Factors Affecting Maternal and Fetal Outcomes of Non-Obstetric Surgery and Anesthesia during Pregnancy: a Retrospective Review of Data at a Single Tertiary University Hospital

Anesthetic recommendations for maternal and fetal safety in nonobstetric surgery: a balancing act

PURPOSE OF REVIEW

Nonobstetric surgery during pregnancy is associated with maternal and fetal risks. Several physiologic changes create unique challenges for anesthesiologists. This review highlights physiologic changes of pregnancy and presents clinical recommendations based on recent literature to guide anesthetic management for the pregnant patient undergoing nonobstetric surgery.

RECENT FINDINGS

Nearly every anesthetic technique has been safely used in pregnant patients. Although it is difficult to eliminate confounding factors, exposure to anesthetics could endanger fetal brain development. Perioperative fetal monitoring decisions require an obstetric consult based on anticipated maternal and fetal concerns. Given the limitations of fasting guidelines, bedside gastric ultrasound is useful in assessing aspiration risk in pregnant patients. Although there is concern about appropriateness of sugammadex for neuromuscular blockade reversal due its binding to progesterone, preliminary literature supports its safety.

SUMMARY

These recommendations will equip anesthesiologists to provide safe care for the pregnant patient and fetus undergoing nonobstetric surgery.

Safety and efficacy of remifentanil target-controlled infusion for conscious sedation in a pregnant woman: a case report

BACKGROUND

Every year 2% of pregnant women undergo nonobstetric surgical interventions worldwide. According to the American College of Obstetricians and Gynecologists Committee on Obstetric Practice, pregnant women should never be denied the most appropriate surgical treatment, regardless of the trimester of pregnancy. However, additional attention should be paid during the first trimester since it has the highest risk of inducing teratogenic mutations; additionally, during the third trimester, due to the possibility of preterm birth and low birth weight of the newborn, great care should be paid.

CASE PRESENTATION

We present the case of a Caucasian 36-year-old woman during her 21st week of pregnancy, with a normal-sized fetus, according to the gestational age on ultrasound exam, and with no additional risk factors. The patient referred to an increasing nasal obstruction associated with rhinorrhea of the left nasal cavity. She also reported episodes of sleep apnea and hyposmia. The patient received a detailed otolaryngological examination, which allowed for identification of a mass within the left nasal cavity. The subsequent nasal endoscopy confirmed a grayish polypoid mass lesion with a multinodular surface occupying the entire left nasal fossa. The lesion totally obliterated the left maxillary sinus, resulting in obstruction of the anterior osteomeatal unit and ethmoidal sinusitis. She was referred for a functional endoscopic sinus surgery using analgosedation with remifentanil target-controlled infusion.

DISCUSSION AND CONCLUSION

To the very best of our knowledge, this is the first case described in English literature about the use of analgosedation with remifentanil target-controlled infusion for otolaryngology surgery, specifically in functional endoscopic sinus surgery. It could be an interesting option to avoid the use of inhaled anesthetics that could induce fetal damage, especially during the first months of pregnancy. Furthermore, patient intubation is not necessary, which avoids cases of difficult intubation or any trauma to the airways. An adequate informed consent and appropriate compliance are elements of paramount importance in tailoring the anesthetic strategy for pregnant women who need nonobstetric surgical management.

Non-obstetric surgery during pregnancy and the effects on maternal and fetal outcomes: A systematic review

BACKGROUND AND OBJECTIVE

Non-obstetric surgery is fairly common in pregnant women. We performed a systematic review to update data on non-obstetric surgery in pregnant women. The aim of this review was to evaluate the effects of non-obstetric surgery during pregnancy on pregnancy, fetal and maternal outcomes.

METHODS

A systematic literature search of MEDLINE and Scopus was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The search span was from January 2000 to November 2022. Thirty-six studies matched the inclusion criteria, and 24 publications were identified through reference mining; 60 studies were included in this review. Outcome measures were miscarriage, stillbirth, preterm birth, low birth weight, low Apgar score, and infant and maternal morbidity and mortality rates.

RESULTS

We obtained data for 80,205 women who underwent non-obstetric surgery and data for 16,655,486 women who did not undergo surgery during pregnancy. Prevalence of non-obstetric surgery was between 0.23% and 0.74% (median 0.37%). Appendectomy was the most common procedure with median prevalence of 0.10%. Near half (43%) of the procedures were performed during the second trimester, 32% during the first trimester, and 25% during the third trimester. Half of surgeries were scheduled, and half were emergent. Laparoscopic and open techniques were used equally for abdominal cavity. Women who underwent non-obstetric surgery during pregnancy had increased rate of stillbirth (odds ratio (OR) 2.0) and preterm birth (OR 2.1) compared to women without surgery. Surgery during pregnancy did not increase rate of miscarriage (OR 1.1), low 5 min Apgar scores (OR 1.1), the fetus being small for gestational age (OR 1.1) or congenital anomalies (OR 1.0).

CONCLUSIONS

The prevalence of non-obstetric surgery has decreased during last decades, but still two out of 1000 pregnant women have scheduled surgery during pregnancy. Surgery during pregnancy increases the risk of stillbirth, and preterm birth. For abdominal cavity surgery, both laparoscopic and open approaches are feasible.

Adverse Fetal Outcomes and Maternal Mortality Following Nonobstetric Abdominopelvic Surgery in Pregnancy: A Systematic Review and Meta-analysis

OBJECTIVE

To quantify the absolute risks of adverse fetal outcomes and maternal mortality following nonobstetric abdominopelvic surgery in pregnancy.

SUMMARY BACKGROUND DATA

Surgery is often necessary in pregnancy, but absolute measures of risk required to guide perioperative management are lacking.

METHODS

We systematically searched MEDLINE, EMBASE, and EvidenceBased Medicine Reviews from January 1, 2000, to December 9, 2020, for observational studies and randomized trials of pregnant patients undergoing nonobstetric abdominopelvic surgery. We determined the pooled proportions of fetal loss, preterm birth, and maternal mortality using a generalized linear random/mixed effects model with a logit link.

RESULTS

We identified 114 observational studies (52 [46%] appendectomy, 34 [30%] adnexal, 8 [7%] cholecystectomy, 20 [17%] mixed types) reporting on 67,111 pregnant patients. Overall pooled proportions of fetal loss, preterm birth, and maternal mortality were 2.8% (95% CI 2.2-3.6), 9.7% (95% CI 8.3-11.4), and 0.04% (95% CI 0.02-0.09; 4/10,000), respectively. Rates of fetal loss and preterm birth were higher for pelvic inflammatory conditions (eg, appendectomy, adnexal torsion) than for abdominal or nonurgent conditions (eg, cholecystectomy, adnexal mass). Surgery in the second and third trimesters was associated with lower rates of fetal loss (0.1%) and higher rates of preterm birth (13.5%) than surgery in the first and second trimesters (fetal loss 2.9%, preterm birth 5.6%).

CONCLUSIONS

Absolute risks of adverse fetal outcomes after nonobstetric abdom- inopelvic surgery vary with gestational age, indication, and acuity. Pooled estimates derived here identify high-risk clinical scenarios, and can inform implementation of mitigation strategies and improve preoperative counselling.

Neurodevelopmental outcomes after prenatal exposure to anaesthesia for maternal surgery: a propensity-score weighted bidirectional cohort study

Up to 1% of pregnant women undergo anaesthesia for non-obstetric surgery. This study investigated neurodevelopmental outcomes after prenatal anaesthesia for maternal surgery. A bidirectional cohort study of children born between 2001 and 2018 was performed: neurodevelopmental outcomes of children who had received prenatal anaesthesia for maternal surgery were prospectively compared with unexposed children, with exposure status being assessed retrospectively. Children exposed to anaesthesia for obstetric and fetal surgery were excluded. The primary outcome was the global executive composite of the behaviour rating inventory of executive function score. Our secondary outcomes were: total problems; internalising problems and externalising problems derived from the child behaviour checklist; psychiatric diagnoses; and learning disorders. In 90% of exposed children, there was a single mean (SD) antenatal anaesthesia exposure lasting 91(94) min. There was a broad spectrum of indications, with abdominal surgery being most frequent. Parents of 129 exposed (response rate 68%) and 453 unexposed (response rate 63%) children participated. There were no arguments for non-response bias. After propensity weighting, there were no statistically significant differences in primary outcome, with a weighted mean difference (95%CI) of exposed minus unexposed children of 1.9 (-0.4-4.2), p = 0.10; or any of the secondary outcomes. Sensitivity analyses confirmed the robustness. Exploratory analyses, however, showed significant differences in certain subgroups for the primary outcome, (e.g. for intra-abdominal surgery, exposure duration > 1 h) and some cognitive subdomains (e.g. working memory and attention). This bidirectional cohort study, the largest investigation on the subject to date, has found no evidence in the general population for an association between prenatal exposure to anaesthesia and impaired neurodevelopmental outcomes.

Risk of adverse fetal outcomes following nonobstetric surgery during gestation: a nationwide population-based analysis

BACKGROUND

Literature suggests that nonobstetric surgery during gestation is associated with a higher risk of spontaneous abortion, prematurity, and a higher cesarean section rate, but the direct impact on fetal outcomes is still unclear. In this study, we aimed to investigate whether nonobstetric surgery during pregnancy is associated with negative fetal outcomes by analysing a nation-wide database in Taiwan.

METHODS

This population-based retrospective observational case-control study was based on the linkage of Taiwan's National Health Insurance Research Database, Birth Reporting Database, and Maternal and Child Health Database between 2004 and 2014. For every pregnancy with nonobstetric surgery during gestation, four controls were randomly matched according to maternal age and delivery year. We estimated adjusted odds ratios (aOR) and 95% confidence intervals (CIs) of adverse fetal outcomes with the non-surgery group as the reference. The primary outcomes involved stillbirth, prematurity, low birth weight, low Apgar scores, and neonatal and infant death.

RESULTS

Among 23,721 identified pregnancies, 4,747 underwent nonobstetric surgery. Pregnancies with nonobstetric surgery had significantly higher risks of prematurity (aOR: 1.46; 95% CI: 1.31-1.62), lower birth weight (aOR: 1.49; 95% CI: 1.33-1.67), Apgar scores < 7 (1 min, aOR: 1.58; 95% CI: 1.33-1.86; 5 min, aOR: 1.34; 95% CI: 1.03-1.74), neonatal death (aOR: 2.01; 95% CI: 1.18-3.42), and infant death (aOR: 1.69; 95% CI: 1.12-2.54) than those without nonobstetric surgery after adjustment for socioeconomic deprivation, hospital level, and other comorbidities. Surgery performed in the third trimester was associated with a significantly increased rate of prematurity (aOR: 1.38; 95% CI: 1.03-1.85), but lower rates of stillbirth (aOR: 0.1; 95% CI: 0.01-0.75) and Apgar score < 7 at the 5^th minute (aOR: 0.2; 95% CI: 0.05-0.82), than surgery performed in the first trimester.

CONCLUSIONS

Pregnancies with nonobstetric surgery during gestation were associated with increased risks of prematurity, low birth weight, low Apgar scores, neonatal and infant death, longer admission, and higher medical expenses than those without surgery. Furthermore, surgery in the third trimester was associated with a higher rate of prematurity than surgery performed in the first trimester.

TRIAL REGISTRATION

Not applicable.

Neurodevelopmental effects of maternal blood pressure management with noradrenaline during general anaesthesia for nonobstetric surgery in the pregnant rabbit model

BACKGROUND

In pregnant women, anaesthesia-induced hypotension is commonly treated using phenylephrine or noradrenaline, the rationale being to maintain uterine perfusion pressure and thereby uterine blood flow. Evidence for this strategy during general anaesthesia for nonobstetric surgery is absent.

OBJECTIVE

To analyse the effects of treating anaesthesia-induced hypotension with noradrenaline on brain development of rabbit foetuses of mothers subjected to general anaesthesia for nonobstetric surgery. We hypothesised that treatment of maternal hypotension would improve foetal outcomes.

DESIGN

Randomised controlled laboratory study using 21 pregnant rabbits (does) at 28 days of gestation.

INTERVENTION

Two hours of sevoflurane anaesthesia for a laparotomy without treatment of anaesthesia-induced hypotension (hypotension group) or with maintaining maternal mean arterial pressure above 80% of the awake value using noradrenaline (noradrenaline group). In the control group, does remained untouched. At term, all pups were delivered by caesarean section. One day later, the neurobehaviour of the pups was assessed and brains were harvested.

MAIN OUTCOMES

Neuron density in the frontal cortex for the comparison of noradrenaline groups versus hypotension groups was the primary outcome; the neurobehavioural scores and other histological outcomes were secondary outcomes.

RESULTS

In the noradrenaline groups and hypotension groups, neuron density in the frontal cortex was similar (1181 ± 162 versus 1189 ± 200 neurons mm-2, P = 0.870). However, significantly less foetal survival, lower sensory scores in neurobehavioural assessment and less proliferation were observed in the noradrenaline group when compared with the hypotension group. Neuron densities in other regions, total cell densities, biometrics and synaptogenesis were not affected. There were no differences between the control group and hypotension group.

CONCLUSION

During general anaesthesia for nonobstetric surgery in rabbits, treatment of anaesthesia-induced hypotension using noradrenaline did not affect neuron densities but was associated with impaired foetal outcomes according to several secondary outcome parameters. Further studies are needed to investigate any clinical relevance and to determine the target blood pressure in pregnant women during general anaesthesia.