Relationship between preinduction electroencephalogram patterns and propofol sensitivity in adult patients.

PURPOSE: To determine the precise induction dose, an objective assessment of individual propofol sensitivity is necessary. This study aimed to investigate whether preinduction electroencephalogram (EEG) data are useful in determining the optimal propofol dose for the induction of general anesthesia in healthy adult patients. METHODS: Seventy healthy adult patients underwent total intravenous anesthesia (TIVA), and the effect-site target concentration of propofol was observed to measure each individual's propofol requirements for loss of responsiveness. We analyzed preinduction EEG data to assess its relationship with propofol requirements and conducted multiple regression analyses considering various patient-related factors. RESULTS: Patients with higher relative delta power (ρ = 0.47, p < 0.01) and higher absolute delta power (ρ = 0.34, p = 0.01) required a greater amount of propofol for anesthesia induction. In contrast, patients with higher relative beta power (ρ = -0.33, p < 0.01) required less propofol to achieve unresponsiveness. Multiple regression analysis revealed an independent association between relative delta power and propofol requirements. CONCLUSION: Preinduction EEG, particularly relative delta power, is associated with propofol requirements during the induction of general anesthesia. The utilization of preinduction EEG data may improve the precision of induction dose selection for individuals.

Relationships between common carotid artery blood flow and anesthesia, pneumoperitoneum, and head-down tilt position: a linear mixed-effect analysis.

This study investigated the effects of pneumoperitoneum and the head-down tilt position on common carotid artery (CCA) blood flow in surgical patients. METHODS: This prospective observational study included 20 patients who underwent gynecological surgery. CCA blood flow was measured using Doppler ultrasound at four-time points: awake in the supine position [T1], 3 min after anesthesia induction in the supine position [T2], 3 min after pneumoperitoneum in the supine position [T3], and 3 min after pneumoperitoneum in the head-down tilt position [T4]. Hemodynamic and respiratory parameters were also recorded at each time point. Linear mixed-effect analyses were performed to compare CCA blood flow across the time points and assess its relationship with hemodynamic parameters. RESULTS: Compared with T1, CCA blood flow decreased significantly at T2 (345.4 [288.0-392.9] vs. 293.1 [253.0-342.6], P = 0.048). CCA blood flow were also significantly lower at T3 and T4 compared with T1 (345.4 [288.0-392.9] vs. 283.6 [258.8-307.6] and 287.1 [242.1-321.4], P = 0.005 and 0.016, respectively). CCA blood flow at T3 and T4 did not significantly differ from that at T2. Changes in CCA blood flow were significantly associated with changes in cardiac index and stroke volume index (P = 0.011 and 0.024, respectively). CONCLUSION: CCA blood flow was significantly decreased by anesthesia induction. Inducing pneumoperitoneum, with or without the head-down tilt position, did not further decrease CCA blood flow if the cardiac index remained unchanged. The cardiac index and stroke volume index were significantly associated with CCA blood flow. CLINICAL TRIAL REGISTRATION: Clinicaltrials.gov (NCT04233177, January 18, 2020).

Effect of remifentanil on post-operative analgesic consumption in patients undergoing shoulder arthroplasty after interscalene brachial plexus block: a randomized controlled trial.

PURPOSE: Remifentanil is useful in balanced anesthesia; however, there is concern regarding opioid-induced hyperalgesia. The effect of remifentanil on rebound pain, characterized by hyperalgesia after peripheral nerve block has rarely been studied. This study evaluated whether intraoperative remifentanil infusion may increase postoperative analgesic requirement in patients receiving preoperative interscalene brachial plexus block (IBP). METHODS: Sixty-eight patients undergoing arthroscopic shoulder surgery under general anesthesia were randomly allocated to remifentanil (R) or control (C) group. Preoperative IBP with 0.5% ropivacaine 15 mL was performed in all patients. Intraoperative remifentanil was administered only in the R group. Postoperative pain was controlled using intravenous patient-controlled analgesia (IV-PCA) and rescue analgesics. The primary outcome was the dosage of fentanyl-nefopam IV-PCA infused over 24 h postoperatively. The secondary outcomes included the numeric rating scale (NRS) score recorded at 4-h intervals over 24 h, amount of rescue analgesics and total postoperative analgesics used over 24 h, occurrence of intraoperative hypotension, postoperative nausea and vomiting (PONV) and delirium. RESULTS: The dosage of fentanyl-nefopam IV-PCA was significantly less in C group than R group for postoperative 24 h. Fentanyl 101 [63-158] (median [interquartile range]) µg was used in the C group, while fentanyl 161 [103-285] µg was used in the R group (median difference 64 µg, 95% CI 10-121 µg, P = 0.02). Nefopam 8.1 [5.0-12.6] mg was used in the C group, while nefopam 12.9 [8.2-22.8] mg was used in the R group (median difference 5.1 mg, 95% CI 0.8-9.7 mg, P = 0.02). The total analgesic consumption: the sum of PCA consumption and administered rescue analgesic dose, converted to morphine milligram equivalents, was higher in the R group than C group (median difference 10.9 mg, 95% CI 3.0-19.0 mg, P = 0.01). The average NRS score, the incidence of PONV and delirium, were similar in both groups. The incidence of intraoperative hypotension was higher in R group than C group (47.1% vs. 20.6%, P = 0.005). CONCLUSIONS: Remifentanil administration during arthroscopic shoulder surgery in patients undergoing preoperative IBP increased postoperative analgesic consumption.

Optimal angle of needle insertion for spinal anesthesia in patients with spondylolisthesis: an ultrasonographic study.

BACKGROUND: Spondylolisthesis is a common degenerative spinal deformity. At the level of spondylolisthesis, the anatomy of the interlaminar space may differ from normal spine, in which case optimal angle of the needle insertion for spinal anesthesia may change. This study compared the optimal angle of needle insertion during spinal anesthesia in patients with and without lumbar spondylolisthesis using ultrasound. METHODS: We recruited 40 patients, 20 with and 20 without lumbar spondylolisthesis (group S and N, respectively). Ultrasonography was performed in the transverse midline and parasagittal oblique views at the spondylolisthesis level and the adjacent upper level. We measured the probe application angle with the longest interlaminar height of the ligamentum flavum-dura mater complex (LFD), depth from the skin to the LFD, depth from the skin to the anterior complex, and intrathecal space width. A positive angle represented a cephalad angulation. RESULTS: The optimal needle insertion angle in the transverse midline view at the spondylolisthesis level was (-) 2.7 ± 3.4° in group S and 0.8 ± 2.5° in group N (P [Formula: see text] 0.001). In the parasagittal oblique view, it was (-) 2.7 ± 4.5° in group S and 1.0 ± 3.2° in group N (P = 0.004). There were no between-group differences in the angles at the upper level, with all cephalad angles in both views. Other ultrasound image data were comparable between groups. CONCLUSION: In patients with spondylolisthesis, caudad angulation of the spinal needle can aid successful spinal puncture at spondylolisthesis level, both in the midline and paramedian approaches. TRIAL REGISTRATION: www.ClinicalTrials.gov ( NCT04426916 ); registered 11 June 2020.

Ultrasound-guided versus conventional lung recruitment manoeuvres in laparoscopic gynaecological surgery: A randomised controlled trial.

BACKGROUND: Pneumoperitoneum and steep Trendelenburg position promote the formation of pulmonary atelectasis during laparoscopic gynaecological surgery. OBJECTIVE: To determine whether lung ultrasound-guided alveolar recruitment manoeuvres could reduce peri-operative atelectasis compared with conventional recruitment manoeuvres during laparoscopic gynaecological surgery. DESIGN: Randomised controlled trial. SETTING: Tertiary hospital, Republic of Korea, from August 2018 to January 2019. PATIENTS: Adult patients scheduled for laparoscopic gynaecological surgery under general anaesthesia. INTERVENTION: Forty patients were randomised to receive either ultrasound-guided recruitment manoeuvres (manual inflation until no visibly collapsed area was seen with lung ultrasonography; intervention group) or conventional recruitment manoeuvres (single manual inflation with 30 cmH2O pressure; control group). Recruitment manoeuvres were performed 5 min after induction and at the end of surgery in both groups. All patients received volume-controlled ventilation with a tidal volume of 8 ml kg-1 and a positive end-expiratory pressure of 5 cmH2O. MAIN OUTCOME MEASURES: The primary outcome was the lung ultrasound score at the end of surgery; a higher score indicates worse lung aeration. RESULTS: Lung ultrasound scores at the end of surgery were significantly lower in the intervention group compared with control group (median [IQR], 7.5 [6.5 to 8.5] versus 9.5 [8.5 to 13.5]; difference, -2 [95% CI, -4.5 to -1]; P = 0.008). The intergroup difference persisted in the postanaesthesia care unit (7 [5 to 8.8] versus 10 [7.3 to 12.8]; difference, -3 [95% CI, -5.5 to -1.5]; P = 0.005). The incidence of atelectasis was lower in the intervention group compared with control group at the end of surgery (35 versus 80%; P = 0.010) but was comparable in the postanaesthesia care unit (40 versus 55%; P = 0.527). CONCLUSIONS: The use of ultrasound-guided recruitment manoeuvres improves peri-operative lung aeration; these effects may persist in the postanaesthesia care unit. However, the long-term effects of ultrasound-guided recruitment manoeuvres on clinical outcomes should be the subject of future trials. TRIAL REGISTRATION: ClinicalTrials.gov (NCT03607240).

Efficacy of intra-operative administration of iron isomaltoside for preventing postoperative anaemia after total knee arthroplasty: A randomised controlled trial.

BACKGROUND: Postoperative anaemia is common after total knee arthroplasty (TKA). Emerging evidence shows the beneficial effects of peri-operative iron supplementation in patients at risk of postoperative anaemia. OBJECTIVE: To evaluate the efficacy of intra-operative administration of iron isomaltoside for the prevention of postoperative anaemia in patients undergoing TKA. DESIGN: Randomised, controlled, double-blind, parallel-group study. SETTING: A tertiary care teaching hospital; between 29 March 2018 and 16 April 2019. PATIENTS: Eighty-nine patients scheduled for unilateral TKA were included. INTERVENTION: Iron isomaltoside or placebo were administered intravenously over 30 min during surgical wound closure. MAIN OUTCOME MEASURES: The primary outcome measure was the incidence of anaemia at 30 days after TKA: anaemia was defined as haemoglobin less than 12 g dl-1 for female and less than 13 g dl-1 for male. RESULTS: In total, 89 patients were included in the final analysis (44 in the treatment group; 45 in the control group). The administered dose of iron isomaltoside in the treatment group was 1136 ±â€Š225 mg. The incidence of anaemia at 30 days after TKA was significantly lower in the treatment group (34.1%, 15/44) than that in the control group (62.2%, 28/45): relative risk 0.55 (95% confidence interval, 0.34 to 0.88), P = 0.008. Haemoglobin concentration, serum ferritin concentrations, and transferrin saturation were also significantly higher in the treatment group at 30 days after TKA. CONCLUSION: The intra-operative administration of iron isomaltoside effectively prevents postoperative anaemia in patients undergoing TKA, and thus it can be included in patient blood management protocols for reducing postoperative anaemia in these population. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT03470649.

Ultrasound-Assisted Versus Landmark-Guided Spinal Anesthesia in Patients With Abnormal Spinal Anatomy: A Randomized Controlled Trial.

BACKGROUND: Spinal anesthesia using a surface landmark-guided technique can be challenging in patients with anatomical alterations of the lumbar spine; however, it is unclear whether using ultrasonography can decrease the technical difficulties in these populations. We assessed whether an ultrasound-assisted technique could reduce the number of needle passes required for block success compared with the landmark-guided technique in patients with abnormal spinal anatomy. METHODS: Forty-four patients with abnormal spinal anatomy including documented lumbar scoliosis and previous spinal surgery were randomized to receive either surface landmark-guided or preprocedural ultrasound-assisted spinal anesthesia. All spinal procedures were performed by 1 of 3 experienced anesthesiologists. The primary outcome was the number of needle passes required for successful dural puncture. Secondary outcomes included the success rate on the first pass, total procedure time, periprocedural pain scores, and the incidences of radicular pain, paresthesia, and bloody tap during the neuraxial procedure. Intergroup difference in the primary outcome was assessed for significance using Mann-Whitney U test. RESULTS: The median (interquartile range [IQR; range]) number of needle passes was significantly lower in the ultrasound group than in the landmark group (ultrasound 1.5 [1-3 {1-5}]; landmark 6 [2-9.3 {1-15}]; P < .001). First-pass success was achieved in 11 (50.0%) and 2 (9.1%) patients in the ultrasound and landmark groups, respectively (P = .007). The total procedure time, defined as the sum of the time for identifying landmarks and performing spinal anesthesia, did not differ significantly between the 2 groups (ultrasound 141 seconds [115-181 seconds {101-336 seconds}]; landmark 146 seconds [90-295 seconds {53-404 seconds}]; P = .888). The ultrasound group showed lower periprocedural pain scores compared with the landmark group (ultrasound 3.5 [1-5 {0-7}]; landmark 5.5 [3-8 {0-9}]; P = .012). The incidences of complications during the procedure showed no significant differences between the 2 groups. CONCLUSIONS: For anesthesiologists with experience in neuraxial ultrasonography, the use of ultrasound significantly reduces the technical difficulties of spinal anesthesia in patients with abnormal spinal anatomy compared with the landmark-guided technique. Our results can lead to practical suggestions that encourage the use of neuraxial ultrasonography for spinal anesthesia in such patients.

The cumulative duration of bispectral index less than 40 concurrent with hypotension is associated with 90-day postoperative mortality: a retrospective study.

BACKGROUND: The relationship between intraoperative low bispectral index (BIS) values and poor clinical outcomes has been controversial. Intraoperative hypotension is associated with postoperative complication. The purpose of this study was to investigate the influence of intraoperative low BIS values and hypotension on postoperative mortality in patients undergoing major abdominal surgery. METHODS: This retrospective study analyzed 1862 cases of general anesthesia. We collected the cumulative time of BIS values below 20 and 40 as well as electroencephalographic suppression and documented the incidences in which these states were maintained for at least 5 min. Durations of intraoperative mean arterial pressures (MAP) less than 50 mmHg were also recorded. Multivariable logistic regression was used to evaluate the association between suspected risk factors and postoperative mortality. RESULTS: Ninety-day mortality and 180-day mortality were 1.5 and 3.2% respectively. The cumulative time in minutes for BIS values falling below 40 coupled with MAP falling below 50 mmHg was associated with 90-day mortality (odds ratio, 1.26; 95% confidence interval, 1.04-1.53; P = .019). We found no association between BIS related values and 180-day mortality. CONCLUSIONS: The cumulative duration of BIS values less than 40 concurrent with MAP less than 50 mmHg was associated with 90-day postoperative mortality, not 180-day postoperative mortality.

Neutrophil/Lymphocyte Ratio in Patients Undergoing Noncardiac Surgery After Coronary Stent Implantation.

OBJECTIVE: Perioperative cell count-associated predictors, including the neutrophil/lymphocyte ratio (N/LR) and platelet/lymphocyte ratio (P/LR), are associated with poor clinical outcomes including myocardial injury. Study investigators aimed to examine the association among the perioperative N/LR, P/LR, and postoperative major adverse cardiovascular and cerebral events (MACCE) after noncardiac surgery in patients with drug-eluting stent (DES) insertion. DESIGN: Retrospective and observational. SETTING: Single university hospital. PARTICIPANTS: The study comprised 965 patients who underwent noncardiac surgery within 6 months after DES implantation. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Baseline perioperative clinical parameters, including N/LR and P/LR measured before surgery, immediately after surgery, and on postoperative day (POD) 1, were obtained. MACCE was defined as a composite of nonfatal myocardial infarction, coronary revascularization, nonhemorrhagic stroke, and pulmonary embolism within 1 month after surgery. Multivariate logistic regression analysis and propensity score matching were used to identify predictors of MACCE after surgery. MACCE occurred in 67 patients (6.9%) and was more common in patients with N/LR on POD 1 >4.3 (multivariable-adjusted odds ratio [OR] 2.03, 95% confidence interval [CI] 1.12-2.79; p = 0.040 and as a continuous N/LR [OR 1.17, 95% CI 1.08-1.27; p < 0.001]). This association was consistent after propensity score matching and was stronger when the antiplatelet agent was stopped before surgery (OR 3.02, 95% CI 2.14-4.48; p = 0.006 for stopping dual antiplatelet therapy). CONCLUSIONS: In patients undergoing noncardiac surgery within 6 months after DES implantation, elevated N/LR on POD 1 is independently associated with postoperative MACCE. Elevated postoperative N/LR as a marker of systemic inflammation may help to predict the development of MACCE in these high-risk patients.

Total Intravenous Anesthesia versus Inhalation Anesthesia for Breast Cancer Surgery: A Retrospective Cohort Study.

BACKGROUND: The association between type of anesthesia used and recurrence of cancer remains controversial. This retrospective cohort study compared the influence of total IV anesthesia and inhalation anesthesia on the primary outcome of recurrence-free survival after breast cancer surgery. METHODS: The authors reviewed the electronic medical records of patients who had breast cancer surgery at a tertiary care teaching hospital between January 2005 and December 2013. The patients were grouped according to whether IV or inhalation anesthesia was used for surgery. Propensity score matching was used to account for differences in baseline characteristics. Kaplan-Meier survival curves were constructed to evaluate the influence of type of anesthesia on recurrence-free survival and overall survival. The risks of cancer recurrence and all-cause mortality were compared between each type of anesthesia. RESULTS: Of 7,678 patients who had breast cancer surgery during the study period, data for 5,331 patients were available for analysis (IV group, n = 3,085; inhalation group, n = 2,246). After propensity score matching, 1,766 patients remained in each group. Kaplan-Meier survival curves showed that there was no significant difference in recurrence-free survival or overall survival between the two groups, with 5-yr recurrence-free survival rates of 93.2% (95% CI, 91.9 to 94.5) in the IV group and 93.8% (95% CI, 92.6 to 95.1) in the inhalation group. Inhalation anesthesia had no significant impact on recurrence-free survival (hazard ratio, 0.96; 95% CI, 0.69 to 1.32; P = 0.782) or overall survival (hazard ratio, 0.96; 95% CI, 0.69 to 1.33, P = 0.805) when compared with total IV anesthesia. CONCLUSIONS: The authors found no association between type of anesthesia used and the long-term prognosis of breast cancer. The results of this retrospective cohort study do not suggest specific selection of IV or inhalation anesthesia for breast cancer surgery.

Safety margin for needle placement during lumbar plexus block: An anatomical study using magnetic resonance imaging.

PURPOSE: We aimed to provide anatomic characteristics of the lumbar plexus and a safety margin for needle placement during lumbar plexus block in adults. METHODS: Lumbar spine magnetic resonance images from 377 adults were reviewed. We determined the depth of the lumbar plexus from the needle insertion point for the modified traditional and Capdevila's approaches at the L4 and L5 levels. The relationship of age, height, and body weight with lumbar plexus depth, and the presence of the kidney on the transverse plane at the L4 level were assessed. RESULTS: The lumbar plexus was deeper at the L5 level than at the L4 level for both approaches (mean difference 3.2 mm [95% confidence interval (CI), 2.4 to 4.0] for the modified traditional approach; mean difference 4.4 mm [95% CI, 3.7 to 5.2] for Capdevila's approach). Eighty-six (22.8%) patients had an L4 transverse process shorter than 40 mm, which implies that the needle may not contact the L4 transverse process with the modified traditional approach. The mean (standard deviation) of safety margins for needle insertion, defined as the distance from the posterior aspect of the L4 transverse process to the anterior margin of the psoas muscle, were 45 (8) and 44 (6) mm, respectively for the modified traditional and Capdevila's approach (mean difference, 0.5 mm; 95% CI, -0.1 to 1.1]). The lumbar plexus depth for each approach at the L4 level was predicted using the following equations: Depth (mm) = 87.24 - 0.36 × height (cm) + 0.69 × weight (kg) for the modified traditional approach (r2 = 0.37) and Depth (mm) = 86.51 - 0.35 × height (cm) + 0.61 × weight (kg) for Capdevila's approach (r2 = 0.33). The kidney was observed at the L4 level in 60 (15.9%) patients, with higher incidence in patients over 70 yr and those shorter than 150 cm. CONCLUSION: The surface anatomic relations of the lumbar plexus found in this study may be useful for performing successful and safe lumbar plexus block.

RéSUMé: OBJECTIF: Nous avons cherché à fournir des données anatomiques du plexus lombaire et de la marge de sécurité pour le positionnement de l'aiguille au cours d'un bloc lombaire chez l'adulte. MéTHODES: Les images par résonance magnétique de la colonne vertébrale lombaire de 377 adultes ont été analysées. Nous avons déterminé la profondeur du plexus lombaire à partir du point d'insertion de l'aiguille pour les approches traditionnelle modifiée et de Capdevila aux niveaux L4 et L5. Les corrélations de l'âge, de la taille et du poids corporel avec la profondeur du plexus lombaire et la présence du rein sur le plan de l'apophyse transverse au niveau de L4 ont été évaluées. RéSULTATS: Le plexus lombaire était plus profond à l'étage L5 qu'à l'étage L4 pour les deux approches (différence moyenne : 3,2 mm [intervalle de confiance (IC) à 95 % : 2,4 à 4,0] pour l'approche traditionnelle modifiée; différence moyenne : 4,4 mm [IC à 95 % : 3,7 à 5,2] pour l'approche de Capdevila). Quatre-vingt-six patients (22,8 %) avaient l'apophyse transverse de L4 mesurant moins de 40 mm, ce qui implique que l'aiguille pourrait ne pas faire contact avec cette apophyse avec l'approche traditionnelle modifiée. Les marges de sécurité pour l'insertion de l'aiguille, définies comme étant la distance moyenne (écart-type) entre la face postérieure de l'apophyse transverse de L4 et la marge antérieure du muscle psoas, étaient de 45 (8) mm et 44 (6) mm pour, respectivement, l'approche traditionnelle modifiée et l'approche de Capdevila (différence des moyennes, 0,5 mm; IC à 95 % : −0,1 à 1,1). La profondeur du plexus lombaire pour chaque approche au niveau L4 a été prédite à l'aide des équations suivantes : Profondeur (mm) = 87,24 − 0,36 × taille (cm) + 0,69 × poids (kg) pour l'approche traditionnelle modifiée (r2 = 0,37) et Profondeur (mm) = 86,51 − 0,35 × taille (cm) + 0,61 × poids (kg) pour l'approche de Capdevila (r2 = 0,33). Le rein a été observé au niveau L4 chez 60 patients (15,9 %) avec une plus grande incidence chez les patients âgés de plus de 70 ans et chez ceux dont la taille était inférieure à 150 cm. CONCLUSION: Les rapports anatomiques de la surface du corps et du plexus lombaire identifiés dans cette étude peuvent contribuer à la réalisation d'un bloc lombaire efficace et sécuritaire.

The effect of neck extension on success rate of blind intubation through Ambu® AuraGain™ laryngeal mask: a randomized clinical trial.

PURPOSE: Although the use of fibreoptic guidance is recommended for tracheal intubation through supraglottic airway devices, it can also be performed in a blind manner. Based on the previous finding that a fibreoptic view of the vocal cords was better in the extended neck position than in the neutral position, we hypothesized that neck extension can better facilitate blind intubation through the Ambu® AuraGain™ laryngeal mask than the neutral position. METHODS: Patients undergoing general anesthesia were randomly assigned to the extension group or the neutral group. After induction of anesthesia, the AuraGain™ was placed in the oropharynx, followed by blind intubation through the AuraGain™ in the assigned neck position within a maximum of two attempts. The primary outcome was successful blind intubation through the AuraGain™ in the first attempt. RESULTS: Of 168 adult patients screened, 124 patients were enrolled and 121 patients were included in the final analysis (extension group, n = 59; neutral group, n = 62). The incidence of successful blind intubation on the first attempt was significantly higher in the extension group than in the neutral group (68% vs. 47%, respectively; relative risk [RR], 1.45; 95% confidence interval [CI], 1.05 to 1.99; P = 0.02). The overall incidence of successful blind intubation was also significantly higher in the extension group than in the neutral group (71% vs 50%, respectively; RR, 1.42; 95% CI, 1.06 to 1.92; P = 0.02). The time required for successful blind intubation and the incidence of hoarseness, cough, or sore throat at 24 hr after extubation did not differ between groups. CONCLUSION: Neck extension can be used to facilitate blind intubation through the Ambu® AuraGain™ laryngeal mask. Considering the relatively high failure rate, blind intubation via the AuraGain™ should be used as an alternative, not as a first-line choice. TRIAL REGISTRATION: www.ClinicalTrials.gov (NCT03408431); registered 24 January 2018.

Ultrasound-assisted vs. landmark-guided paramedian spinal anaesthesia in the elderly: A randomised controlled trial.

BACKGROUND: Neuraxial ultrasound might improve the efficacy of spinal anaesthesia but this has not been tested for the paramedian approach in the elderly. OBJECTIVE: The current study aims to assess whether the ultrasound-assisted paramedian technique can decrease the number of needle passes required for success compared with the landmark-guided paramedian technique in the elderly. DESIGN: Randomised controlled study. SETTING: Single-institution, tertiary-level hospital in Seoul, Republic of Korea from October 2017 to January 2018. PATIENTS: Eighty patients aged at least 60 years undergoing orthopaedic surgery. INTERVENTION: All received paramedian spinal anaesthesia by either the landmark-guided or preprocedural ultrasound-assisted technique. MAIN OUTCOME MEASURES: The number of needle passes required for successful dural puncture. RESULTS: The number of needle passes (median [interquartile range]) was significantly lower (1.0 [1.0 to 2.0] vs. 4.5 [2.0 to 7.0]) and the success rate at first pass significantly higher at 65.0 vs. 17.5% in the ultrasound compared with the landmark group (both P < 0.001). The ultrasound-assisted technique required a longer time for establishing landmarks (117.5 s [85.5 to 150.7 s] vs. 17.5 s [14.0 to 23.0 s]) and for total procedure (181.5 s [133.5 to 212.5 s] vs. 92.5 s [62.5 to 176.5 s]) but a shorter time for administering spinal anaesthesia (39.5 s [31.5 to 71.3 s] vs. 77.0 s [45.8 to 136.5 s]; all, P < 0.001) than the palpation-guided technique. The ultrasound group showed lower periprocedural pain scores (3 [2 to 4] vs. 4 [4 to 6]; P = 0.009) and discomfort scores (2 [0 to 3] vs. 5 [2 to 6]; P = 0.003) than the landmark group. CONCLUSION: Compared with the landmark-guided paramedian technique, the ultrasound-assisted paramedian technique decreases the number of needle manipulations and periprocedural pain and discomfort scores in the elderly. Our results suggest that neuraxial ultrasonography facilitates the performance of spinal anaesthesia in the elderly. TRIAL REGISTRATION: NCT03316352.

Comparative effectiveness of interventions for managing postoperative catheter-related bladder discomfort: a systematic review and network meta-analysis.

BACKGROUND: Although many drugs or interventions have been studied to manage catheter-related bladder discomfort (CRBD), their comparative effectiveness is unknown. We attempted to assess the comparative effectiveness of the strategies to manage CRBD in patients undergoing urologic surgery including amikacin, solifenacin, darifenacin, butylscopolamine, dexmedetomidine, gabapentin, glycopyrrolate, ketamine, oxybutynin, resiniferatoxin, tolterodine, tramadol, caudal block, dorsal penile nerve block, lidocaine-prilocaine cream. METHODS: We performed an arm-based network meta-analysis including 29 trials with 2841 participants. Goodness of model fit was evaluated by deviance information criteria (DIC). The incidence of CRBD at 0, 1, and 6 h after surgery and the incidence of moderate to severe CRBD at 0, 1, and 6 h after surgery were compared. RESULTS: Random effect model was selected according to DIC. Most of the drugs significantly decreased the incidence of CRBD except amikacin, tramadol at 0 and 1 h after surgery. Dexmedetomidine, solifenacin, caudal block, dorsal penile nerve block, resiniferatoxin, and gabapentin 1200 mg p.o. significantly decreased the incidence of CRBD at 6 h after surgery (gabapentin 1200: Odds ratio [OR] 0.02; SUCRA 95.6). Dexmedetomidine and tolterodine significantly decreased the incidence of moderate to severe CRBD at 0, 1, and 6 h after surgery (tolterodine at 6 h: OR 0.05; SUCRA 73.7). CONCLUSIONS: Gabapentin was ranked best regarding the overall incidence of CRBD, while tolterodine was ranked best in reducing the severity of CRBD. However, a firm conclusion cannot be made from our analysis due to small-study number and heterogeneity regarding study setting and outcome measurement.

Deep vs. moderate neuromuscular blockade during laparoscopic surgery: A systematic review and meta-analysis.

BACKGROUND: Previous studies have reported that deep neuromuscular block (posttetanic-count 1 to 2 twitches) improves surgical conditions during laparoscopy compared with moderate block (train-of-four count: 1 to 2 twitches). However, comparisons of surgical conditions were made using different scales and assessment intervals with variable results. OBJECTIVE: To explore the heterogeneity of previous comparisons between deep and moderate neuromuscular block. DESIGN: Systematic review and meta-analysis of randomised controlled trials (RCTs). DATA SOURCES: Medline, EMBASE and Cochrane Central Register of Controlled Trials were searched from inception to October 2017. ELIGIBILITY CRITERIA: Our meta-analysis included RCTs comparing the effects of deep with moderate neuromuscular block on surgical field conditions during laparoscopic surgery. The frequency of excellent or good operating conditions on a surgical rating scale was compared. Heterogeneity was assessed by subgroup analyses. RESULTS: Eleven RCTs involving 844 patients were included. On the surgical rating scale, the frequency of excellent or good operating conditions was higher with deep block compared with a moderate block (odds ratio 2.83, 95% confidence interval 1.34 to 5.99, P = 0.007, I = 59%). We analysed surgical rating according to the number of assessments made. There was a significant difference in surgical rating with multiple assessments, but no difference when the assessment was made on only one occasion. A significant difference in rating was noted with variable abdominal pressures; there was no significant difference with the same fixed abdominal pressure. Trial sequential analysis demonstrated that the cumulative z-curve crossed the O'Brien-Fleming significance boundary. However, required information size was not achieved. CONCLUSION: Deep block was associated with excellent or good surgical rating more frequently than moderate block. However, this finding was not consistent on subgroup analyses based on frequencies of assessment of surgical conditions and abdominal pressure. Further studies are required to address the heterogeneity and power shortage demonstrated by the trial sequential analysis.

Positive end-expiratory pressure-induced increase in external jugular venous pressure does not predict fluid responsiveness in laparoscopic prostatectomy.

BACKGROUND: Dynamic change in central venous pressure (CVP) was associated with fluid responsiveness. External jugular venous pressure (EJVP) may reliably estimate CVP and have the advantages of being less invasive. We investigated whether increase in EJVP induced by positive end-expiratory pressure (PEEP) could be a reliable predictor of fluid responsiveness in patients undergoing robot-assisted laparoscopic prostatectomy (RALP). METHODS: Fifty patients who underwent RALP with steep Trendelenburg position were enrolled. PEEP of 10 cmH2O was applied for 5 min and then 300 ml of colloid was administered. EJVP, stroke volume variation (SVV), and cardiac index calculated by pulse contour method were measured before and after the PEEP challenge and colloid administration. Increase in cardiac index > 10% was used to define the fluid responsiveness. RESULTS: Twenty-six patients were fluid responders. Neither the increase in EJVP after the initial PEEP nor SVV was significantly different between responders and non-responders. They were not significantly correlated with an increase in cardiac index. The areas under the receiver operating characteristic curve (AUC) of these two variables were not significantly greater than 0.5. However, a post hoc analysis revealed that AUC of a decrease in EJVP after removal of PEEP was significantly greater than 0.50. CONCLUSION: Our study results suggested that SVV and increase in EJVP after applying PEEP were not accurate predictors of fluid responsiveness during RALP. Further studies are required to find an adequate preload index in robot-assisted urologic surgery with steep Trendelenburg position.

Comparison of Supraclavicular and Infraclavicular Brachial Plexus Block: A Systemic Review of Randomized Controlled Trials.

BACKGROUND: Supraclavicular (SC) and infraclavicular (IC) brachial plexus block (BPB) are commonly used for upper extremity surgery. Recent clinical studies have compared the effect of SC- and IC-BPB, but there have been controversies over spread of sensory blockade in each of the 4 peripheral nerve branches of brachial plexus. METHODS: This study included a systemic review, using the Medline and EMBASE database from their inceptions through March 2016. Randomized controlled trials (RCTs) comparing SC- and IC-BPB were included. The prespecified primary outcome was the incidences of incomplete sensory blockade in each of the 4 terminal nerve branches of brachial plexus. Secondary outcome included the incidence of successful blockade, performance time, onset of sensory block, duration of analgesia, and complication rates. RESULTS: Ten RCTs involving 676 patients were included. Pooled analyses showed the incidence of incomplete block at 30 minutes in radial nerve territory was significantly higher in IC-BPB, favoring SC-BPB (risk ratio 0.39; 95% confidence interval [0.17-0.88], P = .02, I = 0%). However, subgroup analysis according to the number of injections of IC-BPB showed that double or triple injections IC-BPB yielded no difference in the incomplete radial block. Furthermore, the incidence of incomplete ulnar block at 30 minutes was significantly lower in IC-BPB when using double or triple injection IC-BPB. There was no difference in the secondary outcomes between SC- and IC-BPB groups, with the exception of complication rates. The incidence of paresthesia/pain on local anesthetic injection, phrenic nerve palsy, and Horner syndrome was significantly higher in the SC group, favoring IC-BPB. CONCLUSIONS: This meta-analysis demonstrated that IC-BPB showed a significantly high incidence of incomplete radial nerve sensory block at 30 minutes, which may be avoided by double or triple injection. Furthermore, IC-BPB with multiple injection technique showed significantly lower incidence of incomplete ulnar block than SC-BPB. There were no differences in the incidence of successful blockade, block onset, and duration of analgesia between SC- and IC-BPB. Procedure-related paresthesia/pain and adjacent nerve-related complications were more frequent in SC-BPB. However, because of the small sample size, publication bias remains a concern when interpreting our results. Further studies with sufficient sample size and reporting large number of outcomes are required.

Comparative efficacy and safety of anticoagulants for prevention of venous thromboembolism after hip and knee arthroplasty.

Background and purpose - New oral anticoagulants have been developed to prevent venous thromboembolism (VTE) after knee or hip arthroplasty. Although there have been several network meta-analyses (NMA) to compare different regimens, an NMA including 2 different enoxaparin doses and edoxaban has not been performed. Methods - Standard NMA for fondaparinux, dabigatran, rivaroxaban, apixaban, edoxaban, and enoxaparin was performed. Outcome variables included a composite of total VTE and major/clinically relevant bleeding. The rank probabilities of each treatment outcome were summarized by the surface under the cumulative ranking curve. Results - Fondaparinux, rivaroxaban, and apixaban were associated with a reduced risk of VTE compared with enoxaparin, while dabigatran was not. None of these 3 drugs increased bleeding compared with enoxaparin 30 mg twice daily. However, fondaparinux and rivaroxaban increased bleeding compared with enoxaparin 40 mg once daily, while apixaban did not. Apixaban was even associated with decreased major/clinically relevant bleeding compared with enoxaparin 30 mg twice daily or 40 mg once daily. When edoxaban was included in the NMA, edoxaban decreased VTE and did not increase bleeding compared with enoxaparin. Interpretation - A higher efficacy of fondaparinux and rivaroxaban compared with enoxaparin was associated with increased bleeding tendency, while apixaban was superior to enoxaparin regarding both efficacy and safety. A clustered ranking plot showed that apixaban might be the most preferred regarding efficacy and safety. However, our results were driven by indirect statistical inference and were limited by the heterogeneity of the bleeding outcome definitions, drug initiation and continuation, and different surgery types.

Predictive Value of Intraoperative Thromboelastometry for the Risk of Perioperative Excessive Blood Loss in Infants and Children Undergoing Congenital Cardiac Surgery: A Retrospective Analysis.

OBJECTIVE: Laboratory hemostatic variables and parameters of rotational thromboelastometry (ROTEM) were evaluated for their ability to predict perioperative excessive blood loss (PEBL) after congenital cardiac surgery. DESIGN: Retrospective and observational. SETTING: Single, large university hospital. PARTICIPANTS: The study comprised 119 children younger than 10 years old undergoing congenital cardiac surgery with cardiopulmonary bypass (CPB). MEASUREMENTS AND MAIN RESULTS: Intraoperative excessive blood loss was defined as estimated blood loss≥50% of estimated blood volume (EBV). Postoperative excessive blood loss was defined as measured postoperative chest tube and Jackson-Pratt drainage≥30% of EBV over 12 hours or≥50% of EBV over 24 hours in the intensive care unit. PEBL was defined as either intraoperative or postoperative excessive blood loss. External temogram (EXTEM) and fibrinogen temogram (FIBTEM) were analyzed before and after CPB with ROTEM and laboratory hemostatic variables. Multivariate logistic regression was performed. Incidence of PEBL was 19.3% (n = 23). Independent risk factors for PEBL were CPB time>120 minutes, post-CPB FIBTEM alpha-angle, clot firmness after 10 minutes<5 mm, post-CPB EXTEM alpha-angle, clot firmness after 10 minutes<30 mm, and post-CPB EXTEM maximal lysis>20%. Laboratory hemostatic variables were not significant in multivariate analysis. The risk prediction model was developed from the results of multivariate analysis. The area under the receiver operating characteristic curve was 0.94 (95% confidence interval: 0.90-0.99). CONCLUSIONS: Post-CPB ROTEM may be useful for predicting both intraoperative and postoperative excessive blood loss in congenital cardiac surgery. This study provided an accurate prediction model for PEBL and supported intraoperative transfusion guidance using post-CPB FIBTEM-A10 and EXTEM-A10.