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 Table of Contents  
ORIGINAL ARTICLE
Year : 2017  |  Volume : 7  |  Issue : 1  |  Page : 26-32

Prophylactic crystalloids or prophylactic crystalloids with ephedrine: Comparison of hemodynamic effects during caesarean section under spinal anaesthesia using 0.5% bupivacaine


Department of Anaesthesiology, Karwar Institute of Medical Sciences, Karwar, Karnataka, India

Date of Web Publication1-Jun-2017

Correspondence Address:
Manjunath Timmappa Bhat
Department of Anaesthesiology, Karwar Institute of Medical Sciences, Karwar - 581 301, Karnataka
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/joacc.JOACC_37_16

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  Abstract 

Background: Spinal anaesthesia is usually chosen for caesarean section not only because of its faster onset and reliability but also because general anaesthesia is associated with more complications. However, hypotension is one of the most common complications of spinal anaesthesia in obstetric patients. Several measures have been devised to prevent hypotension, which include left uterine displacement, infusion of crystalloids before giving spinal anaesthesia (preloading) and administration of a prophylactic vasopressor. This study compared the hemodynamic effects of preloading crystalloids or crystalloids with ephedrine for caesarean section under spinal anaesthesia using 0.5% bupivacaine. Materials and Method: In this randomized, single blind, comparative clinical study, 80 parturients (American Society of Anesthesiologists grade 1) presenting for elective caesarean section under spinal anaesthesia were allocated to one of the two groups; group I received crystalloid preload and group II received crystalloid with ephedrine before spinal block. After institution of spinal anaesthesia in the lateral position with 2.0 ml (10 mg) of bupivacaine, 0.5% (heavy) using 25 G Quincke type spinal needle, parturients were made to assume a supine position with left lateral tilt. Heart rate, systolic blood pressure and diastolic blood pressure were monitored intraoperatively every 2 minutes till delivery and every 5 minutes after delivery. The amount of ephedrine used intraoperatively was also noted and compared among different groups. Results: Incidence of hypotension was 70% in the crystalloid group and 5% in the crystalloid with ephedrine group. This difference between the two groups was statistically significant (P < 0.001). The number of patients receiving rescue bolus of ephedrine was higher in the crystalloid group (40% before delivery and 30% after delivery) compared to crystalloid with ephedrine group (5% before delivery and none after delivery); the difference was statistically significant (P < 0.001). Sixteen patients (40%) in the crystalloid group experienced nausea compared to 6 patients (15%) in the crystalloid with ephedrine group; the difference was statistically significant with a P value of 0.012. Conclusion: This study demonstrates that prophylactic ephedrine given by infusion along with crystalloids is not only a simple and effective method for prevention of hypotension during spinal anaesthesia during elective caesarean section in ASA Grade I patients but also contributes to less incidence of intraoperative nausea and vomiting.

Keywords: Crystalloid, ephedrine, hypotension, spinal anaesthesia


How to cite this article:
Hegde BK, Bhat MT. Prophylactic crystalloids or prophylactic crystalloids with ephedrine: Comparison of hemodynamic effects during caesarean section under spinal anaesthesia using 0.5% bupivacaine. J Obstet Anaesth Crit Care 2017;7:26-32

How to cite this URL:
Hegde BK, Bhat MT. Prophylactic crystalloids or prophylactic crystalloids with ephedrine: Comparison of hemodynamic effects during caesarean section under spinal anaesthesia using 0.5% bupivacaine. J Obstet Anaesth Crit Care [serial online] 2017 [cited 2017 Aug 22];7:26-32. Available from: http://www.joacc.com/text.asp?2017/7/1/26/207392


  Introduction Top


Spinal anaesthesia is the most popular anaesthetic technique for caesarean section not only because it provides rapid, reliable and dense sensory and motor block but also because general anaesthesia is associated with higher maternal morbidity and mortality. Spinal anaesthesia is usually preferred for caesarean section because it allows the mother to be awake and interact immediately with her baby. Other advantages of spinal anaesthesia in an obstetric patient include speed of induction, reliability, minimal foetal exposure to the drug and reduced chances of aspiration.[1],[2] Hypotension is one of the most common complications of spinal anaesthesia in obstetric patients, and has been reported to be 90%.[3] Brief episodes of maternal hypotension result in decreased Apgar scores, prolonged time in achieving sustained respiration and also causes foetal acidosis.[4] Several measures have been devised to prevent hypotension, which include left uterine displacement, infusion of crystalloids before the administration of spinal anaesthesia (preloading) and administration of a prophylactic vasopressor.

Preloading involves administration of 0.5–2 L of crystalloids approximately 15–20 minutes before giving a spinal block.[5] This results in filling of capacitance vessels and limits hypotension when venodilation occurs. Ephedrine is the preferred vasopressor in pregnant patients because it maintains utero-placental blood flow.[6] It is an indirect acting non-specific adrenergic agonist which increases blood pressure mainly by increasing cardiac output (beta effect) and vasoconstriction (alpha effect). In low resource areas, it is a practice to add ephedrine to intravenous (IV) fluid bottle after subarachnoid block for caesarean section to prevent hypotension.

This study aimed to compare the effectiveness of preloading crystalloids or crystalloids with ephedrine in the prevention of hypotension following spinal anaesthesia for caesarean section.


  Materials and Methods Top


After obtaining institutional ethics committee approval and informed written consent from patients, this prospective, randomized study was performed. Eighty patients in the age group of 20–30 years, weighing 50–75 kg and belonging to American society of Anesthesiologists (ASA) grade I posted for elective lower segment caesarean section under spinal anaesthesia were included and randomly allocated into two equal groups, 40 in each group. Group I received crystalloid preload and group II received crystalloid with ephedrine before spinal block. Patients with known contraindications to spinal anaesthesia, those with comorbidities and those with obstetric complications were excluded from this study.

Pre-anaesthetic examination was carried out the previous day, and all the patients were asked to fast overnight. They were pre-medicated with Tab. ranitidine 150 mg PO the previous night and 2 h before surgery. The baseline heart rate (HR), systolic blood pressure (SBP) and diastolic blood pressure (DBP) were noted. Patients were then randomly allocated into two groups. After securing IV access with 18-gauge cannula, Group A (n = 40) received 10 ml/kg of ringer lactate solution as infusion over 10–15 minutes. A placebo (2 cc of normal saline) was added to the solution of patients in this group. Group B (n = 40) also received 10 ml/kg of ringer lactate solution as infusion to which 10 mg of ephedrine (2 cc of 5 mg/cc solution) was added and the solution was infused over 10–15 minutes before the initiation of the spinal block.

Spinal anaesthesia was then performed in the left lateral position with a 25 gauge Quincke type needle using midline approach at L4-5 interspace. Once free flow of cerebrospinal fluid (CSF) was seen, 10 mg of 0.5% hyperbaric bupivacaine hydrochloride was injected intrathecally over 15 seconds, after which supine position was assumed and left uterine tilt was given. Height of the block was tested by pinprick method using a blunt needle. Surgery was commenced when a sensory block up to T5 dermatome was reached. Baseline HR and BP were recorded by a non-invasive monitor before induction, every 2 minutes before delivery and every 5 minutes after delivery. Before delivery, 0 minute was taken as the time of administration of spinal anaesthesia. After delivery, the time of delivery was taken as 0 minute. All patients received oxygen at 5 L/min by facemask and SpO2 and electrocardiogram (ECG) monitoring was done continuously throughout the period of surgery.

SBP less than 90 mmHg or less than 30 mmHg from the baseline was defined as hypotension, and was promptly treated with IV fluids and 6 mg of IV ephedrine. HR less than 60 beats per minute was labelled as maternal bradycardia and was treated with 0.6 mg of IV atropine. SBP less than 85 mmHg was considered severe hypotension. Nausea was defined as an unpleasant sensation associated with urge to vomit, while vomiting was defined as forceful expulsion of gastric contents from the mouth. Systolic blood pressure above 140 mmHg or a diastolic blood pressure above 90 mmHg was labelled as hypertension.

Statistical analysis

Descriptive statistical analysis was carried out in the present study. Sample size was calculated taking into consideration the results obtained from a previous study. Based on the sample size formula for two independent groups (proportions), fixing alpha error at 0.05 and beta error at 0.20 and at 95% confidence interval, the minimum sample size obtained was 40 participants in each group. Hence, the total sample size was 80. Results on continuous measurements were presented as mean ± standard deviation (SD) (min–max), and results on categorical measurements were presented as number (%). Significance was assessed at 5% level of significance. Significance of continuous scale parameters between two groups (intergroup analysis) on metric parameters was done by Student's t-test (two tailed, independent). Homogeneity of variance was determined by Levene's test. Significance of categorical scale parameters between two or more groups was determined by Chi-square/Fisher exact test. Analysis of data was performed by SAS 9.2, SPSS 15.0, Stata 10.1, MedCalc 9.0.1, Systat 12.0 and R environment ver. 2.11.1 (IBM, USA). Graphs and tables were drawn using Microsoft Word and Excel.


  Results Top


In the crystalloid group, 52.5% were in the age group of 26–30 years and 47.5% were in the age group 20–25 years. In the crystalloid with ephedrine group, 45% were in the age group 26–30 years and 55% were in the age group 20–25 years. Mean ± SD was 25.25 ± 2.51 and 25.03 ± 2.92 in the crystalloid and crystalloid with ephedrine group, respectively. The participants were age matched with P = 0.391 [Table 1].
Table 1: Age distribution in the two groups of patients studied

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In the crystalloid group, 80% of the patients had height between 156 and 160 cm. In the crystalloid with ephedrine group, 87.5% of the patients had heights between 156 and 160 cm. Mean ± SD of height was 157.68 ± 2.38 and 157.88 ± 1.92 in the crystalloid and crystalloid with ephedrine group, respectively. The samples were height-matched with a P value of 0.680 [Table 2].
Table 2: Height distribution of patients studied

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Majority of the patients in both the groups weighed 55–60 kg (62.5% in the crystalloid group and 70% in the crystalloid with ephedrine group). Fifteen percent of the patients in the crystalloid group and 12% in the crystalloid with ephedrine group weighed 61–65 kg. Mean ± SD of weight was 60.44 ± 1.68 and 59.93 ± 1.98, respectively, in the crystalloid and crystalloid with ephedrine group. The samples were weight matched with a P value of 0.227 [Table 3].
Table 3: Weight distribution of patients studied

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Age, height, and weight characteristics were comparable in the two groups of patients. No significant differences were detected in maternal demographic data between the two groups [Table 4]. Sensory block was T5 in all the patients in both the groups. Apgar scores of neonates were 8 and above in both the groups.
Table 4: Age, height and weight of patients studied

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Baseline systolic blood pressure

Sixty-five percent patients in both groups had baseline SBP values of 121–130 mmHg. Twenty-five percent patients in the crystalloid group and 37.5% patients in the crystalloid with ephedrine group had baseline SBP values of 111–120 mmHg. Ten percent of the patients in the crystalloid group and 2.5% in the crystalloid with ephedrine group had baseline SBP values of 100–110 mmHg [Table 5] and [Graph 1].
Table 5: Baseline systolic blood pressure in the two groups of patients

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Baseline diastolic blood pressure

Seventeen patients in group I (42.5%) and 18 patients in group II (45%) had baseline DBP values of 81–90 mmHg. Sixteen patients in group I (40%) and 14 patients in group II (35%) had baseline DBP values of 71–90 mmHg. Five patients in group I (12.5%) and 4 patients in group II (10%) had baseline DBP values of 61–70 mmHg. Two patients in group I (5%) and 4 patients in group II (10%) had baseline DBP values of 50–60 mmHg [Table 6] and [Graph 2].
Table 6: Baseline diastolic blood pressure in the two groups of patients

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Heart rate

In the crystalloid group, 40% of the patients had HR of 91–110/min, 42.5% had 101–110/min and 5% in the range of 70–80/min. Crystalloid with ephedrine group had 25% of patients with HR of 111–120/min and 20% had 70–80/min [Table 7] and [Graph 3].
Table 7: Baseline heart rates in the two groups of patients

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Comparison of blood pressure in the two groups at specific time intervals

Before delivery, BP recordings every 2 minutes showed significantly lower readings in the crystalloid group of both SBP (starting from the 2nd minute and ending at 12th minute) and DBP (starting from the 2nd minute and ending at 8th minute) compared to those in the crystalloid with ephedrine group. After delivery, BP recordings done every 5 minutes showed significantly lower readings of both SBP and DBP in the crystalloid group (starting from the time of delivery and ending at 45th minute) compared to those in the crystalloid with ephedrine group [Table 8] and [Table 9], [Graph 4].
Table 8: Comparison of SBP at baseline, 0 minute, 8 minute before delivery and 30 minute after delivery

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Table 9: Comparison of DBP at baseline, 0 minute, 8 minute before delivery and 30 minute after delivery

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Before delivery, HR recordings every 2 minutes showed significant difference between the two groups only at the time of spinal anaesthesia (P = 0.041). After delivery, HR recordings every 5 minutes showed significant difference between the two groups only at the 30th minute (P = 0.037) and 40th minute (P = 0.025) [Table 10] and [Graph 5].
Table 10: Comparison of HR at baseline, 0 minute, 8 minute before delivery and 30 minute after delivery

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In total, 16 patients in the crystalloid group received a single bolus dose of 6 mg ephedrine before delivery and did not receive any further dose after delivery (total dose received during entire procedure = 6 mg). Ten patients in the crystalloid group who did not receive a bolus dose of ephedrine before delivery received it after delivery (total dose received during entire procedure = 6 mg). Two patients in the crystalloid group who received a single bolus dose of 6 mg ephedrine before delivery also received another single bolus dose of 6 mg ephedrine after delivery (total dose received during entire procedure = 6 mg before delivery + 6 mg after delivery = 12 mg).

Two patients in the Crystalloid with ephedrine group received a single bolus dose of 6 mg ephedrine before delivery and did not receive any further dose after delivery (total dose received during entire procedure = 6 mg). The difference between the two groups with respect to ephedrine received either before delivery or after delivery is statistically significant (P < 0.001) [Table 11], [Graph 6] and [Graph 7].
Table 11: Comparison of ephedrine (6 mg) given in two groups of patients

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  Discussion Top


Spinal anaesthesia is a simple, reliable and fast acting technique of anaesthesia for caesarean section. However, it has some common complications, most notably hypotension and bradycardia.[7] Combined effects of autonomic denervation and vagal nerve predominance leads to peripheral venous pooling, resulting in decrease in preload. Arteriolar vasodilatation causes decrease in after load, and blockade of cardioaccelerator fibres (T1–T4) results in bradycardia and decrease in contractility. Spinal anaesthesia-induced hypotension is treated physiologically by improving the venous return. This increases the preload and restores the cardiac output. However, mechanical methods such as head down position or leg elevation (10–15°) or leg wrapping with elastocrit bandages and splints have failed to be effective methods for prevention of hypotension.

Colloids are no better than crystalloids in reducing the incidence of hypotension. In addition, they are costlier compared to crystalloids, may cause anaphylactic reactions,[8] interfere with the clotting cascade [9] and blood grouping and cross matching. On the other hand, crystalloids are required in great volumes (>15 ml/kg) to decrease the incidence of hypotension.[10] These huge volumes have multiple adverse effects including increased central venous pressure, blood dilution leading to decrease in oxygen carrying capacity and release of atrial natriuretic peptide initiating diuresis, thereby mitigating the effect of volume load on blood pressure. Moreover, volume and speed of preload may be responsible for benefits of crystalloid preloads.[11] In addition, infusion of large volumes may result in unwanted delays in emergency cases.[12]

Prophylactic administration of intramuscular ephedrine has shown mixed results. Postoperative hypertension and erratic absorption from the injection site are its other problems. Intravenous bolus or infusions of ephedrine have been shown to reduce the chances of hypotension without unwanted side effects.

In our study, we compared the hemodynamic effects of preloading crystalloids or crystalloids with ephedrine before spinal anaesthesia. The incidence of hypotension in the crystalloid group was 70.0%, compared to 5% in the crystalloid with ephedrine group. This difference between the two groups is statistically significant (P < 0.001) [Table 12]. A Study by Chan et al.[13] demonstrated low incidence of severe hypotension in the ephedrine group compared to the fluid group (35% vs. 65%, P = 0.04) in a study comparing the efficacy of prophylactic ephedrine and fluid preload. Desalu et al.[14] compared the effectiveness of prehydration (1 L 0.9% saline before spinal block) with ephedrine infusion (ephedrine 30 mg in 1 L of 0.9% saline after spinal block) for caesarean section under spinal anaesthesia. Hypotension occurred in 70% of the patients in the crystalloid group and 40% of the patients in the ephedrine infusion group. In the above study, ephedrine as infusion with saline was given after spinal block compared to ephedrine with ringer lactate given before spinal block in our study. Moreover, 2.5 ml (12.5 mg) of 0.5% bupivacaine was used in this study compared to 2.0 ml (10 mg) in our study, which could probably explain a higher incidence of hypotension (40% vs. 5%) in the ephedrine group in the above mentioned study compared to our study. Kamat et al.[15] compared crystalloid preloading with ephedrine bolus and ephedrine infusion for caesarean section under spinal anaesthesia. Their results demonstrated that ephedrine bolus (6 mg) given at the start of the spinal block followed by infusion of 24 mg ephedrine later was better than crystalloid administration alone for preventing hypotension. The results seen in our study compare well with those reported by Chan et al.,[13] Desalu et al.[14] and Kamat et al.[15] who observed increased incidence of hypotension in the preload group compared to the ephedrine group.
Table 12: Comparison of hypotension and heart rate >100 and >120 in the two groups

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Forty percent of the patients in the crystalloid group in our study required vasopressor therapy before delivery, compared to 5% of the patients in the crystalloid with ephedrine group, which is statistically highly significant (P < 0.001**). After delivery, 30% of the patients in the crystalloid group required vasopressor therapy, compared to none in the crystalloid with ephedrine group. Two patients in the crystalloid group who received ephedrine 6 mg IV bolus before delivery also received another rescue dose of ephedrine 6 mg IV bolus after delivery. None in the crystalloid with ephedrine group who received a single bolus dose of ephedrine before delivery had to receive another bolus after delivery. Supplemental dose of intraoperative intravenous ephedrine was significantly lower in the ephedrine group in the studies by Chan et al., Desalu et al. and Kamat et al., which is consistent with our study.

None of the patients in either of the groups in our study developed hypertension. The minimum dose of ephedrine that has been used in this study may have contributed to this finding. Similarly, none of the patients in either group had bradycardia. In the crystalloid with ephedrine group, this may have been because of the chronotropic effect of ephedrine. Sixteen patients (40%) in the crystalloid group experienced nausea compared to 6 patients (15%) in the crystalloid with ephedrine group; the difference was statistically significant with a P value of 0.012 [Table 13]. Major cause of nausea and vomiting has been attributed to reduction in medullary blood flow to the chemoreceptor trigger zone. Increased gastric peristalsis due to preganglionic sympathetic denervation of the stomach may also contribute to nausea and vomiting during spinal anaesthesia. Studies by Gajraj et al.[16] and Vercauteren et al.[17] also showed lower incidence of nausea in the ephedrine group, which is consistent with our study.
Table 13: Comparison of nausea in the two groups of patients

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We derived results by using a smaller dose of ephedrine (10 mg), compared to higher doses used by some authors. Crystalloid volumes used by us are also lower (10 ml/kg) compared to larger volumes used in other studies. These results are highly encouraging as we have achieved comparable results by using a lesser quantity of drug as well as fluids thereby reducing the adverse effects of a larger dose, had it been used.

The limitation of our study was that we used a small dose of ephedrine (10 mg) in the crystalloid with ephedrine group. We do not know whether this small dose can contribute to foetal acidosis. Measurement of umbilical blood pH would have helped in its detection. Cord blood pH was not measured due to lack of facility.


  Conclusion Top


Prophylactic ephedrine given by infusion along with crystalloids is not only a simple, economical and more effective method than crystalloid prehydration alone in the prevention of hypotension during spinal anaesthesia for elective caesarean section in ASA Grade I patients but also contributes to lesser incidence of intraoperative nausea and vomiting.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

 
  References Top

1.
Gogarten W, Van Aken H. A Century of Regional Analgesia in Obstetrics. Anaesth Analg 2000;91:773-5.  Back to cited text no. 1
[PUBMED]    
2.
Bernards CM. Epidural and spinal anaesthesia. In: Barash PG, Cullen BF, Stoelting RK, editors. Clinical Anaesthesia, 4th ed. Philadelphia: Lippincott William and Wilkins; 2001. pp. 689-709.  Back to cited text no. 2
[PUBMED]    
3.
Mercier FJ, Bonnet MP, De la Dorie A, Moufouki M, Banu F, Hanaf A, et al. Spinal anaesthesia for caesarean section: Fluid loading, vasopressors and hypotension. Ann Fr Anesth Reanim 2007;26:688-93.  Back to cited text no. 3
[PUBMED]    
4.
Allan M Cyna, Marion Andrew, Richard S Emmett, Philippa Middleton, Scott W Simmons. In Cochrane database of systematic reviews (Online) 2006;4:CD002251.  Back to cited text no. 4
    
5.
Nishikawa K, Yokoyama N, Saito S, Goto F. Comparison of effects of rapid colloid loading before and after spinal anaesthesia on maternal hemodynamics and neonatal outcomes in caesarean section. J Clin Monit Comput 2007;21:125-9.  Back to cited text no. 5
    
6.
Macarthur A, Riley ET. Obstetric Anaesthesia controversies: Vasopressor choice for post spinal hypotension during caesarean delivery. Int Anaesthesiol Clin 2007;45:115-32.  Back to cited text no. 6
[PUBMED]    
7.
Arndt JO, Bomer W, Krauth J, Marquardt. B. Incidence and time course of cardiovascular side effects during spinal anaesthesia after prophylactic administration of intravenous fluids or vasoconstrictors. Anesth Analg 1998;87:347-54.  Back to cited text no. 7
    
8.
McHugh GJ. Anaphylactoid reaction to pentastarch. Can J Anaesth 1998;45:270-2.  Back to cited text no. 8
[PUBMED]    
9.
Caruso JL, Kirby RR. Fluid, electrolytes, blood, and blood substitutes. In: Kirby RR, Gravenstein. N, Lobato. EB, Gravenstein JS, editors. Clinical Anaesthesia Practice, 2nd edition. Philadelphia: W. B. Saunders Company; 2002. pp. 770-89.  Back to cited text no. 9
    
10.
Coe AJ, Revanas UB, Centrallaserettet KA. Is crystalloid preloading useful in spinal anaesthesia in the elderly? Anaesthesia 1990;45:241-3.  Back to cited text no. 10
    
11.
Reynolds F, Seed PT. Anaesthesia for caesarean section and neonatal acid-base status: A meta-analysis. Anaesthesia 2005;60:636-53.  Back to cited text no. 11
    
12.
Bouchnak M, Belhadj N, Chaaoua T. Azaiez W, Hamdi M, Maghrebi H. Spinal anaesthesia for caesarean section: Does injection speed have an effect on the incidence of hypotension? Ann Fr Anesth Reanim 2006;25:17-9.  Back to cited text no. 12
    
13.
Chan WS, Irwin MG, Tong WN, Lam YH. Prevention of hypotension during spinal anaesthesia for caesarean section: Ephedrine infusion versus fluid preload. Anaesthesia 1997;52:908-13.  Back to cited text no. 13
[PUBMED]    
14.
Desalu I, Kushimo OT. Is ephedrine infusion more effective at preventing hypotension than traditional prehydration during spinal anaesthesia for caesarean section in African parturients? Int J Obstet Anaesth 2005;14:294-9.  Back to cited text no. 14
[PUBMED]    
15.
Kamat S, Gupta R, Raju M. Prevention of hypotension following spinal anaesthesia for caesarean section: Comparison between crystalloid preloading & prophylactic ephedrine bolus & infusion. Karnataka Anaesth J 2009;10:4-8.  Back to cited text no. 15
    
16.
Gajraj NM, Victory RA, Pace NA, Van Elstraete AC, Wallace DH. Comparison of an ephedrine infusion with crystalloid administration for prevention of hypotension during spinal Anaesthesia. Anesth Analg 1993;76:1023-6.  Back to cited text no. 16
    
17.
Vercauteren MP, Copejans HC, Hoffmann VH, Adriaensen HA. Prevention of hypotension by single 5-mg dose of ephedrine during small-dose spinal anaesthesia in prehydrated caesarean delivery patients. Anesth Analg 2000;90:324-7.  Back to cited text no. 17
    



 
 
    Tables

  [Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6], [Table 7], [Table 8], [Table 9], [Table 10], [Table 11], [Table 12], [Table 13]



 

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