The document outlines pediatric surgical management related to fluids, electrolytes, and several conditions including hypertrophic pyloric stenosis, intussusception, malrotation, gastroschisis, omphalocele, Hirschsprung's disease, umbilical and inguinal hernias, and cryptorchidism. Each condition details symptoms, examinations, diagnostic imaging, and treatments, emphasizing fluid resuscitation, surgical interventions, and specific management approaches tailored to pediatric patients. Key topics include differences in fluid maintenance and electrolyte handling between children and adults, as well as surgical techniques suitable for various congenital and acquired conditions.

1. Pediatric Surgery

2. Fluids & Electrolytes
• Maintenance rate: 4/2/1 cc/kg/hr
• GFR ~21 cc/min/1.73 m2 vs 70 mL/min/1.73 m2 in an adult​
• Urine concentration ~600 mOsm/kg vs ~1200 mOsm/kg​
• Trauma: crystalloid 20 cc/kg bolus x2, if no response pRBC 10 cc/kg bolus
• Adequate UOP: <2 yoa = 2-3 cc/kg/hr, >2 yoa = 1 cc/kg/hr
• Acidosis correction for pH < 7.25:
• Base deficit x weight (kg) x (0.5 in newborns OR 0.4 in small OR 0.3 in older children)
• Dilute to 0.5 mEq/mL d/t hyperosmolarity
• Give ½ as bolus and remaining half slowly
• Adequate UOP: <2 yoa = 2-3 cc/kg/hr, >2 yoa = 1 cc/kg/hr

3. Hypertrophic Pyloric Stenosis
• Sx: projectile non-bilious emesis after feeds
• Exam: olive like mass in RUQ
• Labs: hypochloremic, hypokalemic, metabolic
alkalosis
• Imaging: US of pylorus >16 mm long, >4 mm
thick
• Tx: fluid resuscitation (NS  D5NS w/ 10 mEq
K), electrolyte optimization, Ramstedt
pyloromyotomy (split layers until submucosa
bulges out)

4. Intussusception
• Sx: abdominal pain, vomiting
• Exam: currant jelly stools (vascular
congestion), sausage mass, distention
• Etiology: bowel invagination (MC ileum into R
colon) d/t lead points: Peyer’s patch,
lymphoma, Meckel’s
• Tx: air contrast enema (80%), max 120 mm
Hg, column height 1 meter; OR if unable to
reduce, peritonitis, pneumopertioneum

5. Malrotation
• Sx: sudden onset bilious emesis (90% by 1
yoa)
• Exam: distention, abdominal pain
• Etiology: no 270 deg CC rotation, c/f bowel
ischemia
• Imaging: UGI (duo doesn’t cross midline)
• Tx: resect Ladd’s bands, CC rotation w/ cecum
LLQ, duo RUQ, appendectomy

6. Gastroschisis
• Sx: intestines through R of umbilicus defect
• Exam: no peritoneal sac, stiff bowel,
associated w/ intestinal atresia
• Tx: saline soaked gauze, resuscitate, TPN,
NPO, repair when stable (silastic mesh silo),
primary closure later if silo (watch ACS)

7. Omphalocele
• Exam: bowel through midline w/ peritoneal
sac
• Etiology: failure of embryonal development;
associated w/ malro & Down syndrome
• Cantrell Pentalogy: cardiac, pericardium,
sternal, diaphragmatic, omphalocele
• Tx: saline soaked gauze, resuscitate, TPN,
NPO, primary vs mesh repair vs 2-3 month
epithelialization then repair

8. Hirschsprung’s disease
• Sx: failure to pass meconium in 24 hrs,
distention, stool explosion w/ rectal exam
• Etiology: failed neural crest migration l/t loss
of ganglion cells in myenteric plexus
• Imaging: AXR prox dilated colon
• Dx: full thickness rectal biopsy
• Tx: likely initial colostomy w/ subsequent
Soave vs Duhamel

9. Umbilical hernia
• Sx: midline bulge
• Etiology: failure of closure of linea alba (most
close by age 3), increased risk in AAs &
prematures
• Tx: surgery at 5 yoa, incarceration, VP shunt

10. Inguinal hernia
• Sx: groin bulge (R 60%, L 30%, BL 10%)
• Etiology: persistent processus vaginalis
(hernia sac extends into internal ring); M > F
• Tx: elective repair w/ high ligation of hernia
sac (24 hrs after reduction); emergent repair
if unable to reduce; consider b/l exploration

11. Cryptorchidism
• Sx: groin bulge
• Imaging: MRI if unable to palpate
• Labs: chromosomal studies if bilateral
• Tx: wait 6 months; orchiopexy through
inguinal incision; if unable to get testes down,
wait 6m and try again, if fails, ligate spermatic
vessels (vas deferens blood supply will
collateralize)
• Cancer risk stays same (seminoma)