Is fibreoptic percutaneous tracheostomy in ICU a breakthrough.

BACKGROUND: In ICUs, bedside percutaneous tracheostomy (pct) is commonly performed, but it is associated with certain drawbacks as paratracheal placement, posterior tracheal wall injury and tracheoesophageal fistula. To address these fibreoptic bronchoscope (FOB) guided PCT was introduced. We aimed to compare both these methods. PATIENTS #ENTITYSTARTX00026;
METHODS: We compared 60 age & sex matched patients into two groups of 30 each. In group 1 tracheostomy was performed by the conventional Ciaglia's method. In group 2, a fibreoptic bronchoscope was used in addition with the aid of an assistant.
RESULTS: The fiberoptic method took more time than the conventional method. (18±3min vs 15±2min (p=0.001)). The average no. of attempts at insertion of needle was 2.4 in group 1 and 1.2 in group 2 (p=0.001). The fall in SpO2 to <90% was seen in 1 patient in group 1 and in 6 patients in group 2, so much so that the procedure had to be abandoned in 2 patients.
CONCLUSION: FOB though definitely advantageous over CPCT in terms of lesser complications and being highly useful in the obese, short necked, and those with scar marks, is not without drawbacks such as requirement of additional staff and increased expenditure. The main being inability to be used in patients with low respiratory reserve. Overall it would be complimentary for any ICU to have FOB facility and must be used in select group of patients.

Traditionally tracheostomy has been performed by surgeons in operation theaters. But in ICUs, the patients are so much critical that their condition does not permit shifting to OTs. Hence the concept of bedside percutaneous tracheostomy was introduced.1 But PCT was associated with certain drawbacks as paratracheal placement, posterior tracheal wall injury and tracheoesophageal fistula.2 To address these, FOB guided PCT was introduced.3 We aimed to compare both these methods

PATIENTS & METHODS

We compared 60 age & sex matched patients into two groups of 30 each. In group 1 tracheostomy was performed by the conventional Ciaglia's method.4 In group 2, a fibreoptic bronchoscope was used in addition with the aid of an assistant.5 In both the groups, patients were placed supine and a rolled sheet placed under the shoulder blades to extend the neck. The area around the neck was cleaned and draped. The patients were sedated with propofol (2mg kg-1) and fentanyl (1μg kg-1). FiO2 was increased to 100% in all. In group 1, the ETT was withdrawn just proximal to vocal cords by D/L, a 14G needle was introduced in between the 2nd and 3rd tracheal ring, identified by palpation about 1.5-2 cm below the cricoids.6 After successful aspiration of air, a guidewire was passed through the needle. Thereafter serial dilators were passed over the guidewire. After sufficient dilatation the tracheostomy tube was inserted through the opening. We used Storz fibreoptic videoscope in Group 2 (Figure 1). One person inserted the bronchoscope through the ETT upto the tip and the tube withdrawn under direct vision. The skin over the anterior neck was transilluminated and a needle was inserted in between the 2nd & 3rd tracheal rings under direct vision (Figure 2). Care was taken that neither the needle nor dilators touched the posterior tracheal wall (Figure 3). Rest of the procedure was similar to group 1. A postprocedure chest Xray was performed in all as a precautionary measure.

Figure 1

The Storz fibreoptic videoscope

Figure 2

Insertion of needle through tracheal wall

Figure 3

Ideal position of needle or dilator in trachea

Purposeful view of mechanism of posterior tracheal wall injury

The parameters observed included

Duration of procedure from skin puncture to insertion of cannula

No. of attempts at skin puncture

Complications, if any

Oxygen saturation

Preprocedure & postprocedure arterial pH & pCO2.

Exclusion Criteria

Age<18, >65

Coagulation disorders

Thyroid swellings

Local site infection

Raised ICT7

RESULTS

The fiberoptic method took more time than the conventional method. The mean time to perform the procedure was 15±2min in group 1 and 18±3min in group 2 (p=0.001). The average no. of attempts at insertion of needle was 2.2 in group 1 and 1.2 in group 2 (p=0.001) (Table 1). The fall in SpO2 to <90% was seen in 1 patient in group 1 and in 6 patients in group 2, so much so that the procedure had to be abandoned in 2 patients. The change in pH and pCO2 was within 10% in both the groups. Hemmorhage was seen in 3 patients in group 1 and 2 in group 2. 3 patients in group 1 suffered paratracheal placement, while none in group 2. In 1 patient in group 1 we encountered posterior tracheal wall injury leading to tracheoesophageal fistula formation (Table 2).

Table 1

Observed parameters

Table 2

Complications encountered

DISCUSSION

FOB PCT took on an average more time than CPCT, but it required lesser no. of attempts and had no complications as regards to posterior tracheal wall injury or paratracheal placement. FOB did not offer any direct advantage in controlling haemmorhage. On the contrary it made the procedure more cumbersome by obscuring the view. Several reports state that fiberoptic tracheostomy is associated with hypercarbia and acidosis, with deleterious effects on ICT.89 In our study, though in few patients there was repeated fall in O2 saturation, we did not encounter hypercarbia or acidosis, probably because we immediately withdrew the bronchoscope and administered 100% O2. Later on reviewing the records we found that this was because of low respiratory reserve due to underlying pathology such as ARDS. So FOB was not the primary cause of falling saturation.

FOB though definitely advantageous over CPCT in terms of lesser complications and being highly useful in the obese, short necked, and those with scar marks, is not without drawbacks such as requirement of additional staff and increased expenditure.10 The main being inability to be used in patients with low respiratory reserve. Overall it would be complimentary for any ICU to have FOB facility and must be used in select group of patients.

Authors disclosure: Authors have no conflict of interest & financial consideration to disclose.