Ultrasound-Guided Cervical Cervicis Plane Block for Postoperative Pain Control in Cervical Spine Surgery: A Technical Note.

BACKGROUND: New peripheral nerve blocks targeting the dorsal rami are possible for postoperative analgesia in patients undergoing posterior cervical spine surgeries. A cervical cervicis plane (CCeP) block can be performed under ultrasound guidance. We provide a description of this nerve block and ultrasound imaging with relevant sonographic structures. METHODS: Sonographic imaging from 2 spine surgeries showed CCeP blocks at the upper and lower cervical levels. RESULTS: A CCeP block targets the fascial plane between the semispinalis cervicis muscle and the semispinalis capitis muscle because the CCeP is a continuous plane from occiput to C7, which contains the dorsal rami of the cervical spinal nerves. The deep cervical artery can always be identified under ultrasound in this plane. CONCLUSIONS: The CCeP block is an easy nerve block to perform under ultrasound guidance to block the dorsal rami of the cervical nerves. It can provide effective analgesic effects for patients undergoing upper and lower posterior cervical spine surgery without compromising neurophysiology monitoring.

Traditional approach versus Stewart approach for acid-base disorders: Inconsistent evidence.

PURPOSE: The traditional approach and the Stewart approach have been developed for evaluating acid-base phenomena. While some experts have suggested that the two approaches are essentially identical, clinical researches have still been conducted on the superiority of one approach over the other one. In this review, we summarize the concepts of each approach and investigate the reasons of the discrepancy, based on current evidence from the literature search. METHODS: In the literature search, we completed a database search and reviewed articles comparing the Stewart approach with the traditional, bicarbonate-centered approach to November 2016. RESULTS: Our literature review included 17 relevant articles, 5 of which compared their diagnostic abilities, 9 articles compared their prognostic performances, and 3 articles compared both diagnostic abilities and prognostic performances. These articles show a discrepancy over the abilities to detect acid-base disturbances and to predict patients' outcomes. There are many limitations that could yield this discrepancy, including differences in calculation of the variables, technological differences or errors in measuring variables, incongruences of reference value, normal range of the variables, differences in studied populations, and confounders of prognostic strength such as lactate. CONCLUSION: In conclusion, despite the proposed equivalence between the traditional approach and the Stewart approach, our literature search shows inconsistent results on the comparison between the two approaches for diagnostic and prognostic performance. We found crucial limitations in those studies, which could lead to the reasons of the discrepancy.

A Comparison of Retrobulbar Versus Topical Anesthesia in Trabeculectomy and Aqueous Shunt Surgery.

PURPOSE: The purpose of this study was to compare the required supplemental anesthesia and postoperative patient pain score in individuals undergoing glaucoma surgery under topical anesthesia (TA) versus retrobulbar anesthesia (RB). MATERIALS AND METHODS: A retrospective, interventional, comparative cohort study of 261 eyes of 225 patients undergoing glaucoma and combined glaucoma with cataract surgery were included in the study. The main outcome measures were the amount of supplemental, systemic intraoperative anesthesia used and the postoperative pain scale between patients undergoing TA versus RB anesthesia. A secondary analysis was performed between combined glaucoma and cataract surgery versus glaucoma surgery alone. RESULTS: About 6.2% patients complained of pain after glaucoma surgery (8.1% among TA group and 3.1% among RB group; P=0.049). Overall, pain tended to be mild with a mean score of 0.32 of 10 for TA and 0.08 of 10 for RB (P=0.027). The amount of IV anesthetics used intraoperatively was lower in the RB anesthesia compared with the TA group (midazolam, P=0.042; fentanyl, P<0.001; propofol, P<0.001). In addition, patients undergoing RB anesthesia were less likely to use postoperative pain medication (P<0.001). There was no difference in pain score (P=0.707) or in the amount of IV anesthetics (all P>0.350) between eyes undergoing combined versus glaucoma surgery alone. CONCLUSIONS: Although supplemental anesthesia and pain scores were statistically increased in the topical group, the prevalence and the severity of pain was low. Therefore, TA is feasible and a reasonable option for glaucoma surgery. Furthermore, this conclusion applies when glaucoma surgery is performed alone or in combination with the other eye surgery.

Perioperative Management of Subarachnoid Hemorrhage in a Patient with Alagille Syndrome and Unrepaired Tetralogy of Fallot: Case Report.

Alagille syndrome (ALGS) is a genetic disorder associated with multisystem dysfunction involving the hepatic, cardiovascular, and neurologic systems. Tetralogy of Fallot (TOF), a congenital cardiac anomaly, is commonly found in these patients. Patients with ALGS may also have an increased risk of cerebrovascular abnormalities and bleeding. Ruptured cerebral aneurysm and subarachnoid hemorrhage (SAH) may be developed, increasing the incidence of morbidity and mortality. Advances in neuroimaging and neurosurgery have allowed early identification and treatment of such vascular abnormalities, improving patients' outcomes and reducing life-threatening complications such as intracranial bleeding. Authors describe the perioperative management of a patient with ALGS and TOF who was admitted to the emergency department due a ruptured intracranial aneurysm with concomitant SAH. Surgical treatment included diagnostic cerebral arteriography with coil embolization of a left posterior communicating artery aneurysm, and placement of right external ventricular drain (EVD). The combination of neuroprotective anesthetic techniques, fast emergence from anesthesia, and maintenance of intraoperative hemodynamic stability led to a successful perioperative management. A multidisciplinary approach in specialized centers is essential for the treatment of patients with SAH, especially in patients with ALGS and complex congenital heart disease such as TOF.

Perioperative Management of Dual-Antiplatelet Therapy in Patients With New-Generation Drug-Eluting Metallic Stents and Bioresorbable Vascular Scaffolds Undergoing Elective Noncardiac Surgery.

Dual-antiplatelet therapy (DAPT) is considered mandatory after new-generation drug-eluting coronary stent implantation to reduce ischemic complications such as stent thrombosis, but the need for DAPT makes the timing of elective surgery difficult. Interrupting DAPT places patients at risk for stent thrombosis, and surgery in the setting of DAPT may lead to bleeding. The 2016 American College of Cardiology/American Heart Association guideline recommends delaying elective noncardiac surgery for a minimum 6-month period to reduce ischemic risks after the implantation of a second-generation metallic drug-eluting stent (DES). However, the guideline fails to appropriately stratify surgical patients based on the indication for second-generation metallic DES implantation and other patient characteristics. The Absorb bioresorbable vascular scaffold (Abbott Vascular, Abbott Park, IL), which has a higher propensity for stent thrombosis compared with second-generation metallic DES, also produces DAPT management challenges in patients presenting for elective noncardiac surgery. Due to the novelty of bioresorbable vascular scaffold therapy, there are no guidelines available for the management of patients undergoing elective noncardiac surgery. This review addresses DAPT management in patients undergoing noncardiac surgery less than 12 months after new-generation metallic DES or bioresorbable vascular scaffold implantation and provides further guidance for anesthesiologists who encounter these challenging cases.

Incidental Finding of an Aorto-Right Atrial Fistula in a Patient Undergoing Repair of a Sinus of Valsalva Aneurysm.

A sinus of Valsalva aneurysm is a rare malformation of the aortic root that can fistulize to another cardiac structure such as the right atrium. Although transthoracic echocardiography and computed tomography angiography have demonstrated utility for the diagnosis of a sinus of Valsalva-to-right atrial fistula, there are few cases where a misdiagnosis may occur. Intraoperative transesophageal echocardiography may be an essential imaging tool for the diagnosis and management of incidental findings such as a sinus of Valsalva-to-right atrial fistula during cardiac surgery and should be used routinely.

Advanced Analgesic Drug Delivery and Nanobiotechnology.

Transdermal administration of analgesic medications offers several benefits over alternative routes of administration, including a decreased systemic drug load with fewer side effects, and avoidance of drug degradation by the gastrointestinal tract. Transdermal administration also offers a convenient mode of drug administration over an extended period of time, particularly desirable in pain medicine. A transdermal administration route may also offer increased safety for drugs with a narrow therapeutic window. The primary barrier to transdermal drug absorption is the skin itself. Transdermal nanotechnology offers a novel method of achieving enhanced dermal penetration with an extended delivery profile for analgesic drugs, due to their small size and relatively large surface area. Several materials have been used to enhance drug duration and transdermal penetration. The application of nanotechnology in transdermal delivery of analgesics has raised new questions regarding safety and ethical issues. The small molecular size of nanoparticles enables drug delivery to previously inaccessible body sites. To ensure safety, the interaction of nanoparticles with the human body requires further investigation on an individual drug basis, since different formulations have unique properties and side effects.

A Brief Review of Non-invasive Monitoring of Respiratory Condition for Extubated Patients with or at Risk for Obstructive Sleep Apnea after Surgery.

Obstructive sleep apnea (OSA) is one of the important risk factors contributing to postoperative airway complications. OSA alters the respiratory physiology and increases the sensitivity of muscle tone of the upper airway after surgery to residual anesthetic medication. In addition, the prevalence of OSA was reported to be much higher among surgical patients than the general population. Therefore, appropriate monitoring to detect early respiratory impairment in postoperative extubated patients with possible OSA is challenging. Based on the comprehensive clinical observation, several equipment have been used for monitoring the respiratory conditions of OSA patients after surgery, including the continuous pulse oximetry, capnography, photoplethysmography (PPG), and respiratory volume monitor (RVM). To date, there has been no consensus on the most suitable device as a recommended standard of care. In this review, we describe the advantages and disadvantages of some possible monitoring strategies under certain clinical conditions. According to the literature, the continuous pulse oximetry, with its high sensitivity, is still the most widely used device. It is also cost-effective and convenient to use but has low specificity and does not reflect ventilation. Capnography is the most widely used device for detection of hypoventilation, but it may not provide reliable data for extubated patients. Even normal capnography cannot exclude the existence of hypoxia. PPG shows the state of both ventilation and oxygenation, but its sensitivity needs further improvement. RVM provides real-time detection of hypoventilation, quantitative precise demonstration of respiratory rate, tidal volume, and MV for extubated patients, but no reflection of oxygenation. Altogether, the sole use of any of these devices is not ideal for monitoring of extubated patients with or at risk for OSA after surgery. However, we expect that the combined use of continuous pulse oximetry and RVM may be promising for these patients due to their complementary function, which need further study.

Preventing Ventilator-Associated Lung Injury: A Perioperative Perspective.

INTRODUCTION: Research into the prevention of ventilator-associated lung injury (VALI) in patients with acute respiratory distress syndrome (ARDS) in the intensive care unit (ICU) has resulted in the development of a number of lung protective strategies, which have become commonplace in the treatment of critically ill patients. An increasing number of studies have applied lung protective ventilation in the operating room to otherwise healthy individuals. We review the history of lung protective strategies in patients with acute respiratory failure and explore their use in patients undergoing mechanical ventilation during general anesthesia. We aim to provide context for a discussion of the benefits and drawbacks of lung protective ventilation, as well as to inform future areas of research. METHODS: We completed a database search and reviewed articles investigating lung protective ventilation in both the ICU and in patients receiving general anesthesia through May 2015. RESULTS: Lung protective ventilation was associated with improved outcomes in patients with acute respiratory failure in the ICU. Clinical evidence is less clear regarding lung protective ventilation for patients undergoing surgery. CONCLUSION: Lung protective ventilation strategies, including low tidal volume ventilation and moderate positive end-expiratory pressure, are well established therapies to minimize lung injury in critically ill patients with and without lung disease, and may provide benefit to patients undergoing general anesthesia.

Mitral Valve Stenosis after Open Repair Surgery for Non-rheumatic Mitral Valve Regurgitation: A Review.

Mitral stenosis (MS) after mitral valve (MV) repair is a slowly progressive condition, usually detected many years after the index MV surgery. It is defined as a mean transmitral pressure gradient (TMPG) >5 mmHg or a mitral valve area (MVA) <1.5 cm(2). Pannus formation around the mitral annulus or extending to the mitral leaflets is suggested as the main mechanism for developing delayed MS after MV repair. On the other hand, early stenosis is thought to be a direct result of an undersized annuloplasty ring. Furthermore, in MS following ischemic mitral regurgitation (MR) repair, subvalvular tethering is the hypothesized pathophysiology. MS after MV repair has an incidence of 9-54%. Several factors have been associated with a higher risk for developing MS after MV repair, including the use of flexible Duran annuloplasty rings versus rigid Carpentier-Edwards rings, complete annuloplasty rings versus partial bands, small versus large anterior leaflet opening angle, and anterior leaflet tip opening length. Intraoperative echocardiography can measure the anterior leaflet opening angle, the anterior leaflet tip opening dimension, the MVA and the mean TMPG, and may help identify patients at risk for developing MS after MV repair.