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J A Crowhurst

Publications and source records attributed to J A Crowhurst.

At least 19 recordsLinked to original sources

The combined spinal-epidural technique.

Epidural and spinal blocks are well-accepted regional techniques, but they have several disadvantages. The CSE technique can reduce or eliminate the risks of these disadvantages. CSE block combines the rapidity, density, and reliability of the subarachnoid block with the flexibility of continuous epidural block to extend duration of analgesia. The CSE technique is used routinely at many institutions, particularly for major orthopedic surgery and in obstetrics. It has been used in tens of thousands of patients without any reports of major problems. Although at first sight the CSE technique appears to be more complicated than epidural or spinal block alone, intrathecal drug administration and siting of the epidural catheter are both enhanced by the combined, single-space, needle-through-needle method. Concerns about the epidural catheter entering the theca via the small puncture hole are now considered to be unfounded, but as with all epidural catheter techniques, vigilant monitoring of the patient during and after any injection is paramount. CSE is an effective way to reduce the total drug dosage required for anesthesia or analgesia. The intrathecal injection achieves rapid onset with minimal doses of local anesthetics and opioids, and the block can be prolonged with low-dose epidural maintenance administration. In addition, the sequential CSE method can be used to extend the dermatomal block with minimal additional drugs or even saline. Reduction in total drug dosage has made truly selective blockade possible. Many studies have confirmed that low-dose CSE with local anesthetic and opioid, or low-dose epidural block alone, will provide effective analgesia with minimal motor and proprioceptive block. Such neurologic selective blockade has made it possible for most patients to walk and bear down normally in labor or postoperatively. There remains concern about the risk of infection being increased when the CSE technique is used in place of epidural block alone. Despite a recent flurry of reports of meningitis with CSE procedures, there is no evidence the CSE block is more hazardous than epidural or subarachnoid block alone. Arguably, the single-space, needle-through-needle CSE technique will continue to improve with new needle designs and other advances to improve further the success rate and reduce complications, such as neurotrauma, PDPH, and infection. Over the past decade it has become clear that the CSE technique is a significant advance in regional blockade.

Analgesia, Epidural↗

Monitoring epidural analgesia in the parturient.

Appropriate monitoring during obstetric epidural analgesia consists of: 1. Indirect BP and pulse monitoring before epidural insertion, frequently after every dose, and intermittently thereafter. 2. The aspiration test before all injections. 3. Frequent clinical monitoring for signs of intravascular injection during administration of small intermittent doses (not more than 3-5 ml at a time). 4. Frequent clinical monitoring for sympathetic, sensory and motor signs indicating upward extension of the block. 5. Frequent monitoring of the fetal heart rate (FHR) and other signs of fetal welfare. In many instances continuous tocogram with fetal heart rate (CTG) monitoring is useful. We do not believe CTG use is mandatory for epidural analgesia in the uncomplicated pregnancy, but we do advocate that it (and other appropriate fetal monitoring techniques) be used when risk factors or complications, either fetal or maternal, are present or suspected. The anaesthetist should be familiar with fetal monitoring techniques, their use and interpretation. He or she should be prepared to recommend their use when it is considered appropriate to do so.

Analgesia, Epidural↗

Acid aspiration prophylaxis in Australian obstetric hospitals--a survey.

During 1987 a confidential survey of all hospitals in Australia providing obstetric services was undertaken to determine the antacid medications used routinely as prophylaxis against acid aspiration pneumonitis. Of the 567 hospitals surveyed, 379 (67%) responded. Of these, 243 hospitals provide an obstetric service which includes caesarean section, and 67% of these perform less than 500 deliveries per annum. Aspiration prophylaxis during labour was used in 22.4% of responding hospitals. Prior to elective caesarean section, 11.5% used no prophylaxis, and 39.4% used particulate antacids such as magnesium trisilicate mixture (33.3%) or Mylanta (6.1%). Sodium citrate mixture was the most popular therapy (37%). Results were similar in the emergency caesarean section group. The use of cimetidine or ranitidine was uncommon in all groups. Results of this survey suggest marked differences in attitudes towards acid aspiration prophylaxis between Australian and British obstetric anaesthetic practices.

Anesthesia, General↗