Continuous spinal anesthesia for cesarean section in a parturient with severe recurrent peripartum cardiomyopathy.

The anesthetic management of labor and delivery in patients with peripartum cardiomyopathy is not well defined. Using continuous spinal anesthesia in such a rare clinical situation has not been previously reported. A patient with recurrent peripartum cardiomyopathy presented in congestive heart failure for emergent cesarean section. Continuous spinal anesthesia was successfully employed as the anesthetic technique for the procedure. In addition, it also markedly reduced the patient's symptoms. Continuous spinal anesthesia is a reliable, rapidly titratable technique, which provides excellent analgesia with minimal undesirable hemodynamic changes for patients with peripartum cardiomyopathy undergoing cesarean delivery.

Combined spinal and epidural anesthesia for labor and cesarean delivery in a patient with Guillain-Barre syndrome.

BACKGROUND AND OBJECTIVES: The anesthetic management of labor, delivery, and cesarean delivery in patients with active or resolving Guillain-Barre syndrome is not well defined. Using a combined spinal and epidural (CSE) technique in such a rare clinical situation has not been previously reported. CASE REPORT: A 32-year-old woman gravida 2, para 0 was diagnosed with Guillain-Barre syndrome at 21 weeks of pregnancy. Paralysis spread up to the T4 level. Three months later, she was admitted for labor at term. She presented in severe labor pain and it was decided to proceed with CSE analgesia. No unusual hemodynamic instability, signs of autonomic dysfunction, or increased sensitivity to local anesthetics was noted. After several hours, delivery by cesarean section was required and epidural anesthesia was then used. The patient had an uncomplicated postpartum course. CONCLUSION: Careful evaluation and documentation of the patient's baseline neurological status, a thorough discussion with the patient regarding the risks and benefits of the technique for labor analgesia, and an appreciation of the limited experience with this kind of clinical situation are important.

Regional anesthesia and local anesthetic-induced systemic toxicity: seizure frequency and accompanying cardiovascular changes.

We sought to determine the contemporary frequency of seizures, and the associated cardiovascular changes, resulting from local anesthetic-induced seizures in all patients undergoing brachial plexus, epidural, and caudal regional anesthetics. We investigated the following variables: development and treatment of seizure or cardiac arrest during the regional anesthetic, type of anesthetic (including local anesthetic used), gender, age, ASA physical status class and type of operation (elective or emergent). In addition, each patient who experienced a seizure underwent retrospective review of the acute event to determine the arterial blood pressure and heart rate changes accompanying the seizure, as well as details of the regional block technique. There was a significant difference between the rate of seizure development between epidural, brachia, and caudal anesthetics, with caudal > brachial > epidural. A significant difference was also noted in the rate of seizure development within types of brachial block, with supraclavicular and interscalene > axillary. No adverse cardiovascular, pulmonary or nervous system events were associated with any of the seizures, including the 16 patients who received bupivacaine blocks. The frequency of local anesthetic-induced seizures stratified by block type has a wide range, and cardiovascular collapse after bupivacaine-associated seizure has a low incidence.

Fetal heart rate variability and cerebral oxygen consumption in fetal sheep during asphyxia.

This study was designed to examine the relationship between fetal heart rate variability and fetal cerebral oxygen uptake. Fetal sheep were chronically prepared with catheters and electrodes to determine cerebral blood flow (microsphere method), cerebral arteriovenous oxygen difference, and the electrocardiogram. An adjustable occluder was placed on the maternal common internal iliac artery to induce fetal asphyxia by reducing uterine blood flow. Fetal heart rate variability tended to decrease in the first 11 min of asphyxia, when cerebral oxygen consumption was approximately 53% of control. Despite stable cerebral oxygen consumption and worsening metabolic acidosis, however, fetal heart rate variability progressively returned towards normal by 36 min. There was no relationship between the depression of FHR variability and the degree of reduction of cerebral oxygen consumption. Nor was there any relationship between an alteration in regional cerebral blood flow or myocardial blood flow and the return of FHR variability with increasing duration of asphyxia. We conclude that there is an association between loss of fetal heart rate variability and reduced cerebral oxygen consumption, but the reduced variability does not persist with time at this degree of reduced cerebral metabolism in fetal sheep. This appears to be at variance with human clinical experience. Among the explanations for this may be insufficiently severe asphyxia, a species difference, removal of an inhibitor to FHR variability, or progressive use of other substrates for metabolism.

Prolongation of lidocaine spinal anesthesia with epinephrine and phenylephrine.

The effect of vasoconstrictors on the duration of lidocaine spinal anesthesia is controversial. We conducted a double-blind study of 28 neurologically normal ASA Class I or II patients to determine the effect of vasoconstrictors (epinephrine and phenylephrine) on the duration of lidocaine spinal anesthesia. The patients were randomized into three groups. All patients received 1.2 mg lidocaine per inch body height, mixed with 0.5 ml of test solution. Group 1 patients received lidocaine plus 0.5 ml normal saline; Group 2 patients received lidocaine plus 0.3 mg epinephrine; Group 3 patients received lidocaine plus 5 mg phenylephrine. Segmental sensory blockade was assessed by pinprick at 2-min intervals for the first 20 min and then every 5 min thereafter. Mean highest level was between T-2 and T-3 for all 3 groups. Time from injection to highest sensory level was similar in Groups 1 and 3, 11.6 +/- 3.57 and 12.0 +/- 5.10 min, respectively, but was significantly prolonged in Group 2, 18.1 +/- 4.33 min. Time for regression by two sensory dermatomes were significantly prolonged in both Groups 2 and 3, 102.9 +/- 18.1 and 105.7 +/- 33.1 min, respectively, compared to 78.1 +/- 12.6 min in Group 1. Times for regression to T-12 was also significantly prolonged in both Groups 2 and 3, 153.7 +/- 27.6 and 156.8 +/- 26.7 min, respectively, compared to 117.71 +/- 10.0 min in Group 1. In the doses used in the present study, both epinephrine and phenylephrine significantly prolong the duration of lidocaine spinal anesthesia.