Shoulder Pain Following Laparoscopic Cholecystectomy: Factors Affecting the Incidence and Severity

Abstract

Background:

Laparoscopic cholecystectomy (LC) has become the standard treatment for gall bladder disease. However, despite its low degree of invasiveness, many patients complain of postoperative pain and postoperative nausea/vomiting. This study was planned to evaluate different factors affecting the incidence and severity of postoperative shoulder-tip pain after LC.

Patients and Methods:

One hundred consecutive patients who were treated for gall bladder stone by LC at the Gastroenterology Surgical Center, Mansoura University, Mansoura, Egypt, during the period from October 2008 to January 2010, were randomized according to different pnemoperitonum pressures (8, 10, 12, and 14 mm Hg). Each group comprises 25 patients.

Results:

There were 62 patients reported to have postoperative shoulder-tip pain during the first 12 hours after operation, which decreased to 9 patients on the 10th postoperative day. A significant difference was observed in the prevalence of pain at different pressures, 11% with low pressure and increased to 20% with high pressure. The incidence of shoulder-tip pain was significantly more in patients with a longer duration of the operation of >45 minutes at 12 hours (23 [76.7%] versus 39 [55.7%]; P = 0.04), at 24 hours (23 [76.7%] versus 29 [41.4%]; P = 0.009), and at 3 days postoperatively (19 [63.3%] versus 20 [28.6%]; P = 0.01). The volume of used gases during the operation had no effect on the incidence or severity of shoulder-tip pain after LC. Also, the use of intraoperative analgesics had no effect on the incidence or severity of shoulder-tip pain after LC.

Conclusions:

The origin of pain after LC is multifactorial. We recommend the use of the lower pressure technique during LC, and as patients with and without drains have similar incidence of postoperative shoulder pain, drains should not be used with the intention of preventing shoulder pain.

Introduction

Laparoscopic cholecystectomy (LC) has become the standard treatment for gall bladder disease.^1,2 However, despite its low degree of invasiveness, many patients complain of postoperative pain (PP) and postoperative nausea/vomiting, which may be due to residual pnemoperitonum.^3,4

Pain after LC may occur in the upper abdomen, lower abdomen, back, or shoulders. It may be transient or persistent for about 3 days.⁵ CO₂ gas remains in the subdiaphragmatic space after laparoscopy for >24 hours.⁶ It has been suggested by some that this gas is converted to carbonic acid on the moist peritoneal surfaces, irritating the diaphragm and leading to referred shoulder and neck pain.⁷

Others believe that rapid distension of the peritoneum may be associated with overstretching of the diaphragmatic muscle fibers,⁸ tearing of blood vessels, traumatic traction of nerves, and release of inflammatory mediators.⁹ The prolonged presence of shoulder-tip pain suggests excitation of the phrenic nerve.¹⁰

Joris et al.¹¹ reported that after LC, visceral pain predominates on the first day but subsides from a peak soon postoperative, but shoulder pain, minor on the first day, increases and becomes significant on the following day.

Many trials have been employed to reduce shoulder-tip pain after LC, including perioperative analgesics,¹² subcutaneous and intramuscular analgesia,¹³ intraperitoneal saline and bupivacaine,^14,15 a gas drain,¹⁶ and nitrous oxide pneumoperitoneum.¹⁷

This study was planned to evaluate different factors affecting the incidence and severity of postoperative shoulder-tip pain after LC.

Patients and Methods

One hundred consecutive patients who were treated for gall bladder stone (“either elective or having acute cholecystitis in 11 patients”) by LC at the Gastroenterology Surgical Center, Mansoura University, Mansoura, Egypt, during the period from October 2008 to January 2010 were eligible for this prospective study. The exclusion criteria included age >80 years, history of upper laparotomy, hemorrhagic tendency due to cirrhosis, American Society of Anesthesiology grade of 3 or more, patients refused to give informed consent and patients in whom the laparoscopic procedure was converted to open cholecystectomy or converted from low to high were excluded from the study.

Informed consent was taken for all patients to do the operation and to include in this study. This study was approved by local ethical committee.

With the same type of anesthesia and same antibiotics (third-generation cephalosporin), surgery was performed using the conventional four ports: umbilical port, port below xiphoid, and two ports below right costal margin.

Four groups of patients (25 patients each) were randomly selected for different pressures of pnemoperitonum (8, 10, 12, and 14 mm Hg).

The patients started oral feeding at 8 hours postoperatively; postoperative ultrasound was performed on the day of discharge, as it is a routine practice in our center before discharge to show any collection or free fluid in the abdomen. Actually, most of our colleagues use the drain as routine, but we did not. We used it nearly in half of the patients to evaluate its role, but we found no difference. The patients were usually discharged within the first 24 hours and after removal of drain.

PP was evaluated at 12 hours, 24 hours, 3 days, 1 week, and 10 days after operation using a visual analog scale (VAS) with which each patient noted the severity of pain at each evaluated time using a linear between zero (no pain) and 10 (severe pain).

The VAS consists of a line, usually 100 mm long, whose ends are labeled as the extremes (“no pain” and “pain as bad as it could be”); the rest of the line is blank. The patient was asked to put a mark on the line indicating their pain intensity (at the present time, over the past week, over the past 2 weeks, etc.). The distance between that mark and the origin was measured to obtain the patient's score. Sometimes, descriptive terms, such as “mild,” “moderate,” and “severe,” or numbers are provided along the scale for guidance, and the scale is then referred to as a graphic rating scale.¹⁸

The patients were evaluated at 12 and 24 hours postoperatively and on the 10th postoperative day. The other two evaluations at days 3 and 7 were through questionnaires given to the patients to fill.

Postoperative analgesia in the form of Ketorolac (0.5 mg/kg) was administered intramuscularly when required. If the patients still complained of pain and required strong analgesic, 1 mg/kg pethidine was administered intramuscularly. The total dose of these medications was recorded.

Variables that may affect the incidence and severity of shoulder pain after LC, including sex, duration of the operation, amount of CO₂ used in the operation, different pressures, presence of abdominal drain, and use of intraoperative analgesic, were recorded.

Statistical analysis of data in this study was performed using SPSS version 10. For continuous variables, descriptive statistics were calculated and reported as mean ± standard deviation. Categorical variables were described using frequency distributions. The Student's t-test for paired samples was used to detect differences in the means of continuous variables, and chi-square test was used in cases with low expected frequencies. The analysis of variance (ANOVA) one-way test was done for more than two groups (a P-value of <0.05 was considered significant).

Results

This study was carried out from October 2008 to January 2010. Of 116 consecutive patients with gall bladder stone who were treated by LC at the Gastroenterology Surgical Center, Mansoura University, during the recruiting period, 100 patients (38 men and 62 women) were eligible and entered the study. The patients' mean age was 42.38 ± 10.67 (range, 18–61) years. Sixteen patients were excluded: in 2 patients the laparoscopic procedure was converted to open cholecystectomy, 1 patient refused to give informed consent, 3 patients had history of upper laparotomy, 2 patients had grade 3 by American Society of Anesthesiology, in 4 patients the laparoscopic procedure was converted from low to higher pneumoperinum pressure, and 4 patients had cirrhotic liver.

There were 62 patients reported to have postoperative shoulder-tip pain during the first 12 hours after operation, which decreased to 9 patients on the 10th postoperative day. Shoulder-tip pain, when it occurred, started at 2–6 hours postoperatively, increased at 12 hours, and then diminished after that time. The pain scores of patients with postoperative shoulder-tip pain were recorded using a VAS (3.83 + 3.06, 2.43 + 1.93, 1.63 + 1.69, 0.86 + 1.14, and 0.45 + 0.8211 at 12 hours, 24 hours, 3rd day, 7th day, and 10th day, respectively) (Table 1).

Table 1.

Demographic Data

Variables
Age	42.38 ± 10.67 (18–61)
Sex
Male	38 (38%)
Female	62 (62%)
Mean duration of operation	36 ± 9.9 (20–50)
Pain
At 12 hours	62
At 24 hours	52
At 3 days	39
At 7 days	28
At 10 days	9
Severity of pain
At 12 hours	3.83 + 3.06
At 24 hours	2.43 + 1.93
At 3 days	1.63 + 1.69
At 7 days	0.86 + 1.14
At 10 days	0.45 + 0.8211

A significant difference was observed in the prevalence of postoperative shoulder-tip pain at different pressures (8, 10, 12, and 14 mm Hg), which was reported throughout the entire postoperative period. The shoulder pain was significantly less when the pressure decreased, as shown in Table 2. The mean intensity of PP assessed by the VAS was significantly lower throughout the entire postoperative period in the lower pressure pneumoperitoneum group as long as day 10 postoperatively. The details are presented in Table 2. The most pronounced differences were seen at 12 hours and on 1st, 3rd, and 7th days after the operation. In addition, the daily requirement for analgesics was significantly lower in the lower pressure pneumoperitoneum group (single to twice doses of nonsteroidal anti-inflammatory drugs (NSAIDs) in the first 48 hours) than in the higher pressure pneumoperitoneum patients (up to 3–4 doses of NSAIDs in the first 2–3 postoperative days).

Table 2.

Effect of Intrabdominal Pressure on Shoulder Pain

Variables	Group A (25 patients) (8 mm Hg)	Group B (25 patients) (10 mm Hg)	Group C (25 patients) (12 mm Hg)	Group D (25 patients) (14 mm Hg)	P-value
Presence of shoulder-tip pain
12 hours	11 (44%)	12 (48%)	19 (76%))	20 (80%)	0.01
24 hours	9 (36%)	8 (32%)	17 (68%)	18 (72%)	0.04
3 days	3 (12%)	7 (28%)	13 (52%)	14 (56%)	0.03
7 days	3 (12%)	4 (16%)	10 (40%)	11 (44%)	0.05
10 days	1 (4%)	2 (8%)	3 (12%)	3 (12%)	0.2
VAS of pain
12 hours	1.62 + 1.88	2.01 + 2.02	5.46 + 2.67	6.25 + 2.55	0.001
24 hours	1.27 + 1.67	1.92 + 2.23	3.08 + 1.38	3.48 + 1.55	0.02
3 days	0.44 + 1.08	1.36 + 1.49	2.28 + 1.27	2.44 + 2.04	0.03
7 days	0.20 + 0.50	0.76 + 1.09	1.36 + 1.07	1.12 + 1.42	0.05
10 days	0.1 + 0.27	0.28 + 0.67	0.68 + 0.90	0.76 + 1.05	0.23

VAS, visual analog scale.

The incidence of postoperative shoulder-tip pain was insignificantly higher in patients with abdominal drain at different postoperative times. However, the mean intensity of PP assessed by the VAS was significantly higher at the 12th hour postoperatively in the patients with abdominal drain (4.96 + 3.05 versus 3.16 + 2.92; P = 0.01) (Table 3).

Table 3.

Effect of Drain on Shoulder Pain

Variables	With drain (56 patients)	Without drain (44 patients)	P-value
Presence of shoulder-tip pain
12 hours	35 (62.5%)	27 (61.4%)	0.9
24 hours	27 (48.2%)	25 (56.8%)	0.39
3 days	18 (32.1%)	21 (47.7%)	0.11
7 days	12 (21.4%)	16 (36.4%)	0.10
10 days	5 (8.9%)	4 (9.1%)	0.97
VAS of pain
12 hours	4.96 + 3.05	3.16 + 2.92	0.01
24 hours	2.41 + 1.89	2.45 + 1.97	0.9
3 days	1.47 + 1.54	1.75 + 1.81	0.42
7 days	0.81 + 1.28	0.89 + 1.03	0.74
10 days	0.43 + 0.82	0.46 + .80	0.84

The incidence of postoperative shoulder-tip pain was significantly more in patients with a longer duration of the operation of >45 minutes at 12 hours (23 [76.7%] versus 39 [55.7%]; P = 0.04), at 24 hours (23 [76.7%] versus 29 [41.4%]; P = 0.009), and at 3 days postoperatively (19 [63.3%] versus 20 [28.6%]; P = 0.01). The mean intensity of PP assessed by the VAS was significantly higher at the 12th hour postoperatively in the patients with a longer duration of the operation of >45 minutes (5.93 + 2.66 versus 2.98 + 2.81; P = 0.001). No intergroup differences in VAS scores were observed at 24 hours, 3 days, 7 days, and 10 days after the operation with respect to the duration of the operation (Table 4).

Table 4.

Effect of Duration of the Operation on Shoulder Pain

Variables	<45 minutes (70 patients)	>45 minutes (30 patients)	P-value
Presence of tip shoulder pain
12 hours	39 (55.7%)	23 (76.7%)	0.04
24 h	29 (41.4%)	23 (76.7%)	0.009
3 days	20 (28.6%)	19 (63.3%)	0.01
7 days	15 (21.4%)	13 (43.3%)	0.16
10 days	7 (10%)	2 (6.7%)	0.64
VAS of pain
12 hours	2.98 + 2.81	5.93 + 2.66	0.001
24 hours	2.22 + 2.06	2.96 + 1.45	0.08
3 days	1.46 + 1.68	2.03 + 1.70	0.12
7 days	0.71 + 1.12	1.20 + 1.14	0.053
10 days	0.33 + 0.71	0.72 + 0.99	0.03

A significant difference was observed in the prevalence of postoperative shoulder-tip pain with respect to the gender at different postoperative times. The VAS scores were significantly and consistently higher for female patients than male patients: 4.06 for females versus 3.46 + 2.82 for males (P = 0.03) at 12 hours after the operation, 3.15 + 1.84 versus 2.12 + 2.02 (P = 0.04) at 48 hours after the operation, and 2.41 + 1.72 versus 1.97 + 1.61 (P = 0.05) at 3 days after the operation. No intergroup differences in VAS scores were observed at 7 and 10 days after the operation (Table 5).

Table 5.

Effect of Gender on Shoulder Pain

Variables	Male (38 patients)	Female (62 patients)	P-value
Presence of shoulder-tip pain
12 hours	18 (47.4%)	44 (70.9%)	0.02
24 hours	14 (36.8%)	38 (61.3%)	0.04
3 days	10 (26.3%)	29 (46.8%)	0.05
7 days	9 (23.7%)	19 (30.6%)	0.77
10 days	2 (5.3%)	7 (11.0%)	0.30
VAS of pain
12 hours	3.46 + 2.82	4.06 + 1.98	0.03
24 hours	2.12 + 2.02	3.15 + 1.84	0.04
3 days	1.97 + 1.61	2.41 + 1.72	0.05
7 days	1.21 + 1.16	0.64 + 1.08	0.09
10 days	0.60 + 0.91	0.35 + 0.74	0.14

The volume of gases used during the operation had no effect on the incidence or severity of shoulder-tip pain after LC (Table 6). Also, the use of intraoperative analgesics had no effect on the incidence or severity of shoulder-tip pain after LC (Table 7).

Table 6.

Effect of Volume on Shoulder Pain

Variables	<15 L (42 patients)	>15 L (58 patients)	P-value
Presence of shoulder-tip pain
12 hours	25 (59.5%)	37 (63.7%)	0.41
24 hours	20 (47.6%)	32 (55.2%)	0.73
3 days	17 (40.4%)	22 (37.9%)	0.87
7 days	12 (28.6%)	16 (27.6%)	0.73
10 days	3 (7.1%)	6 (10.3%)	0.87
VAS of pain
12 hours	3.6 + 3.24	3.96 + 2.95	0.64
24 hours	1.88 + 2.05	2.84 + 1.74	0.1
3 days	1.23 + 1.47	1.91 + 1.79	0.04
7 days	0.71 + 1.19	0.96 + 1.10	0.28
10 days	0.28 + 0.67	0.56 + 0.90	0.08

Table 7.

Effect of Intraoperative Analgesic on Shoulder Pain

Variables	Intraoperative analgesic (50 patients)	No intraoperative analgesic (50 patients)	P-value
Presence of shoulder-tip pain
12 hours	27 (54%)	35 (70%)	0.10
24 hours	22 (44%)	30 (60%)	0.11
3 days	16 (32%)	23 (46%)	0.15
7 days	9 (18%)	19 (38%)	0.02
10 days	6 (12%)	3 (6%)	0.29
VAS of pain
12 hours	3.34 + 2.90	4.33 + 3.17	0.10
24 hours	2.23 + 1.85	2.64 + 1.99	0.29
3 days	1.42 + 1.57	1.84 + 1.79	0.21
7 days	0.72 + 1.10	1.00 + 1.17	0.22
10 days	0.36 + 0.72	0.54 + 0.90	0.27

Discussion

LC has largely replaced conventional open cholecystectomy. The main reason for this change is the more tolerable postoperative period, shorter hospitalization, and early return to work.^19–21 However, shoulder pain, backache, nausea, and vomiting due to residual pneumoperitoneum are absent in conventional laparotomy. Diaphragmatic stretch during laparoscopy is one of the proposed pathways for PP, especially shoulder pain.^1,22,23

LC is most often performed by creating pneumoperitoneum by pumping CO₂ to the abdominal cavity using pressure-regulating automatic insufflators. The maintenance of elevated intrabdominal pressure for the duration of the procedure is associated with numerous adverse effects involving the circulatory and respiratory systems, as well as the kidneys; some of these side effects result from a positive intraperitoneal pressure itself, whereas others are associated with carbon dioxide absorption from the peritoneal cavity to blood.^24–26

The origin of pain after LC is multifactorial, with pain arising from the incision sites, the pneumoperitoneum, and the cholecystectomy.²¹ The exact mechanism of pain related to pneumoperitoneum after laparoscopy has yet to be clarified. Proposed mechanisms include diaphragmatic stretching, chemical irritation of peritoneum by carbonic acid formed from carbon dioxide, and sympathetic nervous system activation derived from hypercarbia and leading to amplification of local tissue inflammatory response as well as splanchnic mucosal ischemia. Rapid distension of the peritoneum may be associated with overstretching of the diaphragmatic muscle fibers, tearing of blood vessels, traumatic traction of nerves, and release of inflammatory mediators. The prolonged presence of shoulder-tip pain suggests excitation of the phrenic nerve.^8–10,27

Several studies reported that the use of the lower pressure technique during LC results mostly in a remarkable reduction of pain arising from pneumoperitoneum, as seen in our study.^28–30 Barczynski et al.²⁹ found that lower pressure pneumoperitoneum has been proven to be sufficient for performing LCs in patients when compared with as many individuals subjected to the same procedure employing standard-pressure pneumoperitoneum.

Some reports have suggested that women may have a lower pain threshold and less tolerance of painful stimuli than men.^31,32 The lower pain threshold of women may be supported by the finding that more women than men reported severe baseline pain in our study. Sex differences in pain perception have been attributed to a different socialization process for men and women, which influence bodily experience and the willingness to communicate distress.³³ Hormone variations also could help to explain sex differences in pain experience and response to analgesics.^34,35 Uchiyama et al.³⁵ concluded that women exhibit higher pain intensity after LC and have larger adjusted analgesic requirements than men, and that patients with high VAS scores tend to require larger doses of analgesics.

In our study, postoperative shoulder pain was intensified by drain insertion after LC, as reported by Kazuhisa et al.³⁶ Abdominal drain is not effective in alleviating PP after LC, but drainage tube is considered to intensify postoperative shoulder-tip pain. Thus, we recommend that no drain should be inserted after LC unless there are serious intraoperative complications. Barczynski et al.²⁹ reported that shoulder-tip pain subsided in some patients immediately following the removal of a peritoneal drain, which favors the supposition that the pain was caused by the mechanical irritation inflicted by the drain and not only by the stretching of the diaphragm and diaphragmatic nerve endings by pneumoperitoneum. However, Shen et al.³⁷ concluded that PP was milder in the drainage group after laparoscopic surgery, but the difference was small. Also, Jorgensen et al.³⁸ showed that evacuation of postoperative pneumoperitoneum by drains reduced postoperative shoulder pain.

Conclusions

The origin of pain after LC is multifactorial. The use of the lower pressure technique during LC results mostly in a remarkable reduction of pain arising from pneumoperitoneum. Women may have a lower pain threshold and less tolerance of painful stimuli than men. Abdominal drain is not effective in alleviating PP after LC. Thus, we recommend the use of the lower pressure technique during LC, and as patients with and without drains have similar incidence of postoperative shoulder pain, drains should not be used with the intention of preventing shoulder pain.

Footnotes

Disclosure Statement

No competing financial interests exist.

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