Anesthetics Management for Neonates with Gastroschisis Repair
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Transcript of Anesthetics Management for Neonates with Gastroschisis Repair
Anesthetics Management for Neonates with Gastroschisis
Repair
Claire Yang, SRNADuke UniversityClass of 2013
Objectives
Differentiate between gastroschisis and omphalocele
Temperature regulation of the neonate
Identify correct strategies for fluid management
List the preop considerations, possible intraop complications, and postop anesthetic care
Gastroschisis & Omphalacoele
Gastroschisis Omphalocoele
Covering sac Absent Present
Fluid & Heat losses More Less
Surgical emergency Yes* No
Etiology Infarction of omphalomesenteric artery
Failure of gut migration from yolk sac into abdomen
Age when defect occurs
After 10 weeks 10 weeks
Congenital anomalies Rare Cardiac*
Condition of bowel ThickenedInflamed
Looks normal
Gastroshisis1 birth per 10,000, male > female
Young maternal age <20, cigarette smoking, preterm, and low birth weight
Often diagnosed with routine ultrasound
When? Where? How to deliver?
HypothermiaLarge surface area to body weight ratio
Less SQ fat to insulate
Infants less than 3 months cannot shiver
Immature SNS, can’t control vasoconstriction
Greater skin permeability to water
Exaggerated by the exposed bowel
Non-shivering ThermogenesisInfants respond to cold by increasing the production of
norepinephrine
This increases the metabolism of brown fat
ThermoregulationBrown Adipose Tissue (Brown Fat)
Found in newborn and hibernating mammals
Develops at 26 to 30 weeks of gestation
5% of total weight
Midscapular, back of the neck, clavicles, axillae, mediastinum, kidneys, and adrenal glands
Abundance of mitochondria, glycogen stores, blood supply to generate body heat
ReviewFour Mechanism of Heat Loss
How to Warm? Warm OR to 75-80*F
Heat lamps
Bair Hugger blanket
Plastic
Fluid warmer
Post-Delivery ManagementBegin in delivery room before coming to the OR
Assess V/S and early stabilization (oxygenation, intubation*, ventilation, IV access*)
Place gastric tube to decompress the stomach
Cover bowels with warm, moist, sterile dressing
Cover the entire lower body with a sterile plastic bag
Transfer to OR or other facilities in the incubator
Avoid further trauma to bowel during transport (twisted bowel can result in ischemia)
Preop AssessmentGestational age? Term or preterm? Weight?
Vitamin K? Surfactant?
If intubated already, check the ETT size and position
If not intubated, continue respiratory assessment (SaO2 on routine handling, tachypnea, tachycardia, nasal flaring)
Signs of circulatory insufficiency: tachypnea, tachycardia, cold peripheries, pale or mottled skin, delayed capillary refill; low BP is a late sign.
Continue fluid resuscitation, reassess and repeat
Intraop MonitoringStandard ASA Monitoring (EKG,BP, SaO2, ETCO2, Temp)
If the neonate is able to maintain respiratory homeostasis and whose hernia size is < 4cm
Invasive Pressure Monitoring
If the neonate is unstable, hypotensive, hypoxic, using accessory muscle to maintain saturation, and with hernia size > 4cm
Central venous line, arterial line
Anesthetic TechniqueSusceptible to aspiration
Awake intubation or RSI
RSI with Propofol; +/- muscle relaxant
Mask induction with Sevoflurane & oxygen
Preemie: 2.5 ETT Term: 3.0-3.5 ETT
A slight leak pressure of 20-25 cmH2O to prevent compression damage to the tracheal mucosa
Bradycardia b/c PNS is dominant
Maintenance of AnesthesiaAnesthesia requirement for maintenance in neonates
(Sevo 2.1%) is less than infants (3.2%)
Oxygen, air, and Sevoflurane
Maintain O2 saturation mid-90’s% to avoid the risk for retinopathy of prematurity
No Nitrous oxide
Keep them on muscle relaxant*
Opioids*
Intraop Fluid ManagementMaintenance
Third space losses
Estimated blood volume
Maximum allowable blood loss
How to give blood and albumin
Maintenance FluidD5 0.2%NS
Via syringe pump or 250ml bag on IV pump or buratrol drip chamber tubing
No air bubbles
May double the MIVF
0-10kg 4-8ml/kg/hr11-20kg 2ml/kg/hr>20kg 1ml/kg/hr
3rd Space LossesLR is used
Albumin 5% maybe used if rapid volume expansion is needed
6-10-15 ml/kg/hr
Estimated Blood Volume
Preterm 100ml/kgFull term 90ml/kg
Allowable Blood Lost
ABL = EBV x (starting Hct – allowable Hct)
starting Hct
How to Give Blood and Albumin
Warm blood with hotline
Use a pediatric blood set + stopcock
Push blood with a syringe for accurate measurement
Give 10-20ml/kg at a time
Watch BP!!!
Surgical RepairGoal: to return the bowel to the abdomen and close the
fascia in one operation
Primary closure
Staged closure: silo pouch first complete closure
Gastroschisis.net
Hemodynamic Effects of Primary Closure
Intra-abdominal Pressure
A NG/OG can be placed in the stomach with a column of saline; or bladder pressure
Goal: < 20 mmHg when closing the defect
Increased intra-abdominal pressure results in:
preload: hypotension
pulmonary compliance: PIP, Vt, ETCO2, SaO2
urine output
Yaster et al
Intragastric pressure > 20 mmHg or CVP > 4mmHg
Higher mortality rate caused by ischemia of the bowel or the lower extremities
Morgan & Mikhail
Suggested criteria for a staged closure include:
1. Intragastric pressure >20 mmHg
2. PIP > 35 cmH2O
3. ETCO2 > 50mmHg
EmergenceIf the neonate tolerated the primary closure or the
defect is very small, may try extubate at the end of the surgery.
In these patients, give reversal and extubate when fully awake, with regular spontaneous breathing, grimacing, moving all limbs vigorously
However, the majority of babies will returned to NICU intubated b/c the increased intra-abd pressure with compromised respiratory function
The Sux DartIf laryngospasm does occur post extubation,
remember to give atropine and succinycholine together
If IV access is not present, atropine and succinycholine can be given IM or sublingually
Atropine 0.02mg/kg IM
Succ 4mg/kg IM
Postop ManagementNeonatal ICU
If remains intubated, continue sedation with morphine (10-20 mcq/kg/hr)
Some may require muscle relaxation for 24 hrs; cisatracurium (3 mcq/kg/min)
The duration of sedation and paralysis is governed by the ease and speed of return of bowel to the abdominal cavity ~ 10 days
#1 Postop ComplicationAbdominal Compartment Syndrome
Upward shift in the diaphragm interfering with ventilation
Renal and hepatic perfusion
Perfusion to lower limbs, ✓ SaO2 on big toes
Re-open the abdomen and place the silo pouch
Reduce the tension on the pouch and allow a portion of the bowel to re-herniate
Other Postop ComplicationsGI Non-GI
Necrotizing enterocolitis Sepsis
Renal insufficiency Ventilator-acquired Pneumonia
Cellulitis of the abd wall UTI
Abd wall breakdown Wound infection
Gastroesophageal reflux
Cholestasis
PrognosisIn the 1960’s, up to 70% of these neonates failed to
survive
With improved preoperative and postop resuscitation, 90% survival rate
Majority of the neonates have no associated cardiac or respiratory abnormalities, survive to normal adult lives
SummaryNeonates with gastroschisis require emergent surgical
repair
Susceptible to heat/fluid loss, infection, electrolyte imbalance, and trauma
Goals: secure the airway, obtain I.V. access, begin fluid resuscitation as early as possible, prevent hypothermia, continue ventilatory support intraop and postop
Questions?
Reference Cauchi, J., Parikh, D. H., Samuel, M., & Gornall, P. (2006). Does
gastroschisis reduction require general anesthesia? A comparative analysis. Journal of Pediatric Surgery, 41, 1294-1297
Hartley, L., & Poddar, R. (2009). Exomphalos and gastroschisis. Continuing Education in Anaesthesia, Critical Care & Pain. doi: 10.1093/bjaceaccp/mkp001
Jaffe RA, Samuels SL. (2004). Anesthesiologist’s Manual of Surgical Procedures. 3rd ed. Philadelphia PA: Lippincott Williams & Wilkins
Leabetter, D. (2006). Gastroschisis and omphalocele. Surgical Clinics of North America, 86, 249-260
Reference Macksey, L. F. (2009). Pediatric Anesthetics and Emergency Drug
Guide. Sudbury, Massachusetts: Jones and Bartlett Publishers
Morgan, G. E., Mikhail, M. S., & Murray, M. J. (2006). Clinical Anesthesiology. 4th ed. New York, NY: McGraw-Hill
Myo, C.C. (2007). Preanesthetic assessment of the newborn with an abdominal wall defect. Retrieved from http://www.amcresidents.com
Wielar, A. (2011). Anesthetic Considerstions for Patients Smaller Than a Box. [PowerPoint slides]. Retrieved from Duke University Advanced Principles of Anesthesia II Blackboard: http://blackboard.duke.edu
Reference Wouters, K., & Walker, I. (2007). Anaesthesia for neonates with
abdominal wall defects. Retrieved from: http://www.frca.co.uk/article.aspx?articleid=100983