Vol 11 | Issue 1 | January-April 2025 | Page: 11-13| MD Athar, Kandukuri Bala Subramanyam
DOI: https://doi.org/10.13107/jaccr.2025.v11.i01.260
Open Access License: CC BY-NC 4.0
Copyright Statement: Copyright © 2025; The Author(s).
Submitted: 10/09/2024; Reviewed: 09/10/2024; Accepted: 19/12/2024; Published: 10/04/2025
Author: MD Athar [1], Kandukuri Bala Subramanyam [1]
[1] Department of Anaesthesia, KIMS Hospital, Kurnool, Andhra Pradesh, India.
Address of Correspondence
Dr. MD Athar,
Consultant Anaesthesiologist, KIMS Hospital, Kurnool, Andhra Pradesh, India.
E-mail: mohdathar88@gmail.com
Abstract
Background: Methylmalonic Acidemia (MMA) is an inborn error of metabolism caused by a deficiency in methylmalonyl CoA mutase, leading to increased protein catabolism, hyperammonemia and metabolic acidosis. This condition presents challenges to the Anaesthesiologist for perioperative management due to metabolic instability, particularly during surgeries.
Case Presentation: A 1-year-old male child, weighing 8.5 kg and diagnosed with MMA, was posted for bilateral orchidopexy for undescended testes. Anaesthetic management was focused on preventing hypoglycemia, managing surgical stress with good analgesia, and avoiding metabolic acidosis. L-carnitine and methylcobalamin were administered preoperatively. General anaesthesia with inhalational induction was given, and a pre-incision caudal block for analgesia was performed. The child recovered without any complications.
Conclusion: We report a case of successful anaesthetic management of a child with MMA, emphasizing the importance of knowing the pathophysiology of the disease to prevent metabolic complications.
Keywords: Methylmalonic acidemia, Bilateral orchidopexy, Pediatric anaesthesia, Metabolic disorder.
Introduction:
Methylmalonic Acidemia (MMA) is an inborn error of metabolism that affects the body’s ability to break down certain proteins and fats. It is caused by a deficiency of the enzyme methylmalonyl CoA mutase. The resulting accumulation of methylmalonic acid leads to hyperammonemia, severe metabolic acidosis, and neurological deficits. Perioperative management of patients with MMA is challenging due to the potential for metabolic decompensation, hyperammonemia, and hypoglycemia during surgery and in the immediate post-operative period.
Case Presentation:
A 1-year-old male child, weighing 8.5 kg, presented with a known diagnosis of MMA for bilateral orchidopexy for bilateral undescended testes. MMA was diagnosed by tandem mass spectrometry and genetic testing. (Fig. 1) The scans showed that both the testes were in the inguinal region and hence the decision of open repair was taken. (Fig. 2)
In order to minimize the metabolic derangements, the NPO period was strictly limited to 6 hours prior to the surgery (As per ASA guidelines) to avoid hypoglycemia and No clear liquids were given 2 hours before surgery, and 0.9% DNS (dextrose saline) infusion @34ml per hour was continued in the High Dependency Unit (HDU) till the baby was shifted to the Operation theatre. Pre operative Pediatrician consultation was obtained regarding the administration of L carnitine and Methylcobalamin.
In the operating room, after connecting standard ASA monitors ECG, NIBP and Pulse oximeter, Blood sugars were checked and was 65 mg/dL, yet the child didn’t show any signs of hypoglycemia and was active and pink, so intravenous bolus of 10 mL of 5% dextrose was given to avoid further hypoglycemia. The patient was premedicated with Inj glycopyrrolate 40 mcg IV and Inj Fentanyl 20 mcg IV and inhalation induction with sevoflurane which initially was 8% on the dial and later decreased to 2% was performed. Endotracheal intubation was achieved with a 4.0 mm uncuffed ET tube after Inj Atracurium 5mg IV administration and was secured after 5 point auscultation. Anaesthesia was maintained using Oxygen : Air 50% : 50% and Sevoflurane 2%. Analgesia was achieved with a land mark guided caudal block using the modified Armitage formula, which was given prior to the incision. The baby didn’t require any additional doses of Neuro muscular blocking drugs. Blood sugars were checked twice intraop and were above 120 mg/dl. IV fluid 0.9% Dextrose Normal Saline (DNS) was continued as the maintainance fluid intraoperatively @ 34ml per hour. Perioperative hypothermia was prevented by using Forced air warming device throughout the perioperative period. Intraoperative temperature monitoring was not done. Arterial blood gas analysis (ABG) was done and showed pH of 7.30 with Bicarbonate levels of 16.3, Paco2 levels of 34.0 and base deficit of 8.8 with normal lactate levels for which no correction was done. [Figure 3] The total duration of surgery was 45 mins and the child was later extubated without any adverse events. (Fig. 4, 5)
Discussion:
Methyl malonic acidemia is a rare autosomal recessive disorder caused by mutations affecting the enzyme methylmalonil-coA mutase, leading to the accumulation of methylmalonic acid and toxic metabolites. This results in severe metabolic disturbances, including metabolic acidosis, hyperammonemia, hypoglycemia, and hyperkalemia, all of which are of significant concerns during Anaesthesia management. [1]
The perioperative period in MMA patients can trigger metabolic crisis due to stress, fasting, or surgery, resulting in decompensation marked by metabolic acidosis and electrolyte disturbances. Hyperkalemia, in particular, has been associated with life-threatening arrythmias in these patients, as seen in a documented case of severe arrythmias following the induction of anaesthesia due to hyperkalemia. [2]
Certain drugs should be avoided in MMA patients, particularly Propofol, which is controversial due to the risk of Propofol Infusion Syndrome (PRIS), a condition characterized by metabolic acidosis, rhabdomyolysis and cardiac failure. While some suggest that an induction dose is not harmful, majortiy advise caution. [3]
Succinylcholine, a depolarizing muscle relaxant, is also typically avoided in these patients due to its potential to cause hyperkalemia, exacerbating the metabolic disturbance already present in these patients. [4]
Preoperative administration of L-carnitine and Cobalamin is essential in the management of these patients. L-carnitine helps by facilitating the removal of toxic organic acids and improving fatty acid metabolism, while cobalamin serves as a co-factor in reducing methylmalonic accumulation in responsive forms of MMA. Their combined use helps stabilize metabolic function before surgery. [5]
MMA patients require close peri-operative monitoring to prevent metabolic crises. Blood glucose, acid-base status, and potassium levels must be monitored to avoid hypoglycemia, acidosis and hyperkalemia. Hyperkalemia, though rare, can be fatal, as shown in reports of acute arrythmias caused by severe potassium imbalance in these patients. [2] [5]
Conclusion:
We report a case of successful anaesthetic management in a child with Methylmalonic acidemia undergoing bilateral orchidopexy. A multidisciplinary approach, careful perioperative monitoring, an appropriate metabolic management were key to preventing complications an ensuring smooth recovery.
Clinical message:
Methylmalonic acidemia presents significant anaesthetic challenges due to the risk of metabolic decompensation. Key aspects of management include avoiding certain drugs like Propofol and Succinylcholine, vigilant monitoring for acidosis and electrolyte imbalances, and administering L-carnitine and Cobalamin preoperatively. A multidisciplinary approach involving anaesthesiologists and pediatricians, is crucial to prevent life-threatening complications.
References
1. Fenton WA. Gravel RA Rosenblatt DS 2001. Disorders of propionate and methylmalonate metabolism The Metabolic & Molecular Bases of Inherited Disease8 th CR ScriverW. S. SlyD. ValleMcGraw-Hill New York2165-2193. Fenton, WA, Gravel, RA, and Rosenblatt, DS. 2001:2165-93.
2. Chao PW, Chang WK, Lai WI, Liu C, Chan KH, Tsao CM. Acute life-threatening arrhythmias caused by severe hyperkalemia after induction of anesthesia in an infant with methylmalonic acidemia. Journal of the Chinese Medical Association. 2012 May 1;75(5):243-5.
3. Manoli I, Sloan JL, Venditti CP. Isolated methylmalonic acidemia.
4. Kölker S, Valayannopoulos V, Burlina AB, Sykut-Cegielska J, Wijburg FA, Teles EL, Zeman J, Dionisi-Vici C, Barić I, Karall D, Arnoux JB. The phenotypic spectrum of organic acidurias and urea cycle disorders. Part 2: the evolving clinical phenotype. Journal of inherited metabolic disease. 2015 Nov;38:1059-74.
5. Leonard JV, Morris AA. Urea cycle disorders. InSeminars in neonatology 2002 Feb 1 (Vol. 7, No. 1, pp. 27-35). WB Saunders.
| How to Cite this Article: Athar MD, Subramanyam KB | Anaesthetic Management of a Child with Methylmalonic Acidemia Undergoing Bilateral Orchidopexy – A Case Report | Journal of Anaesthesia and Critical Care Case Reports | January-April 2025; 11(1): 11-13. https://doi.org/10.13107/jaccr.2024.v11.i01.260 |
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