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