Showing papers in "Canadian Journal of Anaesthesia-journal Canadien D Anesthesie in 2021"
TL;DR: The erector spinae plane (ESP) block is an emerging regional anesthetic technique with significant potential for clinical benefit as discussed by the authors, however, its exact mechanism(s) of action has been much debated.
Abstract: The erector spinae plane (ESP) block is an emerging regional anesthetic technique with significant potential for clinical benefit. Nevertheless, its exact mechanism(s) of action has been much debated. We reviewed the available literature to explore the possible mechanisms of analgesia for the ESP block. These include neural blockade and central inhibition from direct spread of local anesthetic to the paravertebral or epidural space; analgesia mediated by elevated local anesthetic plasma concentrations due to systemic absorption; immunomodulatory effects of local anesthetics; and an effect mediated through the mechanosensory properties of thoracolumbar fascia. Based on evidence from clinical, human cadaveric, animal, and mechanistic laboratory studies, the most probable primary mechanism is a direct effect of local anesthetic via physical spread and diffusion to neural structures in the fascial plane deep to the erector spinae muscles and adjacent tissue compartments. Biological plausibility of this primary mechanism is confirmed by injectate spread to the ventral rami of spinal nerves (though quite variable) in most studies. There is consistent involvement of dorsal rami; epidural spread is a less commonly observed phenomenon. A systemic effect of local anesthetic is also plausible, but unlikely to be a major contributor to clinical analgesic efficacy. The evidence for significant analgesia due to other proposed mechanisms, such as fascia-mediated analgesia or lymphatic spread, are currently limited and thus remain speculative. Understanding the mechanisms of action could assist clinicians in further investigating and refining ESP block performance, with the ultimate goal of optimizing analgesic efficacy and improving postoperative patient outcomes.
130 citations
TL;DR: The second of two articles as discussed by the authors addresses airway evaluation, decision-making, and safe implementation of an airway management strategy when difficulty is anticipated, based on the Canadian Airway Focus Group guidelines.
Abstract: Since the last Canadian Airway Focus Group (CAFG) guidelines were published in 2013, the published airway management literature has expanded substantially. The CAFG therefore re-convened to examine this literature and update practice recommendations. This second of two articles addresses airway evaluation, decision-making, and safe implementation of an airway management strategy when difficulty is anticipated. Canadian Airway Focus Group members, including anesthesia, emergency medicine, and critical care physicians were assigned topics to search. Searches were run in the Medline, EMBASE, Cochrane Central Register of Controlled Trials, and CINAHL databases. Results were presented to the group and discussed during video conferences every two weeks from April 2018 to July 2020. These CAFG recommendations are based on the best available published evidence. Where high-quality evidence is lacking, statements are based on group consensus. Prior to airway management, a documented strategy should be formulated for every patient, based on airway evaluation. Bedside examination should seek predictors of difficulty with face-mask ventilation (FMV), tracheal intubation using video- or direct laryngoscopy (VL or DL), supraglottic airway use, as well as emergency front of neck airway access. Patient physiology and contextual issues should also be assessed. Predicted difficulty should prompt careful decision-making on how most safely to proceed with airway management. Awake tracheal intubation may provide an extra margin of safety when impossible VL or DL is predicted, when difficulty is predicted with more than one mode of airway management (e.g., tracheal intubation and FMV), or when predicted difficulty coincides with significant physiologic or contextual issues. If managing the patient after the induction of general anesthesia despite predicted difficulty, team briefing should include triggers for moving from one technique to the next, expert assistance should be sourced, and required equipment should be present. Unanticipated difficulty with airway management can always occur, so the airway manager should have a strategy for difficulty occurring in every patient, and the institution must make difficult airway equipment readily available. Tracheal extubation of the at-risk patient must also be carefully planned, including assessment of the patient’s tolerance for withdrawal of airway support and whether re-intubation might be difficult.
49 citations
TL;DR: The Canadian Airway Focus Group (CAFG) as mentioned in this paper re-convened to examine the literature on airway management in an unconscious patient and provide guidelines for tracheal intubation and supraglottic airway placement.
Abstract: Since the last Canadian Airway Focus Group (CAFG) guidelines were published in 2013, the literature on airway management has expanded substantially. The CAFG therefore re-convened to examine this literature and update practice recommendations. This first of two articles addresses difficulty encountered with airway management in an unconscious patient. Canadian Airway Focus Group members, including anesthesia, emergency medicine, and critical care physicians, were assigned topics to search. Searches were run in the Medline, EMBASE, Cochrane Central Register of Controlled Trials, and CINAHL databases. Results were presented to the group and discussed during video conferences every two weeks from April 2018 to July 2020. These CAFG recommendations are based on the best available published evidence. Where high-quality evidence was lacking, statements are based on group consensus. Most studies comparing video laryngoscopy (VL) with direct laryngoscopy indicate a higher first attempt and overall success rate with VL, and lower complication rates. Thus, resources allowing, the CAFG now recommends use of VL with appropriately selected blade type to facilitate all tracheal intubations. If a first attempt at tracheal intubation or supraglottic airway (SGA) placement is unsuccessful, further attempts can be made as long as patient ventilation and oxygenation is maintained. Nevertheless, total attempts should be limited (to three or fewer) before declaring failure and pausing to consider “exit strategy” options. For failed intubation, exit strategy options in the still-oxygenated patient include awakening (if feasible), temporizing with an SGA, a single further attempt at tracheal intubation using a different technique, or front-of-neck airway access (FONA). Failure of tracheal intubation, face-mask ventilation, and SGA ventilation together with current or imminent hypoxemia defines a “cannot ventilate, cannot oxygenate” emergency. Neuromuscular blockade should be confirmed or established, and a single final attempt at face-mask ventilation, SGA placement, or tracheal intubation with hyper-angulated blade VL can be made, if it had not already been attempted. If ventilation remains impossible, emergency FONA should occur without delay using a scalpel-bougie-tube technique (in the adult patient). The CAFG recommends all institutions designate an individual as “airway lead” to help institute difficult airway protocols, ensure adequate training and equipment, and help with airway-related quality reviews.
43 citations
TL;DR: In a small sample, prone positioning non-intubated COVID-19 patients with severe hypoxemia was safe; however, many patients did not tolerate prolonged durations and many still required intubation.
Abstract: Prone positioning of non-intubated patients with coronavirus disease (COVID-19) and hypoxemic respiratory failure may prevent intubation and improve outcomes. Nevertheless, there are limited data on its feasibility, safety, and physiologic effects. The objective of our study was to assess the tolerability and safety of awake prone positioning in COVID-19 patients with hypoxemic respiratory failure. This historical cohort study was performed across four hospitals in Calgary, Canada. Included patients had suspected COVID-19 and hypoxic respiratory failure requiring intensive care unit (ICU) consultation, and underwent awake prone positioning. The duration, frequency, tolerability, and adverse events from prone positioning were recorded. Respiratory parameters were assessed before, during, and after prone positioning. The primary outcome was the tolerability and safety of prone positioning. Seventeen patients (n = 12 ICU, n = 5 hospital ward) were included between April and May 2020. The median (range) number of prone positioning days was 1 (1–7) and the median number of sessions was 2 (1–6) per day. The duration of prone positioning was 75 (30–480) min, and the peripheral oxygen saturation was 91% (84–95) supine and 98% (92–100) prone. Limitations to prone position duration were pain/general discomfort (47%) and delirium (6%); 47% of patients had no limitations. Seven patients (41%) required intubation and two patients (12%) died. In a small sample, prone positioning non-intubated COVID-19 patients with severe hypoxemia was safe; however, many patients did not tolerate prolonged durations. Although patients had improved oxygenation and respiratory rate in the prone position, many still required intubation. Future studies are required to determine methods to improve the tolerability of awake prone positioning and whether there is an impact on clinical outcomes.
40 citations
TL;DR: In this paper, a dedicated Mobile Endotracheal Rapid Intubation Team (MERIT) was formed to ensure that a highly skilled team would be deployed to manage the airways of this cohort of patients.
Abstract: Because of the anticipated surge in cases requiring intensive care unit admission, the high aerosol-generating risk of tracheal intubation, and the specific requirements in coronavirus disease (COVID-19) patients, a dedicated Mobile Endotracheal Rapid Intubation Team (MERIT) was formed to ensure that a highly skilled team would be deployed to manage the airways of this cohort of patients. Here, we report our intubation team experience and activity as well as patient outcomes during the COVID-19 pandemic. The MERIT members followed a protocolized early tracheal intubation model. Over a seven-week period during the peak of the pandemic, prospective data were collected on MERIT activity, COVID-19 symptoms or diagnosis in the team members, and demographic, procedural, and clinical outcomes of patients. We analyzed data from 150 primary tracheal intubation episodes, with 101 (67.3%) of those occurring in men, and with a mean (standard deviation) age of 55.7 (13.8) yr. Black, Asian, and minority ethnic groups accounted for 55.7% of patients. 91.3% of tracheal intubations were performed with videolaryngoscopy, and the first pass success rate was 88.0%. The 30-day survival was 69.2%, and the median [interquartile range] length of critical care stay was 11 [6–20] days and of hospital stay was 12 [7–22] days. Seven (11.1%) MERIT healthcare professionals self-isolated because of COVID-19 symptoms, with a total 41 days of clinical work lost. There was one reported incident of a breach of personal protective equipment and multiple anecdotal reports of doffing breaches. We have shown that a highly skilled designated intubation team, following a protocolized, early tracheal intubation model may be beneficial in improving patient and staff safety, and could be considered by other institutions in future pandemic surges.
34 citations
TL;DR: In this mannequin-based simulation study, the use of the aerosol box increased the time to intubation in some contexts but not others, and further studies in a clinical setting should be conducted to make appropriate modifications to the aerosoli box to fully elicit its efficacy and safety.
Abstract: Patients with coronavirus disease (COVID-19) are at risk of requiring mechanical ventilation, and concerns of protecting healthcare workers during aerosol-generating medical procedures has led to the design of the aerosol box. We conducted a randomized crossover mannequin-based simulation study to compare airway management with and without the aerosol box. Thirty-five anesthesiology participants and three critical care participants with more than 50 intubations with videolaryngoscopes were recruited. There were four airway simulations with and without the aerosol box (normal, pharyngeal swelling, cervical spine rigidity, and tongue edema). Each participant intubated the mannequin in eight consecutive simulations. The primary outcome of the study was time to intubation. Secondary outcomes included intubation attempts, optimization maneuvers, and personal protective equipment breaches. Mean (standard deviation [SD]) time to intubation overall with the box was 30.9 (23.0) sec, while the time to intubation without the box was 25.1 (12.2) sec (mean difference, 5.8; 95% confidence interval [CI], −2.9 to 14.5). For the normal airway scenario, the mean (SD) time to intubation was 18.6 (3.5) sec for no box and 20.4 (3.3) sec for box (mean difference, 1.8; 95% CI, 0.2 to 3.4). During difficult airway scenarios only, the time to intubation was 34.4 (25.6) sec with the aerosol box and 27.3 (13.2) sec without the aerosol box (mean difference, 7.1; 95% CI, −2.5 to 16.7). There were more intubation attempts, personal protective equipment breaches, and optimization maneuvers during use of the aerosol box. In this mannequin-based simulation study, the use of the aerosol box increased the time to intubation in some contexts but not others. Further studies in a clinical setting should be conducted to make appropriate modifications to the aerosol box to fully elicit its efficacy and safety prior to implementation in airway guidelines for managing patients with COVID-19.
30 citations
TL;DR: In this article, the effect of a high flow nasal oxygen (HFNO) delivery system on oxygenation in this procedure compared with that of conventional nasal cannula oxygen administration was investigated.
Abstract: Deep sedation for endoscopic retrograde cholangiopancreatography (ERCP) can be challenging in elderly patients in the prone position. This study investigated the effect of a high flow nasal oxygen (HFNO) delivery system on oxygenation in this procedure compared with that of conventional nasal cannula oxygen administration. A prospective randomized trial was conducted using HFNO and conventional nasal cannula in patients undergoing ERCP in the prone position. For each patient, the lowest oxygen saturation (SpO2), the incidence of hypoxemia defined as an SpO2 below 90%, and interruptions due to airway interventions were recorded during the procedure. The lowest mean (standard deviation) SpO2 recorded during the procedure was higher in the HFNO group than in the conventional control group [99.8 (0.6)% vs 95.1 (7.3)%; mean difference, 4.7%; 95% confidence interval, 2.3% to 7.1%; P Group x Time < 0.001]. While the lowest SpO2 during the procedure was lower than the baseline SpO2 in the control group, the lowest SpO2 during the procedure was higher than the baseline SpO2 in the HFNO group. Hypoxemia occurred only in the control group (n = 7; 19%; P = 0.01). Procedural interruptions, including discontinuation of sedation, patient stimulation, and jaw thrusting, occurred only in the control group (n = 9 [25%], n = 10 [28%], and n = 10 [28%] cases, respectively; P = 0.001 for each). In contrast to conventional nasal cannula, high flow nasal oxygen provided adequate oxygenation without causing procedural interruptions during ERCP, suggesting that HFNO may be used as a standard oxygen delivery method during these procedures. www.ClinicalTrials.gov
(NCT03872674); registered 11 March 2019.
27 citations
TL;DR: In response to the rapid spread of SARS-CoV-2, hospitals in Canada enacted temporary visitor restrictions to limit the spread of COVID-19 and preserve personal protective equipment supplies as mentioned in this paper.
Abstract: In response to the rapid spread of SARS-CoV-2, hospitals in Canada enacted temporary visitor restrictions to limit the spread of COVID-19 and preserve personal protective equipment supplies. This study describes the extent, variation, and fluctuation of Canadian adult intensive care unit (ICU) visitation policies before and during the first wave of the COVID-19 pandemic. We conducted an environmental scan of Canadian hospital visitation policies throughout the first wave of the pandemic. We conducted a two-phased study analyzing both quantitative and qualitative data. We collected 257 documents with reference to visitation policies (preCOVID, 101 [39%]; midCOVID, 71 [28%]; and lateCOVID, 85 [33%]). Of these 257 documents, 38 (15%) were ICU-specific and 70 (27%) referenced the ICU. Most policies during the midCOVID/lateCOVID pandemic period allowed no visitors with specific exceptions (e.g., end-of-life). Framework analysis revealed five overarching themes: 1) reasons for restricted visitation policies; 2) visitation policies and expectations; 3) exceptions to visitation policy; 4) patient and family-centred care; and 5) communication and transparency. During the first wave of the COVID-19 pandemic, most Canadian hospitals had public-facing visitor restriction policies with specific exception categories, most commonly for patients at end-of-life, patients requiring assistance, or COVID-19 positive patients (varying from not allowed to case-by-case). Further studies are needed to understand the consistency with which visitation policies were operationalized and how they may have impacted patient- and family-centred care.
25 citations
TL;DR: A consensus statement for basic POCUS (bPOCUS) performance and training is developed with a group of national experts from all Canadian universities to define a Canadian national standard on which curricula may be based and provide a framework to allow further development of bPOC US in the perioperative setting.
Abstract: Point-of-care ultrasound (POCUS) uses ultrasound at the bedside to aid decision-making in acute clinical scenarios. The increased use of ultrasound for regional anesthesia and vascular cannulation, together with more anesthesiologists trained in transesophageal echocardiography have contributed to the widespread use of POCUS in perioperative care. Despite the support of international experts, the practice of POCUS in perioperative care is variable as Canadian guidelines for anesthesiologists do not currently exist. Using a Delphi process of online surveys and a face-to-face national Canadian meeting, we developed a consensus statement for basic POCUS (bPOCUS) performance and training with a group of national experts from all Canadian universities. The group of experts consisted of 55 anesthesiologists from 12 Canadian universities considered local leaders in the field. An initial exploratory online survey of 47 statements was conducted. These statements were derived from previous generic guidelines or consensus conferences, or were based on current literature. Fourteen statements reached full consensus, 19 had 90-100% agreement, and 14 had less than 90% agreement. Eight new statements were proposed during the national meeting, and all statements without full agreement were discussed. A second online survey included 42 modified or new statements. From this second survey, 16 statements obtained full consensus, 39 had very good agreement, and one had good agreement. The final document includes 56 statements that define the scope of practice and necessary training for perioperative bPOCUS. The statements include five bPOCUS domains: cardiac, lung, airway, gastric, and abdomen. The use of bPOCUS is evolving and will play a significant role in perioperative medicine. This consensus statement aims to define a Canadian national standard on which curricula may be based. It also provides a framework to allow further development of bPOCUS in the perioperative setting.
20 citations
TL;DR: The findings support the continued need for adoption, adherence, and practice of guidelines for anticipated and unanticipated difficult airway management for every patient encounter.
Abstract: We analyzed closed civil legal cases in 2007-2016 from the Canadian Medical Protective Association (CMPA) involving specialist anesthesiologists where airway management was the central concern. We included all airway-related civil legal cases involving specialist anesthesiologists that closed from 2007 to 2016. The following variables were abstracted by CMPA medical analysts: clinical context, peer expert opinions of contributing factors, and patient and legal outcomes. We found 46 of the 406 (11%) closed cases involving anesthesiologists to be airway-related. Twenty-six cases (57%) involved elective surgery and 31 patients (67%) were categorized as American Society of Anesthesiologists physical status III. Twenty-five cases (54%) occurred outside the operating room (e.g., postanesthesia care unit, intensive care unit, or other satellite locations). In 19 (42%) cases, there was at least one predictor of a difficult airway. Peer experts identified judgement failures in 30 cases (65%), most commonly inadequate airway evaluation. In 30 cases (65%), the patient died or had a permanent brain injury. The medicolegal outcome favoured the patient in 27 (59%) cases, with a median [interquartile range] payment of 422,845 [257,637-935,673] CAD. Severe patient harm is common when airway management is the focus of a CMPA medicolegal complaint involving anesthesiologists. Patients were otherwise typically low risk cases presenting for elective surgery. Failure to assess or to change management based on the airway exam or encountered difficulty were the most common errors. Our findings support the continued need for adoption, adherence, and practice of guidelines for anticipated and unanticipated difficult airway management for every patient encounter.
20 citations
TL;DR: In this cohort, pain intensity and pain-related interference scores were reduced and QoL and general health symptoms scores were improved compared with baseline, and female sex was significantly associated with worse outcomes than male sex.
Abstract: We investigated patients with chronic pain seeking medical cannabis. We assessed their demographics, patterns of cannabis use, and the long-term effectiveness of cannabis on their pain and functional domains. This observational study enrolled patients between 8 September 2015 and 31 July 2018 from community-based cannabis clinics in Ontario, Canada. In addition to collecting demographic information, the primary outcomes studied were pain intensity and pain-related interference scores assessed at baseline, three, six, and 12 months. Using validated questionnaires, we also assessed anxiety, depression, quality of life (QoL), general health symptoms, neuropathic pain, self-reported opioid consumption, and adverse events. Of the 1,000 patients consented, 757 (76%) participated at one or more of the study time points. At six and 12 months, 230 (30.4%) and 104 (13.7%) of participants were followed up, respectively. Most participants were female (62%), Caucasian (91%), and sought cannabis for pain relief (88%). Time was a significant factor associated with improvement in pain intensity (P < 0.001), pain-related interference scores (P < 0.001), QoL (P < 0.001), and general health symptoms (P < 0.001). Female sex was significantly associated with worse outcomes than male sex including pain intensity (P < 0.001) and pain-related interference (P < 0.001). The proportion of individuals who reported using opioids decreased by half, from 40.8% at baseline to 23.9% at 12 months. Despite significant challenges to collecting long-term observational data on patients who attempted a trial of cannabis products, approximately one-third of patients in the cohort remained on medical cannabis for six months. In this cohort, pain intensity and pain-related interference scores were reduced and QoL and general health symptoms scores were improved compared with baseline.
TL;DR: In this paper, the practical pharmacology of tranexamic acid and its clinical use in trauma, obstetrics, and major orthopedic surgery are reviewed and evaluated.
Abstract: In this Continuing Professional Development module, we review the practical pharmacology of tranexamic acid and its clinical use in trauma, obstetrics, and major orthopedic surgery. Tranexamic acid is a synthetic drug that inhibits fibrinolysis. Multiple clinical trials in various clinical settings have shown that it can reduce blood loss, transfusion rates, and bleeding-associated mortality. In trauma and obstetrical bleeding, early tranexamic acid administration (< three hours) may have greater clinical benefits. Overall, tranexamic acid use appears safe with no significant increase of thromboembolic or seizure events. Nevertheless, current evidence has limitations related to wide heterogeneity in dose, route, and timing of drug administration, as well as generalizability of the large-scale trial findings to higher income nations. Tranexamic acid is an efficacious and safe pharmacological-based blood conservation technique in the management of clinically significant hemorrhage. All anesthesiologists should have a good understanding of the pharmacotherapeutic properties and perioperative role of tranexamic acid therapy both inside and outside of the operating room. The use of tranexamic acid is likely to continue to rise with endorsement by various clinical guidelines and healthcare organizations. Further quantitative research is needed to evaluate optimal dosing and drug efficacy in these clinical scenarios.
TL;DR: In this paper, the Alberta provincial prone positioning strategy during the COVID-19 pandemic or future respiratory pandemics was reviewed and discussed. But, the use of prone positioning was not considered for all patients with moderate to severe ARDS.
Abstract: Many patients with coronavirus disease (COVID-19) will develop acute respiratory distress syndrome (ARDS). Prone positioning is an important non-pharmacologic strategy that should be considered for all invasively ventilated patients with moderate to severe ARDS (including those with COVID-19). Prone positioning offers several physiologic and clinical benefits, including improving hypoxemia, matching ventilation with perfusion, reducing regional hyperinflation, and improving survival. To safely offer prone positioning, appropriate training, simulation, and health system planning should be undertaken. In this review, we offer ten tips, based on the Alberta provincial prone positioning strategy during COVID-19, to safely implement and improve the appropriate use of prone positioning. We provide special considerations for its use during the COVID-19 pandemic or future respiratory pandemics.
TL;DR: An increased physiologic dead space is found in the intensive care unit of Hôpital du Sacré-Coeur de Montréal, supporting the hypothesis that pulmonary vascular injury may be central to COVID-19-induced lung damage.
Abstract: Montreal has been the epicentre of the coronavirus disease (COVID-19) pandemic in Canada. Given the regional disparities in incidence and mortality in the general population, we aimed to describe local characteristics, treatments, and outcomes of critically ill COVID-19 patients in Montreal. A single-centre retrospective cohort of consecutive adult patients admitted to the intensive care unit (ICU) of Hopital du Sacre-Coeur de Montreal with confirmed COVID-19 were included. Between 20 March and 13 May 2020, 75 patients were admitted, with a median [interquartile range (IQR)] age of 62 [53–72] yr and high rates of obesity (47%), hypertension (67%), and diabetes (37%). Healthcare-related infections were responsible for 35% of cases. The median [IQR] day 1 sequential organ failure assessment score was 6 [3–7]. Invasive mechanical ventilation (IMV) was used in 57% of patients for a median [IQR] of 11 [5–22] days. Patients receiving IMV were characterized by a moderately decreased median [IQR] partial pressure of oxygen:fraction of inspired oxygen (day 1 PaO2:FiO2 = 177 [138–276]; day 10 = 173 [147–227]) and compliance (day 1 = 48 [38–58] mL/cmH2O; day 10 = 34 [28–42] mL/cmH2O) and very elevated estimated dead space fraction (day 1 = 0.60 [0.53–0.67]; day 10 = 0.72 [0.69–0.79]). Overall hospital mortality was 25%, and 21% in the IMV patients. Mortality was 82% in patients ≥ 80 yr old. Characteristics and outcomes of critically ill patients with COVID-19 in Montreal were similar to those reported in the existing literature. We found an increased physiologic dead space, supporting the hypothesis that pulmonary vascular injury may be central to COVID-19-induced lung damage.
TL;DR: In this paper, the authors performed a systematic review and meta-analysis of observational studies and randomized controlled trials comparing PAC vs no PAC in cardiogenic shock and found that PAC was associated with improved survival to hospital discharge (relative risk, 0.77; 95% confidence interval [CI], 0.64 to 0.87; I2 = 99%; very low-quality evidence).
Abstract: Cardiogenic shock carries high morbidity and mortality. The purpose of this review was to determine the safety and efficacy of pulmonary artery catheterization (PAC) in adult patients hospitalized with cardiogenic shock. We performed a systematic review and meta-analysis of observational studies and randomized controlled trials comparing PAC vs no PAC in cardiogenic shock. We searched MEDLINE, EMBASE, Cochrane CENTRAL, and grey literature. We screened articles, abstracted data, and evaluated risk of bias in duplicate. We pooled data using a random-effects model and evaluated the quality of evidence using the GRADE framework. Outcomes of interest were mortality, length of stay, and procedural complications. We identified 19 eligible observational studies (≥ 2,716,287 patients) and no randomized controlled trials; 14 studies were at high risk of bias (lack of adjustment for prognostic variables and/or co-interventions). When pooling adjusted results, PAC was associated with improved survival to hospital discharge (relative risk [RR], 0.77; 95% confidence interval [CI], 0.64 to 0.91, I2 = 98%; very low-quality evidence) and at longest available follow-up (RR, 0.72; 95% CI, 0.60 to 0.87; I2 = 99%; very low-quality evidence). Unadjusted length of stay was 3.5 days longer (95% CI, 1.49 to 5.54; I2 = 100%; very low-quality evidence) with PAC. Procedural complications were inconsistently reported. Very low-quality observational evidence suggests PAC use in patients with cardiogenic shock is associated with lower mortality. Overall, these results support consideration of PAC for hemodynamic assessment in cardiogenic shock. Prospective randomized clinical trials are needed to further characterize the role of PAC in this population.
TL;DR: It is found that significant case-by-case variation exists for all methods of blood loss evaluation and that there is significant disagreement between techniques.
Abstract: Estimated blood loss (EBL) is an important tool in clinical decision-making and surgical outcomes research. It guides perioperative transfusion practice and serves as a key predictor of short-term perioperative risks and long-term oncologic outcomes. Despite its widespread clinical and research use, there is no gold standard for blood loss estimation. We sought to systematically review and compare techniques for intraoperative blood loss estimation in major non-cardiac surgery with the objective of informing clinical estimation and research standards. A structured search strategy was applied to Ovid Medline, Embase, and Cochrane Library databases from inception to March 2020, to identify studies comparing methods of intraoperative blood loss in adult patients undergoing major non-cardiac surgery. We summarized agreement between groups of pairwise comparisons as visual estimation vs formula estimation, visual estimation vs other, and formula estimation vs other. For each of these comparisons, we described tendencies for higher or lower EBL values, consistency of findings, pooled mean differences, standard deviations, and confidence intervals. We included 26 studies involving 3,297 patients in this review. We found that visual estimation is the most frequently studied technique. In addition, visual techniques tended to provide lower EBL values than formula-based estimation or other techniques, though this effect was not statistically significant in pooled analyses likely due to sample size limitations. When accounting for the contextual mean blood loss, similar case-to-case variation exists for all estimation techniques. We found that significant case-by-case variation exists for all methods of blood loss evaluation and that there is significant disagreement between techniques. Given the importance placed on EBL, particularly for perioperative prognostication models, clinicians should consider the universal adoption of a practical and reproducible method for blood loss evaluation. PROSPERO (CRD42015029439); registered: 18 November 2015.PROSPERO (CRD42015029439); registered: 18 November 2015.
TL;DR: In this article, the effect of subanesthetic-dose ketamine as an adjunct to desflurane anesthesia on natural killer (NK) cell activity and inflammation in patients undergoing colorectal cancer surgery was investigated.
Abstract: Ketamine’s inhibitory action on the N-methyl-d-aspartate receptor and anti-inflammatory effects may provide beneficial immunomodulation in cancer surgery. We investigated the effect of subanesthetic-dose ketamine as an adjunct to desflurane anesthesia on natural killer (NK) cell activity and inflammation in patients undergoing colorectal cancer surgery. A total of 100 patients were randomly assigned to a control or ketamine group. The ketamine group received a bolus of 0.25 mg·kg−1 ketamine five minutes before the start of surgery, followed by an infusion 0.05 mg·kg−1·hr−1 until the end of surgery; the control group received a similar amount of normal saline. We measured NK cell activity and proinflammatory cytokines (interleukin-6 [IL-6] and tumour necrosis factor-α [TNF-α]) before surgery and one, 24, and 48 hr after surgery. C-reactive protein (CRP) was measured before surgery and one, three, and five days after surgery. Carcinoembryonic antigen and cancer recurrence/metastasis were assessed two years after surgery. The NK cell activity was significantly decreased after surgery in both groups, but the change was not different between groups in the linear mixed model analysis (P = 0.47). Changes in IL-6, TNF-α, CRP, and carcinoembryonic antigen levels were not different between groups (P = 0.27, 0.69, 0.99, and 0.97, respectively). Cancer recurrence within 2 years after surgery was similar between groups (10% vs 8%, P = 0.62). Intraoperative low-dose ketamine administration did not convey any favourable impacts on overall postoperative NK cell activity, inflammatory responses, and prognosis in colorectal cancer surgery patients. www.clinicaltrial.gov
(NCT03273231); registered 6 September 2017.
TL;DR: Pupillometry is a technique for objective quantification of nociception that takes into account the central processing of noxious stimuli and its sympathetic response as discussed by the authors, which has the potential to personalize pain management in perioperative and intensive care unit environments.
Abstract: Pupillometry is a technique for objective quantification of nociception that takes into account the central processing of noxious stimuli and its sympathetic response. This narrative review provides an overview of the physiology of the pupil, the principles of pupillometry, and its potential application in the perioperative environment, especially in nociception monitoring and quantifying responses to opioids. Relevant articles, including reports of original investigation, review articles, and meta-analyses were identified from searches of PubMed and Google Scholar databases. Articles that described pupillary physiology and pupillometry, along with original research reports of the application of pupillometry in perioperative and critical care environment were used to synthesize a narrative review. Pupillometry is emerging as an objective measure of nociception, especially in patients under general anesthesia, children, non-verbal patients, and critically ill patients who cannot effectively communicate ongoing pain. Portable automated pupillometers have made accurate quantification of pupillary reflexes, including light reflex and dilatation reflex, possible. This technique has been successfully studied in the perioperative setting for a number of applications, including quantification of nociception, response to analgesia, and assessing efficacy of regional blocks. Pupillary oscillations have shown promise in assessing central opioid effects. Pupillometers can also accurately quantify light reflexes during the neurologic evaluation of critically ill patients. Pupillometry is an easy to use non-invasive bedside technique to quantify nociception and monitor opioid effects. It has the potential to personalize pain management in perioperative and intensive care unit environments. Additional studies are needed to further understand the utility of pupillometry in this context.
TL;DR: In this article, the efficacy, efficiency, and safety of videolaryngoscopy compared with direct LBS in obstetrics were examined. But, they did not examine whether this extends to obstetrical surgery.
Abstract: 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. 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. 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. 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. PROSPERO (CRD42020189521); registered 6 July 2020.
TL;DR: In this paper, a systematic review identified meta-analyses which compared direct Macintosh laryngoscopy to videolaryngoscope blade types, including traditional Macintosh blades and hyperangulated blades.
Abstract: In the preceding 20 years, many randomized-controlled trials and meta-analyses have compared direct Macintosh laryngoscopy with videolaryngoscopy. The videolaryngoscope blades have included both traditional Macintosh blades and hyperangulated blades. Macintosh and hyperangulated blades differ in their geometry and technique for tracheal intubation; certain patient populations may benefit from one blade type over another. The primary objective of this systematic review was to assess whether published meta-analyses comparing direct Macintosh laryngoscopy to videolaryngoscopy have accounted for the videolaryngoscope blade type. Secondary objectives evaluated heterogeneity among practitioner experience and specialty, clinical context, patient population, and original primary study outcomes. A search was performed across Ovid Medline, Ovid Embase, ClinicalKey, PubMed, TRIP, AccessAnesthesiology, Google Scholar, and ANZCA discovery. A systematic review identified meta-analyses which compared direct Macintosh laryngoscopy to videolaryngoscopy. There were no patient age or clinical specialty restrictions. Exclusion criteria included non-English language, studies comparing non-Macintosh blade to videolaryngoscopy, and studies in awake patients. Twenty-one meta-analyses were identified that were published between 1 January 2000 and 7 May 2020. Macintosh and hyperangulated videolaryngoscope blades were combined in most studies (16/21; 76%). Heterogeneity was also present among practitioner experience (20/21; 95%), clinician specialty (15/21; 71%), and clinical locations (10/21; 48%). Adult and pediatric patients were combined or not defined in 5/21 studies (24%). The primary outcomes of the meta-analyses varied, with the most common (7/21; 33%) being first-pass tracheal intubation success. Heterogeneity across important clinical variables is common in meta-analyses comparing direct Macintosh laryngoscopy to videolaryngoscopy. To better inform patient care, future videolaryngoscopy research should differentiate blade type, clinical context, and patient-related primary outcomes.
TL;DR: Perceptions that requests for continued organ support were driven by mistrust, tensions surrounding decision-making, and cultural differences rather than a lack of specific information about NDD were revealed.
Abstract: Neurologic determination of death (NDD) is legally accepted as death in Canada but remains susceptible to misunderstandings. In some cases, families request continued organ support after NDD. Conflicts can escalate to formal legal challenges, causing emotional, financial, and moral distress for all involved. We describe prevalence, characteristics, and common experiences with requests for continued organ support following NDD in Canada. Mixed-methods design combining anonymous online survey with semi-structured interviews of Canadian critical care physicians (448 practitioners, adult and pediatric). One hundred and six physicians responded to the survey and 12 participated in an interview. Fifty-two percent (55/106) of respondents had encountered a request for continued organ support after NDD within two years, 47% (26/55) of which involved threat of legal action. Requests for continued support following NDD ranged from appeals for time for family to gather before ventilator removal to disagreement with the concept of NDD. Common responses to requests included: consultation with an additional physician (54%), consultation with spiritual services (41%), and delay of one to three days for NDD acceptance (49%). Respondents with prior experience were less likely to recommend ancillary tests (P = 0.004) or consultation with bioethics services (P = 0.004). Qualitative analysis revealed perceptions that requests for continued organ support were driven by mistrust, tensions surrounding decision-making, and cultural differences rather than a lack of specific information about NDD. Family requests for continued somatic support following NDD were encountered by half our sample of Canadian critical care physicians. Mitigation strategies require attention to the multifaceted social contexts surrounding these complex scenarios.
TL;DR: A systematic search of Cochrane Library, MEDLINE, and EMBASE was performed from inception to 9 September 2020 as mentioned in this paper, which comprised the following terms: eosinophils, sepsis, septic shock, and acute respiratory distress syndrome (ARDS).
Abstract: Septic shock and acute respiratory distress syndrome (ARDS) are characterized by a dysregulated immune host response that may respond to steroid therapy. Eosinophils contribute to type 2 inflammation that often responds to steroid therapy; their role in immune dysregulation and outcomes in sepsis and ARDS is unclear. A systematic search of Cochrane Library, MEDLINE, and EMBASE was performed from inception to 9 September 2020. The search comprised the following terms: eosinophils, sepsis, septic shock, and ARDS. Two reviewers independently screened abstracts and texts and extracted data on disease severity and clinical outcomes. Thirty-nine studies were identified: 30 evaluated serum eosinophil count in sepsis, one evaluated eosinophil activity in sepsis, three assessed bronchoalveolar lavage (BAL) eosinophil count in ARDS, four assessed eosinophil activity in ARDS, and one assessed peripheral eosinophil count in ARDS. Eleven studies showed an association between eosinopenia and sepsis, and eight studies found persistent eosinopenia at > 48 hr of intensive care unit admission to predict mortality and readmission in septic patients. Three studies found BAL eosinophil count to be low in ARDS, although one found that levels rose in late-phase ARDS. Three studies found eosinophil activity markers in BAL to be high in ARDS and correlate with ARDS severity. Persistent peripheral eosinopenia is a marker of bacterial sepsis and is independently associated with poor outcomes. Bronchoalveolar lavage eosinophil counts are low in early-phase ARDS, but increase in late-phase ARDS, while elevated markers of eosinophil activity correlate with ARDS severity. Further studies understanding the mechanisms leading to eosinopenia in sepsis and increased eosinophil activity in ARDS are needed.
TL;DR: The effects of prone position procedures in mechanically ventilated patients with COVID-19 related ARDS significantly increased PaO2/FIO2 ratio (95% confidence interval [CI]) and the compliance of the respiratory system was calculated as tidal volume/(plateau pressure minus end-expiratory pressure).
Abstract: To the Editor, During the coronavirus disease (COVID-19) outbreak, patients with severe COVID-19 related acute respiratory distress syndrome (ARDS) were admitted to our tertiary hospital intensive care unit (ICU). The benefits of prone position (PP) on survival have been highlighted in previous ARDS studies. The aim of this study was to report the effects of PP in mechanically ventilated patients with COVID-19 related ARDS. Between 1 March 2020 and 30 April 2020, we prospectively included all patients admitted to our ICU with COVID-19 related acute respiratory failure. COVID19 was diagnosed by real-time reverse transcription polymerase chain reaction (rRT-PCR) test on a nasopharyngeal swab. During this period, 70 patients with confirmed COVID-19 were admitted; 64 (91%) received invasive mechanical ventilation during the course of the disease. They were ventilated with low tidal volume (B 6 mL kg), plateau pressure below 30 cmH2O, low driving pressure (B 15 cmH2O), and positive end-expiratory pressure according to the strategy proposed by the ARDS Network. Patients for whom the ratio of arterial oxygen partial pressure to fractional inspired oxygen (PaO2/FIO2) ratio remained below 150 for 12 hr despite this protective ventilation received at least one 16-hr PP session (flow chart, eFigure in Electronic Supplementary Material [ESM]). All patients were sedated and paralyzed before PP. Respiratory parameters were recorded before and at the end of the first 16-hr PP session. The compliance of the respiratory system (Crs) was calculated as tidal volume/(plateau pressure minus end-expiratory pressure). Ventilator settings were not modified during PP, and FIO2 was adjusted for a target peripheral oxygen saturation (SpO2) of 92%. Our local institutional review board waived the need for written consent and data collection was approved by the French licensing authority (number: PI2020_843_0026). Oral and written information was provided to the patients and their families. All parameters were compared using a Wilcoxon rank-sum test and P\\ 0.05 was considered as significant. Twenty-five patients were analyzed. Clinical data appear in the ESM eTable. Prone position procedures significantly increased PaO2/FIO2 ratio (95% confidence interval [CI]) from 91 (78 to 137) to 124 (97 to 149) mmHg (P = 0.008). Arterial partial pressure of carbon dioxide (PaCO2) remained unchanged [from 49 (42 to 51) to 49 (44 to 57) mmHg; P = 0.55], as did Crs [from 32 (21 to 38) to 32 (23 to 40) mL cmH2O; P = 0.33 (Figure)], plateau pressure [from 28 (25 to 30) to 25 (24 to 29) cmH2O; P = 0.16] and ventilatory ratio [from 2.01 (1.47 to 2.51) to 1.98 (1.42 to 2.46); P = 0.98]. Electronic supplementary material The online version of this article (https://doi.org/10.1007/s12630-020-01844-9) contains supplementary material, which is available to authorized users.
TL;DR: In this paper, the authors conducted a secondary analysis of the 6MWT nested cohort substudy of the Measurement of Exercise Tolerance before Surgery study to determine if 6MWTs distance predicts post-operative complications or death.
Abstract: The six-minute walk test (6MWT) is a simple and valid test for assessing cardiopulmonary fitness. Nevertheless, the relationship between preoperative 6MWT distance and postoperative complications is uncertain. We conducted a secondary analysis of the 6MWT nested cohort substudy of the Measurement of Exercise Tolerance before Surgery study to determine if 6MWT distance predicts postoperative complications or death. This analysis included 545 adults (≥ 40 yr) who were at elevated cardiac risk and had elective inpatient non-cardiac surgery at 15 hospitals in Canada, Australia, and New Zealand. Each participant performed a preoperative 6MWT and was followed for 30 days after surgery. The primary outcome was moderate or severe in-hospital complications. The secondary outcome was 30-day death or myocardial injury. Multivariable logistic regression modelling was used to characterize the adjusted association of 6MWT distance with these outcomes. Seven participants (1%) terminated their 6MWT sessions early because of lower limb pain, dyspnea, or dizziness. Eighty-one (15%) participants experienced moderate or severe complications and 69 (13%) experienced 30-day myocardial injury or death. Decreased 6MWT distance was associated with increased odds of moderate or severe complications (adjusted odds ratio, 1.32 per 100 m decrease; 95% confidence interval, 1.01 to 1.73; P = 0.045). There was no association of 6MWT distance with myocardial injury or 30-day death (non-linear association; P = 0.49). Preoperative 6MWT distance had a modest association with moderate or severe complications after inpatient non-cardiac surgery. Further studies are needed to determine the optimal role of the 6MWT as an objective exercise test for informing preoperative risk stratification.
TL;DR: In this article, the authors measured ambient air absorption (Vresorb) and intra-bronchial pressure (Pairway) into the non-ventilated lung during OLV using double-lumen endotracheal tubes (DL-ETT) and bronchial blockers (BB).
Abstract: Double-lumen endotracheal tubes (DL-ETT) and bronchial blockers (BB) are frequently used to allow one-lung ventilation (OLV) during video-assisted thoracic surgery (VATS). Recently, faster lung collapse has been documented with a BB than with a DL-ETT. The physiologic mechanisms behind this faster collapse remained unknown. We aimed to measure ambient air absorption (Vresorb) and intra-bronchial pressure (Pairway) into the non-ventilated lung during OLV using DL-ETT and BB. Patients undergoing VATS and OLV for lung resection were randomly assigned to have measurements made of Vresorb or Pairway within the non-ventilated lung using either a DL-ETT or BB. Thirty-nine patients were included in the analyses. The mean (standard error of the mean [SEM]) Vresorb was similar in the DL-ETT and BB groups [504 (85) vs 630 (86) mL, respectively; mean difference, 126; 95% confidence interval [CI], -128 to 380; P = 0.31]. The mean (SEM) Pairway became progressively negative in the non-ventilated lung in both the DL-ETT and the BB groups reaching [-20 (5) and -31 (10) cmH2O, respectively; mean difference, -11; 95% CI, -34 to 12; P = 0.44] at the time of the pleural opening. During OLV before pleural opening, entrainment of ambient air into the non-ventilated lung occurs when the lumen of the lung isolation device is kept open. This phenomenon is prevented by occluding the lumen of the isolation device before pleural opening, resulting in a progressive build-up of negative pressure in the non-ventilated lung. Future clinical studies are needed to confirm these physiologic results and their impact on lung collapse and operative outcomes. www.clinicaltrials.gov (NCT02919267); registered 28 September 2016.
TL;DR: While a small percentage of adult patients who underwent ASC procedures required unplanned hospital admission, approximately one-third of these admissions were to the ICU, suggesting facility was at least as strong a predictor of hospital admission as the patient- and/or procedure-specific variables.
Abstract: We estimated the rate of unplanned hospital and intensive care unit (ICU) admissions following ambulatory surgery centre (ASC) procedures, and identified factors associated with their occurrence. This retrospective cohort included adult patients who underwent ASC procedures within a large community practice from January 2010 to December 2014. Patients were categorized into two groups: unplanned postoperative hospital/ICU admission within 24 hr of procedure or uneventful discharge. Demographics, comorbidities, anesthesia type, procedure type, procedure group, and ASC facility were assessed. Of the 211,389 patients included, there were 211,147 uneventful discharges (99.89%) and 242 unplanned hospital admissions (0.11%), of which 75 were ICU admissions (0.04%). The multivariable logistic regression model for hospital admission showed an increased risk associated with age > 50 yr (odds ratio [OR], 1.53); American Society of Anesthesiologists (ASA) physical status (III vs II: OR, 1.45; IV vs II: OR, 1.88), comorbidity (chronic obstructive pulmonary disease: OR, 2.63; diabetes mellitus: OR, 1.62; transient ischemic attack: OR, 2.48) procedure (respiratory: OR, 2.92; digestive: OR, 2.66; musculoskeletal system: OR, 2.53), anesthetic management (general anesthesia [GA] and peripheral nerve block vs GA: OR, 1.79), and ASC facility (189BB: OR, 2.29; 30E9A: OR, 7.41; and BD21F: OR, 1.69). The multivariable logistic regression model for ICU admission showed increased risk of unplanned ICU admission associated with ASA physical status (ASA III vs II: OR, 3.0; ASA IV vs II: OR, 8.52), procedure (musculoskeletal system: OR, 2.45), and ASC facility (00E6C: OR, 3.14; 189BB: OR, 2.77; 30E9A: OR, 2.59; and BD21F: OR, 3.71). While a small percentage of adult patients who underwent ASC procedures required unplanned hospital admission (0.07%), approximately one-third of these admissions were to the ICU (0.04%). Facility was at least as strong a predictor of hospital admission as the patient- and/or procedure-specific variables.
TL;DR: In this article, a consensus building process by a multidisciplinary group of Canadian stakeholders were to review current evidence and international DCD heart experience, comparatively evaluate international protocols with existing Canadian medical, legal, and ethical practices, and to discuss implementation barriers.
Abstract: Controlled donation after circulatory determination of death (DCD), where death is determined after cardiac arrest, has been responsible for the largest quantitative increase in Canadian organ donation and transplants, but not for heart transplants. Innovative international advances in DCD heart transplantation include direct procurement and perfusion (DPP) and normothermic regional perfusion (NRP). After death is determined, DPP involves removal and reanimation of the arrested heart on an ex situ organ perfusion system. Normothermic regional perfusion involves surgically interrupting (ligating the aortic arch vessels) brain blood flow after death determination, followed by restarting the heart and circulation in situ using extracorporeal membrane oxygenation. The objectives of this Canadian consensus building process by a multidisciplinary group of Canadian stakeholders were to review current evidence and international DCD heart experience, comparatively evaluate international protocols with existing Canadian medical, legal, and ethical practices, and to discuss implementation barriers. Review of current evidence and international experience of DCD heart donation (DPP and NRP) determined that DCD heart donation could be used to provide opportunities for more heart transplants in Canada, saving additional lives. Although candid discussion identified a number of potential barriers and challenges for implementing DCD heart donation in Canada, it was determined that DPP implementation is feasible (pending regulatory approval for the use of an ex situ perfusion device in humans) and in alignment with current medical guidelines for DCD. Nevertheless, further work is required to evaluate the consistency of NRP with current Canadian death determination policy and to ensure the absence of brain perfusion during this process.