[Five Cases of Anesthetic Management for Femoral Neck Fracture Repair Complicated with Severe Aortic Stenosis].

Five elderly women complicated with severe aortic stenosis were admitted to our hospital due to femoral neck fracture. Maximum aortic jet velocity was above 5.0 m · s(-1) and aortic valve pressure gradient was above 100 mmHg. Every family wanted to have the fractured femoral neck repaired, despite a high mortality during periop- erative period. We anesthetized the patients with com- bined lumbar plexus and sciatic nerve block and mild sedation. The operation was performed uneventfully. Although one of them sometimes complained chest pain during postoperative period, all five patients could be discharged without catastrophic events. The definition of severe aortic stenosis is above 4.0 m · s(-1) of maximum aortic jet velocity and below 1.0 cm(2) of aortic valve orifice area. As the severity of aor- tic stenosis, increases anesthetic management becomes more difficult and risky. To block the sympathetic nervous system only in the injured leg, we performed combined lumbar plexus and sciatic nerve block at the injured side. Circulatory disturbance was considered to be less than spinal anesthesia. Although the patients suffered from traction pain at the healthy leg and peri- neal region, this method could be chosen in cases of femoral neck fracture repair complicated with severe aortic stenosis.

[A retrospective study on perioperative bleeding in patients for hip fracture surgery in patients treated with or without antiplatelet/anticoagulating drugs].

BACKGROUND: Early operation for hip fracture patients is considered to have better outcome. Therefore, early operation was performed even if patients had been treated with antiplatelet and/or anticoagulating drugs (AP/AC) in our hospital for the past two years. This retrospective study was undertaken as excessive blood loss is expected in patients treated with AP/AC. METHODS: Elderly patients for hip fracture surgery were retrospectively studied in our hospital for the past two years. Perioperative decrease in hemoglobin level and the incidence of transfusion were compared between patients treated with AP/AC and those not treated. RESULTS: Sixty-four patients were treated with AP/AC and one hundred ninety-nine patients were not treated. Patients treated with AP/AC had more preoperative complications and worse ASA-PS scores. General anesthesia was used more frequently for patients with AP/AC. In the perioperative decrease in hemoglobin level and the incidence of transfusion, there were no significant differences between the groups. CONCLUSIONS: Perioperative bleeding for hip fracture surgery was compared between patients treated with and without AP/AC. No significant difference was observed, and, discontinuation of AP/AC might not be necessary for hip fracture surgery.

[Asystole after anesthetic induction with remifentanil].

A 45-year-old man was scheduled for laparoscopic cholecystectomy. He had hypertension controlled with beta-adrenergic, calcium channel and angiotensin II receptor blocking agents. Because he had complications of symptomatic cervical spondylosis and sleep apnea syndrome, we performed awake fiberoptic intubation with remifentanil at a dose of 0.05 microg x kg(-1) min(-1). After intubation and following administration of propofol and vecuronium, ECG unexpectedly changed to asystole. We administered atropine 1.5 mg and performed chest compressions, which successfully restored sinus rhythm within 10 seconds. However, no cardiac disease was detected by a cardiologist. The operation was scheduled a week later again. Anti-hypertensive agents were discontinued. A temporary pacing wire was inserted before surgery, and atropine 0.5 mg was administered before anesthetic induction with remifentanil. No cardiac event was noticed through the perioperative period. We suggest that even a low dose of remifentanil may cause asystole in patients taking beta-adrenergic and calcium channel blocking agents, and preemptive administration of atropine may be effective.

[Anesthetic management of patients 100 years of age and above undergoing emergency abdominal surgery].

We anesthetized four patients aged 100 years and above who underwent emergency abdominal surgery. Case 1 : A 100-year-old woman with ileus caused by rectal cancer had chronic heart failure in whom colostomy was performed. Case 2 : A 101-year-old man with incarceration of inguinal hernia and history of cerebral infarction. Hernioplasty was performed. Case 3 : A 100-year-old woman with duodenal perforation and hypertension, in whom patching was performed. Case 4 : A 100-year-old bedridden man with incarceration of inguinal hernia who had enteral nutrition through gastrostoma, in whom hernioplasty was performed. General anesthesia was performed mainly with sevoflurane and all patients were discharged without any critical complications. Anesthetic management of elderly patients requires appropriate preoperative evaluation according to their complicating diseases, consciousness, activities of daily living and nutrition. Especially for patients aged 100 years and above, their quality of life should be evaluated. Surgical indication and procedure should be determined accordingly.

[Which anesthetic technique is more suitable for hip fracture surgery in patients above the age of 85, spinal or epidural?].

BACKGROUND: Anesthesia for hip fracture in elderly patients is a challenge because of their reduced functional reserve. We compared spinal and epidural anesthesia retrospectively in the operations of hip fracture in patients above the age of 85. METHODS: Two hundred and eighteen operations from April 1995 to September 2003 in our hospital were examined. Epidural anesthesia was scheduled in 94 operations, and bupivacaine spinal anesthesia in 86 operations. Successful anesthetic cases of each group were compared. Blood pressure, heart rate, doses of vasopressors used were recorded before anesthesia and first and second 30-minute periods after anesthesia. RESULTS: Failed anesthetic cases in epidural anesthesia were significantly more than those in spinal anesthesia. Blood pressure in the first 30-minute period after epidural anesthesia was significantly lower than that after spinal anesthesia. CONCLUSIONS: Spinal anesthesia is preferable for the operation for hip fracture compared with epidural anesthesia, because of fewer failed cases and smaller decreases of blood pressure.

[Combined paravertebral lumbar plexus and parasacral sciatic nerve block for reduction of hip fracture in four patients with severe heart failure].

We experienced four cases of anesthesia for hip fracture reduction in patients with severe heart failure, where anesthesia was attempted with combined paravertebral lumbar plexus and parasacral sciatic nerve block instead of spinal anesthesia. The anesthesia was successful without any sequelae. The patients' characteristics are as follows. Case 1: 97-year-old woman with severe heart failure and old myocardial infarction. Case 2: 91-year-old man with pacemaker, heart failure and heart valve disease. Case 3: 93-year-old woman with severe heart failure and multi-vessel coronary artery stenosis. Case 4: 83-year-old woman with congestive heart failure and heart valve disease. Paravertebral lumbar plexus block was performed with Touhy needle which was directed to lumbar transverse process, then re-directed caudally. Psoas compartment was felt with loss of resistance. Twelve ml of 0.25% bupivacaine was injected. Sciatic nerve block was performed with a needle which was inserted at the midpoint between the greater trochanter and the sacral hiatus without (case 1, 2) or with nerve stimulator (case 3, 4). Eight ml of 0.25% bupivacaine was injected. During the anesthesia, propofol was injected for light sedation. Although this combined nerve block is difficult to perform compared with spinal anesthesia, this could be applicable for hip fracture reduction anesthesia, especially in patients with severe heart failure.

Quantitative evaluation of the neuroprotective effects of hypothermia ranging from 34 degrees C to 31 degrees C on brain ischemia in gerbils and determination of the mechanism of neuroprotection.

OBJECTIVE: The present study was designed to determine whether the predominant factor responsible for neuroprotection of hypothermia ranging from 31 to 34 degrees C is prolongation of onset of ischemic depolarization or suppression of neuronal injury during ischemic depolarization and to quantitatively determine the neuroprotective effects of hypothermia of 34 degrees C and 31 degrees C. DESIGN: Prospective animal study. SETTING: A university research laboratory. SUBJECTS: Eighty-nine gerbils. INTERVENTIONS: Bilateral common carotid arteries were occluded for 3-20 mins. The brain temperature was set at 37 degrees C, 34 degrees C, or 31 degrees C before and during ischemic depolarization. MEASUREMENTS AND MAIN RESULTS: DC potentials were measured in the CA1 region, where histologic evaluation was performed 7 days later. Onset times of ischemic depolarization were 1.3 +/- 0.2, 1.6 +/- 0.4, and 2.4 +/- 0.7 mins at 37 degrees C, 34 degrees C, and 31 degrees C, respectively. The logistic regression curve demonstrated a close relationship between duration of ischemic depolarization and neuronal damage and showed a rightward shift by lowering the brain temperature. In the 37 degrees C, 34 degrees C, and 31 degrees C groups, the durations of ischemic depolarization causing 50% neuronal damage were estimated to be 8.0, 14.2, and 26.0 mins, respectively, and the ischemia times causing 50% neuronal damage were estimated to be 4.9, 8.1, and 14.2 mins, respectively. CONCLUSIONS: The onset of ischemic depolarization was prolonged in the 34 degrees C and 31 degrees C groups by only 0.3 and 1.1 mins, respectively, compared with that in the 37 degrees C group. Most of the neuroprotection by hypothermia was attributed to the suppression of neuronal injury during ischemic depolarization, suggesting that hypothermia has neuroprotective effects if it is initiated during the ischemic depolarization period. The results also indicate that the neuroprotective effect at 31 degrees C is about three times greater than that at 34 degrees C and that neuronal cells can withstand 2.9 times longer duration of ischemia at 31 degrees C than at 37 degrees C.

Dynamic changes in cortical NADH fluorescence and direct current potential in rat focal ischemia: relationship between propagation of recurrent depolarization and growth of the ischemic core.

Forty rats were subjected to 3 hours of focal ischemia by occluding the left middle cerebral and left common carotid arteries. The propagation of recurrent depolarization around the ischemic core was analyzed using direct-current potential and NADH (reduced nicotinamide adenine dinucleotide) fluorescence images by irradiating the parietal-temporal cortex with ultraviolet light. Based on histological evaluation at direct-current recording sites, the total time of depolarization causing 50% neuronal injury was estimated to be 18.2 minutes. The sites showing recurrent depolarizations resulted in 23 +/- 29% neuronal injury due to the short depolarization time, whereas the sites showing recurrent depolarizations and eventually persistent depolarization resulted in infarction. The NADH fluorescence images showed that recurrent depolarizations propagated along the margin of the ischemic core. In 85.9% of the recurrent depolarizations, the fluorescence disappeared without leaving any traces and did not affect the area of the ischemic core. However, in 47.5% of the animals, 14.1% of recurrent depolarizations merged with the ischemic core and increased the area by 6 +/- 4 mm(2). These findings suggest that recurrent depolarization increases the severity of neuronal injury but does not cause infarction by itself if persistent depolarization does not follow, and that the area of persistent depolarization is enlarged with 14.1% of recurrent depolarizations.