The use of remifentanil during general anaesthesia for caesarean delivery in two patients with severe heart dysfunction

Preeclamptic heart failure - perioperative concerns and management: a narrative review

Preeclampsia is an important cause of heart failure during pregnancy and the postpartum period. The aim of this review is to elucidate the pathophysiology and clinical features of preeclamptic heart failure and describe the medical and anesthetic management of these high-risk parturients. This article reviews the current evidence base regarding preeclamptic heart failure and its pathophysiology, types, and clinical features. We also describe the medical and anesthetic management of these patients during the peripartum period. Heart failure due to preeclampsia can present as either systolic or diastolic dysfunction. The management strategies of systolic heart failure include dietary salt restriction, diuresis, and cautious use of beta-blockers and vasodilators. Diuretics are the mainstay in the treatment of diastolic heart failure. In the absence of obstetric indications, vaginal delivery is the safest mode of delivery in these high-risk patients, and the use of an early labor epidural for analgesia is recommended. These patients would require increased invasive monitoring during labor and vaginal delivery. Neuraxial and general anesthesia have been used successfully for cesarean section in these patients but require crucial modifications of the standard technique. Uterotonic drugs have significant cardiovascular and pulmonary effects, and a clear understanding of these is essential during the management of these patients. Preeclamptics with heart failure require individualized peripartum care, as cardiac decompensation is an important risk factor for maternal and neonatal morbidity and mortality. These high-risk parturients benefit from timely multidisciplinary team inputs and collaborated management.

Care for the Obstetric Patient with Complex Cardiac Disease

The prevalence of cardiac disease-related maternal morbidity and mortality is on the rise in the United States. To ensure safe management of pregnancy in patients with cardiovascular disease, pre-delivery evaluation by a multidisciplinary Pregnancy Heart Team should occur. Appropriate anesthetic, cardiac, and obstetric care are essential. Risk stratification tools evaluate the etiology and severity of cardiovascular disease to determine the appropriate hospital type and location for delivery and anesthetic management. Intrapartum hemodynamic monitoring may need to be intensified, and neuraxial analgesia and anesthesia are generally appropriate. The anesthesiologist must be prepared for obstetric and cardiac emergencies.

The use of remifentanil during general anesthesia for caesarean section

PURPOSE OF REVIEW

The purpose is to review the neonatal and maternal effects of remifentanil given at induction of general anesthesia for caesarean section and prior to delivery of the baby.

MAIN FINDINGS

Remifentanil seems to have short-lived respiratory depressant effects in approximately 50% of neonates, requiring short periods of mask ventilation or tactile stimulation of the neonate. Remifentanil produces excellent maternal hemodynamic stability avoiding tachycardia and hypertension, possibly reducing the risk of maternal awareness.

SUMMARY

Remifentanil can be safely used at induction of general anesthesia provided healthcare workers are available to manage short-lived neonatal depression.

Difficult intubation in a parturient with syringomyelia and Arnold-Chiari malformation: Use of Airtraq laryngoscope

Anesthetic technique in parturient with syringomyelia and Arnold–Chiari malformation is variable depending on the teams. Difficult intubation is one of the risks when general anesthesia is opted. Different devices have been used to manage the difficult intubation in pregnant women. We report the use of Airtraq™ laryngoscope after failed standard laryngoscopy in a parturient with syringomyelia and Arnold–Chiari type I malformation.

Remifentanil use for cesarean section in a patient with intracranial re-ruptured arteriovenous malformation

We describe the successful administration of remifentanil as part of the anesthetic technique used for cesarean section performed under general anesthesia in a 24-year-old woman with intracranial re-hemorrhage caused by re-ruptured arteriovenous malformation. A low dose of remifentanil was useful to obtund the hypertensive response during induction and maintenance of anesthesia without neonatal respiratory depression.

High output cardiac failure in a parturient with hereditary haemorrhagic telangiectasia

Hereditary haemorrhagic telangiectasia is a genetic condition which results in arteriovenous malformations involving the skin, mucous membranes, lung, brain, gastrointestinal tract, liver and spinal canal. The shunting of blood through arteriovenous malformations, especially in the liver,; leads to maldistribution of cardiac output. In order to supply blood to vital organs, cardiac output is increased through vasodilation, elevated stroke volume and elevated heart rate. Pregnancy can worsen the effects of the arteriovenous malformations. We present the peripartum management of a woman with hereditary haemorrhagic telangiectasia predominantly involving the liver that resulted in high output cardiac failure during two consecutive pregnancies.

Cesarean section and primary pulmonary hypertension: the role of intravenous dexmedetomidine

Primary pulmonary hypertension is a fatal disease that frequently becomes evident in pregnancy. The management of pregnant women with primary pulmonary hypertension poses a number of difficult problems, especially where regional anesthesia is considered to be contraindicated. A 30-year-old woman who developed primary pulmonary hypertension at 23 weeks of pregnancy was transferred to our hospital. Systolic pulmonary artery pressure and plasma brain natriuretic peptide levels were markedly elevated. Nitric oxide inhalation and prostacyclin prevented the progression of cardiac failure and reduced both plasma brain natriuretic peptide and pulmonary artery pressure. Cesarean section was performed at 32 weeks under general anesthesia. A combination of nitric oxide, prostacyclin, nitroglycerin, and dobutamine were administered during surgery. Intravenous dexmedetomidine was specifically used during emergence and recovery from anesthesia. This provided effective pain relief and hemodynamic stability. Throughout the clinical course, brain natriuretic peptide levels was monitored and used as an indicator of cardiac failure.

Remifentanil for cesarean section under general anesthesia: effects on maternal stress hormone secretion and neonatal well-being: a randomized trial

BACKGROUND

Remifentanil may attenuate maternal hemodynamic response during cesarean section under general anesthesia, but could cause transient but significant neonatal depression. We investigated the effect of low-dose remifentanil on maternal neuroendocrine response and fetal wellbeing.

METHODS

Forty-two ASA I-II parturients undergoing cesarean section at term under general anesthesia were randomized to receive either fentanyl after delivery (n=21, group C) or remifentanil bolus 0.5 microg/kg before induction followed by a continuous infusion at 0.15 microg x kg(-1)min(-1) until peritoneal incision, then restarted after delivery (n=21, group R). Maternal heart rate and blood pressure, and epinephrine, norepinephrine, adrenocorticotropic hormone (ACTH), and growth hormone levels were measured at baseline, uterine incision, and the end of surgery. Remifentanil was measured in maternal and umbilical arterial and venous blood. One- and 5-minute Apgar scores and umbilical arterial and venous pH were recorded.

RESULTS

ACTH was significantly higher in group C at uterine incision (P<0.01). No significant differences were observed in hemodynamics, catecholamines or growth hormone. Apgar scores at 1 (P<0.05) and 5 min (P<0.01) were significantly higher in group C. Mean umbilical pH values were within normal range but significantly higher in group C. Three neonates in group R required intubation but recovered at 5 min without naloxone. Mean+/-SD maternal remifentanil concentration was 1.67+/-1.04 ng/mL.

CONCLUSIONS

Remifentanil administration before peritoneal incision partially reduced the hormonal stress response. Maternal benefits must be weighed against transitory but significant neonatal respiratory depression. Neonatal resuscitation facilities are mandatory when remifentanil is used.

The use of remifentanil in obstetrics

Remifentanil has been proposed as the most suitable systemic opioid for use in obstetrics. Although the onset and offset are rapid, it cannot achieve maximum effect within the time period of a single uterine contraction. Nevertheless, it provides worthwhile analgesia mainly for the first stage of labor with consistently high maternal satisfaction. Maternal oxygen desaturation limits the dose and suitable monitoring during use is advised. As an adjunct to general anesthesia, it is successful in blunting responses to airway manipulation and providing hemodynamic stability in high-risk women. Neonatal effects when used in labor are minimal, but when combined with general anesthesia neonatal depression is unpredictable and more likely with an infusion dose greater than 0.1 microg/kg/min.

[Remifentanil bolus for cesarean section in high-risk patients: study of 12 cases]

OBJECTIVES

To evaluate the utility and safety of remifentanil for hemodynamic control during cesarean section in high-risk patients ineligible for spinal anesthesia.

METHODS

One minute before induction we injected a bolus of 1 microg x kg(-1) of remifentanil, followed by propofol (2.5 mg x kg(-1)), succinylcholine (1 mg x kg(-1)), cisatracurium, sevoflurane in oxygen and nitrous oxide, and fentanyl (5 microg x kg(-1)) after clamping the umbilical cord. We recorded maternal hemodynamic variables, pulse oximetry, capnography, bispectral index, and presence of muscular rigidity. In the neonate we assessed fetal wellbeing, weight, and requirement for naloxone. Hemodynamic stability was defined as no more than 15% variation in arterial pressure with respect to baseline.

RESULTS

Twelve patients undergoing surgery because of placenta abruptio, subarachnoid hemorrhage, HELLP syndrome, or preeclampsia were enrolled. Hemodynamic variables were consistently stable during surgery in all patients. No cases of neonatal rigidity were noted and there was no need for naloxone. The mean Apgar score was 6.42 (1.5) at 1 minute and 8.42 (0.9) at 5 minutes.

CONCLUSION

Bolus injection of 1 microg x kg(-1) of remifentanil may be useful for maintaining maternal hemodynamic stability in high-risk obstetric cases. Given the risk of neonatal depression, this resource should be used selectively and the means for neonatal resuscitation should be available.

Répercussions maternelles et néonatales de l'anesthésie générale par rémifentanil pour césarienne programmée

OBJECTIVE

Opioids are routinely omitted at the induction of general anesthesia for Caesarean delivery because of the risks of respiratory neonatal depression. The short-acting opioid remifentanil may afford advantages at the induction and surgical stimulation, without subsequent neonatal depression.

PATIENTS AND METHODS

In this double-blinded study, 40 at term women undergoing elective Caesarean section and requiring general anaesthesia were allocated randomly to receive either remifentanil (0,5 microg/kg) at the induction of anaesthesia (G1, n=20) or placebo (G2, n=20). Induction of anaesthesia was performed with propofol 2 mg/kg and succinylcholine 1 mg/kg. Anaesthesia was maintained with nitrous oxide in oxygen (50/50%, v/v), propofol (100 microg/kg/min), remifentanil (0.2 microg/kg/min) and atracurium. Neonates were assessed by using Apgar scores, possible respiratory depression, with or without ventilation in the mask or intubation and umbilical cord blood gas (artery: UA and vein: UV). Values are expressed as mean values +/-SD. Pearson's Chi squared and t-test were used for statistical analysis P<0.05 was considered significant.

RESULTS

Maternal systolic pressure, mean pressure and heart rate were significantly higher in G1 at induction. Apgar scores, heart and respiratory rate were similar between groups. Seven episodes of respiratory depressions were noted (3 in G1, 4 in G2). Five neonates required only brief assisted ventilation by face-mask (2 in G1, 3 in G2).

CONCLUSION

Remifentanil (0.5 microg/kg) at the induction of anaesthesia in elective Caesarean section under general anaesthesia can be used without subsequent neonatal depression. However, we believe that further research is necessary to extrapolate these results to a pregnancy carrying an acutely distressed foetus.

Caesarean section using total intravenous anaesthesia in a patient with Ebstein’s anomaly complicated by supraventricular tachycardia

Ebstein's anomaly is a rare congenital cardiac defect associated with both displacement and incompetence of the tricuspid valve. The condition is commonly complicated by supraventricular tachycardias. We describe the management of a patient with this condition undergoing caesarean section. Propofol and remifentanil total intravenous anaesthesia resulted in haemodynamic stability and delivery of a healthy baby who breathed spontaneously after two minutes.

LC–MS Determination of remifentanil in maternal and neonatal plasma

An HPLC-MS with electrospray ionization method for the determination of remifentanil in human plasma samples, pre-treated with SPE cartridge, has been developed and validated. Ionisation was performed by positive-ion electrospray and quadrupole filter mass spectrometer operated in the single ion-recording mode. Pre-treatment was performed using Waters Oasis((R)) SPE cartridges. Chromatographic separation was achieved in isocratic elution using a X-Terra C8 5 microm, 150 mm x 2.1 mm i.d. column. The mobile phase consisted of a mixture of water, methanol and acetonitrile (86:10:4, v/v/v) containing 0.1% of formic acid. The method showed to be linear in the range between 0.5 and 48.0 ng/ml, the estimated LOD is 0.18 ng/ml and the LOQ is 0.5 ng/ml. The method can be used to quantify remifentanil in plasma samples taken from adult and newborn patients in a range suitable for clinical studies.

Low-dose sequential combined spinal-epidural: an anaesthetic technique for caesarean section in patients with significant cardiac disease

In the United Kingdom, cardiac disease is the second most common cause of all maternal deaths. The best anaesthetic technique for caesarean section in these patients has yet to be established. We describe a low-dose combined spinal-epidural technique in four high-risk obstetric patients who presented to this unit. Invasive monitoring was used in each case, and drugs with significant cardiovascular effects were avoided or used with extreme caution. Multidisciplinary team involvement, including serial echocardiography in the antenatal period, is strongly recommended.

General anesthesia with remifentanil for Cesarean section in a patient with HELLP syndrome

HELLP syndrome is a severe complication of pre-eclampsia characterised by hemolysis, elevated liver enzymes and a low platelet count. It is associated with an increased risk of adverse outcome for both the mother and the fetus. Patients with HELLP syndrome are also at greater risk of pulmonary edema, adult respiratory distress syndrome, abruptio placentae, intracerebral hemorrhage, eclamptic convulsions, disseminated intravascular coagulation, ruptured liver hematomas and acute renal failure. Perinatal mortality is equally high. Before delivery, aggressive obstetric management is directed toward stabilization of the affected organ systems, if possible, and interruption of the pregnancy in the early phase of the accelerated disease progression. Definitive therapy is delivery. Parturients HELLP syndrome often require general anesthesia for Cesarean section delivery. The anesthetic technique is critical for these patients with a high risk of uncontrollable hypertension, bleeding and multiple organ failure. Remifentanil is increasingly used as a very short analgesic agent providing cardiovascular stability in high-risk patients. We report the management of a patient presenting in labor with HELLP syndrome, and describe the successful use of remifentanil as part of the anesthetic technique for her subsequent Cesarean section.

[Management of delivery in patients with Marfan's syndrome presenting aortic dilatation]

OBJECTIVE

We report the anesthesic and obstetrical management of two pregnant patients with Marfan's syndrome. An important dilatation of the root of aorta was established at the beginning of the pregnancy. Based on a review of the literature and our experience, we searched for clues to identify the ideal term and the best mode of delivery, and which type of anesthesia may be the more appropriate in patients with aortic dilatation.

RESULTS

No consensus can be found in the literature as far as anesthesia and obstetric management of these patients is concerned. Pregnancy must be continued as long as possible to ensure adequate fetal growth but fetal extraction should not be delayed if the diameter of the aorta enlarges too much. A diameter of 40 mm is probably the higher limit to accept for vaginal delivery. Beyond, cautious cesarean section would be advisable. In the absence of dural ectasia or a technical problem, neuraxial anesthesia is a good option.

CONCLUSION

According to the severity of the aortic dilatation and its evolution, specific management, based on good cooperation between obstetricians and anesthesiologists, is the key of a successful and safe childbirth.

General anaesthesia with target controlled infusion of propofol for planned caesarean section: maternal and neonatal effects of a remifentanil-based technique

The present case series evaluated maternal and neonatal effects of remifentanil, combined with propofol, during general anaesthesia for caesarean delivery. Following written informed consent, ten patients scheduled for semi-elective caesarean section were recruited to this prospective, unblinded trial. All patients with non-reassuring fetal status were excluded. A 0.50-micrograms/kg bolus of remifentanil was given intravenously, followed by a continuous infusion of 0.20 micrograms.kg(-1)min(-1). Anaesthesia was induced using propofol target controlled infusion set at a blood concentration of 5 micrograms/mL, 45 s after the remifentanil bolus. Following tracheal intubation the propofol target was reduced to 2.5 micrograms/mL and remifentanil maintained at 0.20 micrograms.kg(-1)min(-1). Mean arterial pressure remained stable throughout anaesthesia. Two patients experienced episodes of hypotension (mean arterial pressure decrease >20%). Although neonatal depression occurred in six babies and assisted mask ventilation was required briefly, recovery was rapid without the need for naloxone or tracheal intubation. Umbilical artery pH was >7.20 in all infants. We conclude that the results of the present case series using a remifentanil/propofol-based technique of general anaesthesia for caesarean section provide a basis to study the safety of this technique in a larger population. Under the conditions of the present trial, this anaesthetic technique seems safe for mother and infant, provided adequate precautions are taken to manage brief, self-limiting infant respiratory depression. At the moment we cannot advise the routine use of this technique, especially since it has not been studied in situations of fetal compromise.

Labor analgesia for the parturient with cardiac disease: what does an obstetrician need to know?

Maternal heart disease complicates 0.2-3% of pregnancies. The optimal management of the pregnant patient with cardiac disease depends on the cooperative efforts of the obstetrician, the cardiologist and the anesthesiologist involved in peripartum care. A comprehensive understanding of physiology of pregnancy and pathophysiology of underlying cardiac disease is of primary importance in provision of obstetric analgesia or anesthesia for this high-risk group of patients. This article will review the current guidelines and standards pertinent to management of obstetric analgesia and anesthesia in parturients with cardiac disease.

Neonatal chest wall rigidity following the use of remifentanil for cesarean delivery in a patient with autoimmune hepatitis and thrombocytopenia

Remifentanil is a useful adjunct in general anesthesia for high-risk obstetric patients. It provides effective blunting of the rapid hemodynamic changes that may be associated with airway manipulation and surgical stimulation. There have been no previous reports of opioid-related rigidity in the neonate delivered by a parturient receiving intraoperative remifentanil. We present a case of short-lived neonatal rigidity and respiratory depression following remifentanil administration during cesarean section to a parturient with autoimmune hepatitis complicated by cirrhosis, esophageal varices and thrombocytopenia.