Bilateral paravertebral blockade for conventional cardiac surgery

Abstract

SummaryWe conducted a postal survey of cardiac anaesthetists in the UK, to determine the extent of magnesium sulphate (MgSO 4 ) use and the main indications for its administration. Questionnaires were sent to anaesthetists at 35 UK hospitals undertaking adult cardiac surgery. Responses were received from 24 hospitals (69%) totalling 124 individual responses. Twenty-five (20%) of the anaesthetists responding to the questionnaire routinely gave magnesium other than in cardioplegia. The most common indications for administration were arrhythmia prophylaxis and treatment, myocardial protection and the treatment of hypomagnesaemia.Keywords Anaesthesia; cardiovascular. Heart; arrhythmia, prevention. Ions; magnesium. Magnesium deficiency is common in hospitalised patients [1]. It may be related to diuretic and beta-blocker therapy, and is more common in the cardiac surgical population [2, 3]. Hypomagnesaemia is common following cardiopulmonary bypass (CPB), and persists into the postoperative period [4]. It is associated with a higher incidence of arrhythmias and a low cardiac index [2]. However, the routine administration of magnesium sulphate during cardiac surgery remains controversial. Several studies support its routine administration for arrhythmia prophylaxis [5][6][7][8], whereas others oppose this view [9, 10] and even suggest a detrimental effect from magnesium administration [11]. This survey was conducted to investigate the attitudes and current practice of cardiac anaesthetists in the UK to the routine administration of magnesium sulphate. MethodsFollowing approval from the Association of Cardiothoracic Anaesthetists (ACTA), postal questionnaires (Appendix) were sent to the ACTA contact in 35 adult cardiac surgery centres for distribution to consultant anaesthetists. The questionnaire was designed to examine the incidence of routine magnesium sulphate use, the dose and timing of its administration, the indications for its use, the frequency of serum magnesium measurements and the reasons for avoiding its routine use. ResultsReplies were received from 24 (69%) hospitals. A total of 124 individual questionnaires were completed. Of these, 25 (20%) of anaesthetists routinely administered magnesium sulphate.Of those who gave magnesium routinely, 76% administered it during CPB. The most common dose used was a 2-4 g (8-16 mmol) bolus. The main indications were arrhythmia prophylaxis, myocardial protection and suspected hypomagnesaemia associated with hypokalaemia and diuretic therapy. Several respondents commented on its usefulness in patients with poor left ventricular function and a reduction in inotropic support requirements post CPB.Thirty-six per cent of anaesthetists administer magnesium post CPB (24% during and post CPB), mainly as a bolus of 2-4 g. Indications given are arrhythmia prophylaxis and treatment, and measured hypomagnesaemia.Thirty-two per cent of anaesthetists administer it pre-CPB. A larger bolus dose of 5 g is most frequently given. The numerous indications stated include arrhythmia Anaesth...

Regional anesthesia for sternotomy and bypass—Beyond the epidural

“…The feasibility and efficacy of bilateral paravertebral block for conventional cardiac surgery was first studied by Canto in 107 adult patients undergoing cardiac surgery on cardiopulmonary bypass. In this observational study, bilateral paravertebral catheters were inserted either at third or fourth thoracic vertebrae and time to tracheal extubation, length of stay in the intensive care unit and the hospital, morbidity and mortality, and any complication attributable to the regional blockade were recorded.…”

The efficacy of paravertebral block using a catheter technique for postoperative analgesia in thoracoscopic surgery: a randomized trial☆

“…They found low pain scores during the intensive care unit stay, with good hemodynamic stability and a low complication rate [20].…”

Outcomes After Paravertebral Blocks

“…[16][17][18][19] Like an analgesic adjuvant, this technique has been used after multiple rib fractures, 20-22 thoracotomy, 8,23-26 minimally invasive cardiac surgery, 27,28 abdominal procedures, 29 renal colic, 30 closure of enterostomies, 31 ventral hernia repair, 32 for analgesia during labor, 33,34 and coronary artery bypass grafting. 35 The technique is particularly useful in high-risk patients in whom central neuraxial techniques pose increased risk such as hypertrophic cardiomyopathy and aortic stenosis. The technique can provide unilateral multisegment anesthesia and analgesia.…”