Robert Hodgkinson

Systemic and pulmonary blood pressure during caesarean section in parturients with gestational hypertension.

Twenty severely pre-eclamptic patients requiring caesarean section for delivery were allocated to two groups. One group received epidural anaesthesia consisting of either 20 ml of bupivacaine 0.75 per cent at L3-4 or 12ml at Ll-2. The other group received general anaesthesia consisting of thiopentone, 40 per cent nitrous oxide and halothane 0.5 per cent. Mean arterial pressure (MAP), pulmonary artery pressure (PAP), pulmonary wedge pressure (PWP), and central venous pressure (CVP) were recorded at five-minute intervals for at least 60 minutes before operation and at least every two minutes during anaesthesia. Patients receiving general anaesthesia had pressures recorded every minute during tracheal intubation and extubation. There was a mean increase of MAP of 45 mm Hg, of PAP 20 mm Hg, and PWP 20mm Hg during intubation and extubation. Apart from a slight mean fall in MAP the parturients receiving epidural anaesthesia showed little change in these cardiovascular parameters.It is concluded that tracheal intubation of patients with gestational hypertension produces an increase in MAP, PAP, and PWP which can lead to a significant risk of cerebral haemorrhage and pulmonary oedema. The value and dangers of using short-acting hypotensive agents to prevent these episodes of hypertension has still to be assessed. With epidural anaesthesia there is a danger of hypotension which can be treated with intravenous fluid replacement and ephedrine.RésuméVingt patients en pré-éclampsie grave ont été divisées au hasard en deux groupes avant ľaccouchement par césarienne. Celles du premier groupe ont été opérées sous péridurale (20 ml de bupivacaïne à 0.75 pour cent injectés à L3 L4 ou 12 ml du même agent à L1, L2). Une anesthésie générale (thiopental, protoxyde ďazote à 40 pour cent et halothane à 0.5 pour cent) a été administrée aux patients du second groupe. La pression artérielle moyenne, la pression de ľartère pulmonaire, la pression capillaire bloquée et la pression veineuse centrale, ont été enregistrées aux cinq minutes durant au moins une heure avant ľintervention et au moins aux deux minutes durant ľanesthésie. On a effectué les mesures aux minutes au cours de ľintubation et de ľextubation chez les patientes soumises à une anesthésie générale. Au cours de ľintubation et de ľextubation, on a observé des élévations moyennes de 5.99 kPa (45 mm Hg) de la pression systémique moyenne et de 2.66 kPa (20 mm Hg) dans les cas de la pression de ľartère pulmonaire et de la pression capillaire bloquée. On n’a observé qu’une légère diminution de la pression systémique moyenne chez les patientes opérées sous péridurale.Donc, on retiendra que ľintubation trachéale chez les malades présentant une hypertension gravidique produit une élévation des pressions systémiques moyenne, pulmonaires et capillaires, avec un risque significatif ďhémorragie cérébrale et ďœdème aigu du poumon. Les avantages et les dangers liés à ľusage ďhypotenseurs ďaction courte restent à évaleur chez ces malades. Un dangerďhypotension existe avec ľanesthésie péridurale, hypotension qui se traite avec une charge liquidienne et ľéphédrine.

Double-blind comparison of the neurobehaviour of neonates following the administration of different doses of meperidine to the mother.

SummaryThe Early Neonatal Neurobehavioural Scale (E.N.N.S.) tests, first described by Scanlon,et al.1 were administered to 920 neonates on the first and second days of life. Meperidine was not given to 389 mothers, 50 mg was given to 358 mothers and 75 to 150 mg to 173 mothers within four hours of delivery. The delivery was conducted under chloroprocaine epidural anaesthesia in 280, ketamine-nitrous oxide general anaesthesia in 180, thiopentone-nitrous oxide general anaesthesia in 180 and lidocaine pudendal block in 280. All babies were over 2500 grams in weight with an Apgar score of at least 8 at one minute and 10 at five minutes. All were delivered from healthy women 18 to 35 years of age following a normal labour. The evaluator was unaware of the anaesthetic management, the method of delivery or the perinatal risk factors. There was no significant difference between the mothers and babies in the three meperidine dosage groups for maternal parity, maternal age, birth weight, number of forceps deliveries or duration of labour.Administration of meperidine was associated with a broad spectrum depression of most items on the E.N.N.S. on both the first and second days of life. The depression was greatest with the highest dose of meperidine. The depression produced by anaesthetic agents and meperidine were additive and the highest scores on this scale were obtained in those babies delivered under chloroprocaine epidural anaesthesia without meperidine.RésuméCes dernières années, la dépression produite par les narcotiques, les neuroleptiques et les agents anesthésiques sur la système nerveux central du nouveau-né n’a été mesurée que par ľindice ďApgar. Cette baisse du résultat de ľ Apgar causée par des médicaments malgré la stimulation intense de la naissance signifiait que la dose était trop forte, le bébé susceptible de façon exagérée ou que la dose était administrée trop près de ľaccouchement. Les limites inhérentes à ľindice ďApgar ont été reconnues par Apgar elle-même qui écrivait que ľindice ne pouvait se substituer à un examen physique minutieux ou à ľobservation répétée lors des premières heurs de la vie. Avec les travaux de Prechtl et Beintema, Brazelton, et Scanlon, sont apparus plusieurs test du neuro-comportement du nouveau-né, tests qui peuvent être répétés pendant la péiode néonatale.Les auteurs ont évalué le neuro-comportement précoce de 920 nouveaux-nés en utilisant ľéchelle établie par Scanlon et ses collaborateurs à la première et à la deuxième journée de la vie. Un groupe de 389 mères n’avait pas reçu de mépéridine, alors que 358 en avaient reçu 50 mg, 173 de 75 mg à 110 mg dans les quatre heures précédant ľaccouchement. Ľaccouchement fut effectué sous anesthésie péridurale à la chloprocaine dans 280 cas, sous kétamine associée au protoxyde ďazote dans 180 et sous bloc honteux dans 280 cas. Tous les bébés pesaient plus de 2500 g et avaient un Apgar ďau moins huit à la première minute et de dix à la cinquième minute. Toutes les mères étaient en bonne santé, étaient âgées de 18 à 35 ans et connurent un accouchement normal. Ľévaluateur ne connaissait ni ľanesthésie utilisée, ni le mode ďaccouchement, ni les facteurs de risque de la période péri-natale. Il n’y eut aucune différence significative pour les trois groupes déterminés par la dose de mépéridine en ce qui concerne la parité, ľâge de la mère, le poids du bébé à la naissance et ľincidence ďapplications de forceps ou la durée du travail.Un abaissement général de tous les paramètres du test de Scanlon fut associé à ľadministration de mépéridine pour tous les bébés au premier et au deuxième jour de vie. Cet abaissement fut plus marqué pour la dose la plus élevée de mépéridine. Il fut noté que ľaddition ďagents anesthésiques à la mépéridine aggravait cette dépression et que les meilleurs résultats sur ľéchelle de Scanlon étaient obtenus lors ďanesthésie péridurale à la chloprocaine sans mépéridine.

Comparison of Cimetidine (Tagamet®) with Antacid for Safety and Effectiveness in Reducing Gastric Acidity before Elective Cesarean Section

One hundred twenty-six parturients for elective cesarean section under general anesthesia were allocated to either a cimetidine or an antacid group in a randomized, double-blind, multicenter trial. The cimetidine-treated group received 300 mg cimetidine orally the evening before the operation and 300 mg intramuscularly between 1 and 3 h preoperatively. The antacid-treated group received 30 ml of Mylanta-II orally on both occasions. Gastric volume, 30 min after induction of anesthesia and 30 min before response to oral commands, was less in the cimetidine-treated group. Gastric pH 30 min after induction was greater in the cimetidine-treated group. The maternal serum level of cimetidine at birth was 1.31 +/- 0.12 micrograms/ml and the umbilical venous level was 0.78 +/- 0.05 micrograms/ml. The neonatal gastric acidity, Apgar scores, and Early Neonatal Neurobehavioral Scale (ENNS) scores were similar in both groups. No maternal or neonatal complication was attributed to treatment.

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.

Obesity, gravity, and spread of epidural anesthesia.

Epidural anesthesia was administered for cesarean section in 250 parturients using 20 ml of 0.75% bupivacaine administered at L3–4 with the patient in a sitting position for 5 minutes. Comparing the results with those obtained in a previous study in which parturients were kept horizontal at all times, it was found that the sitting position limited cephalad spread of anesthesia only in obese patients and that the decrease in spread was in proportion to the degree of obesity. The previous findings that cephalad spread is positively correlated to body mass index BMI (weight in kilograms divided by height in meters squared) and with body weight were confirmed.

Neonatal gastric pH.

The pH of gastric juice, obtained 3 to 4 minutes after birth in 158 unselected neonates, varied between 7.5 and 8.5 in 8 meconium-containing specimens and ranged from 1.4 to 7.8 in 150 meconium-free samples. In mature infants of the latter group, pH was (1) significantly lower after vaginal delivery than after cesarean section; (2) tended to be lower after section preceded by labor than after elective section; and (3) was lowest after precipitate delivery. In premature infants, pH was above 7 regardless of mode of delivery.There was no correlation between neonatal gastric pH and pH of simultaneously obtained maternal gastric juice, pH of amniotic fluid, pH of cord blood, duration of rupture of membranes, birth weight, or Apgar score. It was concluded that the mature human fetus produces gastric acidity in response to stresses associated with labor and vaginal delivery.The possibility of a low gastric pH and the resultant pulmonary damage if aspirated must be considered in the initial care of the newborn with poor muscle tone or reflex activity as well as in the anesthetic management of neonates undergoing emergency surgery.

Double-blind comparison of maternal analgesia and neonatal neurobehaviour following intravenous butorphanol and meperidine.

Butorphanol (1 mg and 2 mg) and meperidine (40 mg and 80 mg), given intravenously, were evaluated for analgesic efficacy and safety in a double-blind randomized study employing 200 consenting pre-partum patients in moderate to severe pain during the late first stage of labour. Both drugs provided adequate relief of pain to the mothers. There was no significant difference in the rate of cervical dilation, the foetal heart rate, the Apgar score, pain relief or neonatal neurobehavioural scores between those receiving butorphanol and those receiving meperidine. Twenty-two mothers who received butorphanol and eleven who received meperidine nursed their infants with no adverse effects observed. Side-effects were generally infrequent in this study; however, more side-effects were reported by the patients and observed by the investigator in the meperidine-treated cases (13%) than in the cases treated with butorphanol (2%).

Comparison of Cimetidine (Tagamet??) With Antacid for Safety and Effectiveness in Reducing Gastric Acidity Before Elective Cesarean Section

One hundred twenty-six parturients for elective cesarean section under general anesthesia were allocated to either a cimetidine or an antacid group in a randomized, double-blind, multicenter trial. The cimetidine-treated group received 300 mg cimetidine orally the evening before the operation and 300 mg intramuscularly between 1 and 3 h preoperatively. The antacid-treated group received 30 ml of Mylanta-II® orally on both occasions. Gastric volume, 30 min after induction of anesthesia and 30 min before response to oral commands, was less in the cimetidine-treated group. Gastric pH 30 min after induction was greater in the cimetidine-treated group. The maternal serum level of cimetidine at birth was 1.31 ± 0.12 μg/ml and the umbilical venous level was 0.78 ± 0.05 μg/ml. The neonatal gastric acidity, Apgar scores, and Early Neonatal Neuro-behavioral Scale (ENNS) scores were similar in both groups. No maternal or neonatal complication was attributed to treatment.

Neonatal Neurobehavior in the First 48 Hours of Life: Effect of the Administration of Meperidine with and without Naloxone in the Mother

The early neonatal neurobehavioral scale was administered to three groups of newborns at 2, 4, and 24 hours of age. Group 1 consisted of 28 babies whose mothers had received no narcotics during labor, group 2 of 33 babies whose mothers had received meperidine hydrochloride alone during labor, and group 3 of 40 babies whose mothers had received meperidine followed by 0.4 mg of naloxone hydrochloride intravenously approximately 15 minutes before delivery. Babies who were not exposed to meperidine showed a statistically significantly greater percentage of high scores than those exposed to meperidine alone for all items on the neurobehavioral scale at 2 and 4 hours and for all items except tone and Moro response at 24 hours. Similarly, babies whose mothers had received meperidine and naloxone showed a significantly greater percentage of high scores than those whose mothers had received meperidine alone at 2 hours of age. At 4 hours a difference was found for tone and rooting and at 24 hours for overall score, placing, and total decrement score. It is concluded that naloxone given intravenously to the mother reverses the effect of meperidine on neonatal neurobehavior for approximately two hours after birth. At 4 and 24 hours, however, the neurobehavior of neonates exposed to meperidine and naloxone is depressed almost as much as that of babies exposed to meperidine alone.

Double-Blind Comparison of the Neurobehaviour of Neonates Following Administration of Different Doses of Meperidine to the Mother

The Early Neonatal Neurobehavioural Scale (E.N.N.S.) tests, first described by Scanlon, et al.1 were administered to 920 neonates on the first and second days of life. Meperidine was not given to 389 mothers, 50 mg was given to 358 mothers and 75 to 150 mg to 173 mothers within four hours of delivery. The delivery was conducted under chloroprocaine epidural anaesthesia in 280, ketamine-nitrous oxide general anaesthesia in 180, thiopentone-nitrous oxide general anaesthesia in 180 and lidocaine pudendal block in 280. All babies were over 2500 grams in weight with an Apgar score of at least 8 at one minute and 10 at five minutes. All were delivered from healthy women 18 to 35 years of age following a normal labour. The evaluator was unaware of the anaesthetic management, the method of delivery or the perinatal risk factors. There was no significant difference between the mothers and babies in the three meperidine dosage groups for maternal parity, maternal age, birth weight, number of forceps deliveries or duration of labour. Administration of meperidine was associated with a broad spectrum depression of most items on the E.N.N.S. on both the first and second days of life. The depression was greatest with the highest dose of meperidine. The depression produced by anaesthetic agents and meperidine were additive and the highest scores on this scale were obtained in those babies delivered under chloroprocaine epidural anaesthesia without meperidine.