COMPLICACIONS DE LA VENTILACIÓ MECÀNICA NO INVASIVA Dr. Miquel Ferrer UVIIR, Servei de Pneumologia, Hospital Clínic, IDIBAPS, CibeRes, Barcelona. E- mail: miferrer@clinic.ub.es Barcelona, 3 de novembre de 2010 www.idibapsrespiratoryresearch.org
Complicaciones y resolución de problemas Complicaciones de la VNI Predictores de fracaso: IR hipercápnica IR hipoxémica Causas frecuentes de fracaso Factores que contribuyen al fracaso de la VNI Relacionados con el entorno y/o equipo asistencial Contraindicaciones de la VNI Relacionados con el paciente Técnicos
How to Reduce Air Leaks During NIV Proper interface type and size Proper securing system Mask-support ring Comfort flaps Tube adapter Hydrogel or foam seals Chin strap Lips seal or mouth taping Nava S et al. Respiratory Care Jan 2009 vol 54 no1
How to Reduce the Risk of Skin Damage During NIV Proper harness and tightening Skin and mask hygiene Nasal-forehead spacer To reduce the pressure on the bridge of the nose Forehead pads To obtain the most comfortable position on the forehead Cushioning system between mask prong and forehead Remove patient s dentures when making impression for molded mask In home care, replace the mask according to the patient s daily use Skin pad Nava S et al. Respiratory Care Jan 2009 vol 54 no1
Úlceras cutáneas
Riesgo de lesión cutánea
Una solución posible: la máscara facial total
Otra solución: Helmet
Úlcera por presión No siempre aparecen donde se espera!!!
Predictores de fracaso de la ventilación no invasiva Insuficiencia respiratoria hipercápnica Insuficiencia respiratoria hipoxémica
Predictors of failure: NIV for hypercapnic respiratory failure Advanced age Higher acuity of illness (APACHE score) Uncooperative Poor neurological score Unable to coordinate breathing with ventilator Large air leaks Edentulous Tachypnoea (>35/min) Acidaemia (ph <7.18) Failure to improve ph, heart and respiratory rates or Glasgow Coma Score within the first 2 hours Soo Hoo et al. Crit Care Med 1994; 22: 1253 61 Ambrosino et al. Thorax 1995; 50: 755 7 Confalonieri et al. Eur Respir J 2005; 25: 348 55
Non-COPD conditions: Pneumonia (n=37) Neuromusculoskeletal disorders (n=11) Pulmonary edema (n=9) Bronchiectasis (n=5) Sepsis (n=3) Asthma (n=3)
Outcomes of NIV in non-copd patients by specific diagnosis
Variables associated with in-hospital NIV failure (n=22/120)
Risk stratification of NPPV failure in 1,033 consecutive patients admitted to experienced hospital units Two intensive care units Six respiratory intermediate care units Five general wards NPPV was successful in 797 patients
At admission
After 2 h of NIV
Predictors of failure: NIV for hypoxaemic respiratory failure Diagnosis of ARDS or pneumonia SAPS 35 Lower PaO 2 /FIO 2 (100 or below) Low ph Age >40 years Septic shock Multiorgan system failure Failure to improve PaO 2 /FIO 2 >146 within first hour Antonelli et al. Intensive Care Med 2001; 27: 1718 28. Rana et al. Crit Care 2006; 10: R79.
Eight ICUs n=354: Success: 246 Failure: 108
ICU mortality CAP HAP Pulmonary ARDS Extrapulmonary ARDS CPE Trauma n=0 n=1 n=0 n=4 n=7 n=0 n=10 n=33 n=18 n=8 n=7 NIV-success NIV-failure n=9 0 20 40 60 80 100 % Independent predictors of NIV failure: Age > 40 yrs PaO 2 /FiO 2 <146 ARDS or CAP SAPS >35
100 80 % 60 40 20 Mortality in patients failing NIV p<0.01 Failure rate: 70% Patients with shock: 100% Independent predictors of NIV failure (excluded patients with shock): Metabolic acidosis Severe hypoxemia 0 Actual Predicted
Causas frecuentes de fracaso de la ventilación no invasiva Relacionados con el entorno o el equipo asistencial Relacionados con el paciente Factores técnicos
Common reasons for NIV failure Environmental/caregiver team factors Lack of skilled, experienced caregiver team Poor patient selection Lack of adequate monitoring Selection guidelines for NIV in the acute setting Appropriate diagnosis with potential reversibility (COPD, congestive heart failure Establish need for ventilatory assistance Moderate to severe respiratory distress and Tachypnoea (>24 for COPD, >30 for CHF) Accessory muscle use or abdominal paradox Blood gas derangement: ph <7.35, PaCO 2 >45, or PaO 2 /FiO 2 <300
Contraindications of NIV Respiratory or cardiac arrest Too unstable: Shock Myocardial infarction requiring intervention Uncontrolled ischaemia or arrhythmias Uncontrolled upper GI bleed Unevacuated pneumothorax Unable to protect airway* Excessive secretions Poor cough Impaired swallowing Aspiration risk* Distended bowel; obstruction or ileus Frequent vomiting Uncooperative or agitated* Unable to fit mask Recent upper airway or oesophageal surgery Multiorgan system failure (more than 2) *Relative contraindications
Common reasons for NIV failure Patient-related factors Intolerance Mask problems: Discomfort Poor fit Skin ulceration Claustrophobia Agitation Excessive secretions, inability to protect airway Progression of underlying disease
Approach to the agitated/intolerant patient using NIV
Common reasons for NIV failure Technical factors Inadequate equipment Failure to ventilate Failure to oxygenate Patient ventilator asynchrony Air leaks
How do ventilators perform in the presence of leaks? Portable or NIV ventilators ICU ventilators With NIV modes Without NIV modes
Varying conditions had a generally small effect on triggering times, suggesting that : There is a largely unavoidable element to the triggering delays intrinsic to the design of the ventilators Effective compensation of leaks
Eight ICU ventilators featuring an NIV mode. Tests conducted in: Absence of leaks Presence of leaks with and without activation of the NIV mode Trigger delay
Inspiratory trigger pressure drop Workload of triggering
In most ventilators, leaks: Increased trigger delay and workload Decreased pressurization and delayed cycling NIV mode partly corrected these problems: Large variations between machines In some ventilators the NIV mode worsened the leak-induced dysfunction Leaks interfere with several key functions of ICU ventilators NIV modes can correct part or all of this interference Wide variations between machines in terms of efficiency
August 2010 65 patients included 5 different ICU ventilators, with and without NIV algorithm NIV algorithms can reduce asynchronies due to leaks: This confirms bench test results, but Some of these algorithms can generate premature cycling
Bilevel or ICU ventilators in the presence of leaks?
Comparison of nine ICU ventilators with NPPV function with a bilevel ventilator in the presence of leaks At baseline all ventilators: Delivered adequate tidal volumes Maintained airway pressure Synchronized with the simulator (no missed efforts or autotriggering) As the leak was increased, all ventilators except the Vision and Servo I: Needed adjustment of sensitivity or cycling criteria to maintain adequate ventilation Some transitioned to backup ventilation
Significant differences in triggering and cycling were observed between the Servo I and the Vision ventilators. The Vision appears the optimal ventilator for NIV conditions: No need for adjustment of sensitivity or cycling criteria Optimal triggering performance
Fracaso de la ventilación Nunca olvidar la válvula!!! Válvula espiratoria Evita la re-inhalación de CO 2
Successful NIV: Important factors More likely with a good team A skilled, experienced staff helps to optimize outcomes The underlying disease is an important determinant Selecting appropriate patients and monitoring them closely Severity at presentation Change in physiology after a short period of NIV In failure to ventilate or oxygenate, rapidly assess for reversible contributing factors Be prepared to intubate without undue delay if rapid reversal cannot be achieved A systematic approach to troubleshooting can help assure the best possible NIV outcomes