Maternal Pulmonary Edema During Fetoscopic Surgery

Acute Pulmonary Edema in Pregnancy - Fluid Overload or Atypical Pre-eclampsia

Acute pulmonary edema in pregnancy is a rare but life-threatening condition with high maternal and perinatal morbidity and mortality. Here we discuss a case of acute pulmonary edema in an antenatal woman with pregnancy complicated by chronic severe constipation, highlighting the importance of the need for close liaison between obstetricians and other specialties in the management of pregnant women.

Anesthesia for Maternal-Fetal Interventions: A Consensus Statement From the American Society of Anesthesiologists Committees on Obstetric and Pediatric Anesthesiology and the North American Fetal Therapy Network

Maternal-fetal surgery is a rapidly evolving specialty, and significant progress has been made over the last 3 decades. A wide range of maternal-fetal interventions are being performed at different stages of pregnancy across multiple fetal therapy centers worldwide, and the anesthetic technique has evolved over the years. The American Society of Anesthesiologists (ASA) recognizes the important role of the anesthesiologist in the multidisciplinary approach to these maternal-fetal interventions and convened a collaborative workgroup with representatives from the ASA Committees of Obstetric and Pediatric Anesthesia and the Board of Directors of the North American Fetal Therapy Network. This consensus statement describes the comprehensive preoperative evaluation, intraoperative anesthetic management, and postoperative care for the different types of maternal-fetal interventions.

New Trends in Fetal Anesthesia

Fetal anesthesia teams must understand the pathophysiology and rationale for the treatment of each disease process. Treatment can range from minimally invasive procedures to maternal laparotomy, hysterotomy, and major fetal surgery. Timing may be in early, mid-, or late gestation. Techniques continue to be refined, and the anesthetic plans must evolve to meet the needs of the procedures. Anesthetic plans range from moderate sedation to general anesthesia that includes monitoring of 2 patients simultaneously, fluid restriction, invasive blood pressure monitoring, vasopressor administration, and advanced medication choices to optimize fetal cardiac function.

Peri-operative management of percutaneous fetoscopic spina-bifida repair: a descriptive review of five cases from the United Kingdom, with focus on anaesthetic implications

We present a case-based review of the first five percutaneous fetoscopic in-utero spina bifida repair procedures undertaken in the UK. Our focus is on implications of anaesthesia and analgesia for the mother and fetus, provision of uterine relaxation and fetal immobilisation while providing conditions conducive to surgical access. Minimising risks for fetal acidosis, placental and fetal hypoperfusion, maternal and fetal sepsis and maternal fluid overload were the foremost priorities. We discuss optimisation strategies undertaken to ensure fetal and maternal well-being under anaesthesia, shortcomings in the current approach, and possible directions for improvement.

Anaesthesia for foetoscopic Laser ablation- a retrospective study

Background and Aims:

Twin pregnancy with monochorionic placenta may be associated with arteriovenous vascular anastomosis of the placental vessels resulting in twin-to-twin transfusion syndrome (TTTS) and twin reversed arterial perfusion syndrome (TRAP). Foetoscopic LASER ablation (FLA) is the treatment of choice in reducing foetal mortality related to this.

Methods:

A retrospective review of medical records of 41 FLA procedures for TTTS and TRAP were analysed for anaesthetic management. Thirty-four patients received subarachnoid block, three combined spinal-epidural block, three general anaesthesia and one local anaesthesia with sedation. Nitroglycerine 5 mg patch was used for tocolysis 1 h before the procedure and continued for 24–48 h postoperatively.

Results:

Bupivacaine was used in 34 patients, and ropivacaine in three patients. Mean dose of bupivacaine 0.5% was 2.43 ± 0.32 ml and ropivacaine 0.75% was 2.85 ± 0.19 ml. The mean duration of surgery was 117.07 ± 28 min. Mild hypotension occurred in all patients under spinal anaesthesia and was treated with vasopressors. The foetal outcome among all 41 patients were 13 delivered live twins, 15 had a single live baby with intrauterine death of other twin baby. In 12 patients, both babies were intrauterine death. One patient was lost for follow-up.

Conclusion:

Foetoscopic procedures can be done under central neuraxial block, however occasionally general anaesthesia may be required.

Maternal pulmonary oedema during foetoscopic surgery

We report a case of maternal pulmonary oedema necessitating intubation and ventilation with associated hyperchloraemic metabolic acidosis during foetoscopic laser surgery for twin-twin transfusion syndrome (TTTS), believed to be secondary to absorption of normal saline irrigation fluid. TTTS complicates 10% to 20% of monochorionic twin pregnancies and develops due to imbalanced vascular anastomoses and consequent unidirectional transfusion between the twins. The recipient is at risk of cardiac failure due to circulatory overload and the donor twin becomes hypoperfused. The recipient is polyhydramniotic and the donor is oligohydramniotic. Untreated severe TTTS has a mortality rate of up to 90%. Treatment options include delivery if viable, serial amnioreduction or foetoscopic laser ablation of the communicating vessels. Since the Eurofoetus study, laser ablation has been the mainstay of treatment for pre-viable TTTS, involving insertion of endoscopes transabdominally into the polyhydramniotic sac to allow visualisation and ablation of the anastosmotic vessels. Amnioreduction does not correct the underlying pathology and offers very little in advanced disease. Foetoscopic laser ablation leads to an improved survival past 28 days and a lower incidence of neurological complications compared to serial amnioreduction.

Maternal and fetal safety of fluid-restrictive general anesthesia for endoscopic fetal surgery in monochorionic twin gestations

STUDY OBJECTIVE

To review our experience with general anesthesia in endoscopic fetal surgery for twin-to-twin transfusion syndrome (TTTS), and to compare fetomaternal outcome before and after protocol implementation.

DESIGN

Retrospective impact study.

SETTING

University-affiliated medical center.

MEASUREMENTS

Data from 85 consecutive patients who underwent endoscopic laser ablation of placenta vessels for severe TTTS were studied. Outcomes were compared in patients before (2000-2007) and after (2008-2012) a change to strict intraoperative intravenous (IV) fluid and liberal vasopressor management. Perioperative parameters (IV fluid administration, vasopressor use, maternal hemoglobin [Hb] concentration); maternal complication rate (respiratory, hemorrhagic); pregnancy outcome; and fetal and neonatal survival were recorded.

MAIN RESULTS

Patients in the early group (2000-2007; n = 55) received 1634 ± 949 mL of crystalloid fluid intraoperatively, compared with 485 ± 238 mL (P < 0.001; Student's t test) given to the late group (2008-2012; n = 30). Maternal pulmonary edema and any respiratory distress were seen in 5.5% and 12.7% of patients in the early group, respectively, and in none of the late group patients (P < 0.05; Chi-square analysis).

CONCLUSIONS

A significant risk of maternal respiratory complications exists after general anesthesia for endoscopic fetal surgery. Judicious fluid management significantly decreases this risk.

Maternal hypotension during fetoscopic surgery: incidence and its impact on fetal survival outcomes

In this retrospective cohort study, we aimed to determine the incidence of intraoperative maternal hypotension during fetoscopic surgery for twin-twin transfusion syndrome (TTTS) and to evaluate the impact of intraoperative hypotension on fetal survival. A total of 328 TTTS patients with recipient twin cardiomyopathy who underwent fetoscopic surgery under epidural anesthesia were included. The exposure of interest was maternal medical therapy with nifedipine for the treatment of fetal cardiomyopathy. We found that intraoperative hypotension occurred in 53.4% (175/328 patients). There was no statistically significant difference in incidence of hypotension between nifedipine exposure and nonexposure groups (54.8% versus 50.8%, P = 0.479). However, the nifedipine exposure group received a statistically significant higher dose of phenylephrine (7.04 ± 6.38 mcg/kg versus 4.70 ± 4.14 mcg/kg, P = 0.018) and higher doses of other vasopressor, as counted by number of treatments (6.06 ± 4.58 versus 4.96 ± 3.42, P = 0.022). There were no statistically significant differences in acute fetal survival rate (within 5 days) and fetal survival rate at birth between hypotensive and nonhypotensive patients. We concluded that preoperative exposure to nifedipine resulted in increased intraoperative maternal vasopressor requirement during fetoscopic surgery under epidural anesthesia. In patients who had intraoperative maternal hypotension, there was no correlation between the presence of maternal hypotension and postoperative fetal survival.

Anesthesia for fetal surgery

Fetal surgery pushes the limits of knowledge and therapy beyond conventional paradigms by treating the developing fetus as a patient. Providing anesthesia for fetal surgery is challenging for many reasons. It requires integration of both obstetric and pediatric anesthesia practice. Two patients must be anesthetized for the benefit of one, and there is little margin for error. Many disciplines are involved, and communication must be effective among all of them. Conducting anesthetic research with vulnerable populations, such as the pregnant woman carrying a fetus with a birth defect is difficult, and many questions remain to be answered. Work is needed to study possible neurotoxicity caused by exposure of the developing brain to anesthetic agents. The effects of stress on the developing fetus also must be further delineated. Anesthetic techniques vary by institution, and prospective studies to determine optimal anesthetic regimens are warranted.

The art of fetoscopy: a step toward minimally invasive fetal therapy

PURPOSE

To study the feasibility, learning curve, and safety of fetoscopy, so that fetal surgery can be confidently performed in ongoing pregnancies.

METHODS

Fetoscopy was performed at 12-20 weeks of gestation, in 12 women with fetal congenital malformations and/or for termination of pregnancy, under local anesthesia using fine fetoscopes ranging from 1 to 2-mm diameter. The fetal parts and placenta were examined for clarity of vision, identification, and anomalies.

RESULTS

Fetoscopy required great skill, patience, and extensive use of ultrasound for correct orientation. Visualization was better with endoscope of 2-mm diameter. Laser coagulation of placental vessels using diode laser system was possible in the last two cases. There were no major complications.

CONCLUSIONS

Fetal endoscopy is a feasible procedure, safe in experienced hands but has an appreciable learning curve.

Twin-twin transfusion syndrome: an ethics-based and evidence-based argument for clinical research

Aspects of twin-twin transfusion syndrome (TTTS) diagnosis, treatment alternatives, and research opportunities were considered during a consensus conference that was held by the North American Fetal Therapy Network in 2009. A 3-member scientific consensus panel gathered data from expert conference presentations, postconference communications, and comprehensive scientific literature database searches to develop recommendations for TTTS diagnosis, therapy, and research. The panel recommends retaining the Quintero staging system until a superior system has been validated appropriately. It concludes that there is normative equipoise to justify the performance of randomized clinical trials to identify the optimal treatment strategy for mild TTTS. Recommendations for the design and conduct of clinical trials and observational studies are also provided.

Anesthesia for fetal surgery

Fetal surgery pushes the limits of knowledge and therapy beyond conventional paradigms by treating the developing fetus as a patient. Providing anesthesia for fetal surgery is challenging for many reasons. It requires integration of both obstetric and pediatric anesthesia practice. Two patients must be anesthetized for the benefit of one, and there is little margin for error. Many disciplines are involved, and communication must be effective. Conducting anesthetic research with vulnerable populations, such as pregnant women and their fetuses, is difficult, and many questions remain unanswered. Work must be done in the study of possible neurotoxicity caused by exposure of developing brain to anesthetic agents. The effects of stress on the developing fetus must also be further examined. Optimal anesthetic regimens remain to be determined.