high flow and low flow nasal cannulae versus no apnoeic oxygenation during intubation. We defined quasi-randomization as participant allocation to each arm by means that were not truly random, such as alternation, case record number or date of birth. We excluded comparative prospective cohort and comparative retrospective cohort studies, physiological modelling studies and case reports. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. Our primary outcomes were 1. hospital stay and 2. incidence of severe hypoxaemia. Our secondary outcomes were 3. incidence of hypoxaemia, 4. lowest recorded saturation of pulse oximetry (SpO2), 5. intensive care unit (ICU) stay, 6. first pass success rate, 7. adverse events and 8. MORTALITY: We used GRADE to assess certainty of evidence. MAIN RESULTS: We included 23 RCTs (2264 participants) in our analyses. Eight studies (729 participants) investigated the use of low-flow (15 L/minute or less), and 15 studies (1535 participants) investigated the use of high-flow (greater than 15 L/minute) oxygen. Settings were varied and included the emergency department (2 studies, 327 participants), ICU (7 studies, 913 participants) and operating theatre (14 studies, 1024 participants). We considered two studies to be at low risk of bias across all domains. None of the studies reported on hospital length of stay. In predominately critically ill people, there may be little to no difference in the incidence of severe hypoxaemia (SpO2 less than 80%) when using apnoeic oxygenation at any flow rate from the start of apnoea until successful intubation (risk ratio (RR) 0.86, 95% confidence interval (CI) 0.66 to 1.11; P = 0.25, I² = 0%; 15 studies, 1802 participants; low-certainty evidence). There was insufficient evidence of any effect on the incidence of hypoxaemia (SpO2 less than 93%) (RR 0.58, 95% CI 0.23 to 1.46; P = 0.25, I² = 36%; 3 studies, 489 participants; low-certainty evidence). There may be an improvement in the lowest recorded oxygen saturation, with a mean increase of 1.9% (95% CI 0.75% to 3.05%; P < 0.001, I² = 86%; 15 studies, 1525 participants; low-certainty evidence). There may be a reduction in the duration of ICU stay with the use of apnoeic oxygenation during intubation (mean difference (MD) ‒1.13 days, 95% CI ‒1.51 to ‒0.74; P < 0.0001, I² = 46%; 5 studies, 815 participants; low-certainty evidence). There may be little to no difference in first pass success rate (RR 1.00, 95% CI 0.93 to 1.08; P = 0.79, I² = 0%; 8 studies, 826 participants; moderate-certainty evidence). There may be little to no difference in incidence of adverse events including oral trauma, arrhythmia, aspiration, hypotension, pneumonia and cardiac arrest when apnoeic oxygenation is used. There was insufficient evidence about any effect on mortality (RR 0.84, 95% CI 0.70 to 1.00; P = 0.06, I² = 0%; 6 studies, 1015 participants; low-certainty evidence). AUTHORS' CONCLUSIONS: There was some evidence that oxygenation during the apnoeic phase of intubation may improve the lowest recorded oxygen saturation. However, the differences in oxygen saturation were unlikely to be clinically significant. This did not translate into any measurable effect on the incidence of hypoxaemia or severe hypoxaemia in a group of predominately critically ill people. We were unable to assess the influence on hospital length of stay; however, there was a reduction in ICU stay in the apnoeic oxygenation group. The mechanism for this is unclear as there was little to no difference in first pass success or adverse event rates.

Comparison of Supraglottic Airway Devices With Endotracheal Intubation in Low-Risk Patients for Cesarean Delivery: Systematic Review and Meta-analysis.

BACKGROUND: The safety and adverse event rate of supraglottic airway (SGA) devices for cesarean delivery (CD) is poorly characterized. The primary aims of this review were to determine whether the first-pass success was higher and time to insertion for SGA was faster than endotracheal intubation for elective CD. The secondary aim was to determine the airway-related adverse event rate associated with SGA use compared to endotracheal intubation in elective CD under general anesthesia (GA). METHODS: Six databases were systematically searched until September 2019. Included studies reported on the use of SGA in comparison to endotracheal tube intubation. A comparative meta-analysis between SGA and endotracheal intubation was performed using RevMan 5.3 software. Dichotomous outcomes were reported using an odds ratio (OR) with 95% confidence interval (CI). The results for continuous outcomes were reported using a weighted mean difference (WMD) with 95% CI. RESULTS: Fourteen studies with 2236 patients compared SGA and endotracheal intubation. Overall, there was no statistically significant difference in first-attempt success rate (OR = 1.92; 95% CI, 0.85-4.32; I = 0%; P = .44). There was no clinically significant difference in time to insertion (WMD = -15.80 seconds; 95% CI, -25.30 to -6.31 seconds; I= 100%; P = .001). Similarly, there was no difference in any adverse event rate except sore throat which was reduced with the use of an SGA (OR = 0.16; 95% CI, 0.08-0.32; I= 53%; P < .001). CONCLUSIONS: Despite the reasonable insertion success rate and safety profile of SGAs demonstrated in this meta-analysis, the analysis remains underpowered and therefore inconclusive. At present, further studies are required before the use of an SGA as the first-line airway for an elective CD can be recommended.

Cricoid pressure during intubation: A systematic review and meta-analysis of randomised controlled trials.

PURPOSE: This systematic review and meta-analysis aimed to determine whether cricoid pressure protects against aspiration and whether this technique adversely affects intubating conditions in adult patients. METHODS: A systematic review of five databases was performed for randomised controlled trials comparing cricoid pressure to no cricoid or sham cricoid during intubation. The primary outcome was incidence of aspiration and the secondary outcomes included first attempt intubation success, time to intubation, Cormack and Lehane Grade 3 or 4 and difficult intubation. RESULTS: The search identified twelve high quality RCTs with 4,862 patients for inclusion. Among four studies reporting the primary outcome, there was no difference (RR=1.18; 95%CI=0.71 to 1.96; I2=0%; p=0.51). Only 3 studies were in patients at high risk of aspiration. There was significantly worse first attempt success (RR= 0.94; 95%CI= 0.89 to 0.99; I2=66%; p=0.02), time to intubation (WMD= 6.77seconds; 95%CI=4.40 to 9.14seconds; I2=97%) and laryngoscopy views (RR=1.69; 95%CI=1.41 to 2.02;I2=1%; p<0.00001) with cricoid pressure. CONCLUSIONS: Cricoid pressure failed to show any increase in protection from aspiration and may increase difficulty of intubation. Further studies in high-risk patients, such as intensive care patients, are required.

Apneic Oxygenation for Pediatric Endotracheal Intubation: A Narrative Review.

Apneic oxygenation (ApOx) has shown to be effective in adult populations in a variety of settings, including prehospital, emergency departments, intensive care units, and elective surgery. This review aims to assess the available literature for ApOx in the pediatric population to determine its effects on hypoxemia, safe apnea times, and flow rates employed safely.

Tramadol as an adjunct to intra-articular local anaesthetic infiltration in knee arthroscopy: a systematic review and meta-analysis.

BACKGROUND: Arthroscopic knee surgery is a common technique used in Australia. Post-operative pain is common and can lead to delayed discharge and impair early mobilization. Use of local anaesthesia can reduce pain while avoiding systemic side effects. This systematic review and meta-analysis aimed to establish the use of tramadol as an adjunct to intra-articular local anaesthetic infiltration in knee arthroscopy in the current literature. METHODS: Two independent reviewers performed a systematic search of four databases, where 24 articles were identified with six studies (four high-quality and two low-quality randomized controlled trials), with a total of 334 patients were included for analysis. RevMan 5.3 software (The Nordic Cochrane Centre, Copenhagen, Denmark) was used to perform the data analysis. The studies included focused on outcomes such as pain scores, breakthrough analgesia, total analgesia, time to discharge and adverse events related to the use of tramadol as an adjunctive therapy. RESULTS: This study found that using tramadol as an adjunct to intra-articular local anaesthetic infiltration in arthroscopic knee surgery reduced post-operative pain and increased time to breakthrough analgesia without an increase in side effects. CONCLUSION: This meta-analysis suggests that tramadol is an efficacious adjunct for use in intra-articular local anaesthetic infiltration following arthroscopic knee surgery.

Standard dose epinephrine versus placebo in out of hospital cardiac arrest: A systematic review and meta-analysis.

INTRODUCTION: Out of hospital cardiac arrest (OHCA) is a time critical and heterogeneous presentation. The most appropriate management strategies remain an issue for debate. The aim of this systematic review and meta-analysis was to determine the association of epinephrine versus placebo with return of spontaneous circulation, survival to hospital admission, survival to hospital discharge and neurological outcomes in out of hospital cardiac arrest. METHODS: A systematic review of five databases was performed from inception to August 2018. Only randomised controlled trials were considered eligible for inclusion. The primary outcome was survival to hospital discharge. Secondary outcomes were ROSC, survival to hospital admission, neurological function on discharge and three-month survival. All studies were assessed for level of evidence and risk of bias. RESULTS: Five randomised controlled trials with 17,635 patients were identified for inclusion. Use of epinephrine was associated with increased ROSC (OR = 3.10; 95% CI = 2.16 to 4.45; I2 = 74%; p < 0.0001) and increased survival to hospital admission OR = 2.52; 95% CI = 1.63 to 3.88; I2 = 94%; p < 0.0001). However, epinephrine was not associated with increased survival to discharge (OR = 1.09; 95% CI = 0.48 to 2.47; I2 = 77%; p = 0.84) or differences in neurological outcomes (OR = 0.81; 95% CI = 0.34 to 1.96). DISCUSSION: This study was a systematic review and meta-analysis of epinephrine versus placebo in OHCA. The use of epinephrine was associated with improved ROSC and survival to hospital admission. However, use of epinephrine was not associated with a significant difference in survival to hospital discharge, neurological outcomes or survival to 3 months. Further research is required to control for the confounders during inpatient management.

Intra-articular Alpha-2 Agonists as an Adjunct to Local Anesthetic in Knee Arthroscopy: A Systematic Review and Meta-Analysis.

The infiltration of local anesthetic has been shown to reduce postoperative pain in knee arthroscopy. Several studies have shown that the addition of agents such as magnesium and nonsteroidal antiinflammatory drugs (NSAIDs) result in an increased time to first analgesia and overall reduction in pain. The aim of this systematic review and meta-analysis was to determine whether the addition of an α-2 agonist (A2A) to intra-articular local anesthetic, results in a reduction in postoperative pain. Four major databases were systematically searched for relevant randomized controlled trials (RCTs) up to July 2017. RCTs containing a control group receiving a local anesthetic and an intervention group receiving the same with the addition of an A2A were included in the review. The included studies were assessed for level of evidence and risk of bias. The data were then analyzed both qualitatively and where appropriate by meta-analysis. We reviewed 12 RCTs including 603 patients. We found that the addition of an A2A resulted in a significant reduction in postoperative pain up to 24 hours. The addition of the A2A increased time to first analgesia request by 258.85 minutes (p < 0.00001). Total 24-hour analgesia consumption was analyzed qualitatively with all included studies showing a significant reduction in total analgesia requirement. Interestingly, none of the studies found an increase in side effects associated with the A2A. This study provides strong evidence for the use of A2As as a means to reduce postoperative pain post arthroscopic knee surgery, without a corresponding increase in side effects.

RETRACTED: Sublingual buprenorphine versus intravenous or intramuscular morphine in acute pain: A systematic review and meta-analysis of randomized control trials.

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article has been retracted at the request of the Authors. The authors have provided a clarification stating that the article does not clearly or fully disclose that it better represents a subset of a previously published manuscript in the British Journal of Anaesthesia (White LD, Hodge A, Vlok R, Hurtado G, Eastern K, Melhuish TM. Efficacy and adverse effects of buprenorphine in acute pain management: systematic review and meta-analysis of randomized controlled trials. (Br J Anaesth. 2018;120:668-678). The papers presented in their meta-analysis are a subset of those in their previous review in the British Journal of Anaesthesia, and do not present additional information beyond their previously published work.

Advanced airway management in out of hospital cardiac arrest: A systematic review and meta-analysis.

OBJECTIVES: To assess the difference in survival and neurological outcomes between endotracheal tube (ETT) intubation and supraglottic airway (SGA) devices used during out-of-hospital cardiac arrest (OHCA). METHODS: A systematic search of five databases was performed by two independent reviewers until September 2018. Included studies reported on (1) OHCA or cardiopulmonary resuscitation, and (2) endotracheal intubation versus supraglottic airway device intubation. Exclusion criteria (1) stimulation studies, (2) selectively included/excluded patients, (3) in-hospital cardiac arrest. Odds Ratios (OR) with random effect modelling was used. Primary outcomes: (1) return of spontaneous circulation (ROSC), (2) survival to hospital admission, (3) survival to hospital discharge, (4) discharge with a neurologically intact state. RESULTS: Twenty-nine studies (n = 539,146) showed that overall, ETT use resulted in a heterogeneous, but significant increase in ROSC (OR = 1.44; 95%CI = 1.27 to 1.63; I2 = 91%; p < 0.00001) and survival to admission (OR = 1.36; 95%CI = 1.12 to 1.66; I2 = 91%; p = 0.002). There was no significant difference in survival to discharge or neurological outcome (p > 0.0125). On sensitivity analysis of RCTs, there was no significant difference in ROSC, survival to admission, survival to discharge or neurological outcome (p > 0.0125). On analysis of automated chest compression, without heterogeneity, ETT provided a significant increase in ROSC (OR = 1.55; 95%CI = 1.20 to 2.00; I2 = 0%; p = 0.0009) and survival to admission (OR = 2.16; 95%CI = 1.54 to 3.02; I2 = 0%; p < 0.00001). CONCLUSIONS: The overall heterogeneous benefit in survival with ETT was not replicated in the low risk RCTs, with no significant difference in survival or neurological outcome. In the presence of automated chest compressions, ETT intubation may result in survival benefits.

Buprenorphine versus Morphine in Paediatric Acute Pain: A Systematic Review and Meta-Analysis.

INTRODUCTION: In lab-based studies, buprenorphine appears to have a ceiling effect on respiratory depression but not on analgesia. There is increasing evidence in adult patients that buprenorphine has no ceiling effect on analgesia or side effects. The aim of this study was to investigate the efficacy and adverse effects of buprenorphine versus morphine in paediatric acute pain. METHODS: A systematic review of five databases was performed until May 2018. Only randomised controlled trials were eligible for inclusion. The outcomes of interest included pain, respiratory depression, nausea, sedation, dizziness, and pruritus. RESULTS: Four randomised controlled trials (n=195) were included. The only outcome measuring analgesic efficacy was time to breakthrough analgesia. Buprenorphine had a significant increase in time to breakthrough analgesia by 114.98 minutes compared to morphine (95% CI = 42.94 to 187.01; I2 = 0; p=0.002). There was no significant difference in the rates of adverse effects. CONCLUSIONS: Buprenorphine provided a longer duration of analgesia than morphine. This in combination with its unique sublingual preparation could prove particularly advantageous in the paediatric population. The studies included are likely underpowered to detect differences in the incidence of adverse effects; therefore, the same precautions should be taken as with any other opioid.

Antiarrhythmics in Cardiac Arrest: A Systematic Review and Meta-Analysis.

INTRODUCTION: It is widely accepted that antiarrhythmics play a role in cardiopulmonary resuscitation (CPR) universally, but the absolute benefit of antiarrhythmic use and the drug of choice in advanced life support remains controversial. AIM: To perform a thorough, in-depth review and analysis of current literature to assess the efficacy of antiarrhythmics in advanced life support. MATERIAL AND METHODS: Two authors systematically searched through multiple bibliographic databases including CINAHL, SCOPUS, PubMed, Web of Science, Medline(Ovid) and the Cochrane Clinical Trials Registry. To be included studies had to compare an antiarrhythmic to either a control group, placebo or another antiarrhythmic in adult cardiac arrests. These studies were independently screened for outcomes in cardiac arrest assessing the effect of antiarrhythmics on return of spontaneous circulation (ROSC), survival and neurological outcomes. Data was extracted independently, compared for homogeneity and level of evidence was evaluated using the Cochrane Collaboration's tool for assessing the risk of bias. The Mantel-Haenszel (M-H) random effects model was used and heterogeneity was assessed using the I2 statistic. RESULTS AND DISCUSSION: The search of the literature yielded 30 studies, including 39,914 patients. Eight antiarrhythmic agents were identified. Amiodarone and lidocaine, the two most commonly used agents, showed no significant effect on any outcome either against placebo or each other. Small low quality studies showed benefits in isolated outcomes with esmolol and bretylium against placebo. The only significant benefit of one antiarrhythmic over another was demonstrated with nifekalant over lidocaine for survival to admission (p=0.003). On sensitivity analysis of a small number of high quality level one RCTs, both amiodarone and lidocaine had a significant increase in survival to admission, with no effect on survival to discharge. CONCLUSIONS: This systematic review and meta-analysis suggests that, based on current literature and data, there has been no conclusive evidence that any antiarrhythmic agents improve rates of ROSC, survival to admission, survival to discharge or neurological outcomes. Given the side effects of some of these agents, we recommend further research into their utility in current cardiopulmonary resuscitation guidelines.

Apnoeic oxygenation during intubation in the intensive care unit: A systematic review and meta-analysis.

Hypoxaemia increases the risk of cardiac arrest and mortality during intubation. The reduced physiological reserve and reduced efficacy of pre-oxygenation in intensive care patients makes their intubation particularly dangerous. Apnoeic oxygenation is a promising means of preventing hypoxaemia in this setting. We sought to ascertain whether apnoeic oxygenation reduces the incidence of hypoxaemia when used during endotracheal intubation in the intensive care unit (ICU). A systematic review of five databases for all relevant studies published up to November 2016 was performed. Eligible studies investigated apnoeic oxygenation during intubation in the ICU, irrespective of design. All studies were assessed for risk of bias and level of evidence. A meta-analysis was performed on all data using Revman 5.3. Six studies including 518 patients were retrieved. The study found level 1 evidence of a significant reduction in the incidence of critical desaturation (RR = 0.69, CI = 0.48-1.00, p = 0.05) and a significant increase in the lowest SpO2 value by 2.83% (CI = 2.28-3.38, p < 0.00001). There was a significant reduction in ICU stay (WMD = -2.89, 95%CI = -3.25 to -2.51, p < 0.00001). There was no significant difference between groups regarding mortality (RR = 0.77, 95%CI = 0.59-1.03, p = 0.08), first pass intubation success (RR = 1.17, 95%CI = 0.67 to 2.03, p = 0.58), arrhythmia during intubation (RR = 0.58, 95%CI = 0.08 to 4.29, p = 0.60), cardiac arrest during intubation (RR = 0.33, 95%CI = 0.01 to 7.84, p = 0.49) and duration of ventilation (WMD = -1.97, 95%CI = -5.89 to 1.95, p = 0.32). Apnoeic oxygenation reduces patient hypoxaemia during intubation performed in the ICU. This meta-analysis found evidence that apnoeic oxygenation may significantly reduce the incidence of critical desaturation and significantly raises the minimum recorded SpO2 in this setting. We recommend apnoeic oxygenation be incorporated into ICU intubation protocol.

Apneic oxygenation during intubation in the emergency department and during retrieval: A systematic review and meta-analysis.

BACKGROUND: Hypoxemia increases the risk of intubation markedly. Such concerns are multiplied in the emergency department (ED) and during retrieval where patients may be unstable, preparation or preoxygenation time limited and the environment uncontrolled. Apneic oxygenation is a promising means of preventing hypoxemia in this setting. AIM: To test the hypothesis that apnoeic oxygenation reduces the incidence of hypoxemia during endotracheal intubation in the ED and during retrieval. METHODS: We undertook a systematic review of six databases for all relevant studies published up to November 2016. Included studies evaluated apneic oxygenation during intubation in the ED and during retrieval. There were no exemptions based on study design. All studies were assessed for level of evidence and risk of bias. The Review Manager 5.3 software was used to perform meta-analysis of the pooled data. RESULTS: Six trials and a total 1822 cases were included for analysis. The study found a significant reduction in the incidence of desaturation (RR=0.76, p=0.002) and critical desaturation (RR=0.51, p=0.01) when apneic oxygenation was implemented. There was also a significant improvement in first pass intubation success rate (RR=1.09, p=0.004). CONCLUSION: Apneic oxygenation may reduce patient hypoxemia during intubation performed in the ED and during retrieval. It also improves intubation first-pass success rate in this setting.