EL-MINIA MED. BULL. VOL. 20, NO. 2, JUNE, 2009
Ahmed
TREATMENT OF STRESS RESPONSE TO LARYNGOSCOPY AND
INTUBATION WITH MAGNESIUM SULPHATE
By
Abbady A. Ahmed
Department of Anesthesia and Intensive Care,
Sohag faculty of Medicine
ABSTRACT:
Background: This prospective, randomized double-blinded study was designed to
evaluate the efficacy of preoperative administration of magnesium sulphate in reducing
stress response to laryngoscopy and intubation.
Methods: Fifty adult patients were randomly assigned to one of two groups. The
magnesium group (25 patients) received 10% magnesium sulphate and the control
group (25 patients) received 0.9% sodium chloride in a double-blind manner. The
magnesium group received magnesium sulphate 50 mg kg_1, administered as a slow
intravenous bolus over a 10 min period before the induction of anesthesia. The same
volume of isotonic saline was administered to the control group. No surgical
manipulations were allowed till the end of magnesium sulphate infusion. Heart rate,
systolic, diastolic, mean blood pressure, ECG changes and oxygen saturation (SPo2)
were measured.
Results: Both groups were comparable as regard to the demographic data. In control
group there was a statistically significant increase in heart rate, systolic, diastolic and
mean arterial blood pressure from the base line, and the maximum increase was at 3
minutes after intubation (p value <0.05). There was statistically significant increase in
heart rate, systolic, diastolic and mean arterial blood pressure value in the control
group following laryngoscopy and intubation in comparison to the study group
(p<0.01).
Conclusions: the use of magnesium sulphate attenuates the stress response to
laryngoscopy and intubation.
KEY WORDS:
Magnesium sulphate
Laryngoscopy
Stress response
Intubation.
INTRODUCTION:
Laryngoscopy and intubation
violate the patient's protective airway
reflexes and lead to physiological
changes involving various systems of
the body. Reflex changes in the
cardiovascular system are most marked
after laryngoscopy and intubation and
lead to an average increase in blood
pressure by 40-50% and 20% increase
in heart rate 1.
I.V. magnesium sulphate may
be a good agent for deliberate
hypotension because magnesium intervenes in the activation of membrane
Ca ATPase and Na–K ATPase
involved in transmembrane ion
exchanges during depolarization and
repolarization phases, and thus act as a
stabilizer of cell membrane and
intracytoplasmic organelles2.
191
EL-MINIA MED. BULL. VOL. 20, NO. 2, JUNE, 2009
Magnesium also exerts its
effects on L-type calcium channels in
membranes and the sarcoplasmic
reticulum. By inhibiting the calcium
activation
dependent
upon
the
sarcoplasmic channel, magnesium
limits the outflow of calcium from the
sarcoplasmic reticulum3. In addition,
magnesium sulphate acts as a vasodilator by increasing the synthesis of
prostacyclin, as well as inhibiting
angiotensin
converting
enzyme
4
activity . Magnesium sulphate has
small, dose dependent myocardial
depressant effect 5. In another study,
the antagonist effect of magnesium at
N-methyl-D-aspartate
(NMDA)
receptors has led to studies of its
adjuvant effect in perioperative
analgesia6.
Ahmed
and the anaesthetist who was in charge
of the patients during the operation was
unaware of the study medication. The
magnesium group received magnesium
sulphate 50 mg kg_1, administered as a
slow intra-venous bolus over a 10 min
period before the induction of
anesthesia. The same volume of
isotonic saline was administered to the
control group. The patients were
premedicated with glycopyrolate 0.2
mg I.V. administered just before their
entry in the operation theatre. The
patients were induced with thiopentone
sodium 5 mg/kg after 4 minutes of
magnesium
sulphate
infusion.
Succinylcholine was given in a dose of
1-2
mg/kg.
Anaesthesia
was
maintained with nitrous oxide, 50% in
oxygen, Isoflurane 1.5% and vecuronium 0.1mg/kg. No surgical manipulations were allowed till the end of
magnesium sulphate infusion.. An
automatic noninvasive monitor (Nihon
Kohden, Japan) was used to monitor
Heart rate, systolic, diastolic, mean
arterial blood pressure; preoperatively,
before induction of anesthesia, and
every minute for 5 minutes after
laryngoscopy and intubation. ECG
changes and oxygen saturation (SPo2)
were monitored. Any adverse events or
side-effects were recorded during the
perioperative and postoperative periods.
Data were presented as mean ± SD.
Statistical analysis was performed
using the Statistical Package for the
Social
Sciences
(SPSS
10.0).
Differences between the two groups
were subjected to the independent ttest. Paired t-test was applied to
compare values of different observation time points with initial values.
A statistical significance was regarded
to any difference when p value <0.05.
PATIENTS AND METHODS:
This
is
a
prospective
randomized double-blinded clinical
study. After study approval from the
ethical committee of Sohag university
hospital and written informed consents
was taken, fifty patients belonging to
ASA grade I, II were included in the
study informed consent was obtained
from all of them. Exclusion criteria
included cardiovascular dysfunction,
atrioventricular block, hepatic, renal
or known allergy to magnesium
sulphate or other study drugs, diabetic
neuropathy, haematological disorders,
history of neuromuscular disease,
morbid obesity, pregnancy, prior
treatment with calcium channel
blockers, opioids and anticoagulants,
and patients receiving magnesium
supplementation, or drugs known to
have a significant interaction with
NMDAs. The patients were divided
randomly into two groups. The magnesium group (25 patients) received 10%
magnesium sulphate and the control
group (25 patients) received 0.9%
sodium chloride in a double-blind
manner. The solutions were prepared
RESULTS:
The
two
groups
were
comparable with respect to age, body
mass index (BMI), sex, and ASA
192
EL-MINIA MED. BULL. VOL. 20, NO. 2, JUNE, 2009
physical status (table 1). In magnesium
group there was no statistically
significant difference in heart rate,
systolic, diastolic and mean arterial
blood pressure from the base line (p
value >0.05) (figure 1, table 2). In
control group there was a statistically
significant increase in heart rate,
systolic, diastolic and mean arterial
blood pressure from the base line, and
the maximum increase was at 3
minutes after intubation (p value <0.05)
(figure 1, table 2). There was statis-
Ahmed
tically significant increase in heart rate,
systolic, diastolic and mean arterial
blood pressure value in the control
group following laryngoscopy and
intubation in comparison to the study
group (p<0.01) (figure 1, table 2). The
use of magnesium sulphate infusion
did not result in any kind of
arrhythmias. In patients of control
group undergoing laryngoscopy and
intubation there was 4 patients (16%)
showed ventricular ectopics and 3
patients (12%) showed dropped beats.
Table 1: Shows demographic data for magnesium and control patients.
MAGNESIUM
CONTROL
P<0.05
N=25
N=25
33±14
37.7±10
n.s
Age (years)
28.5±4
29.1±4
n.s
BMI(kg/m2)
15/10
14/11
n.s
Sex (male/female)
19/6
20/5
n.s
ASA I/II
Data are presented as mean±standard deviation; BMI: body mass index.
Heart rate changes for Magnesium and Control
Patients
pr
e
pr
e
op
er
at
ive
in
du
ct
io
n
1
m
in
ut
e
2
m
in
ut
e
3
m
in
ut
e
4
m
in
ut
e
5
m
in
ut
e
beat/minuts
140
120
100
80
60
40
20
0
Magnesium group
Control group
Figure 1: shows heart rate changes for magnesium and control patients.
193
EL-MINIA MED. BULL. VOL. 20, NO. 2, JUNE, 2009
Ahmed
Table 2: Shows hemodynamic changes for magnesium and control patients.
PREOP. PREIND. 1MIN 2 MIN 3 MIN 4 MIN 5 MIN
SAP 126 ±7
112 ±9
121±6 145 ± 159±12 138±9 135±9
Control
group
MAP
95±6
85±7
89±10 116±9 124±7 119±9 112±10
N=25
DAP
80±7
72±8
79±6
97±8
104±8
99±8
88±6
SAP
124±12
104±7
89±6
78±6
82±5
78±7
76±56
Magnesium
group
MAP
95±7
82±8
70±6 66±7.8 67±6.1 65±5.9 65±6.3
N=25
DAP 81±62
69±74
65±54 59±67 60±64 58±67 55±76
Data presents as mean±SD. SAP; systolic arterial blood pressure, MAP; mean arterial
blood pressure, DAP; diastolic arterial blood pressure, Preop; preoperative, Preind;
before induction of anesthesia.
systolic blood pressure after intubation.
Plasma concentrations of epinephrine
and norepinephrine were markedly
lower after intubation in the magnesium sulphate -treated group10. Puri et
al. compared hemodynamic changes
during anesthesia induction and
intubation after infusion of magnesium
sulphate or lidocaine. The group
treated with magnesium sulphate
showed a slight increase in mean
arterial pressure (MAP) and systemic
vascular resistance and no decrease in
cardiac output, as compared to the
lidocaine group, with equally good
control of increased heart rate11. In
another study, the group treated with
magnesium sulphate showed a lesser
hypertensive response during induction
compared to placebo, whereas early
reflex tachycardia was not controlled
by magnesium sulphate 12. Ashton et al.
found no increase in arterial pressure
or heart rate and a moderate decrease
of plasma catecholamine concentrations after intubation in a group
treated with magnesium sulphate alone
before intubation13. Also Elsharnouby1
concluded that continuous infusion of
magnesium sulphate led to a useful
reduction in MAP and heart rate14.
DISCUSSION:
Reflex
changes
in
the
cardiovascular system after laryngoscopy and intubation are most marked.
They manifest themselves in the form
of tachycardia, hypertension and
cardiac arrhythmias1, ectopics being
most common. Less commonly we
may encounter bradycardia as a result
of vagal stimulation during laryngoscopy. Therefore, the anesthesiologist
must be careful so as not to over treat
these responses and create more
difficulties then the original problem7.
A wide variety of pharmacological
agents were used to attenuate the
hemodynamic responses like esmolol7,
Fentanyl8, bupre-norphine4, alfentanyl9
etc. In our study, the magnesium group
received
magne-sium
sulphate
50mg/kg as a slow i.v. bolus in a 10
min period before the induction of
anesthesia. This resulted in a steady
and smooth reduction in arterial blood
pressure and reduced heart rate in with
catecholamine release. Magnesium
sulphate reduces this release by the
adrenal medulla and adrenergic nerve
endings. In a similar study, patients
received thiopental and Succinylcholine with or without magnesium
sulphate 60mg/kg at anesthesia
induction. Patients treated with
magnesium sulphate showed a lower
increase of heart rate and
We conclude that the use of
magnesium sulphate attenuates the
194
EL-MINIA MED. BULL. VOL. 20, NO. 2, JUNE, 2009
stress response to laryngoscopy and
intubation.
Ahmed
8. Kindler CH, Schumacher PG,
Schneider MC, Urwyler A. Effects of
intravenous lidocaine and/or esmolol
on haemodynamic responses to
laryngoscopy and intubation: a double
blind, controlled clinical trial. Journal
of Clinical Anaesthesia 1996; Sept;
8(6):491-6.
9. Korenga GM, Kirkpatrick A,
Lord JG, Barbaras E et al. Effect of
esmolol on tachycardia induced by
endotracheal intubation. Anesth Analgesia 1985; 64:185-304.
10. James MFM, Beer RE, Esser
JD. Intravenous magnesium sulfate
inhibits catecholamine release associated with tracheal intubation. Anesth
Analg 1989; 68:772–6.
11. Puri GD, Marudhachalam KS,
Chari P, Suri RK. The effect of
magnesium sulphate on hemodynamics
and its efficacy in attenuating the
response to endotracheal intubation in
patients with coronary artery disease.J
Anesth Analg 1998; 87: 808–11.
12. Yap LC, Ho RT, Jawan B, Lee
JH. Effects of magnesium sulfate
pretreatment on succinylcholine-facilitated
tracheal
intubation.
Acta
Anaesthesiol Sin 1994; 32: 45–50.
13. Ashton WB, James MFM,
Janicki P, Uys PC. Attenuation of the
pressor response to tracheal intubation
by magnesium sulphate with and
without alfentanil in hypertensive
proteinuric patients undergoing caesarean section. Br J Anaesth 1991; 67:
741–7.
14. Elsharnouby1 N. M, and M. M.
Elsharnouby. Magnesium sulphate as a
technique of hypotensive anaesthesia.
British Journal of Anaesthesia 2006:96
(6): 727–31.
REFERENCES:
1. Bruder N, Granthil C, Ortega
D. Consequences and prevention
methods of hemodynamic changes
during laryngoscopy and intubation.
Ann Fr Anaesth Reanim 1992;
11(1):57-71.
2. Telci L., Esen F., Akcora D.,
Erden T., Canbolat A. T. and Akpir K.
Evaluation of effects of magnesium
sulphate in reducing intraoperative
anesthetic
requirements.
British
Journal of Anaesthesia, 2002; 89:594602.
3. Reinhart RA. Clinical correlates of the molecular and cellular
actions of magnesium on the cardiovascular system. Am Heart J 1991;
121: 1513–21.
4. Sanders GM, Sim KM. Is it
feasible to use magnesium sulphate as
a hypotensive agent in oral and
maxillofacial surgery? Ann Acad Med
Singapore 1998; 27: 780–5.
5. Jee D., Lee D, Yun S. and Lee
C. Magnesium sulphate attenuates
arterial pressure increase during
laparoscopic cholecystectomy. Br J
Anaesth. 2009 Oct; 103(4):484-9.
Epub 2009 Jul 17.
6. Dube´ L, Granry JC. The
therapeutic use of magnesium in
anesthesiology, intensive care and
emergency medicine: a review. Can J
Anesth 2003; 50: 732–46.
7. Saif Ghaus M, Vinita S, Kumar
A, Wahal R., Bhatia V K, Agarwal J.
A study of cardiovascular response
during laryngoscopy and intubation
and their attenuation by ultrashort
acting b-blocker esmolol.Indian J.
Anaesth. 2002; 46 (2) : 104-106p.
195
‫‪Ahmed‬‬
‫‪EL-MINIA MED. BULL. VOL. 20, NO. 2, JUNE, 2009‬‬
‫الملخص العربى‬
‫معالجة رد اإلجهاد إلى منظار الحنجرة وادخال االنبوبة الحنجرية بسلفات الماغنسيوم‬
‫عبادى عبد الاله أحمد‬
‫قسم التخدير والعناية المركزة كلية طب سوهاج‬
‫الهدف من البحث ‪ - :‬إستععمل ستلتلا الملسيست فى تتى عخت تف رد اإلجهتلد إلتى ميرتلر الحيجتر‬
‫فادخل االيبفبة الحيجر ة‪.‬‬
‫طرق البحث فأدفاعه ‪ - :‬عى إجراء هذا البحث على خمسفن مر ضل بللغتل سستمف بلتع علتفا ى‬
‫إلى مجمفعع ن‪.‬‬
‫مجمفعة سلتلا الملسيس فى ‪ 25‬مر ض أختذا ‪ %01‬ستلتلا الملسيست فى فالمجمفعتة الي لست ة‬
‫‪ 25‬مر ض أخذ ا ‪ 1.0‬علفر د الصفد فى‪.‬‬
‫الي لسلا ‪ - :‬فجد ز لد هلمة بلع إحصل ى تى معد ضربلا اليلت فضتغط التدى االييبلضتى‬
‫فااليبسلطى فمعفسط ضغط الدى تى المجمفعة الي لس ة بللميلرية بمجمفعة سلتلا الملسيس فى‪.‬‬
‫فجد تى هذه الدراسة أن إسععمل سلتلا الملسيس فى ختف من رد اإلجهلد إلى ميرلر الحيجر‬
‫ف ادخل االيبفبة الحيجر ة‪.‬‬
‫‪196‬‬