High Dose Vitamin C Ameliorates Incidence of Pulmonary Complications Post-Cardiac Surgery

Written by Chrystal Moulton, Science Writer. The incidence of PPC was 36.7% overall and was significantly lower in the intervention group versus the control group (13.3% versus 60.0%, P<0.001).

Cardiac operations with extracorporeal circulation generates systemic inflammatory responses that can range from mild to severe with or without multi organ dysfunction¹. Generally, the overall stress induced by anesthesia, perfusion, and the surgery initiates the severe oxidative stress and systemic inflammatory response^2,3. Among the organs affected by the inflammatory response is the lungs. Patients who undergo cardiac surgeries with extracorporeal circulation experience postoperative pulmonary complications. These complications, however, lead to death, disability, significant morbidity, and increased healthcare costs^4,5. Vitamin C is an antioxidant that has already been explored for various disease states and use in conventional medicine⁶. Vitamin C has also been investigated to reduce the system inflammatory response and severe oxidative stress that follows cardiac surgery with extracorporeal circulation^3,6,7. However, the timing, dose, and route of administration has not been established. In this clinical study, researchers investigated the effect of a high dose of vitamin C provided after beginning cardiac surgery with extracorporeal circulation on the incidence of postoperative pulmonary complications⁸.

The study was designed as a randomized, single-blind, interventional trial. Patients 18 years of age or older electing for cardiac surgery with extracorporeal circulation irrespective of the type of operation planned were included in this trial. Patient data was not included in the analysis if the patient died due to non-pulmonary reasons; surgery was more than 6hours long; or if patient voluntarily withdrew consent. Patients were excluded if they had previous cardiac surgery, anemia, pulmonary disorders, allergy to vitamin C, gout, significant oxaluria, glucose-6-phosphate dehydrogenase enzyme deficiency, thalassemia, and hemochromatosis. Patients were divided into 2 groups:

• Control group: receiving normal saline intraoperatively at the beginning of cardiac surgery and every 6h at 30min IV infusion post-operation for 48hours.
• Intervention group: receiving 50mg/kg every 6h of Vitamin C. The first does was given at the beginning of cardiac surgery and every 6h at 30min IV infusion post-operation for 48hours. After 48hours, patients were given 2g of vitamin C daily until discharge through the gut. They were instructed to continue 2g of vitamin supplementation for 1-week post-discharge.

Demographic, anthropometric, clinical, and laboratory data was collected for each patient before the surgery and entered into both medical records and a separate database. Researchers assessed the physical status of each patient before the surgery using the American Society of Anesthesiologists score (ASA score) and the degree of organ dysfunction after the surgery using the Sequential Organ Failure Assessment (SOFA) after the surgery. The incidence and severity of postoperative pulmonary complications was scored by two independent and blinded assistants daily. The degree and severity of post-operative pulmonary complication (PPC) was graded on a scale of 0 to 5 (with zero indicating no complications and 5 indicating death before discharge). 48 hours after surgery when systemic inflammatory response is expected, certain inflammatory markers, postoperative oxygenation and ventilation, and parameters of renal function were analyzed. The primary endpoint of the study was the incidence and severity of postoperative pulmonary complications in the intervention group versus the control.

One hundred and sixty patients who met study criteria was included in this study. Eighty patients were randomly allocated to each group (control or intervention). In the end, 75 patients in each group were included in the analysis. The average age of participants in both groups was roughly 66 years old. At baseline, diastolic pressure, BMI, duration of surgery and chronic renal failure was significantly higher in the control group versus the intervention group. Additionally, based on ASA scores, both groups had advanced systemic disease and severe comorbidities. However, preoperative pulmonary status was good in both groups (PPC scores of 0 or 1). The incidence of PPC was 36.7% overall and was significantly lower in the intervention group versus the control group (13.3% versus 60.0%, P<0.001). Also, the severity of postoperative pulmonary complications (PPCs) was significantly lower in the intervention group compared to the control (P<0.001). Researchers found that patients in the intervention group had significantly lower chances of PPC scores ≥3 (OR = 0.468, P<0.001). Even after adjusting for confounders, the incidence of PPCs remained significantly different between the two groups (OR = 0.521, P<0.001). Researchers also observed significant improvement in other secondary outcome measures. [See Table 1]

Table 1. Additional outcomes of parenteral vitamin C in patients following cardiac surgery

Overall, the trial demonstrated that high dose vitamin C provided significant support in reducing the incidence and severity of postoperative pulmonary complications in patients undergoing cardiac surgery with extracorporeal circulation. This trial also demonstrated additional benefits in the vitamin C group including better postoperative renal function, less damage to the lungs, as well as lower hospital mortality, ICU stay, and ICU readmissions. Additional studies will be needed to verify these results.

Source: Karadžić Kočica, Milica, Arsen Ristić, Ivan Soldatović, Dejan Lazović, Jelena Čumić, Miloš Grujić, Radmila Karan et al. “The Influence of High-Dose Parenteral Vitamin C on the Incidence and Severity of Postoperative Pulmonary Complications in Cardiac Surgery with Extracorporeal Circulation: A Randomized Controlled Trial.” Nutrients 16, no. 6 (2024): 761.

© 2024 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/
4.0/).

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Posted May 14, 2024.

Chrystal Moulton BA, PMP, is a 2008 graduate of the University of Illinois at Chicago. She graduated with a bachelor’s in psychology with a focus on premedical studies and is a licensed project manager. She currently resides in Indianapolis, IN.

References:

1. Squiccimarro E, Labriola C, Malvindi PG, et al. Prevalence and Clinical Impact of Systemic Inflammatory Reaction After Cardiac Surgery. J Cardiothorac Vasc Anesth. Jun 2019;33(6):1682-1690. doi:10.1053/j.jvca.2019.01.043
2. Churpek MM, Zadravecz FJ, Winslow C, Howell MD, Edelson DP. Incidence and Prognostic Value of the Systemic Inflammatory Response Syndrome and Organ Dysfunctions in Ward Patients. Am J Respir Crit Care Med. Oct 15 2015;192(8):958-64. doi:10.1164/rccm.201502-0275OC
3. Semler MW, Wheeler AP. Systemic inflammatory response syndrome after cardiac surgery: time for a change. Chest. Jun 2014;145(6):1181-1182. doi:10.1378/chest.14-0438
4. Miskovic A, Lumb AB. Postoperative pulmonary complications. Br J Anaesth. Mar 1 2017;118(3):317-334. doi:10.1093/bja/aex002
5. Fischer MO, Brotons F, Briant AR, et al. Postoperative Pulmonary Complications After Cardiac Surgery: The VENICE International Cohort Study. J Cardiothorac Vasc Anesth. Aug 2022;36(8 Pt A):2344-2351. doi:10.1053/j.jvca.2021.12.024
6. Oudemans-van Straaten HM, Spoelstra-de Man AM, de Waard MC. Vitamin C revisited. Critical care (London, England). Aug 6 2014;18(4):460. doi:10.1186/s13054-014-0460-x
7. Long MT, Hess AS, McCarthy DP, DeCamp MM. Power for the Sickest: Vitamin C for Vasoplegia after Cardiac Surgery. J Cardiothorac Vasc Anesth. Apr 2020;34(4):1123. doi:10.1053/j.jvca.2019.09.018
8. Karadžić Kočica M, Ristić A, Soldatović I, et al. The Influence of High-Dose Parenteral Vitamin C on the Incidence and Severity of Postoperative Pulmonary Complications in Cardiac Surgery with Extracorporeal Circulation: A Randomized Controlled Trial. Nutrients. Mar 7 2024;16(6)doi:10.3390/nu16060761