Lesley I. Gilbertson

Thromboelastography: where is it and where is it heading?

Thromboelastography (TEG) has been in existence since 1948. However, it is only recently that it has made great strides into the clinical practice arena, where it is being used to assist in the diagnosis and management of coagulation problems during liver transplantation and cardiac surgery and in obstetrics. With the advent of computerization in the last decade, TEG has evolved from a research laboratory tool into a compact, user-friendly process, providing global information on the entire coagulation process. In fact, TEG is the only single test method that provides information on the balance between two important and opposing components of coagulation, namely thrombosis and lysis. The battery of traditional coagulation tests, which include bleeding time, prothrombin time (PT), partial thromboplastin time (PTT), thrombin time, fibrinogen and factor assays, and platelet function studies, are based on the isolated, static end points of standard laboratory tests. They do not take into account the interaction of clotting cascade and platelets in the whole blood. Furthermore, some of these tests can be nonspecific. For example, bleeding time has been shown to be a nonspecific indicator of platelet function. Platelet aggregation tests are expensive, laborious, and difficult to reproduce, and abnormalities cannot be used to predict risk of hemorrhage. The tests that measure clot lysis, which include fibrinogen degradation products, can be elevated in renal and hepatic disease. In contrast, hemostasis is an integrated, interactive, dynamic, and extremely complex process involving coagulation proteins, activators, cellular elements, and inhibitors. TEG measures this interactive dynamic coagulation process from the initial clotting cascade to platelet interaction and clot strengthening (via

Anesthesia for in vitro fertilization: a comparison of 1.5% and 5% spinal lidocaine for ultrasonically guided oocyte retrieval.

In many institutions, spinal anesthesia is used for surgery involving ultrasonically guided transvaginal oocyte retrieval. Because this relatively short procedure is performed on an outpatient basis, the optimal spinal technique would allow good surgical anesthesia with a short recovery time. The relative regression of equal doses of different concentrations of hyperbaric spinal lidocaine is presented. We compared 1.5% and 5% hyperbaric lidocaine (7.5% dextrose) as spinal drugs for use in this procedure. Fifty-six patients were randomized to receive 60 mg of hyperbaric solutions of either 1.5% or 5% lidocaine in combination with 10 micrograms of spinally administered fentanyl. Visual analog scale pain scores were zero throughout the procedures for all patients. There were no significant differences between the groups with regard to sensory level, maximum motor block, intravenous sedation requirements, time to two-segment regression, and time to full sensory recovery. The group receiving 1.5% lidocaine had significantly shorter times to ambulation (141 +/- 21 min vs 162 +/- 29 min; P < 0.05), voiding (147 +/- 21 min vs 174 +/- 28 min; P < 0.05), full motor recovery (86 +/- 21 min vs 111 +/- 22 min; P < 0.0001), and discharge (170 +/- 38 min vs 201 +/- 41 min; P < 0.05). The use of 1.5% hyperbaric lidocaine for transvaginal oocyte retrieval provides a significantly shorter recovery time when compared to 5% hyperbaric lidocaine and is a good choice for spinal anesthesia for this procedure.

Chloroprocaine antagonism of epidural opioid analgesia : a receptor-specific phenomenon?

Sixty healthy patients scheduled for elective cesarean delivery under epidural anesthesia were randomized to receive either lidocaine or 2-chloroprocaine as the primary local anesthetic agent. When patients first complained of postoperative pain in the recovery room, they were given either fentanyl 50 micrograms or butorphanol 2 mg, epidurally, in a randomized, blinded fashion. Postoperative analgesia, quantitated on a visual analogue scale, as well as time elapsed until first request for supplemental opioid, did not differ for patients receiving butorphanol after either 2-chloroprocaine or lidocaine anesthesia. In contrast, epidural fentanyl produced a shorter and lesser degree of sensory analgesia after 2-chloroprocaine use, whereas epidural fentanyl after lidocaine anesthesia provided pain relief similar to that seen in the butorphanol groups. Side effects were limited to somnolence with butorphanol and pruritus with fentanyl. No evidence of respiratory depression was seen in any patient. We conclude that 2 mg of butorphanol epidurally provides approximately 2 to 3 h of effective analgesia after cesarean delivery with either lidocaine or 2-chloroprocaine anesthesia. Epidural fentanyl seems to be antagonized when 2-chloroprocaine, but not lidocaine, is used as the primary local anesthetic agent. We suggest a possible mu-receptor-specific etiology for this effect.

Epidural nalbuphine for analgesia following caesarean delivery : dose-response and effect of local anaesthetic choice

The analgesic profile of epidural nalbuphine for postoperative pain relief and the impact of local anaesthetic choice upon this profile was investigated in 58 patients undergoing elective Caesarean delivery under epidural anaesthesia. Patients were randomized to receive either lidocaine 2% with 1:200,000 epinephrine or 2-chloroprocaine 3% for perioperative anaesthesia, followed by either 10, 20, or 30 mg of epidural nalbuphine administered at the first complaint of postoperative discomfort. Postoperative analgesia was quantitated on a visual analogue (VAS) scale, and by the time from the epidural opioid injection until the first request for supplemental pain medication. The duration of analgesia after lidocaine anaesthesia followed by 10, 20 or 30 mg nalbuphine was 77 (53–127) min, 205 (110–269) min, and 185 (116–241), respectively (median, 95% confidence interval, P < 0.01, 20 and 30 mg vs 10 mg). Following 2-chloroprocaine anaesthesia, VAS remained consistently elevated: the median duration of analgesia was only 30–40 min and did not differ among the three doses of nalbuphine. Side-effects consisted only of somnolence, and were noted only following lidocaine anaesthesia. Somnolence was observed in 0, 20% and 50% of those receiving 10 mg, 20 mg and 30 mg of nalbuphine respectively (NS). No evidence of respiratory depression was noted in any patient. It is concluded that 20 or 30 mg of epidural nalbuphine provides analgesia for only two to four hours following Caesarean delivery with lidocaine anaesthesia, but anaesthesia with 2-chloroprocaine resulted in minimal or no analgesia from this opioid. Nalbuphine appears to be a disappointing agent for epidural use after Caesarean delivery.RésuméNous avons évalué l’efficacité analgésique de la nalbuphine épidurale, de même que l’impact de l’anesthésique local utilisé chez 58 candidates à une césarienne élective sous anesthésie épidurale. Après randomisation, on injectait dans l’espace épidural des patientes soit de la lidocaïne 2% avec adrénaline 1:200,000, soit de la 2-chloroprocaïne 3% en taut qu’anesthésique puis 10, 20 ou 30 mg de nalbuphine à titre d’analgésique dès qu’elles se plaignaient de doulettr. On mesurait l’intensité des douleurs avec une échelle visuelle analogue (VAS) et l’intervalle entre l’injection de la nalbuphine et la réapparition de douleur nécessitant à nouveau un analgésique. Dans le groupe lidocaïne, la durée de l’analgésie avec 10, 20 ou 30 mg de nalbuphine était de (médiane, intervalle de confiance à 95%) 77 (53–127), 205 (110–269)et 185 (116–241)min, (P < 0,01, 20 et 30 mg vs 10 mg). Chez les patientes du groupe 2-chloroprocaïne, le VAS demeurait élevé malgré la nalbuphine et la durée médiane de l’analgésie était au plus de 30 à 40 min avec les trois doses de nalbuphine. Le seul effet secondaire noté consistait en de la somnolence survenue seulement chez le groupe lidocaïne à raison de 0, 20 et 50% des patientes ayant reçu 10, 20 et 30 mg de nalbuphine (NS). Aucune patiente n’a démontré de dépression respiratoire. Vingt ou trente mg de nalbuphine épidurale n’offrent qu’une ou deux heures d’analgésie après une césarienne avec de la lidocaïne comme anesthésique. Si on a utilisé de la 2-chloroprocaïne, la nalbuphine épidurale n’offre pratiquement pas d’analgésie valable. Bref, l’usage de nalbuphine par voie épidurale en tant qu’analgésique post-césarienne est décevant.

Regional anesthesia and analgesia in obstetrics.

Regional analgesia and anesthesia for obstetrical patients are undergoing revolutionary changes which will, ultimately, benefit parturients and neonates. These changes have taken place in the arena of techniques, equipment, as well as in medications. This review will cover the management techniques both for vaginal delivery and cesarean section.

Continuous Microcatheter Spinal Anesthesia With Subarachnoid Meperidine for Labor and Delivery

The patient was a 28-yr-old, white, gravida 1 para 0, 176.3-cm, 73.8-kg woman who was seen in consultation at 38 wk gestation because of a history of ”allergy to local anesthetics.” She had a history of mild asthma since childhood for which she used a metaproterenol inhaler as necessary, but had never been admitted to a hospital for treatment of asthma. She reported allergies to povidone-iodine solution, tetracycline, erythromycin, lidocaine, and “Novocaine” manifested by rash and urticaria. In addition, she reported an extrapyramidal reaction to proclorperazine. Six months earlier she had suffered an apparent allergic reaction in a dentist’s office when given a maxillary injection of local anesthetic. She developed a rash and hives on her neck, face, arms, and trunk that subsided after several hours. The