Cytokine response and reactive oxygen species production after low- and intermediate-risk surgery.

BACKGROUND: Cytokines are secreted locally in response to surgery and may be released into the systemic circulation. Reactive oxygen species (ROS) production is involved in various inflammatory conditions. The aims of the study were to examine the magnitude of surgical stress on the modulation of immune response and ROS production. METHODS: Patients undergoing low- and intermediate-risk surgery (n=32) were enrolled. Blood samples for tumor necrosis factor (TNF)α, interleukin (IL)1ß and IL10 assays were obtained before anesthesia, immediately after extubation, at 24 and 72 h after surgery. Measurement in whole-blood cultures of ex vivo lipopolysaccharide (LPS) and Staphylococcus aureus Cowan (SAC)-stimulated production of cytokines was carried out. The pro-oxidant potency of the whole serum was assessed in human umbilical vein endothelial cells using a fluorescent probe after stimulation by the plasma collected at the same time intervals. RESULTS: TNFα, IL1ß and IL10 did not increase significantly after surgery in either group. Whole-blood cultures response to LPS and SAC stimulation decreased for IL1ß at the end of surgery in the two groups and returned to normal within 24 h after surgery. LPS- and SAC-induced IL10 production increased significantly at 24 h in the low-risk surgery group. ROS production was greater after more stressful surgery and was correlated to morphine consumption. CONCLUSION: Cytokine release in the systemic circulation was not well correlated to the magnitude of surgical stress, whereas transient immune hyporesponsiveness was seen after moderately stressful surgery. ROS production might be a more accurate indicator of the severity of surgical trauma.

Ultra-long duration of a peripheral nerve block: a possible consequence of intraneural (subepineural) local anaesthetic injection.

A 29-year-old patient was scheduled for bilateral halllux valgus surgery and a lateral sciatic popliteal nerve block was performed on each side using ropivacaine and lidocaine using nerve stimulation. Although the sensory and motor block had usual duration on the left side, the block lasted more than 48 hours on the right side with both sensory and motor impairment. An MRI performed on day 2 on the blocked side showed extra- and intraneural fluid accumulation with cephalad and distal spread. Sensory and motor function progressively recovered within the next day and was complete on the fourth day. We postulate that this case of extremely long duration of a peripheral nerve block can be ascribed to subepineural trapping of the local anaesthetic. Part of the variability in the duration of the sensory and motor block after peripheral nerve blocks might be explained by the variable amount of drug injected intraneurally.

[Deep non-reactive reversible coma after a Mediterranean neurotoxic fish poisoning]. / Coma profond aréactif réversible après intoxication par des abats d'un poisson méditerranéen.

INTRODUCTION: Neurotoxic fish poisoning appears to be a recent phenomenon in the Mediterranean Sea. We report a case of deep non-reactive reversible coma after ingestion of Mediterranean fish innards. CASE REPORT: An 80 year-old man, heavy smoker who had a previous cerebral infarct in the posterior territory, was admitted for rapid deterioration of his neurological condition. He started having perioral tingling, then dysarthria, then became quadriparetic, then developed respiratory and hemodynamic failure and within 3-4h, entered a state of deep non-reactive coma with absence of all brainstem reflexes. He started to improve after 20 h and recovered his neurological baseline within 36 h. Later on, he stated that all his symptoms started after he ingested the gonads of a toxic fish, Lagocephalus scleratus. DISCUSSION: Tetrodotoxin blocks voltage-gated sodium channels and inhibits the production and propagation of action potentials. This toxin is highly concentrated in the liver, gonads, intestines and skin of this fish that is well-known in Japan (where it is considered as a delicacy) and South-East Asia and seems to have migrated recently to the Mediterranean Sea. There is no known antidote to tetrodotoxin but intensive supportive treatment can be life-saving.

[Audit on preoperative cardiac evaluation before non-cardiac surgery: the importance of a pocket guide to improve the anaesthesist's adhesion to ACC/AHA guidelines]. / Audit sur l'évaluation cardiaque préopératoire avant une chirurgie non cardiaque : utilité d'un aide-mémoire pour améliorer l'adhésion des anesthésistes aux recommandations de l'American College of Cardiology/American Heart Association (ACC/AHA).

INTRODUCTION: The American College of Cardiology/American Heart Association (ACC/AHA) guidelines stratify perioperative cardiac risk according to clinical markers, functional capacity, and type of surgery. They help determining which patients are candidates for preoperative cardiac testing and optimizing the cost-effectiveness of the evaluation strategy. Auditing our preoperative anaesthetic screening practice revealed an exceedingly high rate of referrals to the cardiologists. A small pocket-size reminder was created in order to improve the adhesion of the anaesthesiologists to the recommendations of the ACC/AHA, and confirm or obviate the need for a formal preoperative specialized cardiology consultation. Another audit was conducted 1 year later in order to evaluate the effectiveness of this reminder. METHODS: The second audit was conducted over a period of 1 month. Recorded data included demographic characteristics, clinical predictors of cardiovascular risk, surgical risk, and the reasons for the cardiac evaluation by a cardiologist (as reported by the senior or junior anaesthesiologist). Results of this second audit were compared to those of the audit conducted a year earlier. RESULTS: During the first audit, a total of 654 patients were seen in the preoperative unit. Fifty-two patients were referred to a cardiologist during the study period (7.9%). Guidelines for cardiac assessment were respected in 7/52 patients (13.5%). During the second audit, 30 out of 787 patients (3.8%) screened in preoperative anaesthetic consultation unit were referred to the cardiologist. According to the ACC/AHA guidelines, 27/30 patients (90%) objectively needed a cardiology consultation due to the existence of a known previous heart disease. DISCUSSION: The use of the pocket reminder concerning the ACC/AHA recommendations significantly reduced both the total number of cardiology referrals, and the number of unjustified referrals. The use of a pocket guide may help in reducing both the cost and the postponement of scheduled surgery.

[Oral contraception and hormone replacement therapy: management of their thromboembolic risk in the perioperative period]. / Contraception orale, traitement hormonal de la ménopause: risque thromboembolique et implications périopératoires.

OBJECTIVES: Many women scheduled for surgery are using either oral contraception (OC) or hormone replacement therapy (HRT). These two treatments are associated with a significant albeit moderately increased risk of venous thromboembolic events which might increase the risk associated with surgery. DATA SOURCE: Record of French and English references from Medline((R)) database. DATA EXTRACTION: Data were selected including prospective and retrospective studies, reviews, and case reports. DATA SYNTHESIS: Thromboembolism induced by these two pharmacologic classes is similar and close to that produced by pregnancy. The increased risk is usually small, especially after the first year of administration of either class of drug, for progestogen-only contraception drugs and for transdermal HRT. The increased risk should be compared with the occurrence of undesired pregnancy after discontinuation of OC or the occurrence of climateric symptoms after discontinuation of HRT. Maintaining OC during the perioperative period is legitimate and strengthening prophylaxis is justified during the first year of combined OC administration. Stressful climateric symptoms can lead to maintain HRT and strengthening prophylaxis is justified during the first year of oral HRT. Transdermal HRT may not need to be stopped and probably does not require any additional antithrombotic measure. CONCLUSION: The increased thromboembolic risk is to be compared with the risks of stopping either treatment. In most cases, these two treatments can be maintained and antithrombotic prophylaxis is moderately strengthened in particular cases.

[Organization of urgent blood transfusion in France: analysis of practice patterns in centers involved in care delivery to multiple trauma patients]. / Etat des lieux sur l'organisation de la transfusion sanguine en urgence au sein des établissements de santé français participant à la prise en charge initiale des polytraumatisés.

OBJECTIVE: To describe the organization of medical and transfusion services within the framework of hospital admission for multiple trauma. STUDY DESIGN: National survey in France. MATERIAL AND METHODS: All French hospitals caring for multiple trauma patients were sent a questionnaire. Organization of the medical and transfusion services, and their related resources were evaluated. RESULTS: Among 372 questionnaires sent, 116 replies were received from structures which care for 18 (1-500) multiple trauma patients each year. An orthopaedic and an abdominal surgery unit were widely available whereas a neurosurgeon was available in 21% of responding centers. A transfusion site was found in 43%, whereas others have either a deposit for distribution to specific patients (40%) or a small deposit to cover urgent situations (17%). Comparison with legal or expert based rules of adequate transfusion process disclosed a variable incidence of practice dysfunctions (2-49%) depending on the parameter assessed. CONCLUSION: The French organization of multiple trauma patients' care and blood transfusion delivered for these patients is not homogenous. Dysfunctions were found in all types of hospitals. Recommendations describing good practice seem necessary to be built at the national level.

Effect of vital capacity manoeuvres on arterial oxygenation in morbidly obese patients undergoing open bariatric surgery.

BACKGROUND: Arterial oxygenation may be compromised in morbidly obese patients undergoing bariatric surgery. The aim of this study was to evaluate the effect of a vital capacity manoeuvre (VCM), followed by ventilation with positive end-expiratory pressure (PEEP), on arterial oxygenation in morbidly obese patients undergoing open bariatric surgery. METHODS: Fifty-two morbidly obese patients (body mass index >40 kg m-2) undergoing open bariatric surgery were enrolled in this prospective and randomized study. Anaesthesia and surgical techniques were standardized. Patients were ventilated with a tidal volume of 10 mL kg-1 of ideal body weight, a mixture of oxygen and nitrous oxide (FiO2 = 40%) and respiratory rate was adjusted to maintain end-tidal carbon dioxide at a level of 30-35 mmHg. After abdominal opening, patients in Group 1 had a PEEP of 8 cm H2O applied and patients in Group 2 had a VCM followed by PEEP of 8 cm H2O. This manoeuvre was defined as lung inflation by a positive inspiratory pressure of 40 cm H2O maintained for 15 s. PEEP was maintained until extubation in the two groups. Haemodynamics, ventilatory and arterial oxygenation parameters were measured at the following times: T0 = before application of VCM and/or PEEP, T1 = 5 min after VCM and/or PEEP and T2 = before abdominal closure. RESULTS: Patients in the two groups were comparable regarding patient characteristics, surgical, haemodynamic and ventilatory parameters. In Group 1, arterial oxygen partial pressure (PaO2) and arterial haemoglobin oxygen saturation (SaO2) were significantly increased and alveolar-arterial oxygen pressure gradient (A-aDO2) decreased at T2 when compared with T0 and T1. In Group 2, PaO2 and SaO2 were significantly increased and A-aDO2 decreased at T1 and T2 when compared with T0. Arterial oxygenation parameters at T1 and T2 were significantly improved in Group 2 when compared with Group 1. CONCLUSION: The addition of VCM to PEEP improves intraoperative arterial oxygenation in morbidly obese patients undergoing open bariatric surgery.