Subhypnotic doses of propofol possess direct antiemetic properties

Postoperative nausea and vomiting. A comparison between intravenous and inhalation anaesthesia in breast surgery

Nausea and vomiting during the first 24 postoperative hours after breast surgery were studied. Ninety patients scheduled for elective breast surgery were randomly assigned to one of three anaesthetic methods: total intravenous anaesthesia with propofol, or propofol or thiopental for induction followed by isoflurane anaesthesia. All three groups received fentanyl for peroperative analgesia. A total of 46 (51%) patients experienced emetic sequelae: 19 (21%) complained about nausea and another 27 (30%) vomited once or more during the postoperative course. More than 50% of the patients with nausea and 70% with vomiting first suffered from these symptoms in the surgical wards after leaving the postoperative unit. Nausea and vomiting were seen in 18 (60%), 13 (43%) and 15 (50%) for the groups propofol-propofol, propofol-isoflurane and thiopental-isoflurane, respectively. In conclusion, every second patient experienced nausea or vomiting after breast surgery, the majority of these emetic symptoms occurring after leaving the postoperative unit. Propofol for induction or as a main anaesthetic did not make any major difference with regard to postoperative nausea or vomiting.

[Effects of Diprivan on nausea and vomiting]

Total intravenous anaesthesia using propofol is indicated in the following cases: patients with a previous history of postoperative nausea or vomiting; surgery of the middle ear; gynaecological procedures involving laparotomy; ENT and squint surgery in children. Up to now, the relationship between the clinical benefit (less incidence of postoperative nausea and vomiting) and intrinsec anti-emetic properties of propofol is not included in the regulatory labelling.

Recovery following outpatient anesthesia: use of enflurane versus propofol

STUDY OBJECTIVE

To compare the intraoperative conditions and postoperative recovery of patients following the use of either propofol-nitrous oxide (N2O) or enflurane-N2O for maintenance of outpatient anesthesia.

DESIGN

Randomized, single-blind study.

SETTING

University hospital outpatient surgery center.

PATIENTS

61 ASA physical status I and II, healthy female outpatients undergoing laparoscopic surgery.

INTERVENTIONS

Patients were randomly assigned to one of three anesthetic regimens. Group 1 (control) received thiopental sodium 4 mg/kg intravenously (i.v.), followed by 0.5% to 1.5% enflurane and 67% N2O in oxygen (O2). Group 2 received propofol 2 mg/kg i.v., followed by 0.5% to 1.5% enflurane and 67% N2O in O2. Group 3 received propofol 2 mg/kg i.v., followed by propofol 50 to 160 micrograms/kg/min i.v. and 67% N2O in O2. All patients received succinylcholine 1 mg/kg i.v. to facilitate tracheal intubation and atracurium 10 to 20 mg i.v. to provide adequate relaxation during the maintenance period.

MEASUREMENTS AND MAIN RESULTS

Recovery from anesthesia was assessed by a research nurse who was unaware of the anesthetic technique used. The mean +/- SD time to eye opening was significantly longer in the thiopental-enflurane-N2O group (Group 1) than in the propofol-propofol-N2O group (Group 3) (6.1 +/- 2.5 minutes vs. 3.5 +/- 2.8 minutes, respectively). In addition, the mean time to respond to verbal commands was significantly shorter in the propofol induction groups compared with the thiopental induction group. However, the use of enflurane versus propofol for maintenance of anesthesia did not significantly prolong the time from arrival in the recovery room to sitting, tolerating oral fluids, walking, or being judged "fit for discharge." There were no differences among the three groups with respect to postoperative pain or analgesic requirements. Finally, patients who received enflurane for maintenance of anesthesia had a significantly higher frequency of nausea and vomiting than the propofol maintenance group.

CONCLUSION

Induction of anesthesia with propofol is associated with a more rapid emergence from anesthesia than induction with thiopental. Maintenance of anesthesia with enflurane did not prolong recovery compared with maintenance with propofol, but enflurane was associated with increased frequency of postoperative nausea and vomiting.

Impact of newer drugs and techniques on the quality of ambulatory anesthesia

Recent pharmacologic and technologic advances in anesthesia and surgery allow outpatients with complex medical problems to undergo a wide variety of diagnostic and surgical procedures on an ambulatory basis. Increasingly, however, anesthesia practitioners, as well as pharmacy and therapeutic committees, are demanding proof that a new, more costly drug or medical device is superior to existing products in achieving its desired effect, is associated with fewer adverse effects, enhances efficiency, and reduces health care costs. The new field of pharmacoeconomics has emphasized the importance of cost-effectiveness analyses that consider both direct and indirect costs of newer drugs and therapeutic modalities. As new biomedical technology is introduced to facilitate the perioperative management of patients (e.g., computerized anesthesia information management systems), evidence that these systems enhance our ability to continue to provide high-quality, cost-effective health care will assume increasing importance. Limitations in health care resources necessitate a careful reevaluation of our clinical practices with respect to choice of drugs, supplies, equipment, and even discharge criteria. Ambulatory anesthesia and surgery will continue to increase because of the potential cost savings for patients undergoing elective operations on an outpatient basis. However, the challenge we face will be to continue to provide high-quality anesthesia care at a reduced cost. A careful examination of commonly accepted (but unproven) clinical practice patterns will be necessary to meet this challenge.

Nausea: the most important factor determining length of stay after ambulatory anaesthesia. A comparative study of isoflurane and/or propofol techniques

Speed of recovery and length of stay in hospital were studied in 95 ambulatory patients undergoing laparoscopy or arthroscopy. The patients were divided into three groups regarding maintenance of anaesthesia. Group A (n = 32) received isoflurane 0.7% end-tidally, group B (n = 31) propofol infusion for 25 min and thereafter isoflurane, and group C (n = 32) received an infusion of propofol throughout the procedure. Recovery was assessed by a combination of the Maddox-Wing, the Choice Reaction Time test and p-deletion. The awakening period was somewhat shorter in group A, but psychomotor recovery was somewhat slower compared to groups B and C. The length of stay in hospital depended on whether the patient was nauseated or not. In group A, 44% suffered from nausea requiring medical intervention compared to 13% and 19% in groups B and C, respectively. The stay in hospital was 235 +/- 90 min (mean +/- standard deviation) in group A compared to 184 +/- 56 min and 197 +/- 55 min in groups B and C, respectively. The non-nauseated patients in group A had a stay in hospital of 188 +/- 55 min compared to 184 +/- 52 and 184 +/- 37 in the non-nauseated patients in groups B and C, respectively. In total, the nauseated patients (n = 24) stayed 267 +/- 95 min compared to 185 +/- 47 min for the non-nauseated patients (n = 71), P < 0.001. We found nausea to be the most important factor determining length of stay after ambulatory anaesthesia.(ABSTRACT TRUNCATED AT 250 WORDS)

Urinary serotonin metabolite excretion during cisplatin chemotherapy

BACKGROUND

Nausea and vomiting associated with cisplatin chemotherapy is a source of major morbidity that remains difficult to control. Acute phase (0-24 hours after induction of chemotherapy) nausea and vomiting parallels plasma serotonin release, which explains the effectiveness of 5HT3 antagonists; serotonin release in the delayed phase (24-48 hours after induction), during which consistent antiemetic control remains elusive, has not been investigated. The effect of propofol, a recent addition to the antiemetic armamentarium, on this serotonin release has not been studied.

METHODS

Ten women with nausea and vomiting refractory to ondansetron and dexamethasone prophylaxis in their first cisplatin chemotherapy cycle were studied. Serial urinary 5-hydroxyindoleacetic acid (5-HIAA) levels were determined during a 48-hour period in 30 subsequent cycles, conducted under ondansetron/dexamethasone prophylaxis together with a propofol infusion.

RESULTS

There was a significant urinary 5-HIAA peak 6 hours after induction of chemotherapy, with no peaks thereafter. Propofol did not inhibit serotonin release.

CONCLUSIONS

Cisplatin chemotherapy is associated with serotonin release in the acute phase. There is no serotonin release during the delayed phase. Thus the use of 5HT3 antagonists for delayed-phase nausea and vomiting would appear questionable.

[Anesthesia in the management of pyloric stenosis. Evaluation of the combination of propofol-halogenated anesthetics]

This study was aimed at evaluating haemodynamic changes during an anaesthetic sequence for full stomach, using propofol as induction agent and volatile anaesthetics for maintenance of anaesthesia in infants scheduled for surgical cure of hypertrophic pyloric stenosis. After correction of preoperative blood electrolyte and metabolic disturbances with appropriate i.v. hydrating solutions, anaesthesia was induced with propofol and suxamethonium. Infants were divided in two groups according to the volatile anaesthetic agent used for maintenance of anaesthesia after tracheal intubation: halothane (n = 16) or isoflurane (n = 15). The two groups were identical regarding weight (4.28 +/- 0.6 vs 4.14 +/- 0.76 kg), age (1.6 +/- 0.9 vs 1.5 +/- 0.6 months), preinduction heart rate (155 +/- 22 vs 151 +/- 22 b.min-1) and systolic-diastolic arterial pressure (96 +/- 18/58 +/- 12 vs 105 +/- 16/67 +/- 15 mmHg). Propofol and suxamethonium doses were identical, 3.9 +/- 1 mg.kg-1 and 1.3 +/- 0.6 mg.kg-1 respectively in halothane group, vs 4.3 +/- 0.8 mg.kg-1 and 1.3 +/- 0.4 mg.kg-1 in isoflurane group. Heart rate did not change after induction of anaesthesia, while arterial blood pressure decreased significantly (p < 0.001). However, blood pressure remained within the normal range for age throughout the procedure. Mean duration of surgery was shorter in halothane group (64 +/- 16 vs 79 +/- 17 min, p < 0.05), however time-interval from the end of surgery to tracheal extubation (12 +/- 6 vs 15 +/- 8 min) was short and identical in the two groups.(ABSTRACT TRUNCATED AT 250 WORDS)