Effect of nephrostomy sheath size on renal pelvic pressure during endoscopic combined intrarenal surgery: artificial kidney model study.

BACKGROUND: This study aimed to evaluate the intrarenal pelvic pressure in endoscopic combined intrarenal surgery using an artificial kidney model. METHODS: An artificial kidney model was created using the Urovac evacuator™. Four sizes of nephrostomy sheaths (MIP-L: 25/26 Fr, MIP-M: 16.5/17.5 Fr, MIP-S: 11/12 Fr, MIP-XS: 8.5/9.5 Fr) and two sizes of ureteral access sheaths (12/14 Fr and 10/12 Fr) were installed into the model. For each combination of nephrostomy and ureteral access sheath, renal pelvic pressure was measured with and without insertion of the retrograde flexible ureteroscope. Irrigation from the nephroscope was adjusted to 40-160 mmHg using an automatic irrigation device, and the irrigation of the ureteroscope was by spontaneous dripping at 80 cmH2O. Conditions were measured six times, and the renal pelvic pressure was compared in different conditions. RESULTS: Without ureteroscope insertion through the ureteral access sheath, the renal pelvic pressure never exceeded 30 mmHg. Meanwhile, when the ureteroscope was inserted, the renal pelvic pressure increased as the nephrostomy sheath and ureteral access sheath became narrower and as the irrigation pressure increased. Intrarenal pelvic pressure exceeded 30 mmHg when the irrigation pressure was increased in 12/14 Fr ureteral access sheath when MIP-XS was used, and in 10/12 Fr ureteral access sheath when MIP-XS and MIP-S were used. CONCLUSIONS: The use of a thin nephrostomy sheath in endoscopic combined intrarenal surgery can lead to increased intrarenal pelvic pressure. Although our results are from an artificial kidney model, special care is suggested to be required when using a retrograde flexible ureteroscope simultaneously in treatment of patients.

Efficacy of metyrapone for symptoms of adrenocortical carcinoma.

Elevated cortisol by adrenocortical carcinoma leads to a variety of symptoms. We report on the efficacy of metyrapone in treatment of a variety of distressing symptoms caused by elevated cortisol in a patient who refused advanced treatment for adrenocortical carcinoma.

In vitro comparison of simulated intrapelvic pressure in an artificial kidney model during retrograde intrarenal surgery among various single-use ureteroscopes.

OBJECTIVES: This study compares intrapelvic pressure (IPP) during retrograde intrarenal surgery with various single-use flexible ureteroscopes (f-URS) in an artificial kidney model. METHODS: We created an artificial kidney model with a pressure sensor using a bladder evacuation device. The model was completely closed and the only backflow was on the side of the ureteroscope inside the ureteral access sheath (UAS). We tested five single-use f-URSs (LithoVue, Wiscope, PU3022A, PU3033A, and AXIS) with six different types of UAS (9.5/11.5-14/16 Fr). Using the automatic irrigation system, 30 s of irrigation was performed at various pressures (40-180 mmHg) and steady-state IPP was recorded. IPP was compared between the five single-use f-URSs. IPP cutoff value was determined at 30 mmHg. The diameter of the endoscope tip and the curved and shaft parts were also measured and recorded. RESULTS: The diameters of all parts were significantly different between single-use f-URSs. The maximum IPP tended to be higher in ureteroscopes with larger diameters of the proximal parts (curved part/shaft part). In LithoVue and Uscope PU3022A f-URSs, the maximum IPP did not exceed 30 mmHg when UAS ≥12/14 Fr was used. In AXIS and Wiscope f-URSs, it did not exceed the cutoff value when the UAS ≥11/13 Fr was used. In Uscope PU3033A f-URS, it did not exceed 30 mmHg when the UAS ≥10/12 Fr was used. CONCLUSIONS: Maximum IPP tended to be higher in f-URSs with larger diameters of the proximal part and the appropriate size of the UAS differed between various single-use f-URSs.

Activation of Transient Receptor Potential Vanilloid 1 Is Involved in Both Pain and Tumor Growth in a Mouse Model of Cancer Pain.

Activation of calcitonin gene-related peptide (CGRP)-positive sensory neurons in the tumor microenvironment has been shown to be involved in tumor growth. However, how CGRP-positive sensory neurons are activated requires elucidation. In this study, we focused on transient receptor potential vanilloid 1 (TRPV1) and examined the contribution of TRPV1 to tumor growth and cancer pain in a mouse cancer model in which Lewis lung carcinoma was subcutaneously inoculated in the left plantar region. Tumor inoculation gradually increased the volumes of the hind paws of wild type (WT) mice over time, but those of both αCGRP knockout mice and TRPV1 knockout mice were significantly smaller than those of WT mice after tumor inoculation. Both TRPV1 and CGRP are therefore suggested to be involved in tumor growth. In an immunohistochemical study, the percentage of phosphorylated cyclic adenosine monophosphate response element-binding protein (p-CREB)-positive profiles in CGRP-positive dorsal root ganglion (DRG) neurons in WT mice was significantly increased after tumor inoculation. The percentage of p-CREB-positive profiles in CGRP-positive DRG neurons in TRPV1 knockout mice was also increased after tumor inoculation, but was significantly lower than that in WT mice, indicating the contribution of TRPV1 to activation of CGRP-positive DRG neurons. Cancer pain in TRPV1 knockout mice was significantly lower than that in WT mice. In conclusion, TRPV1 is involved in both tumor growth and cancer pain, potentially leading to a novel strategy for the treatment of cancer pain and cancer development. Cancer pain is also suggested to facilitate tumor growth.

Tmem45b is essential for inflammation- and tissue injury-induced mechanical pain hypersensitivity.

Persistent mechanical pain hypersensitivity associated with peripheral inflammation, surgery, trauma, and nerve injury impairs patients' quality of life and daily activity. However, the molecular mechanism and treatment are not yet fully understood. Herein, we show that chemical ablation of isolectin B4-binding (IB4+) afferents by IB4-saporin injection into sciatic nerves completely and selectively inhibited inflammation- and tissue injury-induced mechanical pain hypersensitivity while thermal and mechanical pain hypersensitivities were normal following nerve injury. To determine the molecular mechanism involving the specific types of mechanical pain hypersensitivity, we compared gene expression profiles between IB4+ neuron-ablated and control dorsal root ganglion (DRG) neurons. We identified Tmem45b as one of 12 candidate genes that were specific to somatosensory ganglia and down-regulated by IB4+ neuronal ablation. Indeed, Tmem45b was expressed predominantly in IB4+ DRG neurons, where it was selectively localized in the trans Golgi apparatus of DRG neurons but not detectable in the peripheral and central branches of DRG axons. Tmem45b expression was barely detected in the spinal cord and brain. Although Tmem45b-knockout mice showed normal responses to noxious heat and noxious mechanical stimuli under normal conditions, mechanical pain hypersensitivity was selectively impaired after inflammation and tissue incision, reproducing the pain phenotype of IB4+ sensory neuron-ablated mice. Furthermore, acute knockdown by intrathecal injection of Tmem45b small interfering RNA, either before or after inflammation induction, successfully reduced mechanical pain hypersensitivity. Thus, our study demonstrates that Tmem45b is essential for inflammation- and tissue injury-induced mechanical pain hypersensitivity and highlights Tmem45b as a therapeutic target for future treatment.

A Case of Decreased Amplitude in Motor Evoked Potentials Under Remimazolam Anesthesia.

Remimazolam is a newly developed benzodiazepine derivative. Although one case report on the use of remimazolam for motor evoked potential (MEP) monitoring has been reported, there has been no report of changes in the MEP response under remimazolam anesthesia, which is associated with impairment of the corticospinal motor track. This is a case of a 54-year-old woman who was diagnosed with an extradural extramedullary tumor. The patient reported being allergic to chicken eggs. We used remimazolam instead of propofol for anesthesia management. During tumor resection, the amplitudes of MEP responses at the left quadriceps femoris, left tibialis anterior, and left abductor hallucis muscle decreased. The surgery was scaled down and the tumor was removed in a reduced size. The patient had muscle weakness immediately after surgery but eventually recovered. In this case, we could detect changes in MEP response under remimazolam anesthesia, which suggested impairment of the motor tracts during surgery.

Prevention of trigeminocardiac reflex-induced severe bradycardia during cerebral aneurysm clipping surgery by topical anesthesia of the dura surface and atropine administration: a case report.

BACKGROUND: Trigeminocardiac reflex (TCR) by stimulation of the sensory branch of the trigeminal nerve induces transient bradycardia and hypotension. We report a case in which light mechanical stimulation to the dura mater during brain surgery induced severe bradycardia. CASE PRESENTATION: A 77-year-old woman with bradycardia-tachycardia syndrome was scheduled for clipping of an unruptured left middle cerebral artery aneurysm. General anesthesia was performed with propofol, remifentanil, and rocuronium. Before starting surgery, the function of the pyramidal tract was examined by motor evoked potential. Transcranial electric stimulation for motor evoked potential induced atrial fibrillation and tachycardia. Continuous administration of landiolol was started and verapamil was used for tachycardia. During detachment of the dura mater from the bone, an electrocardiogram suddenly showed sinus arrest for 6 s. Immediately after the manipulation was interrupted, a junctional rhythm appeared. However, light touch to the dura mater induced severe bradycardia again, and atropine was therefore administered. In addition, the dura surface was anesthetized with topical lidocaine infiltration. After that, light touch-induced bradycardia was prevented. CONCLUSIONS: We experienced a case of severe bradycardia during surgery due to TCR caused by light mechanical stimulation to the dura mater. Topical anesthesia of the dura surface and atropine administration were effective for preventing TCR-induced bradycardia.

Comparison of plasma concentrations of levobupivacaine with and without epinephrine for thoracic paravertebral block: A randomised trial.

BACKGROUND: Thoracic paravertebral block (TPVB) is effective for analgesia for unilateral thoracic surgery. However, since the paravertebral space is highly vascular, injection of local anaesthetics into the paravertebral space may induce systemic local anaesthetic toxicity. We examined the effect of addition of epinephrine to paravertebral levobupivacaine on its plasma concentration. METHODS: In a randomised single blind trial, twenty-four male patients who were scheduled to undergo elective unilateral pulmonary lobectomy or segmentectomy under general anaesthesia combined with TPVB were enrolled in this study. They were randomly divided into two groups: one group received a single bolus thoracic paravertebral injection of 1 mg/kg of 0.25% levobupivacaine with 5 µg/mL epinephrine and the other group received a single bolus thoracic paravertebral injection of 1 mg/kg of 0.25% levobupivacaine alone. Arterial blood samples were obtained for plasma levobupivacaine assay after injection. The peak plasma concentration (Cmax) and the time to peak plasma concentration (Tmax), for levobupivacaine were calculated. RESULTS: There were no significant differences in patients' characteristics between the two groups. The mean arterial Cmax values of levobupivacaine were 0.48 ± 0.11 µg/mL with epinephrine and 0.71 ± 0.31 µg/mL without epinephrine (P = 0.041). The mean arterial Tmax values of levobupivacaine were 46.0 ± 35.6 min with epinephrine and 12.0 ± 7.2 min without epinephrine (P = 0.005). CONCLUSION: The addition of 5-µg/mL epinephrine to a single bolus thoracic paravertebral injection of 1-mg/kg levobupivacaine significantly decreased Cmax and delayed Tmax of levobupivacaine. The addition of epinephrine to levobupivacaine may be a useful strategy to reduce systemic levobupivacaine toxicity. CLINICAL TRIAL REGISTRATION NUMBER: UMIN 000021942.

Factors associated with quality of dreams during general anesthesia: a prospective observational study.

Patients frequently report having dreams during general anesthesia, and the dreams are often reported to be pleasant dreams. However, factors associated with the quality of dreams during general anesthesia have not been clarified. The aim of this study was to determine the relationships between the quality of dreams during general anesthesia and perioperative factors. This prospective observational study included patients scheduled for elective surgery under general anesthesia. Preoperative mental status was assessed by the Hospital Anxiety and Depression Scale (HADS). A postoperative interview was carried out in the operating room after recovery from general anesthesia. Dreams and awareness during general anesthesia were assessed by a modified Brice interview. The quality of dreams was classified in accordance with the patient's own opinion as pleasant, indifferent, or unpleasant. A total of 1100 patients were included in the study, and 293 (25.4%) of the patients reported having dreams during anesthesia. Half of the patients who experienced dreams during anesthesia (50.2%, 147/293 patients) reported having a pleasant dream. Multivariate logistic regression analysis revealed that only HADS-depression score of less than 11 was related to pleasant dreams (OR: 3.3 [95% CI 1.3-10.0]).

Validation of noninvasive continuous arterial pressure measurement by ClearSight System™ during induction of anesthesia for cardiovascular surgery.

BACKGROUND: Since blood pressure tends to be unstable during induction of anesthesia in patients undergoing cardiovascular surgery, an artery catheter is often inserted before induction to continuously monitor arterial pressure during induction of anesthesia. ClearSight System™ enables noninvasive continuous measurement of beat-to-beat arterial pressure via a single finger cuff without pain using photoplethysmographic technology. If ClearSight System™ can replace intra-arterial pressure measurement, blood pressure could be easily and noninvasively assessed. However, the validity of ClearSight System™ during induction of anesthesia in patients undergoing cardiovascular surgery has not been evaluated. The aim of this study was to compare blood pressure measured by ClearSight System™ with intra-arterial pressure during induction of anesthesia for cardiovascular surgery. METHODS: This study was registered retrospectively. Data during induction of anesthesia for elective cardiovascular surgery were obtained for patients in whom noninvasive arterial pressure was measured by ClearSight System™ (APcs) and invasive radial arterial pressure (APrad) was measured simultaneously. According to the widely used criteria formulated by international standards from the Association for the Advancement of Medical Instrumentation, the acceptable bias and precision for arterial pressure measurements were fixed at < 5 mmHg and 8 mmHg, respectively. RESULTS: Data for 18 patients were analyzed. For 3068 analyzed paired measurements, values of APcs vs APrad bias (precision) were 13.2 (17.5), - 9.1 (7.3) and - 3.9 (7.8) mmHg for systolic, diastolic, and mean arterial pressures, respectively. CONCLUSIONS: Mean arterial pressure measured by ClearSight System™ could be considered as an alternative for mean radial arterial pressure during induction of anesthesia for elective cardiovascular surgery.

Optimal Timing of Removal of Epidural and Urethral Catheters to Avoid Postoperative Urinary Retention Undergoing Abdominal Surgery.

BACKGROUND/AIMS: Postoperative urinary retention (POUR) is one of the most frequent complications of epidural anesthesia. This study aims to clarify risk factors of POUR and to estimate the appropriate timing of urethral catheter removal. METHODS: Between September and December 2014, a retrospective cohort study was conducted on 120 patients who underwent epidural anesthesia and major abdominal surgery. To observe trends in incidence of POUR, we analyzed the order and interval of removal of epidural and urethral catheters using Cochran-Armitage trend test. RESULTS: In this study, 40 patients were diagnosed with POUR (33.3%). Median removal of epidural catheters was 4 postoperative days in the POUR group and 3.5 postoperative days in the non-POUR group (p = 0.04). When the urethral catheter was removed before epidural catheter, incidence of POUR was comparatively greater (p < 0.001). There were no statistical differences in surgical fields, operation approach, epidural catheter levels, or epidural opioid use. No patients had urinary tract infections. CONCLUSION: We demonstrated that removal of urethral catheter before epidural catheter contributed to increasing trends in incidence of POUR. The optimal order and interval of removal of epidural and urethral catheters should be considered to avoid POUR after abdominal surgery.

Comparison of catheter-over-needle and catheter-through-needle on leakage from the catheter insertion site during continuous femoral nerve block.

The aim of this study was to compare the incidences of leakage from the catheter insertion site during continuous femoral nerve block when using the catheter-through-needle, Contiplex Touhy™ (CT) and the newly developed catheter-over-needle, Contiplex C™ (CC). Forty adult patients who were scheduled to undergo continuous femoral nerve block for pain control following knee surgery were enrolled and were randomly assigned to a CT group or a CC group. After finishing surgery, a catheter for continuous femoral nerve block was placed using ultrasound. A catheter was advanced along the femoral nerve 5-6 cm beyond the needle tip. Then 0.25% levobupivacaine was continuously administered at a rate of 5 ml/h until 9:00 am on postoperative day 1. The incidence of leakage of the local anesthetic from the insertion site in the CT group was significantly higher than that in the CC group. In the CT group, leakage from the catheter insertion site was observed in 11 of 20 patients during the observation period. On the other hand, none of the patients in the CC group showed leakage. Contiplex C™ is more effective than Contiplex Touphy™ for prevention of leakage of local anesthetics from the insertion site during continuous femoral nerve block.

Systemic QX-314 Reduces Bone Cancer Pain through Selective Inhibition of Transient Receptor Potential Vanilloid Subfamily 1-expressing Primary Afferents in Mice.

BACKGROUND: The aim of this study was to determine whether systemic administration of QX-314 reduces bone cancer pain through selective inhibition of transient receptor potential vanilloid subfamily 1 (TRPV1)-expressing afferents. METHODS: A mouse model of bone cancer pain was used. The authors examined the effects of bolus (0.01 to 3 mg/kg, n = 6 to 10) and continuous (5 mg kg h, n = 5) administration of QX-314 on both bone cancer pain-related behaviors and phosphorylated cyclic adenosine monophosphate response element-binding protein expression in dorsal root ganglion neurons (n = 3 or 6) and the effects of ablation of TRPV1-expressing afferents on bone cancer pain-related behaviors (n = 10). RESULTS: The numbers of flinches indicative of ongoing pain in QX-314-treated mice were smaller than those in vehicle-treated mice at 10 min (3 mg/kg, 4 ± 3; 1 mg/kg, 5 ± 3 vs. 12 ± 3; P < 0.001; n = 8 to 9), 24 h (3 ± 2 vs. 13 ± 3, P < 0.001), and 48 h (4 ± 1 vs. 12 ± 2, P < 0.001; n = 5 in each group) after QX-314 administration, but impaired limb use, weight-bearing including that examined by the CatWalk system, and rotarod performance indicative of movement-evoked pain were comparable. QX-314 selectively inhibited the increase in phosphorylated cyclic adenosine monophosphate response element-binding protein expression in TRPV1-positive, but not in TRPV1-negative, dorsal root ganglion neurons compared to that in the case of vehicle administration (32.2 ± 3.0% vs. 52.6 ± 5.9%, P < 0.001; n = 6 in each group). Ablation of TRPV1-expressing afferents mimicked the effects of QX-314. CONCLUSION: This study showed that systemic administration of QX-314 in mice inhibits some behavioral aspects of bone cancer pain through selective inhibition of TRPV1-expressing afferents without coadministration of TRPV1 agonists.

Anesthetic management of a patient with factor VII deficiency undergoing laparoscopic colectomy: a case report.

BACKGROUND: Congenital factor VII (FVII) deficiency is a rare autosomal recessive coagulation disorder that is characterized by prolongation of prothrombin time. Recombinant activated FVII (rFVIIa) is widely used in the management of bleeding in patients with congenital FVII deficiency. We experienced anesthetic management of a patient with congenital FVII deficiency who was scheduled for laparoscopic colectomy using rFVIIa. CASE PRESENTATION: We report a 67-year-old man with rectal cancer who was diagnosed with congenital FVII deficiency. He was scheduled for laparoscopic colectomy. General anesthesia was performed with propofol, remifentanil, and rocuronium without epidural anesthesia. For coagulation management, 1 mg of rFVIIa was intravenously administered before starting surgery. During surgery, FVII activity and prothrombin time-international normalized ratio (PT-INR) were maintained to be above 10 % and within the normal range (0.8-1.2), respectively. The surgery was uneventfully completed. CONCLUSIONS: We reported successful management of a patient with congenital FVII deficiency undergoing laparoscopic colectomy with monitoring of FVII activity and/or PT-INR.

Inhibitory effect of bisphosphonate on osteoclast function contributes to improved skeletal pain in ovariectomized mice.

The aim of this study was to evaluate skeletal pain associated with osteoporosis and to examine the inhibitory effect of bisphosphonate (BP) on pain in an ovariectomized (OVX) mouse model. We evaluated skeletal pain in OVX mice through an examination of pain-like behavior as well as immunohistochemical findings. In addition, we assessed the effects of alendronate (ALN), a potent osteoclast inhibitor, on those parameters. The OVX mice showed a decrease in the pain threshold value, and an increase in the number of c-Fos immunoreactive neurons in laminae I-II of the dorsal horn of the spinal cord. Alendronate caused an increase in the pain threshold value and inhibited c-Fos expression. The serum level of tartrate-resistant acid phosphatase 5b, a marker of osteoclast activity, was significantly negatively correlated with the pain threshold value. Furthermore, we found that an antagonist of the transient receptor potential channel vanilloid subfamily member 1, which is an acid-sensing nociceptor, improved pain-like behavior in OVX mice. These results indicated that the inhibitory effect of BP on osteoclast function might contribute to an improvement in skeletal pain in osteoporosis patients.

[Anesthetic management for abdominoperineal resection of the rectum in a patient with superior vena cava syndrome].

Since superior vena cava syndrome (SVCs) causes ntracranial hypertension and edema of the upper respiratory tract close attention should be paid to brain circulatory dysfunction and obstruction of the upper airway. A male patient with SVCs and complete obstruction of the bilateral internal jugular veins was scheduled for abdominoperineal resection of the rectum under general anesthesia To evaluate the brain circuation, we monitored the external jugular venous pressure and regional saturation of oxygen (rSO) by INVOS® in the cerebral frontal cortex. If the external ugular venous pressure would rise above 20 mmHg, we planned to change the horizontal supine position to a head up position and then remove blood from the external jugular vein. Fortunately, since the external jugular venous pressure was maintained within 20 mmHg, and since no great decreases in rSO2 occurred during surgery, we did not change the patient's position or remove blood from the patient. The surgical procedure was completed uneventfully, and pharyngoarngeal edema was not seen. He did not show any neurological deficits after surgery. From experience of khis patient, we concluded that monitoring of external cigular venous pressure and rSO2 is useful for anesthetic management in patints with SVCs.

[Case of parturient who underwent resection of a spinal Tumor].

Spinal tumors are rare in pregnancy, but they cause a serious problem in terms of continuing pregnancy. Here, we present a parturient with severe lumbago who underwent resection of a spinal tumor. A 42-year-old parturient at 26 weeks of gestation presented with acute onset of severe pain in the lumbar region and lower extremities. Magnetic resonance imaging revealed an intraspinal tumor from L4 to L5. Although sciatic nerve block and epidural anesthesia were performed to relieve the pain, their analgesic effects were insufficient. Since the continuation of pregnancy was difficult because of the severe pain, she was scheduled for the resection of the tumor under general anesthesia at 28 weeks gestation. Fetal heart monitoring was used to evaluate abnormal heart rate patterns in the operating room. In order to avoid a decrease in uteroplacental blood flow, the intraoperative systolic blood pressure was maintained at 100 mmHg or more and end-tidal carbon dioxide was maintained at 35-40 mmHg. She was placed on left lateral position to avoid aortocaval compression, and surgery was uneventfully completed. The pain was relieved after surgery, and the parturient could continue the pregnancy. She under- went cesarean section at 40 weeks of gestation, and gave birth to a healthy baby.

[Improvement of consciousness by administration of flumazenil in a patient with unexpectedly delayed emergence from general anesthesia].

A 64-year-old woman was scheduled for the removal of hepatic cystadenoarcinoma. The preoperative examination did not reveal any neurological disorders. Anesthesia was induced with midazolam (5 mg) and remifentanil (0.1.ag x kg-1 x min-1) and the trachea was intubated following administration of rocuronium. Anesthesia was maintained with propofol (1.2-4.0 mg x kg-1 x hr-1), remifentanil (0.1-0.4microg kg 1 x min-1), and rocuronium (10 mg) as needed. The dose of propofol was controlled so that bispectral index (BIS) ranged between 40 and 60 during surgery. The duration of surgery was 10 hr 29 min. Administration of propofol and remifentanil was terminated at the end of surgery. After confirmation of T2 appearance by train-of-four stimuli, sugammadex (2 mg x kg 1) was intravenously administered. Although respiratory rate and tidal volume were 12-18 breaths x min-1 and 350-450 ml, respectively, she remained unconsciousness at about 40 of BIS. We could not find any factors associated with delayed emergence from anesthesia. Flumazenil (0.5 mg) was administered intravenously 90 min after termination of anesthesia. Two min later, she became fully awake and alert with increase in BIS (above 90). Laboratory examination showed that the plasma concentrations of propofol, midazolam, and its active metabolite alpha-hydroxymidazolam before administration of flumazenil were within the range considered to have no sedative effects. From experience of this case, administration of flumazenil may be beneficial for improvement in consciousness in cases with unexpectedly delayed emergence from anesthesia.