J.T. Davidson

EPIDURAL MORPHINE IN TREATMENT OF PAIN

Epidural injections of a 2 mg morphine were given to 10 patients with severe acute or chronic pain. All cases had considerable amelioration of pain, which commenced within 2-3 min, reached a peak in 10-15 min, and was effective for 6-24 h. It is suggested that the morphine reached the subarachnoid space and produced its effect by direct action on the specific opiate receptors in the substantia gelatinosa of the posterior-horn cells of the spinal cord.

High frequency positive pressure ventilation during general anesthesia for extracorporeal shock wave lithotripsy.

Extracorporeal shock wave lithotripsy (ESWL), a noninvasive treatment for renal calculi, achieves contactfree destruction of urinary stones through extracorporeally generated shock waves (1,2). The patient undergoing ESWL requires anesthesia, mainly because the shock waves (up to 2000 per treatment) are very painful. Also, accurate placement of the focus of maximal energy of the shock waves on the stone is vital for a successful procedure, and movement may displace the stone from that focus, leading to unnecessary trauma to adjacent organs, as well as partial or no disintegration of the stone itself. Both general and regional anesthesia are being used for ESWL (1,3). However, during either spontaneous or conventional mechanical ventilation, the diaphragmatic movements drive the stone up and down along a vertical axis, causing a proportion of the shock waves to miss the stone altogether. This suggested the use of high frequency jet ventilation (HFJV) at a rate of 100-300 breathdmin as the preferred mode of ventilation during anesthesia for ESWL (4,5), because the stone remains virtually stationary due to the low tidal volumes used in HFJV (4,6,7). However, most anesthesiologists would be hesitant to use HFJV during ESWL, because this is still an unconventional and somewhat unpredictable ventilatory mode. Moreover, in most places special HFJV ventilators would have to be purchased and used for the first time. We have thus employed a conventional anesthesia ventilator for the delivery of high-frequency positive pressure ventilation (HFPPV) during anesthesia for ESWL. A ventilatory rate of 80 breathdmin with a tidal volume of approximately 3

Spinal narcotics and central nervous system depression

A case of central nervous system depression which developed 7 hours after an intrathecal injection of 4 mg of morphine is described. The patient lapsed into coma with bradypnoea and ‘pin‐point’ pupils and there was no response to naloxone 0·4 mg. Treatment was continued for 3 hours. No postoperative analgesics were required for 126 hours. The problems associated with the use of intrathecal opiates are reviewed, delay in onset being the usual feature. Use of hyperbaric solutions of the narcotic and maintenance of a head‐up posture may protect against respiratory depression.

BACK PAIN after epidural analgesia

OSMPERATIVE back pain is a well-known P complication of epidural analgesia. According to Wylie and Churchill-Davidson,l it is the most common sequela of the procedure. It occurred in 3 per cent of the cases studied by Foldes and associates,2 who claim it to be the only complication more common after epidural than after spinal analgesia. In a series of over 3500 cases reviewed by Bonica and coworkers,3 the incidence of postoperative back pain was 2.41 per cent, while Lund and associates4 found an incidence of about 2 per cent.

Epidural Anaesthesia and Bed Rest in Sciatica

Isle of Wight, an area where Skone2 found that 6.3% of churn samples from 520 registered dairy herds were infected with Brlcella. The disease may not come to notice until many months or even years later, when the holiday milk supply has been long forgotten. Therefore in obscure cases of fever, arthritis, depression, lassitude, etc., it may be worth inquiring carefully into past holidays.-I am, etc.,