Spontaneous respiration during intravenous anesthesia in children.Curr Opin Anaesthesiol. 2009;22:383-387. [PMID: 19434785 DOI: 10.1097/aco.0b013e328329730c]

Anesthetic technique for awake artery malformation clipping with motor evoked potential and somatosensory evoked potential: A case report

BACKGROUND

Awake craniotomy has been widely used for tumor resection, epilepsy surgery, deep brain stimulation, and carotid endarterectomy. The report on awake artery malformation clipping is rare, especially for anesthesia management.

CASE SUMMARY

A 62-year-old female diagnosed with malformation of anterior cerebral artery at the right side. We clipped the artery malformation with intraoperative neuromonitoring (IONM) in awake craniotomy. Spontaneous respiration was maintained throughout the procedure by nasopharyngeal airway during the surgery successfully.

CONCLUSION

The technique of monitoring anesthesia care can be performed successfully for the patient with IONM.

Volatiles or TIVA: Which is the standard of care for pediatric airway procedures? A pro-con discussion

Anesthesia for pediatric airway procedures constitutes a true art form that requires training and experience. Communication between anesthetist and surgeon to establish procedure goals is essential in determining the most appropriate anesthetic management. But does the mode of anesthesia have an impact? Traditionally, inhalational anesthesia was the most common anesthesia technique used during airway surgery. Introduction of agents used for total intravenous anesthesia (TIVA) such as propofol, short-acting opioids, midazolam, and dexmedetomidine has driven change in practice. Ongoing debates abound as to the advantages and disadvantages of volatile-based anesthesia versus TIVA. This pro-con discussion examines both volatiles and TIVA, from the perspective of effectiveness, safety, cost, and environmental impact, in an endeavor to justify which technique is the best specifically for pediatric airway procedures.

Management of anesthesia and complications in children with Tracheobronchial Foreign Body Aspiration

OBJECTIVES

Delayed diagnosis and treatment of tracheobronchial foreign body aspiration (FBA) in children may lead to morbidity and mortality. Our objective was to evaluate the anesthetic management, peri- and post-operative complications, and predisposing factors for postoperative intensive care unit (ICU) admission in children undergoing rigid bronchoscopy due to tracheobronchial FBA.

METHODS

This retrospective study included 81 children who underwent rigid bronchoscopy between January 2010 to July 2018 at Inonu University, Department of Pediatric Surgery, Turkey. Data regarding demographic characteristics, anesthetic management, length of ICU and hospital stays, and peri- and post-operative complications were retrieved from the hospital database.

RESULTS

The patients included 54 (66.7%) boys and 27 (33.3%) girls with a mean age of 29.6 ± 31.2 months. The most common presenting symptom was the suspicion of FBA, followed by acute-onset cough, cyanosis, wheezing and respiratory distress. Mean duration of anesthesia was 44.40 ± 14.72 min. Of the 81 patients, 18 (22.2%) were transferred to ICU and 63 (77.8%) patients were transferred to the ward postoperatively. Of the patients transferred to the ICU, 5 of them required mechanical ventilation. Some peri and postoperative complications, desaturation (n=16; 19.7%; p=0.001), mucosal bleeding (n=6; 7.4%; p=0.02), laryngeal edema (n=11; 13.6%; p<0.001), laryngospasm (n=13; 16.3%; p<0.001), were affected the frequency of intensive care transfer.

CONCLUSION

Bronchoscopy with general anesthesia remains the golden standard for the management of tracheobronchial FBA. In such patients, a combination consisting of a detailed preoperative clinical evaluation of the patient, selection of short-acting anesthetic agents with minimal side effects for the induction and maintenance of anesthesia, and the administration of controlled ventilation can be recommended. Additionally, early diagnosis of peri- and post-operative complications, prediction of postoperative ICU requirement, and a close cooperation of anesthesiologists and surgeons are highly important.

Total intravenous anesthesia will supercede inhalational anesthesia in pediatric anesthetic practice

Inhalational anesthesia has dominated the practice of pediatric anesthesia. However, as the introduction of agents such as propofol, short-acting opioids, midazolam, and dexmedetomidine a monumental change has occurred. With increasing use, the overwhelming advantages of total intravenous anesthesia (TIVA) have emerged and driven change in practice. These advantages, outlined in this review, will justify why TIVA will supercede inhalational anesthesia in future pediatric anesthetic practice.

A retrospective study of anesthesia during rigid bronchoscopy for airway foreign body removal in children: propofol and sevoflurane with spontaneous ventilation

BACKGROUND

Tracheobronchial foreign body aspiration is a significant cause of childhood morbidity and mortality. We analyzed our experience in management of aspirated foreign bodies, including methods of anesthesia used, over a 4-year period.

METHODS

We retrospectively reviewed the records of tracheobronchial foreign body removal by rigid bronchoscopy with spontaneous ventilation in 435 children. All patients had received initial anesthesia with inhaled sevoflurane. One hundred and ninety-seven patients (Group PropRemi) then received intravenous propofol and remifentanyl for maintenance of anesthesia; the remaining 238 patients (Group PropSevo) received propofol and sevoflurane.

RESULTS

Tracheobronchial foreign body was found in 405 children (93.1%) and successfully removed from 402 (99.3%) children. Among three patients who failed bronchoscopy, one child suffered cardiac arrest and died during the bronchoscopy, and two required subsequent tracheotomy for foreign body removal. Adverse effects (intraoperative coughing, breath holding, body movement, bronchospasm, and laryngospasm) were significantly more frequent in Group PropRemi than in Group PropSevo. No complications such as bleeding, pneumothorax, pneumomediastinum, or the need for thoracotomy were encountered.

CONCLUSION

Sevoflurane induction followed by a combination of sevoflurane and continuous infusion of propofol resulted in fewer adverse events than sevoflurane induction followed by TIVA with propofol and remifentanyl during rigid bronchoscopy for airway foreign body removal in children with spontaneous ventilation.

[Is there an appropriate bispectral index for upper gastrointestinal endoscopy in spontaneous breathing in the pediatric patient?]

OBJECTIVE

The bispectral index (BIS) values that predict appropriate anesthetic level to perform an upper gastrointestinal endoscopy in spontaneous breathing are not well established in Pediatrics. The objective of this study is to determine whether it is possible to find an appropriate, less profound, BIS level in the pediatric patient that would enable an upper gastrointestinal endoscopy (UGE) to be performed in spontaneous breathing without causing gag reflex or motor response.

MATERIAL AND METHOD

A prospective study was designed and included 61 patients from 12-167 months old, and an ASAI-II who needed a diagnostic UGE. The study was conducted from October 2011 to March 2013.

INTERVENTION

UGE performed with an anesthetic protocol using propofol. The vital signs measured were heart and respiratory rate, pulse oximetry, non-invasive blood pressure. The sedation level score (Ramsay scale) and BIS values were also measured. The first attempt was performed at BIS level 60-69, and this was not feasible, then the anesthetic was deepened and a second attempt made at BIS level 50-59. If this was still not possible a deeper anesthetic level was then achieved and a third attempt made at BIS level 45-49. Variables of interest were: effective BIS level (eBIS), BIS level at which UGE was performed without gag reflex or motor response; propofol total dose (mgkg(-1)), induction time (time from onset of sedation to effective start of UGE). A logistic regression analysis was performed to obtain an equation to estimate the possibility of UGE success.

RESULTS

The distribution of the patient was: male 40%, female 60%, with 11 (18%) patients under 36 months. The statistical values are expressed as mean and standard deviation, with following results; age (months): 95.9±45.86; weight (kg): 30.5±14.68; effective BIS: 56.41±4.63; induction time (minutes): 11.07±2.69; total propofol dose (per kg): 4.86±1.21. An additional intra-procedure propofol bolus was given in 38 patients (62%), with 7/38 of them (18%) due to movement, and 31/38 (82%) due to BIS level increase. No statistical differences were found in effective BIS level between older and younger patients.

CONCLUSIONS

According to the results, BIS levels below 59 predict UGE success, with 72.13% sensitivity and 88.06% specificity in the pediatric population studied.

Dexmedetomidine vs remifentanil intravenous anaesthesia and spontaneous ventilation for airway foreign body removal in children

BACKGROUND

To compare the safety and efficacy of dexmedetomidine/propofol (DP)-total i.v. anaesthesia (TIVA) vs remifentanil/propofol (RP)-TIVA, both with spontaneous breathing, during airway foreign body (FB) removal in children.

METHODS

Seventy-seven children undergoing rigid bronchoscopy for FB removal were randomly allocated to receive either RP-TIVA and spontaneous ventilation (Group RP, n=38) or DP-TIVA and spontaneous ventilation (Group DP, n=39). Heart rate, arterial pressure, pulse oxygen saturation (Sp(O2)), respiratory rate, end-tidal CO2 (E'(CO2)), and induction time were recorded. Adverse events, the intervention for these events, and postoperative care duration were also assessed.

RESULTS

The mean induction times were comparable between the two groups (Group RP 12.2 min vs Group DP 13.1 min, P>0.05). At the end of the procedure, the mean (E'(CO2)) was higher in Group RP (Group RP 6.8 kPa vs Group DP 5.8 kPa, P<0.001), and respiratory rate was lower in Group RP (Group RP 20.4 vs Group DP 35.8, P<0.001). Additionally, the perioperative haemodynamic profile was more stable in Group DP than that in Group RP. The incidence rate of breath-holding and intervention were comparable between the two groups. In the post-anaesthesia care unit (PACU), no hypoxaemia was observed, and emergence time increased in Group DP (Group DP 65.1 min vs Group RP 23.8 min, P<0.0001). The incidence of cough in PACU was higher in Group RP (Group RP 55.3% vs Group DP 10.3%, P<0.0001).

CONCLUSIONS

Compared with RP-TIVA, DP-TIVA provided more stable respiratory and haemodynamic profiles, but required a longer recovery time. Clinical trial registration China Clinical Research Information Service, ChiCTR-TRC-13003018.

Preoperative evaluation of the patient with pulmonary disease

BACKGROUND AND OBJECTIVES

In daily clinical practice, pulmonary complications related to surgical procedure are common, increasing the morbidity and mortality of patients. Assessment of the risk of pulmonary complications is an important step in the preoperative evaluation. Thus, we review the most relevant aspects of preoperative assessment of the patient with lung disease.

CONTENT

Pulmonary risk stratification depends on clinical symptoms and patient's physical status. Age, preexisting respiratory diseases, nutritional status, and continued medical treatment are usually more important than additional tests. Pulmonary function tests are of great relevance when high abdominal or thoracic procedures are scheduled, particularly when lung resection are considered.

CONCLUSION

Understanding the perioperative evaluation of the potential risk for developing pulmonary complication allows the medical team to choose the adequate anesthetic technique and surgical and clinical care required by each patient, thereby reducing adverse respiratory outcomes.

Respiratory function during anesthesia: effects on gas exchange

Anaesthesia causes a respiratory impairment, whether the patient is breathing spontaneously or is ventilated mechanically. This impairment impedes the matching of alveolar ventilation and perfusion and thus the oxygenation of arterial blood. A triggering factor is loss of muscle tone that causes a fall in the resting lung volume, functional residual capacity. This fall promotes airway closure and gas adsorption, leading eventually to alveolar collapse, that is, atelectasis. The higher the oxygen concentration, the faster will the gas be adsorbed and the aleveoli collapse. Preoxygenation is a major cause of atelectasis and continuing use of high oxygen concentration maintains or increases the lung collapse, that typically is 10% or more of the lung tissue. It can exceed 25% to 40%. Perfusion of the atelectasis causes shunt and cyclic airway closure causes regions with low ventilation/perfusion ratios, that add to impaired oxygenation. Ventilation with positive end-expiratory pressure reduces the atelectasis but oxygenation need not improve, because of shift of blood flow down the lung to any remaining atelectatic tissue. Inflation of the lung to an airway pressure of 40 cmH2O recruits almost all collapsed lung and the lung remains open if ventilation is with moderate oxygen concentration (< 40%) but recollapses within a few minutes if ventilation is with 100% oxygen. Severe obesity increases the lung collapse and obstructive lung disease and one-lung anesthesia increase the mismatch of ventilation and perfusion. CO2 pneumoperitoneum increases atelectasis formation but not shunt, likely explained by enhanced hypoxic pulmonary vasoconstriction by CO2. Atelectasis may persist in the postoperative period and contribute to pneumonia.

Propofol-remifentanil intravenous anesthesia and spontaneous ventilation for airway foreign body removal in children with preoperative respiratory impairment

PURPOSE

To investigate the efficacy and safety of propofol-remifentanil total intravenous anesthesia (TIVA) and spontaneous ventilation for foreign body (FB) removal in pediatric patients with preoperative respiratory impairment.

METHODS

We carried out a prospective observational clinical study of FB removal using a rigid bronchoscope under propofol-remifentanil TIVA and spontaneous ventilation in 65 pediatric patients who presented with preoperative respiratory impairment. Heart rate, blood pressure, pulse oxygen saturation (SpO(2)), respiratory rate, endtidal CO(2) (ETCO(2))(ETCO2), induction time, and remifentanil rate were recorded. Adverse events, the intervention for these events, and the duration of postoperative care were also of interest.

RESULTS

Sixty children completed the study. The mean induction time was 12.3 min. During the procedure, the maximum remifentanil rate was 0.14 μg · kg(-1) · min(-1). Light breath holding occurred in 16 (26.7%) patients. No severe breath holding or body movements were observed. An SpO(2) below 90% occurred in 10 (16.7%) cases. No progressive desaturation was observed. The mean ETCO(2) at the end of the procedures was 7.91 KPa and returned to normal 5 min after the procedure. In the postanesthesia care unit (PACU), no hypoxemia was observed and the mean recovery time was 23.4 min. No laryngospasm, pneumothorax, or arrhythmias were observed.

CONCLUSION

Propofol-remifentanil TIVA and spontaneous ventilation are effective and safe techniques to manage anesthesia during airway FB removal in children with preoperative respiratory impairment.

Remifentanil, a different opioid: potential clinical applications and safety aspects

IMPORTANCE OF THE FIELD

Opioids play an important role in every aspect of modern anesthetic practice. Remifentanil is an ultra-short-acting opioid featuring a unique pharmacokinetic profile allowing clinical versatility and improved control of its action. In this review, we assess the pharmacology of remifentanil, its clinical uses as well as safety issues on its action on the major organ systems and in particular clinical settings.

AREAS COVERED IN THIS REVIEW

A synthesis of evidence from a MEDLINE search for articles from 1993 to 2009 for available up-to-date information on remifentanil and its current applications and safety profile.

WHAT THE READER WILL GAIN

A synopsis of the unique pharmacokinetic properties of remifentanil and its action on major organ systems will provide insight on the safe and effective use of the drug in a variety of clinical settings.

TAKE HOME MESSAGE

Remifentanil is a valuable opioid in the armamentarium of the clinician, providing great clinical flexibility and safety but vigilance is required to avoid pitfalls.