Anaesthetic management of pregnant patients with cardiac implantable electronic devices: case reports and review.

Heart disease is a leading cause of maternal mortality and morbidity. Pregnant women with structural, conduction or degenerative cardiac disease who require rhythm control or who are at high risk of sudden cardiac death may carry a cardiac implantable electronic device or may occasionally require the insertion of one during their pregnancy. These women are now encountered more frequently in clinical practice, and it is essential that a multidisciplinary approach, beginning from the early antenatal phase, be adopted in their counselling and management. Contemporary cardiac rhythm control devices are a constantly evolving technology with increasingly sophisticated features; anaesthetists should therefore have an adequate understanding of the principles of their operation and the special considerations for their use, in order to enable their safe management in the peripartum period. Of particular importance is the potential adverse effect of electromagnetic interference, which may cause device malfunction or damage, and the precautions required to reduce this risk. The ultimate goal in the management of this patient subgroup is to minimise the disruption to cardiovascular physiology that may occur near the time of labour and delivery and to control the factors that impact on device integrity and function. We present the ante- and peripartum management of two pregnant women with an implantable cardioverter-defibrillator, followed by a review and update of the anaesthetic management of parturients with cardiac implantable electronic devices.

Anaesthetic management of parturients with univentricular congenital heart disease and the Fontan operation.

Women with a single ventricle circulation palliated with the Fontan operation require specialist multidisciplinary management. We report 14 such cases with successful pregnancies and detail the pathophysiology encountered. A combined obstetric and cardiac service between Chelsea and Westminster Hospital and Royal Brompton Hospital provides care for women with heart disease, and maintains a prospective database of referred women. We searched this database for women with a known Fontan circulation and reviewed the case notes and electronic patient records between January 1994 and December 2015. Eight women palliated with the Fontan operation delivered 14 live babies over the study period, with detailed peripartum management available for 11. Low-dose combined spinal-epidural or epidural labour analgesia was the intended mode of analgesia or anaesthesia for all deliveries (depending on clinical scenario and clinician preference), and was performed in 79%. Seven cases (50%) had a caesarean delivery. A neuraxial catheter technique was preferred (86%), whether or not vaginal delivery was attempted first. There were no deliveries under general anaesthesia. Fifty percent of cases were complicated by postpartum haemorrhage. Other peripartum complications included arrhythmias (29%), chest pain (14%) and intrauterine growth restriction (57%). Women with a Fontan circulation are increasingly encountered in obstetric practice. A good understanding of the underlying anatomy and its impact on physiology, coupled with meticulous care are essential to allow safe delivery for mother and baby. Multidisciplinary input into peripartum care is required, with anticipation of increased risk of complications such as haemorrhage and arrhythmias.

Spinal anaesthesia for caesarean section in the presence of respiratory failure and spinal metastases from a soft tissue clear cell sarcoma.

Spinal metastases occur in up to 70% of all patients with cancer. However, only 10% are symptomatic. Before considering central neuraxial blockade in patients with malignancy, a history of back pain should be excluded. Anaesthetists should be aware that intrathecal and epidural injections could cause paraplegia if metastases are impinging on the spinal cord. Failure to achieve adequate sensory anaesthesia after central neuraxial blockade or presentation with postoperative paraplegia may indicate the presence of asymptomatic vertebral canal metastases. In this report, the anaesthetic management of a patient with respiratory failure and spinal metastases from a soft tissue sarcoma, requiring caesarean section is described. Sensory anaesthesia extending above a level of imminent cord compression was achieved despite loss of cerebrospinal fluid signal on magnetic resonance imaging.

Practical management of the parturient with congenital heart disease.

Cardiac disease is becoming more common in women presenting for maternity care and is a major cause of maternal mortality in the UK. We present a review of the management of parturients with congenital heart disease, focusing on practical aspects and the problems that may be expected.

UK registry of high-risk obstetric anaesthesia: arrhythmias, cardiomyopathy, aortic stenosis, transposition of the great arteries and Marfan's syndrome.

The UK registry of high-risk obstetric anaesthesia was set up in late 1996 to collect reports of high-risk pregnancy, pool them into a central database and disseminate the results. At the time of analysis for this paper (December 31, 2001) 308 cardiorespiratory reports had been received. The five most common conditions, occurring in 125 cases (41% of the total), were arrhythmias (43 cases), cardiomyopathy (26 cases), aortic stenosis (24 cases), transposition of the great arteries (18 cases) and Marfan's syndrome (14 cases). We describe the features and management of these cases.

The anaesthetic management of a parturient with polymorphic catecholamine-sensitive ventricular tachycardia.

Polymorphic catecholamine-sensitive ventricular tachycardia is an uncommon but potentially life-threatening condition. There are few reports of this condition in pregnancy. It is one of five types of polymorphic ventricular arrhythmia, the others being long-QT syndrome, short coupled variant of torsade de point malignant disease, idiopathic ventricular fibrillation with normal ECG and Brugada syndrome. Exercise and stress can precipitate ventricular tachyarrhythmias in patients with polymorphic catecholamine-sensitive ventricular tachycardia and it is important to avoid increases in plasma catecholamine levels. We report on the anaesthetic management of a parturient with this condition, for elective caesarean section and discuss the stress response in parturients receiving regional and general anaesthesia.

UK registry of high-risk obstetric anaesthesia: report on cardiorespiratory disease.

Forms were sent to members of the Obstetric Anaesthetists' Association requesting information on cardiorespiratory disease in pregnancy. Reports of 274 pregnancies in 259 women were received over four years (1997-2000). There were 83 valve lesions, 52 complex congenital heart disease, 112 miscellaneous heart disease and 27 respiratory disease. Half the mothers were classified as New York Heart Association grade I, 29% grade II, 14% grade III, 5% grade IV and six unknown. Thirty-nine mothers were seen by an anaesthetist only just before delivery. Regional analgesia for labour was more likely to be planned for severe (82%) than for mild symptoms (55%; P=0.039), but severity of symptoms did not affect choice of anaesthesia for caesarean section. Eighty-one women were delivered by elective caesarean section, 59 by emergency caesarean section, 82 had spontaneous and 49 assisted vaginal delivery. Three women suffered miscarriages. Regional analgesia was used in 73% of vaginal deliveries, Entonox or pethidine in 15% and no analgesia in 12%. Spinal anaesthesia was used in 21% of caesarean sections, an incremental regional technique (incremental epidural or combined spinal-epidural) in 40% and general anaesthesia in 39%. Forty-three women were admitted to intensive care units electively and 10 unplanned. Ninety-five per cent survived pregnancy in the same state as antepartum, 2% deteriorated and seven died. Ninety-four per cent of babies (258 babies) were delivered in good condition, nine in poor condition and seven died. Despite lack of denominator data and potential biases among the reported cases, the Registry provides a valuable snapshot of current practice in the UK.

Dural puncture and iatrogenic pneumocephalus with subsequent transverse myelitis in a parturient.

PURPOSE: To report a case of transverse myelitis following inadvertent dural puncture and iatrogenic pneumocephalus and any possible causal relationship is explored. CLINICAL FEATURES: A 32-yr-old primigravida developed a severe headache associated with pneumocephalus following accidental dural puncture when the loss of resistance to air technique was used to locate the epidural space. She was treated with oxygen 100% to promote resorption of the air and the headache resolved. One month later she developed a sensory disturbance in her feet. Neurological examination revealed reduced sensation to cold and pain to ankle level and bilateral suppressed knee and ankle reflexes but was otherwise normal. A spinal cord lesion (epidural abscess/hematoma) was excluded with an emergency T1 and T2 weighted magnetic resonance imaging (MRI) scan of the lumbar spine. Over the next 48 hr the sensory disturbance worsened to involve her legs and waist. Examination revealed a sensory loss to waist level, reduced joint position sense and vibration sense in her lower limbs and absent knee and ankle reflexes bilaterally, but normal power in both her legs. A further full length T2 weighted MRI scan of the spine showed a small area of high signal at the level of T3 compatible with transverse myelitis. This was treated with high dose corticosteroids and her symptoms resolved over the next three months. CONCLUSION: The etiology of transverse myelitis after dural puncture in a parturient could not be identified nor could any causal link be established between the dural puncture, pneumocephalus, and subsequent transverse myelitis.

Efficacy and safety of the laryngeal mask airway vs Guedel airway following tracheal extubation.

PURPOSE: To compare the safety and efficacy of the laryngeal mask airway (LMA) with the Guedel airway during the recovery period. METHODS: In a prospective randomised trial in the Post Anesthesia Care Unit (PACU), 52 patients (ASA 1 and 2) were randomised to receive either a laryngeal mask airway (LMA: n = 26) or a Guedel airway (n = 26) during the recovery period after middle ear surgery. Ease of airway maintenance was graded and the presence of coughing was noted. Peripheral arterial oxygen saturation (SpO2) was measured continuously by pulse oximetry in the PACU. Readings were taken on arrival (time 0) and for five minutes afterwards. RESULTS: There was no difference in sex, age, weight or incidence of smoking between the two groups. In the LMA group 25 patients required no airway manipulation and only one patient required repositioning of the LMA. In the Guedel group severe difficulty maintaining the airway was experienced in two patients, moderate difficulty in five patients and mild difficulty in 12 patients. Seven patients required no airway manipulation. The LMA group showed higher ease of airway maintenance scores, (P = < 0.0001) and less coughing (P = 0.0496). At time 0 and at one minute the LMA group had higher median SpO2 (97% and 97%) than the Guedel group (95% and 96%), (P = 0.0002 and 0.0362). There was no further difference in SpO2. CONCLUSIONS: The LMA provides easier airway maintenance, less coughing and initially higher median SpO2 when compared with the Guedel airway in the recovery period.

Failed intubation and emergency percutaneous tracheostomy.

Failed intubation associated with difficulty with ventilation is rare. Cricothyrotomy may provide a means of oxygenating the patient, but in practice it may be difficult to perform and does not establish a definitive airway. We report two patients in whom percutaneous tracheostomy was used as an emergency procedure. In both cases placement was extremely rapid and salvaged the situation, leaving a definitive airway.