Premedication with intramuscular dixyrazine: (Esucos). A controlled double-blind comparison with morphine-scopolamine and placebo

Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network meta-analysis

BACKGROUND

Postoperative nausea and vomiting (PONV) is a common adverse effect of anaesthesia and surgery. Up to 80% of patients may be affected. These outcomes are a major cause of patient dissatisfaction and may lead to prolonged hospital stay and higher costs of care along with more severe complications. Many antiemetic drugs are available for prophylaxis. They have various mechanisms of action and side effects, but there is still uncertainty about which drugs are most effective with the fewest side effects.

OBJECTIVES

• To compare the efficacy and safety of different prophylactic pharmacologic interventions (antiemetic drugs) against no treatment, against placebo, or against each other (as monotherapy or combination prophylaxis) for prevention of postoperative nausea and vomiting in adults undergoing any type of surgery under general anaesthesia • To generate a clinically useful ranking of antiemetic drugs (monotherapy and combination prophylaxis) based on efficacy and safety • To identify the best dose or dose range of antiemetic drugs in terms of efficacy and safety SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, the Cumulative Index to Nursing and Allied Health Literature (CINAHL), the World Health Organization International Clinical Trials Registry Platform (WHO ICTRP), ClinicalTrials.gov, and reference lists of relevant systematic reviews. The first search was performed in November 2017 and was updated in April 2020. In the update of the search, 39 eligible studies were found that were not included in the analysis (listed as awaiting classification).

SELECTION CRITERIA

Randomized controlled trials (RCTs) comparing effectiveness or side effects of single antiemetic drugs in any dose or combination against each other or against an inactive control in adults undergoing any type of surgery under general anaesthesia. All antiemetic drugs belonged to one of the following substance classes: 5-HT₃ receptor antagonists, D₂ receptor antagonists, NK₁ receptor antagonists, corticosteroids, antihistamines, and anticholinergics. No language restrictions were applied. Abstract publications were excluded.

DATA COLLECTION AND ANALYSIS

A review team of 11 authors independently assessed trials for inclusion and risk of bias and subsequently extracted data. We performed pair-wise meta-analyses for drugs of direct interest (amisulpride, aprepitant, casopitant, dexamethasone, dimenhydrinate, dolasetron, droperidol, fosaprepitant, granisetron, haloperidol, meclizine, methylprednisolone, metoclopramide, ondansetron, palonosetron, perphenazine, promethazine, ramosetron, rolapitant, scopolamine, and tropisetron) compared to placebo (inactive control). We performed network meta-analyses (NMAs) to estimate the relative effects and ranking (with placebo as reference) of all available single drugs and combinations. Primary outcomes were vomiting within 24 hours postoperatively, serious adverse events (SAEs), and any adverse event (AE). Secondary outcomes were drug class-specific side effects (e.g. headache), mortality, early and late vomiting, nausea, and complete response. We performed subgroup network meta-analysis with dose of drugs as a moderator variable using dose ranges based on previous consensus recommendations. We assessed certainty of evidence of NMA treatment effects for all primary outcomes and drug class-specific side effects according to GRADE (CINeMA, Confidence in Network Meta-Analysis). We restricted GRADE assessment to single drugs of direct interest compared to placebo.

MAIN RESULTS

We included 585 studies (97,516 randomized participants). Most of these studies were small (median sample size of 100); they were published between 1965 and 2017 and were primarily conducted in Asia (51%), Europe (25%), and North America (16%). Mean age of the overall population was 42 years. Most participants were women (83%), had American Society of Anesthesiologists (ASA) physical status I and II (70%), received perioperative opioids (88%), and underwent gynaecologic (32%) or gastrointestinal surgery (19%) under general anaesthesia using volatile anaesthetics (88%). In this review, 44 single drugs and 51 drug combinations were compared. Most studies investigated only single drugs (72%) and included an inactive control arm (66%). The three most investigated single drugs in this review were ondansetron (246 studies), dexamethasone (120 studies), and droperidol (97 studies). Almost all studies (89%) reported at least one efficacy outcome relevant for this review. However, only 56% reported at least one relevant safety outcome. Altogether, 157 studies (27%) were assessed as having overall low risk of bias, 101 studies (17%) overall high risk of bias, and 327 studies (56%) overall unclear risk of bias. Vomiting within 24 hours postoperatively Relative effects from NMA for vomiting within 24 hours (282 RCTs, 50,812 participants, 28 single drugs, and 36 drug combinations) suggest that 29 out of 36 drug combinations and 10 out of 28 single drugs showed a clinically important benefit (defined as the upper end of the 95% confidence interval (CI) below a risk ratio (RR) of 0.8) compared to placebo. Combinations of drugs were generally more effective than single drugs in preventing vomiting. However, single NK₁ receptor antagonists showed treatment effects similar to most of the drug combinations. High-certainty evidence suggests that the following single drugs reduce vomiting (ordered by decreasing efficacy): aprepitant (RR 0.26, 95% CI 0.18 to 0.38, high certainty, rank 3/28 of single drugs); ramosetron (RR 0.44, 95% CI 0.32 to 0.59, high certainty, rank 5/28); granisetron (RR 0.45, 95% CI 0.38 to 0.54, high certainty, rank 6/28); dexamethasone (RR 0.51, 95% CI 0.44 to 0.57, high certainty, rank 8/28); and ondansetron (RR 0.55, 95% CI 0.51 to 0.60, high certainty, rank 13/28). Moderate-certainty evidence suggests that the following single drugs probably reduce vomiting: fosaprepitant (RR 0.06, 95% CI 0.02 to 0.21, moderate certainty, rank 1/28) and droperidol (RR 0.61, 95% CI 0.54 to 0.69, moderate certainty, rank 20/28). Recommended and high doses of granisetron, dexamethasone, ondansetron, and droperidol showed clinically important benefit, but low doses showed no clinically important benefit. Aprepitant was used mainly at high doses, ramosetron at recommended doses, and fosaprepitant at doses of 150 mg (with no dose recommendation available). Frequency of SAEs Twenty-eight RCTs were included in the NMA for SAEs (10,766 participants, 13 single drugs, and eight drug combinations). The certainty of evidence for SAEs when using one of the best and most reliable anti-vomiting drugs (aprepitant, ramosetron, granisetron, dexamethasone, ondansetron, and droperidol compared to placebo) ranged from very low to low. Droperidol (RR 0.88, 95% CI 0.08 to 9.71, low certainty, rank 6/13) may reduce SAEs. We are uncertain about the effects of aprepitant (RR 1.39, 95% CI 0.26 to 7.36, very low certainty, rank 11/13), ramosetron (RR 0.89, 95% CI 0.05 to 15.74, very low certainty, rank 7/13), granisetron (RR 1.21, 95% CI 0.11 to 13.15, very low certainty, rank 10/13), dexamethasone (RR 1.16, 95% CI 0.28 to 4.85, very low certainty, rank 9/13), and ondansetron (RR 1.62, 95% CI 0.32 to 8.10, very low certainty, rank 12/13). No studies reporting SAEs were available for fosaprepitant. Frequency of any AE Sixty-one RCTs were included in the NMA for any AE (19,423 participants, 15 single drugs, and 11 drug combinations). The certainty of evidence for any AE when using one of the best and most reliable anti-vomiting drugs (aprepitant, ramosetron, granisetron, dexamethasone, ondansetron, and droperidol compared to placebo) ranged from very low to moderate. Granisetron (RR 0.92, 95% CI 0.80 to 1.05, moderate certainty, rank 7/15) probably has no or little effect on any AE. Dexamethasone (RR 0.77, 95% CI 0.55 to 1.08, low certainty, rank 2/15) and droperidol (RR 0.89, 95% CI 0.81 to 0.98, low certainty, rank 6/15) may reduce any AE. Ondansetron (RR 0.95, 95% CI 0.88 to 1.01, low certainty, rank 9/15) may have little or no effect on any AE. We are uncertain about the effects of aprepitant (RR 0.87, 95% CI 0.78 to 0.97, very low certainty, rank 3/15) and ramosetron (RR 1.00, 95% CI 0.65 to 1.54, very low certainty, rank 11/15) on any AE. No studies reporting any AE were available for fosaprepitant. Class-specific side effects For class-specific side effects (headache, constipation, wound infection, extrapyramidal symptoms, sedation, arrhythmia, and QT prolongation) of relevant substances, the certainty of evidence for the best and most reliable anti-vomiting drugs mostly ranged from very low to low. Exceptions were that ondansetron probably increases headache (RR 1.16, 95% CI 1.06 to 1.28, moderate certainty, rank 18/23) and probably reduces sedation (RR 0.87, 95% CI 0.79 to 0.96, moderate certainty, rank 5/24) compared to placebo. The latter effect is limited to recommended and high doses of ondansetron. Droperidol probably reduces headache (RR 0.76, 95% CI 0.67 to 0.86, moderate certainty, rank 5/23) compared to placebo. We have high-certainty evidence that dexamethasone (RR 1.00, 95% CI 0.91 to 1.09, high certainty, rank 16/24) has no effect on sedation compared to placebo. No studies assessed substance class-specific side effects for fosaprepitant. Direction and magnitude of network effect estimates together with level of evidence certainty are graphically summarized for all pre-defined GRADE-relevant outcomes and all drugs of direct interest compared to placebo in http://doi.org/10.5281/zenodo.4066353.

AUTHORS' CONCLUSIONS

We found high-certainty evidence that five single drugs (aprepitant, ramosetron, granisetron, dexamethasone, and ondansetron) reduce vomiting, and moderate-certainty evidence that two other single drugs (fosaprepitant and droperidol) probably reduce vomiting, compared to placebo. Four of the six substance classes (5-HT₃ receptor antagonists, D₂ receptor antagonists, NK₁ receptor antagonists, and corticosteroids) were thus represented by at least one drug with important benefit for prevention of vomiting. Combinations of drugs were generally more effective than the corresponding single drugs in preventing vomiting. NK₁ receptor antagonists were the most effective drug class and had comparable efficacy to most of the drug combinations. 5-HT₃ receptor antagonists were the best studied substance class. For most of the single drugs of direct interest, we found only very low to low certainty evidence for safety outcomes such as occurrence of SAEs, any AE, and substance class-specific side effects. Recommended and high doses of granisetron, dexamethasone, ondansetron, and droperidol were more effective than low doses for prevention of vomiting. Dose dependency of side effects was rarely found due to the limited number of studies, except for the less sedating effect of recommended and high doses of ondansetron. The results of the review are transferable mainly to patients at higher risk of nausea and vomiting (i.e. healthy women undergoing inhalational anaesthesia and receiving perioperative opioids). Overall study quality was limited, but certainty assessments of effect estimates consider this limitation. No further efficacy studies are needed as there is evidence of moderate to high certainty for seven single drugs with relevant benefit for prevention of vomiting. However, additional studies are needed to investigate potential side effects of these drugs and to examine higher-risk patient populations (e.g. individuals with diabetes and heart disease).

Scopolamine Use in the Perioperative Patient: A Systematic Review

Scopolamine is an antiemetic agent used for postoperative nausea and vomiting prevention; however, it has anticholinergic effects (eg, bradycardia, dry mouth, dizziness, visual disturbances). Avoiding scopolamine use in specific populations is crucial to prevent adverse effects and harm to patients. This systematic review describes the anticholinergic effects of scopolamine in perioperative patient populations. After searching the available literature, we reviewed the eligible articles to determine whether they met the inclusion criteria (eg, full text, English language, included a discussion of scopolamine's anticholinergic effects in perioperative patients). Twenty-six articles were included in this review. We used The Johns Hopkins Research Evidence Appraisal Tool to appraise the literature. The results of this literature review reveal that clinicians should avoid administering scopolamine to certain perioperative patient populations (ie, pediatric, older adult).

WITHDRAWN: Drugs for preventing postoperative nausea and vomiting

BACKGROUND

Drugs can prevent postoperative nausea and vomiting, but their relative efficacies and side effects have not been compared within one systematic review.

OBJECTIVES

The objective of this review was to assess the prevention of postoperative nausea and vomiting by drugs and the development of any side effects.

SEARCH METHODS

We searched The Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, Issue 2, 2004), MEDLINE (January 1966 to May 2004), EMBASE (January 1985 to May 2004), CINAHL (1982 to May 2004), AMED (1985 to May 2004), SIGLE (to May 2004), ISI WOS (to May 2004), LILAC (to May 2004) and INGENTA bibliographies.

SELECTION CRITERIA

We included randomized controlled trials that compared a drug with placebo or another drug, or compared doses or timing of administration, that reported postoperative nausea or vomiting as an outcome.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial quality and extracted outcome data.

MAIN RESULTS

We included 737 studies involving 103,237 people. Compared to placebo, eight drugs prevented postoperative nausea and vomiting: droperidol, metoclopramide, ondansetron, tropisetron, dolasetron, dexamethasone, cyclizine and granisetron. Publication bias makes evidence for differences among these drugs unreliable. The relative risks (RR) versus placebo varied between 0.60 and 0.80, depending upon the drug and outcome. Evidence for side effects was sparse: droperidol was sedative (RR 1.32) and headache was more common after ondansetron (RR 1.16).

AUTHORS' CONCLUSIONS

Either nausea or vomiting is reported to affect, at most, 80 out of 100 people after surgery. If all 100 of these people are given one of the listed drugs, about 28 would benefit and 72 would not. Nausea and vomiting are usually less common and, therefore, drugs are less useful. For 100 people, of whom 30 would vomit or feel sick after surgery if given placebo, 10 people would benefit from a drug and 90 would not. Between one to five patients out of every 100 people may experience a mild side effect, such as sedation or headache, when given an antiemetic drug. Collaborative research should focus on determining whether antiemetic drugs cause more severe, probably rare, side effects. Further comparison of the antiemetic effect of one drug versus another is not a research priority.

Transdermal scopolamine for the prevention of postoperative nausea and vomiting: a systematic review and meta-analysis

BACKGROUND

Transdermal scopolamine (TDS) is a potential long-acting prophylactic antiemetic initially developed to prevent motion sickness. TDS is a centrally acting anticholinergic agent that was approved in 2001 by the US Food and Drug Administration for the prevention of postoperative nausea and vomiting (PONV). Although TDS has been reported to be clinically efficacious in the prevention of PONV, several adverse events (AEs), such as sedation, dry mouth, blurred vision, central cholinergic syndrome, and confusion (particularly in elderly patients with mild cognitive impairment), are potential concerns.

OBJECTIVE

The aim of this study was to explore the efficacy and tolerability of TDS in the prevention of PONV in adults.

METHODS

A systematic search of PubMed, EMBASE, and the Cochrane Library for randomized controlled trials in adults that compared the effects of TDS and placebo on postoperative nausea, vomiting, and PONV was conducted in March 2009, and an update was conducted in July 2010. Without any language restrictions, a search with the following terms was performed: postoperative, postoperative, postanesthe*, postanaesthe*, post-anesthe*, post-anaesthe*, anesthesia, anaesthesia, surgery, surgeries, surgical, nausea, vomiting, emesis, retching, scopolamine, and hyoscine. Identified studies were then hand-searched for further relevant literature.

RESULTS

Data from 25 randomized controlled trials were analyzed (N = 3298). In the postanesthesia care unit, TDS was associated with a significantly reduced risk for postoperative nausea compared with placebo (relative risk [RR] = 0.77; 95% CI, 0.61-0.98; P = 0.03). TDS was also associated with a significantly reduced risk for postoperative nausea (RR = 0.59; 95% CI, 0.48-0.73; P < 0.001), postoperative vomiting (RR = 0.68; 95% CI, 0.61-0.76; P < 0.001), and PONV (RR = 0.73; 95% CI, 0.60-0.88; P = 0.001) during the first 24 hours after the start of anesthesia. TDS appeared to be effective compared with placebo in the prevention of postoperative nausea when treatment was initiated the night before (early application) (RR = 0.56; 95% CI, 0.41-0.75; P < 0.001) or on the day of surgery (late application) (RR = 0.61; 95% CI, 0.47-0.79; P < 0.001). TDS was associated with a higher prevalence of visual disturbances at 24 to 48 hours compared with placebo (RR = 3.35; 95% CI, 1.78-6.32). Analyses of confusion and other AEs did not show a significant association with TDS.

CONCLUSIONS

In this systematic review and metaanalysis, TDS was associated with significant reductions in PONV with both early and late patch application during the first 24 hours after the start of anesthesia. TDS was associated with a higher prevalence of visual disturbances at 24 to 48 hours after surgery, but no other AEs, compared with placebo.

Drugs for preventing postoperative nausea and vomiting

BACKGROUND

Drugs can prevent postoperative nausea and vomiting, but their relative efficacies and side effects have not been compared within one systematic review.

OBJECTIVES

The objective of this review was to assess the prevention of postoperative nausea and vomiting by drugs and the development of any side effects.

SEARCH STRATEGY

We searched The Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, Issue 2, 2004), MEDLINE (January 1966 to May 2004), EMBASE (January 1985 to May 2004), CINAHL (1982 to May 2004), AMED (1985 to May 2004), SIGLE (to May 2004), ISI WOS (to May 2004), LILAC (to May 2004) and INGENTA bibliographies.

SELECTION CRITERIA

We included randomized controlled trials that compared a drug with placebo or another drug, or compared doses or timing of administration, that reported postoperative nausea or vomiting as an outcome.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial quality and extracted outcome data.

MAIN RESULTS

We included 737 studies involving 103,237 people. Compared to placebo, eight drugs prevented postoperative nausea and vomiting: droperidol, metoclopramide, ondansetron, tropisetron, dolasetron, dexamethasone, cyclizine and granisetron. Publication bias makes evidence for differences among these drugs unreliable. The relative risks (RR) versus placebo varied between 0.60 and 0.80, depending upon the drug and outcome. Evidence for side effects was sparse: droperidol was sedative (RR 1.32) and headache was more common after ondansetron (RR 1.16).

AUTHORS' CONCLUSIONS

Either nausea or vomiting is reported to affect, at most, 80 out of 100 people after surgery. If all 100 of these people are given one of the listed drugs, about 28 would benefit and 72 would not. Nausea and vomiting are usually less common and, therefore, drugs are less useful. For 100 people, of whom 30 would vomit or feel sick after surgery if given placebo, 10 people would benefit from a drug and 90 would not. Between one to five patients out of every 100 people may experience a mild side effect, such as sedation or headache, when given an antiemetic drug. Collaborative research should focus on determining whether antiemetic drugs cause more severe, probably rare, side effects. Further comparison of the antiemetic effect of one drug versus another is not a research priority.

The efficacy and safety of transdermal scopolamine for the prevention of postoperative nausea and vomiting: a quantitative systematic review

The role of scopolamine administered via transdermal therapeutic systems in the prevention of postoperative vomiting, nausea, and nausea and vomiting is unclear. We performed a systematic search for full reports of randomized comparisons of transdermal scopolamine with inactive control. Dichotomous data were extracted. In the meta-analysis, relative risks and numbers-needed-to-treat/harm were calculated with 95% confidence intervals (CI). In 23 trials, 979 patients received transdermal scopolamine, and 984 patients received placebo. Sensitivity analyses were performed using restricted data for truncated control event rates (40%-80%) and for large trials. With these data, the relative risks for postoperative vomiting (five reports), nausea (five reports), nausea and vomiting (eight reports), and rescue treatment (three reports) were 0.69 (95% CI, 0.58-0.82), 0.69 (95% CI, 0.54-0.87), 0.76 (95% CI, 0.66-0.88), and 0.68 (95% CI, 0.54-0.85), respectively. This means that of 100 patients who receive transdermal scopolamine, approximately 17 will not experience postoperative vomiting who would have done so had they all received a placebo. However, 18 of 100 patients will have visual disturbances, eight will report dry mouth, two will report dizziness, one will be classified as being agitated, and 1-13 patients who are prescribed transdermal scopolamine will not use it correctly. The timing of application does not alter efficacy.

IMPLICATIONS

Of 100 patients who receive transdermal scopolamine, approximately 17 will not vomit in the postoperative period who would have done so had they all received a placebo. However, 18 of 100 patients will have visual disturbances, and eight will report dry mouth. Incorrect use further limits its efficacy.

Local anaesthesia and propofol-fentanyl sedation for carotid artery surgery

BACKGROUND

In patients undergoing carotid artery surgery with local anaesthesia (LA), a sedative/analgesic pharmacological supplement is appropriate in most cases in order to provide comfort. This adjunct should not preclude continuous clinical neurological monitoring. The aim was to investigate if a combination of fentanyl and propofol to supplement LA would provide comfort for the patient, allow continuous clinical neurological monitoring and absence of difficulties for the anaesthetist, and good conditions for surgery, including insertion of a shunt if this should become necessary.

METHODS

During a 1-year period low doses of propofol and fentanyl were used to supplement LA in 36 cases of carotid artery surgery in 34 consecutive patients. A shunt was only used if neurological dysfunction occurred. Data on haemodynamics, pulmonary gas exchange, clinical neurological monitoring, and subjective opinions from patients, surgeons and anaesthetists were obtained. Morbidity within 30 days was documented.

RESULTS

Conversion to general anaesthesia was undertaken in one patient, previously operated on the same artery, who became unconscious due to a stroke during manipulation of the artery before arteriotomy. No other adverse outcome was found within 30 days. In the remaining 35 cases the procedures were carried out under LA. Stump pressures below 50 mmHg were found in 17/35 cases. Intraoperative neurological dysfunction was detected in 10/35 cases (stump pressures between 23 and 60 mmHg). Shunting was easily performed, and rapidly relieved the neurologic symptoms in all these patients. Intraoperative respiratory and haemodynamic control was satisfactory. Ease of performance, including clinical neurological monitoring, was acknowledged by both anaesthetists and surgeons, and all 33 patients (35 operations) who were accessible for a postoperative interview stated that they would prefer the same regimen in the case of further surgery.

CONCLUSION

The number of cases in this open, uncontrolled study does not permit an evaluation of this anaesthetic and sedative technique in terms of neurological and cardiac outcome. Thus, we simply want to inform about our positive experiences regarding patient acceptance and ease of performance in all relevant respects when fentanyl and propofol are used to supplement LA for carotid artery surgery.

A prospective survey of postoperative nausea and vomiting with special regard to incidence and relations to patient characteristics, anesthetic routines and surgical procedures

We performed a prospective study on 421 patients subjected to routine general-, orthopaedic-, urologic-, gynecological and paediatric surgery to estimate the current incidences of nausea and vomiting during the first 24 hours after surgery. The overall incidences of postoperative nausea or vomiting were 17% and 28%, respectively. Postoperative emetic symptoms were not related to age in adults. Women had more often emetic symptoms than men (P < 0.01). In general, opiate premedication was more frequently associated with postoperative nausea and vomiting than benzodiazepines (P < 0.01), but in otherwise comparable subgroups of patients undergoing major surgery, this difference was not confirmed. Balanced general anaesthesia caused more nausea (23%) and vomiting (53%) than face-mask anaesthesia (13% and 15%, respectively) or regional blocks (12% and 7%, respectively) (P < 0.001). There was a positive correlation between the duration of anaesthesia and the incidence of postoperative emetic symptoms (P < 0.001). The incidences of postoperative nausea and vomiting after abdominal surgery were 23% and 58% respectively. Corresponding figures for orthopaedic surgery were 25% and 34%, other kinds of extra-abdominal surgery 18% and 32% and for laparoscopy 21% and 25%. After minor gynecological-, urological- and paediatric surgery the incidences were less than 20%. In conclusion female gender, balanced anaesthesia, lengthy duration of anaesthesia, and abdominal and orthopaedic operations appeared to be most frequently associated with postoperative emetic symptoms.

Oral premedication one hour before minor gynaecological surgery--does it have any effect? A comparison between ketobemidone, lorazepam, propranolol and placebo

The purpose of the present study was to compare the effects of oral premedication with ketobemidone 5 mg, lorazepam 1 mg, propranolol 40 mg or placebo, given about an hour prior to anaesthesia, in a prospective randomized double-blind fashion. One hundred and twenty ASA I female patients scheduled for elective laparoscopy were randomly prescribed one of the study drugs. Patient evaluation of anxiety, nurse evaluation of premedication, induction and postoperative course were studied. Ninety-three of the 120 patients (78%) experienced no change or a decrease in anxiety, regardless of type of active drug or placebo administered. Eighty-eight of the patients (73%) were considered adequately premedicated by the nurse observer, with no differences between the groups. Pre induction pulse rate, blood pressure and amount of induction agent needed was also similar between the four groups of patients. No major differences could be seen during the postoperative course. We found no major effects of any of the active drugs studied compared to placebo. Routine use of small doses of oral premedication one hour before elective surgery among low anxiety patients could probably be omitted.

CSF concentrations and clinical effects following intravenous dixyrazine premedication

Single concurrent plasma and lumbar spinal fluid samples were collected from twenty-two patients given IV dixyrazine 0.15 mg/kg, 10-106 min earlier in an open study. Dixyrazine penetrated rapidly into the spinal fluid; the CSF/P ratio was 0.3 by 10 min after drug administration and persisted at that level during the study period. The uncontrolled sedative and anxiolytic effects assessed by the patients were slight, and were correlated with the CSF drug concentrations only during the first 30 min after medication.

Dixyrazine premedication for cataract surgery. A comparison with diazepam

Peroral dixyrazine (15-30 mg, n = 50) and diazepam (4-10 mg, n = 50) were used as premedicants for geriatric patients having cataract surgery under regional block. Compared to the diazepam patients, a larger number of the dixyrazine medicated patients appeared anxious, and there was a statistically significant difference between the groups, when summing up changes in anxiety throughout the study period. The dixyrazine patients needed more frequent supplementation with intravenous sedative drugs, compared with their diazepam counterparts. Peroral dixyrazine is an applicable choice for calm patients, when only slight sedation, or avoidance of somnolence are required.

The effects of prophylactic dixyrazine on postoperative vomiting after two different anaesthetic methods for squint surgery in children

The incidence of postoperative vomiting after squint surgery was studied for two anaesthetic techniques with and without prophylactic dixyrazine. After induction, anaesthesia was maintained with either fentanyl/pancuronium/nitrous oxide or halothane/nitrous oxide in two randomly selected groups of 58 children each. Half of the children in each group were randomly allocated to receive dixyrazine 0.25 mg kg-1 i.v. after surgery had been completed but before reversal of muscle relaxants or termination of anaesthesia. With prophylactic dixyrazine the incidence of postoperative vomiting was significantly reduced from 69% (20/29) to 21% (6/29) in the fentanyl group and from 45% (13/29) to 10% (3/29) in the halothane group. Without prophylactic dixyrazine, 20 of 29 children in the fentanyl group vomited compared to 13 of 29 in the halothane group (n.s.). Thus, prophylactic dixyrazine reduced the incidence of vomiting in children given either opioid or halothane anaesthesia for squint surgery. In comparable groups avoidance of opioid anaesthetic technique and use of prophylactic dixyrazine resulted in a greatly reduced incidence of vomiting.

Premedication before elective breast surgery, a comparison between ketobemidone and midazolam

One hundred female patients scheduled for elective breast surgery (mean age 60 +/- 11 years were randomly assigned to receive one of two premedications: ketobemidone (Ketogan) 1-1.5 ml or midazolam 4-5 mg, intramuscularly. The effects on preoperative anxiety and postoperative emetic sequelae were studied. All patients were anaesthetised with thiopentone, fentanyl and atracurium, and ventilated with a mixture of nitrous oxide in oxygen with supplementary isoflurane. Sixty-nine percent of the midazolam- and 50% of the ketobemidone-premedicated patients experienced a reduction in anxiety. Midazolam was found to be more effective than ketobemidone in reducing anxiety among more tense patients--those with a VAS grading before premedication of 2 or more (P less than 0.05). Midazolam-premedicated patients were also assessed by observers as being more relaxed (P less than 0.05). No difference was seen in the frequency of emetic sequelae: 20 patients in the midazolam group and 14 patients in the ketobemidone group vomited once or more during the 24-h observation period. There was no difference between the two groups in time until an analgetic was required. In conclusion, midazolam seemed more effective in reducing preoperative anxiety than ketobemidone without any negative effects on postoperative emesis or time until an analgetic was required.

Postoperative emesis after pediatric strabismus surgery: the effect of dixyrazine compared to droperidol

Sixty-one children, ASA physical status I, aged 2-14 years, admitted for strabismus surgery were studied. All were premedicated with diazepam and atropin rectally. Anesthesia was induced with thiopental or with halothane on a facemask, and succinylcholine was given to facilitate tracheal intubation. Anesthesia was maintained with halothane and nitrous oxide. Each child was randomly assigned to receive either no antiemetic prophylaxis (control), droperidol 0.075 mg/kg, or dixyrazine 0.25 mg/kg. The drugs were injected intravenously at the end of surgery. The incidence of vomiting during the following 24 h was 65% in the control group, 48% in the droperidol group, and 25% in the dixyrazine group (P less than 0.05 as compared to the control group). Four hours after the operation, six children in the droperidol group and none in the dixyrazine group (P less than 0.05) were difficult to arouse. It is concluded that dixyrazine reduces the incidence of postoperative vomiting without causing heavy sedation.