Frédéric J. Mercier

Phenylephrine Added to Prophylactic Ephedrine Infusion during Spinal Anesthesia for Elective Cesarean Section

BackgroundBecause ephedrine infusion (2 mg/min) does not adequately prevent spinal hypotension during cesarean delivery, the authors investigated whether adding phenylephrine would improve its efficacy. MethodsThirty-nine parturients with American Society of Anesthesiologists physical status I–II who were scheduled for cesarean delivery received a crystalloid preload of 15 ml/kg. Spinal anesthesia was performed using 11 mg hyperbaric bupivacaine, 2.5 &mgr;g sufentanil, and 0.1 mg morphine. Maternal heart rate and systolic blood pressure were measured at frequent intervals. A vasopressor infusion was started immediately after spinal injection of either 2 mg/min ephedrine plus 10 &mgr;g/min phenylephrine or 2 mg/min ephedrine alone. Treatments were assigned randomly in a double-blind fashion. The infusion rate was adjusted according to systolic blood pressure using a predefined algorithm. Hypotension, defined as systolic blood pressure less than 100 mmHg and less than 80% of baseline, was treated with 6 mg ephedrine bolus doses. ResultsHypotension occurred less frequently in the ephedrine–phenylephrine group than in the ephedrine-alone group: 37%versus 75% (P = 0.02). Ephedrine (36 ±16 mg, mean ± SD) plus 178 ±81 &mgr;g phenylephrine was infused in former group, whereas 54 ±18 mg ephedrine was infused in the latter. Median supplemental ephedrine requirements and nausea scores (0–3) were less in the ephedrine–phenylephrine group (0 vs. 12 mg, P = 0.02; and 0 vs. 1.5, P = 0.01, respectively). Umbilical artery p H values were significantly higher in the ephedrine–phenylephrine group than in the group that received ephedrine alone (7.24 vs. 7.19). Apgar scores were similarly good in both groups. ConclusionPhenylephrine added to an infusion of ephedrine halved the incidence of hypotension and increased umbilical cord p H.

Noncardiothoracic nonobstetric surgery in mild-to-moderate pulmonary hypertension

The anaesthetic management and follow-up of well-characterised patients with pulmonary arterial hypertension presenting for noncardiothoracic nonobstetric surgery has rarely been described. The details of consecutive patients and perioperative complications during the period January 2000 to December 2007 were reviewed. Repeat procedures in duplicate patients were excluded. Longer term outcomes included New York Heart Association (NYHA) functional class, 6-min walking distance and invasive haemodynamics. A total of 28 patients were identified as having undergone major (57%) or minor surgery under general (50%) and regional anaesthesia. At the time of surgery, 75% of patients were in NYHA functional class I–II. Perioperative deaths occurred in 7%. Perioperative complications, all related to pulmonary hypertension, occurred in 29% of all patients and in 17% of those with no deaths during scheduled procedures. Most (n = 11, 92%) of the complications occurred in the first 48 h following surgery. In emergencies (n = 4), perioperative complication and death rates were higher (100 and 50%, respectively; p<0.005). Risk factors for complications were greater for emergency surgery (p<0.001), major surgery (p = 0.008) and a long operative time (193 versus 112 min; p = 0.003). No significant clinical or haemodynamic deterioration was seen in survivors at 3–6 or 12 months of post-operative follow-up. Despite optimal management in this mostly nonsevere pulmonary hypertension population, perioperative complications were common, although survivors remained stable. Emergency procedures, major surgery and long operations were associated with increased risk.

Bacterial meningitis following combined spinal-epidural analgesia for labour: Case reports

We report a case of Streptococcus salivarius meningitis following combined spinal–epidural analgesia for labour. Although rare, bacterial meningitis following combined spinal–epidural anaesthesia is being increasingly described. We review the previously reported cases and discuss the possible aetiological causes and the aseptic precautions likely to reduce the incidence of infectious complications.

The use of a selective axillary nerve block for outpatient hand surgery

Although no guidelines concerning discharge criteria after axillary plexus block are available, many institutions consider recovery of motor function as a critical factor.With the midhumeral approach, the four main nerves of the upper extremity can be blocked separately using a peripheral nerve stimulator. The aim of this double-blind study was to block the radial (R) and musculocutaneous (MC) nerves with lidocaine, and the median (M) and ulnar (U) nerves with bupivacaine to recover motor function of the elbow and wrist more rapidly while maintaining long-lasting postoperative analgesia at the operative site. Patients undergoing surgery for Dupuytrens contracture were randomized into two groups in a double-blind fashion: in the control group (n = 17), each of the four nerves was infiltrated with 10 mL of a mixture of 2% lidocaine and 0.5% bupivacaine, whereas in the selective group (n = 17), the R and MC nerves were blocked with 10 mL of 2% lidocaine each and the M and U nerves were blocked with 10 mL of 0.5% bupivacaine each. Recovery of motor block was significantly faster in the selective group (231 +/- 91 vs 466 +/- 154 min). However, time to first sensation of pain was not different between groups (707 +/- 274 vs 706 +/- 291 min). In conclusion, this new approach at the midhumeral level enables the anesthesiologist to selectively administer local anesthetics on different nerves. Implications: In outpatients undergoing surgery for Dupuytrens contracture, a midhumeral block was used with the musculocutaneous and radial nerves blocked by lidocaine and the median and ulnar nerves blocked with bupivacaine. Recovery of motor function and time to discharge were shorter compared with patients who received the mixture on all four nerves. (Anesth Analg 1998;86:746-8)

Hetastarch co-loading is as effective as pre-loading for the prevention of hypotension following spinal anesthesia for cesarean delivery

BACKGROUND Pre-loading with hetastarch decreases the incidence and severity of hypotension after spinal anesthesia for cesarean delivery. However, pharmacokinetic studies with crystalloid predict that fluid loading should be more efficacious if rapidly administered immediately after induction of spinal anesthesia. The aim of this study was to compare pre- and co-loading of hetastarch for the prevention of hypotension following spinal anesthesia for cesarean delivery. METHODS Forty-six healthy term parturients scheduled for cesarean delivery were randomized to receive 500 mL of 6% hetastarch intravenously, either slowly before spinal anesthesia (pre-loading) or as quickly as possible immediately after spinal anesthesia (co-loading). Systolic blood pressure was maintained at or above 90% of baseline with intravenous vasopressor boluses (ephedrine 5mg/mL+phenylephrine 25 microg/mL). The primary outcome was the volume of vasopressor mix required. Secondary outcomes included blood pressure and heart rate changes, time to first vasopressor use, nausea or vomiting, and neonatal outcomes (umbilical artery and vein pH, Apgar scores). RESULTS The pre-loading group used 3.5+/-2 mL (mean+/-SD) of vasopressor mixture compared with 3.2+/-3 mL in the co-loading group (P=0.6). There were no differences in any important maternal hemodynamic or neonatal outcome values between the two study groups. CONCLUSION Hetastarch co-loading is as effective as pre-loading for the prevention of hypotension after spinal anesthesia for cesarean delivery. Surgery need not be delayed to allow a predetermined pre-load to be administered before induction of spinal anesthesia.

Epidural analgesia for labour in a parturient with neurofibromatosis.

The first report of epidural analgesia for labour in a 26-yr-old woman with von Recklinghausen’s neurofibromatosis is described. Epidural anaesthesia is often considered as contraindicated because neurofibromas may involve spinal cord and nerve roots. However, general anaesthesia was considered at high risk for this parturient on the basis of her previous medical and surgical history and of physical findings. The present observation suggests that epidural analgesia may be used in such circumstances provided that spinal cord neurofibromas have been ruled out by clinical and CT scan (or magnetic resonance imaging) examination.RésuméLes auteurs rapportent le premier cas d’analgésie péridurale pour l’accouchement chez une parturiente de 26 ans atteinte de neurofibromatose de Von Recklinghausen. L’analgésie péridurale est déconseillée voire contre-indiquée pour de nombreux auteurs en raison de la possible localisation radiculaire des neurofibromes. Cependant cette patiente a un lourd passé médicochirurgical rendant la pratique de l’anesthésie générale très risquée. Cette observation montre que l’analgésie péridurale peut être utilisée dans cette situation, à condition d’avoir éliminé par un examen clinique et radiologique (scanner ou IRM) la localisation d’un neurofibrome sur les racines lombaires correspondant à l’espace de ponction.

International consensus statement on the management of hypotension with vasopressors during caesarean section under spinal anaesthesia

1 Consultant, Department of Anaesthesia, St Michael’s Hospital, Bristol, UK 2 Professor, Department of Anesthesiology, Stanford University School of Medicine, Stanford, CA, USA 3 Professor Emeritus, Department of Anaesthesia and Peri-operative Medicine, University of Cape Town, Cape Town, South Africa 4 Senior Consultant, Department of Anaesthesia, Hamad Women’s Hospital, Doha, Qatar 5 Clinical Associate Professor, Department of Anaesthesia and Pain Medicine, King Edward Memorial Hospital for Women, Subiaco, Australia 6 Professor, D epartement d’Anesth esie-R eanimation, Hôpital Antoine B ecl ere, Clamart, France 7 Assistant Professor, Department of Anesthesiology, Washington University School of Medicine, St. Louis, MO, USA 8 Professor and Senior Consultant, Department of Women’s Anaesthesia, KKWomen’s and Children’s Hospital, Singapore 9 Chair, Department of Anesthesiology, UZ Leuven, Leuven, Belgium 10 Professor of Anesthesiology, Department of Cardiovascular Sciences, KU Leuven, Leuven, Belgium 11 Consultant, Department of Anaesthesia and Intensive Care Medicine, King’s College Hospital NHS Foundation Trust, London, UK

Transition from intrathecal analgesia to epidural anesthesia for emergency cesarean section using a combined spinal epidural technique.

Radiographic examination revealed flattening of vertebral bodies at all levels, widening of the epiphysis of long bones, and agenesis of the neck of femur. Echocardiography showed no abnormality. The patient received no premeditation. Intraoperative monitoring included electrocardiogram, noninvasive blood pressure, pulse oximetry, ETco, temperature, and neuromuscular blockade with train-of-four stimulation. Anesthesia was induced with 0, N,O, and halothane. After demonstrating that the lungs were easily ventilated with bag and mask, atracurium 5 mg was given to facilitate endotracheal intubation. Due care was taken to prevent any excessive extension of the neck. Laryngoscopy revealed partial exposure of the glottis, but with cricoid pressure a 5-mm endotracheal tube was passed in a single attempt. Ventilation was controlled and anesthesia was maintained with meperidine 5 mg intravenously, halothane 0.5%, and intermittent doses of atracurium. Surgery proceeded uneventfully for 70 min. On the operating table, flexion, extension, and rotation of the head was confined to an absolute minimum. In spite of generalized muscle hypotonia, the patient’s response to atracurium was normal. At the end of surgery, neuromuscular blockade was reversed and the trachea extubated. The patient made an uneventful recovery and was discharged on the fifth postoperative day. SDC is a rare autosomal dominent genetic disorder (1). There are only two previous reports on the anesthetic management of this disorder, one of which used regional anesthesia (23). The important possible anesthetic complications of this rare disorder are a high risk of atlantoaxial dislocation and compression of the spinal cord at Cl-2 during tracheal intubation (1). The facial manifestation of this syndrome may make laryngoscopic exposure of the vocal cords difficult. Obtaining a good mask airway may be difficult owing to a poor seal from facial asymmetry and the small chin. These patients may also have laryngotracheal stenosis (3). For a dwarf, of course, the appropriate endotracheal tube size will be smaller than that suggested for the patient’s age. Associated kyphoscoliosis with thoracic dysplasia may lead to respiratory failure in the perioperative period (2).

Preliminary evaluation of a new clinical algorithm to interpret blood cultures growing coagulase-negative staphylococci

Abstract Evaluating the clinical significance of blood cultures positive for coagulase-negative staphylococci (CoNS) is of critical importance since these microorganisms represent both the first contaminants of blood cultures and one of the leading causes of bloodstream infection (BSI). This prospective 2-centre study aimed to compare a previously reported algorithm to a clinical algorithm based on our experience. We identified 84 patients with CoNS-positive blood cultures. Twenty-seven (32%) were considered to have BSI according to our study algorithm. Thirty-seven (44%) patients were considered to have CoNS BSI according to the previously reported algorithm. The 2 algorithms isolated patients with similar rates of recurrences and hospital mortality. Our algorithm seemed to result in less diagnoses of CoNS BSI without harmful consequences compared to the previously reported algorithm. The impact on patient outcome and the inappropriate use of antibiotics deserves further investigation.