A study on the effect of Haruan fish extract (Channa striatus) on wound healing and quality of life of coronary artery bypass grafting (CABG) patients: A prospective, double-blind, randomized, controlled trial

Introduction

Wound healing involves complex interaction between cells and mediators, which starts once the wound is inflicted, and continues for weeks. Healing is still a major problem in any kinds of surgery, particularly in cardiothoracic surgery. This is a surgery that involves a long incision over the sternum where delayed sternal wound healing is not an uncommon sight. Sternal wound infections are a known cause of morbidity and might require intervention from plastic surgeons. In severe cases, it could even lead to mortality.

Sternal wound infection is fairly uncommon as compared to leg wounds, with a frequency between 0.7%¹ and 3.3%², but reports based on extended surveillance on post-discharge cases showed incidences up to 9.7%³. As expected, the end-result of sternal wound infection include wound dehiscence, mediastinitis, pericarditis, osteomyelitis and endocarditis⁴ with associated mortality between 14% and 47%^5–9.

Leg wound infection, though not life-threatening as chest-wound, increases the overall morbidity of the patients. It is noted that there is a threefold increase in cost of managing patients with leg wound as compared to those with an uncomplicated postoperative course⁷. Complications such as wound breakdown, cellulitis, lymphangitis, fat necrosis, and delayed healing are known sequelae of leg wound infection. It is not surprising that the incidence has been reported to be as high as 24%^10–13.

We have noticed that despite the different types of dressings being used, the rate of infection did not vary that much^14–17. The reason for this seemingly indifferent incidence of wound infection is due to the fact that the healing was by primary intention¹⁷. The cause for such an infection is primarily deep-seated problem of the pre-operative and intra-operative rather than merely the superficial issue of wound dressing¹⁸.

With that understanding, perhaps a better way in promoting wound healing would be a systemic approach rather than topical; with all other factors remaining constant. Extracts of Channa striatus, locally known as Haruan (snakehead), a fresh water, air-breathing, carnivorous fish, has been proven to influence the different phases of the wound healing process^19,20. Laboratory studies conducted on Sprague Dawley rats have shown that Channa striatus has antinociceptive effects that could reduce postoperative pain^21–23. Channa striatus has been shown to contain all essential amino acids for wound healing, particularly glycine. Glycine is a major component of human skin collagen that acts synergistically with other essential amino acids that facilitate in tissue healing process. It also has a high content of arachidonic acid and polyunsaturated fatty acids that can promote prostaglandin synthesis, which is a very important compound that creates and removes inflammation, which is part of the healing process¹⁹. It has also been shown that Channa striatus promotes remodelling of collagen by the synthesis of inter, and intra molecular protein cross-linking, producing a marked increase in the tensile strength that accentuates wound healing²⁴. Furthermore, the fish also has certain fatty acids that have been reported to possess anti-inflammatory activity such as stearic acid and oleic acid²⁵.

Up to this point, all the above studies that looked into the healing and nociceptive properties of Channa striatus have been on animal models. This is the first study that is conducted on human subjects. We therefore conducted a prospective randomized control trial (RCT) and assess not only wound healing and wound infection after CABG, but also the health related QOL of such patients, considering the anti-htinflammatory and anti-nociceptive effect of Channa striatus. The potential value of patenting such natural product and it’s usage on other types of surgical wounds, including laparotomy and Caesarean section; compounded with the commercial value associated, makes it even more attractive.

Methodology

Sampling

Inclusion criteria:

• 1. Male or female

• 2. More than 18 years of age

• 3. Elective, urgent, or emergency coronary artery revascularization

Exclusion criteria:

• 1. Less than 18 years old

• 2. Refusal to have surgery

• 3. Inability to give informed consent

• 4. Documented allergy to fish or fish product

Pre-operative

The two randomized groups based in the National Heart Institute (IJN) were matched according to sex, age, New York Heart Association (NYHA) criteria (indicates patients’ hearts condition and the severity of their symptoms. Class I to Class IV), ejection fraction, and diabetic status. Randomization was done via simple computer-generated randomization with odd or even RN numbers in each group. Operative and peri-operative conditions were also similar for both groups. All subjects received an identical prophylactic antibiotic regime consisting of Cefazolin 2gm at induction and 1 gm 12 hourly for 48 hours. Gentamicin 2mg/kg was also given at induction.

Intra-operative

A uniform method of wound closure and disinfection protocol was followed. Skin was disinfected with Betadine followed by povidone iodine 10%. The method for wound closure was similar for both groups, namely double layer sutures up to the intra-cutaneous skin. Going from deep up to the surface, the pre-sternal fascia was closed with 1-0 Vicryl suture in a continuous type followed by closure of the subcutaneous tissue. Skin was closed with Monocryl 3/0 in subcuticular manner. For the leg wound, the subcutaneous tissue was closed with Vicryl 0, followed by continuous skin suture with Maxon 3/0.

Titanium clips were used to secure branches of the internal mammary artery on the chest wall and branches of the saphenous vein in the leg. Some saphenous veins branches were ligated with Silk 3/0 instead. When closing the sternum, steel wire sutures were used.

Post-operative

Both groups took either, 2 capsules (500mg) of Channa striatus, or 2 capsules of placebo (maltodextrine) daily for a minimum of six weeks, starting from day one post-operatively. If the patient was still ventilated, the capsules were broken, and the content administered via a Ryle’s tube. Investigators and healthcare workers, as well as participants, were blinded to the capsules received. Only the manufacturers who supplied the drug were aware of the meaning of the label on the capsule, letter E or O.

Consent and ethics

Prior to randomization of participants, the study was explained, including risk and benefits to suitable candidates, and written consent was obtained. Consenting participants were then randomized into the trial. The study was conducted with ethical approval from the National Heart Institute Malaysia (IJNEC/04/2011) and National Medical Research Register (NMRR-17-360-34772).

Measurement

Wound Infection. Both sternal and leg wounds were inspected and assessed daily until subjects were discharged. Information at 6 weeks and 3 months postoperatively was collected from patients in the clinic or over the telephone. Each wound was scored using the ASEPSIS system (Refer to Supplementary Material 1). We realized that this is a more objective method in assessing wound infection rather than being subjective and open to biases. The end result from this scoring system will determine whether the wound is considered significant or not by obtaining a score of 21–30. If the wound is more serious with a deep seated wound infection, it will have a score of 21–30, and should there be evidence of bone infection, then the score would be >41.

Wound pain. A Visual Analogue Scale (VAS) of 0 to 10 cm was used to assess the degree of wound pain. A score of 0 cm represents “no pain” and a score of 10 represents “severe pain”. Pain assessment will be recorded from day 1 and will continue daily until the subject is discharged. It will be further assessed during the clinic visit at 6 weeks and 3 months postoperatively.

Mobilization. Similarly, a VAS of 0 to 10 cm was used to assess the degree of mobilization. A score of 0 cm represents “inability to walk” and 10 cm represents “excellent mobilization.” Assessment of mobilization was made on post-operative days 3 and 4 since there was restrictions in mobility on days 1 and 2 after surgery. Similarly, it was assessed again during the clinic visit at 6 weeks and 3 months postoperatively.

Health related quality of life. In this study, we decided to assess the health-related quality of life (HRQOL) using the Nottingham Health Profile (NHP) – Part 1. The NHP is known to be very efficient in clinical studies. It looks into parameters such as discomfort and pain apart from the general well-being of a patient. And it is found to be more objective in assessing the health status of the patients. There were 38 subjective statements which were divided into six sections on NHP Part 1 namely physical mobility, social isolation, emotional reaction, energy, pain, and sleep. Each section will have a score range from between 0–100 by adding the item weight to each answer that is deemed positive.

The questionnaire was distributed to both groups of patients before CABG and at six weeks and three months during clinic visit postoperatively. The questionnaires were administered using the questionnaire-interview approach.

Statistical analysis

Data was analysed with IBM SPSS Statistics version 24.0 and examined for normality using the Kolmogorov-Smirnoff test and stem-and-leaf plot. When normal, we proceeded with parametric tests; however, if not normal, we proceeded with the non-parametric tests.

The results were presented as means ± standard deviations for scaled measurements; with numbers and percentages for categorical measurements. The unpaired t-test was used to examine mean differences for wound infection, wound healing, pain, and mobilization across the two groups. Differences in proportions was examined using the Chi-square test.

In examining the mean QOL score, differences between the two groups (pre-operative, six weeks, and three months), the mixed mode two-way repeated measure ANOVA with post-hoc multiple comparison test (between and within subjects) of the two groups was performed.

To determine the factors influencing the change of QOL after CABG, with the dependent variable being binary (improved or worsened), we performed an initial simple logistic regression (SLogReg), and examined the statistical significance of each independent variable such as the amount of revascularization and duration of surgery on the outcome. We then performed a multiple logistic regression (MLogReg) including variables with a level of significance ≤ 0.20 in the multivariate logistic regression and controlling for the effects of possible confounding variables (sex, age, NYHA Criteria, ejection fraction, and diabetic status). A p value of 0.05 was taken as the level of significance.

Refer to Figure 1 for the study flow chart.

Figure 1. Study flow chart.

Results

253 patients were recruited from January 2012 till August 2014. Only 183 patients (72.3%) completed the study up to three months follow-up. A total of 40 patients (15.8%) were lost during follow-up and 5.5% discontinued their enrolment in the study. The main reason why these patients were lost during follow-up was for a simple reason that they did not turn-up for the scheduled follow-up. This is due to the fact that IJN is the largest heart centre in the Malaysia and the patients were from all over the country. And since many were former government servants and stay in the rural areas all over the country, travelling to the city centre was not only time-consuming but expensive. Seven patients (2.8%) had their operations cancelled.

The patients were predominantly male (86.2%), the majority being Malay (86.7%), followed by Indians (15.4%) and Chinese (7.9%).

The mean weight was 71.92±13.10 kg ranging from 45–132kg and the mean BMI was 27±4.3 kgm².

125 (49.4%) of them received Capsule O (placebo) and 128 (50.6%) received Capsule E that contains Haruan extract.

Out of the 246 patients who underwent CABG, 224 patients (91.06%) had an elective operation, while only 8.94% were emergency cases.

Off-pump CABG was performed on only 16.7% of patients as compared to the conventional on-pump (83.3%). Mean operation time was 186.94±48.9 minutes ranging from 75 to 350 minutes. The mean bypass time was 82.08±27.55 minutes.

65 patients (26.42%) developed atrial fibrillation (AF) post-operatively while 10 patients (4.07%) developed supraventricular tachycardia (SVT).

Only 10 patients (4.07%) had their chest re-opened. Known complications such as renal failure occurred in only 2 patients (0.81%) and stroke in another 2 patients (0.81%) as well. Overall, the mortality rate was 3.6% with nine patients dead.

Mean hospital stay was 10±11.86 days and mean ICU stay was 2.97±7.67 days. Both the duration of ICU stay (2.31±2.65), and hospital stay (9.24±8.58) was shorter for patients on Capsule E in comparison to Capsule O (3.69±10.7 and 11.1±14.6, respectively), although this was not statistically significant (p=0.170, 0.230, respectively).

The ASEPSIS score showed no statistically significant difference between Capsule E and O on Day 3, 6, 6 weeks and 3 months (p=0.243, 0.805, 0.117, 0.980, respectively).

There was no statistically significant difference in the mean pain score using the visual analogue scale (VAS) between the two groups post-operatively (Capsule E: 0.39±0.25, Capsule O: 0.43±0.24, p=0.290) and no difference on mobilization (p=0.668).

Assessment of HRQOL comparing both groups showed no significant difference at discharge (p-values: emotion=0.48, physical=0.54, energy=0.16, social=0.071, sleep=0.87, and pain=0.29) and assessment at 6 weeks and 3 months follow-up showed no statistically significant difference for all six components of HRQOL except for social level at 3 months (p=0.04).

Refer to Figure 2 for study results flow chart.

Figure 2. Study results flow chart.

Limitations

There were a few limitations to this study. The first is in getting the patients’ consent in enrolling into the study. A few patients had this misconception that Haruan would cause hypertrophic wound or sometimes even keloid. This was the misperception that they had and no amount of talking or persuasion would convince them. And of course, considering that their enrolment is voluntary, their withdrawal from the study is unavoidable. Hence there were almost 30% of patients who did not manage to complete the study. The second limitation is regarding the compliance of the patients to take the capsules provided to them. While they were on the ward, this issue of compliance did not arise, since the Haruan capsules or the placebo were served by the attending staff nurses. However, compliance was not ensured when the patients were discharged from the wards. The third is regarding how the Nottingham Health Profile was administered. We decided for the questionnaire to be conducted by the researcher and not independently answered by the patients without the presence of the researcher. This could have resulted in some bias when answering the question on NHP by the patients. While we understand that this interview mode is not free from bias, it is still the least burdensome method, which only requires the respondent to speak the same language as the interviewer, and to have a basic verbal and listening skills. Considering that almost all Malaysians speak Malay and a majority of them speak English as well, this is probably a more effective way. We believe that the interview method would allow us to clarify ambigu ous questions, and maintain the motivation.

Discussion

Wound healing has always been an obsession among surgeons. And despite the advance in surgical dressings over the years, surgeons have always been trying to find novel ways in promoting wound healing. Haruan or Channa striatus has been known amongst the locals since ancient times to promote healing, and has been used as a form of nutritional supplement. Normally the fish is consumed after it is fried, grilled or boiled; as a traditional remedy for wound healing especially after delivery of caesarean section. There, however, are no clinically randomized trials so far that have been conducted to prove or disprove this belief.

Our study – the first as far as the authors are concerned - has shown the clinical benefit of Channa striatus in promoting wound healing among CABG patients. The study was conducted in a double-blind manner, and only after the results were analyzed, were the researchers informed of the content of Capsule E and Capsule O. There was no way for the researchers to know before hand of the content of the capsules.

The results scientifically confirm the long-held belief of the benefit of Haruan fish. The properties of Haruan to promote wound healing have been postulated. Perhaps it was the way in which Haruan had positive influence on the immune system in regulating the prostaglandin synthesis via the possession of ω-3 polyunsaturated fatty acids has made it effective in stimulating the healing process²⁰.

The healing process requires both amino acids and fatty acids. And these have been found in abundance in Haruan fish. Compounds such as glycine, alanine, proline, arginine, serine, leucine, isoleucine, and phenylalanine are known to combine with aspartic and glutamic acid to form polypeptides. These form the basic foundation for healing to take place. Studies have demonstrated that these amino acids and fatty acids are present in Haruan²⁰.

Similarly, Haruan also contains a high content of arachidonic acid, 20:4ω6. This arachidonic acid is thought to be related to the wound healing property of Haruan²⁰. The platelet aggregation and adhesion to the endothelial tissue that initiates blood clotting is thought to be induced by arachidonic acid.

Researchers at the Analytical Biochemistry Research Centre at the Universiti Sains Malaysia have done proteomic profiling on Haruan extract and found out that 25% and 26% of the total protein detected in freeze- and spray-dried C. striatus extract respectively are actin, myosin, and tropomyosin²⁷. A recent study has also shown that actins are essential for a range of cellular functions including; the maintenance of cell shape, polarity, cell division, cytokinesis, vesicle and organelle movement, cell signaling, establishing and maintaining cell junctions, and the regulation of transcription²⁸. And this process is postulated to take effect during the process of re-epithelialisation, which is part of proliferative phase during a healing process²⁸.

It is also known that actin acts in synchrony with myosin in promoting wound healing. This biomechanical process in driving cell motility has previously been shown²⁹.

Tropomyosin, which controls the isoform-specific regulation of diverse actin filaments, is also suggested to play a role during wound healing³⁰. This finding is also confirmed by Lees et al³¹. in their report on the role of tropomyosin as a regulator of actin functioning during the process of wound healing.

So it is possible that actin, myosin and tropomyosin, which can be found in Haruan, contributed to the expedition of the wound healing process.

Two types of collagen, namely type I and type II, have also been detected in Haruan through proteomic profiling^27,32. Collagen is a well-known substance that gives tensile strength during wound healing. In fact, it has been shown that collagen and other components of the extra-cellular matrix mainly formed the granulation tissue³³. It is said that the granulation tissue then contracted, slowly closing the wound, and at the same time aligning the collagen fibres in the extracellular matrix³³. This leads us to believe that the collagen found in Haruan promotes the maturation of granulation tissue, and hence, expedite wound healing.

Apart from the healing properties, Haruan has also been proven to promote the quality of life of patients’ post-CABG. The HRQOL study shows that there was significant change in the energy, pain, emotion and physical level.

These findings demonstrate the much-acclaimed “rejuvenating effect” of Haruan. It is not an exaggeration to propose that the high content of fatty acids and certain amino acids coupled with the anti-nociceptive effects^34,35 might have indicated that they somehow contributed to the natural well-being of patients’ post-CABG.

Conclusion

Our clinical study, though laborious, has demonstrated the effects of using Channa striatus, a local fish known as Haruan, which is easily processed into capsules in promoting wound healing, reducing pain via its anti-nociceptive effect and improving quality of life of patients after coronary artery bypass grafting surgery. This is the first randomized, double blind clinical trial being conducted on this matter although there have been anecdotal evidence on the efficacy of Haruan. It is inferred that a faster recovery from surgery confers an advantage in terms of resources to an overall economic benefit. Reduction in the percentage of wound infection also resulted in reduced hospitalization cost. We believe this will lead to the successful commercialization of Haruan, which could be reared commercially as a nutraceutical product.

Data availability

Dataset 1 - Health Related Quality of Life for all participants 10.5256/f1000research.13372.d196593³⁶

Dataset 2 – Surgical wound healing data for all participants 10.5256/f1000research.13372.d196594³⁷