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Let M be a locally rotationally symmetric spacetime with at least one of the rotation or spatial twist being non-zero. It is proved that M cannot admit a non-minimal marginally trapped tube of the form χ=X(t).

Let M be a locally rotationally symmetric spacetime, and ξ a a conformal Killing vector for the metric on M , lying in the subspace spanned by the unit timelike direction and the preferred spatial direction, and with non-constant components. Under the assumption that the divergence of ξ a has no critical point in M , we obtain the necessary and sufficient condition for ξ a to generate a conformal Killing horizon. It is shown that ξ a generates a conformal Killing horizon if and only if either of the components (which coincide on the horizon) is constant along its orbits. That is, a conformal Killing horizon can be realized as the set of critical points of the variation of the component(s) of the conformal Killing vector along its orbits. Using this result, a simple mechanism is provided by which to determine if an arbitrary vector in an expanding LRS spacetime is a conformal Killing vector that generates a conformal Killing horizon. In specializing the case for which ξ a is a special conformal Killing vector, provided that the gradient of the divergence of ξ a is non-null, it is shown that LRS spacetimes cannot admit a special conformal Killing vector field, thereby ruling out conformal Killing horizons generated by such vector fields.

A bstract We investigate the charged Vaidya spacetime with conformal symmetry by classifying the horizons and finding its connection to Hawking temperature. We find a conformal Killing vector whose existence requires the mass and electric charge functions to be proportional, as well as linear in time. Solving the Killing equations for the conformally transformed metric from the linear charged Vaidya metric yields the required form of the conformal factor. From the vanishing of the norm of the conformal Killing vector, we find three conformal Killing horizons which, under the transformation, are mapped to the Killing horizons of the associated static spacetime, if the spherical symmetry is maintained. We find that the conformal factor is not uniquely determined, but can take any function of the ratio of the radial coordinate to the dynamical mass. As an example, we illustrate a static spacetime with our choice of the conformal factor and explicitly show that the surface gravity of the conformal Killing horizons, which is conformally invariant, yield the expected Hawking temperature in the static spacetime. This static black hole spacetime contains a cosmological horizon, but it is not asymptotically de Sitter. We also investigate the case when the mass parameter is equal to the constant electric charge. While in this case the standard pair of horizons, the loci of the time component of the metric, degenerate, the conformal Killing horizons do not degenerate. This therefore leads to a non-zero Hawking temperature in the associated static spacetime.

Although the stellate ganglion is located anteriorly to the first rib, anesthetic block is routinely performed at the C6 level. Ultrasonography allegedly improves accuracy of needle placement and spread of injectate. The technique is relatively new, and the optimal approach has not been determined. Moreover, the location of the cervical sympathetic trunk relative to the prevertebral fascia is debatable. Three-dimensional sonography was performed on 10 healthy volunteers, and image reconstruction was completed. On the basis of analysis of pertinent anatomy, a lateral trajectory for needle placement was simulated. Accuracy was tested by injection of methylene blue in cadavers. A clinical validation study was then conducted. A block needle was inserted according to the predetermined lateral path, and 5 mL of a mixture of bupivacaine and iohexol was injected. Spread of the contrast agent was verified fluoroscopically. Image reconstruction revealed that the cervical sympathetic trunk is located posterolaterally to the prevertebral fascia on the surface of the longus colli muscle. The mean anteroposterior width of the muscle at the C6 level was 11 mm. The lateral approach does not interfere with any visceral or nerve structures. Anatomic dissection in cadavers confirmed entirely subfascial spread of the dye and staining of the sympathetic trunk. The contrast agent spread was seen in all patients between the C4 and T1 levels in a typical prevertebral pattern. This study revealed that, at the C6 level, the cervical sympathetic trunk lies entirely subfascially. Subfascial injection via the lateral approach ensures reliable spread of a solution to the stellate ganglion.

Cardiovascular magnetic resonance-feature tracking (CMR-FT) is a novel quantitative objective noninvasive technique in the assessment of myocardial deformation. The purpose of that study was to assess the capability of the CMR-FT in the detection of myocardial ischemia and viability. We investigated 30 patients (n = 480 myocardial segments), with known or suspected coronary artery disease (CAD). Dobutamine stress cardiovascular magnetic resonance (DS-CMR) and late gadolinium enhancement (LGE) were used to identify the viable non-ischemic, ischemic, and non-viable myocardial segments. Cine images at rest were used to calculate the segmental radial (Err), circumferential (Ecc), and longitudinal (Ell) strain parameters by manual contouring of endocardial and epicardial borders using Segment Software. Of the 480 myocardial segments and based on the DS-CMR and LGE results, 338 segments were defined as viable non-ischemic (remote), 101 segments were viable ischemic, and 41 segments were non-viable. Rest segmental Ecc, Err, and Ell values were significantly impaired in the non-viable (mean ± SD = - 3.94 ± 4.99%, 11.81 ± 12.55%, and - 7.50 ± 6.96%, respectively) compared to both viable groups, p < 0.001. Ecc and Err significantly differentiated between the non-ischemic and ischemic groups (mean ± SD = - 19.14 ± 7.20% vs - 13.18 ± 8.57% and 44.03 ± 19.56% vs 32.79 ± 17.91% respectively), p < 0.001. However, Ell showed no statistical significance between them (mean ± SD = - 16.44 ± 8.78% vs - 16.12 ± 10.00%, p = 0.945). CMR-FT can differentiate between viable and non-viable as well as ischemic and non-ischemic myocardial segments. So, such a noninvasive technique has a promising additional objective diagnostic role in conjunction with CMR in ischemia and viability assessment or even may replace stress and LGE studies in the future.

A woman in her 60s had 4 months of malaise, fatigue, dyspnoea, night sweats and grade 3 clubbing. She had a pansystolic murmur and signs of congestive heart failure. Multimodal imaging with a transthoracic echocardiogram, transoesophageal echocardiogram and CT was carried out to diagnose and reconstruct the mass for surgical planning. A 2×2.8 cm circular dense mass was found in the left atrium with vegetations on the mitral valve. Positron emission tomography and cardiac MRI confirmed the mass’s hypermetabolic activity and malignant features. Mitral valve replacement and surgical resection were performed. She was diagnosed with grade 3 undifferentiated cardiac sarcoma and referred to the sarcoma multidisciplinary team for further management given sarcoma’s rarity and complexity. The poor prognosis of sarcoma was evident as her symptoms recurred 2 months postoperatively.

Aim Enhanced recovery after surgery (ERAS) is not a fixed protocol; it is a new way of working. A questionnaire was done to measure the extent of doctor knowledge about ERAS protocols in mitral valve surgeries. The study aimed to assess the knowledge of doctors of ERAS guidelines in cardiac surgeries using the questionnaire grading system. Settings and design This cross-sectional study was carried out at the Cairo University Hospitals and the National Heart Institute, Egypt. Patients and methods A questionnaire was sent online to a random sample of anesthesiologists, cardiothoracic surgeons, and intensive care physicians. The random sample was taken using a random list. The questionnaire consists of a number of questions that the doctor has to answer in a set format. Results The most of answers were positive for the correct answer (protocol) and showed clearly that the doctor in the three different specialties knows about ERAS protocol in cardiac surgeries (mitral valve surgeries). Conclusions The ERAS protocols have been associated with a reduction in overall complications and length of stay of up to 50% compared with conventional perioperative patient management. This thesis clarifies that the three different groups of doctors have good knowledge of ERAS protocols, but the protocols have not been applied.

Aim Novel chest wall blocks were developed as the erector spinae plane block (ESPB) and retrolaminar block (RLB) to overcome postthoracotomy pain. The current study aimed to assess the safety and efficacy of combined RLB and ESPB versus ESPB alone for pain management following thoracotomy. Settings and design This randomized, double-blinded, parallel-group clinical trial was conducted at the university hospital. Patients and methods A total of 32 patients were enrolled in this study and were randomly assigned into two groups (16 patients each). The intervention group (ESPB/RLB) received preoperative ESPB using 10 ml of bupivacaine 0.25% plus RLB using 10 ml of bupivacaine 0.25% on the operated side, while the control group received preoperative ESPB only using 20 ml of bupivacaine 0.25% on the same side of the operation. Results The two groups showed no significant difference regarding pain, opioid consumption, hemodynamics, or time to first analgesic request. Conclusions The combination of ESPB and RLB did not demonstrate a superior analgesic effect for postthoracotomy pain compared with ESPB alone. However, it did result in a slightly lower incidence of postoperative nausea and vomiting, and hypotension.

The purpose of this study is to determine if real time ultrasound guidance improves the success rate of axillary brachial plexus blockade. Patients undergoing elective hand surgery were randomly assigned to one of three groups. Axillary blocks were performed using three motor response endpoints in the nerve stimulator (NS) Group, real-time ultrasound guidance in the ultrasound (US) Group and combined ultrasound and nerve stimulation in the USNS Group. Following administration of a standardized solution containing 2% lidocaine with 1:200,000 epinephrine and 0.5% bupivacaine (total 42 mL), sensory and motor functions were assessed by a blinded observer every five minutes for 30 min. A successful block was defined as complete sensory loss in the median, radial and ulnar nerve distribution by 30 min. The need for local and general anesthesia supplementation and post-block adverse events were documented. One hundred and eighty-eight patients completed the study. Block success rate was higher in Groups US and USNS (82.8% and 80.7%) than Group NS (62.9%) (P = 0.01 and 0.03 respectively). Fewer patients in Groups US and USNS required supplemental nerve blocks and/or general anesthesia. Postoperatively, axillary bruising and pain were reported more frequently in Group NS. This study demonstrates that ultrasound guidance, with or without concomitant nerve stimulation, significantly improves the success rate of axillary brachial plexus block.

Let \\(M\\) be a locally rotationally symmetric spacetime with at least one of the rotation or spatial twist being non-zero. It is proved that \\(M\\) cannot admit a non-minimal marginally trapped tube of the form \\(\\chi=X(t)\\).