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We report an unusual case of a dural arteriovenous fistula (dAVF) presenting as acute neck pain and quadripareis in a 55-year-old previously healthy man. Imaging was suspicious for cervicomedullary venous thrombosis and angiography failed to show evidence of arteriovenous malformation or dAVF. The patient was started on warfarin for a presumed cervicomedullary venous thrombosis and there was a significant clinical improvement. However, 3 weeks later, the symptoms recurred and repeat angiography revealed a dAVF fed by a posterior branch of the left middle meningeal artery draining into the posterior fossa vein. We postulated that warfarin caused recanalisation of the previously thrombosed venous pouch allowing for angiographic discovery and treatment of the dAVF. The dAVF was embolised with onyx resulting in the complete obliteration of the dAVF and symptomatic improvement. Although rare, some dAVF can be concealed or disappear on angiography due to thrombosis of the draining vein and warfarin can lead to recanalisation. [ABSTRACT FROM AUTHOR]

Objectives We sought to identify if preoperative schwannoma magnetic resonance imaging (MRI) intensities might predict intraoperative consistency. We then determined whether consistency correlated with facial nerve outcomes. Design Operative reports from 2000 to 2010 were searched for tumor description as either soft and/or suckable or firm and/or fibrous. Preoperative T1 and T2 sequences were then reviewed to identify intensities relative to gray matter. Facial nerve function was recorded at the time of most recent follow-up. Results Forty-six patients were included. No tumors were T1 hyperintense. Soft and firm schwannomas were equally likely to be T1 hypointense. On T2 sequences, however, soft schwannomas were more likely to be hyperintense (88% versus 14%, p < 0.005) whereas firm schwannomas were more likely to be hypointense (86% versus 6%, p < 0.005). There was a tendency for firm schwannomas to have worse facial nerve outcomes (43% versus 19%, p = 0.14). Conclusions Prediction of vestibular schwannoma intraoperative consistency based on T2 intensity seems promising. Furthermore, though not statistically significant, in this small pilot study firm schwannomas tended to have worse facial nerve outcomes. This potential ability to predict consistency and its correlation with facial nerve outcome may assist the surgeon in preoperative planning and patient counseling, though further data needs to be accumulated. [ABSTRACT FROM AUTHOR]

We present a case of an intramedullary melanotic schwannoma (IMS) of the thoracic spinal cord. To our knowledge, this is the seventh reported case of an IMS of the central nervous system. Schwannomas are benign nerve sheath tumors of neural crest origin composed entirely of well differentiated Schwann cells that typically occur in peripheral nerves. Both the intramedullary location and the melanotic component of the reported lesion make it exceedingly rare. We will present our case, theories as to the origin of these tumors, clues in radiographic identification, and current clinical follow-up recommendations. [ABSTRACT FROM AUTHOR]

Background: Meningioma firmness is a critical factor that influences ease of resection and risk, notably when operating on tumors intimate with neurovascular structures such as the mesial sphenoid wing. This study develops a predictive tool using preoperative magnetic resonance imaging (MRI) characteristics to determine meningioma consistency. Methods: 101 patients with intracranial meningioma (50 soft/51 firm) were included. MRI characteristics of 38 tumors (19 soft/19 firm) were retrospectively reviewed to identify preoperative imaging features that were then correlated with intraoperative description of the tumor as either “soft and/or suckable” or “firm and/or fibrous.” Criteria were developed to predict consistency and then blindly applied to the remaining 63 meningiomas (31 soft/32 firm). Results: The overall sensitivities for detecting soft and firm consistency were 90% and 56%, respectively (95% CI = 73–97% and 38–73%; P < 0.001). Compared to gray matter, meningiomas that were T2 hypointense were almost always firm. Soft meningiomas were hyperintense on T2 and hypointense on T1. Soft meningiomas were slightly larger and less likely to be associated with edema. There was a slight preponderance of firm meningiomas in the infratentorial compartment. Grade of meningioma was not predictive. Contrast enhancement, diffusion restriction, changes in overlying bone, intratumoral cysts, and angiographic features were not predictable. Conclusions: This tool using T1 and T2 series predicts meningioma consistency. Such knowledge should assist the surgeon in preoperative planning and counseling. [ABSTRACT FROM AUTHOR]

Objective: To test the hypothesis that ma huang induces a pressor response in the pulmonary vascular bed of the cat and identify the alpha (1)-adrenoceptor subtype pathway(s) involved in the mediation or modulation of these effects. Design: Prospective vehicle controlled study. Setting: University research laboratory. Subjects: Intact chest preparation; adult mongrel cats. Interventions: In separate experiments, the effects of phentolamine, the alpha-adrenergic antagonist; prazosin, a selective alpha (1)-adrenoceptor antagonist; BMY 7378, a selective alpha (1) D-subtype adrenoceptor antagonist; 5-methyl-urapidil, the selective alpha (1)A-subtype adrenoceptor antagonist; and chloroethylclonidine, an alpha (1)B-subtype and (1) D-subtype adrenoceptor antagonist, were investigated on pulmonary arterial responses to ma huang and other agonist agents in the pulmonary vascular bed of the cat. Measurements and Main Results: Under constant flow conditions, lobar arterial perfusion pressure and systemic pressure were continuously monitored, electronically averaged, and permanently recorded. In the feline vascular bed of the isolated left lower lobe, ma huang induced a dose-dependent vasopressor response that was not significantly attenuated following administration of 5-methyl-urapidil. However, the responses to Ma huang were significantly reduced after administration of phentolamine, prazosin, BMY 7378, and chloroethylclonidine. Conclusions: The results of the present study suggest that ma huang has potent vasopressor activity in the pulmonary vascular bed of the cat and that this response may be mediated or modulated by both alpha (1)B-subtype and (1)D-subtype adrenoceptor sensitive pathways [ABSTRACT FROM AUTHOR]

Aim: In the present study, we describe the effects of deep tissue massage on systolic, diastolic, and mean arterial blood pressure. Materials and methods: The study involved 263 volunteers (12 males and 88 females), with an average age of 48.5. Overall muscle spasm/muscle strain was described as either moderate or severe for each patient. Baseline blood pressure and heart rate were measured via an automatic blood pressure cuff. Twenty-one (21) different soothing CDs played in the background as the deep tissue massage was performed over the course of the study. The massages were between 45 and 60 minutes in duration. The data were analyzed using analysis of variance with post-hoc Scheffe's F-test. Results: Results of the present study demonstrated an average systolic pressure reduction of 10.4 mm Hg ( p < 0.06), a diastolic pressure reduction of 5.3 mm Hg ( p < 0.04), a mean arterial pressure reduction of 7.0 mm Hg ( p < 0.47), and an average heart rate reduction of 10.8 beats per minute ( p < 0.0003), respectively. Conclusions: Additional scientific research in this area is warranted. [ABSTRACT FROM AUTHOR]

Objective: To test the hypothesis that norepinephrine induces a pressor response in the pulmonary vascular bed of the cat and identify the alpha-(1)adrenoceptor subtypes involved in the mediation or modulation of these effects.Design: Prospective vehicle controlled study.Setting: University research laboratory.Subjects: Intact chest preparation, adult mongrel cats.Interventions: In separate experiments, the effects of 5-methyl-urapidil, a selective alpha-(1)A-subtype adrenoceptor antagonist, chloroethylclonidine, an alpha-(1)B-subtype and -(1)D-subtype adrenoceptor antagonist, and BMY 7378, the selective alpha-(1)D-subtype adrenoceptor antagonist, were investigated on pulmonary arterial responses to norepinephrine and other agonists in the pulmonary vascular bed of the cat.Measurements and Main Results: The systemic pressure and lobar arterial perfusion pressure were continuously monitored, electronically averaged, and permanently recorded. In the feline pulmonary vascular bed of the isolated left lower lobe, norepinephrine induced a dose-dependent vasoconstrictor response that was not significantly altered after administration of BMY 7378. However, the responses to norepinephrine were significantly attenuated following administration of 5-methyl-urapidil and chloroethylclonidine.Conclusions: The results of the present study suggest that norepinephrine has potent vasopressor activity in the pulmonary vascular bed of the cat and that this response may be mediated or modulated by both alpha-(1)A-subtype and -(1)B-subtype adrenoceptor sensitive pathways. [ABSTRACT FROM AUTHOR]

Objective: To test the hypothesis that St. John's wort induces a depressor response in the feline pulmonary vascular bed and identify the pathways involved in the mediation or modulation of these effects. Design: Prospective vehicle controlled study. Setting: University research laboratory. Subjects: Intact chest preparation; adult mongrel cats. Interventions: In separate experiments, the effects of L-N5-(1-Iminoethyl) ornithine hydrochloride (L-NIO), a nitric oxide synthase inhibitor, glibenclamide, an ATP-sensitive K+ channel blocker, meclofenamate, a non-selective cyclo-oxygenase (COX) inhibitor, nicardipine, a calcium channel blocker, bicuculline, a GABAA receptor antagonist, and saclofen, a GABAB antagonist, were investigated on pulmonary arterial responses of St. John's wort (SJW), pinacidil, an ATP-sensitive K+ channel activator, bradykinin, an inducer of nitric oxide synthase, 3-aminopropyl (methyl) phosphinic acid, hydrochloride (SKF-97541), a GABAB receptor agonist and muscimol, a GABAA receptor agonist. Measurements and Main Results: Lobar arterial perfusion pressure and systemic pressure were continuously monitored, electronically averaged and permanently recorded. Under elevated tone conditions in the isolated left lower lobe vascular bed of the cat, SJW induced a dose-dependent vasodepressor response that was not significantly altered after administration of L-NIO, glibenclamide, meclofenamate or saclofen. Responses to SJW were significantly reduced after administration of either nicardipine or bicuculline. When the calcium channel blocker nicardipine was administered in addition to the GABA blocker bicuculline, there was near complete attenuation of the SJW-induced vasodepressor responses. Conclusions: The results of the present study suggest that SJW has potent vasodepressor activity in the pulmonary vascular bed of the cat and that this response is mediated or modulated by both a calcium ... [ABSTRACT FROM AUTHOR]

Leptomeningeal carcinomatosis (LC) after metastasis of breast cancer is a rare occurrence with potentially devastating complications. Treatment options are limited, and there is a lack of literature on this topic. We report the case of a 38-year-old woman with estrogen/progesterone receptor negative (ER/PR-), human epidermal growth factor receptor 2 positive (HER2+) invasive ductal carcinoma of the left breast who underwent bilateral mastectomies with axillary lymph node dissection and chemotherapy treatment. The patient returned 11 months later with persistent headaches. Imaging and resection found cerebellar metastasis of the breast carcinoma. The brain metastasis was treated with further chemotherapy and stereotactic radiosurgery. Follow-up imaging showed the development of small lesions outside the radiation site. Metabolic studies were performed to determine if the new lesions were due to tumor recurrence or radiation necrosis, but the studies were inconclusive as to the etiology of these lesions. The patient later developed LC that was successfully treated with full resolution of the disease using intrathecal trastuzumab. There are currently no consensuses on treatment guidelines for treating LC. Here, we demonstrate successful treatment of LC from an ER/PR-, HER2+ breast carcinoma with intrathecal trastuzumab., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2022, Smith et al.)

The authors present the case of a 56-year-old right hand-dominant woman who was referred for chronic neck pain and a second opinion regarding a cervical lesion. The patient's pain was localized to the subaxial spine in the midline. She reported a subjective sense of intermittent left arm weakness manifesting as difficulty manipulating small objects with her hands and fingers. She also reported paresthesias and numbness in the left hand. Physical and neurological examinations demonstrated no abnormal findings except for a positive Tinel sign over the left median nerve at the wrist. Electromyography demonstrated bilateral carpal tunnel syndrome with no cervical radiculopathy. Cervical spine imaging demonstrated multilevel degenerative disc disease and a pneumatocyst of the C-5 vertebral body. The alignment of the cervical spine was normal. A review of the patient's cervical imaging studies obtained in 1995, 2007, 2008, and 2010 demonstrated that the pneumatocyst was not present in 1995 but was present in 2007. The lesion had not changed in appearance since 2007. At an outside institution, multilevel fusion of the cervical spine was recommended to treat the pneumatocyst prior to evaluation at the authors' institution. The authors, however, did not think that the pneumatocyst was the cause of the patient's neck pain, and cervical pneumatocysts typically have a benign course. As such, the authors recommended conservative management and repeated MR imaging in 6 months. Splinting was used to treat the patient's carpal tunnel syndrome.

Object: Transnasal endoscopic (TNE) approaches have been proposed for the resection of anterior cranial base meningiomas. The purpose of this article was to evaluate the results of endoscopic resection of anterior cranial fossa meningiomas by reviewing available published data in addition to the authors' experience with 13 cases., Methods: The literature was searched via OVID to identify all available disaggregate data pertaining to anterior fossa meningiomas treated primarily by TNE. In addition, the authors reviewed the records of a personal series of 13 patients who underwent TNE removal of parasellar meningiomas through a pure TNE approach., Results: Meta-analysis from studies included a total of 69 patients with adequate disaggregated data to summarize. Mean age (± SD) at surgery was 53.3 ± 13.0 years (range 27-80 years); 78% of the patients were women. Tumor size was skewed toward smaller lesions, with a mean volume of 24.4 ± 2.9 cm(3). Intraoperative impressions were of gross-total resection in 76% of cases. The most common complication reported was CSF leakage, occurring in 32% of the cases (22 of 69). The rate of CSF leakage was not affected by size (p = 0.52), location of tumor (p = 0.9), or age (p = 0.56). There was 1 death overall. The mean duration of follow-up was 21 ± 18 months., Conclusions: Transnasal endoscopic resection of anterior cranial base meningiomas is feasible in selected cases. Reported resection rates are adequate, although the follow-up in the reported series is too short (mean 21 months) to make definitive conclusions regarding the long-term effectiveness. Cerebrospinal fluid leakage is a common complication, although it appears not to be associated with additional morbidity except for the need for reoperation. Long-term results are necessary before considering TNE resection as a valid alternative, in selected cases, to the more established transcranial techniques.

Objective: There are extensive data on roles of cyclooxygenase 1 (COX 1) and cyclooxygenase 2 (COX 2) enzymes in temperature, coagulation, and inflammatory modulation. There is little known of the function of these enzymes in regulating tone in pulmonary vasculature. The purpose of this investigation was to elucidate the roles of COX 1 and 2 enzymes in the feline pulmonary vascular bed., Design: Prospective vehicle controlled study., Setting: University research laboratory., Subjects: Intact chest preparation; adult mongrel cats., Interventions: The effects of intravascular administration of U46619, angiotensin II, prostaglandin E1 (PGE1), arachidonic acid, and norepinephrine, were analyzed before and after intravascular administration of selective COX enzyme inhibitors., Measurements and Main Results: Because lobar arterial flow is constant in these experiments, changes in lobar pressure represent changes in pulmonary arterial resistance. Under constant flow conditions, lobar arterial and systemic pressures were continuously monitored, electronically averaged, and recorded. In the isolated left lower lobe of the feline lung bed, U46619, angiotensin II, arachidonic acid, and norepinephrine induced a dose-dependent vasoconstrictor response. PGE1 induced a dose-dependent vasodepressor response. After administration of the COX 1 inhibitor SC 560, the arachidonic acid-induced vasopressor responses were significantly attenuated while U46619, angiotensin II, and norepinephrine-induced vasopressor, and PGE1-induced vasodepressor responses were not significantly altered. After administration of the COX 2 inhibitor nimesulide, both the PGE 1 vasodepressor responses and arachidonic acid-induced vasopressor responses were significantly decreased while the U46619, angiotensin II, and norepinephrine-induced vasopressor responses were not significantly attenuated., Conclusions: The results of the study indicate that PGE1 has potent vasodepressor effects in the feline lung bed and this response is mediated by COX 2 pathways. The data also suggest that arachidonic acid has potent vasopressor activity in the feline pulmonary vascular bed and this response is mediated by both COX 1 and COX 2 sensitive pathways.

Sepsis and shock are severe conditions that, when together, may cause multiple organ failure. The anesthesiologist must be able to take a careful history and physical, as well as be aware that additional tests are necessary to assess the patient status, as preoperative systemic blood pressure is not indicative of adequate volume status. In preparation for surgery, one must anticipate dysfunction and have adequate blood products and antibiotic at hand. Ketamine is notable for induction in these patients because it is less likely to decrease systemic vascular resistance too quickly. One must not take this lightly, as death may ensue if proper management is not taken.

The objective of this study was to test the hypothesis that fentanyl induces a depressor response in the pulmonary vascular bed of the cat and to identify the receptors involved in the mediation or modulation of these effects. The authors conducted a prospective vehicle-controlled study at a university research laboratory using intact chest preparation in adult mongrel cats. In separate experiments, the effects of diphenhydramine (histamine receptor blocker), glibenclamide (ATP-sensitive K+ channel blocker), L-N5-(1-Iminoethyl) ornithine hydrochloride (L-NIO) (nitric oxide synthase inhibitor), nimesulide (selective cyclooxygenase [COX]-2 inhibitor), and naloxone (opiate receptor antagonist) were investigated on pulmonary arterial responses to fentanyl and other agonists in the pulmonary vascular bed of the cat. The systemic pressure and lobar arterial perfusion pressure were continuously monitored, electronically averaged, and recorded. In the feline pulmonary vascular bed of the isolated left lower lobe, fentanyl induced a dose-dependent vasodepressor response that was not significantly altered after administration of glibenclamide, L-NIO, and nimesulide. However, the responses to fentanyl were significantly attenuated after administration of diphenhydramine and naloxone. The results of the present study suggest that fentanyl has potent vasodepressor activity in the pulmonary vascular bed of the cat and that this response may be mediated or modulated by both histaminergic and opiate receptor sensitive pathways.

Congestive heart failure (CHF) is increasingly being recognized as a health problem in the United States. It is estimated that the lifetime risk for CHF is 1 in 5. The clinical anesthesiologist can expect to see several cases involving patients suffering from CHF. Because of the danger associated with surgery in a patient with CHF, a thorough knowledge of the disorder and the potential effects on the delivery of anesthetics must be considered. In addition, knowledge of the disease process and its manifestations is required for smooth guidance of the patient through the perioperative period. The understanding of current pharmacotherapies, surgical procedures and their implications related to interactions with anesthetics are all discussed.

This study was designed to test the hypothesis that kava kava induces a depressor response in the pulmonary vascular bed of the cat and to identify the pathways involved in the mediation or modulation of these effects. In separate experiments, the effects of L-N5-(1-iminoethyl)ornithine hydrochloride (L-NIO), a nitric oxide synthase inhibitor, glibenclamide, an ATP-sensitive K+ channel blocker, meclofenamate, a nonselective cyclooxygenase inhibitor, nicardipine, a calcium channel blocker, bicuculline, a gamma-aminobutyric acid (GABA)A receptor antagonist, and saclofen, a GABAB antagonist, were investigated on pulmonary arterial responses to kava kava (kava), pinacidil, an ATP-sensitive K+ channel activator, bradykinin, an inducer of nitric oxide synthase, 3-aminopropyl(methyl)phosphinic acid hydrochloride (SKF-97541), a GABAB receptor agonist, and muscimol, a GABAA receptor agonist. Lobar arterial perfusion pressure and systemic pressure were continuously monitored, electronically averaged, and recorded. Under elevated tone conditions in the isolated left lower lobe of the feline vascular bed, kava induced a dose-dependent vasodepressor response that was not significantly altered after administration of L-NIO, glibenclamide, meclofenamate, or saclofen. Responses to kava were significantly reduced after administration of either nicardipine or bicuculline. When the calcium channel blocker nicardipine was administered in addition to the GABA blocker bicuculline, there was near complete attenuation of the kava-induced vasodepressor responses. The results of this investigation suggest that kava has potent vasodepressor activity in the feline lung bed and that this response is mediated or modulated by both a calcium channel- and GABA receptor-sensitive pathway.

In this investigation we sought to identify the role of remifentanil in the feline pulmonary vascular bed. Using adult mongrel cats in separate experiments, the effects of glibenclamide (adenosine triphosphate-sensitive K+ channel blocker), diphenhydramine (histamine H(1)-receptor antagonist), L-N5-(1-Iminoethyl) ornithine hydrochloride (nitric oxide synthase inhibitor), and naloxone (opioid receptor antagonist) were investigated in pulmonary arterial responses to remifentanil (opioid agonist), pinacidil (adenosine triphosphate-sensitive K+ channel activator), and bradykinin (nitric oxide synthase inducer). Under increased tone conditions in the isolated left lower lobe vascular bed of the cat, remifentanil induced a dose-dependent vasodepressor response that was not significantly altered after administration of glibenclamide and L-N5-(1-Iminoethyl) ornithine hydrochloride. Responses to remifentanil were significantly attenuated after administration of diphenhydramine and naloxone. The results suggest that remifentanil has potent vasodepressor activity in the feline pulmonary vascular bed and that these responses are mediated by histamine and opioid receptor sensitive pathways.

MOF or MOSF is a serious condition that represents a leading cause of death in critically ill or injured patients. It commonly begins as a result of injury, widespread inflammation, infection, shock or a combination of the above. Progression from SIRS to MOSD and on to MOF can occur within days. Therefore, careful systemic monitoring of respiratory, cardiovascular central nervous, renal, hepatic, gastrointestinal and hematologic function is vital. Although certain mechanisms such as decreased O2 supply to cells, neutrophil priming, increased TNF-alpha, interleukins, and NO have been implicated, an effective treatment for this condition remains elusive. The anesthesiologist and critical care professionals must work together to effectively evaluate and treat the MOF patient.

In this investigation, we sought to identify the role of gamma-aminobutyric acid (GABA)(A) and GABA(B) receptors in the feline pulmonary vascular bed. Using adult mongrel cats and in separate experiments, we investigated the effects of l-N(5)-(1-iminoethyl) ornithine hydrochloride (l-NIO) (a nitric oxide synthase inhibitor), glibenclamide (an adenosine triphosphate (ATP)-sensitive K(+) channel blocker), meclofenamate (a nonselective cyclooxygenase inhibitor), bicuculline (a GABA(A) receptor antagonist), and saclofen (a GABA(B) receptor antagonist) on pulmonary arterial responses to pinacidil (an ATP-sensitive K(+) channel activator), bradykinin (a nitric oxide synthase inducer), muscimol (a GABA(A) receptor agonist), and 3-aminopropyl(methyl)phosphinic acid, hydrochloride (SKF-97541; a GABA(B) receptor agonist). Under increased tone conditions in the isolated left lower lobe vascular bed of the cat, muscimol induced a dose-dependent vasodepressor response that was not significantly altered after the administration of l-NIO, glibenclamide, meclofenamate, and saclofen. SKF-97541-induced vasodepression was not significantly attenuated after the administration of l-NIO, meclofenamate, and bicuculline. Responses to SKF-97541 were significantly attenuated after the administration of glibenclamide and saclofen. Responses to muscimol were significantly reduced after the administration of bicuculline. The results suggest that muscimol and SKF-97541 have potent vasodepressor activity in the feline pulmonary vascular bed and that these responses are modulated by, respectively, GABA(A) and GABA(B) receptor-sensitive pathways. Further, SKF-97541-induced vasodepression is mediated or modulated by an ATP-sensitive K(+) channel.

Tissue Doppler Imaging (TDI) provides information on systolic function through its systolic mitral annulus velocity wave (Sm), reflecting the peak velocity of shortening of the myocardial fibers oriented in the longitudinal direction. In this study, we evaluated the effect of load changes on Sm. Forty-two cardiac surgical patients with left ventricular ejection fraction >60% were consecutively evaluated. In 24 patients, load was changed with an IV bolus of phenylephrine (50-100 microg) or nitroglycerine (300-500 microg); in 18 patients, preload was changed with a rapid infusion of 500 mL of a gelatin solution. The sample volume of TDI was placed at the lateral side of the mitral annulus in the mid-esophageal 4-chamber view. Changing loading conditions with phenylephrine or nitroglycerine had no effect on Sm; the increase of preload in 18 patients resulted in a statistically significant increase of Sm (baseline, 8.4 +/- 2.6 cm/s; after increase of preload, 9.6 +/- 2.5 cm/s; P = 0.001). We conclude that Sm is dependent on changes in preload obtained by volume loading and cannot be recommended as an index of ventricular contractile performance in critically ill patients where significant changes in ventricular filling occur.