Transcript USE OF LABETALOL FOR ATTENUATION OF HYPERTENSIVE …

USE OF LABETALOL FOR
ATTENUATION OF HYPERTENSIVE
RESPONSE TO ENDOTRACHEAL
INTUBATION IN PREECLAMPSIA
CO AUTHORS
PROF. DR.I.CHANDRASEKARAN MDDA
PROF. DR S.P.MEENAKSHISUNDARAM MDDA
ASST PROF. DR.G.VIJAYA MD
AUTHOR DR.H.VIJAYALAKSHMI MD PG
INSTITUTE OF ANAESTHESIOLOGY
MADURAI MEDICAL COLLEGE
INTRODUCTION
 LARNGOSCOPY AND INTUBATION LEAD TO
REFLEX CHANGES IN THE
CARDIOVASCULAR SYSTEM
 INCREASE IN BLOOD PRESSURE BY 40-50%,
20 % INCREASE IN HEART RATE
 MAY LEAD TO CONSEQUENCES LIKE
MYOCARDIAL ISCHEMIA ,CEREBRO
VASCULAR ACCIDENTS, PULMONARY
EDEMA
 HENCE STRESS ATTENUATION IS NEEDED
TO BLUNT THESE RESPONSES
AIM
 TO STUDY THE EFFECT OF
LABETALOL ON STRESS
ATTENUATION DURING
LARYNGOSCOPY IN PREECLAMPTIC
PATIENTS COMING FOR LOWER
SEGMENT CAESAREAN SECTION
METHOD
 ETHICAL COMMITTEE APPROVAL
 INFORMED WRITTEN CONSENT
 OBSERVATIONAL STUDY
 INCLUSION CRITERIA
 30 PREECLAMPTIC PATIENTS COMING FOR
LOWER SEGMENT CAESAREAN SECTION
 AGE- 20-35 YRS
 WEIGHT 50-70 KGS
EXCLUSION CRITERIA
 EVIDENCE OF ANTICIPATED
DIFFICULT AIRWAY
 BRONCHIAL ASTHMA
 HEART BLOCK
 DRUG ALLERGY
MONITORS
 PULSEOXIMETRY
 NON INVASIVE BLOOD PRESSURE
 CAPNOGRAPHY
PROCEDURE
 PATIENT POSITIONED SUPINE WITH
LEFT UTERINE DISPLACEMENT
 PREMEDICATION
 INJ.GLYCOPYRROLATE O.2MG
 INJ.RANITIDINE 50 MG
 INJ .METOCLOPROMIDE 10 MG
 INJ.LABETALOL 20MG SLOW IV 5MTS
BEFORE LARYNGOSCOPY
 INDUCED WITH INJ.THIOPENTONE
5MG/KG , SUXA 1.5MG/KG
 INTUBATED AND MAINTAINED WITH
O2,N2O
 INJ.FENTANYL ,ATRACURIUM USED IN
TITRATED DOSES
 REVERSED WITH INJ .NEOSTIGMINE
40µ/KG, GLYCOPYRROLATE 10µ/KG
 AFTER ADEQUATE ATTEMPTS PATIENTS
WERE REVERSED AND EXTUBATED
HEMODYNAMIC VARIABLES
MEASURED
 PULSE RATE
 SYSTOLIC BLOOD PERESSURE
 DIASTOLIC BLOOD PRESSURE
 OXYGEN SATURATION
PREOP, AT 1,3,5,10,20 ,30 ,60 ,120,180 MTS
 APGAR SCORE
HEART RATE
H
E
A
R
T
R
A
T
E
Time in minutes
SYSTOLIC BP
B
P
m
m
h
g
Time in minutes
DIASTOLIC BP
B
P
m
m
h
g
Time in minutes
SYSTOLIC & DIASTOLIC BP
B
P
m
m
h
g
Time in minutes
APGAR SCORE
 1 MINUTE – 7-8/10
 5 MINUTES- 8-10/10
OBSERVATION
 LABETALOL REDUCES HEART RATE
SYSTOLIC AND DIASTOLIC BLOOD
PRESSURE 10-15 % FROM BASELINE
 BLOOD PRESSURE LOWERING EFFECT
IS MAXIMUM 5-15 AFTER
ADMINISTRATION OF DRUG
LABETALOL
 α ,β BLOCKER
 RATIO OF β : α 3:1 ORAL
 RATIO OF β : α 7:1 IV
 HALFLIFE 4-6 HRS AFTER IV, 6 -8
HOURS AFTER ORAL
 ONSET IN 5 MTS , PEAK 5 – 15
MINUTES
 REDUCES SVR, REFLEX
TACHYCARDIA PRODUCED BY
VASODILATATION IS ATTENUATED BY
BETA BLOCKADE
 LIPID SOLUBLE ,50% PROTEIN BOUND
 F/M RATIO -0.2- 0.8
 NO REBOUND HYPERTENSION
 IT CROSSES HUMAN PLACENTA TO
PRODUCE CORD SERUM
CONCENTRATION AVERAGING 40-60%
OF PEAK MATERNAL LEVELS
 LOW PLACENTAL TRANSFER IS DUE
TO HIGH DEGREE OF IONISATION AT
PHYSIOLOGICAL PH
SUMMARY
 LABETALOL MINIMISES
CARDIOVASCULAR STRESS RESPOSE
TO LARYNGOSCOPY AND IUTUBATION
 REDUCES SYSTEMIC VASCULAR
RESISTANCE WITHOUT REFLEX
TACHYCARDIA
 LOW PLACENTAL TRANSFER
 IT DOES NOT CHANGE
UTEROPLACENTAL BLOOD FLOW
DESPITE DROP IN BP DUE TO
REDUCED PERIPHERAL VASCULAR
RESISTANCE
 REDUCES THE INCIDENCE OF
HYALINE MEMBRANE DISEASE IN
PREMATURE INFANTS BY INCREASING
SURFACTANT PRODUCTION DUE TO
ITS β2 AGONIST ACTIVITY
CONCLUSION
 LABETALOL IS AN EFFECTIVE DRUG
TO ATTENUATE THE HEMODYNAMIC
RESPONSE TO LARYNGOSCOPY AND
INTUBATION IN PREECLAMPTIC
PATIENTS
REFERENCES
 SEVERE HYPERTENSION IN PREGNANCY –
HYDRALAZINE OR LABETALOL A
RANDOMISED CLINICAL TRIAL – EUROPEAN
JOURNAL OF OBS AND GYN 128-2006
 CHANGES IN MATERNAL MIDDLE CEREBRAL
ARTERY BLOOD FLOW VELOCITY ASSOCIATED
WITH GA IN SEVERE PREECLAMPSIA-ANAES
ANALGESIA 88 1999
 FETAL OUTCOME IN A RANDOMISED
DOUBLE BLINDED CONTROLLED STUDY OF
LABETALOL VS PLACEBO IN PIH –BJOG
VOL 96 2005
 EFFECTIVE IN MANAGEMENT
 NO APPARENT DISADVANTAGE FOR THE FETUS
 LABETALOL VS METHYLDOPA IN THE
TREATMENT OF PIH
 INTERNATIONAL J OF OG VOL 49 1995
 QUICKER AND MORE EFFICIENT AT BP
CONTROL , BENEFICIAL EFFECT ON RENAL
BLOOD FLOW AND FEWER SIDE EFFECTS
THANK YOU