A prospective Randomized Comparative analysis between LMA vs ETT for Recovery time in Preterm infants for ROP eye surgeries

This study was designed to compare the recovery time between LMA vs ETT in preterm babies undergoing ROP eye surgeries. In this study we want to establish which mode is safer as well as better for airway management in preterm babies. We hypothesize that LMA will have better recovery  time than ETT in preterm babies undergoing ROP eye surgeries.

Primary Objective: To observe postoperative recovery time between laryngeal mask airway and ETT that is being used in  infants presenting for ROP procedures.

Secondary Objective: To study this population in terms of 1) Patient demography- birth weight, birth week, gender 2)First pass success rate 3) Duration of insertion 4) Ease of insertion 5)Number of attempts 6)Airway adjunct used 7)Desaturation, bradycardia during insertion 8)Time for extubation 9)Perioperative complication 10)Transfer to NICU for mechanical ventilation

A total of 40 Preterm babies of less than 1 year of age of either gender belonging to ASA physical status I,II,III will be recruited after receiving the parents willful consent.  Patients will be randomly allocated to LMA group and ETT group of 20 each.

Randomization will be achieved using a computer-generated random number table with an allocation ratio of 1:1. Allocation concealment will be maintained using sequentially numbered sealed opaque envelopes. Envelopes will be prepared by an independent person not involved in the study. Each envelope will contain a number which will allocate the participant to either Endotracheal group (ET group1) and Laryngeal mask airway ( LMA Group 2). The allocation sequence will be accessed only when study data collection is complete or in any instance where unblinding of the study is thought to be essential in the provision of appropriate patient care.

Forty patients will be randomly divided into two groups of twenty in each – Group 1 and Group 2 based on the intervention received.

Group 1 (ET group): Endotracheal intubation will be done ( n = 20).

Group 2 (LMA group): Laryngeal mask airway will be inserted(n = 20).

Upon arrival of the patient in the OR, an anaesthesiologist who is not involved in the study or in the care of the patient will open the sealed opaque envelope containing group allocation. The intubation or LMA insertion will be done according to the group allocation. The patient guardian will be unaware of the group allocation.

ANAESTHESIA TECHNIQUE

PREOPERATIVE :

·       A detailed routine preoperative evaluation will be done one day prior as per standard practice on all selected patients.

·       The post conceptual age, birth weight, gender, recent weight , history of NICU stay, history of mechanical ventilation or oxygen therapy, any other significant history will be noted.

·       The patients will be carefully examined for breath holding spells and if present the duration of spells and associated cyanosis or bradycardia.

·        Adequate fasting will be maintained as per standard guidelines.

IN THE OPERATING ROOM :

·       After confirming adequate fasting, patients will be taken to operation theatre table and standard ASA monitors will be attached.

·        Operation theatre temperature will be kept warm to prevent hypothermia in babies.

·       Inhalational induction of anaesthesia will be done using 100% O2 and titrated doses of Sevoflurane and maintenance of anaesthesia will be done using 50% O2 in air and titrated doses of Sevoflurane to maintain minimum alveolar concentration (MAC) >1.

·       An appropriately sized intravenous cannula will be secured.

·       Administration of Injection Atracurium (0.2–0.5 mg/kg) will be given in ETT group whereas injection atracurium will be avoided in LMA group.

·       Weight appropriate supraglottic airway device and endotracheal tube will be selected based on manufacturer’s guidelines.

·       The type of LMA or ETT device use will be decided by the concerned anaesthesia consultant and surgeon. A senior anaesthetist experienced in paediatric cases will only insert the LMA/ ETT and confirm the placement. Successful insertion of LMA/ETT will be defined on confirming the ventilation with capnograph, chest rise, and acceptable leak without overtly increasing airway pressure.

·       If fail to ventilate or/and secure the airway, other rescue measures including endotracheal intubation, or awakening the patient can be attempted by the concerned anaesthetist depending upon the situation.

·       PSV mode of ventilation will be used in case of LMA targeting a tidal volume of 6-8 ml/kg and VCV /PCV mode of ventilation will be used in case of ETT insertion targeting a volume of 6-8 ml/kg body weight.

·       Maintenance of anaesthesia will be done with isoflurane and 50% O2 in air to target a MAC of 1.2.

·       Hemodynamic parameters will be noted.

·       All the patients will receive injection Paracetamol 10 mg/kg IV.

·       Reversal of neuromuscular blockade will be achieved by Neostigmine 70mcg/kg and Glycopyrrolate 10mcg/kg in patients of ETT group.

·       The LMA/ETT will be removed in an awake state and the patient will be observed for any complication in the neonatal intensive care unit (NICU).

·       The following parameters will be studied.

Parameters:

·       Success: Number of attempts needed to insert and secure the LMA/ETT with confirmed ventilation will be counted and noted.

·       The duration of insertion will be measured from picking up of LMA/ETT to the confirmation of LMA/ETT placement by two square wave patterns in the capnogram on the monitor.

·       The ease of insertion will be defined by objective criteria as mentioned in the Table 1.

 

Easy placement

Difficult placement

|Time for insertion

<30sec

30sec

|First Attempt success rate

Success

Failure

|Adjuncts or Manoeuvres

No

Yes

Table1: Objective criteria for defining easy vs difficult placement of LMA/ETT

·       A difficult placement will be defined by the presence of any one criterion while an easy placement can only be defined by presence of all three criteria.

·       Any Incidence of desaturation or bradycardia requiring intervention/treatment, LMA/ETT displacement, re-insertion, and need for endotracheal intubation in LMA group and mechanical ventilation will be noted.

·        Recovery time (removal of LMA/ETT after end of surgery),Delayed extubation time>30 min, Desaturation With SpO2 < 95% ,Apnea >15 secs, bradycardia,manual ventilation and reintubation requirements, shifting patient intubated to NICU for mechanical ventilation will be noted.

·       Occurrence of any postoperative airway complication or evidence of airway trauma (i.e., presence of blood-tinged secretions on the dorsum of the LMA cuff) will be noted.

POSTOP:

·       Patients will be shifted to NICU for monitoring either extubated or intubated.

·       Any postoperative complications in NICU will be noted .

DATA COLLECTIONData will be collected from the anesthetic chart and separate proforma which are specifically made for the intraoperative and postoperative monitoring of these patients. All documentation relating to the study will be stored in an anonymized case report file unique to each patient.