To best answer the question by wha...

To best answer the question by what mode long patients should be intubated before receiving tracheostomy, we ne to answer subsidiary fixs of questions: What are the advantages and disadvantages of tracheostomy and postponeed endotracheal intubation? What are the comparative complication rates? What are the major mechanisms causing complications? Can the rates of complication be modified? and What is the circulating pragmatic experience from use of tracheostomy in the critically ill, and can a maximum time be locate for prolonged oral or nasal endotracheal intubation in different diagnostic groups?

AdvaNtages and Disadvantages

The advantages and disadvantages of endolaryngeal tubes and tracheostomy tubes have been compared and were well [TABULAR DATA OMMITTED] reviewed.[1] The comparative complications are shown in Table 1 The major differences are in airway damage with an increased incidence of laryngeal injuries seen with endolaryngeal tubes while an increased incidence of late stenosis is seen after tracheostomy. Immediate and cruel complications are seen more not seldom after tracheostomy (pneumothorax, 0-5%; bleeding from stomal verge 5%; and mortality attributable to the technique, <2% for tracheostomy, <1/5000 for intubations).[1]

Laryngeal Injuries

Damage from endotracheal tubes to mucosa in the airway is immediate and appears to outcome from mechanical effects of the tube.[2] Damage to the larynx be founds after more prolonged periods and has been best studied in man by dint of Whited.[3-5] He described " symmetrical vocal cord paresis or paralysis associated with arytenoid and posterior commissure edema and erythema."[3] Spontaneous recuperation usually occurs over days to weeks,[3] although a 6% incidence of posterior commissure stenosis suitable to fibrosis in the posterior endolarynx has been noted.[4] This series of 200 prospectively enlisted subjects was divided into 3 groups: (1) 2-5 days intubated, (2) 6-10 days intubated, and (3) 11-24 days intubated. Posterior commissure stenosis was seen in all 3 assemblages but the incidence and severity increased with increasing long duration of intubation.[5] Conversion to tracheostomy was preventive. He conclud that prolonging intubation beyond 10 days is unacceptable as a routine policy. Others[6] have indicateed that these problems become particularly acute and relentless in association with insulin-dependent diabetes mellitus and female gender

Late Tracheal Stenosis

Late tracheal stenosis after tracheostomy has received sporadic attention in case reports since at least 1964[7] In follow-up of 237 patients (120 responding) who had more than 3 days of intubation in a large multidisciplinary ICU at Victoria Hospital,[8] 52 were intubated 7 days or les and sole 1 of these had necessary surgical removal of a granuloma; 63% had no complication. Of 17 intubated more than 7 days, 48% had no complication, and the remainder had minor complications -- greatest in number frequently hoarseness, which did not persist. Of patients who had tracheostomy after postponeed intubation, only 23% were independent from complications. These authors conclud that tracheostomy should be avoided as extended as possible, but that every-day evaluation of the larynx should be undertaken after 7 days.

The immediate and harsh complications from tracheostomy[10] are not unique to this means of airway management,[10] yet they are more prominent than with endolaryngeal intubation and are therefore also involved in this decision. Although a otolaryngologists do recommend early tracheostomy because of the lower incidence of laryngeal injury, this decision is not to be undertaken lightly in the face of increased incidence of sharp and late complications, although it usually becomes necessary to perform a tracheostomy after 10-12 days of intubation. single group attempted to provide a decision-making tool based onward an injury-severity score[11] (ISS) to permit assessment of long-term wants for ventilation. ISS scores >30 were always associated with intubation for more than 7 days; therefore, common could opt for early tracheostomy if the ISS was >30

Summary

The decision for timing of tracheostomy remains controversial. The relative complication rates in sum of two units retrospective series,[12,13] in which 79 and 150 critically ill patients were examined, respectively, showed increased incidence of late complications with tracheostomy and l Petty's group[13] to bring to an end "The value of tracheotomy when an artificial airway is required for periods as lengthy as 3 weeks is not supported by means of data obtained in this study" [TABULAR DATA OMMITTED]

common Pragmatic Experience

With this war of words in mind, the philosophic position adopted since 1974 by way of the Critical Care Service at Mayo in conjunction with our medical and surgical colleagues has been that tracheostomy should be considered at day 10 of intubation and performed then unles extubation or death was imminent. To examine this in practice, we reviewed the Mayo experience with lengthened mechanical ventilation since 1970 and reexamined a patient series consider probableed in 1982-83 and published[14] in 1986