Larry L. Duffy

Dexamethasone facilitates discharge after outpatient anorectal surgery.

Corticosteroids can decrease pain and postoperative nausea and vomiting after ambulatory surgery. Therefore, we designed a study to evaluate if the routine use of dexamethasone would facilitate the early recovery process after anorectal surgery. A secondary aim of the study was to determine if dexamethasone would increase the incidence of postoperative wound complications. Eighty adult outpatients undergoing anorectal surgery with a standardized monitored anesthesia care technique were randomly assigned to receive either dexamethasone 4 mg IV or an equal volume of saline before the start of surgery. All patients were premedicated with midazolam 2 mg IV and received ketorolac 30 mg IV as a preemptive analgesic. A propofol infusion, 50 &mgr;g · kg−1 · min−1 IV, was initiated and subsequently titrated to maintain an observer’s assessment of alertness/sedation score of 2 or 3 (with 5 = awake/alert to 1 = asleep). Fentanyl 25 &mgr;g IV was administered 3–5 min before infiltrating the surgical field with a 30-mL local anesthetic mixture containing 15 mL of lidocaine 1% and 15 mL of bupivacaine 0.25% (with epinephrine 1:200,000 and sodium bicarbonate 3 mL). All patients were fast-tracked directly from the operating room to the step-down recovery area. Even though the incidences of postoperative pain and postoperative nausea and vomiting were small in both treatment groups, the time to “home readiness” was significantly shorter in the dexamethasone group. Importantly, there was no increase in the incidence of wound infections (8% vs 12%) or hematoma formation (3% vs 5%) in the dexamethasone (versus saline) group. We conclude that the administration of dexamethasone, 4 mg IV, shortened the time to home readiness without increasing the incidence of postoperative wound infections in a high-risk outpatient population undergoing anorectal surgery. IMPLICATIONS A single dose of dexamethasone (4 mg IV) decreased the time to “home readiness” without increasing the incidence of postoperative wound complications in an outpatient population undergoing anorectal surgery.

Effects of Prophylactic Nalmefene on the Incidence of Morphine-related Side Effects in Patients Receiving Intravenous Patient-controlled Analgesia

BACKGROUND Opioid-related side effects associated with intravenous patient-controlled analgesia can be reduced by a low-dose naloxone infusion. The influence of nalmefene, a pure opioid antagonist with a longer duration of action, on opioid-related side effects has not been evaluated. This study was designed to determine the dose-response relation for nalmefene for the prevention of morphine-related side effects in patients receiving intravenous patient-controlled analgesia. METHODS One hundred twenty women undergoing lower abdominal surgery were enrolled in the study. General anesthesia was induced using thiopental and rocuronium and maintained with desflurane, nitrous oxide, and fentanyl or sufentanil. All patients received neostigmine and glycopyrrolate to reverse residual neuromuscular blockade. No prophylactic antiemetics were administered. At the end of surgery, patients were randomized to receive saline, 15 microg nalmefene, or 25 microg nalmefene intravenously. The need for antiemetic and antipruritic drugs and the total consumption of morphine during the 24-h study were recorded. The incidences of postoperative nausea, vomiting, pruritus, and pain were recorded 30 min after patients were admitted to the postanesthesia care unit. In addition, patient remembrance of these side effects was noted at 24 h after operation. RESULTS The need for antiemetic and antipruritic medications during the 24-h study period was significantly lower in the patients receiving nahmefene compared with those receiving placebo. However, the need to treat side effects was similar in the two nahmefene groups. Prophylactic administration of nalmefene reduced the patients remembrance of nausea and itching as assessed 24 h after operation. Although the total consumption of morphine during the 24-h study period was similar in the three groups, retrospectively patients who received nalmefene characterized their pain as less severe in the previous 24 h. CONCLUSION Compared with placebo, prophylactic administration of nalmefene significantly decreased the need for antiemetics and antipruritic medications in patients receiving intravenous patient-controlled analgesia with morphine.

Comparison of Adenosine and Remifentanil Infusions as Adjuvants to Desflurane Anesthesia

BACKGROUND Because adenosine has been alleged to produce both anesthetic and analgesic sparing effects, a randomized, double-blinded study was designed to compare the perioperative effects of adenosine and remifentanil when administered as intravenous adjuvants during general anesthesia for major gynecologic procedures. METHODS Thirty-two women were assigned randomly to one of two drug treatment groups. After premedication with 0.04 mg/kg intravenous midazolam, anesthesia was induced with 2 micro/kg intravenous fentanyl, 1.5 mg/kg intravenous propofol, and 0.6 mg/kg intravenous rocuronium, and maintained with desflurane, 2%, and nitrous oxide, 65%, in oxygen. Before skin incision, an infusion of either remifentanil (0.02 microg x kg(-1) x min(-1)) or adenosine (25 microg x kg(-1) x min(-1)) was started and subsequently titrated to maintain systolic blood pressure, heart rate, or both within 10-15% of the preincision values. RESULTS Adenosine and remifentanil infusions were effective anesthetic adjuvants during lower abdominal surgery. Use of adenosine (mean +/- SEM, 166+/-17 microg x kg(-1) x min(-1)) was associated with a significantly greater decrease in systolic blood pressure and higher heart rate values compared with remifentanil (mean +/- SEM, 0.2+/-0.03 microg kg(-1) x min(-1)). Total postoperative opioid analgesic use was 45% and 27% lower in the adenosine group at 0-2 h and 2-24 h after surgery, respectively. CONCLUSIONS Adjunctive use of a variable-rate infusion of adenosine during desflurane-nitrous oxide anesthesia was associated with acceptable hemodynamic stability during the intraoperative period. Compared with remifentanil, intraoperative use of adenosine was associated with a decreased requirement for opioid analgesics during the first 24 h after operation.

The effect of ketorolac on recovery after anorectal surgery: intravenous versus local administration.

T he role of ketorolac in facilitating the recovery process after ambulatory surgery is controversial. Ketorolac, a nonsteroid antiinflammatory drug (NSAID), produces pain relief with less respiratory depression, nausea, and vomiting than opioid analgesics (1). When used as an alternative to fentanyl in outpatients undergoing laparoscopy (2), ketorolac was associated with comparable postoperative analgesia and shorter discharge times. Additionally, the combination of ketorolac and local anesthesia provided superior postoperative analgesia than either drug alone in patients undergoing knee arthroscopy procedures (3,4). Although IV ketorolac has well known opioidsparing properties (2–4) and even possible anestheticsparing qualities (5), the injection of ketorolac at the surgical site has been reported to possess varying degrees of analgesic activity (6–8). When ketorolac was administered “locally” to patients undergoing hemorrhoidectomy (6) and inguinal hernia repair (7), it decreased the postoperative pain scores and enhanced patient comfort compared with systemic morphine and IV ketorolac, respectively. However, in patients undergoing breast surgery (8), the analgesic effect of ketorolac administered at the surgical site was no more effective than IV ketorolac. We hypothesized that the administration of ketorolac at the surgical site (local) would provide more effective postoperative analgesia than IV administration during surgery performed under local anesthesia with sedation as part of a monitored anesthesia care technique. Specifically, this study was designed to determine if a single dose of ketorolac could facilitate the recovery process after anorectal surgical procedures. Methods

Fast-tracking after immersion lithotripsy: general anesthesia versus monitored anesthesia care.

UNLABELLED Both monitored anesthesia care (MAC) and general anesthesia (GA) offer advantages over epidural anesthesia for immersion lithotripsy. We compared propofol-based MAC and desflurane-based GA techniques for outpatient lithotripsy. After receiving midazolam 2 mg IV, 100 subjects were randomly assigned to one of two anesthetic treatment groups. In the MAC group, propofol 50-100 microg. kg(-1). min(-1) IV was titrated to maintain an observers assessment of alertness/sedation score of 2-3 (5 = awake/alert to 1 = asleep). Remifentanil 0.05 microg.kg(-1). min(-1) IV supplemented with 0.125 microg/kg IV boluses, was administered for pain control. In the GA group, anesthesia was induced with propofol 1.5 mg/kg IV and remifentanil 0.125 microg/kg IV and maintained with desflurane (2%-4% inspired) and nitrous oxide (60%). Tachypnea (respiratory rate >20 breaths/min) was treated with remifentanil 0.125 microg/kg IV boluses. In the GA group, droperidol (0.625 mg IV) was administered as a prophylactic antiemetic. Recovery times and postoperative side effects were assessed up to 24 h after the procedure. Compared with MAC, the use of GA reduced the opioid requirement and decreased movements and episodes of desaturation (<90%) during the procedure. Although the GA group took longer to return to an observers assessment of alertness/sedation score of 5, discharge times were similar in both groups. We conclude that GA can provide better conditions for outpatient immersion lithotripsy than MAC sedation without delaying discharge. IMPLICATIONS A desflurane-based general anesthetic technique using the cuffed oropharyngeal airway device was found to be a highly acceptable alternative to propofol-based monitored anesthesia care sedation for outpatient immersion lithotripsy.

Spontaneous Recovery Profile of Rapacuronium During Desflurane, Sevoflurane, or Propofol Anesthesia for Outpatient Laparoscopy

UNLABELLED We evaluated the spontaneous recovery characteristics of rapacuronium during desflurane-, sevoflurane-, or propofol-based anesthesia in 51 consenting women undergoing laparoscopic tubal ligation procedures. After the induction of the anesthesia with standardized doses of propofol and fentanyl, 1.5 mg/kg IV rapacuronium was administered to facilitate tracheal intubation. Patients were randomized to receive either 1 minimum alveolar anesthetic concentration of desflurane, 1 minimum alveolar concentration of sevoflurane, or 100 microg. kg(-1). min(-1) propofol infusion in combination with 66% nitrous oxide in oxygen for maintenance of anesthesia. Neuromuscular blockade was monitored at the wrist by using electromyography. The degree of maximum blockade and the times for first twitch recovery (T(1)) to 5%, 25%, 50%, 75%, and 90%, as well as the recovery index, were similar in all three anesthetic groups. However, recovery times for the train-of-four ratio to achieve 0.7 and 0.8 were significantly longer with desflurane (44.4 +/- 18.9 and 53.5 +/- 22.4 min) and sevoflurane (44.8 +/- 15.1 and 53.2 +/- 15.8 min) compared with propofol (31.8 +/- 5.3 and 36.5 +/- 6.5 min). Eight patients (16%) required a maintenance dose of 0.5 mg/kg rapacuronium and reversal of rapacuronium residual block occurred in three (6%) patients. We conclude that spontaneous recovery after an intubating dose of 1.5 mg/kg rapacuronium was significantly prolonged by both desflurane and sevoflurane compared with propofol-based anesthesia. Routine monitoring of neuromuscular activity is recommended even when a single bolus dose of rapacuronium is administered during ambulatory anesthesia. IMPLICATIONS When administered for laparoscopic surgery, the duration of action of an intubating dose of rapacuronium was prolonged 40%-50% by desflurane and sevoflurane, respectively, (versus propofol). Monitoring recovery of neuromuscular blockade produced by rapacuronium is particularly important when desflurane or sevoflurane is administered to ensure that an adequate recovery (train-of-four > or = 0.8) is achieved by the end of anesthesia.