Kari Korttila

Randomized comparison of recovery after propofol-nitrous oxide versus thiopentone-isoflurane-nitrous oxide anaesthesia in patients undergoing ambulatory surgery

A randomized, prospective study was performed to compare recovery characteristics in 41 ASA physical status I‐II patients scheduled for ambulatory surgery with either propofol or thiopentone‐isoflurane anaesthesia. Particular attention was focused on the recovery time needed to meet discharge criteria. The propofol group received propofol 2 mg · kg‐1 for induction followed by propofol infusion (6–9 mg · kg‐1 · h‐1) 1 min after intubation. The thiopentone‐isoflurane group received thiopentone 4 mg · kg‐1 for induction followed by isoflurane (0.5–2%) 1 min after endotracheal intubation. Other drugs administered during or after anaesthesia were similar between the groups. The propofol group had significantly (P<0.05) faster clinical recovery than the isoflurane group with respect to times to response to commands, eye opening, orientation, ability to stand and void, tolerance to oral fluids, “home‐readiness”, and recovery of perceptual speed. Patients in the propofol group had significantly less (P<0.05) emesis than the patients given isoflurane. We conclude that in patients undergoing ambulatory surgery propofol infusion is preferable to thiopentoneisoflurane anaesthesia, because it may allow faster discharge home.

Epileptiform Electroencephalogram during Mask Induction of Anesthesia with Sevoflurane

BACKGROUND Sevoflurane is suggested as a suitable anesthetic agent for mask induction in adults. The authors recently found that hyperventilation during sevoflurane-nitrous oxide-oxygen mask induction is associated with cardiovascular hyperdynamic response. We tested the hypothesis that the hyperdynamic response can be explained by electroencephalography (EEG) findings. METHODS Thirty women were randomly allocated to receive sevoflurane-nitrous oxygen-oxygen mask induction using a single-breath method, followed by either spontaneous breathing (n = 15) or controlled hyperventilation (n = 15) for 6 min. EEG was recorded. Blood pressure and heart rate were recorded at 1-min intervals. RESULTS Epileptiform EEG activity (spikes or polyspikes) was seen in all patients with controlled hyperventilation, and in seven patients with spontaneous breathing (P < 0.01). Jerking movements were seen in three patients with controlled hyperventilation. In the controlled hyperventilation group, heart rate increased 54% from baseline at 4 min after induction (P < 0.001). Mean arterial pressure increased 17% (P < 0.05), peaking at 3 min. In the spontaneous breathing group, heart rate showed no change, and mean arterial pressure decreased by 14% (P < 0.01) at 6 min. Heart rate and mean arterial pressure differed significantly between the groups from 2 min after beginning of the induction to the end of the trial. An increase in heart rate of more than 30% from baseline always was associated with epileptiform EEG activity. CONCLUSIONS Sevoflurane mask induction elicits epileptiform EEG patterns. These are associated with an increase in heart rate in patients with controlled hyperventilation and also during spontaneous breathing of sevoflurane.

Recovery profile after desflurane with or without ondansetron compared with propofol in patients undergoing outpatient gynecological laparoscopy

We studied the effect of combining prophylactic ondansetron (4 mg intravenously [IV]) to desflurane-based anesthesia in 90 ASA grade I or II women undergoing outpatient gynecological laparoscopy. Recovery after anesthesia, with special focus on postoperative nausea and vomiting (PONV), was assessed. Control groups received a similar desflurane anesthetic (placebo) or a propofol-infusion-based (active control) anesthetic. The study design was randomized, controlled, and double-blind (regarding ondansetron) and single-blind (regarding the anesthetic technique). Early recovery (eye opening, orientation, following commands, sitting) was similar in the three groups. However, overall home readiness (toleration of oral fluids, walking, pain tolerable by oral analgesics, no or only mild nausea) was achieved faster in the desflurane group receiving ondansetron (109 [21-937] min, P < 0.01) and in the propofol group (110 [33-642] min, P < 0.001) when compared to the desflurane only group (372 [45-723] min) (median [range]). The total incidence of PONV in the desflurane-only group was 80% (P < 0.01), compared to 40% and 20% in the desflurane group receiving ondansetron and the propofol group, respectively. The postoperative antiemetic requirements were consistently and significantly (P < 0.01) higher in the desflurane-only group compared to the other two groups. Postoperative sedation, analgesic requirements, and psychomotor recovery (assessed by the Maddox Wing and the Digit Symbol Substitution Tests) were similar in the three groups. Our results suggest that in order to achieve a propofol-like recovery profile in patients with a high likelihood of PONV, desflurane should be combined with a potent antiemetic (e.g., ondansetron). (Anesth Analg 1996;82:533-8)

Awakening, clinical recovery, and psychomotor effects after desflurane and propofol anesthesia.

We compared postanesthetic and residual recovery of desflurane versus propofol anesthesia.Twenty volunteers were anesthetized for 1 h at 1-wk intervals with either propofol (induction) plus desflurane (1.25 minimum alveolar anesthetic concentration) in O2 (PD), propofol plus desflurane in N2 O-O2 (PDN), propofol plus propofol infusion with N2 O-O2 (PPN), or desflurane (induction) plus desflurane in O2 (DD). Awakening and clinical recovery were measured. Psychomotor skills (attention, coordination, reactive skills, and memory) were tested before and 1, 3, 5, and 7 h after anesthesia. Awakening was fastest in Group PDN. At 1 h after anesthesia, the subjects given desflurane for maintenance (PD, PDN, and DD) performed significantly (P < 0.05-0.01) better in several psychomotor tests compared with those whose anesthesia was maintained with propofol (PPN). However, subjects met criteria for home readiness as fast after PPN as after PDN anesthesia (mean times +/- SE until fitness for discharge were 126 +/- 20, 81 +/- 14, 70 +/- 7, and 106 +/- 14 min after PD, PDN, PPN, and DD, respectively). Awakening and early psychomotor recovery for as long as 1 h after anesthesia is faster after desflurane than after propofol, but there was no difference in time to home readiness or in residual effects thereafter between propofol and desflurane with N2 O in O2. (Anesth Analg 1996;83:721-5)

Clinical recovery and psychomotor function after brief anesthesia with propofol or thiopental

Propofol, the new intravenous anesthetic agent, is generally used in outpatient anesthesia with expectations of fast recovery. We assessed recovery from anesthesia in a double-blind, crossover, controlled manner in 12 healthy volunteers using clinical tests during the first hour and several psychomotor tests 0.5, 1, 3, 5, and 7 h after brief anesthesia with propofol (2.5 mg/kg and 1.0 mg/kg 3 min later) or thiopental (5.0 mg/kg and 2.0 mg/kg 3 min later). Subjects were able to respond to command, sit, and stand steadily significantly faster (P less than 0.05) after propofol (time until standing steadily 33 +/- 7 min; mean +/- SD) when compared to thiopental anesthesia (time until standing steadily 62 +/- 29 min; mean +/- SD). Psychomotor performance remained significantly worse (P less than 0.05 to P less than 0.001) compared to control for 1 h after propofol and for 5 h after thiopental anesthesia. We conclude that the rapid and complete recovery makes propofol a suitable anesthetic for patients undergoing brief ambulatory surgery.

A double-blinded, randomized comparison of intrathecal and epidural morphine for elective cesarean delivery.

We randomized 150 parturients into a double-blinded trial to receive intrathecal (IT) 100 &mgr;g (IT 100 group) or 200 &mgr;g (IT 200 group) or epidural 3 mg (Epidural group) of morphine for elective cesarean delivery with a combined spinal/epidural technique. The patients additionally received ketoprofen 300 mg/d. Postoperative pain relief and side effects were registered every 3 h up to 24 h, and all patients were interviewed on the first postoperative day. Pain control was equally good, but the parturients in the IT 100 group requested rescue analgesics more often compared with the other groups (P < 0.05). Itching was a common complaint and was reported by 74% of the parturients in the Epidural group and 65% and 91% in the IT 100 and IT 200 groups, respectively (P < 0.01). Medication for itching was requested by 44%, 24%, and 45% of the patients, respectively (P < 0.05). There was no difference in postoperative nausea or vomiting. The pain relief was perceived as good by >90% of the patients in all groups. In conclusion, because of the decreased incidence of and lesser requirements of medication for itching, IT morphine 100 &mgr;g with ketoprofen is recommended in cesarean deliveries. Rescue analgesics nevertheless need to be prescribed.

Recovery and Simulated Driving after Intravenous Anesthesia with Thiopental, Methohexital, Propanidid, or Alphadione

Recovery from anesthesia was assessed in a double-blind manner in 40 healthy volunteer students after intravenous anesthesia with thiopental (6.0 mg/kg), methohexital (2.0 mg/kg), propanidid (6.6 mg/kg), or alphadione (Althesin), 85 ul/kg using a driving simulator 2, 4, 6, and 8 hours after injection of the drugs. Clinical recovery was faster after propanidid and methohexital than after thiopental or alphadione. Driving performances remained significantly (P < 0.05) worse than in a control group for 6 hours after thiopental and for 8 hours after methohexital, and reaction times 8 hours after thiopental remained worse than in the control subjects. After alphadione driving skills were impaired at 6 hours only. Propanidid produced no impairment in driving skills at any time during the experiment. It is concluded that after the doses used in this study patients should not drive or operate machinery for at least 2 hours after propanidid and for at least 8 hours after alphadione. After methohexital and thiopental patients should probably not drive for 24 hours because of the severity of the disturbances at 8 hours.

A comparison of selective spinal anesthesia with hyperbaric bupivacaine and general anesthesia with desflurane for outpatient knee arthroscopy

In this randomized and controlled trial, 64 adult ambulatory knee arthroscopy patients received either selective spinal anesthesia (SSA) with 4 mg of hyperbaric bupivacaine or general anesthesia (GA) with desflurane. We conducted the study to determine whether SSA with small-dose bupivacaine provides equal fast-tracking possibilities, a shorter stay in the postanesthesia care unit, and earlier discharge home compared with GA with desflurane. Patients with a high risk for postoperative nausea and vomiting received prophylaxis in the GA group. No difference was seen in the fast-tracking possibilities or time in the postanesthesia care unit between the groups. Home readiness was achieved after 114 (31–174) and 129 (28–245) min (NS) in the SSA and GA groups, respectively. In the hospital, the pain scores were significantly (P < 0.001) lower in the SSA group compared with the GA group and the need for postoperative opioids was significantly (P = 0.008) larger after GA. The incidence of postoperative nausea and vomiting was 0% versus 19% in the SSA and GA groups (P = 0.024), respectively. We conclude that for outpatients undergoing knee arthroscopy, SSA with hyperbaric bupivacaine provides equal recovery times with less frequent side effects compared with GA with desflurane.

Sevoflurane titration using bispectral index decreases postoperative vomiting in Phase II recovery after ambulatory surgery

We tested the hypothesis that titration of sevoflurane using bispectral index (BIS) of the electroencephalogram decreases postoperative nausea and vomiting and improves recovery after outpatient gynecologic laparoscopy. After propofol induction, anesthesia was maintained in all patients with sevoflurane in 65% nitrous oxide and oxygen. In the BIS-Titrated group (n = 32), sevoflurane was titrated to maintain the BIS between 50 and 60 during surgery. In the Control group (n = 30), sevoflurane was adjusted to keep hemodynamic variables within 25% of control values. The severity of pain, postoperative nausea and vomiting, and recovery variables were recorded. In the Control group, 30% of the patients had BIS <40 during surgery (versus 0 in the BIS-Titrated group). Orientation and ability to drink were achieved earlier in the BIS group (P < 0.05). At 30 min after cessation of nitrous oxide, patients in the BIS group performed better in the psychomotor recovery test (P < 0.01). In Phase II recovery room, these patients had significantly less vomiting than the patients in the Control group (16% versus 40% of the patients, respectively, P < 0.05). No differences were found in times to achieve home readiness.

Comparison of intramuscular dexmedetomidine and midazolam premedication for elective abdominal hysterectomy

The purpose of this study was to compare the periop-erative effects of the intramuscular (IM) α2 agonist, dexmedetomidine (DEX), and midazolam (MID) premedication. The study comprised 192 women (64 per group) scheduled for abdominal hysterectomy. The doses of the study drugs were chosen to obtain equal sedative effects. The three groups were: 1) IM DEX (2.5 μ/kg) and intravenous (IV) placebo (DexPla group), 2) IM DEX and IV fentanyl (FENT) (1.5 μg/kg) (DexFent group), and 3) IM MID (0.08 mg/kg) and IV FENT (MidFent group). IM drugs were administered 45–90 min before induction of anesthesia. Preoperative sedation and anxiolysis after DEX was comparable to that after MID. The maximum arterial blood pressure response to endotracheal intubation was blunted in the DexFent group, while in the two other groups blood pressure increased 30–34 mm Hg after endotracheal intubation. The mean isoflurane concentration during surgery was 0.14% in the DexFent group, 0.24% in the DexPla group, and 0.34% in the MidFent group (P < 0.001). During surgery, bradycardia (heart rate < 40 bpm) was observed in 6.2% of DEX patients, and no MID patients, whereas postoperatively 14.1% of DEX patients and 1.6% of MID patients had bradycardia. Fewer patients suffered from postoperative shivering after DEX (10%) than after MID (52%). We conclude that DEX has many desirable effects, but side effects such as bradycardia may limit its routine use in ASA physical status 111 patients.