Canadian Journal of Anesthesia

, 53:1244 | Cite as

Review article: Age related alterations in respiratory function — anesthetic considerations

Cardiothoracic Anesthesia, Respiration and Airway

Abstract

Purpose

This review examines the effect of aging on pulmonary reserve. Special emphasis is placed on how anesthetic and surgical factors may impose substantial stresses on the respiratory system of elderly patients, leading to increased risk for postoperative pulmonary complications including respiratory failure.

Source

A MEDLINE-based English-language literature search was undertaken for the period 1966–2006, and an EMBASE search covered the overlapping period 1988–2006. Selected articles were limited to those applying to elderly subjects/patients.

Principal findings

Age-related loss of the lung static recoil forces, stiffening of the chest wall and diminished alveolar surface area lead to a decrease in vital capacity, an increase in residual volume, decrease in expiratory flows and increased ventilation-perfusion heterogeneity. Respiratory muscle strength consistently declines with age further increasing the work of breathing. While gas exchange may be well preserved at rest and during exertion, pulmonary reserve is diminished, and under conditions of positive fluid balance, positioning for surgery, and increased metabolic demand, postoperative respiratory failure can occur. Increased sensitivity to respiratory depressants and muscle weakness pose additional risks for the development of postoperative respiratory complications in elderly patients. Regional anesthetic techniques provide for superior postoperative analgesia, without necessarily altering the frequency of postoperative pulmonary complications in the older surgical population.

Conclusion

Alterations in respiratory physiology associated with aging must be appreciated to anticipate and minimize potential complications associated with surgery and anesthesia in the elderly. Individualized care to optimize preoperative cardiorespiratory function, minimize intraoperative respiratory pertubations, and to gently restore postoperative pulmonary function are essential anesthetic goals for elderly patients who require surgery.

Article de synthèse: Les modifications de fonction respiratoire liées à l’âge — considérations anesthésiques

Résumé

Objectif

Cet article traite de l’effet du vieillissement sur la réserve pulmonaire. En particulier, on se tourne vers les facteurs anesthésiques et chirurgicaux qui imposent un stress substantiel sur le système respiratoire des patients âgés, en les mettant à risque de complications respiratoires postopératoires, dont l’insuffisance respiratoire.

Source

Une recherche des articles publiés en langue anglaise de 1966 à 2006 a été entreprise en se servant de MEDLINE. La période 1988–2006 a aussi été fouillée avec EMBASE. On a sélectionné que les articles portant sur les patients ou sujets âgés.

Constatations principales

Avec l’âge, l’atténuation de la force statique de recul des poumons, la rigidité de la cage thoracique et la diminution de la surface des alvéoles produit une réduction de la capacité vitale, une augmentation du volume résiduel, une diminution des débits expiratoires et une plus grande inadéquation ventilationperfusion. La force des muscles respiratoires diminue constamment avec l’âge, ce qui augmente le travail respiratoire. L’échange gazeux est normal au repos et pendant l’exercice, mais la réserve pulmonaire est diminuée. Ainsi, avec une surcharge liquidienne, un positionnement pour la chirurgie et une demande métabolique accrue, une insuffisance respiratoire peut survenir en période postopératoire. Les patients âgés sont plus sensibles aux médicaments qui dépriment la respiration et leurs muscles sont plus faibles, d’où un risque augmenté de complications respiratoires postopératoires. Les techniques d’anesthésie loco-régionales produisent une analgésie postopératoire de qualité, sans toujours modifier l’incidence de complications pulmonaires postopératoires chez les sujets âgés.

Conclusion

On doit tenir compte des changements physiologiques respiratoires découlant du vieillissement pour prévoir et atténuer les complications qui peuvent survenir suite à une chirurgie et une anesthésie chez les sujets âgés. L’anesthésiologiste doit viser un traitement individualisé pour optimiser la fonction cardiorespiratoire avant la chirurgie, limiter l’atteinte respiratoire pendant la chirurgie et assurer une récupération en douceur de la fonction pulmonaire en postopératoire.

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Copyright information

© Canadian Anesthesiologists 2006

Authors and Affiliations

  1. 1.Department of AnesthesiologyMayo Clinic College of MedicineRochesterUSA
  2. 2.Division of Pulmonary and Critical Care MedicineMayo Clinic College of MedicineRochesterUSA

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