Nausea and vomiting with use of a patient-controlled analgesia system

Semi-Permanent Acupuncture Needles in the Prevention of Post-Operative Nausea and Vomiting

The efficacy of acupressure and acupuncture at the Pericardium 6 (PC.6) point in relieving post-operative nausea and vomiting (PONV) is well known. Lengthy manual stimulation of the needles, or electrostimulation, is inconvenient and incurs extra costs. The aim of this study was to test the effectiveness of the antiemetic action of semi-permanent acupuncture needles (SPANs), a cheap and convenient method of administering acupuncture, in the first 48 hours following gynaecological surgery.

Patients (n = 36) having total abdominal hysterectomy were studied in a randomised, placebo controlled trial. Study group patients had SPANs inserted in PC.6 on both wrists. The control group had SPANs inserted into sham points on their forearms. There was no difference in the median nausea scores between the groups; however six patients suffered moderate or severe nausea during the second 24 hours in the control group, with none in the study group (p < 0.05). In addition, the nausea score between 8 and 24 hours in patients who had previously experienced PONV, was lower in the study group (median score 2) compared to the control group (median score 4) (p < 0.05).

We conclude that the use of SPANs does not reduce the overall incidence of nausea and vomiting but does appear to reduce the severity of nausea in the second 24 hours, and has a greater effect on patients who had had nausea and vomiting after a previous anaesthetic.

The Effect of Pre-operative Lornoxicam and Ketoprofen Application on the Morphine Consumption of Post-operative Patient-controlled Analgesia

We compared the efficacy of preoperative intramuscular lornoxicam and ketoprofen for post-operative analgesia in patients undergoing abdominal hysterectomy. This randomized, double-blind, placebo-controlled, parallel-group study investigated 60 patients who received lornoxicam (group L, 8 mg), ketoprofen (group K, 100 mg) or saline (group C) 60 min before standard anaesthesia. All patients received patient-controlled analgesia (intravenous morphine) during the post-operative period. Visual analogue scale (VAS) scores recorded 2, 4, 6 and 12 h after surgery in groups L and K patients were significantly lower than in group C patients, and VAS scores at 2, 4 and 6 h in group L patients were significantly lower than those in group K patients. Morphine consumption in groups L and K was significantly lower than in group C. Pre-emptive administration of lornoxicam and ketoprofen effectively reduced post-operative pain and morphine consumption, and lornoxicam was more effective than ketoprofen in the early post-operative period.

Droperidol with patient-controlled analgesia

The addition of droperidol 5mg to the first 50ml of morphine 1mg/ml was compared with morphine alone in 60 patients receiving postoperative analgesia via a patient-controlled analgesia (PCA) system. All patients underwent an abdominal hysterectomy and had a standard anaesthetic which included 2.5mg of droperidol. They were followed up daily for three days postoperatively. The PCA with additional droperidol group received half the number of supplementary antiemetic doses (P&lt;0.05). There was no difference in the incidence of emetic sequelae or reported side effects. Prophylactic droperidol with PCA morphine reduces the need for further intramuscular antiemetic treatment.

Postoperative intravenous patient-controlled analgesia in thyroid surgery: comparison of fentanyl and ondansetron regimens with and without the nonsteriodal anti-inflammatory drug ketorolac

BACKGROUND

Nonsteroidal anti-inflammatory drugs (NSAIDs), through synergistic action with opioids, can reduce postoperative nausea and vomiting via intravenous patient-controlled analgesia (PCA). We compared the efficacy of three PCA regimens.

METHODS

Patients (n = 135) undergoing thyroidectomy were randomly allocated to three PCA regimens. All groups received 12 mg ondansetron (a serotonin 5-HT(3) receptor antagonist). In addition, Group I received the opioid fentanyl, 15 microg/kg. Group II received fentanyl 12.5 microg/kg and the NSAID ketorolac, 1.5 mg/kg, and Group III received fentanyl 10 microg/kg and ketorolac 3 mg/kg. Pain scores, nausea and vomiting, and dizziness were assessed 1, 6, 12, and 24 hours postoperatively.

RESULTS

Pain scores were similar among the three groups. However, postoperative nausea and vomiting was significantly lower in groups II and III (p < 0.05) than group I. Postoperative dizziness was significantly lower in group III than groups I and II (p < 0.05).

CONCLUSIONS

The NSAID ketorolac when combined with lower doses of the opioid fentanyl and the same dose of ondansetron is associated with the same analgesic efficacy but less nausea and vomiting after thyroid surgery. A higher ratio of NSAID to opioid, when used as reported here, is associated with less postoperative dizziness.

Prophylaxis of postoperative nausea and vomiting: controversies in the use of serotonin 5-hydroxytryptamine subtype 3 receptor antagonists

Postoperative nausea and vomiting (PONV) continues to be a "big little problem" despite recent advances in anesthesia. Because of an increased interest in, and the abundant publications on this topic, guidelines for the management of PONV were published in 2003. Several key but controversial issues regarding PONV prophylaxis were left unaddressed, however. These included whether clinical differences exist between the 5-hydroxytryptamine subtype 3 (5-HT3) receptor antagonists, concern over optimal dosage and timing of administration, optimal 5-HT3 receptor antagonist combination therapy, and whether rescue therapy is effective after prior administration of the same or a different 5-HT3 receptor antagonist. The application of these antiemetics in clinical practice has raised questions regarding the role of the 5-HT3 receptor antagonists in the treatment of postdischarge nausea and vomiting and opioid-induced nausea and vomiting. A brief overview of the incidence, risk factors and current management recommendations for PONV and current controversies with special emphasis on the 5-HT3 receptor antagonists, is discussed.

Tolerability of acute postoperative pain management: nausea, vomiting, sedation, pruritis, and urinary retention. Evidence from published data

This review examines the evidence from published data concerning the tolerability (indicated by the incidence of nausea, vomiting, sedation, pruritus, and urinary retention), of three analgesic techniques after major surgery; intramuscular analgesia (i.m.), patient-controlled analgesia (PCA), and epidural analgesia. A MEDLINE search of publications concerned with the management of postoperative pain and these indicators identified over 800 original papers and reviews. Of these, data were extracted from 183 studies relating to postoperative nausea and vomiting, 89 relating to sedation, 166 relating to pruritus, and 94 relating to urinary retention, giving pooled data which represent a total of more than 100,000 patients. The overall mean (95% CI) incidence of nausea was 25.2 (19.3-32.1)% and of emesis was 20.2 (17.5-23.2)% for all three analgesic techniques. PCA was associated with the highest incidence of nausea but the emesis was unaffected by analgesic technique. There was considerable variability in the criteria used for defining sedation. The overall mean for mild sedation was 23.9 (23-24.8)% and for excessive sedation was 2.6 (2.3-2.8)% for all three analgesic techniques (significantly lower with epidural analgesia). The overall mean incidence of pruritus was 14.7 (11.9-18.1)% for all three analgesic techniques (lowest with i.m. analgesia). Urinary retention occurred in 23.0 (17.3-29.9)% of patients (highest with epidural analgesia). The incidence of nausea and excessive sedation decreased over the period 1980-99, but the incidence of vomiting, pruritus, and urinary retention did not. From these published data it is possible to set standards of care after major surgery for nausea 25%, vomiting 20%, minor sedation 24%, excessive sedation 2.6%, pruritus 14.7%, and urinary retention requiring catheterization 23%. Acute Pain Services should aim for incidences less than this standard of care.

Antiemetic and analgesic-sparing effects of diphenhydramine added to morphine intravenous patient-controlled analgesia

BACKGROUND

This study was designed to examine the analgesic and dose-related antiemetic efficacy of diphenhydramine-morphine mixture for intravenous patient-controlled analgesia (PCA).

METHODS

Healthy women, undergoing abdominal total hysterectomy were recruited to this double-blinded randomized placebo-controlled study. Patients were randomly allocated to one of three groups (n=40 each). In group 1, patients received saline at induction and morphine 1 mg ml(-1) alone for postoperative PCA. Patients in groups 2 and 3 received diphenhydramine 30 mg i.v. at induction and were given a 1.2:1 or a 4.8:1 ratio, respectively, of diphenhydramine-morphine mixture for postoperative PCA.

RESULTS

A total of 112 patients completed the study. The incidence of postoperative nausea (31.6% vs 67.6%, P<0.01) and vomiting (15.8% vs 40.5%, <0.05) was significantly lower in group 3 than in group 1. Furthermore, the incidence of severe nausea was significantly lower in group 3 than in group 1 (2.6% vs 24.3%, P<0.05). The rescue antiemetic requirements were also significantly less in group 3 than in group 1 (5.3% vs 24.3%, P<0.05). However, there was no significant difference between group 2 and group 1 in any of the comparisons. Pain intensity, 24-h morphine consumption and diphenhydramine-related side-effects, such as sedation or dry mouth, did not differ among the three groups.

CONCLUSION

An initial bolus of diphenhydramine 30 mg at anaesthetic induction followed by postoperative PCA with a 4.8:1, but not 1.2:1, diphenhydramine-morphine mixture provides an effective antiemetic efficacy without morphine-sparing effects.

Does postoperative pain induce emesis?

OBJECTIVE

The aim of this prospective, controlled study was to evaluate the risk factors for postoperative emesis in patients undergoing gynecologic surgery and receiving patient-controlled analgesia for three days.

METHODS

Six hundred twenty-five gynecologic patients with an American Society of Anesthesiologists physical status of I to III undergoing lower-abdominal surgeries were enrolled. A standard, general anesthetic technique was used. Postoperative pain was treated by a patient-controlled analgesia device with bolus intravenous doses of 1 mg morphine. For 3 days after surgery patients were assessed for occurrence of emesis, sedation, and pain intensity when at rest and during movement.

RESULTS

The incidence of emesis was 26% on postoperative day 1, 13% on day 2, and 4% on day 3. On all 3 days, patients' pain scores when at rest and when coughing were higher for those with emesis than for those without. During the first 2 postoperative days the patients with and those without emesis consumed similar amounts of morphine daily, but on the third day the patients with emesis consumed significantly more morphine than did those without emesis ( <0.05). Further logistic regression analysis showed that incident pain was the main risk factor for postoperative emesis on all 3 days.

CONCLUSIONS

The results suggested that postoperative pain was an associative risk factor to increase the incidence of emesis in these female patients.

Patient-controlled analgesia and postoperative nausea and vomiting: efficacy of a continuous infusion of ondansetron

A continuous infusion of ondansetron was compared with a placebo infusion in 80 patients undergoing major breast reconstructive surgery. All patients received a standard anaesthetic and a bolus dose of ondansetron after induction. They were then randomly allocated to receive an intravenous infusion of ondansetron or a placebo infusion for 24 h in a double-blind fashion. Postoperative analgesia was provided by patient-controlled subcutaneous diamorphine. In the ondansetron group, the severity of nausea, measured by a 10-point verbal rating scale, was reduced (p = 0.01) and fewer patients stated at postoperative interview that nausea and vomiting was a problem (p = 0.01).

Morphine-sparing effect of ketoprofen after abdominal surgery

In a double-blind, placebo-controlled clinical trial (power of 80% to detect a 30% reduction in morphine consumption, P < 0.05), we have determined that the administration of two doses of intravenous ketoprofen 100 mg, one at the end of surgery and the second 12 hours postoperatively, was associated with a significant reduction in morphine consumption at eight (P = 0.028), 12 (P = 0.013) and 24 hours (P = 0.013) but not four hours (P = 0.065) postoperatively, as compared to placebo, when assessed by patient-controlled analgesia. There was no difference between the groups in pain scores or in the incidence of nausea and vomiting. One patient in the placebo group suffered from excessive sedation while one patient from the ketoprofen group suffered from transient oliguric renal failure. There were no other adverse effects. The results of this study show that ketoprofen does provide a morphine-sparing effect in the management of postoperative pain after abdominal surgery.

[Patient-controlled analgesia. Benefits, risks, methods of monitoring]

Patient-controlled analgesia refers to a relatively new approach to morphine delivery in which patients are allowed to self-administer small doses of an opioid, to achieve adequate relief of postoperative pain. The main benefit is to reduce fluctuations in opioid plasma concentrations. A matter for worry remains the occurrence of side effects, especially ventilatory depression. In order to guarantee the efficacy and safety of this technique, the education of patients and nurses is essential. Protocols are required, specifying the use of this technique (prescription, patient monitoring, treatment of side effects).

The safety and utilization of patient-controlled analgesia

Between December 1989 and March 1996, more than 6000 patients were treated with patient-controlled analgesia (PCA) at Auckland Hospital. The overall incidence of potentially life-threatening complications was low (0.28%). A small number (276) received PCA with a background opioid infusion. This technique was associated with a higher incidence of such complications (1.08%, P < 0.05). To further characterize the safety and utilization of PCA, a subgroup of 300 patients was analyzed. The average duration of PCA was 76.4 +/- 39.2 hr. The peak morphine consumption was highest on the day of operation (45.4 +/- 37.0 mg) and rapidly declined over the next 3 postoperative days (40.6 +/- 39.0, 33.3 +/- 26.2, and 27.8 +/- 36.6 mg, respectively). The ratio of drug demands to deliveries decreased from 1.76 on the morning of the first postoperative day to 1.17 on the evening of the third. The percentage of patients with inadequate analgesia (pain score > or = 3/10) and an inability to comply with physiotherapy (Bruggemann comfort score < or = 2/10) was high on the first postoperative day (42% and 18%, respectively). Men used significantly more morphine than women (141.7 +/- 123.6 versus 102.7 +/- 111.2 mg, P < 0.0001) and general surgical patients used more morphine than urology and orthopedic patients (152.6 +/- 136.9 versus 96.0 +/- 84.2 and 83.7 +/- 97.9 mg, P < 0.0001). There was no association between morphine consumption and age (r = -0.216). Of the 6% of patients who experienced hypoxemia and 2% who experienced respiratory depression, virtually all had one of three risk factors: bolus dose greater than 1 mg morphine, age greater than 65 years, or intra-abdominal surgery. The most common side effects were nausea and sedation. The incidence of nausea was highest on day 1 (28%) and decreased over the next 2 days (14.3% and 4.7%, respectively). A similar pattern was observed with sedation (incidence over the first 3 days: 28%, 9.3%, and 3.3%, respectively). Overall patient satisfaction scores were high (8.3/10 +/- 1.9). We conclude that the risk of serious complications with PCA is very low, but worrying degrees of hypoxemia and bradypnea do occur. We suggest prescribing regimens that may reduce complications and identify patients at high risk.

The efficacy, applicability and side-effects of postoperative intravenous patient-controlled morphine analgesia: an audit of 1233 Chinese patients

We analyzed data from 1233 Chinese patients of a wide age range who received patient-controlled analgesia (PCA) intravenous morphine for postoperative pain relief, during the period of January 1992 to May 1995. The analgesic regimen was standardized as follows: PCA bolus 1 to 1.5 mg; lock-out interval 5 minutes; one-hour maximum dose 0.075 to 0.1 mg.kg-1 and background infusion 0 or 0.5 mg.h-1. Most patients underwent major surgery that was broadly subclassified according to the anatomical area involved. The median verbal numerical rating scales of pain (0 to 10) at rest and while coughing for the first, second and third 24 hours were 3.0/5.0, 1.5/4.0 and 0/3.0 respectively and the corresponding demand to delivery ratios were 2.8 +/- 2.9, 2.6 +/- 2.4 and 2.4 +/- 2.6. The overall morphine consumptions in 1004 of these Chinese patients were 27.5 +/- 16.8, 17.8 +/- 16.1 and 18.1 +/- 21.0 micrograms.kg-1.h-1 during the first 16, 17 to 41 and 42 to 66 postoperative hours respectively. These figures were the same as for Caucasian patients managed in the same institution. Morphine consumption was significant higher following thoracic, upper abdominal and spinal surgery. Also it was higher in patients younger than 65 years, males, cigarette smokers and those with ASA physical status I or II. The commonest side-effects were nausea (34.5%) and vomiting (18.2%). Bradypnoea and oxygen desaturation occurred in 0.5% and 1.6% respectively. All cases were promptly detected and managed with no adverse outcomes. Most patients were satisfied (76.7% ranked "good") with their postoperative analgesia. The commonest reasons for dissatisfaction were inadequate pain relief, nausea and reluctance to self-control analgesic administration. It is concluded that PCA with intravenous morphine is effective and safe as a routine postoperative technique for Chinese surgical patients.

Comparison of ondansetron and droperidol in reducing postoperative nausea and vomiting associated with patient-controlled analgesia

In a randomised, placebo-controlled trial we have compared the efficacy of ondansetron and droperidol in reducing postoperative nausea and vomiting associated with patient-controlled analgesia after orthopaedic surgery. One hundred and forty five patients, ASA 1 and 2, undergoing major orthopaedic surgery were anaesthetised using a standardised technique. They were randomly allocated to receive patient-controlled analgesia as morphine 1 mg.ml-1 alone; morphine as before plus a single dose of 1.25 mg droperidol together with 0.083 mg.ml-1 in the infusion syringe; or morphine as before plus 4 mg ondansetron and 0.13 mg.ml-1 in the syringe. The patient-controlled analgesia bolus dose was set at 1 ml with a 5 min lockout and a 4 h maximum dose of 30 mg morphine. There was no background infusion. The occurrence of nausea, vomiting and sedation was assessed every 4 h. The incidence of vomiting decreased from 59% in the morphine-only group to 35% and 14% in the droperidol (p < 0.05) and ondansetron groups (p < 0.001) respectively. The number of patients suffering from nausea alone was not significantly different between the three groups, although those in the ondansetron group experienced less severe nausea (p < 0.05) when using a two point scale. The droperidol group had significantly higher sedation scores than the other two groups (p < 0.005). We conclude that ondansetron is superior to droperidol when used with patient-controlled analgesia and causes less sedation.

Compatibility of ondansetron hydrochloride with meperidine hydrochloride for combined administration

OBJECTIVE

To determine the physical compatibility and chemical stability of ondansetron hydrochloride 0.1 and 1 mg/mL with meperidine hydrochloride 4 mg/mL admixed in NaCl 0.9% injection USP.

DESIGN

Triplicate test solutions of the drugs in NaCl 0.9% injection USP were prepared and stored at 4, 22, and 32 degrees C. Samples were removed initially and at various time points over 31 days and were stored at -70 degrees C until they were analyzed. Physical compatibility was assessed by measuring solution turbidity with a color-correcting turbidimeter and particle content with a light-obscuration particle sizer/counter, as well as by visual assessment. Chemical stability of the drugs was determined using a stability-indicating HPLC analytic method. Duplicate determinations were performed on each sample to measure the concentration of each drug.

RESULTS

All admixtures were found to exhibit no visual or subvisual changes of consequence in turbidity or particle content at all observation points. Further, little or no loss of any of the drugs occurred in any concentration throughout the study.

CONCLUSIONS

The physical compatibility and chemical stability of ondansetron hydrochloride with meperidine hydrochloride under the conditions of this study have been established for 7 days at 32 degrees C and 31 days at 4 and 22 degrees C.

Efficacy of patient-controlled analgesia in women cholecystectomy patients

The purpose of this comparative study was to examine differences in pain intensity, sleep disturbance, sleep effectiveness, fatigue, and vigor between patients undergoing cholecystectomy who received either patient-controlled analgesia (PCA) or intramuscular (IM) injections of narcotics for postoperative pain. The PCA group consisted of 16 women, aged 22-58; the IM group consisted of 10 women, aged 22-60. Data were collected on patients' postoperative days 1 and 2. Findings indicated that patients receiving PCA reported less pain on postoperative day 1 and less fatigue on postoperative day 2 than patients receiving IM injections of narcotics.

A comparison of droperidol and cyclizine in the prevention of postoperative nausea and vomiting associated with patient-controlled analgesia

Fifty ASA 1 or 2 patients scheduled to undergo major gynaecological surgery were allocated randomly to one of two groups. All patients received a standard anaesthetic regimen. Patients in group 1 received droperidol 1.25 mg given intravenously 20 min prior to the end of surgery and a patient-controlled analgesia infusion containing morphine 1 mg.ml-1 and droperidol 0.05 mg.ml-1. Patients in group 2 received cyclizine 50 mg by slow intravenous injection 20 min prior to the end of surgery and a patient-controlled analgesia infusion containing morphine 1 mg.ml-1 and cyclizine 2 mg.ml-1. Fifteen of 25 patients (60%) in group 1 and 18 (72%) of 25 in group 2 suffered no nausea or vomiting postoperatively. Two patients (8%) in group 1 and three (12%) in group 2 suffered severe postoperative nausea or vomiting. We conclude that cyclizine is as effective as droperidol in the prevention of postoperative nausea and vomiting when included in a patient-controlled analgesia infusion using morphine.

The antiemetic effectiveness of droperidol during morphine patient-controlled analgesia

This prospective, double-blind study examined the antiemetic effectiveness of the addition of droperidol to a morphine solution for use in patient-controlled analgesia in a group of 50 patients undergoing elective lumbar laminectomy. The addition of 20 mg droperidol to 120 mg morphine in 60 ml saline given by a Baxter 'Infusor' patient-controlled analgesia device reduced the incidence of vomiting as compared to the addition of sodium chloride from 42.8% to 12.5% (p = 0.028) and of nausea from 71.4% to 29.2% (p = 0.005). The proportion of patients requiring rescue antiemetic therapy was reduced from 47.6% to 16.7% (p = 0.025) and the time interval to the first use of rescue antiemetic agent was significantly prolonged (p = 0.029). The use of droperidol was associated with an increased degree of sedation during the first 12 h after operation.

Comparison of different methods of administering droperidol in patient-controlled analgesia in the prevention of postoperative nausea and vomiting

We performed a double-blind, placebo-controlled study to evaluate the different methods of administering droperidol in patients using patient-controlled analgesia (PCA) with morphine. Eighty patients undergoing major orthopedic procedures received temazepam 0.2 mg/kg orally followed by induction of general anesthesia with propofol 2.5 mg/kg, fentanyl 2 micrograms/kg, and vecuronium 0.1 mg/kg. Anesthesia was maintained with nitrous oxide, oxygen, and enflurane. At the end of surgery, all patients received PCA with morphine (0.5 mg/mL, bolus dose 1 mg, and lockout interval 5 min. Before commencement of PCA, patients were randomized to receive droperidol 1.25 mg immediately and, in addition, droperidol 0.16 mg with each PCA dose (Group 1), droperidol 1.25 mg immediately (Group 2), droperidol 0.16 mg with each PCA dose (Group 3), and no droperidol (Group 4). Incidence of nausea and vomiting, request for rescue antiemetics, sedation score, and side effects were recorded every 4 h. Droperidol significantly reduced the incidence of postoperative nausea and vomiting (PONV) (P < 0.01) and request for rescue antiemetic (P < 0.01) compared to placebo. However, there was no difference in the incidence of PONV between droperidol given either as a single dose at the end of surgery (Group 2) or mixed in morphine PCA (Group 3). The addition of droperidol in PCA after an initial dose (Group 1) should be avoided, as it resulted in more sedation and no further reduction in the incidence of PONV compared to Groups 2 and 3.

Shaping attitudes to postoperative pain relief: the role of the acute pain team

Postoperative pain relief is often inadequate. Ignorance and misconceptions about opioids by ward staff contribute to this poor management. The introduction of acute pain teams has done much to improve pain relief for patients. It may also have contributed to changes in attitudes and knowledge of medical and nursing staff. We questioned 48 doctors and nurses on their knowledge and beliefs about postoperative pain relief. Staff members were questioned on two units, one with access to an acute pain team and one without. Over half those on the unit using traditional postoperative care thought patients did not receive adequate pain relief (58%). In comparison, only one respondent from the unit with the pain team thought this was the case (P < 0.001). More staff members that had experience of patient-controlled analgesia (PCA) were optimistic about its benefits than those in the unit with no experience; they were also less concerned about possible side effects. Only one respondent on the unit using PCA thought it carried a risk of drug dependence, compared to over half (55%) of those on the unit with no experience in this technique (P < 0.001). Over two-thirds of staff familiar with PCA thought nursing workload had decreased. Acute pain teams have an important role in educating ward staff. The impact of establishing such teams on staff knowledge and attitudes needs further study to ensure that they can carry out this role most effectively.

Antiemetic efficacy of metoclopramide when included in a patient-controlled analgesia infusion

A double-blind, randomised, controlled trial was performed to assess the antiemetic efficacy of metoclopramide when included in a morphine patient-controlled analgesia regimen. Fifty ASA grade 1 or 2 patients scheduled for elective intermediate or major gynaecological surgery were allocated into one of two groups. All patients received a standardised anaesthetic and metoclopramide 5 mg was given intravenously 10 min before the end of the procedure. Group 1 received a patient-controlled analgesia regimen using morphine 1 mg.ml-1 solution. Group 2 received a patient-controlled analgesia regimen using morphine 1mg.ml-1 with metoclopramide 0.5 mg.ml-1 solution. Postoperative antiemetic treatment was with metoclopramide 10 mg intramuscularly or cyclizine 50 mg intramuscularly if this was ineffective. Pain scores, sedation scores, and morphine requirement were not significantly different between the groups. There was no difference in nausea scores between the groups, but more patients suffered moderate or severe nausea in group 1 (10 patients) than group 2 (three patients, p < 0.026). We conclude that metoclopramide, when included in a patient-controlled analgesia regimen, reduces the incidence of moderate to severe nausea, but not the overall incidence of nausea.