The current study was performed to compare the effects of IP and IV dexamethasone on the prevention of PONV and POP in patients who underwent laparoscopic cholecystectomy. The results obtained in this study were also used to investigate the effect of IP dexamethasone on the hemodynamic status of patients. In a meta-analysis study, the authors demonstrated that granisetron, a commonly used antiemetic drug, could prevent PONV more effectively combined with dexamethasone (
20).
Moreover, numerous randomized controlled trials (RCTs) investigated the combination of dexamethasone and other antiemetics in different doses to evaluate the prophylactic effects on PONV in laparoscopic cholecystectomy. However, the population in such trials was usually limited, which meant that the results were probably uncertain. A recent meta-analysis suggested that 8 mg of IV dexamethasone acts as the optimal effective dose for the prevention of PONV, especially when combined with ondansetron. The studies that used the aforementioned dose reported a lower incidence of PONV and a lower rate of antiemetic drugs consumption (
15).
Some studies, including a study performed by Elhakim et al., suggested that the routine preoperative administration of IV dexamethasone, alone or in combination with other oral antiemetic medications, such as ondansetron or metoclopramide, reduced the risk of PONV (
21). Feo et al. suggested that the preoperative administration of dexamethasone, alone and without other antiemetic medications, could prevent PONV after laparoscopic cholecystectomy (
22). All the aforementioned studies demonstrated that dexamethasone could act as a potent antiemetic to prevent PONV when used intraoperatively. The current study demonstrated that the IP administration of dexamethasone could significantly reduce the severity of nausea after the operation; however, this effect was not shown to act on the severity of vomiting and the incidence of PONV. There are discrepancies between the results, which could be due to different doses, routes of administration, or surgical techniques. In addition, the risk factors of nausea and vomiting were not considered in all studies and could be responsible for the differences in the results.
The POP is another common side effect of laparoscopic operations and usually occurs due to incision wounds, visceral pain, and diaphragm irritation which causes pneumoperitoneum and shoulder pain (
22). Consequently, uncontrolled pain can make patients dissatisfied with the quality of surgery and improve the risk of morbidity and mortality (
16). In recent years, investigations on analgesics have made remarkable advantages in postlaparoscopic pain management (
8). For example, one of such recent randomized controlled studies by Gayam et al. suggested that combining IV dexamethasone with other analgesics, such as IP bupivacaine, could be significantly effective in the reduction of PONV and POP (
8).
Previous studies postulated that IP dexamethasone could act as a potent agent to relieve shoulder pain in females who underwent laparoscopic gynecological operations. In one such method, Asgari et al. demonstrated shoulder pain to be a significant side effect after gynecological laparoscopy, which occurred due to carbon dioxide pneumoperitoneum (usually occurring due to diaphragm injury during laparoscopy) (
7). The results showed that the pain was significantly lower in severity in patients who received a single dose of 16 mg of IP dexamethasone, compared to that of the placebo group of patients. The aforementioned study also reported that the postoperative administration of analgesic drugs, such as opioids and narcotics, was lower in patients with IP dexamethasone than in the placebo group (
7).
Moreover, Hosseini Valami et al. compared the effects of bupivacaine, dexamethasone, and morphine to the placebo (saline) in the IP route of administration on pain after a caesarian section in 144 pregnant women (
16). The aforementioned study reported that patients who received 16 mg (diluted to 30 cc) of IP dexamethasone and 30 cc of bupivacaine (25%) experienced lower pain and had a lower VAS score, compared to patients who received 5 mg (diluted to 30 cc) of IP morphine (
16).
Some studies compared the effects of different doses of intraoperative dexamethasone with or without other drugs on POP. Sultan et al. reported that the preoperative administration of 0.1 mg/kg single-dose IV dexamethasone could enhance the quality of patient recovery and improve pain control after laparoscopic cholecystectomy, compared to lignocaine (
23). Additionally, Elsakka et al. studied the effect of different corticosteroids on POP and proved that the administration of IP dexamethasone and hydrocortisone could reduce abdominal pain and shoulder pain in patients and consequently reduce the need for the administration of analgesics after laparoscopic cholecystectomy, without causing any significant side effect to patients (
23,
24).
A systematic review in collaboration with the international Procedure Specific Postoperative Pain Management (PROSPECT) that aimed to establish proper protocols for the effective management of postoperative laparoscopic cholecystectomy pain reviewed clinical trials within 2006 (after the previous version) to 2017. The results of the aforementioned study recommended preoperative dexamethasone as an effective medication to reduce POP (up to 48 hours after the operation) and PONV. The aforementioned study recommended a combination of preoperative dexamethasone with metoclopramide, ondansetron, and rofecoxib to reduce the levels of the most severe pain that was experienced by patients (
25). However, some clinical trials reported contrasting results. For instance, Mohtadi et al., in a randomized, double-blind study on 122 patients, reported that no significant difference was witnessed in POP between dexamethasone group patients (who received up to 8 mg of IV dexamethasone) and control group patients (who received 2 mL of normal saline as the placebo) (
26). Ali et al., in a study on 75 patients, reported that pain scores were significantly lower in patients receiving ondansetron-bupivacaine than patients receiving dexamethasone-bupivacaine and the control group (receiving saline-bupivacaine) (
27).
In addition, Zahra et al. reported that the IP administration of bupivacaine-magnesium sulfate was a more effective combination in the reduction of POP and analgesic consumption, compared to bupivacaine-dexamethasone, in a population of about 60 patients undergoing laparoscopic cholecystectomy (
28). The researchers also suggested that this could be due to the prolonged anesthesia duration due to the use of the bupivacaine-magnesium sulfate combination and nalbuphine consumption after operation (
28). As previously mentioned, studies demonstrated the dexamethasone effect as a potent drug to reduce POP when used intraoperatively. However, there are discrepancies between the results, which could be due to different doses of used dexamethasone, surgeon skills, or even different combinations of dexamethasone and other drugs. The current study showed that the administration of 8 mg IP dexamethasone intraoperatively was associated with a significant POP reduction in comparison to 8 mg IV dexamethasone and the placebo. No drug combination was used in the current study, and dexamethasone was used only with the placebo.
Furthermore, the patients’ hemodynamic status was another outcome that was evaluated in the current study. Other researchers also studied this issue. For example, a study performed by Rajnikant et al. reported no significant differences in mean arterial pressure, heart rate, and blood oxygen saturation during surgery between the two intervention groups (i.e., dexamethasone-palonosetron and dexamethasone-ondansetron), compared to the control (saline) group (
29). Similarly, in the current study, there was no significant difference in the hemodynamic status of patients during the surgery between the IV, IP, and control groups.
Alkaissi et al. compared the antiemetic effect of dexamethasone with and without metoclopramide on the incidence and severity of nausea and pain in about 120 patients (
30). The authors reported that a combination of dexamethasone-metoclopramide, compared to metoclopramide or dexamethasone alone, significantly reduced the severity of nausea; however, it did not affect the incidence of nausea. Alkaissi et al. also demonstrated the effect of this combination on the incidence and severity of pain after laparoscopic operations (
30).
Another double-blind RCT study performed by Ismail et al. on 80 participant females undergoing gynecological laparoscopies compared the effect of IP and IV dexamethasone (and not a placebo) on PONV and POP (
10). They reported that IP dexamethasone could reduce POP and the need for meperidine 24 hours after gynecologic cholecystectomy more effectively, compared to IV dexamethasone. Ismail et al. also demonstrated IP dexamethasone to reduce the incidence of PONV in the first 24 hours after gynecologic laparoscopies (experience of nausea and vomiting in 16 and 5 patients in the IV and IP groups, respectively). However, this effect was not reported similarly regarding the severity of nausea in patients (
10).
Furthermore, in a recent study, Nouri et al. evaluated the effects of IP dexamethasone (and not IV) on PONV and shoulder pain in 130 patients undergoing gynecologic laparoscopy (
31). The results showed that about 40% of the IP dexamethasone group experienced PONV, compared to that of the control (placebo) group. Nouri et al. also reported that the mean VAS score in the IP dexamethasone group was lower than the placebo group during the first 24 hours after the operation (
31). The researchers suggested considering IP dexamethasone for routine administration in gynecologic laparoscopic operations (
31). Nonetheless, the current study demonstrated that IP dexamethasone could significantly reduce the severity of nausea (and not the incidence of PONV and severity of vomiting) after the operation. On the other hand, the patients who received IP dexamethasone during laparoscopic cholecystectomy experienced lower pain than the IV and control groups.
The current study concluded that the administration of 8 mg IP dexamethasone intraoperatively in laparoscopic cholecystectomy was associated with reduced PONV during the first 24 hours after the operation. However, this antiemetic feature of IP dexamethasone was not reported as a significant effect. Nevertheless, 8 mg dexamethasone administered intraoperatively significantly reduced POP and the subsequent use of analgesics during the 24 hours after laparoscopic cholecystectomy, compared to the results of the IV and control groups.
Different from previous studies that have been performed over the past years, the current study not only investigated the effect of the IP dexamethasone administration on PONV, compared to the control group, but also compared it to that of IV dexamethasone administration. In addition, the present study considered the effect of dexamethasone on both PONV and POP and not just one complication. However, the current study had some limitations, including the limited study population and no evaluation of the side effects of dexamethasone in each group. It is suggested to carry out further studies on larger populations, different doses, and different timing intervals to compare the effects of IP and IV dexamethasone administration during surgery to achieve enough evidence to recommend the routine administration of IP dexamethasone for preventing the complications of laparoscopic cholecystectomy (e.g., PONV and POP) and consequently increasing patient satisfaction. Furthermore, there is a need for a systematic review and meta-analysis to collect all the results of different studies.