Temporal changes and predictors of perioperative blood transfusion in elective spine surgery: a retrospective analysis of a large surgical database.

BACKGROUND: Allogeneic blood transfusion used to be common in spine surgery. Patient blood management has been widely adopted, and it is important to reassess transfusion predictors in contemporary practice. METHODS: A retrospective study of inpatient spine surgery was performed using National Surgical Quality Improvement Program (NSQIP) data from 2011 to 2019. The primary outcome was perioperative transfusion within 72 h of surgery. Multivariable logistic regression and recursive partitioning were used to assess up to 15 variables including patient and surgical data, surgical specialty (orthopaedic surgery vs neurosurgery), and year of surgery. RESULTS: The study population included 251 971 US surgical patients; 6.9% of these patients received perioperative blood transfusion. Perioperative transfusions declined over time with the steepest decline from 2011 to 2015. The greatest reduction was seen among orthopaedic cases where the transfusion rate declined from 16.0% to 8.7% between 2011 and 2015. Eight variables were predictive factors in a reduced model: operative time, preoperative haemoglobin, vertebral level, number of vertebral levels, older age, surgeon specialty, arthrodesis, and year of surgery (area under the curve [AUC]=0.880; 95% confidence interval [CI], 0.878-0.883). Overall, longer operative time (>144 min) and greater numbers of vertebral levels had greater associations with transfusion than surgical specialty after adjustments. Prevalence of anaemia (15%) has not substantially declined. CONCLUSIONS: Perioperative blood transfusion rate in spine surgery has declined over the past decade. The extent and duration of surgery and preoperative haemoglobin level remain important factors associated with increased odds for perioperative blood transfusion.

Epidural anesthesia needle guidance by forward-view endoscopic optical coherence tomography and deep learning.

Epidural anesthesia requires injection of anesthetic into the epidural space in the spine. Accurate placement of the epidural needle is a major challenge. To address this, we developed a forward-view endoscopic optical coherence tomography (OCT) system for real-time imaging of the tissue in front of the needle tip during the puncture. We tested this OCT system in porcine backbones and developed a set of deep learning models to automatically process the imaging data for needle localization. A series of binary classification models were developed to recognize the five layers of the backbone, including fat, interspinous ligament, ligamentum flavum, epidural space, and spinal cord. The classification models provided an average classification accuracy of 96.65%. During puncture, it is important to maintain a safe distance between the needle tip and the dura mater. Regression models were developed to estimate that distance based on the OCT imaging data. Based on the Inception architecture, our models achieved a mean absolute percentage error of 3.05% ± 0.55%. Overall, our results validated the technical feasibility of using this novel imaging strategy to automatically recognize different tissue structures and measure the distances ahead of the needle tip during the epidural needle placement.

[Neuraxial analgesia in a parturient with the VACTERL association undergoing labor and vaginal delivery]. / Analgesia neuraxial em uma parturiente com síndrome de Vacterl em trabalho de parto normal.

INTRODUCTION: The term VACTERL is an acronym for an association of congenital malformations: including vertebral, anal, cardiac, tracheo-esophageal, renal and limb anomalies. VACTERL anomalies pose a formidable challenge to anesthesiologists. We describe the anesthetic management of a parturient with VACTERL association, who underwent neuraxial analgesia for labor and vaginal delivery. CASE REPORT: A 23 year old primigravida at 39 weeks gestation presented in labor at 4cm cervical dilatation, completely effaced, requesting labor analgesia. Past medical history included VACTERL association with an imperforate anus and a partial endocardial cushion defect, both repaired in early childhood. She also had significant dorso-lumbar scoliosis with an extra lumbar vertebra. An MRI performed at 14 years age revealed the above findings with no spinal cord abnormalities. With a normal neurologic exam, a combined spinal epidural technique was performed. Despite significant scoliosis, the epidural space was identified at approximately the L3-L4 interspace at a depth of 5cm. Spinal Fentanyl 25mcg was administered followed by continuous patient-controlled epidural analgesia. The patient experienced excellent pain relief throughout her labor, and had an uneventful vaginal delivery 5h after epidural placement. DISCUSSION: The rarity of VACTERL association in the obstetric population with its extensive anomalies mandates a multidisciplinary approach in the prenatal period as it can pose major challenges to all health care providers, including airway, ventilatory, cardiac and neuraxial problems. This is the first reported case of a successful and safe neuraxial technique in a laboring patient with the VACTERL association with albeit limited vertebral and spinal cord anomalies.

Prolonged respiratory depression after general anesthesia in an adult with congenital rubella syndrome.

Congenital rubella syndrome (CRS) is caused by rubella virus infection of the pregnant mother leading to teratogenic effects on the fetus. Although rare in the developed world, manifestations reach far into adulthood and underscore the importance of careful evaluation before surgery. We present a case of an adult with CRS in whom unexpected prolonged postoperative respiratory depression occurred. Perioperative workup of CRS and investigations pertaining to the patient's respiratory insufficiency are discussed.

Neuraxial analgesia in a parturient with the VACTERL association undergoing labor and vaginal delivery / Analgesia neuraxial em uma parturiente com síndrome de Vacterl em trabalho de parto normal

Abstract Introduction: The term VACTERL is an acronym for an association of congenital malformations: including vertebral, anal, cardiac, tracheo-esophageal, renal and limb anomalies. VACTERL anomalies pose a formidable challenge to anesthesiologists. We describe the anesthetic management of a parturient with VACTERL association, who underwent neuraxial analgesia for labor and vaginal delivery. Case report: A 23 year old primigravida at 39 weeks gestation presented in labor at 4 cm cervical dilatation, completely effaced, requesting labor analgesia. Past medical history included VACTERL association with an imperforate anus and a partial endocardial cushion defect, both repaired in early childhood. She also had significant dorso-lumbar scoliosis with an extra lumbar vertebra. An MRI performed at 14 years age revealed the above findings with no spinal cord abnormalities. With a normal neurologic exam, a combined spinal epidural technique was performed. Despite significant scoliosis, the epidural space was identified at approximately the L3-L4 interspace at a depth of 5 cm. Spinal Fentanyl 25 mcg was administered followed by continuous patient-controlled epidural analgesia. The patient experienced excellent pain relief throughout her labor, and had an uneventful vaginal delivery 5 h after epidural placement. Discussion: The rarity of VACTERL association in the obstetric population with its extensive anomalies mandates a multidisciplinary approach in the prenatal period as it can pose major challenges to all health care providers, including airway, ventilatory, cardiac and neuraxial problems. This is the first reported case of a successful and safe neuraxial technique in a laboring patient with the VACTERL association with albeit limited vertebral and spinal cord anomalies.

Resumo Introdução: O termo Vacterl é um acrônimo para uma associação de malformacões congênitas que inclui anomalias vertebral, anal, cardíaca, traqueal, esofágica, renal e dos membros (Limbs em inglês). As anomalias Vacterl representam um enorme desafio para os anestesiologistas. Descrevemos o manejo anestésico de uma parturiente com síndrome de Vacterl submetida à analgesia neuraxial para parto normal. Relato de caso: Paciente primípara, 23 anos, 39 semanas de gestação, apresentava em trabalho de parto 4 cm de dilatação cervical, apagamento completo, exigiu analgesia de parto. A história médica incluía síndrome de Vacterl com ânus imperfurado e defeito parcial do coxim endocárdico, ambos corrigidos na primeira infância. A paciente também apresentava escoliose dorso-lombar acentuada com uma vértebra lombar adicional. Uma RM feita aos 14 anos revelou os achados mencionados acima sem anormalidades na medula espinhal. Com um exame neurológico normal, a técnica anestésica combinada raquiperidural (CRP) foi usada. Apesar de escoliose significativa, o espaço peridural foi identificado próximo ao interespaço L3-L4 a uma profundidade de 5 cm. Fentanyl (25 mcg) foi administrado por via espinhal, seguido de analgesia peridural contínua controlada pela paciente. A paciente sentiu grande alívio da dor durante todo o trabalho de parto; o parto vaginal ocorreu 5 horas após a anestesia CRP sem intercorrências. Discussão: A raridade da síndrome de Vacterl na população obstétrica com suas extensas anomalias exige uma abordagem multidisciplinar no pré-natal porque pode representar grandes desafios para todos os prestadores de cuidados de saúde, inclusive problemas respiratórios, de ventilação, cardíacos e do neuroeixo. Este é o primeiro caso relatado de uma técnica neuraxial bem-sucedida e segura em uma paciente em trabalho de parto com síndrome de Vacterl, embora com anomalias limitadas da coluna vertebral e medula espinhal.