Massive pulmonary embolism in Klippel-Trenaunay syndrome after leg raising: A case report.

BACKGROUND: Klippel-Trenaunay syndrome (KTS) is a rare congenital disorder characterized by a combination of capillary malformations, soft-tissue or bone hypertrophy, and varicose veins or venous malformations. The syndrome predisposes patients to hypercoagulable states, including venous thromboembolism and pulmonary embolism (PE). CASE SUMMARY: A 12-year-old girl with KTS was scheduled excision of verrucous hyperkeratosis in the left foot and posterior aspect of the left leg and left thigh and excision of a cutaneous hemangioma in the right buttock. After induction, the surgeon elevated the patient's leg for sterilization, whereupon she experienced a massive PE and refractory cardiac arrest. Extracorporeal membrane oxygenation (ECMO) was performed after prolonged resuscitation, and she had a return of spontaneous circulation. After this episode, the patient was discharged without any neurologic complications. CONCLUSION: The mechanism of PE, a lethal disease, involves a preexisting deep vein thrombosis that is mechanically dislodged by compression or changing positions and travels to the pulmonary artery. Therefore, patients predisposed to PE should be prescribed prophylactic anticoagulants. If the patient has unstable vital signs, resuscitation should be started immediately, and extracorporeal cardiopulmonary resuscitation should be considered in settings with existing ECMO protocols, expertise, and equipment. Awareness of PE in patients with KTS while leg raising for sterilization is critical.

Alleviating Bone Cancer-induced Mechanical Hypersensitivity by Inhibiting Neuronal Activity in the Anterior Cingulate Cortex.

BACKGROUND: The anterior cingulate cortex (ACC) is a brain region that has been critically implicated in the processing of pain perception and modulation. While much evidence has pointed to an increased activity of the ACC under chronic pain states, less is known about whether pain can be alleviated by inhibiting ACC neuronal activity. METHODS: The authors used pharmacologic, chemogenetic, and optogenetic approaches in concert with viral tracing technique to address this issue in a mouse model of bone cancer-induced mechanical hypersensitivity by intratibia implantation of osteolytic fibrosarcoma cells. RESULTS: Bilateral intra-ACC microinjections of γ-aminobutyric acid receptor type A receptor agonist muscimol decreased mechanical hypersensitivity in tumor-bearing mice (n =10). Using adenoviral-mediated expression of engineered Gi/o-coupled human M4 (hM4Di) receptors, we observed that activation of Gi/o-coupled human M4 receptors with clozapine-N-oxide reduced ACC neuronal activity and mechanical hypersensitivity in tumor-bearing mice (n = 11). In addition, unilateral optogenetic silencing of ACC excitatory neurons with halorhodopsin significantly decreased mechanical hypersensitivity in tumor-bearing mice (n = 4 to 9), and conversely, optogenetic activation of these neurons with channelrhodopsin-2 was sufficient to provoke mechanical hypersensitivity in sham-operated mice (n = 5 to 9). Furthermore, we found that excitatory neurons in the ACC send direct descending projections to the contralateral dorsal horn of the lumbar spinal cord via the dorsal corticospinal tract. CONCLUSIONS: The findings of this study indicate that enhanced neuronal activity in the ACC contributes to maintain bone cancer-induced mechanical hypersensitivity and suggest that the ACC may serve as a potential therapeutic target for treating bone cancer pain.

Impairment of long-term depression in the anterior cingulate cortex of mice with bone cancer pain.

The anterior cingulate cortex (ACC) has been shown to play an important role in pain-related perception and chronic pain. However, little is known about the molecular mechanisms involved. To address this issue, we analyzed excitatory synaptic transmission and long-term synaptic plasticity in layer II/III pyramidal neurons within the rostral ACC (rACC) from mice with bone cancer pain induced by intra-tibia implantation of osteolytic fibrosarcoma cells. Ex vivo whole-cell patch-clamp recordings from rACC neurons showed no significant alterations in presynaptic glutamate release probability and postsynaptic α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor-mediated synaptic responses in mice with bone cancer pain. However, mechanical allodynia occurred in conjunction with decreased N-methyl-d-aspartate (NMDA)/AMPA ratio of synaptic currents elicited in bilateral rACC neurons. In addition, the induction of NMDA receptor-dependent long-term depression (LTD) at rACC synapses was impaired in rACC neurons of tumor-bearing mice. Western blot analysis revealed a significant decrease in the levels of NR1, NR2A, and NR2B subunits of NMDA receptors in the rACC under bone cancer pain condition. No significant changes in overall mRNA levels for any of the NMDA receptor subunits or calpain activity were observed in the rACC of tumor-bearing mice. These results indicate that tumor-induced injury or remodeling of primary afferent sensory nerve fibers that innervate the tumor-bearing bone may cause a persistent decrease in NMDA receptor expression in rACC neurons, resulting in a loss of LTD induction, thereby leading to long-term alterations of rACC activity and creating exaggerated pain behaviors.

Factors associated with vomiting in orthopedic patients receiving patient-controlled epidural analgesia.

BACKGROUND: Although patient-controlled epidural analgesia (PCEA) can effectively relieve postoperative pain in orthopedic patients, some adverse effects are still troublesome. We conducted this study to survey the possible risk factors related to vomiting induced by PCEA. METHODS: This retrospective study was conducted to review orthopedic patients receiving postoperative PCEA. The agent for PCEA was bupivacaine prepared as a 0.1% solution with added fentanyl (1 microg/mL). Patients' characteristics including demographic data and types of surgical procedures were collected. All patients were dichotomized into vomiting and non-vomiting groups and subgroup comparisons were also performed. Stepwise logistic regression analyses were conducted to determine significant factors associated with vomiting in these patients. RESULTS: There were 320 patients (111 men, 209 women) included in the analysis. No significant differences in demographic data were noted between the groups except in sex distribution. Factors related to surgery, anesthesia and PCEA were similar between groups (p > 0.05 in all). The incidence of vomiting for orthopedic patients receiving PCEA was about 9.7% (12.4% for female, 4.5% for male). After stepwise model selection, we found female sex was the only risk factor of vomiting. The odds ratio of vomiting for female gender was 3 (95% confidence interval, 1.1-8.1). General anesthesia was not associated with vomiting in these patients. CONCLUSION: Our study demonstrated the risk factor associated with vomiting for orthopedic patients receiving PCEA was female sex. Other demographic variables and factors related to surgery or anesthesia did not have an influence on vomiting.

Clindamycin-induced anaphylactic shock during general anesthesia.

Clindamycin-related anaphylactic reaction is rarely reported. We report a male patient with buccal cancer who was undergoing radical neck dissection when life-threatening anaphylactic shock developed soon after intravenous infusion of clindamycin. Immediate cardiopulmonary resuscitation was performed, and the patient recovered uneventfully. Perioperative anaphylactic shock is a serious problem due to the difficulty of judgment and potentially disastrous outcome. Immediate diagnosis and halting of drug infusion should be the first actions taken.

Correlations between patient-controlled epidural analgesia requirements and individual characteristics among gynecologic patients.

BACKGROUND: Patient-controlled epidural analgesia (PCEA) has been used widely to relieve postoperative pain. Although many studies have demonstrated the safety and effectiveness of PCEA, the relationship between patients' characteristics and requirements of PCEA has not been investigated yet. We conducted this retrospective study to explore the correlations between total PCEA demand and patients' characteristics. METHODS: We collected data from patients aged from 20 to 65, receiving gynecologic operations and consenting to epidural analgesia. All patients used postoperative PCEA for at least 3 days. An analgesic solution of bupivacaine (0.0625%) and morphine (0.02 mg/mL) was prepared for PCEA in all patients. The total PCEA consumption was recorded at the end of the 3-day course. Stepwise regression analysis was conducted to sort out influential factors which could determine the total PCEA demand. RESULTS: There were 170 patients (81 benign and 89 malignant cases) included in the analysis. Significant differences existed in age and total PCEA requirement between different disease patterns. The stepwise regression model selection showed that disease patterns, body mass index (BMI) and age were most significant determinants of total PCEA demand. The R and adjusted R square values of the final selected model are 0.339 and 0.099, respectively. The comparison between the standardized regression coefficient of BMI and age suggested that the influence of BMI is greater than that of age. CONCLUSIONS: Disease patterns, BMI and age are associated with total PCEA requirements. Gynecologic patients receiving procedures for malignant diseases consumed more PCEA solution than benign cases. Height is not associated with total PCEA demand. There is a close correlation between BMI and PCEA consumption but age is a negative correlate.

Occurrence of the Bezold-Jarisch reflex during Cesarean section under spinal anesthesia--a case report.

We report a 35-year-old parturient with gestational diabetes mellitus (GDM) history who sustained a nearly fatal Bezold-Jarisch reflex during Cesarean section under spinal anesthesia. A high spinal block combined with acute massive hemorrhage may produce life-threatening Bezold-Jarisch reflex which should be treated prophylactically and aggressively during surgery. Additionally, the autonomic disturbance associated with GDM might exaggerate the reflex in this episode. The patient survived after successful resuscitation and was discharged without any sequela.