Claudio Luciano Franck

Background Mechanical power (MP) integrates multiple ventilatory variables into a single measure of the energy delivered to the respiratory system and has been associated with ventilator-induced lung injury and adverse outcomes. However, it remains unclear whether ventilatory observations meeting conventional protective criteria also exhibit low MP and whether small ventilatory adjustments can meaningfully reduce MP in severely burned patients undergoing pressure-controlled ventilation (PCV). Methods This interventional repeated-measures study with randomized sequence of ventilatory adjustment protocols included adult burn patients receiving PCV in an intensive care unit. A total of 123 paired ventilatory observations were screened. Three reductive ventilatory strategies were assessed: reduction of inspiratory pressure variation by 2 cmH2O (ΔPinsp), reduction of respiratory rate by 2 breaths/min (RR), and combined reductions of 1 cmH2O and 1 breath/min (RR–ΔPinsp). Thirty-nine ventilatory observations meeting predefined protective tidal-volume and pressure criteria constituted the analytical sample. MP was calculated using the simplified Becher equation. Clinical, arterial blood gases, and ventilatory effects were evaluated at baseline and one hour after the interventions, as well as migration between MP categories (<1 8 and ≥ 18 J/min). Results Oxygenation remained stable, with no significant changes in PaO2, SpO2, or PaO2/FiO2. PaCO2 increased modestly and arterial pH decreased slightly, but both remained within physiological limits. No desaturation, clinically relevant acidosis, hemodynamic instability, or ventilatory asynchrony was observed. Among the 39 ventilatory observations, 17 (43.6%) had MP ≥ 18 J/min at baseline. MP decreased significantly from 17.39 to 15.02 J/min overall (P < 0.001). The greatest reduction was observed in the ΔPinsp group (3.00 J/min), followed by RR–ΔPinsp (2.34 J/min) and RR (1.78 J/min), with significant differences among strategies. Ventilatory observations with MP <18 J/min increased from 22/39 (56.4%) to 34/39 (87.2%), whereas those with MP ≥ 18 J/min decreased from 17/39 (43.6%) to 5/39 (12.8%) (P < 0.001). Conclusions A substantial proportion of ventilatory observations meeting conventional protective criteria still exhibited elevated MP. Small ventilatory adjustments during protective PCV were associated with significant reductions in calculated MP and migration toward values below 18 J/min without compromising short-term arterial blood gases or clinical stability. Reduction in inspiratory pressure variation produced the greatest effect on MP. Keywords: Mechanical Power, Burns; Mechanical Ventilation; Pressure-Controlled Ventilation; Ventilator-Induced Lung Injury.

Introduction: Central nervous system solitary fibrous tumors (CNS-SFTs), previously classified as hemangiopericytomas, are rare and highly vascular mesenchymal neoplasms characterized by an aggressive biological behavior, high recurrence rates, and propensity for venous sinus invasion. Gross-total en bloc resection remains the cornerstone of treatment whenever technically feasible. We present the microsurgical management of a recurrent CNS solitary fibrous tumor invading the transverse sinus. Case Report: A 30-year-old man previously underwent microsurgical resection of a central nervous system solitary fibrous tumor two years earlier. He presented with recurrent headaches associated with visual photopsias. Magnetic resonance imaging demonstrated tumor recurrence centered at the left occipital region with extensive invasion of the left transverse sinus. Preoperative digital subtraction angiography confirmed complete occlusion of the left transverse sinus, allowing safe planning for sinus sacrifice during tumor resection. Microsurgical treatment was performed through a combined left occipital supratentorial and infratentorial craniotomy. To maximize exposure of the transverse-sigmoid junction, a retrosigmoid mastoidectomy was performed, permitting complete skeletonization of the transverse and sigmoid sinuses and facilitating vascular control. Following extradural exposure, the proximal transverse sinus was ligated near the torcular Herophili under direct microscopic visualization after confirming intraluminal tumor extension. Distal ligation was subsequently completed, and the tumor was removed en bloc together with the invaded segment of the transverse sinus, achieving gross-total resection while preserving the surrounding neurovascular structures. Results: The immediate postoperative neurological examination demonstrated no new neurological deficits. During the postoperative period, the patient developed communicating hydrocephalus, cerebrospinal fluid leakage, and bacterial meningitis. These complications were successfully managed with direct surgical repair of the cerebrospinal fluid fistula, implantation of a programmable ventriculoperitoneal shunt, and targeted intravenous antibiotic therapy. The patient recovered without permanent neurological sequelae. Postoperative magnetic resonance imaging confirmed gross-total tumor resection, and follow-up imaging demonstrated no evidence of residual disease. Conclusion: Complete microsurgical resection remains the treatment of choice for recurrent CNS solitary fibrous tumors involving the dural venous sinuses. When preoperative angiography confirms complete venous sinus occlusion, en bloc resection of the involved transverse sinus can be safely performed. A combined occipital supratentorial-infratentorial approach with adjunctive mastoidectomy provides excellent exposure of the transverse-sigmoid junction, facilitating vascular control and radical tumor removal while minimizing neurological morbidity.

Introduction: Endolymphatic sac tumors (ELSTs) are rare, locally aggressive papillary neoplasms arising from the endolymphatic sac and duct. Although histologically benign, they may behave aggressively due to progressive bone erosion and invasion of adjacent neurovascular structures. Patients commonly present with progressive hearing loss, tinnitus, vertigo, and vestibular dysfunction, significantly affecting quality of life. Complete microsurgical resection remains the treatment of choice for symptomatic tumors, providing excellent long-term control when total removal is achieved. We present the surgical management of an endolymphatic sac tumor through a transmastoid approach, emphasizing anatomical landmarks and microsurgical principles. Case Report: A 40-year-old man presented with progressive left-sided pulsatile tinnitus, hearing loss, episodic vertigo, and aural fullness, causing significant functional impairment. Computed tomography revealed irregular erosive destruction of the retrolabyrinthine temporal bone, a characteristic finding of ELST. Magnetic resonance imaging demonstrated an intensely enhancing lesion centered on the left endolymphatic sac, located along the posterior surface of the petrous bone and adjacent to the posterior semicircular canal and sigmoid sinus. Microsurgical resection was performed through a transmastoid approach. After complete mastoidectomy, the sigmoid sinus, posterior semicircular canal, and Trautmann’s triangle were widely exposed, providing access to the posterior petrous region. Careful drilling and anatomical identification of surrounding structures allowed controlled tumor exposure while preserving the labyrinth and neurovascular anatomy. The posterior fossa dura within Trautmann’s triangle was opened, enabling direct visualization and complete microsurgical resection under high magnification. Tumor dissection was performed with meticulous attention to its relationship with the sigmoid sinus, posterior semicircular canal, and facial nerve. Continuous unimodal intraoperative facial nerve monitoring was used throughout the procedure, allowing functional assessment and preservation of facial nerve integrity. Gross-total tumor removal was achieved without injury to surrounding neurovascular structures. The operative field was carefully inspected to confirm complete resection and adequate hemostasis. Results: The postoperative course was uneventful, with complete resolution of pulsatile tinnitus and preservation of facial nerve function. The patient remained neurologically intact during long-term follow-up. After 12 years of clinical and radiological surveillance, there was no evidence of tumor recurrence, and the patient remained asymptomatic with preserved neurological function. Conclusion: The transmastoid approach provides a direct and effective surgical corridor for selected endolymphatic sac tumors. Wide exposure of Trautmann’s triangle allows safe access to the posterior petrous region, facilitating complete microsurgical resection while minimizing morbidity. This case demonstrates that tailored skull base surgery can provide durable tumor control and excellent long-term functional outcomes when complete removal is anatomically feasible.

Introduction: Multiple head and neck paragangliomas are rare neuroendocrine tumors that present unique management challenges because of their multicentricity, close relationship with major neurovascular structures, and the need to preserve cranial nerve function. Careful staging and sequential surgical planning are essential to minimize neurological morbidity. We present the staged microsurgical management of synchronous bilateral carotid body tumors associated with a right jugular foramen paraganglioma. Case Report: A 46-year-old woman came with a firm, painless left-sided cervical mass and right-sided pulsatile tinnitus. Neurological examination demonstrated no cranial nerve deficits. Twenty-four-hour urinary vanillylmandelic acid (VMA) levels were within normal limits, excluding a functioning paraganglioma. Magnetic resonance imaging and computed tomography angiography demonstrated three synchronous paragangliomas: a right carotid body tumor (Shamblin type I), a right jugular foramen paraganglioma, and a left carotid body tumor (Shamblin type III) encasing the carotid bifurcation. Because the right jugular foramen lesion was responsible for the patient's pulsatile tinnitus and represented the most complex lesion, a staged surgical strategy was adopted. Seventy-two hours before surgery, the jugular foramen paraganglioma underwent selective endovascular embolization using calibrated microparticles, achieving significant devascularization. The first-stage procedure consisted of a modified Fisch type A infratemporal fossa approach, preserving the facial nerve in its anatomical position without anterior rerouting. Through the same cervical exposure, the right carotid body tumor was completely dissected from the carotid bifurcation and excised, followed by microsurgical resection of the jugular foramen paraganglioma. Careful microsurgical dissection allowed preservation of the lower cranial nerves, facial nerve, internal carotid artery, internal jugular vein, and surrounding neurovascular structures. Gross-total resection of both tumors was achieved. Results: The patient experienced complete resolution of pulsatile tinnitus and remained neurologically intact without new postoperative cranial nerve deficits. Six months later, the contralateral Shamblin type III carotid body tumor was resected through a standard transcervical approach. Because of its favorable vascular anatomy, preoperative embolization was not performed. Careful subadventitial microsurgical dissection allowed complete tumor removal while preserving the common, internal, and external carotid arteries, as well as the vagus and hypoglossal nerves. The postoperative course was uneventful, without vascular or neurological complications. Conclusion: Staged microsurgical treatment represents a safe and effective strategy for patients with multiple head and neck paragangliomas. Prioritizing the symptomatic and technically more complex lesion allows preservation of cranial nerve function while reducing overall surgical morbidity. A modified Fisch type A approach without facial nerve transposition provides excellent exposure for selected jugular foramen paragangliomas, and meticulous microsurgical technique permits safe resection of synchronous carotid body tumors with excellent functional outcomes.

Introduction: Multiple head and neck paragangliomas are rare neuroendocrine tumors that present unique management challenges because of their multicentricity, close relationship with major neurovascular structures, and the need to preserve cranial nerve function. Careful staging and sequential surgical planning are essential to minimize neurological morbidity. We present the staged microsurgical management of synchronous bilateral carotid body tumors associated with a right jugular foramen paraganglioma. Case Report: A 46-year-old woman came with a firm, painless left-sided cervical mass and right-sided pulsatile tinnitus. Neurological examination demonstrated no cranial nerve deficits. Twenty-four-hour urinary vanillylmandelic acid (VMA) levels were within normal limits, excluding a functioning paraganglioma. Magnetic resonance imaging and computed tomography angiography demonstrated three synchronous paragangliomas: a right carotid body tumor (Shamblin type I), a right jugular foramen paraganglioma, and a left carotid body tumor (Shamblin type III) encasing the carotid bifurcation. Because the right jugular foramen lesion was responsible for the patient's pulsatile tinnitus and represented the most complex lesion, a staged surgical strategy was adopted. Seventy-two hours before surgery, the jugular foramen paraganglioma underwent selective endovascular embolization using calibrated microparticles, achieving significant devascularization. The first-stage procedure consisted of a modified Fisch type A infratemporal fossa approach, preserving the facial nerve in its anatomical position without anterior rerouting. Through the same cervical exposure, the right carotid body tumor was completely dissected from the carotid bifurcation and excised, followed by microsurgical resection of the jugular foramen paraganglioma. Careful microsurgical dissection allowed preservation of the lower cranial nerves, facial nerve, internal carotid artery, internal jugular vein, and surrounding neurovascular structures. Gross-total resection of both tumors was achieved. Results: The patient experienced complete resolution of pulsatile tinnitus and remained neurologically intact without new postoperative cranial nerve deficits. Six months later, the contralateral Shamblin type III carotid body tumor was resected through a standard transcervical approach. Because of its favorable vascular anatomy, preoperative embolization was not performed. Careful subadventitial microsurgical dissection allowed complete tumor removal while preserving the common, internal, and external carotid arteries, as well as the vagus and hypoglossal nerves. The postoperative course was uneventful, without vascular or neurological complications. Conclusion: Staged microsurgical treatment represents a safe and effective strategy for patients with multiple head and neck paragangliomas. Prioritizing the symptomatic and technically more complex lesion allows preservation of cranial nerve function while reducing overall surgical morbidity. A modified Fisch type A approach without facial nerve transposition provides excellent exposure for selected jugular foramen paragangliomas, and meticulous microsurgical technique permits safe resection of synchronous carotid body tumors with excellent functional outcomes.

Introduction: Endolymphatic sac tumors (ELSTs) are rare, locally aggressive papillary neoplasms arising from the endolymphatic sac and duct. Although histologically benign, they may behave aggressively due to progressive bone erosion and invasion of adjacent neurovascular structures. Patients commonly present with progressive hearing loss, tinnitus, vertigo, and vestibular dysfunction, significantly affecting quality of life. Complete microsurgical resection remains the treatment of choice for symptomatic tumors, providing excellent long-term control when total removal is achieved. We present the surgical management of an endolymphatic sac tumor through a transmastoid approach, emphasizing anatomical landmarks and microsurgical principles. Case Report: A 40-year-old man presented with progressive left-sided pulsatile tinnitus, hearing loss, episodic vertigo, and aural fullness, causing significant functional impairment. Computed tomography revealed irregular erosive destruction of the retrolabyrinthine temporal bone, a characteristic finding of ELST. Magnetic resonance imaging demonstrated an intensely enhancing lesion centered on the left endolymphatic sac, located along the posterior surface of the petrous bone and adjacent to the posterior semicircular canal and sigmoid sinus. Microsurgical resection was performed through a transmastoid approach. After complete mastoidectomy, the sigmoid sinus, posterior semicircular canal, and Trautmann’s triangle were widely exposed, providing access to the posterior petrous region. Careful drilling and anatomical identification of surrounding structures allowed controlled tumor exposure while preserving the labyrinth and neurovascular anatomy. The posterior fossa dura within Trautmann’s triangle was opened, enabling direct visualization and complete microsurgical resection under high magnification. Tumor dissection was performed with meticulous attention to its relationship with the sigmoid sinus, posterior semicircular canal, and facial nerve. Continuous unimodal intraoperative facial nerve monitoring was used throughout the procedure, allowing functional assessment and preservation of facial nerve integrity. Gross-total tumor removal was achieved without injury to surrounding neurovascular structures. The operative field was carefully inspected to confirm complete resection and adequate hemostasis. Results: The postoperative course was uneventful, with complete resolution of pulsatile tinnitus and preservation of facial nerve function. The patient remained neurologically intact during long-term follow-up. After 12 years of clinical and radiological surveillance, there was no evidence of tumor recurrence, and the patient remained asymptomatic with preserved neurological function. Conclusion: The transmastoid approach provides a direct and effective surgical corridor for selected endolymphatic sac tumors. Wide exposure of Trautmann’s triangle allows safe access to the posterior petrous region, facilitating complete microsurgical resection while minimizing morbidity. This case demonstrates that tailored skull base surgery can provide durable tumor control and excellent long-term functional outcomes when complete removal is anatomically feasible.

Introduction: Central nervous system solitary fibrous tumors (CNS-SFTs), previously classified as hemangiopericytomas, are rare and highly vascular mesenchymal neoplasms characterized by an aggressive biological behavior, high recurrence rates, and propensity for venous sinus invasion. Gross-total en bloc resection remains the cornerstone of treatment whenever technically feasible. We present the microsurgical management of a recurrent CNS solitary fibrous tumor invading the transverse sinus. Case Report: A 30-year-old man previously underwent microsurgical resection of a central nervous system solitary fibrous tumor two years earlier. He presented with recurrent headaches associated with visual photopsias. Magnetic resonance imaging demonstrated tumor recurrence centered at the left occipital region with extensive invasion of the left transverse sinus. Preoperative digital subtraction angiography confirmed complete occlusion of the left transverse sinus, allowing safe planning for sinus sacrifice during tumor resection. Microsurgical treatment was performed through a combined left occipital supratentorial and infratentorial craniotomy. To maximize exposure of the transverse-sigmoid junction, a retrosigmoid mastoidectomy was performed, permitting complete skeletonization of the transverse and sigmoid sinuses and facilitating vascular control. Following extradural exposure, the proximal transverse sinus was ligated near the torcular Herophili under direct microscopic visualization after confirming intraluminal tumor extension. Distal ligation was subsequently completed, and the tumor was removed en bloc together with the invaded segment of the transverse sinus, achieving gross-total resection while preserving the surrounding neurovascular structures. Results: The immediate postoperative neurological examination demonstrated no new neurological deficits. During the postoperative period, the patient developed communicating hydrocephalus, cerebrospinal fluid leakage, and bacterial meningitis. These complications were successfully managed with direct surgical repair of the cerebrospinal fluid fistula, implantation of a programmable ventriculoperitoneal shunt, and targeted intravenous antibiotic therapy. The patient recovered without permanent neurological sequelae. Postoperative magnetic resonance imaging confirmed gross-total tumor resection, and follow-up imaging demonstrated no evidence of residual disease. Conclusion: Complete microsurgical resection remains the treatment of choice for recurrent CNS solitary fibrous tumors involving the dural venous sinuses. When preoperative angiography confirms complete venous sinus occlusion, en bloc resection of the involved transverse sinus can be safely performed. A combined occipital supratentorial-infratentorial approach with adjunctive mastoidectomy provides excellent exposure of the transverse-sigmoid junction, facilitating vascular control and radical tumor removal while minimizing neurological morbidity.

Introdução: O traumatismo cranioencefálico é um dos maiores problemas de saúde e socioeconômicos que impactam as sociedades ao redor do mundo. Objetivo: Revisar a literatura quanto a eficiência da hipotermia seletiva prolongada (por 12 h) associada à craniectomia descompressiva no tratamento do traumatismo cranioencefálico. Método: Revisão integrativa feita colhendo dados em plataformas virtuais. Inicialmente foi realizada busca por descritores DECs relacionados ao tema, utilizando os seguintes termos: “traumatismo cranioencefálico; hipotermia; hipotermia seletiva; craniotomia descompressiva” com busca AND ou OR, considerando o título e/ou resumo e os escolhidos foram lidos na íntegra. O material para leitura e análise foi selecionado das plataformas SciELO, Google Scholar, Pubmed e Scopus. Resultado: Considerando-se somente os que tinham maior relação ao tema incluíram-se 73 artigos. Conclusão: Os resultados obtidos pelos experimentos estimulam desenvolvimento de novos estudos durante tempo maior de exposição à hipotermia, por volta de 24 h, e com análises da ação da hipotermia seletiva em relação aos marcadores inflamatórios e quemoquinas. Essa proposta deve dar mais informações relevantes sobre os efetivos benefícios dessa terapêutica.