Gertie F. Marx

Computer Analysis of Postanesthetic Deaths

Of 34,145 consecutive surgical patients who were attended by an anesthesiologist, 645 died within the first seven days. Two prime determinants of mortality emerged: 1) the physical status of the patient, and 2) the judgment and skill of the physicians. Mortality was highest in cardiovascular and brain surgery, in patients of advanced age, and in emergency surgery. However, this was principally a reflection of the higher incidences of poor-risk patients in these groups. Mortality was highest with local anesthesia, lowest with regional analgesia, and intermediate with general anesthesia. Again, this was mainly an expression of the numbers of poor-risk patients anesthetized with the particular methods. Four per cent of the deaths (1:1,265 cases) were related to anesthetic management and 3 per cent (1:1,707 cases) to postoperative management. Deaths attributable to anesthesia occurred as late as the sixth postoperative day, and two-thirds were judged preventable.

First-Trimester Drug Use and Congenital Disorders

The authors determined the prevalence of certain major congenital disorders among live-born infants of 6509 mothers in a prepaid health plan for the 30-month period of January 1, 1980 through June 30, 1982 who used a wide variety of drugs during the first timester of pregnancy. The results were similar to those obtained in this population in a prior 30-month study. No strong associations between any of the commonly used drugs and the congenital disorders studied were present.

Biochemical status and clinical condition of mother and infant at cesarean section.

URATION of general anesthesia prior to D delivery is an important factor influencing the depression of the infant born by cesarean section. In a study of 173 elective cesarean sections performed under nitrous oxide-succinylcholine anesthesia (with or without thiopental induction) , Finster and Poppers1 found a mean anesthesia duration of 22.7 minutes in neonates with 1-minute Apgar scores of 6 or less as compared to 17.1 minutes in neonates scoring 7 or better.

Placental Transmission of Nitrous Oxide

Placental transmission of nitrous oxide Was studied in 14 patients during elective cesarean section and in 26 patients during vaginal delivery. Duration of ancsthesia varied between 2, and 19 minutes. Randomly-selected patients were hyperor hyporcntilated. Umbilical vein nitrous oxide levels ranged from 55 to 91 per cent of maternal values (average 79 per cent). The fetal-maternal nitrous oxide concentration ratio showed no correlation with incidence of uterine contractions, duration of anesthesia (after the first two minutes), or materanal pH (7.32–7.59) or Paco2 (14–41 torr). Umbilical artery nitrous oxide levels ranged from 31 to 90 per cent of the umbilical vein levels. The umbilical artery-vein nitrous oxide concentration ratio increased progessivcly with increasing durations of anesthesia. The data demonstrate rapid transmission of nitrous oxide across the human placenta as well as rapid uptake by the fetus.

Changing Mallampati score during labour

We present the case of a changing Mallampati score during the course of labour in a healthy primigravida. On admission to hospital, the airway was assessed as Mallampati class I–II. At 5 cm cervical dilation, the woman began to bear down strenuously and continued this despite being advised of the inherent hazard. At 8 cm dilation, Caesarean delivery was contemplated because of fetal heart rate decelerations. Repeat airway evaluation revealed marked oedema of the lower pharynx giving rise to a Mallampati score of III–IV. Improvement of the fetal heart rate tracing permitted vaginal delivery under local infiltration. Postpartum, the Mallampati score was still III–IV However, 12 hr later it had returned to the admission classification of I–II. We recommend that, in addition to the usual airway evaluation on admission, the assessment be repeated in the obstetric patient before induction of general anaesthesia.RésuméNous présentons un cas de variation du score de Mallampati pendant le travail d’une primigeste bien portante. A l’admission, son airway est classé I–II sur l’échelle de Mallampati. Avec une dilatation cervicale de 5 cm, la patiente se met à pousser vigoureusement malgré sa connaissance du danger inhérent à un tel effort. A 8 cm de dilatation, on envisage une césarienne pour cause de décélérations du coeur foetal. Des évaluation répétées de l’airway révèlent un oedème important du pharynx inférieur qui fait passer le score de Mallampati à III–IV. Finalement, avec l’amélioration du tracé foetal, on accouche la patiente par voie vaginale sous infiltration locale. Au postpartum, le Mallampati est toujours à III–IV Cependant, 12 heures plus tard, on constate que le score de Mallampati redevient I–II comme à l’admission. Nous recommandons de toujours réévaluer l’airway d’une parturiente avant l’induction de l’anesthésie générale, même si cet examen a déjà été fait à l’admission.

The effects of maternal position during induction of combined spinal-epidural anesthesia for cesarean delivery.

Combined spinal-epidural anesthesia (CSE) is a popular technique for cesarean delivery. Regional blocks in obstetrics are often performed with the parturient in the sitting position because the midline may be recognized more easily than in the lateral decubitus position. When conventional spinal anesthesia is performed in the sitting position, the patient is placed supine immediately after drug injection. In contrast, when CSE is performed with the woman sitting, there is a delay in assuming the supine position because of epidural catheter placement, which may affect the incidence of hypotension. Healthy women, at term of pregnancy, about to undergo an elective cesarean section under CSE, were randomly assigned to the sitting or lateral recumbent position for initiation of the block. All parturients were given 1000 mL of lactated Ringers solution in the 15 min preceding induction and an additional 300-500 mL while the actual block was being performed. On completion of the CSE, they were turned to the supine position with left uterine displacement. A second anesthesiologist, blinded to the womans position during CSE, evaluated the sensory level of anesthesia, maternal heart rate, blood pressure, oxygen saturation, need for ephedrine, and occurrence of nausea and vomiting. Results are expressed as mean +/- SD. Twelve women were studied in the sitting group and 10 were studied in the lateral recumbent group. The severity and duration of hypotension were greater in those parturients who had CSE induced in the sitting (47% +/- 7% and 6 +/- 3 min, respectively) compared with the lateral recumbent position (32% +/- 14% and 3 +/- 2 min, respectively). Women in the sitting group also required twice as much ephedrine (38 +/- 18 mg) to correct hypotension compared with the other group (17 +/- 12 mg). In conclusion, the severity and duration of hypotension were greater when CSE was induced in the sitting compared with the lateral decubitus position. Implications: We studied the induction of combined spinal-epidural anesthesia (CSE) in the sitting versus lateral recumbent positions in healthy women undergoing a scheduled cesarean delivery. The severity and duration of hypotension were greater when CSE was induced in the sitting position. Thus, the position used for induction of CSE should be among the factors considered when there is greater maternal or fetal risk from hypotension. (Anesth Analg 1998;87:614-8)

Neonatal Neurobehavioral Tests Following Vaginal Delivery Under Ketamine, Thiopental, and Extradural Anesthesia

Scanlons neurobehavioral tests were administered to 274 neonates on the 1st and 2nd days of life. Ketamine-N2O anesthesia had been given to 45 mothers, thiopental-N2O to 52, and lumbar extradural anesthesia with chloroprocaine to 177. All babies delivered from mothers receiving meperidine within 5 hours of delivery were excluded. All babies tested were over 2500 grams in weight, apparently normal, and with Apgar scores of at least 8 at 1 minute and 10 at 5 minutes. All were delivered from healthy women aged 18 to 35 years following a normal labor.Lumbar extradural anesthesia was associated with the greatest percentage of high scores on both the 1st and 2nd days for overall assessment, tone, rooting, sucking, Moros response, placing, alertness, and habituation to pinprick. The scores were lowest after thiopental and intermediate following ketamine. No relationship was found between neurobehavior and low-forceps extraction, oxytocin augmentation, parity, or duration of labor.

Pharyngolaryngeal Edema as a Presenting Symptom in Preeclampsia

Pharyngolaryngeal edema, a rare and serious complication of obstetric anesthesia, was associated with preeclampsia in four of seven reported cases. The authors treated two severely preeeclamptic women with this complication who required general anesthesia for cesarean section. In both women, gentle direct laryngoscopy under topical anesthesia of the oropharynx was undertaken to detect possible difficulty in endotracheal intubation. Based on the findings at laryngoscopy, one patient was intubated while awake and breathing spontaneously. The other patient could be managed safely in the usual manner. Postoperatively, both women were nursed in an intensive care unit until after the airway problem had subsided.

Neonatal neurobehavioral tests following cesarean section under general and spinal anesthesia

The Scanlon Group of Early Neonatal Neurobehavioral Tests (E.N.N.S.) was administered to 150 babies delivered by elective cesarean section. Fifty of the mothers were induced into general anesthesia with thiopental, 4 mg. per kilogram, and 50 with ketamine, 1 mg. per kilogram. Fifty mothers received spinal anesthesia with 6 to 8 mg. of tetracaine. All mothers receiving spinal anesthesia were given 100 per cent oxygen by a transparent face mask and all undergoing general anesthesia received N2O-O2 (6L:6L) until delivery of the baby. All mothers were healthy and all babies weighed 2,500 grams or more, were apparently normal, and had Apgar scores of 7 or more at one minute to 10 at five minutes. Spinal anesthesia was associated with the greatest percentage of high scores on both the first and second day for overall assessment, pinprick response, tone, rooting, sucking. Moro response, placing, alertness, and total decrement (habituation) scores. There was a statistically significant difference between all the scores for spinal compared to the other two groups. The scores were lowest following a thiopental induction and intermediate with ketamine although the difference did not reach statistical significance.

Maternal lactate, pyruvate, and excess lactate production during labor and delivery☆☆☆

Abstract Blood lactate and pyruvate studies in healthy parturient patients disclosed a steady rise in both the aerobic and anaerobic carbohydrate metabolism during the course of labor. Peak levels of lactate, pyruvate, and excess lactate were reached at the time of parturition. A slow progressive decline of the three metabolites occurred in the early postpartum period. A major part of the excess lactate accumulated during labor and delivery appeared to be formed in the uterus caused by a lack of molecular oxygen at the local tissue level. It is postulated that this local tissue hypoxia provides the rational for the efficacy of “prophylactic” oxygen.