Progress and research status of ocular venous air embolism caused by vitrectomy / 国际眼科杂志(Guoji Yanke Zazhi)

Ocular venous air embolism(OVAE)is a rare and fatal complication in vitrectomy. Due to the proximity of the surgical site to the heart and its level above the heart, OVAE may be the most severe complication in the venous air embolism(VAE)caused by surgery. With the development of vitrectomy, perfusion cannulas in the suture-free state may slide outward, and the perfused gas can enter the suprachoroidal space, which results in tearing of the vortex veins. Choroidal vascular wounds resulting from trauma and endoresection of choroidal melanoma can expose directly in the perfused gas during vitreous cavity gas-liquid exchange. This makes it possible that the pressurized gas enters the circulatory system through the torn vortex veins or the anomalous choroidal venous openings, which leads to OVAE. Nowadays, the definition, pathogenesis, clinical presentation and prevention of OVAE are being refined. However, most vitreoretinal surgeons and anesthesiologists are still unaware of this iatrogenic complication. It will be helpful to detect this complication early and make emergency management in time by increasing the awareness of OVAE and develop effective prevention strategies. The prevention and control principles of OVAE can be continuously optimized by the combination of clinical and laboratory studies. It will be conducive to the establishment and improvement of emergency treatment and preventive measures of OVAE to fully understand the pathogenesis and clinical characteristics of OVAE, to pay attention to the characteristics of secondary lesions of OVAE, and to attach importance to multi-disciplinary cooperation.

Posición semisentada en neurocirugía. Nota técnica y presentación de casos ilustrativos / Semi-sitting position in neurosurgery. Technical note and illustrative case presentation

Introducción: En las últimas décadas el uso de la posición sentada ha disminuido en frecuencia a causa de 2 complicaciones mayores: el embolismo aéreo venoso y la hipotensión intraoperatoria. Sin embargo es innegable que la posición sentada ofrece una serie de ventajas al neurocirujano, el anestesiólogo y al electrofisiólogo. Materiales y métodos: Estudio retrospectivo de pacientes operados en dos instituciones de Tucumán, entre enero de 2015 y diciembre de 2019. Resultados: Se operaron un total de 119 pacientes en posición sentada por vía posterior. Conclusión: Se presentó la técnica de posición semisentada paso a paso y consejos específicos. Se ilustró la utilidad de la misma mediante la presentación de casos representativos

Introduction: In the last decades, the use of the sitting position has been abandoned due to 2 major complications: venous air embolism and intraoperative hypotension. However, it is undeniable that the sitting position offers a series of advantages to the neurosurgeon, the anesthesiologist and the electrophysiologist. Materials and methods: Retrospective study of patients operated at two institutions in Tucumán, between January 2015 and December 2019. Results: A total of 119 patients were operated in a sitting position and posterior approach. Conclusion: The sitting position technique was presented step by step in detail, with the key steps and a series of tricks. The usefulness of the position was illustrated by presenting representative cases

Complicaciones hemodinámicas en una faco-vitrectomía: sospecha de una embolia aérea / Hemodynamic complications in a phaco-vitrectomy: suspicion of an air embolism

La embolia aérea es una complicación quirúrgica potencialmente fatal, que debe manejarse rápida y precozmente, por lo que su reconocimiento temprano es esencial. Al tener una amplia gama de posibles manifestaciones clínicas, la sospecha diagnóstica en base al procedimiento quirúrgico es fundamental. Presentamos el caso de una paciente de 69 años sometida a una faco-vitrectomía con anestesia general que sufrió un colapso hemodinámico brusco durante la fase de intercambio aire/fluido.(AU)

: Venous air embolism is a potentially fatal surgical complication which must be managed quickly, so early recognition is essential. Having a wide range of possible clinical manifestations, it requires a high index of suspicion based on the surgical procedure.We report a case of a 69-year-old woman undergoing general anesthesia for phaco-vitrectomy who suffered a sudden hemodynamic collapse during the air fluid exchange phase.(AU)

Presencia de gas en estructuras vasculares venosas encefálicas como hallazgo incidental en tomografía computada de encéfalo en ausencia de trauma / Presence of gas in encephalic vascular venous structures as an incidental finding in brain computed tomography in the absence of trauma

The presence of gas in the cerebral vascular venous structures is a finding that we infrequently see in our specialty. On many occasions we cannot pinpoint the cause, alarming the clinician, suggesting unnecessary exams, hospitalizations and controls. We performed a review of the literature and a retrospective study with the cases that we have reported in computed tomography of the brain in our radiology service, from January 2010 to July 2017.

La presencia de gas en las estructuras vasculares venosas cerebrales es un hallazgo que vemos infrecuentemente en nuestra especialidad. En muchas ocasiones no podemos precisar la causa, alarmando al clínico, sugiriendo exámenes, hospitalizaciones y controles innecesarios. Realizamos una revisión de la literatura y un trabajo retrospectivo con los casos que hemos reportado en tomografías computadas de encéfalo en nuestro servicio de radiología, desde enero del 2010 a julio del 2017.

Simple handling of venous air embolism during abdominal myomectomy / Manejo simples de embolia gasosa durante miomectomia abdominal

Abstract We report a case of venous air embolism during abdominal myomectomy. Although true incidence of venous air embolism is not known, in literature most of reported cases are belongs to sitting position craniotomies. Many of those are subclinical, and diagnostic methods have varying degrees of sensitivity and specificity. At time of suspicion, prevention of any subsequent air emboli is the cornerstone of treatment.

Resumo Relatamos um caso de embolia gasosa durante miomectomia abdominal. Embora a incidência exata de embolia gasosa não seja conhecida, a maioria dos casos relatados na literatura se refere à posição sentada em craniotomias. Muitos casos são subclínicos e os métodos diagnósticos têm diferentes graus de sensibilidade e especificidade. No momento da suspeita, a prevenção de qualquer êmbolo de ar subsequente é a chave fundamental do tratamento.

Clinical features of venous air embolism and its correlation with cough in deep brain stimulation surgery / 实用医学杂志

Objective To investigate the clinical features of VAE and to assess the predictive value of VAE cough. Methods We retrospectively reviewed the medical records of 461 consecutive patients who underwent DBS surgery at Beijing Tiantan Hospital. Patients with VAE manifestation were enrolled in this study. The clinical features, operative courses, post-operative conditions and treatment of these patients were analyzed. The correlation between intraoperative tremor intensity , cough duration and prognosis was also investigated. Results Among 461 patients,10 (2.2%) were found with evidence of VAE, including cough, dyspnea, decreased O2 saturation (SO2). Statistical analyses revealed that severe cough was associated with greater age , a longer coughing time, more intensive tremor, greater influence, and a longer length of stay (P < 0.05, rspectively). Conclusions Early recognition and prompt management of VAE are essential to prevent unfavorable consequences. Cough intensity might be a useful tool for evaluating VAE and its prognosis , which is helpful for neurosurgeons to decide on the subsequent maneuvers.

Venous Air Embolism during Elective Craniotomy for Parasagittal Meningioma

We report a case of a 59 year old man who developed venous air embolism (VAE) during an elective craniotomy for parasagittal meningioma resection. The surgery was done in the supine position with slightly elevated head position. VAE was provisionally diagnosed by sudden decreased in the end tidal carbon dioxide pressure from 34 to 18 mmHg, followed by marked hypotension and atrial fibrillation. Prompt central venous blood aspiration, aggressive resuscitation and inotropic support managed to stabilize the patient. Post operatively, he was admitted in neuro intensive care unit and made a good recovery without serious complications.

Incidence of Venous Air Embolism during Myomectomy: The Effect of Patient Position

PURPOSE: Venous air embolism (VAE) is characterized by the entrainment of air or exogenous gases from broken venous vasculature into the central venous system. No study exists regarding the effect of patient positioning on the incidence of VAE during abdominal myomectomy. The purpose of this study was to assess the incidence and grade of VAE during abdominal myomectomy in the supine position in comparison to those in the head-up tilt position using transesophageal echocardiography. MATERIALS AND METHODS: In this study, 84 female patients of American Society of Anesthesiologist physical status I or II who were scheduled for myomectomy under general anesthesia were included. Patients were randomly divided into two groups: supine group and head-up tilt group. Transesophageal echocardiography images were videotaped throughout the surgery. The tapes were then reviewed for VAE grading. RESULTS: In the supine group, 10% of the patients showed no VAE. Moreover, 10% of the patients were classified as grade I VAE, while 50% were categorized as grade II, 22.5% as grade III, and 7.5% as grade IV. In the head-up tilt group, no VAE was detected in 43.2% of the patients. In addition, 18.2% of the patients were classified as grade I VAE, 31.8% as grade II, and 6.8% as grade III; no patients showed grade IV. VAE grade in the head-up tilt group was significantly lower than that in the supine group (p<0.001). CONCLUSION: The incidence and grade of VAE in the head-up tilt group were significantly lower than those in the supine group during abdominal myomectomy.

Venous air embolism during hepatic resection in a patient with liver cirrhosis: A case report

Venous air embolism (VAE) is a potentially fatal complication in patients with chronic liver disease during liver surgery, although VAE is unlikely to occur during laparotomy in a supine position. We report a case presenting unexpected cardiovascular collapse due to venous air embolism in a patient with liver cirrhosis during hepatic resection.

Prolonged paradoxical air embolism during intraoperative intestinal endoscopy confirmed by transesophageal echocardiography: A case report- / 대한마취과학회지

Venous air embolism (VAE) during intestinal endoscopy is a rare complication. We report a case of cardiovascular collapse due to VAE confirmed by transesophageal echocardiography (TEE) during intraoperative intestinal endoscopy. TEE detected air bubbles in the left ventricle up to 1 hour after the event. When a patient deteriorates during endoscopic procedures, VAE and possible paradoxical air embolism (PAE) should be suspected. This case demonstrates that TEE can play an important role in diagnosing and managing an air embolism in anesthetized patients. In addition, this case demonstrates that PAEs may occur longer than expected after recovery from VAE-induced cardiovascular collapse.

Venous Air Embolism during Surgery, Especially Cesarean Delivery

Venous air embolism (VAE) is the entrapment of air or medical gases into the venous system causing symptoms and signs of pulmonary vessel obstruction. The incidence of VAE during cesarean delivery ranges from 10 to 97% depending on surgical position or diagnostic tools, with a potential for life-threatening events. We reviewed extensive literatures regarding VAE in detail and herein described VAE during surgery including cesarean delivery from background and history to treatment and prevention. It is intended that present work will improve the understanding of VAE during surgery.

Acoustic neuroma (vestibular schwannoma): surgical results on 240 patients operated on dorsal decubitus position

OBJECTIVE: To evaluate the result of the surgical treatment of vestibular schwannoma (VS) operated in dorsal decubitus (mastoid position). METHOD: 240 patients with a VS underwent a retrosigmoid craniotomy for tumor resection in dorsal decubitus (mastoid position). The function of 7th and 8th cranial nerves was monitored during surgery and the opened internal auditory canal (IAC) was reconstructed using a vascularized dura flap, muscle and fibrin glue. RESULTS: Complete tumor removal was achieved in 99 percent of the cases, with a mortality of 1.6 percent. The facial nerve function was preserved in 85 percent of cases and hearing in 40 percent of the patients (with preoperative hearing) with tumors of up 1.5 cm in diameter. The incidence of cerebrospinal fluid leak was 5.8 percent and meningitis 2.9 percent. Venous air embolism was registered in 3 percent of cases; it was not associated to mortality. CONCLUSION: Surgical removal of VS in dorsal position has several advantages; the morbidity and mortality are very low.

OBJETIVO: Avaliar o resultado do tratamento cirúrgico de pacientes portadores de schwannoma do vestibular (SV) operados em decúbito dorsal (posição de mastóide). MÉTODO: 240 pacientes foram submetidos a craniotomia retrosigmóide na posição de mastóide. A função do VII e VIII nervos cranianos foi monitorizada durante a cirurgia e a reconstrução da abertura do conduto auditivo interno foi realizada com retalho vascularizado de dura-mater, músculo e cola de fibrina. RESULTADOS: A exérese foi completa em 99 por cento dos casos, com mortalidade de 1,6 por cento. Houve preservação da função do nervo facial em 85 por cento dos casos e da audição em 40 por cento dos pacientes com audição prévia e tumores menores de 1,5 cm. A incidência de fístula liquórica foi 5,8 por cento e meningite 2,9 por cento. Embolia gasosa foi registrada em 3 por cento dos casos, não associada à mortalidade. CONCLUSÃO: O tratamento cirúrgico dos SV utilizando-se a posição de mastóide tem várias vantagens, com baixa morbidade e mortalidade.

Fatal Venous Air Embolism during Lung Surgery / 대한마취과학회지

Venous air embolism (VAE) can be a lethal complication of surgical procedures during which (1) venous pressure at the site of surgery is subatmospheric or (2) air (or gas) is forced under pressure into a body cavity. We experienced a case of fatal massive venous air embolism during lung surgery in a 52 years old patient undergoing a right upper lobectomy and right lower lobe superior segment wedge resection for lung cancer. Anesthetic induction and the initial intraoperative course were completely uneventful until sudden severe hypotension and abrupt bradycardia occurred after artificial air insufflation into the intraabdominal cavity through the diaphragm to reduce the dead space of the thoracic cavity. We considered a venous air embolism as the etiology of these events and treated the patient with manual cardiac massage, various cardiotonic drugs and removal of air through the right atrium. The patient was extubated at 3 days after surgery and discharged from the hospital without the complication of the venous air embolism.

Changes of EKG and Arterial Blood Gas during PEEP by Venous Air Embolism in Rabbits / 대한마취과학회지

Positive end expiratory pressure (PEEP) has been used to prevent and treat venous air embolism in patients in the sitting position undergoing neurosurgical operations However, the safety of PEEP has recently been questioned, because of concern that PEEP might incresae right atrial pressure more than left atrial pressure, thereby predisposing patients with a probe-patent foramen ovale to paradoxical air embolism. But it is controversial and needs further evaluation. In a prior study in rabbits with various venous air volume, the authors found that suddenly decreased mean arterial pressure and arterial PO2 showed peaked P wave, arrhythmias, ST depression and premature ventricular contraction on the EKG. In the present study, the authors examined the effects of 0, 3 and 5 cmHO PEEP (PEEP0, PEEP3, and PEEP5,) in 30 rabbits positioned supine with intravenous 0.5 mg/kg of air injection. In a prior study, we found that 0.5 mg/kg of air injection has serious change but showed low mortality. The measurements were obtained by the precordial doppler ultrasound, end tidal PCO2, mean arterial pressure, arterial PCO2, arterial PO2, and EKG. The results were as follow; 1) Doppler ultrasound was the most sensitive device even with PEEP and end tidal PCO2 was higher with PEEP5 than with PEEP3 and PEEP0 after suddenly decreased by the air injection. In PEEP statistic singnificance was observed (p<0.05). 2) The mean arterial pressure was significantly decreased by the air injection in PEEP0 PEEP3 and PEEP5 but there were no significant differences in all groups. It seemed likely due to low PEEP. 3) In PaCO2, slightly higher PaCO2 was observed in PEEP5 than in PEEP3 and PEEP. No statistic significance was obaerved. In PaO2, significant decrease was observed in all group but in PEEP3 small decrease was observed. 4) The incidence of bradycardia and ST depression was less in PEEP3 and PEEP5 than in PEEP0. In PEEP5, PVC was appeared relatively short duration than other group due to the air lock phenomenon. It was suspeeted that air was more freely passed according to increased right ventricular pressure after air lock. Authors conclude that PEEP has a benefit effect for the prevention of venous air embolism but after the occurence there is little benefit in the treatment.

Changes of EKG & Arterial Blood Gas at Venous Air Embolism in Rabbits / 대한마취과학회지

After the hemodynamic comparison of venous air volume in 32 rabbits, the following conclusions were derived. 1) The precordial doppler ultrasonography was most sensitive and end titdal CO2 pressure was statistically decreased at 0.1 ml/kg of air. 2) The mean arterial pressure was suddenly decreased at 1 minute after injection of more than 0.25 ml/kg of air, and was furether reduced according to the time. 3) The arterial PCO2 was continuously increased and statistically different from 0.25 ml/kg of air, and the arterial PO2 was suddenly decreased to about 1/3 of the control data. 4) The pulse rate was statistically decreased at more than 0.5 ml/kg of air and shown peaked p wave, arrhythmias, ST depression and premature ventricular contraction on the EKG. There 4 dead rabbits at 1.0 ml/kg of air, so we could conclucle that the fatal dose of rabbits was more decreased than that of the dogs in venous air embolism.

A Comparative Study of Effects of Netroglycerin , Adenosine Triphosphate and Sodium Nitroprusside on the Hemodynamic and Blood Gas Analysis Changes during Epinephrine Infusion in Air Embolized Cats / 대한마취과학회지

Effects of nitroglycerin (NTC), adenosine triphosphate (ATP) and sodium nitroprusside (SNP) on the hemodynamic and blood gas analysis changes epinephrine (EPI) infusion is air embolized cats were investigated. Under the general anesthesia with pentobarbital and vecuronium cats were given 2~2.5 ml/kg of air via internal jugular vein and were resuscitated with EPI bolus injection. Thirty two cats were divided into 4 groups of 8 each. Each 4 groups, were administered saline (group1), NTG (group 2), ATP (group 3) and SNP (group 4) with EPI continuous infusion, respectively. The air shadow in the heart of cats was visualized C-arm image intensifier throught the study and all three vasodilators augmented the removal of air from the heart on C-arm image. All three vasodilators therapy groups produced statistically significant decrease in rate pressure product (p<0.05) but only NTG therapy group decreased heart rate (p<0.05). Central venous pressure were decreased in all three vasodilators therapy groups but only NTG therapy group was statistically significant (p<0.05). Only NTG therapy group increased both arterial (p<0.05) and venous oxgenation. These results indicate that NTG therapy group produced more prominant hemodynamic and blood oxygenation improvement than the other three groups. It is concluded that NTG with vasopressor therapy coude be recommended in venous air embolism.

A Comparative Study of Effects of Netroglycerin , Adenosine Triphosphate and Sodium Nitroprusside on the Hemodynamic and Blood Gas Analysis Changes during Epinephrine Infusion in Air Embolized Cats / 대한마취과학회지

Effects of nitroglycerin (NTC), adenosine triphosphate (ATP) and sodium nitroprusside (SNP) on the hemodynamic and blood gas analysis changes epinephrine (EPI) infusion is air embolized cats were investigated. Under the general anesthesia with pentobarbital and vecuronium cats were given 2~2.5 ml/kg of air via internal jugular vein and were resuscitated with EPI bolus injection. Thirty two cats were divided into 4 groups of 8 each. Each 4 groups, were administered saline (group1), NTG (group 2), ATP (group 3) and SNP (group 4) with EPI continuous infusion, respectively. The air shadow in the heart of cats was visualized C-arm image intensifier throught the study and all three vasodilators augmented the removal of air from the heart on C-arm image. All three vasodilators therapy groups produced statistically significant decrease in rate pressure product (p<0.05) but only NTG therapy group decreased heart rate (p<0.05). Central venous pressure were decreased in all three vasodilators therapy groups but only NTG therapy group was statistically significant (p<0.05). Only NTG therapy group increased both arterial (p<0.05) and venous oxgenation. These results indicate that NTG therapy group produced more prominant hemodynamic and blood oxygenation improvement than the other three groups. It is concluded that NTG with vasopressor therapy coude be recommended in venous air embolism.

A Comparative Study of The Effects of Norepinephrine , Isoproterenol & Nitroglycerin on The Hemodynamic and Blood Gas Analysis Changes in Air Embolized Cats / 대한마취과학회지

The effects of Norepinephrine(NE), Isoproterenol(ISO) and Nitroglycerin(NTG) on the hemodynamic, arterial and venous blood gas analysis changes in air embolized cats were investigated. Under general anesthesia with Halothane, cats were injected 1ml/kg of air acutely to decrease mean arterial pressure(MAP) about 30 to 40 percent of control value through superior vena cava. 14 cats were divided into two groups of 7 each (group 1 and 2). Group 1 cats received NE and then NE with NTG therapies. In group 2, ISO and then ISO with NTG therapies were taken. The results were as follows: 1) Hemodynamic changes. Group 1: NE increased the MAP from 69+/-8 mmHg(mean+/-SD) to 116+/-14mmHg(p<0.05), decreased the right atrial pressure(RAP) from 18+/-4mmHg to 11+/-3mmHg(p<0.05). Combined therapy with NTG decreased the MAP from 116+/-14 mmHg to 101+/-10 mmHg(p<0.05), the HR from 167+/-16 beats/min(bpm) to 150+/-4 bpm(p<0.05), the RAP from 11+/-3 mmHg to 8+/-3mmHg(p<0.05). Group 2: ISO increased the MAP from 81+/-8mmHg to 112+/-14 mmHg(p<0.05), and the HR from 152+/-21 bpm to 190+/-24 bpm(p<0.05). Combined therpy with NTG decreased the HR from 190+/-24 bpm to 174+/-19 bpm(p<0.05), the CVP from 14+/-7mmHg to 14+/-3mmHg(p<0.05), and the RAP from 13+/-3mmHg to 12+/-3mmHg(p<0.05). 2) Blood gas analysis changes. Group 1: NE with NTG combined therapy increased the arterial oxygen tension from 335+/-54 mmHg to 372+/-49mmHg, decreased the venous CO2 tension from 52+/-9mmHg to 47+/-4mmHg. Group 2: ISO with NTG combined therapy increased the arterial oxygen tension from 344+/-85mmHg to 375+/-50mmHgIp<0.05). (paired t-test, p<0.05). In conclusion, NE and ISO increased MAP in venous air embolism with moderately decreased MAP. Inotropic agent with NTG therapy improved arterial oxygenation.