Implementation of On-table Extubation After Pediatric Cardiac Surgery in the Developing World

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Implementation Of On-Table Extubation After Pediatric Cardiac Surgery In The Developing World Rajnish K. Garg , Jameel K. Thareen , Akhter Mehmood , Masakazu Nakao , Vikram Basappanavar , Richie Jain , Monsy Sam , Abdul Ahad Khan , Roberto M. Di Donato PII: DOI: Reference:

S1053-0770(19)31201-7 https://doi.org/10.1053/j.jvca.2019.11.032 YJCAN 5596

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Journal of Cardiothoracic and Vascular Anesthesia

Please cite this article as: Rajnish K. Garg , Jameel K. Thareen , Akhter Mehmood , Masakazu Nakao , Vikram Basappanavar , Richie Jain , Monsy Sam , Abdul Ahad Khan , Roberto M. Di Donato , Implementation Of On-Table Extubation After Pediatric Cardiac Surgery In The Developing World, Journal of Cardiothoracic and Vascular Anesthesia (2019), doi: https://doi.org/10.1053/j.jvca.2019.11.032

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Implementation Of On-Table Extubation After Pediatric Cardiac Surgery In The Developing World

Rajnish K. Garga, Jameel K. Thareene, Akhter Mehmoodd Masakazu Nakaob Vikram Basappanavara Richie Jaina Monsy Samc Abdul Ahad Khanc Roberto M. Di Donatob,

From the Departments of Cardiac Anesthesiaa, Cardiac Surgeryb and Clinical Perfusionc, Al Jalila Children‟s Specialty Hospital, Dubai, Pediatric Intensive Cared, Dubai Hospital and Cardiac Surgerye, Al Qassimi Hospital Sharjah, United Arab Emirates

Correspondence: Rajnish Kumar Garg, M.D. Department of Pediatric Cardiac Anesthesia Al Jalila Children‟s Specialty Hospital P.O. Box 7662 Dubai United Arab Emirates E-mail: [email protected] Telephone: +971.4.2811653

All authors declare that they have no disclosure regarding funding or conflict of interest.

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BACKGROUND The biggest challenge in delivering quality healthcare services in developing countries is lack of resources (including mechanical ventilators, appropriate medications, equipment) as well as of experienced healthcare providers to cope with high clinical complexity. In the specific case of children undergoing heart surgery, traditional management protocols advocate a complex ritual of postoperative intensive care measures including continued elective overnight ventilation, narcotic sedation and occasionally paralysis, which may lead to increased post-operative morbidity and long intensive care unit (ICU) stay. This approach escalates the demand for beds, particularly in ICU, significantly adding to the huge economic burden on resourceconstrained hospital settings. Disconcertingly, this approach of overnight mechanical ventilation (MV) is perhaps more dogmatic than „individual patient‟-focused. On the other side, however, with improvement in the surgical expertise, perfusion technology and newer anesthetic drugs, successful on-table extubation (OTE), after intraoperative assessment on a case to case basis, is increasing amongst pediatric cardiac surgical units1 as OTE reduces morbidity, hospital and ICU stay2.

This was, in fact, our experience in a previous 60-bed pediatric cardiac surgical ICU which used to cater 10-12 pediatric cardiac surgeries a day [Narayana Institute of Cardiac Sciences, Bangalore, India]. On an average, 35-40 immediate postoperative patients happened to be on mechanical ventilation at any given time, along with a variable number of patients with chronic complications associated with mechanical ventilation, all together requiring an extensive involvement of trained staff. A major change that would safely reduce ICU stay, postoperative complications and, ultimately, manpower requirement was clearly needed. This led us to consider OTE

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as, possibly, the most radical solution of the problem. Herewith, we would like to share our experience with OTE in developing countries, initially in a large volume center and later in different hospitals, including those visited for charity missions. The purpose is also to review the literature on the current practice of OTE.

THE BEGINNING OF A NEW THOUGHT Historically, the reason for OTE in the developing world had been the lack of resources. Furthermore, the safety of this strategy in developing countries had been consistently shown, for example, in charity missions. Thereafter, OTE started appealing the developed world as a strategy for lowering costs and making better use of resources. Alongside, it had the obvious advantage of avoiding the adverse effects of mechanical ventilation, longer ICU and hospital stay3-5. So, if OTE offered such plausible clinical and financial benefits, why couldn‟t it be routinely practiced, i.e. considering every patient as a candidate for OTE, pending the decision to extubate based on individual intraoperative assessment?

Upon analysis of the literature, we observed that most types of pediatric cardiac surgical patients, even if undergoing complex neonatal surgery, had been proven potentially suitable for early extubation, i.e. within few hours after surgery in the ICU or even in the operating room6-12. This led us to wonder: is it really the predetermined patient risk category or, rather, the perioperative course of events that should indicate the need for continuing mechanical ventilation in the postoperative period? And what are the factors deterring us from extubating patients in the operating room after pediatric cardiac surgery? Therefore, inspired by the pioneering work of Barash et al.6 in 1980 and subsequent contributions by Preisman et al.4, Mittnacht et al.7 and

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other groups, we decided to adopt OTE as a routine practice, by considering every patient, irrespectively of age, size and complexity, as a candidate for OTE and that the decision would be taken at the end of the surgery on individual case to case basis, by strictly following set physiological criteria13.

PLANNING OF A NEW PERIOPERATIVE APPROACH More than 20,000 pediatric cardiac surgical cases had been successfully managed by conventional postoperative care including routine MV following surgery over an 11year period in our center. Although supported by encouraging data from the literature, bringing such a major change in a very busy clinical practice required consensus among the members of all involved subspecialties: cardiac surgeons, cardiologists, cardiac anesthesiologists, perfusionists, nurses and physiotherapists. In a multidisciplinary meeting, anesthetic plan, surgical goals, perfusion strategy, modalities of intraoperative assessment (with identification of potential contraindications for OTE, described later), postoperative monitoring and sedation protocols were presented, discussed, and finalized. Consensus was achieved not to include patients, who were mechanically ventilated preoperatively and in whom caudal analgesia was contraindicated due to: 1) anatomical abnormalities of sacrum or neural tube defects, 2) an international normalized ratio (INR) of more than 1.5. Institutional Review Board approved this plan13.

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METHODOLOGY

1) INTRAOPERATIVE PERIOD The detailed anesthetic technique followed standard of care procedures and

is

described elsewhere17. The proposition was to limit the anesthetic factors that delay extubation e.g. high dose narcotic use, postoperative pain, hypothermia, fluid overload and hemodynamic instability. We used a combination of opioid sparing technique (limiting fentanyl to maximum of 5 mcg/kg) during surgery along with a muscle relaxant and an inhalational agent, either isoflurane or sevoflurane depending on availability, in a dose of 1-1.5 MAC during open-heart surgery including cardiopulmonary bypass (CPB). Perioperative pain relief relied on the use of neuraxial block, known to provide excellent analgesia and additional blunting of stress response during perioperative period. We administered a mixture of preservative-free morphine (100 mcg/kg) and dexmedetomidine (1 mcg/kg), diluted in normal saline solution to 1 ml/kg, in a single shot injection with 22-24g needle into the

caudal

epidural

space7,14-20.

A

pediatric

multiplane

trans-esophageal

echocardiography (TEE) probe (Philips ultrasound, Bothell, WA, USA) was inserted for intraoperative monitoring and evaluation of the surgical repair in the operating room. Hypothermia was prevented with the help of a water blanket connected to the heater-cooler unit. Furthermore, the head and limbs were preventively covered with cotton pads and warm air was blown under the surgical drapes. Avoidance of an excessive increase in body-water content was achieved by miniaturization of the circuit, reduction of prime volume, a constant hematocrit target during cardiopulmonary bypass (CPB) at ≥ 25-30% and use of conventional (CUF) and modified ultrafiltration (MUF)21-23. An important task for the perfusionist was the

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meticulous monitoring of systemic venous drainage, especially of the inferior vena cava, to prevent critical reduction of pump flow and, ultimately, fluid retention and its further aggravation by unwanted volume additions. CUF and MUF were set to remove a volume of 80-140 ml/kg and 10-25 ml/kg, respectively. The goal of the surgeon was to ensure good corrective/palliative surgical result without any residual defect and with a good surgical hemostasis. In the case of identified correctable residual lesions after TEE assessment, the surgeon would address them in the same surgical session, with no hesitation to undertake additional periods of CPB and aortic cross-clamping, if necessry.

At the end of the operation, OTE was pursued in all patients provided the absence of any of the following conditions. First, the sternum left open. Second, an arterial oxygen tension (PaO2) less than 80 mm Hg in patients who received total correction and 55 mm Hg in those who underwent palliative procedure, in both cases with an inspired oxygen fraction of 0.50 and arterial carbon dioxide tension (PaCO2) more than 55 mm Hg. Third, an unsatisfactory hemostasis requiring transfusion of packed red blood cells more than 20% of blood volume during the post-bypass period. Fourth, the presence of hemodynamic instability requiring more than 7.5 mcg/kg/min of dobutamine and more than 0.075 mcg/kg/min of adrenaline ( equivalent to inotrope score of more than 15). Fifth, any other surgical concern due to patient factors, such as suboptimal native morphology, for which the surgeon felt the need for further observation in the intensive care unit for some time13. In the absence of the above-mentioned factors, if the patient was hemodynamically stable, neuromuscular blockade was reversed with neostigmine 0.05mg/kg and glycopyrrolate 0.005mg/kg. A good ventilatory effort of the patient was confirmed

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based on a respiratory rate less than 30/minute, tidal volume 8-10 ml/kg and absence of accessory respiratory muscle recruitment along with satisfactory gas exchange. At that point, the endotracheal tube was removed and oxygen was administered via nasal cannula. If any patient was agitated, intravenous midazolam 0.1 mg/kg was administered. Patients who were not extubated in the operating room due to concerns like bleeding, pulmonary dysfunction or cardiac dysfunction were shifted to ICU and placed on a regime of sedation with dexmedetomidine(0.5 mcg/kg/hr) and fentanyl (1mcg/kg/hr) and occasionally paralysis. These patients were, then, extubated by the intensivists according to standard extubation criteria,. The factor responsible for deferring extubation in the operating room was documented.

2) POSTOPERATIVE PERIOD In the postoperative period, the goal of the intensivist was to ensure hemodynamic and arterial blood gas monitoring, sedation and analgesia. Sedatives and analgesics were administered as intravenous infusion of dexmedetomidine and/or fentanyl titrated to to maintain a FLACC (face, legs, activity, crying, consolation) score of less than 2. In the ICU, every patient underwent a baseline transthoracic echocardiography for assessment of surgical repair, cardiac function, diaphragm movement and pulmonary artery pressure ( especially in the cases of pulmonary artery hypertension). Transthoracic echocardiography would be repeated within 6-8 hours for reassessment. In the event of an echocardiographic evidence of deteriorating cardiac function, the intensivist would be liberal to re-intubate even if hemodynamic and biochemical parameters appeared stable. The staff nurse was fully aware of the protocol and his/her goal was to ensure continuous monitoring of the vital signs. The respiratory

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physiotherapist‟s role was to ensure a clear airway by gentle suctioning of nasopharynx and oropharynx every 2 hours and to start chest physiotherapy as early as possible, after discussion with the intensivist. In all patients with reported pulmonary artery hypertension (PAH), mean pulmonary artery pressure (MPAP) was compared with mean systemic arterial pressure (MSAP) before and after the surgical repair. We considered 3 level of PAH severity: patients with MPAP/MSAP ratio less than 0.4 as mild, MPAP/MSAP between 0.4 - 0.7 as moderate and MPAP/MSAP more than 0.7 as severe PAH. Patients with MPAP/MSAP more than 0.7 would be given oral sildenafil 0.5-1.0 milligram/ kilogram (mg/kg) via a nasogastric tube in the ICU. In addition, transthoracic echocardiography would be done to assess pulmonary artery pressure, right ventricular function, left ventricular function and interventricular septum.

RESULTS OF THE INITIAL EXPERIENCE In the initial series of 1000 consecutive patients operated on in an 8-month period (2012-13), OTE was successfully accomplished in over 85% of the cases (n = 871/1000), including: 40% of the neonates (≤ 30 days, n = 8/20), 81% of the infants (1-12 months, n = 264/327), 92% of the children (1-18 years, n = 599/653). Hospital mortality (1%) and early re-intubation (5%) rates were unrelated to OTE17. Duration of intensive care unit (ICU) stay decreased from 5.4±2.3 to 2.6±1.8 days13.

ADAPTATIONS AFTER INITIAL EXPERIENCE Performing OTE was a major change in our clinical practice and every effort was made to accomplish it successfully. Few initial concerns that we had come across

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while handling the patients with OTE in the immediate post-operative period were addressed by the following adaptions in the ICU: - Tolerating

PaCO2 levels upto 50-60 mmHg, a common finding after caudal

morphine injection, as it usually settled in 1-2 hours. - Keeping the patients warm to avoid bronchospasm. - Minimal/no handling of the patients in the initial half-an-hour to avoid hemodynamic instability and breath holding especially in neonates and infants, as they are very sensitive to touch. - Performing transthoracic echocardiography as early as possible to provide a baseline for cardiac status and repeating the assessment after 6 hours or earlier in the case of any hemodynamic compromise. - Titrating sedation on an individual basis. - Starting early feeding (after 4-6 hours), initially with clear fluids and gradually stepping up to milk and solids, depending on patient‟s acceptance. Most of the awake, extubated, patients used to cry because of hunger which was suspected as there were no objective signs of pain. In fact, bigger children used to deny having pain and to explicitly ask for food and infants used to pacify after feeding.

REPRODUCIBILITY IN DIFFERENT HOSPITAL SETTINGS

After the initial series of 1000 patients (and of additional 3000 patients, whose data were not collected for study purposes) undergoing OTE in our original organization, the next challenge was the reproducibility of such strategy. Therefore, in the past three years, with the addition of new members, we moved forward to apply the same approach in other institutions. Satisfactorily, we were indeed able to replicate our

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OTE strategy with consistent results in our new hospital setting as well in other 6 different hospitals, during charity mission trips (Table 1). Our current extubation rate in the operating theatre is now, in fact, up to 95% with substantial reduction of postoperative ICU stay. In the post-operative period, our re-intubation rate is 1.25%, likewise others‟ experience2,28. CONTINUATION AND PROGRESSIVE STEPS Similar reports of OTE in pediatric cardiac surgery in developed countries have appeared24-27. With time our protocolized approach has substantially remained the same, i.e. OTE based on individual assessment and intraoperative decision, with only a few changes: cisatracurium instead of pancuronium and Del Nido cardioplegia instead of St. Thomas cardioplegia, milrinone instead of dobutamine, sevoflurane instead of isoflurane and acceptance of PaO2 of 40 mm Hg instead of 55 mm Hg for patients undergoing palliative procedures. With this practice and increasing confidence of each team component, we have been able to achieve OTE in several patients in whom this approach would be considered relatively contraindicated according to the standard management criteria: For example high Aristotle score (including our only 2 Norwood patients)28, low weight, long CPB and aortic crossclamp times, mechanical ventilation-dependence prior to surgery. For example, we were able to extubate 88% of patients in our cohort with long CPB ( more than 180 minutes) ( Table 4).

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DISCUSSION KEY POINTS WHICH LED TO SUCCESS OF OTE

Our endeavor to produce consistent results in performing OTE was thought provoking. Many questions needed to be addressed, such as: Is it really necessary to go out of the comfort zone and extubate the patients in the operating room when this can be easily done in the ICU in the coming hours? Or are we compromising on the patient safety especially after a major surgery with anticipated hemodynamic fluctuations? Or are we really saving any time or money? and many more. Change is never accepted easily, but an open mind to a different way of thinking and the passion of the entire team in pursuing the best for our patients has been the most powerful tool to accomplish an epochal change in our practice. In a recent multicenter international survey1, both from European and non-European countries, 76% respondents practiced on table extubation with 50% regularly performing on table extubation in different proportions (1% to 51%), and 77% made decision on case to case basis. The safety of OTE was perceived as excellent by 70% of the respondents and none of the same respondents had stopped OTE for safety reasons. The extra operating room time is another reason for rejecting OTE by many as it increases cost and slows turnover intervals but, with increasing experience and confidence, this time can be reduced significantly minimizing its impact on cost and turnover time. We spend 5-10 minutes extra in the operating room whereas an interval as short as 2 minutes has been reported by Shinkawa et al24. The practice of OTE varies among institutions, depending on physician preferences, comfort of the entire team and other logistic considerations. Bates et al29 showed that

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the degree of change after implementation varies in magnitude from institution to institution. After implementation the sustainability of the change in strategy also varies among different places30. So the success of OTE is purely dependent on individual group decision and implementation of programmatic changes.

Intraoperative use of short-acting opioids and other drugs is vital for the practice of OTE but simultaneous profound steady analgesia, in addition to balanced anesthesia, is of utmost importance during and after surgery. In our experience, caudal analgesia ensures an excellent, long lasting and steady pain control without respiratory depression and hemodynamic instability, especially in neonates and infants as described by different authors. Systemic narcotic analgesia may be equally effective, but chances of postoperative respiratory depression are much higher with narcotics. The addition of dexmedetomidine31 provides sedation without respiratory depression both intraoperatively and postoperatively. The use of dexmedetomidine is growing with documented evidence of reduced mortality with its use32. We limited the dose of opioids and used shorter acting drugs, with the constraint of choice of drugs due to cost or availability especially during charity missions. The other issues that can potentially deter anesthesiologists from OTE are impairment of pulmonary function and hypothermia. Impairment of pulmonary function was minimized by removing the extra fluid with the help of CUF and MUF. Hypothermia was avoided by warm blanket, wrapping the patients with cotton pad and blowing warm air under the drapes. Surgically, every effort is made to achieve a complete correction, whether anatomical or physiological, or a well-balanced palliation; in essence, surgery should avoid any significant residual lesion and assure a meticulous hemostasis to reduce the need for

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blood transfusion. Before aortic decannulation, intraoperative trans-esophageal echocardiographic (TEE) assessment is routinely carried out to assess the adequacy of complete surgical repair and ventricular function. Presence of any residual defects should be addressed in the same surgical session. Cardiopulmonary bypass is a known risk factor for several complications, e.g. capillary leakage, interstitial oedema and multi-organ damage. These deleterious effects, commonly related to bypass duration, hemodilution and systemic inflammatory response syndrome, are nowadays mitigated by virtue of correct application of technological advances like miniaturization of the circuit, conventional and/or modified ultrafiltration to name a few. We have observed that even a very long duration of cardiopulmonary bypass, with or without a period of deep hypothermic circulatory arrest, does not limit the suitability of the patient for OTE, as long as the homeostasis is maintained. Traditional risk factors, e.g. very young age, low body weight and complex anatomical diagnosis, should not be the limiting factors for adopting OTE approach, although they, admittedly, more easily lead to perioperative physiological derangement. Many recent studies have confirmed that these factors are not limiting the physicians from doing OTE3,4,7,8, 24-27. The key point for managing such patients is to shift the focus from strictly observing “putative” risk categories (electively staging the postoperative phases of treatment) to taking action based on the actual clinical status (after proactively trying to prevent any physiological derangement). Paradoxically, a baby with transposition undergoing a technically successful arterial switch operation may be a good candidate for OTE, whereas, a patient with a simple atrial septal defect may fail extubation for a number of unexpected intraoperative events.

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Even pulmonary hypertension should not be considered an absolute contraindication for OTE. Postoperative pain and, particularly, endotracheal tube suctioning are the main causes for postoperative pulmonary hypertensive crises in predisposed patients8. As we pointed out earlier, a successful OTE strategy includes a multimodal approach to adequate pain control, and in the absence of an endotracheal tube, frequent suctioning of the trachea and bronchial tree is not required. In our study, we accepted mild hypercapnia in the immediate postoperative period despite a theoretical risk of aggravating pulmonary hypertension and right ventricular dysfunction. We observed that this short-lasting hypercapnia was tolerated very well by the patients as none of them showed any sign of worsening right ventricular function ( as assessed by serial transthoracic echocardiography), desaturation, bradycardia or reintubation. Similar observation was made by Kloth et al33.

Risk of reintubation after OTE is always a major concern but different studies2,24 have shown reduced incidence of reitubation in the OTE group. Similarly with experience our reintubation rate is now 1.25%. Contraindications to OTE, like inadequate gas exchange, bleeding, ventricular dysfunction requiring high inotropes and residual lesion, have also been identified. However, these are attributed to patient- or surgery-related factors, contingently raising concerns about post-operative clinical stability and all theoretically controllable13.

The limitation of our study is that it has no control group to prove its superiority. The initial study of 1000 patients, which was done in a short span of 8 months, had

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historical controls and it was persumed that the observed benefit were purely because of OTE as all the other management modalities had remained the same. Direct or indirect cost saving assessment was not calculated by us but cost saving has been documented by others5,34. After the initial study the practice of OTE has been routinely implemented Other few limitations in our study are: non-availability of data about the behavior of patients with different grades of pulmonary hypertension in response to hypercarbia and the trans-thoracic echocardiography findings. Though none of the patients had any adverse event it remains an important question for future clinical trials. Similarly data about serial blood gas measurements is missing though blood gases were monitored and managed according to standard ICU guidelines with the exception of hypercarbia( 50-60 mmHg) which lasted from 1- 2 hours without any adverse event. Another gap in the evidence is the practice of OTE in patients with long CPB. We experienced that the duration per se is not a contraindication for OTE as long as homeostasis is maintained and surgical repair is good. Our study opens many questions for future trials like large randomized trials at multicenter level with standardized technique to prove the superiority of OTE, impact of hypercarbia in patients with PAH and effect of duration of CPB on suitability for OTE.

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WHAT IS SO SPECIAL ABOUT IT TO MAKE OTE AS A ROUTINE PRACTICE ? Goals of the international quality improvement initiatives in pediatric cardiac surgery include the practice of fast tracking35. It may be a necessity especially during charity missions and in hospital setting with limited resources. Meeting OTE criteria at the end of the surgical procedure reflects a protocolized team-based approach involving each and every team member present in the operating room. It is an extremely reassuring experience to see a child already awake and spontaneously breathing in the immediate postoperative period, even after a complex cardiac operation. Complications related to mechanical ventilation are avoided. Though OTE patients need much more attention in the first 1-2 hours (till they stabilize) but the work load is much less as compared to the patient on ventilator. All that is required of doctors and nurses is monitoring the patients with the least stimulation and intervention. Postoperative ICU and hospital stays are reduced, leading to more efficient utilization of resources13 and possibly reduction of costs. This practice can be implemented if all the team members of perioperative care collectively plan, assess and manage the patients36.

CONCLUSIONS In our experience in the developing world, OTE has been a safe and efficient way of managing pediatric cardiac surgical patients with evident clinical benefits and better use of resources. This treatment model might be considered by other groups, provided the acceptance by all team members, for resource-sparing purposes and clinical benefits for the patients, ultimately signifying a marker of quality improvement.

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REFERENCES 1. Akhtar MI, Momeni M, Szekely A, et al. Multicenter international survey onthe clinical practice of ultra-fast track anesthesia with on table extubation inpediatric congenital cardiac surgery. J Cardiothorac Vasc Anesth 2019;33:406-415. 2. Harris KC, Holowachuk S, Gandhi SK, et al. Should early extubation be the goal for children after congenital cardiac surgery? J Thorac Cardiovasc Surg 2014;148:2642-8. 3. Heinle JS, Diaz LK, Fox LS. Early extubation after cardiac operations in neonates and young infants. J Thorac Cardiovasc Surg 1997;114:413-8. 4. Preisman S, Lembersky H, , Keidan I, et al. A randomized trial of outcomes of anesthetic management directed to very early extubation after cardiac surgery in children. J Cardiothorac Vasc Anesth 2009; 23:348-57. 5. Lawrence EJ, Nguyen K, Morris SA, Hollinger I, et al: Economic and safety implications of introducing fast tracking in congenital heart surgery. Circ Cardiovasc Qual Outcomes 2013;6:201-7. 6. Barash PG, Lescovich F, Katz JD, et al. Early extubation following pediatric cardiothoracic operation: a viable alternative. The Annals of thoracic surgery 1980;29:228-33. 7. Mittnacht AJ, Thanjan M, , Hossain S, et al. Extubation in the operating room after congenital heart surgery in children. J Thorac Cardiovasc Surg 2008; 136:88-93. 8. Vida VL, Leon-Wyss J, Castaneda AR, et al. Pulmonary artery hypertension: is it really a contraindicating factor for early extubation in children after cardiac surgery? The Annals of thoracic surgery 2006;81:1460-5. 9. Vricella LA, Dearani JA, Gundry SR, et al: Ultra fast track in elective congenital cardiac surgery. Ann Thorac Surg 2000;69:865-871.

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10. Kloth RL, Baum VC: Very early extubation in children after cardiac surgery. Crit Care Med 2002;30:787-791. 11. Neirotti RA, Jones D, Hackbarth R, et al: Early extubation in congenital heart surgery. Heart Lung Circ 2002;11:157-161. 12. Davis S, Worley S, Mee RB, et al: Factors associated with early extubation after cardiac surgery in young children. Pediatr Crit Care Med 2004;5:63-68. 13. Garg R, Rao S, John C, et al. Extubation in the operating room after cardiac surgery in children: a prospective observational study with multidisciplinary coordinated approach. Journal of cardiothoracic and vascular anesthesia 2014;28:47987. 14. Rosen KR, Rosen DA. Caudal epidural morphine for control of pain following open heart surgery in children. Anesthesiology 1989;70:418-21. 15. Leyvi G, Taylor DG, Reith E, Stock A, Crooke G, Wasnick JD. Caudal anesthesia in pediatric cardiac surgery: Does it affect outcome? J Cardiothorac Vasc Anesth 2005;19:734-8. 16. Rojas-Pιrez E, Castillo-Zamora C, Nava-Ocampo AA. A randomized trial of caudal block with bupivacaine 4 mg/kg (1.8 ml/kg) plus morphine (150 mcg/kg) vs general anaesthesia with fentanyl for cardiac surgery. Paediatr Anaesth 2003;13:311-7 17. Tenenbein PK, Debrouwere R, Maguire D, Duke PC, Muirhead B, Enns J, et al. Thoracic epidural analgesia improves pulmonary function in patients undergoing cardiac surgery. Can J Anaesth 2008;55:344-50. 18. Chrysostomou C, Di Filippo S, Manrique AM, Schmitt CG, Orr RA, Casta A, et al. Use of dexmedetomidine in children after cardiac and thoracic surgery. Pediatr Crit Care Med 2006;7:126-31.

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19. Easley RB, Tobias JD. Pro: Dexmedetomidine should be used for infants and children undergoing cardiac surgery. J Cardiothorac Vasc Anesth 2008;22:147-51. 20. Nasr DA, Abdelhamid HM. The efficacy of caudal dexmedetomidine on stress response and postoperative pain in pediatric cardiac surgery. Annals Card Anaesth 2013;16:109-14. 21. Sever K, Tansel T, Basaran M, Kafali E, Ugurlucan M, Ali Sayin O, et al. The benefits of continuous ultrafiltration in pediatric cardiac surgery. Scand Cardiovasc J 2004;38:307-11. 22. Mahmoud AB, Burhani MS, Hannef AA, Jamjoom AA, Al-Githmi IS, Baslaim GM. Effect of modified ultrafiltration on pulmonary function after cardiopulmonary bypass. Chest 2005;128:3447-53. 23. Kameyama T, Ando F, Okamoto F, Hanada M, Yamanaka K, Sasahashi N, et al. The effect of modified ultrafiltration in pediatric open heart surgery. Ann Thorac Cardiovasc Surg 2000;6:19-26. 24. Shinkawa T, Tang X, Gossett JM, et al. Incidence of immediate extubation after pediatric cardiac surgery and predictors for reintubation.World J Pediatr Congenit Heart Surg 2018; 9: 529-36. 25. Varghese J, Kutty S, Hammel JM, et al. Preoperative and intraoperative predictive factors of immediate extubation after neonatal cardiac surgery. Ann Thorac Surg 2016;102:1588-95.

26. Varghese J, Kutty S, Hammel JM, et al. Five-year experience with immediate extubation after arterial switch operations for transposition of great arteries. Eur J Cardiothorac Surg 2017;51:728-34.

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27. Varghese J, Hammel JM, Kutty S, et al. Outcomes related to immediate extubation after stage 1 Norwood palliation for hypoplastic left heart syndrome. J Thorac Cardiovasc Surg 2019;157: 1591-98

28. Garg R, Thareen JK, Di Donato RM, et al. On-table extubation after Norwood operation. J Cardiothorac Vasc Anesth 2019;33:2760-62.

29. Bates KE, Mahle WT, Bush L, et al. Variation in implementation and outcomes of early extubation practices after infant cardiac surgery. Ann Thorac Surg 2019; 107:1434-1440.

30. Gaies M, Pasquali SK, Nicolson SC, et al. Sustainability of infant cardiac surgery early extubation practices after implementation and study . Ann Thorac Surg 2019; 107:1427-33.

31. Kiski D, Malec E, Schmidt C. Use of dexmedetomidine in pediatric cardiac anesthesia. Curr Opin Anaesthesiol 2019; 32:334-42.

32. Schwartz LI, Twite M, Gulack B, et al. The perioperative use of dexmedetomidine in pediatric patients with congenital heart disease: An analysis from the Congenital Cardiac Anesthesia Society-Society of Thoracic Sur- geons Congenital Heart Disease database. Anesth Analg 2016;123:715–21.

33. Kloth RL, Baum VC. Very early extubation in children after cardiac surgery. Crit Care Med 2002; 30:787-91.

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34. Holowachuk S, Zhang W, Gandhi SK, et al. Cost savings analysis of early extubation following congenital heart surgery. Pediatr Cardiol 2019; 40:138-146.

35. Hickey PA, Connor JA, Cherian KM, et al. International quality improvement initiatives. Cardiol Young. 2017;27(S6):S61-S68

36. Richards M, Latham G, Ross F,Eisses, et al. To OTE or not to OTE: That is the question-current international trends of on the table extubation after pediatric cardiac surgery. J Cardiothorac Vasc Anesth 2019; 33:416-17.

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Table 1: Recent clinical experience with OTE in different hospital settings

Setting/ Hospital

Total No.

AJCH

174

Charity missions (Sudan, Mauritania, Tanzania, Tajikistan

66

Age distribution/ Number Neonates/35 Infants/ 81 Children/ 58

Infants/6 Children/60

Extubated/ Total (%)

Reintubated/ Not extubated/ Reason Reason

26/35 (74.2) 75/81 (92.5) 57/58 (98.2)

1 PE 1 bleeding Nil

6/6 (100) 60/60 (100)

1 bleeding Nil

9: (7 OC, 2 preop MV) 6: 4 OC, 1 LV dsfx, 1 desat 1 LV dsfx 0 0

Abbreviations: AJCH – Al Jalila Children‟s Hospital, PE- pulmonary edema, OCopen chest, MV – mechanical ventilation, LV dsfx - left ventricular dysfunction, desat - desaturation

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Table 2. Details of procedures performed recently along with percentage of patients extubated on-table Procedure

Number of patients extubated on-table/ total patients

Percentage(% ) of patients extubated on-table 95.1 100 100 75 85.7 100 87.5 50 100 100 75 50 100 75 100 100 100 100 100 100 100 50

Mortality among on-table extubated/not ontable extubated

Total correction for TOF 59/62 0/1 VSD closure 56/56 0/0 ASD closure 25/25 0/0 ASO 9/12 0/2 AVCD repair 12/14 0/1 Partial AVCD repair 7/7 0/0 TAPVC repair 7/8 0/0 Truncus arteriosus repair 1/2 0/0 Rastelli procedure 1/1 0/0 Fontan 2/2 0/0 Central shunt 3/4 0/0 B-T shunt 1/2 1/0 Bi-directionalGlenn shunt 1/1 0/0 PA banding 3/4 0/1 RVOT reconstruction 5/5 0/0 Supraaortic stenosis repair 2/2 0/0 PDA ligation 7/7 0/0 Coarctation of aorta repair 12/12 0/0 Norwood procedure 2/2 0/0 Ross procedure 1/1 0/0 Nikaidoh procedure 1/1 0/0 VSD closure and coarctation 2/4 0/0 of aorta repair VSD closure and aortic 1/1 100 0/0 valve repair Bi-directional Glenn and 1/1 100 1/0 tricuspid valve replacement HOCM 0/1 0 0/0 Miscellaneous 3/3 100 0/0 Total 224/240 93.3 2/5 Abbreviations: TOF- tetralogy of Fallot, VSD-ventricular septal defect, ASD-atrial septal defect, ASO-arterial switch operation, AVCD-atrio-ventricular canal defect, TAPVC-total anomalous pulmonary venous connection, B-T- Blalock-taussig, PApulmonary artery, RVOT-right ventricular outflow tract, PDA-patent ductus arteriosus, HOCM- hypertrophic obstructive cardiomyopathy

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Table 3 Details of high risk category of patients High risk category Number of patients extubated on-table/ total patients(percentage) TAPVC, age <1year, Severe PAH 3/3(100%) AVCD with Down syndrome, severe PAH AVCD without Down syndrome, severe PAH VSD and aortic valve repair

11/13 (84.6%)

Rastelli procedure

1/1 (100%)

Nikaidoh procedure

1/1 (100%)

Ross procedure

1/1 (100%)

Norwood procedure

2/2

ASO

9/12 (75%)

Truncus arteriosus repair

1/2 (50%)

1/1 (100) 1/1 (100%)

Reintubation/mortality

No reintubation/ no mortality No reintubation/ 1 patient died of LCOS No reintubation/ no mortality No reintubation/ no mortality No reintubation/ no mortality No reintubation/ no mortality No reintubation/ no mortality No reintubation/ no mortality No reintubations/ 2 mortality

No reintubations ,no mortality Abbreviations: TAPVC-total anomalous pulmonary venous connection, PAHpulmonary artery hypertension, AVCD-atrio-ventricular canal defect, LCOS- low cardiac output syndrome, VSD-ventricular septal defect, TOF- tetralogy of Fallot, ASO- arterial switch operation

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Table 4. Details of patients with long CPB duration Duration of Age-wise distribution of Reason for not CPB patients extubating ( Minutes) Total/ extubated on-table 180-300 Neonates 10/8 Open chest 2

Total/ extubated on-table(%) 48/45(93.7)

Infants

300-400

Children 13/13 Neonates 2/2

Open chest (PH) 1 Nil Nil

Infants

Nil

Children

>400

25/24

3/3 2/1

Neonates 3/2

7/6(85.7)

Ventricular dysfunction due to multiple VSD closure Open chest 8/5(62.5)

Infants

4/2

ECMO ECMO Children 1/1 Nil Abbreviations: CPB-cardiopulmonary bypass, PH-pulmonary hypertension, VSDventricular septal defect, ECMO- extracorporeal membrane oxygenation

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