Neither epidural (EDA) or intrathecal (IT) morphine nor EDA opiate + bupivacaine provides acceptable relief of some types of cancer pain, e.g. pain originating from mucocutaneous ulcers, deafferentation pain, continuous and intermittent visceral and ischaemic pain, and that occurring with body movement as a result of a fracture. To improve pain relief in such conditions, we gave combinations of morphine and bupivacaine through open IT-catheters to 52 patients with "refractory", severe (VAS 7-10 out of 10), complex cancer pain (Edmonton Stage-3), for periods of 1-305 (median = 23) days. The efficacy of the treatment was estimated from: 1) daily dosage (intraspinal and total opiates, and intraspinal bupivacaine), and 2) scores of non-opiate analgesic and sedative consumption, gait and daily activities, and amount and pattern of sleep. Forty-four patients obtained continuous and acceptable pain relief (VAS 0-2), 26 of them with daily doses of IT-bupivacaine of less than or equal to 30 mg/day (less than or equal to 1.5 mg/h). Higher IT-bupivacaine doses (greater than 60-305 mg/day), not always giving acceptable pain relief, were necessary in 13 patients with deafferentation pain from the spinal cord or brachial or lumbosacral plexuses or pain from the coeliac plexus, or from large, ulcerated mucocutaneous tumours. By combining IT-bupivacaine with IT-morphine, it was possible to use relatively low IT-morphine doses (10-25 mg/day during the first 2 months of treatment) in more than half of the patients. The IT-treatment significantly decreased the total (all routes) opiate consumption and significantly improved sleep, gait and daily activities. For the whole period of observation (6 months), the IT-treatment was assessed as adequate in 3.8%, good in 23.1%, very good in 59.6% and excellent in 13.5% of the cases. Adverse effects of the IT-bupivacaine (paraesthesiae, paresis, gait impairment, urinary retention, anal sphincter disturbances and orthostatic hypotension) did not occur with doses of 2.5-3.0 mg/h (approx. 60-70 mg/day).

SummaryHypoxaemia may occur afier hyperventilation with nitrous oxide during labour. The purpose of this study was to .assess whether diffusion hypoxia is a contributory factor. Twenty-four parturients were randomly allocated to receive 50 or 70% nitrous oxide in oxygen. The median nitrous oxide inhalation time per contraction was 58 s and 33 s, respectively. The end-tidal carbon dioxide and the minute ventilation remained unchanged. The end-tidal oxygen concentration was lowest at 120s, reaching 15.4% in both groups. The oxygen saturation did not diger between the groups with a lowest median value of 96% before the start of nitrous oxide inhalation. Two parturients had episodes of desaturation. Both had low end-tidal oxygen concentrations in association with the desaturation but, as the end-tidal nitrous oxide concentrations were low, the desaturations could not be attributed to digusion hypoxia.

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Decreased respiratory depression during emergence from anesthesia with sevoflurane/N20 than with sevoflurane alone Purpose: To investigate ventilation and gas elimination during the emergence from inhalational anesthesia with controlled normoventilation with either sevoflurane/N20 or sevoflurane alone. Methods: Twenty-four ASA I-II patients scheduled for abdominal hysterectomy were randomly allocated to receive either 1.3 MAC sevoflurane/N20 (n= 12) or equi-MAC sevoflurane (n= 12) in 30% oxygen (02). Expired minute ventilation volumes (VE), end-tidal (ET) concentrations of 02, carbon dioxide (CO2), sevoflurane and N20 as well as pulse oximetry saturation (SpO2) and CO 2 elimination rates (VCO2) were measured. The ET concentrations of sevoflurane and N20 were converted to total MAC values and gas elimination was expressed in terms of MAC reduction. Time to resumption of spontaneous breathing and extubation were recorded and arterial blood gas analysis was performed at the end of controlled normoventilation and at the beginning of spontaneous breathing. Results: Resumption of spontaneous breathing and extubation were 8 and 13 min less, respectively, in the sevoflurane/NzO than in the sevoflurane group. Spontaneous breathing was resumed in both groups when pH had decre .ased by 0.07-0.08 and PaCO 2 increased by 1.3-1.5 kPa. Depression of V E and VCO 2 were less, and MAC reduction more rap~d ~n the sevoflurane/N20 than ~n the sevoflurane group. Condu,sions: Respiratory recovery was faster after sevoflurane/N20 than sevoflurane anesthesia. Changes in pH and PaCO~ rather than absolute values were important for resumption of spontaneous breathing after controlled normoventdation. In both groups, the tracheas were extubated at about 0.2 MAC.Objectif: Observer la ventilation et 1'61imination des gaz pendant la r&up&ation de I'anesth6sie par inhalation avec une normoventilation contr61&, en utilisant un m~lange de s6voflurane/N20 ou seulement du s6voflurane. M6thode : Vingt-quatre patientes ASA I-II, dont I'hyst&ectomie abdominale ~tait pr~vue, ont 6t~ r~parties au hasard pour recevoir soit 1,3 CAM de s6voflurane/N20 (n = 12) ou la CAM 6quivalente de s6voflurane (n --12) dans 30 % d'oxyg~ne (02). On a pris les mesures suivantes : volumes expir& de ventilation-minute (VE), concentrations d'O 2 de fin d'expiration, gaz carbonique (CO2), s6voflurane et N20, saturation en oxyg~ne par oxym&rie puls& (SpO2) et vitesses d'61imination du CO 2 (VCO2). Les concentrations de s6voflurane et de N20 de fin d'expiration ont 6t6 transform&s en valeurs de CAM totales et 1'61imination des gaz a &6 exprim& en termes de r~duction de CAM. Le temps n&essaire au retour de la respiration spontan& et ~ I'extubation a ~t6 not6, I'analyse des gaz du sang art~del a ~t~ r6alis~e ~ la fin de la normoventilation contr61& et au d6but de la respiration spontan6e. R&-~ltats : Le retour de la respiration spontan6e et I'extubation ont demand~ 8 et 13 min de moins, respectivement, avec le s6voflurane/N20 qu'avec le s~voflurane seul. La reprise de la respirat...