Effect of stimulation of the P6 antiemetic point on postoperative nausea and vomiting.

The antiemetic action of stimulation of the P6 (Neiguan) acupuncture (ACP) point has been studied in women, premedicated with nalbuphine 10 mg, undergoing minor gynaecological operations under methohexitone-nitrous oxide-oxygen anaesthesia. Invasive ACP--manual or electrical at 10 Hz--applied for 5 min at the time of administration of the premedication markedly reduced the incidence of vomiting and nausea in the first 6 h after operation, compared with untreated controls. This did not occur with stimulation of a "dummy" ACP point outside the recognized ACP meridians. Non-invasive methods (stimulation via a conducting stud or by pressure) were equally as effective as invasive ACP during the early postoperative period. However, both these non-invasive approaches were less effective than invasive ACP in the 1-6 h postoperative period, although each was as effective as two standard antiemetics (cyclizine 50 mg, metoclopramide 10 mg). In view of the total absence of any side effects in more than 500 ACP procedures, the clinical applications of this finding are worthy of further study.

Acupuncture prophylaxis of cancer chemotherapy-induced sickness.

In a multi-facet study we evaluated the efficacy of P6 electroacupuncture (10 Hz applied for 5 min) as an antiemetic in patients receiving a variety of cancer chemotherapy drugs. The study involved 130 (15 in an open pilot study, 10 in a randomized placebo controlled crossover study and 105 in a definitive study) patients who had a history of distressing sickness after previous treatment, and who, on the basis of a previous survey, would be expected to have a 96% chance of this with subsequent therapy. Sickness was either completely absent or reduced considerably in 97% of patients and no side effects were encountered. The limited crossover study, using a 'dummy' acupuncture (ACP) point showed that the beneficial effects were limited to the P6 point. Logistic and ethical considerations excluded the possibility of carrying out a larger placebo-controlled study. While in our hands P6 ACP was an effective antiemetic in patients having cancer chemotherapy, because of the time involved and the brevity of the action (8 h) an alternative approach to electro-ACP is required before this technique is adopted clinically.

Physical characteristics of large-volume low-pressure cuffed endotracheal tubes.

This study compares some physical characteristics of a selection of cuffed endotracheal tubes with large-volume, low-pressure cuffs currently used in the United Kingdom. Six types of endotracheal tubes of Sizes 7, 8 and 9 were studied. There was considerable variation in physical characteristics of endotracheal tubes and cuffs from different manufacturers and even from the same manufacturer.

P6 acupressure reduces morning sickness.

A prospective study was designed to test the efficacy of pressure at the P6 (Neiguan) acupuncture point, in preventing morning sickness. Three groups of patients in early pregnancy recorded the severity and frequency of sickness over a period of 4 consecutive days following daily pressure at P6 point, pressure at a point near the right elbow and with no treatment. Troublesome sickness was significantly less in both the genuine (23/119) and dummy (41/112) pressure groups as compared with the control series (67/119). When the data are adversely 'weighted' to compensate for the lower incidence of fully completed returns in the active treatment groups, only the P6 group show a significant reduction in sickness. No side effects occurred in either group and while anticipation of benefit may offer a partial explanation for the findings, pressure at the Neiguan point appears to have a specific therapeutic effect.

Plasma concentrations of bupivacaine during extradural anaesthesia for caesarean section. The effect of adrenaline.

The clinical effects and plasma levels associated with the use of 0.5% bupivacaine with and without the addition of 1:200,000 adrenaline (5 micrograms/ml) were studied in 30 patients who underwent extradural anaesthesia for elective Caesarean section. The addition of adrenaline to bupivacaine prolongs analgesia, reduces the degree of hypotension and delays its onset. Plasma bupivacaine levels were consistently lower when adrenaline was added, but this difference was significant only at 10 minutes after the initial dose. Prolonging the interval between increments seems to be a more reliable way to reduce plasma concentration than the addition of the catecholamine.

Isoflurane as an alternative to halothane for caesarean section.

Two series of 25 patients who underwent elective Caesarean section with general anaesthesia were given either 0.75% isoflurane or 0.5% halothane as supplements to 50% nitrous oxide in oxygen used for maintenance. The potent inhalational agent was given for the entire operative period and no case of intra-operative dreaming or awareness was reported. The infusion dose of suxamethonium was significantly less with isoflurane, 50 micrograms/kg/minute (SD 17), as compared to halothane, 64 micrograms/kg/minute (SD 24) (p less than 0.02). Recovery from anaesthesia was more rapid with isoflurane. The surgeon's assessment of uterine relaxation and bleeding using a visual analogue score indicated that this was significantly less with isoflurane. Infant well-being as judged by Apgar score and cord blood gas analysis, showed little difference between the two inhalational agents.

Antiemetic studies with traditional Chinese acupuncture. A comparison of manual needling with electrical stimulation and commonly used antiemetics.

The application of low frequency (10 Hz) electrical current for 5 minutes to an acupuncture needle placed at the P6 (Neiguan) point is as effective as manual needling in the reduction of emetic sequelae in women premedicated with nalbuphine 10 mg for a minor gynaecological operation carried out under a standard anaesthetic. Both were slightly, but not significantly, better than the antiemetic properties of cyclizine 50 mg.

Traditional Chinese acupuncture: a potentially useful antiemetic?

Two consecutive studies were undertaken to evaluate the effectiveness of acupuncture as an antiemetic used in addition to premedication with opioids in patients undergoing minor gynaecological operations. In the first study 25 of the 50 patients underwent acupuncture immediately after premedication with 100 mg meptazinol, the rest receiving the drug alone, and in the second 75 patients were allocated randomly to one of three groups: a group receiving 10 mg nalbuphine and acupuncture, a group receiving premedication and dummy acupuncture, and a group receiving premedication alone. Manual needling for five minutes at the P6 acupuncture point (Neiguan) resulted in a significant reduction in perioperative nausea and vomiting in the 50 patients who underwent acupuncture compared with the 75 patients who received no acupuncture. These findings cannot be explained, but it is recommended that the use of acupuncture as an antiemetic should be explored further.