12-phase flow (12)

1. 1FRAME
   Frame the suspected malrotation-volvulus presentation: age band (neonate < 1 mo most common 50-60 % / infant 1-12 mo / older child 1-12 y / adolescent / adult); vomiting pattern (bilious cardinal alarm vs non-bilious); duration of symptoms (> 6-8 h raises necrosis risk); hemodynamic status (stable vs dehydrated vs shock); associated syndromes (heterotaxy / CDH / omphalocele / gastroschisis / trisomy 21 / duodenal atresia coexistence).
   inputs: age_in_weeks_or_days_at_presentation, pattern_of_vomiting_bilious_vs_non_bilious, duration_of_bilious_emesis_in_hours, heterotaxy_syndrome_or_cdh_or_omphalocele_or_gastroschisis_history
   advance: Age + vomiting pattern + duration + syndrome history tagged; pretest probability + emergency-tier framing set
2. 2ENTRY
   Recognise via cardinal clinical sign (bilious vomiting in infant — malrotation-volvulus until proven otherwise) OR pathognomonic imaging (whirlpool sign on US; ligament of Treitz right of midline on UGI; corkscrew duodenum on UGI) OR peritonitis with bilious emesis (late finding indicating ischemic / necrotic bowel) OR atypical older-child intermittent presentation.
   inputs: pattern_of_vomiting_bilious_vs_non_bilious, peritonitis_signs_rigidity_rebound_guarding
   advance: Malrotation-volvulus suspected by clinical sign, imaging signature, or peritonitis pattern
3. 3CONTEXT
   Age + sex + weight + gestational age + vitals + duration of symptoms + vomiting pattern + abdominal distention + lethargy + heterotaxy / CDH / omphalocele / gastroschisis history + trisomy 21 + duodenal atresia + prior abdominal surgery / known malrotation.
   inputs: age_in_weeks_or_days_at_presentation, sex_at_birth, weight_kg, gestational_age_at_birth_term_vs_preterm, hr_pediatric, temperature_pediatric, duration_of_bilious_emesis_in_hours, pattern_of_vomiting_bilious_vs_non_bilious, abdominal_distention_present, lethargy_or_poor_feeding, heterotaxy_syndrome_or_cdh_or_omphalocele_or_gastroschisis_history
   advance: Demographic + risk-factor + clinical context + syndrome-association documented
4. 4RED_FLAGS
   Hemodynamic instability (hypotension by age, capillary refill > 3 s, mottling) + bilious emesis → emergent OR; do NOT delay for imaging; resuscitation in parallel. Peritonitis (rigidity, rebound, guarding) + bilious emesis → emergent ex-lap within < 2 h. Lactate > 2 mmol/L in infant with bilious emesis → ischemic bowel concern (LR+ 5-10). Hematochezia / melena → late ominous finding from mucosal sloughing. Duration > 6-8 h → higher necrosis rates. Neonate with bilious emesis within first 24 h of life → emergent UGI + STAT surgery.
   inputs: sbp_pediatric, capillary_refill_pediatric, peritonitis_signs_rigidity_rebound_guarding, duration_of_bilious_emesis_in_hours, hematochezia_or_melena
   advance: Emergency-tier red flags evaluated; OR triggered if unstable / peritonitis; resuscitation initiated
5. 5INITIAL_WORKUP
   IV access + NPO + NG decompression (reduces aspiration risk pre-anesthesia; pediatric anesthesia society); CBC + CMP with lactate + glucose + coagulation + type-and-screen; STAT upper GI contrast series (gold standard; ligament of Treitz position + duodenal C-loop + corkscrew + beak); abdominal US with whirlpool assessment concurrent if experienced center; pediatric surgery consult triggered IMMEDIATELY on bilious-emesis presentation (do NOT wait for imaging if clinical suspicion high).
   inputs: cbc_with_diff_pediatric, cmp_with_chloride_potassium_bicarbonate_and_lactate, type_and_screen_or_crossmatch_pediatric, coagulation_panel_pt_inr_aptt, glucose_pediatric, upper_gi_contrast_series_gold_standard
   actions: panel.cbc, panel.renal, panel.coag
   advance: IV access + NPO + NG + labs + UGI obtained; pediatric surgery consult engaged
6. 6BRANCHING_WORKUP
   Source-directed: bedside US with whirlpool assessment if UGI series delayed or non-diagnostic AND clinical suspicion remains high; KUB for free air (perforation) or paucity of distal gas pattern; CT abdomen / pelvis in older children / adults primarily (avoid in neonates / infants when US + UGI available); blood cultures if febrile / septic features; lactate trending for ischemic bowel monitoring.
   inputs: abdominal_us_with_whirlpool_assessment, kub_xray_for_obstruction_pattern_and_free_air, ct_abdomen_pelvis_with_contrast_older_children, blood_cultures_if_febrile_or_septic
   advance: Diagnostic pathway closed: malrotation-volvulus confirmed (UGI / US / CT positive) OR alternative diagnosis pursued OR direct-to-OR for strong suspicion + unstable
7. 7DIFFERENTIAL
   Bilious emesis differential in infant: malrotation-volvulus (cardinal; emergent UGI + surgery) / duodenal atresia (bilious emesis in first 24-48 h of life; double-bubble + no distal gas on KUB; coexistent malrotation in ~ 30 %) / intestinal atresia (bilious emesis + distal-bowel obstruction pattern) / NEC (preterm neonate; pneumatosis intestinalis on KUB — `peds.nec.v1`) / sepsis with ileus (febrile, lethargic; routes to id.neonatal-sepsis.early-late.v1 or id.sepsis.peds.v1) / incarcerated inguinal hernia (palpable groin mass + irreducible) / intussusception (different age band 6 mo - 3 y typically non-bilious initially; `peds.intussusception.v1`). Non-bilious differential: pyloric stenosis (non-bilious projectile in 2-8 wk infant; `peds.pyloric-stenosis.v1`) / GER / formula intolerance. Older-child differential: chronic abdominal pain ddx (functional, IBS-like, intermittent malrotation, abdominal migraine, gastroparesis).
   advance: Mimics excluded by UGI / US / KUB / clinical features; malrotation-volvulus diagnosis confirmed or alternative pathway entered
8. 8RISK_STRATIFICATION
   Tier 1 (life-threatening — unstable bilious emesis or peritonitis or extensive necrosis): emergent OR within < 2 h; PICU post-op. Tier 2 (life-threatening — stable bilious emesis in infant with positive imaging): urgent OR within < 6 h; inpatient ward or PICU post-op based on operative findings. Tier 3 (severe — older child with intermittent presentation + positive UGI): urgent vs elective OR timing based on symptom acuity; laparoscopic Ladd appropriate if stable. Tier 4 (severe — incidentally diagnosed asymptomatic malrotation): elective laparoscopic Ladd; counsel on prophylactic risks / benefits. Tier 5 (severe — failed Ladd with extensive necrosis / short bowel): staged closure + TPN + intestinal rehabilitation + transplant evaluation. Syndromic tier (heterotaxy / CDH / omphalocele / gastroschisis): intra-operative evaluation + Ladd at time of corrective procedure or staged per APSA heterotaxy consensus.
   inputs: sbp_pediatric, peritonitis_signs_rigidity_rebound_guarding, duration_of_bilious_emesis_in_hours, cmp_with_chloride_potassium_bicarbonate_and_lactate
   advance: Tier assigned + OR timing chosen + admit-vs-PICU decision documented
9. 9TREATMENT
   Resuscitation in parallel with imaging / OR mobilization: NS or LR 20 mL/kg IV bolus over 30-60 min if dehydration / shock; repeat × 1-2 PRN (max ~ 60 mL/kg cumulative before reassessing for fluid overload); maintenance D5 1/2NS with electrolytes after first void. NG decompression to reduce aspiration risk pre-induction (pediatric anesthesia society). Pre-op single-dose cefazolin 25-30 mg/kg IV at induction for elective stable Ladd (Cantey SCOUT 2016 stewardship); broad-spectrum pip-tazo 80-100 mg/kg IV q6-8h × 5-7 d for confirmed bowel ischemia + perforation / peritonitis (Solomkin IDSA 2010 peds-adapted PMID 20583865); 7-14 d if uncontrolled source; meropenem 20 mg/kg IV q8h alternative for severe / hospital-acquired. Cefotaxime + metronidazole alternative if < 28 d (avoid ceftriaxone — bilirubin displacement; AAP Puopolo 2018). RSI for full stomach + aspiration risk (pediatric anesthesia society). Open laparotomy preferred for acute volvulus + suspected ischemia (exposure + viability + easier resection); laparoscopic appropriate for stable elective (incidentally diagnosed or older child intermittent). Ladd procedure: reduce volvulus (counterclockwise detorsion ~ 270 degrees+) + divide Ladd bands + widen mesenteric base + cecum to LLQ + appendectomy. Second-look operation at 24-48 h for borderline bowel viability — preserve maximum bowel length to avoid short bowel syndrome (APSA + pediatric GI consensus). Vasoactive support epinephrine 0.05-0.3 mcg/kg/min or norepinephrine 0.05-0.5 mcg/kg/min for refractory shock (SSC peds 2020).
   inputs: weight_kg, cmp_with_chloride_potassium_bicarbonate_and_lactate, upper_gi_contrast_series_gold_standard
   actions: panel.renal
   advance: Resuscitation complete + antibiotics given + RSI + NG decompression + Ladd procedure performed (laparoscopic for stable elective; open for acute volvulus / ischemia)
10. 10DISPOSITION
    Post-laparoscopic Ladd (stable elective) → inpatient ward 2-5 d LOS for feed advance + monitoring. Post-open Ladd (acute volvulus with viable bowel) → inpatient ward or PICU 5-10 d LOS based on extent + comorbidities. Post-open Ladd with resection → PICU 10-21 d+ LOS; intestinal rehabilitation enrollment if extensive resection. Second-look operation at 24-48 h if borderline viability. PICU for: extensive necrosis post-op / sepsis / hemodynamic instability / short bowel syndrome / preterm with comorbidity.
    inputs: sbp_pediatric, cmp_with_chloride_potassium_bicarbonate_and_lactate
    advance: Disposition + level of care set; post-op monitoring + second-look plan in place
11. 11MONITORING
    Post-op vitals q1-2h × first 6 h then q4h; serial abdominal exams q4h; serial lactate + CBC + CMP q6-8h × first 24-48 h then q12-24h; wound inspection daily; NG output + character; feed advance from clear liquids → formula / breast milk as tolerated post-bowel-function return (typically 3-7 d post-Ladd; longer for resection); strict I/O; serial weights daily; capnography post-extubation in very young or comorbid (pediatric anesthesia society). Second-look operation at 24-48 h if borderline viability — preserve maximum bowel length. Antibiotic course tracking (5-7 d for source-controlled; 7-14 d if uncontrolled source). Short bowel monitoring: stool / ostomy output volume, electrolyte balance, growth trajectory, TPN tolerance, line-source infection surveillance.
    inputs: pattern_of_vomiting_bilious_vs_non_bilious, cmp_with_chloride_potassium_bicarbonate_and_lactate
    advance: Recovery progressing; feeds advanced; bowel function returned; antibiotic course complete; discharge criteria approaching
12. 12FOLLOWUP
    Post-op pediatric surgical follow-up at 2-4 weeks for wound check + scar inspection + weight-gain review; pediatrician follow-up within 1-2 weeks for routine well-baby / well-child care including weight-gain trajectory + feeding tolerance; pediatric GI consult at 4-6 weeks for short bowel syndrome management if applicable (TPN tolerance, enteral advance, line-source surveillance, glucagon-like peptide-2 analog teduglutide consideration in select); intestinal transplant program referral for irreversible TPN dependence + life-threatening complications (APSA + pediatric GI / transplant consensus); recurrence surveillance for the ~ 2-5 % post-Ladd recurrence rate (return precautions taught + low threshold for repeat UGI on recurrent symptoms). Heterotaxy / CDH / omphalocele / gastroschisis patients — ongoing multidisciplinary follow-up for index syndrome.
    advance: Follow-up scheduled + return precautions delivered + family education complete + short bowel program enrolled if applicable + recurrence surveillance plan in place