La Biblio du Mois : Octobre 2015
Ce mois-ci, l’article publié par l’AJAR sur l’activité de remplacement dans la spécialité mais également des études majeures notamment sur l’hypothermie thérapeutique dans le traumatisme crânien relançant le débat sur la fin (ou non) de l’hypothermie thérapeutique…
Hypothermie thérapeutique dans le traumatisme crânien
In patients with traumatic brain injury, hypothermia can reduce intracranial hypertension. The benefit of hypothermia on functional outcome is unclear.
We randomly assigned adults with an intracranial pressure of more than 20 mm Hg despite stage 1 treatments (including mechanical ventilation and sedation management) to standard care (control group) or hypothermia (32 to 35°C) plus standard care. In the control group, stage 2 treatments (e.g., osmotherapy) were added as needed to control intracranial pressure. In the hypothermia group, stage 2 treatments were added only if hypothermia failed to control intracranial pressure. In both groups, stage 3 treatments (barbiturates and decompressive craniectomy) were used if all stage 2 treatments failed to control intracranial pressure. The primary outcome was the score on the Extended Glasgow Outcome Scale (GOS-E; range, 1 to 8, with lower scores indicating a worse functional outcome) at 6 months. The treatment effect was estimated with ordinal logistic regression adjusted for prespecified prognostic factors and expressed as a common odds ratio (with an odds ratio <1.0 favoring hypothermia).
We enrolled 387 patients at 47 centers in 18 countries from November 2009 through October 2014, at which time recruitment was suspended owing to safety concerns. Stage 3 treatments were required to control intracranial pressure in 54% of the patients in the control group and in 44% of the patients in the hypothermia group. The adjusted common odds ratio for the GOS-E score was 1.53 (95% confidence interval, 1.02 to 2.30; P=0.04), indicating a worse outcome in the hypothermia group than in the control group. A favorable outcome (GOS-E score of 5 to 8, indicating moderate disability or good recovery) occurred in 26% of the patients in the hypothermia group and in 37% of the patients in the control group (P=0.03).
In patients with an intracranial pressure of more than 20 mm Hg after traumatic brain injury, therapeutic hypothermia plus standard care to reduce intracranial pressure did not result in outcomes better than those with standard care alone.
Solutés de remplissage et de perfusion de base
Revue sur la péricardite
Pratique de l’activité de remplacement en libéral chez les Anesthésistes-Réanimateurs
Effet du Sugammadex sur la curarisation partielle
Brueckmann, BJA, 2015 doi: 10.1093/bja/aev104
This study aimed to investigate whether reversal of rocuronium-induced neuromuscular blockade with sugammadex reduced the incidence of residual blockade and facilitated operating room discharge readiness.
Adult patients undergoing abdominal surgery received rocuronium, followed by randomized allocation to sugammadex (2 or 4 mg kg−1) or usual care (neostigmine/glycopyrrolate, dosing per usual care practice) for reversal of neuromuscular blockade. Timing of reversal agent administration was based on the providers’ clinical judgement. Primary endpoint was the presence of residual neuromuscular blockade at PACU admission, defined as a train-of-four (TOF) ratio <0.9, using TOF-Watch® SX. Key secondary endpoint was time between reversal agent administration and operating room discharge-readiness; analysed with analysis of covariance.
Of 154 patients randomized, 150 had a TOF value measured at PACU entry. Zero out of 74 sugammadex patients and 33 out of 76 (43.4%) usual care patients had TOF-Watch® SX-assessed residual neuromuscular blockade at PACU admission (odds ratio 0.0, 95% CI [0–0.06], P<0.0001). Of these 33 usual care patients, 2 also had clinical evidence of partial paralysis. Time between reversal agent administration and operating room discharge-readiness was shorter for sugammadex vs usual care (14.7 vs18.6 min respectively; P=0.02).
After abdominal surgery, sugammadex reversal eliminated residual neuromuscular blockade in the PACU, and shortened the time from start of study medication administration to the time the patient was ready for discharge from the operating room.
Labilité tensionnelle per-opératoire associée à une meilleure survie ?
Levin et al., BJA, 2015 doi: 10.1093/bja/aev293
Arterial blood pressure lability, defined as rapid changes in arterial blood pressure, occurs commonly during anaesthesia. It is believed that hypertensive patients exhibit more lability during surgery and that lability is associated with poorer outcomes. Neither association has been rigorously tested. We hypothesized that hypertensive patients have more blood pressure lability and that increased lability is associated with increased 30 day mortality.
This was a retrospective single-centre study of surgical patients from July 2008 to December 2012. Intraoperative data were extracted from the electronic anaesthesia record. Lability was calculated as the modulus of the percentage change in mean arterial pressure between consecutive 5 min intervals. The number of episodes of lability >10% was tabulated. Multivariate logistic regression was performed to determine the association between lability and 30 day mortality using derivation and validation cohorts.
Inclusion criteria were met by 52 919 subjects. Of the derivation cohort, 53% of subjects were hypertensive and 42% used an antihypertensive medication. The median number of episodes of lability >10% was 9 (interquartile range 5–14) per patient. Hypertensive subjects demonstrated more lability than normotensive patients, 10 (5–15) compared with 8 (5–12), P<0.0001. In subjects taking no antihypertensive medication, lability >10% was associated with decreased 30 day mortality, odds ratio (OR) per episode 0.95 [95% confidence interval (CI) 0.92–0.97],P<0.0001. This result was confirmed in the validation cohort, OR 0.96 (95% CI 0.93–0.99), P=0.01, and in hypertensive patients taking no antihypertensive medication, OR 0.96 (95% CI 0.93–0.99), P=0.002. Use of any antihypertensive medication class reduced this effect.
Intraoperative arterial blood pressure lability occurs more often in hypertensive patients. Contrary to common belief, increased lability was associated with decreased 30 day mortality.
Immunoparalysie : l’implication du DAMPs dans l’ACR
Timmermans et al., CCM, 2015 doi: 10.1097/CCM.0000000000001204
After cardiac arrest, patients are highly vulnerable toward infections, possibly due to a suppressed state of the immune system called “immunoparalysis.” We investigated if immunoparalysis develops following cardiac arrest and whether the release of danger-associated molecular patterns could be involved.
ICU of a university medical center.
Fourteen post–cardiac arrest patients treated with mild therapeutic hypothermia for 24 hours and 11 control subjects.
MEASUREMENTS AND MAIN RESULTS
Plasma cytokines showed highest levels within 24 hours after cardiac arrest and decreased during the next 2 days. By contrast, ex vivo production of cytokines interleukin-6, tumor necrosis factor-α, and interleukin-10 by lipopolysaccharide-stimulated leukocytes was severely impaired compared with control subjects, with most profound effects observed at day 0, and only partially recovering afterward. Compared with incubation at 37°C, incubation at 32°C resulted in higher interleukin-6 and lower interleukin-10 production by lipopolysaccharide-stimulated leukocytes of control subjects, but not of patients. Plasma nuclear DNA, used as a marker for general danger-associated molecular pattern release, and the specific danger-associated molecular patterns (EN-RAGE and heat shock protein 70) were substantially higher in patients at days 0 and 1 compared with control subjects. Furthermore, plasma heat shock protein 70 levels were negatively correlated with ex vivo production of inflammatory mediators interleukin-6, tumor necrosis factor-α, and interleukin-10. Extracellular newly identified receptor for advanced glycation end products-binding protein levels only showed a significant negative correlation with ex vivo production of interleukin-6 and tumor necrosis factor-α and a borderline significant inverse correlation with interleukin-10. No significant correlations were observed between plasma nuclear DNA levels and ex vivo cytokine production.
Release of danger-associated molecular patterns during the first days after cardiac arrest is associated with the development of immunoparalysis. This could explain the increased susceptibility toward infections in cardiac arrest patients.
Utilisation de la dexmedetomidine dans la péridurale
Keplinger et al., EJA, 2015 doi: 10.1097/EJA.0000000000000246
Previous data have indicated the efficacy of dexmedetomidine as an additive to peripheral regional anaesthesia. There are no pharmacodynamic data regarding the addition of dexmedetomidine to local anaesthetics for perineural administration.
The objective of this study is to assess the dose-dependency of dexmedetomidine when injected with ropivacaine for peripheral nerve blockade.
A randomised, triple-blind, controlled study in volunteers.
Department of Clinical Pharmacology, Medical University of Vienna.
All volunteers received an ulnar nerve block with 22.5 mg ropivacaine alone (R), or mixed with 50 (RD50), 100 (RD100) or 150 μg (RD150) dexmedetomidine.
MAIN OUTCOME MEASURES
The primary outcome was the duration of complete sensory block to pinprick and time to complete recovery of pinprick. Secondary outcomes included block success and onset time, motor block, haemodynamic parameters and sedation level.
There was a significant dose-dependent (P < 0.0001) increase in the mean duration (SD) of sensory block with dexmedetomidine: R: 8.7 (1.5) h, RD50: 16.4 (4.0) h, RD100: 20.4 (2.8) h and group RD150: 21.2 (1.7) h. Sedation was also enhanced in a dose-dependent (P < 0.001) manner. Two volunteers each receiving 150 μg dexmedetomidine had postblock paraesthesia for 72 h.
Dexmedetomidine mixed with ropivacaine produces a dose-dependent prolongation of sensory block and clinically relevant dose-dependent sedation. Dexmedetomidine 100 μg may represent a balance between efficacy and sedation.
ALR : Bloc des carrés lombaires dans la césarienne
Blanco, et al., EJA, 2015 doi: 10.1097/EJA.0000000000000299
Effective postoperative analgesia after caesarean section is important because it enables early ambulation and facilitates breast-feeding. Several case reports have shown that local anaesthetic injection around the quadratus lumborum muscle is effective in providing pain relief after various abdominal operations and in patients with chronic pain. The quadratus lumborum block (QLB) is performed in close proximity to the surface and uses a fascial compartment path to extend the distribution of local anaesthesia into the posterior abdominal wall and paravertebral space. This central effect can be of vital importance when managing the visceral pain after caesarean section.
We hypothesised that the QLB after caesarean section can provide adequate pain relief as part of a multimodal approach.
Double-blind, randomised and controlled clinical trial.
A single centre between June 2014 and December 2014.
Fifty patients who were American Society of Anesthesiologists physical status 1 or 2, with normal singleton pregnancies with a gestation of at least 37 weeks, and scheduled for elective caesarean section under spinal anaesthesia, were enrolled into the study. They were randomly assigned to receive a QLB (n = 25) with 0.125% bupivacaine 0.2 ml kg−1(Group 1) or a QLB (n = 25) with 0.9% Normal saline 0.2 ml kg−1 (Group 2).
MAIN OUTCOME MEASURES
The primary outcome measure for the study was the morphine demands and doses delivered by a patient-controlled analgesia system at predetermined intervals (1, 2, 4, 6, 12, 24 and 48 h) after surgery. The secondary endpoints were visual analogue scale (VAS) for pain at rest and on movement (dynamic), heart rate, blood pressure, pruritus, itching, nausea, vomiting and sedation.
The patients who received local anaesthetic used significantly less morphine than the control group (P < 0.001) at 6 and 12 h, but not at 24 and 48 hours after caesarean section. The local anaesthetic group had significantly less morphine demand than the control group (P < 0.001) 6, 12, 24 and 48 h after caesarean section. The VAS was significantly lower in the local anaesthetic group than the control group, including VAS for pain at rest at all times except 24 h after caesarean section, and VAS for pain on movement (dynamic) at all times.
The QLB after caesarean section was effective and provided satisfactory analgesia in combination with a typical postoperative analgesic regimen.