Comparison of Norepinephrine and Cafedrine/Theodrenaline Regimens for Maintaining Maternal Blood Pressure During
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IBIMA Publishing Obstetrics & Gynecology: An International Journal http://www.ibimapublishing.com/journals/GYNE/gyne.html Vol. 2015 (2015), Article ID 714966, 12 pages DOI: 10.5171/2015.714966 Research Article Comparison of Norepinephrine and Cafedrine/Theodrenaline Regimens for Maintaining Maternal Blood Pressure during Spinal Anaesthesia for Caesarean Section Hoyme, M.1, Scheungraber, C.2, Reinhart, K.3 and Schummer, W.3 1Department of Internal Medicine I (Cardiology, Angiology, Pneumology) Friedrich Schiller University, Jena, Germany 2Departments of Obstetrics and Gynecology, Friedrich Schiller University, Jena, Germany 3Clinic of Anaesthesiology and Intensive Care Medicine, Friedrich Schiller University, Jena, Germany Correspondence should be addressed to: Schummer, W.; [email protected] Received date: 9 January 2014; Accepted date: 4 April 2014; Published date: 26 August 2015 Academic Editor: Dan Benhamou Copyright © 2015. Hoyme, M., Scheungraber, C., Reinhart, K. and Schummer, W. Distributed under Creative Commons CC-BY 4.0 Abstract Common phenomena of spinal anaesthesia for caesarean sections are hypotension and cardiovascular depression, both of which require immediate action. Akrinor® (theodrenaline and cafedrine), a sympathomimetic agent commonly used in Germany for such cases, was phased out with little notice at the end of 2005. Phenylephrine was not and is not an approved drug. Norepinephrine became the first-line drug. The outcome in neonates delivered by elective caesarean section under spinal anaesthesia was studied. At our university hospital, all elective caesarean sections under spinal anaesthesia from 2005 and 2006 were analysed regarding hypotension and the vasopressor administered. If maternal arterial pressure decreased by more than 20% of baseline, patients in 2005 received Akrinor®; patients in 2006 received norepinephrine. Neonatal umbilical blood pH as well as Apgar scores at one, five and ten minutes after delivery were measured. Other than the vasopressor, all patients were treated and all data were collected in an identical manner, per our hospital’s Standard Operating Procedures (SOP). There were 251 patients eligible for the study; 123 in 2005 and 128 in 2006. A vasopressor was administered to 153 women for treatment of hypotention, 82 women (group A = Akrinor®) in 2005 and 71 women (group NE = norephinephrine) in 2006. There were no significant differences between the groups regarding arterial umbilical blood pH or Apgar scores. Despite treatment, prolonged hypotension (>10 minutes) occurred in both groups (group A: n=10; group NE: n=12). The neonatal arterial blood pH did not show any significant difference between the two groups. Two patients in group A, none in group NE, suffered from clinically relevant tachycardia (>50% increase of baseline). Our results thus suggest that norepinephrine is a safe vasopressor suitable for the treatment of peripartal hypotension without any risk of neonatal acidosis in elective caesarean section under spinal anaesthesia. Keywords: hypotension; Caesarean section; cafedrine, theodrenaline drug combination; norepinephrine. _____________ Cite this Article as : Hoyme, M., Scheungraber, C., Reinhart, K. and Schummer, W (2015), "Comparison of Norepinephrine and Cafedrine/Theodrenaline Regimens for Maintaining Maternal Blood Pressure during Spinal Anaesthesia for Caesarean Section," Obstetrics & Gynecology: An International Journal, Vol. 2015 (2015), Article ID 714966, DOI: 10.5171/2015.714966 Obstetrics & Gynecology: An International Journal 2 Introduction We then planned a study to compare Akrinor® to norephinephrine. Because Spinal anaesthesia, rather than general Akrinor® was no longer available for use anaesthesia, is the choice of modern after 2005; we were compelled to compare anaesthetic practice due to pregnancy- the 2005 Akrinor® results to the 2006 associated physiological changes which norephinephrine results. It is important to cause considerable risks regarding airway state that, other than the vasopressor management. It is the preferred method for administered, all patients in both years elective caesarean sections and is used in received identical treatment and all data 80-90% of the cases. Even spinal were collected in an identical manner, per anaesthesia, however, is not without risks. our hospital’s SOP. The present study Hypotension is one of the main risks of investigates differences in the way spinal anaesthesia in this setting and is Akrinor® and norepinephrine affect reported to occur in 80-90% of cases. umbilical arterial pH, Apgar scores, as well as the severity, frequency or duration of Caesarean sections normally require an hypotension. anaesthetic block at T4 level, i.e. an extensive sympathetic block with Methods decreased systemic vascular resistance and decreased venous return. Bearing in mind After approval of the study protocol by the that the mean arterial pressure is defined local ethics committee, we targeted all as cardiac output time’s systemic vascular women with singleton pregnancy who pre- resistance, one must consider that both of registered for elective Caesarean section in these parameters are influenced negatively. the years 2005 or 2006. (Sharwood-Smith and Drummond 2009) Blood supply and oxygenation of the foetus The data are collected and maintained in are dependent on the uteroplacental blood our de-identified data auditing process at flow. Since the latter is not auto-regulated, our hospital. Patients with cardiovascular a decrease in maternal blood pressure problems, pregnancy-induced results in a reduction of uteroplacental hypertension or contraindications to spinal blood flow and ultimately in impaired anaesthesia were not included. In 2005 the foetal oxygenation and (foetal) only vasopressor used was Akrinor® acidosis.(Shnider et al. 1993) This is the (group A); in 2006, only norepinephrine reason why maternal hypotension cannot was used (group NE). Patients not in need be tolerated and must be treated of a vasopressor were assigned to group A0 aggressively. A variety of vasopressors in 2005 and to group NE0 in 2006. have been used for this purpose. All women were treated according to the study protocol; i.e. our hospital’s SOP vial=20mg cafedrine and regulating spinal anaesthesia in caesarean ¹־ Akrinor® (1 10 1 mg theodrenaline) acts via beta sections. Premedication was administered stimulation and consecutively via cyclic upon the anaesthesiologist’s request and adenosine monophosphate, which leads to consisted of famotidine 20mg the night a positive inotropic action. As a before, and sodium citrate (20- 30 ml, 0.3 consequence, the stroke volume increases. M) on arrival at the operating room (OR). Heart rate and systemic vascular resistance Standard monitoring was in place when the are considered to remain unchanged. It patient arrived at the OR and consisted of was used to treat maternal hypotension non-invasive arterial blood pressure, during elective caesarean section in electrocardiography as well as pulse Germany for decades. (Clemens et al. 2010) oximetry. External cardiotocography (CTG) At the end of 2005, we were informed that was used to monitor the foetal heart rate. Akrinor® would be phased out by January After a five-minute rest, baseline arterial 2006. After considering various blood pressure and heart rate (HR) were alternatives, our choice was recorded. norepinephrine, a well- established catecholamine in clinical practice. _______________ Hoyme, M., Scheungraber, C., Reinhart, K. and Schummer, W (2015), Obstetrics & Gynecology: An International Journal , DOI: 10.5171/2015.714966 3 Obstetrics & Gynecology: An International Journal After thorough disinfection of the skin at hypertension. An increase of the heart rate the puncture site, a local anaesthetic was > 50% of baseline was considered reactive applied. Then a spinal needle (G25 or G27) tachycardia. was inserted at the L2/3 or L3/4 intervertebral space and a mixture of 2.5 Upon obstetricians’ request, ml hyperbaric 0.5% bupivacaine and 0.5 ml methylergometrine (0.2 mg) and oxytocine diluted morphine (=100 µg) was injected (10 IU) both diluted to 10 ml normal saline intrathecally. Then the patient was placed were given intravenously. Arterial blood in a supine position with slightly flexed samples from the umbilical cord were hips and knees, elevated upper body, and a preserved by clamping the same on both left lateral tilt of the table to prevent sides. A bedside blood gas analysis was inferior vena cava syndrome. The upper performed using point-of-care testing part of the body was held in an elevated (Radiometer, Copenhagen). An arterial pH position. Volume substitution was not value under 7.20 was considered as applied in advance of spinal anaesthesia acidosis. Furthermore, Apgar scores one, but followed the co-load type.(Dyer et al. five and ten minutes after delivery were 2004) Oxygen was administered to all determined by the obstetricians. The patients from the beginning of the obstetrician did not know what type or anesthesia when tolerated by the patient. dose of vasopressor, if any, had been We insisted on oxygen only in patients with administered. a SpO2 <95%. The caesarean section was performed after five to seven minutes with Statistics a sensory level of optimally T4, minimumly T6. Patients in both years, whether they received a vasopressor or not, were If systolic arterial blood pressure dropped compared with respect to size, weight and below 100 mmHg or by 20% of its baseline age using the Student t-test and the