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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 12 ml at L1-2. 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 oede ma. 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 hypotcnsion which can be treated with intravenous fluid replacement and ephedrine.THERE ARE DISADVANTAGES to both general and regional anaesthesia for caesarean section in the parturient with gestational hypertension. Laryngoscopy and tracheal intubation of hypertensive patients, whether treated or not, produces greater increases in arterial blood pressure than in normotensive patients, t.: In pre-eclampsia this may be associated with increased sensitivity to angiotensin and norepinephrineP These excessive swings in arterial pressure are cause for concern since, in various studies on gestational hypertension 4,s,6 cerebral haemorrhage or oedema have been responsible for 29 to 53 per cent of deaths and cardiac failure for 10 to 29.5 per cent. The autopsy findings on 33 eclamptic patients 7 showed cerebral haemorrhage in 57.6 per cent, cerebral oedema in 18.2 per cent and cardiac hypertrophy in 78.8 per cent.

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. Three 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 thew newborn with poor muscle tone or reflex activity as well as in the anesthetic management of neonates undergoing emergency surgery.

Inspired by the natural locomotion of jellyfish and squid, a series of compact thrusters series is developed for propulsion and maneuvering of underwater vehicles. These thrusters successively ingest and expel jets of water in a controlled manner at high frequencies to generate propulsive forces. The parameters controlling the performance of the thrusters are reviewed and investigated to achieve higher thrust levels. The thrusters are compact and can be placed completely inside a vehicle hull providing the desired maneuvering capability without sacrificing a sleek hydrodynamic shape for efficient cruising. The system design of a prototype hybrid vehicle, called CephaloBot, utilizing these thrusters, is also presented. A compact and custom-developed embedded system is also designed for the CephaloBot. Key features of the system include a base set of navigational sensors, an acoustic system for localization and underwater communication, Xbee RF transceiver for communication above water, and a LabVIEW programmed processing board.

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