Preoperative apnea in a preterm infant after caudal block with ropivacaine and clonidine

Awake caudal anesthesia in ex-premature infants undergoing lower abdominal surgery: A narrative review

BACKGROUND AND OBJECTIVES

The aim of this narrative review is to evaluate the literature describing the use of caudal anesthetic-based techniques in premature and ex-premature infants undergoing lower abdominal surgery.

METHODS

All available literature from inception to August 2023 was retrieved according to Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines from Medline, PubMed, Embase, and the Cochrane Library. Two authors reviewed all references for eligibility, abstracted data, and appraised quality.

RESULTS

Of the 211 articles identified, 45 met our inclusion criteria yielding 1548 cases with awake caudal anesthesia. The review included 558 (36.0%) cases of awake caudal anesthesia, 837 cases (54.1%) of "awake" caudal anesthesia with sedation, and 153 cases (9.9%) of combined spinal caudal epidural anesthesia without sedation. The overall anesthetic failure rate was 7.2% (71.9:1000 caudals). Failure rates were highest for CSEA (13.7%, 7.7-18.4), intermediate for awake caudal (6.6%, 5.26-9.51), and lowest for sedated caudal anesthesia (5.85%, 4.48-7.82). The incidence (range) of perioperative apnea was highest for sedated caudal anesthesia (8.16, 0%-24%), intermediate for awake caudal (7.62%, 0%-60%), and lowest for CSEA (5.53%, 0%-14.3%). High spinal anesthesia occurred in 0.84%, or 8.35:1000 caudals overall. The incidence was highest in awake caudal anesthesia cases (1.97% or 19.7:1000 caudals), intermediate with caudal with sedation (1.07% or 10.7:1000 caudals), and lowest in CSEA (0.7% or 6.6:1000 caudals). Our review was confounded by incomplete data reporting and small sample sizes as most were case reports. There were no high-quality randomized controlled trials, and the eight single-center retrospective data reviews lacked sufficient data to perform meta-analysis.

CONCLUSIONS

There is insufficient evidence to validate or refute the benefits of the use of "awake" caudal anesthesia in premature and ex-premature infants. The high doses of local anesthetics used, the high failure rate, and the increased incidence of high spinal anesthesia would suggest that the techniques offer no real advantages over awake spinal anesthesia or general anesthesia with a regional block.

Ambulatory spinal anesthesia in infants ≤ six months of age: A retrospective review of outcomes and safety

PURPOSE

To review experience with outpatient spinal anesthesia (SA) from a single center in infants ≤6 months of age.

METHODS

Retrospective review of all SAs performed in the ambulatory setting in the outpatient surgery centers in infants ≤6 months of age from 2016 to 2020, focusing on success rate, adverse events, post-anesthesia care unit (PACU) times, and emergency department (ED) or urgent care (UC) returns within 7 days of the operation.

RESULTS

The study cohort included 175 SAs performed on 173 patients ≤6 months of age. One hundred and sixty-two patients (93%) were able to undergo their respective surgical procedures under SA without conversion to general anesthesia. One hundred and thirty-six patients (78%) did not require additional sedation or analgesic agents. The median time from entering the operating room until the start of surgical procedure was 17 min. One hundred and twenty-six patients (72%) were able to bypass Phase I of the PACU. One hundred and forty-seven patients (86%) were discharged in less than two hours postoperatively. Only one complication related to SA was noted. This was a patient who returned on postoperative day 2 with a possible CSF leak noted by ultrasound. After overnight hospital floor admission, he was discharged the next day after receiving intravenous fluids without further sequelae.

CONCLUSIONS

SA is a viable option for anesthetic care in infants ≤6 months of age presenting for outpatient surgery. Advantages included the ability to bypass PACU Phase I and facilitation of hospital discharge.

LEVEL OF EVIDENCE

IV. Retrospective cohort treatment study.

Regional anaesthesia in neonates, infants and children: an educational review

Prophylactic analgesia with local anaesthesia is widely used in children and has a good safety record. Performing regional blocks in anaesthetised children is a safe and generally accepted practice. When compared with adults, lower concentrations of local anaesthetics are sufficient in children; the onset of a block occurs more rapidly but the duration is usually shorter. Local anaesthetics have a greater volume of distribution, a lower clearance and a higher free (non-protein-bound) fraction. The recommended maximum dose has to be calculated for every individual. Peripheral blocks provide analgesia restricted to the site of surgery, and some of them have a very long duration of action. Abdominal wall blocks, such as transverse abdominis plane or ilio-inguinal nerve block, should be performed with the aid of ultrasound. Caudal anaesthesia is the single most important technique. Ropivacaine 0.2% or levobupivacaine 0.125 to 0.175% at roughly 1 ml  kg⁻¹ is adequate for most indications. Clonidine and morphine can be used to prolong the duration of analgesia. Ultrasound is not essential for performing caudal blocks, but it may be helpful in case of anomalies suspected at palpation and for teaching purposes. The use of paediatric epidural catheters will probably decline in the future because of the potential complications.

Caudal blocks

Caudal anesthesia is the single most important pediatric regional anesthetic technique. The technique is relatively easy to learn (1), has a remarkable safety record (2), and can be used for a large variety of procedures. The technique has been reviewed in the English (3) and French (4) literature, as well as in German guidelines (5) and in pediatric anesthesia textbooks (6).

One hundred times the intended dose of caudal clonidine in three pediatric patients

We report three sequential cases in which children received 100 times the intended dose of clonidine in their single shot caudals. Although all experienced excessive somnolence for up to 24 h, none had respiratory depression, oxygen desaturation, supplemental oxygen requirement, or hemodynamic instability. These cases suggest a large margin of safety exists for caudally administered clonidine in healthy children.

Regional anesthesia for postoperative pain control in children: focus on continuous central and perineural infusions

Regional anesthesia is widely employed for postoperative pain control in both adults and children. Central or perineural approaches can be performed as a bolus injection or as a continuous infusion of local anesthetics. However, bolus injections, even with the addition of adjuvants, are inadequate for prolonged surgery and long-term pain control. Continuous infusion remains the technique of choice when there is a prolonged operation or intense postoperative pain. This article reviews the safety and efficacy of central and perineural continuous infusions for postoperative pain control in children. The literature confirms the very low rate of complications and adverse effects of regional anesthesia in children. However, clinicians need to be aware of the key points for performing a block and placing a catheter in children: good knowledge of anatomic and physiologic differences between adults and children is necessary; the use of newer local anesthetics, such as ropivacaine and levobupivacaine, increases the therapeutic window; and that it is mandatory to work with dedicated pediatric equipment. Through the use of new techniques such as nerve mapping and/or ultrasound the success of blocks can be improved and the risks reduced.

Intravenous clonidine infusion in infants after cardiovascular surgery

BACKGROUND

The aim of this study was to investigate the hemodynamic profile and heart rhythm in infants who were given intravenous clonidine infusion after prolonged analgesia/sedation following cardiac surgery.

METHODS

This is a single center retrospective review. A total of 542 cardiovascular surgical procedures in infants aged 0-24 months with congenital heart disease were performed between 01/2003 and 12/2005 at the Deutsches Herzzentrum in Berlin. The majority received no long-term analgesia/sedation, but 50 (9%) of these infants received clonidine (dosed at 0.18-3.6 microg.kg(-1).h(-1)) for sedation and to reduce withdrawal symptoms such as CNS hyperactivation, hypertension, tachycardia, and fever. The hospital records of these infants were studied.

RESULTS

Fifty infants (median age 5.0 months, median body weight 5.3 kg, 32 males/18 females) received prolonged analgesia/sedation to ensure hemodynamic stability. Clonidine infusion started on day 5 (median) after surgery. During clonidine treatment we found an age-related normalized profile of hemodynamic parameters with a reduction of heart rate and mean arterial pressure from the upper norm to the mean within 24 h (P < 0.001). In no case did clonidine cause low blood pressure resulting in additional therapy to reach the target blood pressure. There were no adverse effects on cardiac rhythm, especially no onset of atrioventricular block. Midazolam, fentanyl, and other opioids could be ended on day 4 of clonidine treatment.

CONCLUSIONS

Although off-label, it is feasible to use clonidine infusions in infants in the PICU setting after cardiac surgery without hemodynamic problems arising.

Periduralanästhesie

In epidural anaesthesia, the anaesthetist injects one or more drugs into the epidural space bordering on the spinal dura mater to achieve a "central" and/or "neuraxial" block. It is one of the earliest techniques in anaesthesia, originally performed exclusively with local anaesthetic agents. Adding other drugs and combining epidural with general anaesthesia or adapting the technique to the needs of children has extended the list of indications. Continuous epidural analgesia is an important tool in postoperative pain management. More and more often, the increasing proportion of patients who have comorbidities or are permanently taking medication that modulates the clotting system demands that the anaesthesiologist balance the individual risks and benefits before inducing epidural anaesthesia.

Prospective comparison of sevoflurane and desflurane in formerly premature infants undergoing inguinal herniotomy

BACKGROUND

Formerly premature infants having inguinal herniotomy have been at a high risk of postoperative apnoea, newer less soluble anaesthetic agents may reduce this risk.

METHODS

Thirty infants, under 37 weeks gestation and under 47 weeks post-conceptional age, undergoing inguinal herniotomy had an inhalational induction with sevoflurane and were randomly allocated to sevoflurane (group S) or desflurane (group D) for maintenance. All infants received i.v. atracurium 0.5 mg kg(-1), rectal acetaminophen 20 mg kg(-1) and caudal bupivacaine 0.25% 1 ml kg(-1). Infants were monitored for apnoeas (using nasal thermistry and impedance), haemoglobin oxygen desaturations and bradycardias for 12 h before and after operation with an Alice 4 polysomnograph. Emergence timings were recorded.

RESULTS

There was no difference between pre- and postoperative incidence of apnoeas in either group, and no group difference between desflurane and sevoflurane in terms of pre- and postoperative ventilatory events or in the number of apnoeas in the postoperative period (nine patients in group D and five patients in group S had apnoeas). Median times to first movement, tracheal extubation, eye opening and first cry were all faster with group D (group D: 3.0, 10.0, 9.0 and 11.0 min and group S: 7.0, 15.1, 13.5 and 16.1 min, respectively). No infant had problems with airway irritation on emergence and no infant required airway intervention for apnoea.

CONCLUSIONS

Infants wake faster from general anaesthesia when maintained with desflurane as compared with sevoflurane, but no difference in postoperative respiratory events was demonstrated between the groups.