Intraoperative hemodynamics monitoring in a patient with pheochromocytoma multisystem crisis: a case report.

BACKGROUND: Pheochromocytoma is a rare catecholamine-secreting tumor. To evaluate the intraoperative hemodynamics with precision is difficult. CASE PRESENTATION: A 42-year-old man, who suddenly developed a life-threatening pheochromocytoma multisystem crisis that occurred during preoperative prophylactic medication, underwent urgent bilateral adrenalectomy. For the purpose of evaluating the intraoperative hemodynamics, we monitored both pulmonary artery catheter-based cardiac output (PACO) and arterial pressure-based cardiac output (APCO; FloTrac™). APCO fluctuated in poor agreement with the change in PACO, especially in the state of cytokine storming. CONCLUSIONS: Overall, the value of stroke volume variation derived from FloTrac™ changed in tandem with the intraoperative volume status, indicating its utility as a marker of circulatory hemodynamics.

Survey of blood pump diaphragm damage in the NIPRO-ventricular assist device.

We surveyed the incidence of blood pump diaphragm damage (rupture or crack) in the NIPRO-ventricular assist device (VAD). In the cases in which rupture or suspected blood pump crack was detected, we disassembled the pumps to visually check the condition of the diaphragm after replacement or use. Of 366 blood pumps surveyed, diaphragm damage was observed in 2.7 %. The duration of use of the blood pumps with diaphragm damage was significantly longer than that of pumps without damage. The incidence of diaphragm damage increased with longer duration of use. On the basis of these findings, blood pump diaphragm damage in the NIPRO-VAD may be associated with duration of use. However, some blood pumps were used for prolonged periods without diaphragm damage. All blood pumps with damage had a crack in the diaphragm on the air chamber side near the diaphragm-housing (D-H) junction. Cracks were not found in any specific part of the diaphragm. In blood pumps with diaphragm rupture, the crack had a through-hole reaching the blood-contacting surface. Although we were unable to identify the causes of the cracks, it is suggested that when a crack appears in the diaphragm it will gradually expand and eventually lead to rupture. If a crack is detected in a blood pump, we advocate replacing the pump before it grows. When the NIPRO-VAD is used, it is necessary to keep in mind that blood pump diaphragm damage may occur.

Left heart bypass support with the Rotaflow Centrifugal Pump® as a bridge to decision and recovery in an adult.

Since left heart bypass or biventricular circulatory assist with an extracorporeal centrifugal pump as a bridge to decision or recovery sometimes requires long-time support, the long-term durability of extracorporeal centrifugal pumps is crucial. The Rotaflow Centrifugal Pump(®) (MAQUET Cardiopulmonary AG, Hirrlingen, Germany) is one of the centrifugal pumps available for long-term use in Japan. However, there have been few reports of left heart bypass or biventricular circulatory support over the mid-term. This is a case report of left heart bypass support with the Rotaflow Centrifugal Pump(®) as a bridge to decision and recovery for an adult patient who could not be weaned from cardiopulmonary bypass and percutaneous cardiopulmonary support after cardiac surgery. We could confirm that the patient's consciousness level was normal; however, the patient could not be weaned from the left heart bypass support lasting 1 month. Therefore, the circulatory assist device was switched to the extracorporeal Nipro ventricular assist device (VAD). This time, left heart bypass support could be maintained for 30 days using a single Rotaflow Centrifugal Pump(®). There were no signs of hemolysis during left heart bypass support. The Rotaflow Centrifugal Pump(®) itself may be used as a device for a bridge to decision or recovery before using a VAD in cardiogenic shock patients.

Study of device malfunctions in patients with implantable ventricular assist devices living at home.

Clinical introduction of implantable ventricular assist devices (VADs) is expected to encourage VAD therapy for severe heart failure patients in Japan. Since even minor device malfunctions can lead to serious outcomes in these patients, it is very important to collect and analyze data on device malfunctions occurring during their use at home. This study was undertaken to collect and analyze such data from 9 patients with implanted VADs (EVAHEART™, 4 patients; Jarvik2000, 3 patients; Duraheart™, 2 patients) living at home, within the framework of a clinical trial carried out at our hospital. During the home stay period of 449 ± 253 days (range 12-801 days, total 4044 days), the total number of device malfunctions was 31 (0.31 events/patient/year). Those with EVAHEART™ were Cool-seal system-related (9 events) and battery-related (6 events) malfunctions. Those with Jarvik2000 were battery-related (7 events), alarm (1 event) and uncertain cause (1 event) malfunctions. Those with Duraheart™ were battery-related (3 events), alarm (3 events) and other component (1 event) malfunctions. Although the incidence was not very high and none of these device malfunctions led to cessation of blood pump operation in this study, it is necessary to establish a communication system for properly obtaining detailed information in the event of serious device malfunctions. Furthermore, establishment of a home-living-patient support system covering extensive areas is urgently needed, since this can facilitate rapid action to deal with serious device malfunctions.

Role for cyclooxygenase 2 in the development and maintenance of neuropathic pain and spinal glial activation.

BACKGROUND: Lines of evidence have indicated that cyclooxygenase 2 plays a role in the pathophysiology of neuropathic pain. However, the site and mechanism of its action are still unclear. Spinal glia has also been reported to mediate pathologic pain states. The authors evaluated the effect of continuous intrathecal or systemic cyclooxygenase-2 inhibitor on the development and maintenance of neuropathic pain and glial activation in a spinal nerve ligation model of rats. METHODS: Continuous intrathecal infusion of meloxicam (32 or 320 mug . kg . day) or saline was started immediately after L5-L6 spinal nerve ligation. Mechanical allodynia and thermal hyperalgesia were evaluated on days 4 and 7 postoperatively. Spinal astrocytic activation was evaluated with glial fibrially acidic protein immunoreactivity on day 7. In other groups of rats, continuous intrathecal meloxicam was started 7 days after spinal nerve ligation, and effects on established neuropathic pain and glial activation were evaluated. Last, effects of continuous systemic meloxicam (16 mg . kg . day) on existing neuropathic pain and glial activation were examined. RESULTS: Intrathecal meloxicam prevented the development of mechanical allodynia and thermal hyperalgesia induced by spinal nerve ligation. It also inhibited spinal glial activation responses. In contrast, when started 7 days after the nerve ligation, intrathecal meloxicam did not reverse established neuropathic pain and glial activation. Systemic meloxicam started 7 days after ligation partially reversed neuropathic behaviors but not glial activation. CONCLUSIONS: Spinal cyclooxygenase 2 mediates the development but not the maintenance of neuropathic pain and glial activation in rats. Peripheral cyclooxygenase 2 plays a part in the maintenance of neuropathic pain.

The electrical properties of epidural catheters: what are the requirements for nerve stimulation guidance?

We designed the present study to investigate the electrical resistance of commercially available epidural catheters and to search for products and procedures suitable for nerve stimulation-guided insertion. Four types of epidural catheters were evaluated: 2 nonwire-reinforced catheters (19-gauge and 20-gauge nylon) and 2 wire-reinforced catheters (19-gauge without stylet and 20-gauge with stylet). The resistance of a catheter was calculated from the voltage level proportional to the fixed resistance in series circuit. In case of physiologic saline, the resistance of nonreinforced catheters was more than 700 kOmega, whereas the wire-reinforced catheter was 14.4 +/- 0.20 kOmega without stylet and 10.1 +/- 0.42 kOmega with stylet. When the stylet was passed through a 20-gauge nylon catheter, the resistance decreased to 49.2 +/- 1.96 kOmega. When catheters were primed with 10% hypertonic saline, the resistance of both nonreinforced catheters decreased by one third compared with physiologic saline. The electrical resistance of the saline-filled epidural catheters significantly differed among products tested. We conclude that epidural catheterization that is guided by electrical stimulation should be performed only with catheters equipped with spiral stainless steel wire reinforcement or with a stainless steel stylet.

Anti-allodynic and anti-hyperalgesic effects of nociceptin receptor antagonist, JTC-801, in rats after spinal nerve injury and inflammation.

The effects of nociceptin/orphanin FQ (N/OFQ) peptide receptor antagonist JTC-801 on allodynia and hyperalgesia were examined in rats in order to explore the involvement of N/OFQ system in these pathological pain states. Tactile allodynia induced by L5/L6 spinal nerve ligation was reversed by both systemic (3-30 mg/kg) and spinal (22.5 and 45 pg) JTC-801 in a dose-dependent manner. Concerning hyperalgesia induced by formalin injection into the hindpaw, JTC-801 dose-dependently suppressed the second phase, but not the first phase, of the licking behavior. Furthermore, systemic JTC-801 reduced Fos-like immunoreactivity in the dorsal horn of the spinal cord (laminae I/II). In conclusion, N/OFQ receptor antagonist JTC-801 exerted anti-allodynic and anti-hyperalgesic effects in rats, suggesting that N/OFQ system might be involved in the modulation of neuropathic pain and inflammatory hyperalgesia.

Change in bispectral index during epileptiform electrical activity under sevoflurane anesthesia in a patient with epilepsy.

UNLABELLED: We observed abnormal fluctuation in Bispectral Index (BIS) caused by repeated alternations between two electroencephalographic (EEG) waveform patterns in a patient with a recent history of epileptic seizure under sevoflurane anesthesia. The repetitive development of the abnormal EEG changes (slow delta with or without spike) and the fluctuation in BIS disappeared almost immediately after administration of anticonvulsants. BIS may give useful information not only on the sedative-hypnotic state, but also on the development of and recovery from abnormal epileptiform EEG activity. IMPLICATIONS: During epileptiform electroencephalographic activity (EEG), the Bispectral Index shows an abnormal fluctuation caused by repeated abrupt alterations between normal EEG and abnormal epileptiform EEG patterns.

Effect of methylprednisolone on neuropathic pain and spinal glial activation in rats.

BACKGROUND: Basic data are lacking regarding the efficacy and mechanisms of action of corticosteroids in neuropathic pain. Because recent studies indicate that spinal glial activation mediates the pathologic pain states, the authors sought to determine the effects of systemic and intrathecal methylprednisolone on the development and maintenance of neuropathic pain and spinal glial activation in a rat model. METHODS: Rats were anesthetized, and L5 and L6 spinal nerves were tightly ligated. Then, continuous infusion of systemic (4 mg x kg(-1) x day(-1)) or intrathecal (80 microg x kg(-1) x day(-1)) methylprednisolone or saline was started. Mechanical allodynia and thermal hyperalgesia were evaluated on days 4 and 7 postoperatively with von Frey and Hargreaves tests, respectively. Spinal astrocytic activation was evaluated with glial fibrillary acidic protein immunoreactivity on day 7. In other groups of rats, continuous 3-day treatment with intrathecal methylprednisolone or saline was started 7 days after spinal nerve ligation, when neuropathic pain had already developed. Behavioral tests and immunostaining were performed up to 3 weeks after the treatment. RESULTS: Spinal nerve ligation induced mechanical allodynia and thermal hyperalgesia on days 4 and 7 postoperatively. Glial fibrillary acidic protein immunoreactivity was remarkably enhanced on day 7. Both systemic and intrathecal methylprednisolone inhibited the development of neuropathic pain states and glial activation. Three-day treatment with intrathecal methylprednisolone reversed existing neuropathic pain state and glial activation up to 3 weeks after the treatment. CONCLUSION: : Systemic and intrathecal methylprednisolone inhibited spinal glial activation and the development and maintenance of a neuropathic pain state in a rat model of spinal nerve ligation.

Thoracic epidural catheter insertion using the caudal approach assisted with an electrical nerve stimulator in young children.

OBJECTIVES: We evaluated whether thoracic epidural catheter placement using the caudal approach and assisted with an electrical stimulator could be performed in young children. METHODS: Ten young children (1-4 years) who underwent abdominal surgeries were studied. Under general anesthesia without muscle relaxants, caudal catheter placement was performed using an 18-gauge Crawford-type needle and a 20-gauge radiopaque epidural catheter with a stainless-steel stylet. A metal adapter and a 3-way stopcock were attached to the catheter to connect to an electrical stimulator and to inject physiological saline. Electrical stimulation was performed intermittently while advancing the catheter until it reached the target length. The catheter position was confirmed on postoperative roentgenogram. RESULTS: The mean age of the subjects was 32.2 +/- 10.1 months (13-48 months), and the height was 85.3 +/- 6.1 cm (72-93 cm). In 9 of 10 patients, an epidural catheter could be placed at the first insertion. In 1 patient, the catheter could be placed successfully at the second insertion. The electrical current required for muscle contraction at the target length was 5.8 +/- 1.5 mA. CONCLUSION: Electrical stimulation reliably indicated the location of the catheter tip. This technique for thoracic epidural catheter insertion was easy to perform and could be used in young children.

[A case of latex anaphylactoid reaction starting with respiratory symptoms].

We report a case of latex anaphylactoid reaction in a 39-year-old man with aortitis. He was scheduled to undergo stent-graft implantation. When the operation progressed into his abdomen, respiratory symptoms, wheezing and high airway pressure, occurred. However, he did not show any dermal symptoms. Thirty-five minutes after the start of respiratory symptoms, his face suddenly showed flush, and intravenous epinephrine worked successfully against anaphylactoid reactions. There are anaphylactoid reactions which occurred with respiratory symptoms, and we should be aware of these cases.

[The effect of intrathecal fentanyl added to hyperbaric bupivacaine for caesarean section].

BACKGROUND: Management of cesarean section with spinal anesthesia is often accompanied with intraoperative nausea and pain. In a randomized controlled study, we explored the effect of intrathecal fentanyl on the characteristics of subarachnoid block in patients undergoing cesarean section. METHODS: Twenty-four healthy parturients scheduled for elective Cesarean section were allocated to receive either fentanyl 0.3 ml (15 micrograms) or 0.9% saline 0.3 ml added to 0.5% hyperbaric bupivacaine 2.0 ml given intrathecally in the right decubitus position (n = 12 in each group). Level of sensory blockade was evaluated with cold test and intraoperative use of antiemetics and analgesics was recorded. RESULTS: The maximum level of sensory blockade was significantly higher in the fentanyl group as compared with the control group (P = 0.019). Use of intraoperative antiemetics was significantly less often in the fentanyl group (P = 0.007). The required amount of intraoperative analgesics was smaller in the fentanyl group, although the difference was not significant (P = 0.11). No remarkable side effects, such as respiratory depression and hypoxia were observed. Apgar scores in the newborn were similar. CONCLUSION: Addition of intrathecal fentanyl to hyperbaric bupivacaine in parturients undergoing cesarean section improved quality of anesthesia without producing significant side effects.

Serum and cerebrospinal fluid concentrations of midazolam after epidural administration in dogs.

UNLABELLED: The epidural administration of midazolam has analgesic effects that might be mediated by gamma-aminobutyric acid type A receptors in the spinal cord. In this study, we examined both serum and cerebrospinal fluid (CSF) concentrations of midazolam after epidural administration to investigate the possibility of midazolam entering CSF directly from the epidural space. Five male mongrel dogs had catheters inserted in a femoral artery, the epidural space at L3-4, and the intrathecal space at the atlanto-occipital region under general anesthesia. Midazolam 1 mg/kg was epidurally administered, and arterial blood and CSF samples were collected until 240 min after the midazolam administration to measure midazolam concentration. Serum midazolam concentration increased and reached a peak at 30 min after the administration (224.8 +/- 30.5 ng/mL) and then decreased to 25.8 +/- 6.0 ng/mL at 240 min. Midazolam concentration in the CSF was less than the detection limit at 5 min, reached a peak at 30 min after the administration (7.2 +/- 4.7 ng/mL), and decreased to 3.6 +/- 3.3 ng/mL at 240 min. In conclusion, epidurally administered midazolam enters CSF, but CSF concentrations are only 3% of those in the systemic circulation. IMPLICATIONS: Midazolam, which has spinally mediated analgesic potency, was epidurally administered in dogs, and serum and cerebrospinal fluid concentrations were measured. Epidurally administered midazolam enters the cerebrospinal fluid, but concentrations are only 3% of those in the systemic circulation.

[Perioperative management for carotid endoarterectomy with induced mild hypothermia: a case report].

We report perioperative management for carotid endoarterectomy with induced mild hypothermia in a patient with severe stenosis of the bilateral carotid arteries. The patient was a 47 year-old male with familial hyperlipidemia and history of coronary artery bypass surgery. Angiography revealed severe stenotic lesions of the right internal carotid artery (ICA) and total occlusion of the left ICA. Endoarterectomy for the right ICA was planned. Anesthesia was induced and maintained with fentanyl, midazolam, pancuronium and sevoflurane. Electroencephalogram and near-infrared cerebral oxymetry were employed for monitoring intraoperatively. Temporary shunting was used during clamping of the right carotid artery because collateral blood flow could not be expected due to total occlusion of the left ICA. Furthermore, mild hypothermia down to 34 degree C was induced for brain protection with the use of a cooling blanket. After the surgery, the patient was transferred to ICU under deep anesthesia and controlled ventilation. Anesthesia was lightened gradually after rewarming to prevent postoperative shivering. The patient left ICU on the second postoperative day without any neurological deficits.

[Usefulness of multi-lead electrocardiogram and transesophageal echocardiography for the detection and evaluation of intraoperative coronary spasm].

We describe a case of coronary spasm in a 59-year-old man undergoing an emergent abdominal aortic replacement for ruptured aortic aneurysm. The patient was brought to the operating room in a state of hypovolemic shock, and was successfully resuscitated through intensive volume expansion by rapid infusion devices. Twenty minutes after cross-clamping of the abdominal aorta, ST-segment elevation on the lead III of electrocardiogram (ECG) and dyskinesis in the inferior wall shown by transesophageal echocardiography (TEE) were noted. Coronary spasm was suspected, and isosorbide dinitrate was administered intravenously without delay, leading to prompt reversal of ischemic changes. A number of reports have suggested that care should be taken against coronary spasm in non-cardiac surgery as well as cardiac surgery, especially in patients with coronary risk factors. Monitoring by multi-lead ECG and TEE is a powerful method by which to detect and evaluate intraoperative myocardial ischemia.