Propofol infusion for sedation in outpatient oral surgery

An infusion of propofol was compared with intravenous boluses of diazepam as sedation for minor oral surgery under local anaesthesia in 12 healthy patients who had elective bilateral surgical extraction of lower third molars; the patients served as their own controls. Plasma catecholamine, vasopressin and cortisol concentrations were determined from repeated blood samples. The total administered dose of propofol was 3.93 (SD 1.34) mg/kg and of diazepam 0.28 (SD 0.07) mg/kg. No cardiovascular depression or airway problems occurred. Other side effects were also rare but some discomfort on injection was frequent with propofol. Recovery times were faster after propofol than after diazepam as assessed by the Maddox wing and visual analogue scales. Propofol also provided better amnesia compared to diazepam at the time of the extraction of the teeth. Eight of the 12 patients subjectively preferred propofol sedation. There was no hormonal stress response in either group.     

The use of oral sedatives in dental care

Oral administration of tranquillizing and anxiety-suppressing drugs has long been the commonest method of achieving light sedation. The benzodiazepines are the drugs of first choice. Benzodiazepines given orally may be indicated to avoid 'treatment stress', alleviate mild anxiety before dental treatment, and facilitate sleep on the night before the treatment. Furthermore, they could be used for the dental treatment of medically poor risk patients, particularly those with cardiovascular disease. The drug can be given either in a fractionated dose or a single dose. The recommended doses for diazepam vary from 0.1–0.8 mg/kg body weight, depending on age, with higher doses in children and lower doses in elderly patients. Few side effects are reported.     

Premedication with oral and rectal diazepam

It has been postulated that esophageal retention of diazepam tablets is a problem of clinical significance, and that rectal administration is an advantageous alternative. To test this hypothesis, 100 patients were randomly allocated to premedication with either 15 mg diazepam orally or 10 mg diazepam as a rectal solution. A double dummy technique was used. A sedative effect was seen in 23 (50%) of the patients premedicated by mouth (O-group), but only in eight (20%) of those premedicated rectally (R-group) (P less than 0.05). Four patients (9%) in the O-group and seven (18%) in the R-group were unacceptably anxious before induction (n.s.). The plasma concentrations in the tablet group were nearly twice the concentrations found in the rectal-solution group, but no correlation between premedication effect and plasma concentration was found. Timing of premedication was very inaccurate, and this favored oral administration because of a more prolonged effect. No evidence of persistent esophageal retention was found.     

Intravenous narcotics for premedication in outpatient anaesthesia

One hundred adult female patients scheduled for outpatient laparoscopic procedures were studied. Each patient received intravenous premedication about 30 min before induction of anaesthesia. The premedications were given in a double-blind random order and were either a placebo, morphine (0.04 mg/kg), meperidine (0.35 mg/kg), fentanyl (0.75 microgram/kg) or sufentanil (0.15 microgram/kg). All patients received a standard anaesthetic regimen. Transient light-headedness was common following narcotic injections. Overall, sufentanil was superior to the placebo and to other narcotics in its ability to reduce preoperative anxiety and to provide more satisfactory induction, maintenance and recovery from anaesthesia. The incidence of postoperative nausea, vomiting and other side effects was not higher and discharge times were not longer after sufentanil compared to the placebo group. Complete recovery as assessed by telephone interview 24-48 h after the operation revealed no difference between the sufentanil and the other groups. The results of this study indicate that intravenous short-acting narcotics like fentanyl or sufentanil should be considered as an alternative premedicant for anxious patients who are scheduled for outpatient surgery.     

Comparison of triazolam v. diazepam as an oral preanaesthetic medication for outpatient paediatric surgery

Diazepam, in combination with pethidine and atropine, has proved to be an effective oral pre-anaesthetic medication for paediatric outpatient surgery. Triazolam is a benzodiazepine with a short half-life and rapid oral absorption, and causes amnesia and sedation. The results of a prospective, randomized, double-blind study substituting triazolam for diazepam in this regimen are described. One hundred and nineteen healthy paediatric outpatients older than 1 year of age were randomized to receive either our routine oral outpatient premedication (pethidine 1.5 mg·kg^-1, diazepam 0.15 mg·kg^-1 and atropine 0.02 mg·kg^-1), an oral premedicant where triazolam (0.005 mg·kg^-1) was substituted for diazepam or an oral premedicant containing pethidine and atropine only. Children given triazolam had a more rapid onset of pre-anaesthetic medication effect (change in state of consciousness) compared with patients in the other two groups (P < 0.01). Patients receiving traizolam showed more evidence of sedation within 45 min of receiving the oral premedication (P < 0.003). There were no other differences between the three groups.     

Plasma concentrations following repeated rectal or intravenous administration of paracetamol after heart surgery

BACKGROUND: Paracetamol is commonly used for post-operative pain management in combination with more potent analgesics. The best route of paracetamol administration after major surgery, when oral intake may not be optimal, is not known. Our primary purpose was to study plasma concentrations after the 1st and 4th dose of 1 g of paracetamol given either rectally or intravenously (i.v.) after major surgery. METHODS: In this prospective, randomized study, 48 patients undergoing heart surgery were randomized upon arrival to the intensive care unit (ICU) to receive paracetamol every 6th hour either as suppositories or intravenous injections. In half the patients (n = 24), blood samples for paracetamol concentration were obtained before and 20, 40 and 80 min after the first dose. In the other patients (n = 24), additional samples were taken prior to, and at 20, 40, 80 min and 4 and 6 h after, the 4th dose. RESULTS: Plasma paracetamol concentration peaked (95 +/- 36 micromol/l) within 40 min after initial i.v. administration but did not increase within 80 min after the 1st suppository. Plasma concentration before the 4th dose was 74 +/- 51 and 50 +/- 27 in the rectal and i.v. groups, respectively. Paracetamol concentration peaked 20 min after the 4th dose for the i.v. patients (210 +/- 84 micromol/l) and declined to 99 +/- 27 micromol/l at 80 min as compared with the rectal patients 69 +/- 44 to 77 +/- 48 micromol/l. CONCLUSION: Both time course and peak plasma concentrations of paracetamol given rectally differ from the one seen after intravenous administration. The clinical impact of these differences needs further investigation.     

Behavioural changes and children's memories after intravenous, inhalation and rectal induction of anaesthesia

Ninety two-to-seven-year-old children admitted for routine day case ENT operations were randomly allocated to have either intravenous thiopentone (group I), halothane inhalation (group II) or rectal methohexitone (group III) for anaesthesia induction. Using a postoperative questionnaire, the parents evaluated the changes in the child's behaviour one day, one week and one month after the operation. Problematic changes were detected in 17 (59%) children in group I, 14 (50%) in group II and 17 (58%) in group III (NS). Although the children in group II behaved most calmly during the induction they had significantly more negative memories of the induction of anaesthesia (six children in group II vs two in group I and one in group III) and of the hospital in general (17 in group II vs 11 in group I and eight in group III) than children in the other groups. Judging from memories of young children, intravenous and rectal inductions are less distressing to them than inhalational induction.     

Comparison of Rectal Diazepam and Subcutaneous Morphine-Scopolamine Administration for Outpatient Sedation in Minor Oral Surgery

In a randomized cross-over study on sedation in outpatient oral surgery, subcutaneous administration of morphine-scopolamine was compared with rectal administration of diazepam. The mean dose of morphine was 0.13 mg kg-1 (range 0.13-0.24) and of diazepam 0.57 mg kg-1 (range 0.50-0.71). Apprehension, the determining factor for patients' preference for sedation method, the recovery from sedation and the postoperative course were studied. Both methods produced the desired effects. For diazepam, the effect was scored higher by the patient than the nurse observer and for morphine-scopolamine the opposite was found. Postoperative pain and patients' preference for sedation did not differ between the methods and the determining factor for the patients' preference for sedation method was the experience of stronger tranquilization. Side-effects such as prolonged recovery, nausea, dizziness, and dysphoria were frequent during the postoperative course after the morphine-scopolamine sedation but were not seen during diazepam sedation. Thus, rectal administration of diazepam should be preferred to morphine and scopolamine for sedation in minor oral surgery performed under local anesthesia.     

Intravenous sedation for retrobulbar injection and eye surgery: Diazepam and/or propofol?

Principle goals of sedation for eye surgery are to provide patient comfort and to allow the patient to stay calm during both retrobulbar injection and surgery. Insufficient sedation may not prevent the patient from moving during retrobulbar injection, whereas very deep sedation may result in respiratory complications during surgery. The aim of the present study was to evaluates the effectiveness and suitability of a combination of diazepam and propofol for sedation for both application of retrobulbar block and subsequent elective eye surgery.
One-hundred and fifty patients were randomly allocated to receive either diazepam, propofol or a combination of both drugs before retrobulbar injection. Tolerance of retrobulbar injection and comfort during the surgical procedure were assessed by comfort scores using a nominal analogue scale between 1 (worst possible condition) and 6 (best conceivable condition). Side effects related to sedation were recorded.
The combination of diazepam and propofol resulted in the highest comfort scores for both retrobulbar block (5.3±0.3) and the surgical procedure (5.4±0.4). Diazepam alone did not produce adequate sedation for retrobulbar block (3.1±0.3), whereas comfort scores during surgery were significantly higher (5.3±0.3) compared to propofol alone (3.6±0.4). No severe side effects induced by sedation were noted in any of the study groups.
The combination of diazepam and propofol proved able to provide a reliable degree of sedation with minimal side effects for both retrobulbar block and surgery. The combination was clearly superior to the sedation induced by propofol or diazepam alone.     

Perioperative management of systemic oral anticoagulants in patients having outpatient hand surgery

Long-term oral anticoagulant therapy is frequently initiated in patients with elevated risk of venous or arterial thromboembolism. The most common indications for anticoagulation are chronic atrial fibrillation, mechanical heart valves, a history of venous thromboembolism, and hypercoagulable states. In the perioperative setting, these patients pose considerable challenges to physicians, who must weigh the thrombotic risks of therapy interruption against the bleeding risks of continuation. Development of uniform recommendations for management of anticoagulated patients undergoing elective hand surgery has proven problematic. Difficulties intrinsic to study design include a short duration of risk exposure, lack of patient uniformity, and rarity of baseline adverse events. Given the paucity of substantive evidence on which to base management decisions, physicians have long relied on clinical judgment to guide their choices. This review summarizes the available data specific to elective hand surgery and provide a general context in which evidence-based treatment decisions can be made.     

Patient-controlled sedation using propofol in day surgery

Patient-controlled sedation using propofol was studied in 30 unselected patients aged 26-72 years undergoing day case general surgical or orthopaedic procedures under local or regional anaesthesia. Using a fixed propofol dose of 0.7 mg.kg-1 body weight, the technique provided anxiolysis and sedation with few side effects and a high degree of patient satisfaction. Increasing age was significantly correlated with a deeper maximum level of sedation (p less than 0.001), indicating a need for a lower bolus dose in the higher age groups. Interpatient variability in propofol requirement was reflected in the lack of significant correlation between propofol dose and procedure duration (p = 0.095) and patient age (p = 0.72).     

A comparison of midazolam and diazepam for intravenous sedation in dentistry

In a randomised cross-over trial, midazolam, a new water soluble benzodiazepine was compared with the conventional diazepam preparation (Valium) in 34 patients aged 16-45 years who were undergoing outpatient conservation dentistry. Midazolam hydrochloride (0.17 mg/kg) was virtually free of venous complications and showed advantages over diazepam (0.32 mg/kg) in providing a faster onset of action, higher incidence of amnesia and more rapid recovery. Midazolam produced a higher incidence of respiratory side effects hiccough (17.6% compared with 2.9%), brief apnoea following induction (11.8% compared with 5.8%), and airway obstruction during maintenance (8.8% compared with 0%). These may be related to the greater potency of midazolam as suggested by the smaller total dose required. Cardiovascular changes and operating conditions were similar.     

Anesthesia technique for outpatient facial laser resurfacing

BACKGROUND AND OBJECTIVES: Multiple anesthetic approaches exist for full-face laser resurfacing. The purpose of this study was to describe an anesthesia technique based on combination of eutectic mixture local anesthetics (EMLA) and remifentanil sedation, that can be utilized by anesthesiologists in the ambulatory environment. STUDY DESIGN/MATERIALS AND METHODS: Fifty patients elected for facial laser resurfacing. All patients received topical anesthesia in full face with EMLA cream at 60 minutes (min) before laser procedure. On arrival at the operating room, intravenous (IV) sedation was administered with remifentanil (0.20 mcg/kg/minute), midazolam (1.5- 2 mg bolus IV), and propofol infusion (0.5-1 mg/kg/hour). The subsequent infusion rate of remifentanil was varied to maintain an adequate level of sedation and analgesia. Five minutes before the operation conclusion, the sedation infusion was discontinued. Patients were discharged after achieving a minimum criteria for recovery. RESULTS: Almost all the patients were successfully anesthetized by this combination technique, only four patients needed complementary anesthesia with regional nerve blockade. The mean level of sedation scored 2-3 on the Ramsay scale. The mean discharge time was 55 minutes. No complications were observed. CONCLUSIONS: The use of a combination of topical EMLA anesthesia and IV conscious sedation based on remifentanil provided an adequate depth of anesthesia for outpatient facial laser resurfacing without complications.     

Efficacy and safety of premedication with oral ketamine for day-case adenoidectomy compared with rectal diazepam/diclofenac and EMLA

BACKGROUND: Because of its pain-attenuating and sedative properties oral ketamine has been used as premedication in children and adults. We wanted to compare in children scheduled for adenoidectomy safety and efficacy of oral ketamine with a premedication that causes similar preoperative sedation and relief of pain at the venepuncture site. We also evaluated the effect of i.v. glycopyrrolate added to these combinations. METHODS: One hundred children between 10 and 15 kg of body weight scheduled for day-case adenoidectomy were randomly assigned to one of four groups: groups DG and DS received diclofenac 12.5 mg and diazepam 0.5 mg/kg rectally, EMLA cream at the venepuncture site, and placebo orally; groups KG and KS received ketamine 6.0 mg/kg orally, placebo cream at the puncture site, and placebo rectally; additionally, groups DG and KG received glycopyrrolate 5 microg/kg, and groups DS and KS received placebo intravenously. We recorded perioperatively scores (open scale 1-9) for stridor, sedation, bleeding, nausea, pain, heart rate, the need for analgesics and registered psychotomimesis and well-being at home. RESULTS: The children of the K-groups became more tearful during separation from their parents (P=0.0072). No other differences were found between the ketamine and diazepam/diclofenac groups before and after premedication until induction of anaesthesia. Oral ketamine produced unpleasant psychotomimesis in four out of 59 children. During the first 10 min postoperatively, the score for stridor was significantly higher in group KS than in the D-groups; stridor scores > or = 6 were seen in one child of the D-groups (DS) and in six children of the K-groups (n.s.), of whom three developed laryngospasm (one reintubation). Glycopyrrolate diminished salivation in all groups, but had no effect on stridor scores. Additionally, glycopyrrolate delayed the onset of eating at home. CONCLUSION: Premedication with racemic oral ketamine 6 mg/kg does not seem to be suitable for upper airway procedures. Addition of i.v. glycopyrrolate before the induction of anaesthesia significantly reduced the scores for salivation.     

The clinical pharmacokinetics of two different preparations of intrarectal Ketoprofen following spinal or local anesthesia for anal surgery

Two different preparations of commercially available suppositories containing Ketoprofen (KP) were administered to 49 patients immediately following anal surgery. The KP was prepared as either fatty suppositories (FS) or gelatin capsulated suppositories (GCS) and surgery was performed under either spinal (n=37) or local anesthesia (n=12). Similar results were observed in the kinetics of KP after both FS and GCS administration. The extent of bioavailability of the two dosage forms in the patient groups and control subjects (n=10) were essentially equal. When the pharmacokinetic parameters of KP were compared between patient groups under spinal and local anesthesia, significant differences were found in the values of the peak level (C max), peak time (T max), and terminal phase half-life (t 1/2). The C max decreased by one-half, while the T max and t 1/2 increased twice and four times, respectively, in patient operated on under spinal anesthesia compared to those operated on under local anesthesia. The absorption rate constant (Ka) following spinal anesthesia was significantly less than that following local anesthesia or that of the healthy subjects (p<0.01). A “flip-flop” phenomena could be seen in the time profiles of plasma KP concentration following spinal anesthesia.     

The use of laser in rectal surgery

Ten patients with rectal tumors were treated by surgical excision of the tumor using a CO2 laser Sharplan 733 CO2 laser, Laser Industries Ltd., Israel. The laser permitted sharp excision, evaporization, or fulguration of tissue. Good hemostasis was achieved. Anesthesia was unnecessary in cooperative, calm patients. There was no mortality or morbidity related to the procedure. In five patients with villous adenoma the tumor was resected with one recurrence as yet (followup 4-16 months). Five patients with inoperable carcinoma were treated for palliation with good results. Our preliminary results indicate that the CO2 laser can be a useful asset in rectal tumor surgery, especially in elderly, moribund patients and in the definite treatment of benign tumors of the rectum.     

Intravenous versus intraperitoneal morphine before surgery to provide postoperative pain relief

Background: Opioid receptors have been demonstrated on peripheral afferent nerves throughout the body. The aim of the present study was to compare the effects of intravenous and intraperitoneal administration of morphine with regard to pain, postoperative morphinerequirement, and recovery after major abdominal surgery, and to describe the pharmacokinetics of intraperitoneal morphine in humans.
Methods: In a double-blind manner, 30 patientsscheduled for major abdominal surgery were randomized to either 50 mg of morphine intravenously (IV) or 50 mg of morphine intraperitoneally (IP) before operation. Pain was measured on a visual analogue scale and morphine requirements were registered for 3 days. Recovery was measured as time to oral intake of food, time to flatulence and days in hospital. Plasma morphine, mor-phine-3-glucuronide, and morphine-6-glucuronide concentrations were determined during the first 4 h after morphine administration.
Results: During the first postoperative hours there was less pain at rest ( P =0.02) and on coughing ( P =0.004) in the intravenous group. The requirementof additional morphine ( P =0.016) was lower in the intravenous group during the first postoperative day. No major differences in recovery were seen. The plasma concentrations of morphine measured as area under the curve (AUC) during the first 4 h were similar, but the intravenous group showed significantly higher concentrations of the active metabolite morphine-6-glucuronide, (P=0.016), indicating a difference in pharmacokinetics after intraperitoneal compared to intravenous administration of morphine.
Conclusion: Intraperitoneal administration of 50 mg of morphine before major abdominal surgery is less efficient in reducing pain and postoperative morphine requirements than thesame amount of morphine given intravenously.     

Early bioavailability of paracetamol after oral or intravenous administration

BACKGROUND: Paracetamol is a peripherally acting analgesic commonly used in multimodal post-operative pain management to reduce the need for more potent analgesics with their unwanted side-effects. The dose and optimal galenical form for achieving analgesic concentrations is not well defined. The primary aim of this pilot project was to study the early bioavailability for two fixed doses of orally administrated paracetamol and one dose of intravenous propacetamol, all of which were given after minor surgery. METHODS: Thirty-five patients undergoing day surgery were divided into five groups, seven patients each. Groups received either 1 g of an ordinary paracetamol tablet, 2 g of an ordinary paracetamol tablet, 1 g of a bicarbonate paracetamol tablet, 2 g of a bicarbonate paracetamol tablet or 2 g intravenously of prodrug propacetamol. We studied the plasma concentration of paracetamol during the first 80 min after administration. RESULTS: Within 40 min, intravenous propacetamol gave a median plasma paracetamol concentration of 85 micromol/l (range 65-161) and decreased thereafter. After oral administration, median plasma paracetamol concentration increased with increasing dose and time, but there were huge inter-individual differences at all time points studied. At 80 min after oral paracetamol the median plasma concentrations were 36 and 129 micromol/l for the 1- and 2-g groups, respectively, with an overall range between 0 and 306 micromol/l. CONCLUSION: Oral administration of paracetamol as part of multimodal pain management immediately post-operatively resulted in a huge and unpredictable variation in plasma concentration compared with the intravenous administration.