Comparison of the Effects of Induction before and after Surgical Preparation on Neonatal Well-being in General Anesthesia for Elective Cesarean Section / 대한마취과학회지

BACKGROUND: Generally, in order to decrease the fetal exposure time from anesthetic drugs, anesthetic induction is conducted after the completion of surgical preparation in general anesthesia for cesarean section. However, this method, in decreasing the fetal exposure time from anesthetic drugs, has been regarded as also aggravating the feeling of anxiety and fear of the patients. The purpose of this research is to compare the result of anesthetic induction conducted before and after surgical preparation in relation to the well-being of the newborn. METHODS: Fifty healthy women scheduled for elective cesarean section, not in labor, with no signs of fetal distress were randomly divided into 2 groups. Group A (n = 25) started anesthetic induction after surgical preparation and group B (n = 25) started before surgical preparation. Induction to delivery (I-D) interval and uterine incision to delivery (U-D) interval were measured and for the evaluation of the neonatal outcome, blood gas analysis at umbilical vein and artery, 1 and 5 min Apgar scores, and neurobehavioral test at 15 min, 2 hr and 24 hr of age, respectively, were performed. RESULTS: There was a significant difference in the I-D interval (P < 0.05) but no significant difference in the U-D interval between the two groups. Blood gas analysis, acid-base status, Apgar score and neurologic and adaptive capacity score (NACS) all did not differ significantly between the two groups. CONCLUSIONS: From our results, the induction before surgical preparation did not seem to affect neonatal well-being significantly. Therefore, when patients without fetal distress are very anxious, anesthetic induction before surgical preparation would reduce the patient's anxiety and fear without neonatal depression in general anesthesia for cesarean section.

The Effects of Preincisional and Postincisional Low-Dose Ketamine in Addition to General Anesthesia on the Patient Controlled Analgesia for Postoperative Pain / 대한마취과학회지

BACKGROUND: Ketamine, a noncompetitive N-methyl-D-aspartate (NMDA) receptor antagonist, is known to inhibit "wind-up" and hence central hyperexcitability of dorsal horn neurons. However the results of clinical studies for its preemptive analgesic effect are controversial. The object of this study is to evaluate the effects of preincisional and postincisional low-dose ketamine on postoperative pain. METHODS: In a randomized, double-blind study, postoperative pain was assessed in 60 patients undergoing spinal fusion with general anesthesia who were allocated to three groups. Twenty patients were received 0.15 mg/kg of ketamine and the same volume of saline 5 min before and 15 min after surgical incision, respectively (group I). Patients in group II received 0.15 mg/kg of ketamine and the same volume of saline 15 min after and 5 min before surgical incision, respectively (n = 20), and in control group, patients received saline 5 min before and 15 min after surgical incision (n = 20). IV patient-controlled analgesia (PCA) with a morphine-ketorolac mixture was started in all patients at skin closure. Visual numerical scale (VNS) pain score, total analgesic consumption, and side effects were recorded at 1, 3, 6, 12, 24 and 48 h postoperatively. RESULTS: No significant intergroup differences were seen in the VNS pain scores, total analgesic consumption and incidence of side effects at 1, 3, 6, 12, 24 and 48 h postoperatively. CONCLUSIONS: This result indicates that postoperative pain cannot be decreased when ketamine in low doses is added to general anesthesia before and after surgical stimulation.

Anesthetic Management of Laparoscopic Surgery in Infant with Congenital Megacolon: A case report / 대한마취과학회지

Many benefits are reported after laparoscopy. As experience, equipment, and techniques have improved, minimally invasive laparoscopic surgery is being applied to younger children. With the advent of this new surgical approach, specific modifications become necessary in anesthetic techniques. During laparoscopy, the pneumoperitoneum performed by peritoneal insufflation of CO2 may induce intraoperative ventilatory and hemodynamic changes that complicate anesthetic management. We present a case of laparoscopic Duhamel operation in a 10-month-old infant weighing 10 kg. After induction with thiopental sodium and vecuronium, anesthesia was maintained with enflurane and 50% nitrous oxide in oxygen. Rapid hypercarbia developed about 5 minutes after introduction of pneumoperitonium, so we gave intermittent manual hyperventilation to avoid hypercarbia untill we finished the surgery. In children, CO2 absorption may be more efficient due to the physiological properties of the immature peritoneum. The functional residual capacity (FRC) is low in children. During laparoscopy, FRC is decreased further due to a variety of factors. In spite of the changes in FRC, arterial oxygenation has not been shown to deteriorate in normal infants. In our case, the changes in end-tidal CO2 tension (PETCO2) during laparoscopy did not influence the hemodynamic change. But insufflation of CO2 induced a significant increase in PETCO2, and produced a fast reaction time of PETCO2.

The Suitable Time for the Removal of Laryngeal Mask Airway / 대한마취과학회지

BACKGROUND: There were several studies for the incidence of gastroesophageal reflux associated with the laryngeal mask airway (LMA), but the results of those studies were much different from one another. This conflicting results may be due to the time of the removal of LMA, which has been usually after the arousal (when the patient can open the mouth on command). So, the authors investigated the incidence of the gastroesophageal reflux and the regurgitation of gastric contents above the upper esophageal sphincter associated with the difference of the time of the removal of LMA. METHODS: Sixty three patients scheduled for elective orthopedic surgery with a standardized general anesthetic technique were allocated randomly to Group A (n=34, LMA was removed when the rejection signs such as struggle, restlessness, swallowing and cough came out.) or Group B (n=29, LMA was removed after arousal). For the detection of reflux and regurgitation episodes during anesthesia, a pH monitoring probe was positioned in the lower esophagus and a methylene blue (50 mg) gelatine capsule was swallowed just before induction. At the end of anesthesia, the episodes of reflux and regurgitation of gastric contents were analyzed according to the pharyngeal blue staining or pH< or = 4. RESULTS: The incidence of reflux (pH< or = 4) from the time of the rejection signs to the removal of LMA and the total incidence of reflux in Group B were significantly higher than that of Group A. No patient in both group showed pharyngeal staining of methylene blue. There was no clinical evidence of aspiration of gastric contents in either group. CONCLUSION: Maintenance of LMA until the patient can open the mouth on command seems to increase the incidence of the gastroesophageal reflux.

Cardiac Arrest in Preeclamptic Patient with Unrecognized Heart Failure during Induction of General Anesthesia for Cesarean Section / 대한마취과학회지

Better medical management, together with a number of newer surgical techniques, has enable more girls with congenital heart disease to reach childbearing age. Congenital heart lesions now constitute at least half of all cases of heart disease encountered during pregnancy. Pregnancy is characterized by marked increase in stroke volume and cardic output during the antepartum period. The hemodynamic demands of pregnancy dangerously stress the impaired cardiovascular reserve. We experienced that a case of cardiac arrest in a preeclamptic patient with unrecognized heart failure during induction of the general anesthesia for cesarean section. We found out later that she had an operation because of patent ductus arteriosus at the age of 15 and then already had mitral valve regurgitation and LVH findings in the echocardiogram. We suggested that heart failure was enhanced by the hyperdynamic cardiovascular changes of normal pregnancy and further aggrevated by preeclampsia and anemia.

Effect of Preoperative Infiltration on Postoperative Analgesic Requirements in Total Abdominal Hysterectomy Patients / 대한마취과학회지

BACKGROUND: The concept of preemptive analgesia has been suggested recently as another technique in the treatment of postoperative pain. This study was undertaken to determine whether preoperative blockade of nociceptive input with operative bupivacaine would exert a preemptive effect on postoperative analgesia. METHODS: 40 patients undergoing hysterectomy with general anesthesia were allocated randomly to receive either 0.25% bupivacaine 40ml infiltrated into the proposed wound line 10min before incision or no infiltration. Patient-controlled analgesia fentanyl and ketorolac were administered to both groups during first 48 postoperative hours. RESULTS: Pain scores and cumulative fentanyl and ketorolac consumption dosage at 12, 24, 36, 48 hours after surgery was similar in both groups. CONCLUSIONS: We concluded that preincisional infiltration with bupivacaine had no advantage in reducing postoperative analgesic requirements or pain scores after hysterectomy.