Deborah J. Stein

The Effectiveness of Video Technology As an Adjunct to Teach and Evaluate Epidural Anesthesia Performance Skills

Background Although video review has been used in teaching, it has not been reported for use as an adjunct to teaching anesthesiology residents. The purpose of the prospective, randomized, blinded study was to determine whether teaching with video review improves epidural anesthesia skills of anesthesiology residents. Methods Twenty-two second-year (CA-2) anesthesiology residents beginning their first obstetric anesthesia rotation were assigned to video or nonvideo groups. All residents were filmed daily as they placed epidural analgesia. Residents assigned to the video group reviewed their tapes twice a week with an attending anesthesiologist, whereas residents assigned to the nonvideo group never saw their films. Four experienced attending anesthesiologists independently judged videotapes taken on days 1, 15, and 30 and scored the residents for “overall” skill (range of summed overall grades, 0–40), as well as on 13 predetermined criteria. Results As determined by kappa coefficients, interrater reliability was high among the judges (k = 0.7–0.8). Residents in the video group improved to a greater degree than residents in the nonvideo group. On day 1, the median overall grades for the video and nonvideo groups were 21 and 12, respectively. By day 15, the corresponding grades had increased to 32 and 24, respectively (P < 0.01). However, overall median grades continued to improve between days 15 and 30 in the video group only (P < 0.01). Conclusions Review of resident videotapes resulted in greater improvement in overall and predetermined performance criteria. In addition, video review was helpful in identifying skills that were inadequately learned, thus allowing for specific teaching in those areas.

Comparison of the effects of sevoflurane and isoflurane anesthesia on the maternal-fetal unit in sheep

PurposeThe aim of this study was to determine the hemodynamic and blood gas effects of inhalational anesthetics on the maternal-fetal sheep unit. The principal hypothesis, tested in chronically instrumented near-term pregnant ewes, was that sevoflurane anesthesia may be safe and useful for the mother and fetus during pregnancy, compared with isoflurane.MethodsSix chronically instrumented pregnant and 3 nonpregnant ewes were tested repeatedly to establish the minimum alveolar concentration (MAC) for sevoflurane and isoflurane to be used in the hemodynamic and blood gas studies. Progressively increasing concentrations of sevoflurane or isoflurane in oxygen were administered to 12 pregnant ewes. Uterine blood flow, maternal and fetal heart rates, blood pressure, arterial blood gases, and intra-amniotic pressure were subsequently measured.ResultsThe MAC of sevoflurane was 1.52 ± 0.1 15% and 1.92 ± 0.17% in pregnant and nonpregnant ewes, respectively; while the MAC of isoflurane in the pregnant and nonpregnant sheep was 1.02 ± 0.12% and 1.42 ± 0.19%, respectively. In both the sevoflurane and isoflurane groups, changes in maternal and fetal blood gases were minimal during exposure to low-dose (0.5–1.0 MAC) inhaled concentrations. Although uterine blood flow was maintained and the fetus remained well oxygenated at higher concentrations of both agents (2.0 MAC of either agent), the agents produced decreases in maternal and fetal arterial pressure.ConclusionA “low-dose” concentration (0.5–1.0 MAC) of sevoflurane may be safe and useful for both mother and fetus during near-term pregnancy. However, a high concentration (1.5–2.0 MAC) of sevoflurane or isoflurane may induce hemodynamic instability in the mother and fetus when administered.

The effect of intrathecal analgesia on the success of external cephalic version

External cephalic version (ECV), the procedure whereby a fetus in the breech position is converted to vertex, is often performed to avoid an operative delivery. Potential benefits of epidural and spinal anesthesia for this procedure are controversial. Several previous studies have evaluated the use of epidural anesthesia with varying results. We sought to determine whether analgesia produced by subarachnoid sufentanil would safely improve the success of ECV. Patients who received subarachnoid analgesia (n = 20) were compared with those who did not (n = 15) in regard to success of ECV, level of pain during ECV, and satisfaction. ECV was successful in 21 patients (60%), with more frequent success in women who received spinal analgesia as compared with those who did not (80% vs 33%, respectively;P = 0.005). Patients who received spinals also reported smaller pain scores and were more satisfied with ECV. None of the women who received spinal analgesia developed a postdural puncture headache, and the only case of fetal bradycardia occurred in a patient who did not receive spinal analgesia. More profound patient comfort after spinal analgesia may have permitted greater manipulation of the abdomen during ECV, thus improving success rates of ECV without increasing risk.

Cocaine screening of parturients without prenatal care: an evaluation of a rapid screening assay.

Illicit drugs are used widely by inner city patients in our society.Because cocaine ingestion can produce life-threatening arrhythmias and interact with anesthetic drugs, it is potentially useful for the anesthesiologist to know a high-risk patients cocaine status before administering anesthesia. The commonly used methods to detect cocaine abuse, however, often require 1-3 days for laboratory processing. With these tests, anesthesiologists are unable to test for recent cocaine use in an emergency setting. A new rapid latex agglutination assay for urinary metabolites of cocaine (OnTrak[R] Abuscreen[TM]; Roche Diagnostic Systems Inc., Branchburg, NJ) was compared with an assay used by many hospital laboratories. The prevalence of cocaine abuse in the group of unregistered parturients was found to be 68%, with the latex agglutination results exactly matching the hospital laboratory results (kappa = 1.0). A sensitive and specific method now exists that allows anesthesiologists to assess cocaine use rapidly, so that they can use this information when planning a patients anesthetic. (Anesth Analg 1997;84:76-9)

A Comparison of Espocan® and Tuohy Needles for the Combined Spinal-epidural Technique for Labor Analgesia

When using the needle-through-needle combined spinal-epidural (CSE) technique for labor analgesia, failure to obtain cerebrospinal fluid (CSF), paresthesias, and intrathecal or intravascular migration of the catheter are of concern. Epidural needles with spinal needle apertures, such as the back-hole Espocan® (ES) needles, are available and may reduce these risks. We describe the efficacy and adverse events associated with a modified epidural needle (ES) versus a conventional Tuohy needle for CSE. One-hundred parturients requesting labor analgesia (CSE) were randomized into 2 groups: 50—ES 18-gauge modified epidural needle with 27-gauge Pencan® atraumatic spinal needle, 50—conventional 18-gauge Tuohy needle with 27-gauge Gertie Marx atraumatic spinal needle. Information on intrathecal or intravascular catheter placement, paresthesia on introduction of spinal needle, failure to obtain CSF through the spinal needle after placement of epidural needle, unintentional dural puncture, and epidural catheter function was obtained. No intrathecal catheter placement occurred in either group. Rates of intravascular catheter placement and unintentional dural puncture were similar between the groups. Significant differences were noted regarding spinal needle-induced paresthesia (14% ES versus 42% Tuohy needles, P = 0.009) and failure to obtain CSF on first attempt (8% ES versus 28% Tuohy needles, P < 0.02). Use of ES needles for CSE significantly reduces paresthesia associated with the insertion of the spinal needle and is associated with more frequent successful spinal needle placement on the first attempt.

The substance-abusing parturient: Implications for analgesia and anaesthesia management

Substance abuse remains a major problem in society, while substance abuse in pregnancy has emerged as a major health problem in the 1990s. Due to this trend, obstetricians, neonatologists and anaesthesiologists are encountering an increasing number of pregnant patients who use licit and illicit substances. The use of these substances presents a multitude of problems for the patient, her unborn child, and the physicians involved in their care. The following article reviews the various substances of abuse use by pregnant women and the implications of their use for analgesia and anaesthesia during labour and delivery. In conclusion, it is essential for physicians to identify the substance abusing parturient to optimize care of these patients and be prepared for the crises that may arise.