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Differences in Blood Pressure in Infants After General Anesthesia Compared to Awake Regional Anesthesia (GAS Study-A
M E McCann1, D E Withington, S J Arnup
1From the *Department of Anesthesiology, Perioperative and Pain Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts; †Department of Anesthesia, Montreal Children's Hospital, Montreal, Canada; ‡Department of Anesthesia, McGill University, Montreal, Canada; §Clinical Epidemiology and Biostatistics Unit, Murdoch Children's Research Institute, Melbourne, Victoria, Australia; ‖Anaesthesia and Pain Management Research Group, Murdoch Children's Research Institute, Melbourne, Victoria, Australia; ¶Department of Anaesthesia and Pain Management, the Royal Children's Hospital, Melbourne, Victoria, Australia; #Department of Paediatrics, University of Melbourne, Melbourne, Victoria, Australia; **Department of Anaesthesia, Istituto Giannina Gaslini, Genoa, Italy; ††Academic Unit of Anaesthesia, Pain and Critical Care, University of Glasgow, Glasgow, United Kingdom; ‡‡Department of Anaesthesia, Royal Hospital for Sick Children, Glasgow, United Kingdom; §§Department of Neonatal Medicine, The Royal Children's Hospital, Melbourne, Victoria, Australia; ‖‖Neonatal Research Group, Murdoch Children's Research Institute, Melbourne, Victoria, Australia; ¶¶Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts; ##Department of Psychiatry, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts; ***Department of Environmental Health, Harvard T. H. Chan School of Public Health, Boston, Massachusetts; †††Departments of Anesthesiology and Pediatrics, Children's Hospital Colorado, University of Colorado School of Medicine, Aurora, Colorado; ‡‡‡Department of Anaesthesia, Royal Children's Hospital, Melbourne, Australia; §§§University Medical Center Groningen, Groningen University, the Netherlands; ‖‖‖Pharmacology, Pharmacy, Anaesthesiology Unit, School of Medicine and Pharmacology, the University of Western Australia, Perth, Western Australia, Australia; ¶¶¶Department of Anaesthesia and Pain Management, Princess Margaret Hospital for Children, Perth, Western Australia, Australia; ###Department of Anaesthesiology and Intensive Care, Paediatric Intensive Care Unit Children Hospital 'Vittore Buzzi', Milano, Italy; ****Department of Anesthesiology and Pain Management, University of Texas Southwestern and Children's Health Medical Center, Dallas, Texas; ††††Outcome Research Consortium, Cleveland, Ohio; ‡‡‡‡Department of Anaesthesiology, Wilhelmina Children's Hospital, University Medical Center Utrecht, Utrecht, the Netherlands; §§§§Brain Center Rudolph Magnus, University Medical Centre Utrecht, the Netherlands; and ‖‖‖‖Department of Anesthesia, Sophia Children's Hospital, Erasmus Medical Center Rotterdam, the Netherlands.
Insights
Regional anesthesia (RA) significantly reduces intraoperative hypotension in infants undergoing inguinal hernia repair compared to general anesthesia (GA). RA also lowers the need for interventions to manage hypotension during surgery.
Area of Science:
- Pediatric Anesthesiology
- Surgical Outcomes
- Neurodevelopmental Research
Background:
- The General Anesthesia compared to Spinal anesthesia (GAS) study investigates neurodevelopmental outcomes at 5 years.
- A secondary aim of the GAS trial analyzes intraoperative hypotension rates and risk factors.
Purpose of the Study:
- To compare rates of intraoperative hypotension between general anesthesia (GA) and regional anesthesia (RA) in infants.
- To identify risk factors associated with intraoperative hypotension in this population.
Main Methods:
- 722 infants undergoing inguinal herniorrhaphy were randomized to either RA (bupivacaine) or sevoflurane GA.
- Hypotension defined as mean arterial pressure <35 mm Hg (any) or <35 mm Hg (moderate).
- Analysis primarily used intention-to-treat (ITT) and secondarily per-protocol.
Main Results:
- GA was associated with a 2.8-fold increased risk of hypotension compared to RA (ITT analysis).
- Incidence of any hypotension was 87% with GA vs. 41% with RA; moderate hypotension was 49% vs. 16% (ITT).
- GA, infant weight, and low intraoperative temperature were risk factors for hypotension; interventions were more frequent with GA.
Conclusions:
- Regional anesthesia (RA) significantly reduces the incidence of intraoperative hypotension in young infants undergoing inguinal hernia repair.
- RA also decreases the likelihood of requiring interventions to manage hypotension compared to sevoflurane anesthesia.
Background:
The General Anesthesia compared to Spinal anesthesia (GAS) study is a prospective randomized, controlled, multisite, trial designed to assess the influence of general anesthesia (GA) on neurodevelopment at 5 years of age. A secondary aim obtained from the blood pressure data of the GAS trial is to compare rates of intraoperative hypotension after anesthesia and to identify risk factors for intraoperative hypotension.
Methods:
A total of 722 infants ≤60 weeks postmenstrual age undergoing inguinal herniorrhaphy were randomized to either bupivacaine regional anesthesia (RA) or sevoflurane GA. Exclusion criteria included risk factors for adverse neurodevelopmental outcome and infants born at <26 weeks of gestation. Moderate hypotension was defined as mean arterial pressure measurement of <35 mm Hg. Any hypotension was defined as mean arterial pressure of <45 mm Hg. Epochs were defined as 5-minute measurement periods. The primary outcome was any measured hypotension <35 mm Hg from start of anesthesia to leaving the operating room. This analysis is reported primarily as intention to treat (ITT) and secondarily as per protocol.
Results:
The relative risk of GA compared with RA predicting any measured hypotension of <35 mm Hg from the start of anesthesia to leaving the operating room was 2.8 (confidence interval [CI], 2.0-4.1; P < .001) by ITT analysis and 4.5 (CI, 2.7-7.4, P < .001) as per protocol analysis. In the GA group, 87% and 49%, and in the RA group, 41% and 16%, exhibited any or moderate hypotension by ITT, respectively. In multivariable modeling, group assignment (GA versus RA), weight at the time of surgery, and minimal intraoperative temperature were risk factors for hypotension. Interventions for hypotension occurred more commonly in the GA group compared with the RA group (relative risk, 2.8, 95% CI, 1.7-4.4 by ITT).
Conclusions:
RA reduces the incidence of hypotension and the chance of intervention to treat it compared with sevoflurane anesthesia in young infants undergoing inguinal hernia repair.
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