Blood pressure monitoring during arrhythmia: agreement between automated brachial cuff and intra-arterial measurements.

BACKGROUND: Since arrhythmia induces irregular pulse waves, it is widely considered to cause flawed oscillometric brachial cuff measurements of blood pressure (BP). However, strong data are lacking. We assessed whether the agreement of oscillometric measurements with intra-arterial measurements is worse during arrhythmia than during regular rhythm. METHODS: Among patients of three intensive care units (ICUs), a prospective comparison of three pairs of intra-arterial and oscillometric BP readings was performed among patients with arrhythmia and an arterial line already present. After each inclusion in the arrhythmia group, one patient with regular rhythm was included as a control. International Organization for Standardization (ISO) standard validation required a mean bias <5 (sd 8) mm Hg. RESULTS: In 135 patients with arrhythmia, the agreement between oscillometric and intra-arterial measurements of systolic, diastolic and mean BP was similar to that observed in 136 patients with regular rhythm: for mean BP, similar mean bias [-0.1 (sd 5.2) and 1.9 (sd 5.9) mm Hg]. In both groups, the ISO standard was satisfied for mean and diastolic BP, but not for systolic BP (sd >10 mm Hg) in our ICU population. The ability of oscillometry to detect hypotension (systolic BP <90 mm Hg or mean BP <65 mm Hg), response to therapy (>10% increase in mean BP after cardiovascular intervention) and hypertension (systolic BP >140 mm Hg) was good and similar during arrhythmia and regular rhythm (respective areas under the receiver operating characteristic curves ranging from 0.89 to 0.96, arrhythmia vs regular rhythm between-group comparisons all associated with P>0.3). CONCLUSIONS: Contrary to widespread belief, arrhythmia did not cause flawed automated brachial cuff measurements.

Increased ß2-adrenergic vasorelaxation at the early phase of endotoxemic shock in rats.

BACKGROUND AND PURPOSE: The early management of the cardiovascular dysfunction of septic shock is critical as it is associated with a poor outcome. Although the use of catecholamines is a common therapy in this syndrome, no data are available on the involvement of ß-adrenoceptor (ß-AR) subtypes and only few studies report an alteration of ß-adrenergic-induced vasodilation in septic shock. The purpose of the study was to evaluate vascular ß1, ß2 and ß3-AR expression and function in an endotoxemic rat model. EXPERIMENTAL APPROACH: Endotoxemia was induced in rats by intravenous injection of lipopolysaccharide (LPS). ß1, ß2 and ß3-AR mRNA expression was evaluated by RT-PCR in aorta and vascular ß1, ß2 and ß3-AR responses were determined on conducting (aorta) and/or resistance (mesenteric and renal) arteries by constructing relaxation curves in response to different ß-AR agonists. RESULTS: The maximal effect of isoproterenol decreased by 31 to 61% in the three vascular beds of LPS-treated rats compared to controls. In aortas from LPS-treated rats, ß1 and ß3-AR mRNA expression was decreased and associated to a reduced ß1 and ß3-induced vasodilation. Conversely, albeit ß2-AR mRNA was unchanged, the maximal ß2-AR-induced vasodilation increased by 49% in aortas from LPS-treated rats compared to controls. This increase was not affected by endothelium removal but was abolished in the presence of a ß2-AR antagonist or an adenylate cyclase inhibitor. CONCLUSIONS: In endotoxemia, ß2-AR vasodilation was increased by a potential recruitment of ß2-AR located on smooth muscle cells. This study suggests that vascular ß2-AR should be a putative new therapeutic target in septic shock.

[Epidemiology of cerebral perioperative vascular accidents]. / Épidémiologie des accidents vasculaires cérébraux périopératoires.

OBJECTIVES: Stroke is a well-described postoperative complication, after carotid and cardiac surgery. On the contrary, few studies are available concerning postoperative stroke in general non-cardiac non-carotid surgery. The high morbid-mortality of stroke justifies an extended analysis of recent literature. ARTICLE TYPE: Systematic review. DATA SOURCES: Firstly, Medline and Ovid databases using combination of stroke, cardiac surgery, carotid surgery, general non-cardiac non-carotid surgery as keywords; secondly, national and European epidemiologic databases; thirdly, expert and French health agency recommendations; lastly, reference book chapters. RESULTS: In cardiac surgery, with an incidence varying from 1.2 to 10% according to procedure complexity, stroke occurs peroperatively in 50% of cases and during the first 48 postoperative hours for the others. The incidence of stroke after carotid surgery is 1 to 20% according to the technique used as well as operator skills. Postoperative stroke is a rare (0.15% as mean, extremes around 0.02 to 1%) complication in general surgery, it occurs generally after the 24-48th postoperative hours, exceptional peroperatively, and 40% of them occurring in the first postoperative week. It concerned mainly aged patient in high-risk surgeries (hip fracture, vascular surgery). Postoperative stroke was associated to an increase in perioperative mortality in comparison to non-postoperative stroke operated patients. CONCLUSION: Postoperative stroke is a quality marker of the surgical teams' skill and has specific onset time and induces an increase of postoperative mortality.

[Argatroban, a new antithrombotic treatment for heparin-induced thrombocytopenia application in cardiac surgery and in intensive care]. / L'argatroban, nouvel antithrombotique pour la thrombopénie induite par l'héparine en chirurgie cardiaque de l'adulte: utilisation en chirurgie cardiaque et en réanimation.

OBJECTIVES: Although heparin-induced thrombocytopemia (HIT) is uncommon, its thromboembolic complications are potentially life-threatening. The low-molecular weight heparins are less responsible of HIT than unfractionated heparin (UFH) but this latter is still indicated in some circumstances such as cardiac surgery. Argatroban, a selective thrombin inhibitor, recently available, has been indicated in HIT treatment. This review presents the main pharmacological characteristics, its indications and uses in the context of cardiac surgery and in intensive care medicine. METHODS: Review of the literature in Medline database over the past 15 years using the following keywords: argatroban, cardiac surgery, circulatory assistance, cardiopulmonary bypass. RESULTS: Despite its short-acting pharmacokinetic, argatroban cannot be recommended during cardiopulmonary bypass. On the contrary, argatroban is indicated in many circumstances in postoperative period of various cardiac surgeries (on-pump, off-pump, circulatory assistance). Nevertheless, after cardiac surgery, doses have to be adapted according to coagulation laboratory testing (ACT), particularly in patients presenting acute organ failure (kidney injury, heart failure, liver failure). This compound has no antagonist and is excluded during severe hepatic failure. The continuous intravenous administration is a drawback. CONCLUSION: Argatroban is a new direct competitive thrombin inhibitor well evaluated as treatment of HIT after cardiac surgery. In HIT management, argatroban is an interesting alternative to lepirudin that is not anymore available and danaparoid because of supply disturbances.

Risk factors and pathogens involved in early ventilator-acquired pneumonia in patients with severe subarachnoid hemorrhage.

Ventilator-acquired pneumonia (VAP) is a common burden in intensive care unit (ICU) patients, but, to date, specific data are not available in patients with severe aneurysmal subarachnoid hemorrhage (SAH). A single neuro-ICU retrospective analysis of 193 patients with SAH requiring mechanical ventilation (MV) ≥48 h admitted from January 2005 to May 2010 was undertaken. The diagnosis of early VAP was prospectively upheld during a multidisciplinary staff meeting, according to the American Thoracic Society (ATS) 2005 guidelines with a threshold of 7 days after the onset of MV. Patients had a median age of 53 (44-62) years and 70 (36 %) were male. The median Glasgow coma scale (GCS) score before MV was 9 (5-14). 142 (74 %) patients had a World Federation of Neurosurgeons (WFNS) score ≥III. Aneurysm was secured with an endovascular coiling procedure in 162 (84 %) patients. 81 (48.7 %) patients declared an early VAP. On multivariate analysis, male sex (odds ratio [OR] 2.26, 95 % confidence interval [CI] [1.14-4.46]), use of mannitol before day 7 (OR 3.03, 95 % CI [1.54-5.95]), and achieving enteral nutrition ≥20 kcal kg(-1) day(-1) after day 7 (OR 2.91, 95 % CI [1.27-6.67]) remained independent risk factors of VAP. The main pathogens involved were methicillin-susceptible Staphylococcus aureus (MSSA) (34.9 %), Haemophilus influenzae (28.1 %), Streptococcus pneumoniae (15.5 %), and Enterobacteriaceae (10.7 %). Early VAP was associated with a longer duration of MV and ICU stay, but not with an excess of mortality. Early VAP bears significant morbidity in patients with severe SAH. Pathogens involved in early VAP are susceptible to antibiotics. Among modifiable risk factors of VAP, early enteral nutrition could be an easy and effective target.

Propofol versus thiopental by target controlled infusion in patients undergoing craniotomy.

BACKGROUND: For decades thiopental has been considered as the hypnotic drug of choice for intracranial surgery. However, total intravenous anesthesia performed with thiopental is associated with delayed recovery, whereas early post-operative neurological evaluation is critical. For this reason, target controlled infusion (TCI) of propofol is increasingly used for maintenance of anesthesia. However, a thiopental TCI has never been assessed for this purpose. We tested the hypothesis that a thiopental TCI provides an acceptable way to achieve early recovery compared to a propofol TCI during supratentorial surgery. METHODS: Eighty patients undergoing elective craniotomy for a supratentorial tumor were randomized to receive either a propofol TCI (group P) or a thiopental TCI (group T). Both groups received a sufentanil TCI and the bispectral index was monitored. The primary end-point was time to tracheal extubation. Secondary end-points were per- and post-operative hemodynamics as well as respiratory and recovery parameters. Assessment of study end-points was performed by an intensive care specialist blinded (like the patient) to the received hypnotic. RESULTS: Time to extubation was significantly (P<0.0001) shorter in group P (median 149 minutes; interquartile range 72-250 minutes) than in group T (median 453 minutes; interquartile range 286-813 minutes). Similarly, the recovery parameters were significantly better in group P than in group T. There was no difference between groups in terms of patient characteristics and hemodynamic parameters. CONCLUSION: Even with TCI and bispectral index monitoring, thiopental is associated with an inappropriate delayed recovery from supratentorial surgery compared to propofol TCI.

[Perioperative adverse events related to antidepressive agents use]. / Complications liées à l'utilisation périopératoire des médicaments antidépresseurs.

OBJECTIVE: Depression is the most common psychiatric disease, which is treated by the use of antidepressive agents possessing various mechanisms of action. Thus, the use in preoperative period of antidepressive agents is frequent (7% of patients scheduled for surgery). The objective of this review was to update the knowledge on the drug interactions between antidepressive agents and drugs used in perioperative period. METHODS: (i) Medline and Ovid databases using combination of antidepressive agent and perioperative period as keywords; (ii) national and European epidemiologic database; (iii) expert recommendation and official French health agency; (iv) reference book chapters. RESULTS: The clinical practice showed a limited risk of adverse event related to antidepressant agents interaction with perioperative used drugs. In the two past decades, few relevant observations of adverse event related with imipramine and monoamine oxidase inhibitors use was reported. The most recent antidepressive agents had no serious adverse interaction. Nevertheless, the serotonin syndrome has to be known as far as it is more and more reported. In case of hypotension, the use of vasopressive agent has to be careful because of excessive response.

[High-flow nasal oxygen for severe hypoxemia after cardiac surgery]. / Oxygénation nasale à haut débit pour hypoxémie après chirurgie cardiaque.

OBJECTIVES: High-flow nasal oxygen (Optiflow™) is validated in paediatric intensive care but not in adults' patients for severe hypoxemia. The aim of this study was to evaluate this oxygen system delivery in adults' patients for postoperative hypoxemia after cardiac surgery. STUDY DESIGN: Prospective, open study for evaluation of medical practice. PATIENTS AND METHODS: Patients operated upon for cardiac surgery with immediate postoperative hypoxemia characterized by SpO(2) <0.96 with 50% oxygen with a Venturi mask were treated with the high-flow nasal oxygen system (O group) when it was available or with the classical high-flow oxygen face mask (M group). Gas exchanges were measured at the end of the surgery, at the beginning of the treatment and 1 hour, 6 hours after the inclusion and at day 1 and 2 post-treatment. Parameters studied were: duration of hypoxemia, duration of ICU stay, postoperative pneumonia occurrence, requirement of re-intubation, non invasive ventilation and catecholamine. Tolerance was evaluated with measurement of pain (visual scale), satisfaction (visual scale), and dryness of mouth. RESULTS: Forty patients were included, 19 in group O, 21 in group M. Patient's characteristics did not differ between the two groups before treatment. There were no significant differences between groups for duration of hypoxemia (3.8±2.2 days in O group versus 4.3±2.3 days in M group), duration of hypoxemia, duration of ICU stay, postoperative pneumonia occurrence, requirement of re-intubation, non invasive ventilation and catecholamine. Pain was not significantly different between groups, satisfaction was better (P<0.001) and mouth drier (P<0.001) in group O than in group M. CONCLUSION: These results give good arguments for an improvement in gas exchange and better tolerance of high-flow nasal oxygen (Optiflow™) versus classical high-flow oxygen face mask in postoperative cardiac patients. These results must be confirmed by a randomised study with a larger population.

[Remote cerebellar hemorrhage]. / Hémorragie cérébelleuse à distance.

Intracerebral hemorrhage remote from the site of surgery is an infrequent complication after neurosurgical procedures. Cerebellar hemorrhage after supratentorial craniotomy is the most commonly described pattern of remote hemorrhage unknown by the anesthesiologist. It is linked with a frequent morbidity and mortality. We report a case of this complication after meningioma surgery with a favorable outcome.

[Intra-aortic balloon pumping and heparin-induced thrombocytopenia]. / Contre-pulsion par ballonnet intra-aortique et thrombopénie induite par l'héparine non fractionnée.

Thrombocytopenia is frequently reported in the presence of intra-aortic balloon pumping (IABP) after cardiac surgery and in cardiology, but heparin-induced thrombocytopenia (HIT) is rarely responsible of it in this circumstance. A case-report if HIT in a patient with IABP is presented. This case emphasised the difficulty in diagnosis of HIT in this situation. An acute decrease in platelet count lasting after removal of IABP could suggest the diagnosis of HIT when other origins for thrombocytopenia are excluded.

[Use of heparin and platelet GPIIbIIIa inhibitor tirofiban for cardiac surgery in patients for suspicion of heparin-induced thrombocytopenia]. / Chirurgie cardiaque effectuée avec une association héparine non fractionnée et inhibiteur des récepteurs GPIIbIIIa plaquettaire (tirofiban) pour suspicion de TIH.

In a patient with heparin-induced thrombocytopenia few antithrombotic alternate treatments are proposed for cardiac surgery with or without cardiopulmonary bypass: danaparoid, lepirudine or powerful antiplatelet agent. Recently, the platelet GPIIbIIIa antagonist tirofiban (Aggrastat) was tested in humans. We reported two cases of patients operated upon for cardiac surgery with unfractionnated heparin (UFH) and tirofiban. The first patient underwent an off-pump coronary artery bypass graft and the second one a mitral valvular replacement under cardiopulmonary bypass. Tirofiban was associated with UFH and aprotinine. Postoperative bleeding was in the normal range for the two types of surgeries and haemodynamic tolerance was good. These two case reports support the possibility of secure cardiac surgery under efficient platelet inhibition with tirofiban. The management of cardiac surgery with tirofiban without monitoring of platelet aggregation appeared to be more simple than with the other alternate antithrombotic agents.

[Is training on basic skills and management of critical events responsible of ethical considerations in anaesthesia and intensive care?]. / L'apprentissage des gestes invasifs et de la gestion d'une situation critique pose-t-il des problèmes éthiques en anesthésie-réanimation?

OBJECTIVE: To provide information on morbidity and ethical questions associated with learning of invasive techniques (tracheal intubation, positioning of central venous or epidural catheters) and management of anaphylactic shock. STUDY DESIGN: Retrospective survey. METHODS: Written questionnaire to 54 anaesthesiologists and 55 residents. RESULTS: Training was primarily performed by residents having a 6 months-experience for general anaesthesia and by more experienced residents for epidural analgesia. Residents observed first two or three procedures performed by seniors, but did not have theoretical lectures in 30 to 50% of cases. Dead bodies or manikins were rarely used. Despite the presence of experienced anaesthesiologists during the first attempts, there was a high morbidity rate which was considered by 22 to 37% of the interviewed anaesthesiologists a loss of benefit for the patients. Despite a high level of coaching, a high morbidity rate was associated with the first attempts. However, only few residents explicitly stated to be concerned by ethical questions. Among anaesthesiologists, who had yet to manage anaphylactic shock, 21 and 35% of them reported that diagnostic and treatment could have been performed faster. Virtual learning was misunderstood but 46% of anaesthesiologist described numerous advantages in using simulator of anaesthesia. CONCLUSION: Despite an apparent morbidity with a loss of benefit, informed consent of the patients were rarely obtained.

[Butyrylcholinesterase deficiency: how to analyse the cholinesterase activity in small children?]. / Déficit génétique de la butyrylcholinestérase: comment interpréter l'activité cholinestérasique chez le jeune enfant ?

We report the case of a prolonged neuromuscular blockade in an 18-month-old age girl following administration of a usual dose of succinylcholine. The diagnosis was highly suggested by the clinical history while cholinesterase activity was included in adult normal values but below values of a personal series of 41 small children. The familial analysis of dibucaine and fluoride number confirmed the hypothesis of an atypical variant (AA phenotype). The cholinesterase activity is higher in small children than in adult and has to be analysed according to the age.

[Body mass index and albuminemia in patients under mechanical circulatory assistance before cardiac transplantation]. / Indice de masse corporelle et albuminémie péri-implantatoires de patients sous assistance circulatoire mécanique (ACM) en attente d'une transplantation cardiaque.

OBJECTIVE: To evaluate the prognostic influence of peri-implantation nutritional status of patients under mechanical circulatory assist (MCA) prior to cardiac transplantation (CT). STUDY DESIGN: Retrospective analysis of patients with cardiogenic shock included from June 1997 to December 2002. PATIENTS AND METHODS: Evaluation at MCA's implantation, at day (D) 30 and at CT or patient's death (D) of body mass index (BMI=body weight (kg)/size (m(2)), albuminemia (Alb g/l), expressed as median values (med) and range (min-max). Odds ratio (OR) and CI 95%) were calculated. A multivariate analysis was performed to determine variables related to D or CT success. RESULTS: Thirty-four patients (30 men), median age 40.5 years (10-63), were included. MCA types were cardiac pumps (N=3); pneumatic (N=18) or electric (N=5) ventricular assist devices and artificial heart (N=8). Global mortality was 56% (19 over 34 patients) and at implantation in the global population (N=34) BMI was 19.4 (9.3-28.1) and Alb 24.6 g/l (15-37.5). At MCA's implantation and D30 respectively, 38 and 42% of the patients had a severe hypoAlb (Alb<30 g/l) and a BMI<19 attesting of a seriously deteriorated nutritional status. No significant statistical difference was observed on median BMI of transplanted patients T (N=15) and expired patients D (N=19). Alb was significantly different (p<10(-4)) between T and D patients: median Alb: 30 g/l (20-37.5) in T patients, 20 g/l (15-31) in D patients. HypoAlb<21 g/l was an independent prognostic factor of death (p=0.004; OR: 0.541; IC95% : 0.36-0.82) and Alb>33 g/l an independent prognostic factor of CT success (p=0.003; OR:1.38; IC95% : 1.12-1.71). CONCLUSION: These results seem to demonstrate that at MCA implantation, a seriously deteriorated albuminemia level (<30 g/l) negatively impacts patients overall survival after CT.