Perioperative Evaluation And Treatment In Pediatrics

Perioperative Management of the Pediatric Patient Moises Auron MD, FAAP FACP Assistant Professor of Medicine Hospital Medicine

10/15/09

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Disclosure Statement • The author has no relevant financial interest or other relationship with the manufacturer(s) of any commercial product(s) and/or provider(s) of commercial services that are discussed in this educational activity.

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Outline • • • • • • • • • • • • •

Goals of pre-operative assessment Anesthesia associated risk General pre-operative management Pulmonary issues Cardiac issues Brief review of cardiac risk assessment and management in noncardiac surgery – adult guidelines Morbid obesity Neurologic issues and Epilepsy Musculoskeletal and craniofacial issues SCD Perioperative Management of Diabetes Perioperative VTE Prophylaxis Psychological preparation for surgery

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Goal of preoperative assessment • Detection of unrecognized conditions that increase the risk of surgery. • Optimize the patient’s current medical problems and anticipate potential complications. – Anticipate pulmonary edema post-T/A – OSA – Monitor for atlantoaxial instability (Down’s) 10/15/09

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Model of Plane Flight

PATIENT Surgeon = Pilot

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Anesthesia = Co-Pilot

Michota F. Jaffer A. CCJM. 2006

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Anesth Analg 2004;99:1058-69.

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What is different in Pediatrics • Age - > 70 y/o – robust indicator for postoperative pulmonary morbidity • Exercise capacity – unclear in infants and toddlers – Climb 1 flight of stairs = 4 mets = low CV risk

• Medication use • Risk for venous thromboembolism 10/15/09

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General perioperative concerns in Pediatrics. • Congenital heart disease – Hypoxia, arrhythmias, and cardiovascular instability paradoxical air emboli

• Prematurity – Postoperative apnea

• Gastrointestinal reflux – Aspiration pneumonia

• URI – Laryngospasm, bronchospasm, hypoxia, and pneumonia

• Craniofacial abnormality – Difficult airway 10/15/09

Childs Nerv Syst (2006) 22:834–843

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Patient related risk

Procedure related risk

Perioperative risk

Anesthetic-related risk

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Provider-related risk

Michota F, Frost S; Med Clin N Am 2002.

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Role of the surgeon • Surgeons are typically consulted for evaluation and treatment of: – healthy child who is undergoing elective surgery – the chronically ill child who requires surgery – the acutely ill on injured child who requires emergent surgery.

Pediatrics 1996;98;502-508. 10/15/09

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Role of the anesthesiologist • Anesthesia may begin outside the OR with the administration of preoperative medication. • Patient follow up until D/C from the PACU – Except if regional analgesia or spinal block are used

Pediatrics 1996;98;502-508. 10/15/09

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Anesthesia-associated risk • Risk for adverse events continues to be higher in infants and young children • Overall mortality rate was 0.9/10,000 anesthetics • Incidence of cardiac arrest of 1.7/10,000 – Adult (1.4/10,000). – Children < 12 y/o (4.7/10,000) – 3x – Complications of airway management (laryngospasm, difficult intubation, and pulmonary aspiration of gastric contents) – Halothane (hypotension, arrhythmia, or both). 10/15/09

Maxwell LG. Anesthesiology Clin N Am. 2004;22:27-43.

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Anesthesia-associated risk • Greater risk occurs in infants < 4 wk old. – More likely to be having major surgery (intrathoracic or intraabdominal) – Have more serious underlying disease – Increased percentage are (ASA) physical status 3–5. – Reduction in respiratory-related events compared with previous studies was believed to be because of improved detection of impending respiratory events caused by oximetry and capnography. – Associated with emergency surgery, halothane or sevoflurane, caudal injection of bupivacaine/epinephrine 10/15/09

Maxwell LG. Anesthesiology Clin N Am. 2004;22:27-43

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ASA Classification • Class 1 A normally healthy patient • Class 2 A patient with mild systemic disease • Class 3 A patient with severe systemic disease that is not incapacitating • Class 4 A patient with an incapacitating systemic disease that is a constant threat to life • Class 5 A moribund patient who is not expected to survive for 24 h with or without operation 10/15/09

Anesthesiology 1963; 24: 111. Pediatric Anesthesia 2007 17: 216–222.

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ASA Classification in Pediatrics

Pediatric Anesthesia 2007 17: 216–222. 10/15/09

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Preoperative Evaluation • HPI • PMH – Croup – OSA – Cervical instability (Down’s)

• Medications – NSAID’s • Allergies – Latex (spina bifida) Pediatrics 1996;98;502-508. 10/15/09

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Pre-operative evaluation • Family history – Anesthetic-related complications • malignant hyperthermia • prolonged paralysis after anesthesia (pseudocholinesterase deficiency)

– Bleeding disorders – Muscular dystrophy – Drug use (aminoglycosides) Pediatrics 1996;98;502-508. 10/15/09

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Pre-operative evaluation • Last meal intake • Physical examination – Hydration status

Pediatrics 1996;98;502-508. 10/15/09

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Ancillary testing • Hb - when significant anemia (<9 g/L) is suspected – (eg, infants, growing premature infants, and patients with chronic illnesses) – to establish a reference point in anticipation to significant blood loss (Orthopedic surgery).

• Pregnancy testing Pediatrics 1996;98;502-508. 10/15/09

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Ancillary testing •

Coagulation profile – history or medical condition suggests a possible hemostatic defect: • • • • • •

large bruises and hematomas simultaneous bruising on several parts of the body Hematochezia frequent and prolonged epistaxis Hemarthrosis unusual bleeding after minor trauma (including dental extraction)

– Recent ingestion of aspirin or NSAIDS. – Cardiopulmonary bypass – induction of hemostatic disorder by platelet activation and consumption – Tonsillectomy; airway surgery – Neurosurgical patients (craniotomy)

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Minor surgery and a negative history: no tests are suggested. Pediatrics 1996;98;502-508.

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Fasting guidelines • • • • •

8-6-4-2 8 hours solids 6 hours formula 4 hours breast milk 2 hours clear liquids Anesthesiology. 1999;90(3):896-905 Acta Anaesthesiol Scand 2005;49:1041-1047.

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Best Practice & Research Clinical Anaesthesiology. 2006; 20(3):47181.

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Pulmonary issues • URI – defer surgery until symptoms resolve – Increased risk of bronchospasm – Decreased 50% with use of Laryngeal Mask Airway

• Asthma – should be optimally controlled – Continue bronchodilators and oral meds in AM of surgery – Delay surgery 6 wk after asthma attack (FEV1 remains low x 6 wk). – Prednisone 1 mg/kg 24-48 h pre-operatively and in the AM of surgery. 10/15/09

Maxwell LG. Anesthesiology Clin N Am. 2004;22:27-43 Pediatrics 1996;98;502-508.

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Pulmonary issues • FEV1/FVC -useful predictors of the need for postoperative mechanical ventilation among patients at risk (eg, cystic fibrosis, severe scoliosis, or kyphoscoliosis). • Adults - increased incidence of need for postoperative mechanical ventilation: – FEV1/FVC < 50% – FEV1 < 35% predicted – Absolute FVC < 25 mL/kg 10/15/09

Maxwell LG. Anesthesiology Clin N Am. 2004;22:27-43

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Pulmonary issues • Cystic fibrosis – continue pulmonary toilet, optimize nutritional status, continue home meds (inhaled and systemic antibiotics, dornase alpha, acetylcysteine, bronchodilators).

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Maxwell LG. Anesthesiology Clin N Am. 2004;22:27-43

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Pulmonary issues • Obstructive Sleep apnea – Adenotonsillar hyperthrophy, obesity, Prader Willi, Down’s – Pulmonary HTN and Cor Pulmonale – Greatest risk of post-op upper airway obstruction • • • •

Tissue edema Secretions Sedation (narcotics) Pulmonary edema

– Best practice: 24 h observation in PICU 10/15/09

Maxwell LG. Anesthesiology Clin N Am. 2004;22:27-43

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Pulmonary issues • Prematurity and apnea – Decreased risk with spinal anesthesia – Preoperative use of caffeine – Admit and monitor with SpO2.

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Maxwell LG. Anesthesiology Clin N Am. 2004;22:27-43

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Former Preterm  Risk for Postoperative apnea • • • • •

Bronchopulmonary dysplasia Chronic hypoxemia and hypercarbia Tracheomalacia; bronchomalacia Pulmonary hypertension; Cor pulmonale Risk factors: – Anemia (Hct <30%) – Apnea at home – Gestational age (<30 wk) – LBW (< 1.5 kg) – Lower weight at time of surgery – Complicated NICU course

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Murphy JJ. J Pediatr Surg. 2008. May;43(5):865-8

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Post-operative atelectasis • • • •

Impaired surfactant Increased gas reabsorption Extrinsic compression Favored by: • General anesthesia • Recumbent position – decrease FRC 0.5 – 1.0 L • High FiO2 • Surgery close to the diaphragm

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Anesthesiology 2005; 102:838–54 Curr Opin Anaesthesiol. 2007;20:37–42.

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Post-operative atelectasis

Anesthesiology 2005; 102:838–54 10/15/09

Curr Opin Anaesthesiol. 2007;20:37–42.

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Age and atelectasis • Children age 1–3 years  atelectasis develop more readily than in adults. • Increased thoracic rib cage compliance  less outward recoil of the chest wall  less distending force on the lung. • High closing volume (the lung volume at which small airways begin to close) Anesthesiology 2005; 102:838–54 10/15/09

Curr Opin Anaesthesiol. 2007;20:37–42.

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Physiologic consequences of atelectasis • • • •

Decreased compliance Hypoxemia Increased pulmonary vascular resistance Lung injury (repetitive opening and closure of small airways).

Anesthesiology 2005; 102:838–54 10/15/09

Curr Opin Anaesthesiol. 2007;20:37–42.

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N = 100 postop cardiac surgery patients

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Chest 1995; 107:81-84

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Tonsillectomy: special considerations • Risk for post-operative obstructive apnea • Risk for post-obstructive pulmonary edema • Increased risk of bleeding – use of postoperative NSAIDS is controversial as it is associated with increased re-operation.

Anesth Analg 2003;96:68 –77. 10/15/09

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Child with cardiac murmur • • • •

Innocent murmur Pathologic murmur New Endocarditis prophylaxis guidelines Cardiology evaluation and f/u for a child with complex congenital heart disease.

Pediatrics 1996;98;502-508. Current Opinion in Anaesthesiology 2007, 20:216–220 10/15/09

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Hypoplastic Left Heart Syndrome and Non-cardiac surgery

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J Pediatr Surg. 2002;37:1399-1403.

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Prophylaxis against bacterial endocarditis CLASS IIa • Prophylaxis against infective endocarditis is reasonable for the following patients at highest risk for adverse outcomes from infective endocarditis who undergo dental procedures that involve manipulation of either gingival tissue or the periapical region of teeth or perforation of the oral mucosa: • Patients with prosthetic cardiac valves or prosthetic material used for cardiac valve repair. (Level of Evidence: B) • Patients with previous infective endocarditis. (Level of Evidence: B) • Patients with CHD. (Level of Evidence: B) Circulation. 2008;118:887-896. 10/15/09

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Prophylaxis against bacterial endocarditis CLASS IIa • Unrepaired cyanotic CHD, including palliative shunts and conduits. (Level of Evidence: B) • Completely repaired congenital heart defect repaired with prosthetic material or device, whether placed by surgery or by catheter intervention, during the first 6 months after the procedure. (Level of Evidence: B) • Repaired CHD with residual defects at the site or adjacent to the site of a prosthetic patch or • prosthetic device (both of which inhibit endothelialization). (Level of Evidence: B) • Cardiac transplant recipients with valve regurgitation due to a structurally abnormal valve. (Level of Evidence: C) Circulation. 2008;118:887-896. 10/15/09

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Prophylaxis against bacterial endocarditis CLASS III • Prophylaxis against infective endocarditis is not recommended for nondental procedures: – transesophageal echocardiogram, EGD, or colonoscopy) in the absence of active infection. (Level of Evidence: B) Circulation. 2008;118:887-896. 10/15/09

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Antibiotic dose for BE prophylaxis SINGLE DOSE 30-60 MIN BEFORE • Amoxicillin p.o. 50 mg/kg • Ampicillin 50 mg/kg IM/IV or Cefazolin or ceftriaxone 50 mg/kg IM/IV • Allergic to penicillins: – Cephalexin p.o. 50 mg/kg – Clindamycin 20 mg/kg – Azithromycin or clarithromycin 15 mg/kg – Cefazolin or ceftriaxone - 50 mg/kg IM/IV – Clindamycin 20 mg/kg IM or IV Circulation. 2008;118:887-896. 10/15/09

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Morbid Obese patient • • • •

Overweight: BMI > 85%le Obesity: BMI of more than 95%le Superobesity: BMI > 99 %le Adolescent/Adult: BMI > 40 kg/m2

Current Opinion in Anaesthesiology 2008;21:308–312. 10/15/09

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Morbid obesity: medical etiology • Prader–Willi syndrome • Laurence–Moon–Biedl syndrome • Hypercaloric diet (glycogen storage diseases) • Steroid induced (Hem-Onc, nephrotic syndrome) • Poor mobility (late stage Duchenne’s) Current Opinion in Anaesthesiology 2008;21:308–312. 10/15/09

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Prader Willi Syndrome

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Pediatric Anesthesia 2006 16: 712–722

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Morbid obesity: perioperative considerations • • • • •

Hypertension and LVH Obstructive sleep apnea / hypoventilation Diabetes / insulin resistance GERD NAFLD / NASH

Current Opinion in Anaesthesiology 2008;21:308–312. 10/15/09

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Morbid obesity: Pediatric perioperative considerations • • • • •

Slipped capital femoral epiphysis Blount’s disease Cholelithiasis Polycystic ovary syndrome Idiopathic intracranial hypertension (pseudotumour cerebri) Current Opinion in Anaesthesiology 2008;21:308–312.

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Morbid obesity: Pre-operative examination in children •

• • • • • •

History: – symptoms of sleep apnea – tolerance to exercise: breathlessness, asthma; – recent weight loss or gain – medications, including OTC herbs or special mixtures taken to lose weight which can interfere with anaesthesia or haemostasis. • e.g. garlic, ginger, etc. Document BMI in percentile chart. Pulse-oximetry (SpO2) on room air / Nocturnal SpO2 Fasting blood glucose Echocardiography (Hypertensive patient) Preoperative fasting – similar rules as the nonobese population. GERD: usual anti-reflux therapy should be administered. Current Opinion in Anaesthesiology 2008;21:308–312.

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Elective surgery in morbid obesity: 2009 AHA guidelines

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Circulation. 2009;120:86-95.

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Neural tube defects • Assessment for coexistent congenital anomalies • 90% require CSF diversion • Subsequent surgeries: – Infection – Malfunction – Outgrowing the shunt hardware

• Associated urogenital and musculoskeletal dysfunction – UTI/VUR/hydronephrosis  renal function evaluation – Scoliosis  respiratory function evaluation – Lower-extremity abnormalities

• Latex allergy Pediatrics 1996;98;502-508. 10/15/09

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Neuromuscular disorders • Inhalational agents: cerebral vasodilation  increase ICP • Ensure patency and proper functioning of CSF shunt • Immediate postop period  Impaired airway reflexes – Document pre-operatively any evidence of brainstem dysfunction (eg, vocal cord paralysis, swallowing dysfunction, or aspiration)

• Increased risk for postoperative weakness  postoperative respiratory care and prolonged mechanical ventilation / PP. • Succinylcholine  Hyperkalemia; malignant hyperthermia

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Maxwell LG. Anesthesiology Clin N Am. 2004;22:27-43

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Epilepsy • Record type and frequency of seizures • Continue antiepileptic medications on the AM of surgery • Uncontrolled seizures  Neurology evaluation. • Check serum levels of anticonvulsant • Most anticonvulsants have long half-lives, and the omission of one dose does not decrease the blood level significantly. • No need to determine anticonvulsant levels if: – seizure-free for 2 years – no adjustment of their anticonvulsant dose Pediatrics 1996;98;502-508. 10/15/09

Maxwell LG. Anesthesiology Clin N Am. 2004;22:27-43

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Epilepsy: perioperative considerations • Tuberous sclerosis – cardiac rhabodomyomas: obstruction, dysrhythmias – Renal lesions  HTN, CKD

• • • • • •

Traditional antiepileptics: P-450 inducers Topiramate  NAG metabolic acidosis Sodium valproate  platelet abnormalities, bleeding Sodium valproate and Felbamate  liver failure Ketogenic diet  avoid lactated Ringers solution Sevoflurane  Epileptogenic potential Childs Nerv Syst. 2006;22:834–843. J Anesth. 2006;20:135–137.

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Paediatric Anaesthesia 2002;12:700–704.

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Phakomatoses: extra-CNS findings • Linear nevus sebaceous of Jadassohn – Aortic coarctation, PDA, VSD

• Neurofibromatosis – Pheochromocytoma – 5% – Kyphoscoliosis (type 1)

• Sturge Weber – Aortic coarctation

• Von Hippel Lindau – Pheocromocytoma – 10% – RCC – 25% 10/15/09

Paediatric Anaesthesia 2000;10:121–128

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Cervical spine instability • Mucopolysaccharidoses (Hurler’s and Monquio’s syndromes): odontoid hypoplasia • Rheumatoid arthritis: atlantoaxial instability, subaxial instability, and superior migration of the odontoid process. • Down syndrome: 15% asymptomatic atlantoaxial instability • Document pre-operative screening flexionextension Cervical spine Roentgenograms • Consider fiberoptic intubation. Pediatrics 1996;98;502-508. 10/15/09

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Craniosynostosis • Multidisciplinary evaluation by a craniofacial team • Monitor for signs of increased intracranial pressure • Nonsyndromic craniosynostosis are usually otherwise healthy. • Syndromic craniosynostosis can have associated anomalies: – Crouzon’s or Apert’s syndrome can have very abnormal airway anatomy  fiberoptic intubation.

• Identifying a history of OSA • Apert’s syndrome  congenital cardiac defects.

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Am J Med Gen. 2005; 45(6):758 - 760. Anesthesiology Clin. 2007;25:465–481

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Sickle cell patients • Heterozygous sickle cell trait  generally asymptomatic • Active sickling conditions (SS, SC, S-β thalassemia) – reduce risk of complications by preoperative transfusions to reduce the total HbS level < 40%.

• Coordination among the pediatrician, hematologist, anesthesiologist, and surgeon is essential. 10/15/09

Fu T. Pediatr Blood Cancer 2005;45:43–47. Marchant WA. Paediatric Anaesthesia 2003;13:473–489

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Systemic manifestations of SCD

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Fu T. Pediatr Blood Cancer 2005;45:43–47. Marchant WA. Paediatric Anaesthesia 2003;13:473–489

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Perioperative management of SCD • Avoid dehydration – impaired renal concentrating ability. • Deoxygenation – incentive spirometry; SpO2 monitoring • Vascular stasis – maintaining a normal C.O., a normal blood volume, and BP. • Hypothermia – keeping the patient warm • Acidosis – good hydration, warm • Infection – prophylactic antibiotics • Adequate analgesia, to enable effective physiotherapy and early ambulation must be emphasized.

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Regional anesthesia and SCD • Redistribution of blood flow may lead to an increase in capillary and venous oxygen tension in the blocked region • Compensatory vasoconstriction in nonblocked areas leads to a fall in the SvO2. • Lack of control of ventilation, regional hypoperfusion and venous stasis. • Cooperative Study of Sickle Cell Disease (N=3765) – 10 y. – 1079 surgeries (N= 717) – Post-op SCD-related complications (painful crisis, ACS, and CVA) were more frequent in patients who received regional anaesthesia (P=0.058). 10/15/09

Koshy M, et al. Blood 1995; 86: 3676–3684. Marchant WA. Paediatric Anaesthesia 2003;13:473–489

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Transfusion in SCD with General Anesthesia

Conclusions. “Minor or low-risk elective surgical procedures in children with Hb SS may not routinely require pre-operative transfusion” 10/15/09

Fu T. Pediatr Blood Cancer 2005;45:43–47

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Adenotonsillectomy and SCD • Postop. pain, hypoventilation, atelectasis, hypoxia. – Aggressive pulmonary toilet, NIPPV, bronchodilators and incentive spirometry – HbS < 40%. – Preoperative Transfusion in Sickle Cell Disease Study Group (N=118)  no advantage in aggressive transfusion regimen vs. conservative regime. 10/15/09

Marchant WA. Paediatric Anaesthesia 2003;13:473–489 64 Waldron P. J Ped Hematol Onc 1999; 21:129–135.

Cholecystectomy and SCD • Laparoscopic approach is preferred • Avoid emergency surgery – high morbidity

• Conservative pre-operative transfusion – National Preoperative Transfusion Study (N=364) – Aggressive: preop Hb 10 g/dL and HbS< 30% – Conservative: Hb 10 g/dL independent of HbS. • No difference between groups. Marchant WA. Paediatric Anaesthesia. 2003;13:473–489. 10/15/09

Haberkern CM. Blood. 1997;89(5):1533-1542.

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Orthopedic Surgery and SCD • Aseptic necrosis of the hip occurs in up to 50% of patients. • Conservative preoperative transfusion – Hb (9-11 g/dL). • Careful use of tourniquet - stasis, hypoxia and acidosis beneath and distal to the tourniquet cuff  favors red cell sickling. Marchant WA. Paediatric Anaesthesia. 2003;13:473–489 10/15/09

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Neurosurgery and SCD • Keep Hct > 30 and HbS < 30% – Minimize risk of stroke

• Careful use of hypertonic agents – Urea – preferred – Old contrast media

• Careful use of Epsilon-Aminocaproic Acid – Generally used in spinal surgery – Can predispose to vaso-occlusive crises

• Avoid hypothermia 10/15/09

Marchant WA. Paediatric Anaesthesia. 2003;13:473–489

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Cardiac Surgery and SCD • Open-heart surgery with hypothermic cardiopulmonary bypass precipitate sickling. • Preoperative correction of anemia • Pre-operative exchange transfusion – Increase in 2,3-DPG  increase DO2

• Avoidance of hypoxia and acidosis • Avoidance of aortic cross-clamping, hypothermia, cardioplegia and topical cooling 10/15/09

Marchant WA. Paediatric Anaesthesia. 2003;13:473–489

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Patients on chronic steroids • Perioperative stress dose of steroids • Prednisone p.o. 2.5–5 mg/m2 BSA the night before • Hydrocortisone 50 mg/m2 before anesthetic induction

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Maxwell LG. Anesthesiology Clin N Am. 2004;22:27-43

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Diabetes mellitus • Acceptable metabolic control: – No ketonuria – Normal serum electrolytes – HbA1c within target range for age: • < 5 years: 7 – 9% • 5 – 13 years: 6 – 8.5% • > 13 years: 6 – 8%

Rhodes ET. Anesth Analg 2005;101:986 –99 10/15/09

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Insulin half life

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Insulin correction factor

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Mixed insulin regime (NPH/Lente)

+

No 10/15/09

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Lantus insulin regime No

Yes

No 10/15/09

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Insulin pump – for surgery < 2h

No

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Insulin pump  Surgery > 2h

No

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Oral hypoglycemic agents • Hold on the morning of surgery

No

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Post-operative DM management

No

Yes

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Perioperative VTE prophylaxis

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Perioperative VTE prophylaxis

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VTE risk of Surgery

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VTE Risk in the ICU

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• Child 1–2 months – 750 ug/kg s.q. bid. • Child 2 months–18 years – 500 ug/kg s.q. bid. – Maximum dose 20 mg s.q. bid.

• Adolescents of >40 kg weight – Adult dosing of 40 mg qday

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Psychological preparation of the children for surgery • 50-75% of patients develop significant anxiety

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Anesthesiology Clin N Am. 2005;23: 597- 614

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Thank you!

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