The Negative Effects of Patient Controlled Sedation Using Midazolam for Cataract Surgery under Retrobulbar Block / 대한마취과학회지

BACKGROUND: Careful sedation is needed for cataract operation that requires absolute cooperation of elderly patients. Patient-controlled sedation (PCS) allows patients themselves change the dose of sedatives along with their need. The goal of this study was to find out midazolam PCS could achieve an adequate sedation without complications during cataract surgery and the differences of patients who needed PCS or not. METHODS: PCS with midazolam was applied to 33 patients undergoing cataract surgery using retrobulbar block (midazolam, bolus 0.5 mg, lock out interval 3 minutes, 1 hour limit 4.5 mg). PCS pump was given to patients 30 min before retrobular block. And patients themselves decided to use or not to use PCS after full explanation on PCS. Sedation score, visual analogue scale of anxiety, cognitive function, side effects and satisfaction of PCS were measured. RESULTS: PCS users were 22 (67%). Mean midazolam dosage of PCS users was 2.03 mg. Preoperative and intraoperative anxiety score were 40.2 mm and 13.0 mm in PCS users and 15.5 mm and 21.8 mm in non-users. The difference between PCS users and non-users was only preoperative anxiety levels. Age, sex, weight, education levels, previous cataract surgery, preoperative desired sedation levels did not influence on the PCS using. There was positive correlation of midazolam doses with only preoperative anxiety levels. 76% of surgeons and 85% of patients were satisfied with PCS but 7 patients showed involuntary movement. Cognitive functions and discharge time were not influenced by PCS. CONCLUSIONS: Although patients and surgeons were satisfied with the midazolam PCS, 33% of patients did not need PCS and deep sedation with involuntary movement that could bring surgical complications was resulted in some PCS users. We conclude that PCS for cataract surgery would be safer when it is administered under careful supervision of anesthesiologist.

The Efficacy of Patient-Controlled Sedation and Analgesia in Patients Undergoing Endoscopic Sinus Surgery / 대한마취과학회지

BACKGROUND: Patients receiving surgery under local anesthesia might feel anxiety during surgery and suffer pain due to the insufficiency of local anesthesia. The purpose of this study was to evaluate the efficacy and side effects of patient-controlled sedation and analgesia in patients undergoing endoscopic sinus surgery (ESS). METHODS: We studied 63 adult patients. A mixture of 400 mg of propofol and 200microgram of fentanyl (total 44 ml) was infused to the patient at a rate of 10 ml/hr using a PCA device. The lock-out time was 1 minute and the bolus dose was 1 ml. During surgery, we monitored vital signs and sedation state. At the end of surgery, we assessed the degree of satisfaction about pain and anxiety relieving effects by using a questionnaire with a 1 to 10 scale. RESULTS: About 90% of patients were wide awake during surgery, others were drowsy or intermittently sleeping. About 95% of the patients were satisfied with anxiety relief (more than a score of 8) and 84% were satisfied with pain relief in painful episodes (more than a score of 8). Vital signs were within normal limits. The oxygen saturation was maintained above 94% during surgery, except three patients whose oxygen saturation was 92% for short while. Twenty-two percent of the patients complained of pain at their drug infusion sites. CONCLUSIONS: We concluded that patient-controlled sedation and analgesia using the mixture of fentanyl and propofol might be a good way to relieve patient's anxiety and pain without respiratory depression and excessive sedation for those undergoing ESS under local anesthesia.

Patient Controlled Sedation Using Propofol during Regional Anesthesia for Cesarean Section / 대한마취과학회지

BACKGROUND: During regional anesthesia for a cesarean section, adverse effects such as nausea and/or vomiting (N&V), visceral pain and shivering are common complications. A subhypnotic dose of propofol has been known to have an antiemetic effect perioperatively. Patient controlled sedation (PCS) using propofol might be a solution for emesis and other adverse effects occurring during regional anesthesia in cesarean deliveries. METHODS: One hundred ten parturients scheduled for elective cesarean section were randomly divided into two groups: PCS-spinal (n = 55) and PCS-epidural (n = 55). Spinal anesthesia was performed with 0.5% bupivacaine 10 mg and 10 microgram of fentanyl. Epidural anesthesia was performed with 2% lidocaine 25 ml + 100 microgram of fentanyl + 0.1 mg of epinephrine + 1.5 ml of 8.4% sodium bicarbonate in the PCS-epidural group. After delivery, PCS with propofol was applied to the patients in both groups (bolus dose: 30 mg, lock-out time: 3 min, no background infusion). We investigated incidences of adverse effects such as N&V, hypotension, intraoperative visceral pain, and shivering during the operation. We also assessed sedation scores (Grade 1 - 5) in the patients of both groups. RESULTS: There was no difference in sensory levels between the groups. Although more patients in the PCS-epidural group complained of N&V (3.6%:20%, P = 0.018) and shivering (0%:14.5%, P = 0.036) in the PACU, there were no differences intraoperative adverse effects between both groups. The sedation score did not differ between the groups. CONCLUSIONS: With PCS using propofol, adverse effects during cesarean section under both regional anesthesias are negligible.