Non-invasive positive pressure ventilation in the PICU What is the daily practice of mechanical ventilation in ICU In adults (in the years 1996 / 1997: Esteban A et al. AJRCCM 2000; 161:1450–1458 In pediatrics (in the year 1999): ETT in 635 (96%; 95% CI: 94–97) of patients, tracheostomy in 11 (2%; 95% CI: 1–3), facial mask in 10 (1.5%; 95% CI: 1–3). Farias A et al. Intensive Care Med 2004; 30:918–925 NIPPV in the Pediatric Intensive Care Unit Geneva experience 1998 - 1999 Number of pediatric patients hospitalized in the PICU over a 2-year period: General pediatrics: Cardiovascular surgery: General surgery: Neurosurgery: Transplantation unit: Onco-hematology: Orthopedics: 771 215 279 133 69 27 13 35 (28%) (36%) (17%) (9%) (3%) (2%) (5%) Ventilated patients: 479 (62%) Intubated and ventilated patients: 416 (87%) Ventilatory support with NIPPV or CPAP 63 (13%) NIPPV in acute pediatric respiratory failure Geneva experience 1998 - 1999 n = 63 CPAP: NPPV (BiPAP): NPPV and CPAP: 30 29 4 Etiology: - infectieuse pneumopathy: n = 20 - resp. insuffiency postoperatively: n = 10 (orthopedic surgery: n = 3; diaphragmatic palsy: n = 5) - upper airway obstruction: n = 4 (incl. postextubation stridor) - acute heart failure: n = 16 (postoperative CHD, cardiomyopathy, myocarditis) - septicemia: n = 4 High risk of respiratory distress in infants and small children Small airways = high airway resistance Compliant chest wall = low FRC Relatively “inefficient” diaphragm The diaphragm should set off the inward motion of the rib cage to maintain tidal volume constant, something which it can only do to a limited extent and will result in paradoxic thoraco-abdominal movements. Chest wall distortion represents a pressure-induced change in volume and constitutes waste work which has an enormous energy cost Objectives of Noninvasive Ventilation in Pediatric Patients With Respiratory Disorders Avoid intubation Teague WG Pediatric Pulmonology 2003;35:418–426 Indications / Benefits of NIPPV in the PICU Early case reports showed: Improvement of clinical manifestation of respiratory distress and respiratory gas exchange in children with AHRF Avoid or delay endotracheal intubation ? Treatment of upper airway obstructions (stenting the airways) Treatment of atelectasis Treatment of exacerbations of neuromuscular disease Facilitation of weaning from invasive ventilation (e.g. post-operative in patients with restrictive lung disease) NIPPV in acute hypoxic respiratory failure: Benefit and treatment failures in 3 pediatric case series 4 Rimensberger PC Swiss Medical Weekly 2000;130:1880–6 NIPPV / CPAP in ARF: Treatment failures Geneva experience 1998 - 1999 6 / 63 (9.5 %) on CPAP patient # 1 (4 months): patient # 2 (10 months): patient # 3 (6 months): on NPPV (BiPAP) patient # 4 (3 years): patient # 5 (15 years): patient # 6 (15 years): Bronchiolitis and BPD DORV, Tetralogy of Fallot: postoperative TGV, VSD postoperative BT-shunt ARDS, pneumonia Fungal pneumonia and sepsis in immuncompromised patient post lung transplantation Orthopedic patient with postoperative paraplegia NIPPV in infants with AHRF 6 infants with AHRF of various etiology Pressure support: IPAP 14 ± 0,5 cmH2O; EPAP 7,3 ± 1 cmH2O Ti max: 0,6 ± 0,1 s ; insp. rise time: 100 ms. pCO2 RR F. Vermeulen et al. Annales Françaises d’Anesthésie et de Réanimation 2003; 22: 716–720 NIPPV in children upper airway obstruction chronic: obstructive sleep apnea (OSA) a) anatomic obstruction of nasopharyngeal airways b) intermittent collapse of the nasopharyngeal airway - CPAP or NIPPV to prevent upper airway collapse acute: infectious conditions (epiglotitis, croup) or foreign body - CPAP or NIPPV works well in postextubation croup No published experience with helium and NIPPV in these conditions PEEP: Tracheomalacia No PEEP PEEP 10cmH2O Quen Mok, Great Ormond Street Hospital for Children, London CPAP: Tracheomalacia No PEEP CPAP 10cmH2O Quen Mok, Great Ormond Street Hospital for Children, London Case serie in pediatric status asthmaticus with severe hypoxemia Teague WG AJRCCM 1998; 157:542 prospective, non controlled case serie (n = 26) NPPV: nasal mask; S/T mode IPAP 13 ± 3 cmH2O; EPAP 7 ± 2 cmH2O; FiO2 0.68 ± 0.28 Results: 21 ± 27 hrs mean duration 169 ± 183 hrs O2 requirements 19/26 acutely improved 7/26 required intubation 11/26 did not well tolerate pH paCO2 (mmHg) paO2 (mmHg) pre-tx (n = 15) 7.36 ± 0.5 40 ± 10 87 ± 23 post-tx (n = 6) 7.42 ± 0.9 39 ± 14 94 ± 35 p > 0.05 for all comparisons NPPV in pediatric status asthmaticus: Case serie 120 25 100 20 * 80 pre NPPV 60 intubated 15 * post NPPV 10 40 20 * p < 0.05 * 5 * p < 0.05 0 FiO2 SO2 not intubated (19) FiO2 SO2 intubated (7) The oxygen response test? not intubated 0 Hospital Days PICU days Teague WG AJRCCM 1998; 157:542 • was safe • allowed to shorten the length of ICU and hospital stay • did not prevent intubation in a subset of patients NPPV in acute cardiogenic pulmonary edema (ACPE) n o. of p a tie n ts stu d y d e sign ve n tila tion m od e tre a tm e n t Re su lts fa ilu re CPAP 0 vs 35% n o d iffe re n ce in le n gth of ICU sta y H offm a n n B 29 BiPAP CCM 1999;25 op e n p rosp e ctive in 1 p a tie n t im p rove d SO 2 a n d d e cre a se d p CO 2 in a ll p a tie n ts Ru ste rh olz T 26 BiPAP CCM 1999;25 op e n p rosp e ctive 21% im p rove d SO 2 a n d d e cre a se d p CO 2 in re p on d e rs Be rste n AD NEJM 1991;325 CPAP vs O 2 (patients who responded were hypercapnic, those who failed were hypoxemic non-hypercapnic patients) with the exception of patients with acute myocardial infarction, CPAP and/or NPPV is efficient in ACPE with hypercapnic ARF Perioperative use of noninvasive ventilation Non-invasive mask ventilation in 25 patients with respiratory failure preand/or postoperative Success rate of 68%, but different in respect to the varying causes of respiratory failure. CONCLUSION: With noninvasive mask ventilation it is possible to avoid in some patients with acute postoperative respiratory failure complications who are referred to intubation. In patients with postoperative decompensation of chronic respiratory failure postoperative treatment becomes easier, in extraordinary cases the method makes surgery possible. Karg O et al. Med Klin 1996; 91 Suppl 2:38-40 NIV for physiotherapy NIV for physiotherapy NIV for physiotherapy NIV for physiotherapy NIPPV in children with ARF: Complications severe: air leaks gastric perforation aspiration decrease in CO minor: skin irritation / skin breakdown nasal dryness conjunctivitis Physiological Factors Unique to Pediatric Patients Promoting Complications of NIPPV Teague WG Pediatric Pulmonology 2003;35:418–426 NIPPV in children with ARF: Technical aspects setting: restricted to acute care units - pulsoxymeter - tcpCO2 / TECO2 - cardiorespiratory monitoring NIPPV in children with ARF: Technical aspects interface: soft preformed nasal mask appropriately sized usually work and are much better tolerated - chin strips can reduce the air leak NIPPV in children with ARF: Technical aspects interface: soft preformed nasal mask appropriately sized usually work and are much better tolerated - chin strips can reduce the air leak NIPPV in children with ARF: Technical aspects interface: soft preformed nasal mask appropriately sized usually work and are much better tolerated - chin strips can reduce the air leak alternatives: 1) nasal prongs (typically used in newborns and small infants) 2) full face (nasal-oral) masks - but increased risk of aspiration in small children (immature airway protective response) NIPPV in children with ARF: Technical aspects DELIVERY SYSTEMS - CPAP devices need bias flow: - to compensate for mask leaks - to maintain constant airway pressure during in- and expiration - Volume-cycled devices need variable flow (pressure controlled / pressure targeted) should be able to deliver high inflation flows: - to allow to match inspiratory flow demands of the patient to reduce WOB, - to compensate for leaks need automated cycle feature (apnea) NIPPV in children with ARF: Technical aspects DELIVERY SYSTEMS - flow-triggered devices with independent adjustements of IPAP and EPAP one way expiratory valve to prevent rebreathing (EPAP regulates CO2 elimination: minimum 3 cmH2O) NIPPV in children with ARF: Technical aspects ventilators: NIPPV ventilators (typ: BiPAP; mode: S/T) ICU ventilators (PC / Pressure support) sensitive flow trigger threshold one way expiratory valve to prevent rebreathing Not optimal for small children: - No back-up rate - Very low (5%) fixed expiratory trigger / flow termination at very low flows Patient-Ventilator Interaction Patient-ventilator asynchrony by inspiratory trigger insensivity Insp effort trigger vent COPD PSV Ineffective effort (12) Ineff trig abrupt dec exp flow RR 24 RR 60 E. Kondili, G. Prinianakis and D. Georgopoulos Pressure-Support and flow termination criteria The non synchronized patient during Pressure-Support (inappropriate end-inspiratory flow termination criteria) Nilsestuen J Respir Care 2005;50:202–232. Pressure-Support and flow termination criteria Increase in RR, reduction in VT, increase in WOB Nilsestuen J Respir Care 2005 NPPV in acute or chronic pediatric respiratory failure: Which mode, which device and which interface? Infant (0 - 12 months) Small child (12 - 24 months) > 24 months AHRF Nasal CPAP (nasal prongs or mask) or NIPPV with a modified circuit Nasal CPAP or NIPPV with nasal or NIPPV with nasal or full face mask full face mask Upper airway obstruction Nasal or nasopharyngeal CPAP CPAP or NIPPV by nasal mask CPAP or NIPPV Tracheobronchomalacia CPAP with relatively high pressure levels CPAP with relatively high pressure levels CPAP with relatively high pressure levels Chronic RF in neuromuscular disease NIPPV NIPPV NIPPV Congestive heart failure or acute pulmonary edema Nasal CPAP Nasal or full face CPAP or NIPPV Nasal or full face CPAP or NIPPV Helmet-delivered CPAP and/or non-invasive pressure support ventilation in children? Need high flows to flush the system to avoid CO2-rebreathing Helmet-delivered NIPSV in children with acute hypoxemic respiratory failure (P/F ratio < 200) Piastra M et al. Intensive Care Med 2004; 30:472-476 Selection guidelines for NIPPV in pediatric ARF • Progressive respiratory failure or insufficiency in the absence of apnea or impeding cardiorespiratory collapse • Failure of NIPPV would not produce immediate morbidity or mortality • Relative cooperation (of a lethargic or sedated patient) • Adequate mask fit achieved Selection guidelines for NIPPV in pediatric ARF: Contra-indications • Ongoing emesis • Excessive bronchial secretions • Acute facial trauma • Upper airway protection not intact NIPPV in acute respiratory failure in children widespread use in PICU • commonly applied to avoid intubation / reintubation improve atelectasis (type I failure / AHRF) Improve alveolar hypoventilation (type II failure) facilitate early extubation (postoperative / restrictive lung disease - neuromuscular disease - scoliosis repair) despite popularity, therapeutic efficacy has never been evaluated NIPPV in pediatric ARF 1) NPPV is safe in pediatric patients with ARF 2) NPPV can improve oxygenation in mild to moderate hypoxemic respiratory insufficiency 3) May be particularly useful in patients in whom intubation should be avoided current pediatric NIPPV questions: - does NPPV in ARF prevent or delay intubation? - in which type of respiratory failure should it be used? - does NIPPV reduce mortality in ARF in children? - are ventilators appropriate for small children? ( mortality rate = 15%)