Identifying behaviors that characterize emergence delirium: An observational study.

BACKGROUND: Diagnostic criteria for emergence agitation are sensitive but not specific; they misclassify patients who are angry or upset as having emergence delirium. AIMS: The aim of this three-phase study was to determine expert agreement on the behaviors that differentiate children with emergence delirium from those without. METHODS: In the first phase of this observational study, pediatric dental patients were video recorded while awakening from anesthesia. In the second phase, salient 10 s segments of the recordings showing patient activity were shown to an expert audience of pediatric dentists, anesthesiologists and Post Anesthetic Care nurses, who scored the recordings as showing or not showing "true emergence delirium." In phase 3, the video segments were assessed by three research assistants using a behavior checklist for features that discriminate between those scored "true emergence delirium" and those scored "NOT true emergence delirium" by the experts. RESULTS: One hundred and fifty-four pediatric dental patients were included. Subsequently, an expert audience consisting of 10 anesthesiologists, 12 anesthesiology residents, 3 pediatric dentists, and 4 experienced Post Anesthesia Care Unit nurses rated each 10-second video segment. This resulted in three groups of patients: a group for whom all experts agreed was "True emergence delirium" (n = 33; CI 21 to 45), a group for whom all agreed was "Not True emergence delirium" (n = 120; CI 107 to 133), and a group where experts disagreed (n = 11; CI 4 to 18). Three research assistants then completed a behavior checklist for each of the 33 "True emergence delirium" video segments and matched "Not True" controls. Twenty-four behaviors were identified as significantly different between videos scored True emergence delirium and those scored Not True emergence delirium. Research assistants reached almost perfect agreement (0.81-1.00) on one behavior, and substantial agreement (0.61-0.80) on seven behaviors that characterized "True emergence delirium." CONCLUSIONS: Eight behaviors that differentiate pediatric dental patients with emergence delirium from those without were found. These discriminators may be used to develop a scale that will lead to better diagnosis and treatment of emergence delirium.

A performance comparison of the most commonly used minimally invasive monitors of cardiac output.

BACKGROUND: Shock is common in critically ill and injured patients. Survival during shock is highly dependent on rapid restoration of tissue oxygenation with therapeutic goals based on cardiac output (CO) optimization. Despite the clinical availability of numerous minimally invasive monitors of CO, limited supporting performance data are available. METHODS: Following approval of the University of Saskatchewan Animal Research Ethics Board, we assessed the performance and trending ability of PiCCOplus™, FloTrac™, and CardioQ-ODM™ across a range of CO states in pigs. In addition, we assessed the ability of invasive mean arterial blood pressure (iMAP) to follow changes in CO using a periaortic transit-time flow probe as the reference method. Statistical analysis was performed with function-fail, bias and precision, percent error, and linear regression at all flow, low-flow (> 1 standard deviation [SD] below the mean), and high-flow (> 1 SD above the mean) CO conditions. RESULTS: We made a total of 116,957 paired CO measurements. The non-invasive CO monitors often failed to provide a CO value (CardioQ-ODM: 40.6% failed measurements; 99% confidence interval [CI], 38.5 to 42.6; FloTrac: 9.6% failed measurements; 99% CI, 8.7 to 10.5; PiCCOplus: 4.7% failed measurements; 99% CI, 4.5 to 4.9; all comparisons, P < 0.001). The invasive mean arterial pressure provided zero failures, failing less often than any of the tested CO monitors (all comparisons, P < 0.001). The PiCCOplus was most interchangeable with the flow probe at all flow states: PiCCOplus (20% error; 99% CI, 19 to 22), CardioQ-ODM (25% error; 99% CI, 23 to 27), FloTrac (34% error; 99% CI, 32 to 38) (all comparisons, P < 0.001). At low-flow states, CardioQ-ODM (43% error; 99% CI, 32 to 63) and Flotrac (45% error; 99% CI, 33 to 70) had similar interchangeability (P = 0.07), both superior to PiCCOplus (48% error; 99% CI, 42 to 60) (P < 0.001). Regarding CO trending, the CardioQ-ODM (correlation coefficient, 0.82; 99% CI, 0.81 to 0.83) was statistically superior to other monitors including iMAP, but at low flows iMAP (correlation coefficient, 0.58; 99% CI, 0.58 to 0.60) was superior to all minimally invasive CO monitors (all comparisons P < 0.001). CONCLUSIONS: None of the minimally invasive monitors of CO performed well at all tested flows. Invasive mean arterial blood pressure most closely tracked CO change at critical flow states.

RéSUMé: CONTEXTE: L'état de choc est fréquent chez les patients blessés et en urgence absolue. La survie pendant le choc dépend fortement de la restauration rapide de l'oxygénation tissulaire avec des objectifs thérapeutiques basés sur l'optimisation du débit cardiaque (DC). Malgré la disponibilité clinique de nombreux moniteurs minimalement invasifs du DC, il n'existe que des données limitées sur leur performance pour appuyer leur utilisation. MéTHODE: À la suite de l'approbation du comité d'éthique de la recherche animale de l'Université de la Saskatchewan, nous avons évalué la performance et la capacité de suivi des tendances des appareils PiCCOplus™, FloTrac™ et CardioQ-ODM™ sur une vaste gamme d'état de DC chez des cochons. Nous avons également évalué la capacité de la tension artérielle moyenne invasive (iMAP) à suivre les changements de DC en utilisant une sonde périaortique de débit basée sur le temps de transit comme méthode de référence. L'analyse statistique a été réalisée avec fonction-échec, biais et précision, pourcentage d'erreur et régression linéaire à des conditions de DC de tous les débits, de faible débit (> 1 écart-type [ET] au-dessous de la moyenne) et de débit élevé (> 1 ET au-dessus de la moyenne). RéSULTATS: Nous avons effectué un total de 116 957 mesures de DC appariées. Les moniteurs non invasifs de la DC n'ont souvent pas réussi à fournir une valeur de DC (CardioQ-ODM : 40,6% de mesures échouées; intervalle de confiance [IC] de 99 %, 38,5 à 42,6; FloTrac : 9,6 % de mesures échouées; IC 99 %, 8,7 à 10,5; PiCCOplus : 4,7 % de mesures échouées; IC 99 %, 4,5 à 4,9; toutes les comparaisons, P < 0,001). La tension artérielle moyenne invasive n'a fourni aucun échec plus souvent que n'importe lequel des moniteurs de DC testés (toutes les comparaisons, P < 0,001). Le PiCCOplus était le plus interchangeable avec la sonde de débit à tous les états de débit : PiCCOplus (erreur de 20 %; IC 99 %, 19 à 22), CardioQ-ODM (erreur de 25 %; IC 99 %, 23 à 27), FloTrac (erreur de 34 %; IC 99 %, 32 à 38) (toutes les comparaisons, P < 0,001). Aux états de débit faible, les moniteurs CardioQ-ODM (erreur de 43 %; IC 99 %, 32 à 63) et FloTrac (erreur de 45 %; IC 99 %, 33 à 70) présentaient une interchangeabilité similaire (P = 0,07), tous deux supérieurs au PiCCOplus (erreur de 48 %; IC 99 %, 42 à 60) (P < 0,001). En ce qui concerne le suivi des tendances de DC, le CardioQ-ODM (coefficient de corrélation, 0,82; IC 99 %, 0,81 à 0,83) était statistiquement supérieur aux autres moniteurs, y compris au iMAP, mais à faibles débits, l'iMAP (coefficient de corrélation, 0,58; IC 99 %, 0,58 à 0,60) était supérieure à tous les moniteurs de DC minimalement invasifs (toutes les comparaisons, P < 0,001). CONCLUSION: Aucun des moniteurs de DC minimalement invasif n'a donné de bons résultats à tous les débits testés. La tension artérielle moyenne invasive était le moniteur qui a suivi de plus près les changements de DC dans des états critiques de débit.

A comparison of methods used to secure pediatric endotracheal tubes using a live human dermal model.

BACKGROUND: Endotracheal intubation is a common lifesaving procedure. An in situ endotracheal tube (ETT) must be secured in position to avoid displacement and potentially life-threatening complications. Adhesive tapes form the most common intraoperative ETT stabilization methods. Limited published data are available to guide the clinical decision regarding ETT taping method. We performed an interventional study aiming to establish which of many commonly employed ETT tape/supplementary adhesive methods provides the most resistance to ETT distraction. METHODS: An experiment was undertaken to measure the force required to distract an ETT secured to a live dermal model with 24 different ETT securing methods comprising six types of tape alone and in combination with one of three supplementary adhesives. The primary measurement was the peak force (Newtons) required to distract a secured ETT 3 cm. RESULTS: A total of 1,164 measurements were made. The mean force required to distract the ETT ranged from 7.8 to 21.8 Newtons. The combination of Cloth Adhesive™ + Mastisol® had the greatest observed mean distraction force, as well as the greatest estimated lower and upper confidence limits. CONCLUSIONS: There are significant differences in force required to distract an ETT based on taping methods.

RéSUMé: CONTEXTE: L'intubation endotrachéale est une intervention critique courante. Le tube endotrachéal (TET) in situ doit être fixé en position adéquate pour éviter qu'il ne se déplace et provoque des complications potentiellement fatales. Les bandes adhésives sont la méthode de stabilisation peropératoire de TET la plus fréquemment utilisée. Il n'existe que peu de données publiées pour guider la décision clinique quant à la méthode de fixation du TET. Nous avons réalisé une étude interventionnelle visant à établir laquelle des nombreuses méthodes couramment employées de bandes adhésives ou de méthodes adhésives supplémentaires du TET procurait la meilleure protection contre un déplacement du TET. MéTHODE: Une expérience a été menée pour mesurer la force nécessaire à déplacer/déloger un TET fixée à un modèle de derme vivant avec 24 méthodes différentes de sécurisation du TET, comprenant six types de ruban adhésif seuls et en combinaison avec l'un de trois adhésifs supplémentaires. La mesure principale était la force maximale (en newton) nécessaire pour déplacer un TET sécurisée de 3 cm. RéSULTATS: Au total, 1164 mesures ont été effectuées. La force moyenne requise pour déplacer le TET allait de 7,8 à 21,8 newtons. La combinaison du ruban Cloth Adhesive™ + Mastisol® a entraîné la plus grande force de déplacement moyenne observée, ainsi que les plus grandes limites inférieure et supérieure estimées des intervalles de confiance. CONCLUSION: Il existe des différences significatives dans la force nécessaire pour déplacer un TET en fonction des méthodes de fixation utilisées.

Transfusion Use and Hemoglobin Levels by Blood Conservation Method After Cardiopulmonary Bypass.

BACKGROUND: Guidelines recommend modified ultrafiltration (MUF) and cell washing for blood conservation after cardiopulmonary bypass (CPB), although information on outcomes is lacking. This research compared online MUF (ultrafiltration of the patient's entire circulating volume) with off-line MUF (ultrafiltration of the residual CPB volume) and centrifugation (cell washing of the residual CPB volume). METHODS: This prospective cohort study enrolled 99 consecutive patients, grouped by method (group I, online MUF, n = 35; group II, off-line MUF, n = 30; group III, centrifugation, n = 34). Primary outcome was transfusion by 18 hours. Secondary outcomes were 18-hour hemoglobin levels, fluid balance (weight change), and biomarker levels indicating coagulation and organ function. RESULTS: By 18 hours, 22.9%, 6.7%, and 14.7% of group I, II, and III patients, respectively, had undergone transfusion (P = .19). Percentage weight gain differed by group (group I, 5.7%; group II, 1.3%; group III, 4.5%; P < .0001). Baseline to 18-hour hemoglobin change also differed by group, with the group I increase significantly exceeding that of group II (P = .002) but not differing from group III (P = .36). After adjustment for European System for Cardiac Operative Risk Evaluation II (EuroSCORE), weight gain, and transfusion, only the group II to III difference remained significant (P = .002). CONCLUSIONS: Online MUF does not appear to offer a reduction in blood transfusion over other methods. Although patients undergoing online MUF had greater improvement in baseline to 18-hour hemoglobin compared with patients undergoing off-line MUF, this benefit appeared attributable to fluid shifting. Off-line MUF was associated with the least frequent transfusions. Although online MUF does not appear to reduce blood transfusion, larger prospective randomized controlled studies are required for confirmation.

Preoperative oral methadone for postoperative pain in patients undergoing cardiac surgery: A randomized double-blind placebo-controlled pilot.

Background: Inadequately controlled sternotomy pain after cardiac surgery can lead to delayed recovery and patient suffering. Preoperative intravenous methadone is effective for reducing both postoperative pain and opioid consumption. Despite ease of administration, the effects of preoperative oral methadone are not well described in the literature. Aims: This pilot study investigated the effect of preoperative oral methadone on pain scores, analgesia requirements, and opioid-induced side effects. Methods: A randomized double-blind placebo-controlled model was used with sampling of patients undergoing sternotomy for isolated coronary artery bypass graft (CABG) surgery (ClinicalTrials.gov registration no. NCT02774499). Participants were randomized to receive oral methadone (0.3 mg/kg) or oral placebo prior to entering the operating room. The primary outcome was pain scores on a 0-10 Verbal Rating Scale. Secondary outcomes included morphine requirements using patient-controlled analgesia (PCA), time to extubation, level of sedation, and side effects such as nausea, vomiting, pruritus, hypoventilation, and hypoxia over a 72-h monitoring time. Results: Twenty-one patients completed the study. Oral methadone did not reduce pain scores in the methadone group (P = 0.08). However, postoperative morphine requirement during the first 24 h was reduced by a mean of 23 mg in the methadone group (mean difference, -23; 99% confidence interval [CI], 37-13 mg; P < 0.005). No reduction in pain scores or PCA morphine was observed beyond 24 h postoperatively. There was no difference in incidence of opioid-related side effects between groups throughout the postoperative period. Conclusions: Though preoperative oral methadone did not reduce pain scores, morphine requirements were reduced in the first 24 h post-CABG.

Subcutaneous ketamine for postoperative pain relief in Rwanda: a randomized clinical trial.

PURPOSE: Postoperative pain control is often inadequate in low-income countries such as Rwanda, prompting the search for an inexpensive improvement. A randomized controlled trial was conducted to study the use of subcutaneous ketamine for the management of postoperative pain in patients undergoing major surgery in Kigali, Rwanda. METHODS: Fifty-nine patients undergoing major abdominal, head and neck, plastic, or gynecological surgeries were studied. In addition to standard care, patients received five subcutaneous injections of ketamine 1 mg·kg-1 (ketamine group, n = 30) or normal saline (placebo group, n = 29) during the postoperative period. The first injection was administered in the postanesthesia care unit and then every 12 hr thereafter starting at 20:00 on the day of surgery. Pain was assessed three times per day using an 11-point verbal response scale. Patients were also assessed for side effects, including nausea and vomiting, hallucinations, nightmares, sedation, hypertension, and seizures. RESULTS: The mean (SD) overall postoperative pain scale score was higher in the control group than in the ketamine group [4.8 (1.7) vs 3.7 (1.5), respectively; difference of means, 1.1; 95% confidence interval [CI], 0.3 to 1.9; P = 0.009]. Brief hallucinations (ketamine group, 11 patients; placebo group, 0 patients; risk difference, 0.37; 95% CI, 0.18 to 0.54; P < 0.001) were associated with ketamine administration. CONCLUSIONS: Results of this study in Kigali, Rwanda showed that subcutaneous administration of ketamine 1 mg·kg-1 twice daily, in addition to standard postoperative care, produced a small improvement in postoperative pain but resulted in more minor side effects TRIAL REGISTRATION: www.clinicaltrials.gov (NCT02514122). Registered 31 July 2015.

Low-dose subcutaneous ketamine for postoperative pain management in Rwanda: a dose-finding study.

PURPOSE: Good pain control is not a normal part of surgical care in sub-Saharan Africa due to lack of resources. The primary objective of this study was to determine an efficacious dose of subcutaneous ketamine for postoperative pain for use in a future randomized controlled trial. METHODS: Following research ethics board and local hospital approval for this research, we obtained informed consent from 31 patients undergoing major surgery for a random walk dose-finding study. In addition to standard postoperative care, participants received five doses of subcutaneous ketamine at scheduled intervals from arrival in the postanesthesia care unit (PACU) to postoperative day 2. Participants received 50 mg of ketamine (minimum 0.6 to maximum 1.1 mg·kg-1, based on different body weights) for the first and second dose, with subsequent doses adjusted by 10 mg according to pain and side effects. Pain scores were recorded at rest and with movement. RESULTS: The following mean (standard deviation [SD]) pain scores at rest and with movement were recorded on arrival in the PACU and on the afternoon of postoperative days 1 and 2: [at rest: 8.2 (1.5), 3.2 (1.8), and 0.7 (1.0), respectively; with movement: 9.4 (0.8), 5.1 (1.7), and 2.4 (1.1), respectively]. This rate of improvement suggests possible pain relief through use of ketamine. The mean (SD) ketamine dose that appeared efficacious in pain reduction was 0.90 (0.23) mg·kg-1. There were no serious side effects. CONCLUSION: Adding subcutaneous ketamine to standard analgesic measures resulted in decreases in postoperative pain scores without serious side effects. These data can be used to inform a randomized controlled trial to compare subcutaneous ketamine plus standard care with placebo plus standard care for reducing postoperative pain.

Dexmedetomidine during total knee arthroplasty performed under spinal anesthesia decreases opioid use: a randomized-controlled trial.

BACKGROUND: It remains unclear whether the opioid-sparing effects of dexmedetomidine seen in patients undergoing general anesthesia are reproducible in patients undergoing spinal anesthesia. We hypothesized that the administration of intravenous dexmedetomidine for sedation during total knee arthroplasty under spinal anesthesia would decrease postoperative morphine consumption in the first 24 hr following surgery. METHODS: We conducted this prospective double-blind randomized-controlled trial in 40 patients (American Society of Anesthesiologists physical status I-III) undergoing total knee arthroplasty with a standardized spinal anesthetic. Patients were randomized to receive either a dexmedetomidine loading dose of 0.5 µg·kg(-1) over ten minutes, followed by an infusion of 0.5 µg·kg·hr(-1) for the duration of the surgery, or a normal saline loading dose and an infusion of an equivalent volume. The primary outcome was the consumption of morphine delivered via patient-controlled analgesia in the first 24 hr following surgery. RESULTS: The mean (SD) cumulative morphine at 24 hr in the dexmedetomidine group was 29.2 (11.2) mg compared with 61.2 (17.2) mg in the placebo group (mean difference, 32.0 mg; 95% confidence interval, 22.7 to 41.2; P < 0.001). In the dexmedetomidine group, there was a delay in the time to first analgesic request (P = 0.003) and a reduction in the mean morphine use at six and 12 hr following surgery (both P < 0.001). CONCLUSIONS: Dexmedetomidine was associated with a significant decrease in morphine use in the first 24 hr following total knee arthroplasty. Our study shows that an intraoperative infusion of dexmedetomidine for sedation in patients receiving spinal anesthesia can produce postoperative analgesic effects. This offers another potential adjunct in the multimodal pain management of these patients. This trial was registered at ClinicalTrials.gov (identifier NCT02026141).