Incidence and significance of pneumoperitoneum in continuous ambulatory peritoneal dialysis

Complications of Peritoneal Dialysis Part I: Mechanical Complications

Peritoneal dialysis (PD) is a form of KRT that offers flexibility and autonomy to patients with ESKD. It is associated with lower costs compared with hemodialysis in many countries. However, it can be associated with unexpected interruptions to or discontinuation of therapy. Timely diagnosis and resolution are required to minimize preventable modality change to hemodialysis. This review covers mechanical complications, including leaks, PD hydrothorax, hernias, dialysate flow problems, PD-related pain, and changes in respiratory mechanics. Most mechanical complications occur early, either as a result of PD catheter insertion or the introduction of dialysate and consequent increased intra-abdominal pressure. Late mechanical complications can also occur and may require different treatment.

Managing Hospitalized Peritoneal Dialysis Patients: Ten Practical Points for Non-Nephrologists

Although nephrologists are responsible for the long-term care of dialysis patients, physicians from all disciplines will potentially be involved in the management of patients with kidney failure, including patients on peritoneal dialysis, the major home-based form of kidney-replacement therapy. This review aims to fill knowledge gaps of non-experts in peritoneal dialysis and to highlight key management aspects of in-hospital care of patients on peritoneal dialysis, with a focus on acute scenarios to facilitate prompt decision-making. The clinical pearls provided should enable non-nephrologists to avoid common pitfalls in the initial assessment of peritoneal dialysis-related complications and guide their decision regarding when to refer their patients to a specialist, resulting in improved multidisciplinary patient care.

Peritoneal Dialysis with Marked Pneumoperitoneum

Pneumoperitoneum, the presence of free air within the peritoneal cavity, is often caused by the perforation of gas-containing viscus and commonly requires surgical treatment. However, in patients with peritoneal dialysis, free air is commonly seen on X-ray. We present the case of a patient with peritoneal dialysis with marked pneumoperitoneum. A 75-year-old Japanese male with end-stage renal disease due to antineutrophil cytoplasmic antigen-associated vasculitis had been receiving continuous ambulatory peritoneal dialysis for 9 years. He had a poor appetite and general malaise without abdominal pain or fever. These symptoms gradually worsened, and he was hospitalized. At the time of admission, chest X-ray revealed bilateral free air in the abdomen. Subsequent computed tomography of the abdomen revealed marked pneumoperitoneum. Peritonitis due to perforation of the digestive tract was considered; however, the absence of abdominal pain, fever, and turbidity of dialysis drainage indicated that peritonitis was unlikely. Insufficient air venting during continuous ambulatory peritoneal dialysis bag replacement was suspected. The bag was carefully changed, resulting in a gradual decrease in the free air. We encountered a patient with continuous ambulatory peritoneal dialysis who had significant free air in the abdominal cavity in the absence of peritonitis. The source of the air was determined to be the dialysis bag due to insufficient venting during replacement. This case underscores the importance of instructing patients with continuous ambulatory peritoneal dialysis on the thorough removal of air from the bag during replacement.

Peritoneal Dialysis-Associated Peritonitis: Suggestions for Management and Mistakes to Avoid

Peritonitis is a common complication of peritoneal dialysis that is associated with substantial morbidity and mortality. Peritonitis increases treatment costs and hospitalization events and is the most common reason for transfer to hemodialysis. Although there is much focus on preventing peritoneal dialysis–associated peritonitis, equally as important is appropriate management to minimize the morbidity of a peritonitis episode when it has occurred. Despite the presence of international guidelines on peritonitis treatment, the evidence base to support optimal peritonitis treatment practices is lacking, leaving the practitioner to rely on clinical experience and extrapolate from across other infection treatment practices. This article reviews common mistakes and misconceptions that we have observed in the management of peritonitis that may compromise treatment success. It also provides suggestions on common controversial aspects of peritonitis management based on the best available literature. Although the use of the word mistakes is somewhat controversial and subjective, we acknowledge that evidence is lacking and have based many of our suggestions on clinical judgment, experience, and available data.

Viscus Perforation in Peritoneal Dialysis Patients: Diagnosis and Outcome

Objective

To determine the incidence and outcome of spontaneous viscus perforation in peritoneal dialysis (PD) patients and which factors could facilitate early diagnosis.

Design

A retrospective chart review was done on all patients with viscus perforation and on a control group with peritonitis secondary to gram-negative organisms.

Setting

A tertiary care University Hospital Peritoneal Dialysis program.

Patients

All patients with surgically proven spontaneous viscus perforation from 1978 to June 1992 (n = 15). A group of control patients (n = 15) with gram-negative bacterial peritonitis was also reviewed for comparison.

Interventions

None.

Main Outcome Measures

Hospital days, patient survival after perforation, and return to peritoneal dialysis were the main outcomes measured. Peripheral white blood cell (WBC) count, PD fluid WBC count with differential, PD fluid cultures, radiologic information, and surgical intervention were also evaluated. Data were analyzed using the Mann-Whitney test to determine significant differences between the two groups.

Results

Viscus perforation occurred in 15 of the 431 patients on PD from 1978 to June 1992 (3.5%). In comparison to the control group, patients with viscus perforation had a significantly higher peripheral WBC count (p = .016), a higher mean PD fluid WBC count (p = .006), and a higher mean percentage of polymorphonuclear cells in the PD effluent (p = .038). Multiple organisms on PD fluid cultures were noted in 12 of 15 patients with perforation and in only 3 control patients. Pneumoperitoneum was seen on abdominal or chest radiograph or computerized tomographic (CT) scan in 10 of 15 patients with perforation and in only 1 of 15 patients in the control group. All patients with viscus perforation required surgery and 6 expired. Only 1 death occurred in the control group. Only 1 of the 9 patients surviving perforation was able to resume PD, in contrast to 13 of 14 surviving control patients.

Conclusion

We conclude that viscus perforation is associated with high morbidity, mortality, and technique failure. Diagnosis may be made by repeatedly searching for intraperitoneal free air on radiograph or CT scan in patients with persistently elevated peripheral and PD fluid WBC count, and for multiple organisms on PD fluid culture.

Predictors of negative intraoperative findings at emergent laparotomy in patients with cirrhosis

BACKGROUND

Emergent surgery in the setting of decompensated cirrhosis is highly morbid. We sought to determine the clinical factors associated with negative intraoperative findings at emergent laparotomy.

METHODS

We performed a retrospective cohort study of consecutive inpatients with a diagnosis of cirrhosis (ICD-9 571) admitted to the Beth Israel Deaconess Medical Center (Boston, MA) who underwent emergent, nonhepatic, abdominal surgery between May 6, 2005 and September 3, 2012.

RESULTS

Eighty-six patients with cirrhosis were included with a mean model for end-stage liver disease score of 21.3 ± 7.95 and a 90-day mortality rate of 39.5%. Twelve (16.2%) patients had negative laparotomies. Negative intraoperative findings were independently associated with (1) paracentesis prior to a preoperative diagnosis of perforated viscus (P = 0.006), (2) development of an indication for emergent surgery after 24 h into hospital admission for another reason (P = 0.020), and (3) a preoperative diagnosis of bowel ischemia (P = 0.005), with odds ratios of 10.1 (CI 1.92-66.83), 5.80 (CI 1.32-33.39), and 11.1 (CI 2.08-77.4), respectively. Free air on computed tomography (CT) imaging was found in 64.3% (9/14) of patients who had a paracentesis within the preceding 48 h compared to 10.1% (7/72) among patients who did not undergo a paracentesis (P < 0.001). Only 45% of patients with free air following a paracentesis had positive findings at laparotomy compared to 100% in those without a preceding paracentesis (P = 0.038). Negative laparotomy was independently predictive of in-hospital mortality (OR 4.7; P = 0.034).

CONCLUSION

The possibility of a negative laparotomy is suggested by preoperative clinical factors. In particular, free air following a paracentesis does not necessarily indicate that operative intervention is required. Consideration of close observation before laparotomy in these patients is reasonable.

Free air on CT and the risk of peritonitis in peritoneal dialysis patients: a retrospective study

BACKGROUND

Intra-abdominal free air is found frequently in patients undergoing peritoneal dialysis (PD). Some studies have investigated an association between intra-abdominal free air and peritonitis in PD patients. However, most used chest X-rays, which are of limited sensitivity, and the association was not made clear. We conducted a retrospective study of the association between peritonitis and intra-abdominal free air using computed tomography.

METHODS

The presence and volume of free air, and its relationship with other variables, were assessed on review of routine examinations in 108 patients. Correlations between the presence of free air and age, duration of PD, continuous ambulatory versus automated PD, presence or absence of a person who assisted in bag changes, exit-site infection, tunnel infection and peritonitis were assessed.

RESULTS

Free air was detected in 29 patients (27.1%). The prevalence of peritonitis was higher in the free air (+) group than in the free air (-) group: 1/40.2 patient-months for free air (+) versus 1/96.9 patient-months for free air (-). The risk ratio of free air for peritonitis was 2.41 (95% confidence interval: 2.28-2.55) and was similar when corrected for age, gender, albumin, diabetes mellitus and body mass index.

CONCLUSION

Free air is an independent risk factor for peritonitis in PD patients. This suggests that bag change procedures should be re-evaluated, and patients re-educated, when necessary.

Long-term pneumoperitoneum in continuous ambulatory peritoneal dialysis (CAPD) caused by handling fault of Stay.Safe(R) system associated to bicaVera solution

We found chronic pneumoperitoneum in two continuous ambulatory peritoneal dialysis patients from two different hospitals. Both patients used the Stay.Safe® system and bicaVera solution, whose extension tubing is not primed with fluid but air-filled, unlike that of the conventional solution bags. This fact, together with a handling fault common to both patients, resulted in the inflow of the air in the tubing of bicaVera bags into the peritoneal cavity during every exchange. We warn of this complication, which must be specifically pointed out during training, and we recommend providing the system with a mechanic device to prevent this handling fault.

Pneumoperitoneum in peritoneal dialysis patients; one centre's experience

The pneumoperitoneum (PP) on upright chest X-ray (CXR) usually indicates a perforated viscus. As peritoneal dialysis (PD) catheter provides an additional port of air entry into the peritoneal cavity, the incidence and clinical significance of PP in PD patients has been debated in the literature (a variable incidence from 4 to 34% has been reported in previous studies). With improvement in patient training and connecting devices of PD catheters, technique-related PP is quite rare. Following a recent patient with PP, we reviewed our 3-year data to evaluate the incidence and significance of this radiological sign in PD patients.

We reviewed all upright CXRs in our PD patients from 2006 to 2008, using an electronic radiology database. Over 3 years, we had a total of 156 patients on PD. We have reviewed a total 312 upright CXRs (mean 2 X-rays per patient), which were performed for various clinical reasons during this period.

Seven PD patients had 11 CXRs showing free air under the diaphragm (total incidence of PP 4% of PD population and 3% of CXR performed in PD patients). One patient had two episodes of PP with a total of four X-rays demonstrating free air. Two patients had surgical complications of PD catheter insertion and PP was diagnosed just after the insertion of PD catheter, both of them needed laparotomy. Five patients had incidental PP, which was possibly technique related. In four of these patients with incidental PP, no definite intervention was needed. However, one of these five patients was symptomatic. We established that the cause of PP was faulty technique. Aspiration of PP with a patient in the Trendelenburg position gave her immediate symptomatic relief. We also retrained her to prevent further episodes of PP.

This review demonstrates the quite low and falling incidence of PP (<4% in a prevalent PD population) most likely due to improvement in training and technique. The air should not enter the peritoneal cavity in normal properly performed exchanges. Air under the diaphragm in a PD patient requires appropriate evaluation to exclude visceral perforation. After that, patient technique of PD exchanges should be reviewed. However, if PP persists, aspiration of air can give symptomatic relief.

Gas-forming bacterial peritonitis mimics hollow organ perforation

Acute abdomen is an emergent condition in the emergency department, and it is mandatory to evaluate it immediately and treat it without delay. Pneumoperitoneum is usually attributed to perforation of the gastrointestinal tract. However, intra-abdominal, gynecologic, urologic, and miscellaneous pathogenesis not related to a perforated gastrointestinal tract had never been described in the past. Approximately 10% of pneumoperitoneum is not associated with hollow organ perforation. There are many imitators of pneumoperitoneum including subphrenic abscess, colon volvulus, Chilaiditi syndrome, and so on. In our case, the gas-forming bacterial peritonitis accounted for the pneumoperitoneum. We presented an 85-year-old man who received laparotomy due to peritonitis, and radiographic subphrenic free air was seen. However, a large amount of ascites was found rather than perforated bowels during the surgical exploration, and the culture of ascites was positive for Pseudomonas aeruginosa.

Noninfectious complications of peritoneal dialysis

Peritoneal dialysis is an established form of renal replacement therapy. With its increasing popularity, we are now encountering a variety of complications. Noninfectious complications are usually less common as compared with infectious complications. In this review, we discuss some of the common noninfectious complications of peritoneal dialysis such as hernias, hydrothorax, hemoperitoneum, pancreatitis, ischemic colitis and necrotizing enterocolitis, pneumoperitoneum, GERD, subcapsular steatosis and hypokalemia. The awareness of these complications will help in early diagnosis and treatment.

Diagnosis and management of enteric disease and abdominal catastrophe in peritoneal dialysis patients with peritonitis

Peritoneal dialysis (PD)-associated peritonitis rates have decreased significantly in recent years, especially Staphylococcus epidermidis and Staphylococcus aureus infections. Rates of gram-negative, polymicrobial, and fungal peritonitis have remained steady. The reported mortality of gram-negative and polymicrobial peritonitis varies widely (4%-50%). Most likely, the reason for this variability is that prognosis depends on the underlying etiology more than the specific microorganisms isolated. Gram-negative, polymicrobial, and fungal infection have variable association with documented visceral disease, and the highest mortality occurs in reports with the highest prevalence of intra-abdominal pathology. The odds ratio of death in PD patients with documented abdominal catastrophe and peritonitis is reported to be 20:1 compared with all other causes. Further reductions in PD-associated peritonitis mortality are likely to depend on earlier diagnosis and better management of intra-abdominal pathology. Presentation with hypotension, sepsis, lactic acidosis, and/or elevation of peritoneal fluid amylase should raise immediate concern for "surgical" peritonitis. Suspicion for visceral disease should also be high in patients with gram-negative, polymicrobial, and fungal infection or those who fail to improve rapidly as judged by clinical signs and symptoms, cell counts, and repeat cultures. Nonlocalizing physical examination and negative or nonspecific results of abdominal computed tomography do not rule out serious intra-abdominal disease. Immediate initiation of broad antibiotic coverage including for anaerobic infection is indicated when bowel pathology is suspected. Urgent surgical consultation, with active discussion and participation by the nephrologist, is advisable when visceral pathology is suspected and the patient is unstable or fails to improve rapidly.

Neumoperitoneo idiopático

We report the case of a 48-year-old man who was admitted to the intensive care unit for acute respiratory distress. After discharge, the patient showed massive pneumoperitoneum. None of the complementary investigations provided information on the cause. The patient underwent surgery but no intraoperative diagnosis was reached. We believe that this case is of interest since pneumoperitoneum is a frequent entity that often leads to emergency laparotomy. The cause is usually perforation, although in a substantial proportion of cases the pneumoperitoneum is non-surgical, or idiopathic.

Pneumoperitoneum: a review of nonsurgical causes

OBJECTIVE

To review causes of nonsurgical pneumoperitoneum (NSP), identify nonsurgical etiologies, and guide conservative management where appropriate.

DATA SOURCE

We conducted a computerized MEDLINE database search from 1970 to 1999 by using key words pneumoperitoneum and benign, nonsurgical, spontaneous, iatrogenic, barotrauma, pneumatosis, diaphragmatic defects, free air, mechanical ventilation, gynecologic, and pelvic. We identified 482 articles by using these keywords and reviewed all articles. Additional articles were identified and selectively reviewed by using key words laparotomy, laparoscopy, and complications.

STUDY SELECTION

We reviewed all case reports and reviews of NSP, defined as pneumoperitoneum that was successfully managed by observation and supportive care alone or that required a nondiagnostic laparotomy.

DATA SYNTHESIS

Each unique cause of nonsurgical pneumoperitoneum was recorded. When available, data on nondiagnostic exploratory laparotomies were noted. Case reports were organized by route of introduction of air into the abdominal cavity: abdominal, thoracic, gynecologic, and idiopathic.

CONCLUSIONS

Most cases of NSP occurred as a procedural complication or as a complication of medical intervention. The most common abdominal etiology of NSP was retained postoperative air (prevalence 25% to 60%). NSP occurred frequently after peritoneal dialysis catheter placement (prevalence 10% to 34%) and after gastrointestinal endoscopic procedures (prevalence 0.3% to 25%, varying by procedure). The most common thoracic causes included mechanical ventilation, cardiopulmonary resuscitation, and pneumothorax. One hundred ninety-six case reports of NSP were recorded, of which 45 involved surgical exploration without evidence of perforated viscus. The clinician should maintain a high index of suspicion for nonsurgical causes of pneumoperitoneum and should recognize that conservative management may be indicated in many cases.

Pneumoperitoneum caused by a perforated peptic ulcer in a peritoneal dialysis patient: difficulty in diagnosis

Peritonitis due to viscus perforation in peritoneal dialysis (PD) patients can be catastrophic. We describe the first reported case of perforated peptic ulcer (PPU) in a PD patient. This 78-year-old man presented with a 1-day history of mild abdominal pain. He had been receiving nocturnal intermittent PD for 2 years and had ischemic heart disease and cirrhosis of the liver. Pneumoperitoneum and peritonitis were documented, but the symptoms were mild. The "board-like abdomen" sign was not noted. Air inflation and contrast radiography indicated a perforation in the upper gastrointestinal tract, and laparotomy disclosed a perforation in the prepyloric great curvature. Unfortunately, the patient died during surgery. This case illustrates that the "board-like abdomen" sign may be absent in PD patients with PPU because of dilution of gastric acid by the dialysate. Free air in the abdomen, although suggestive of PPU, is also not uncommon in PD patients without viscus perforation. Because PD has to be discontinued after laparotomy and exploratory laparotomy may be fatal in high-risk patients, other diagnostic methods should be used to confirm viscus perforation before surgery. PPU, which can be proved by air inflation and contrast radiography, should be suspected in PD patients with pneumoperitoneum and peritonitis.

Inhibitory effect of the intravenous anesthetic, ketamine, on rat mesangial cell proliferation

We studied the effects of ketamine and propofol on rat cultured mesangial cell (MC) proliferation. The 72-h exposure to ketamine (1-100 microM) inhibited [3H]thymidine incorporation into the MC in a concentration-dependent manner. Propofol, however, was not effective at inhibition of MC proliferation at doses from 1 to 100 microM. Ketamine also decreased the cell number at clinically relevant concentrations and increased adenosine 3',5'-cyclic monophosphate (cAMP) levels in MC. We also studied the effects of ketamine on cytokine-induced [3H]thymidine incorporation into the cells. Ketamine decreased the tumor necrosis factor-alpha (TNF-alpha)-, interleukin 1 (IL-1)-, and interleukin 6 (IL-6)-induced [3H]thymidine incorporation into the cells. It also decreased angiotensin II (Ag II)-induced [3H]thymidine incorporation. These results suggest that ketamine has inhibitory effects on MC proliferation, but that propofol does not. Because ketamine inhibits TNF-alpha-, IL-1-, and IL-6-induced MC proliferation, it may be useful in suppressing the cell growth clinically.

Pneumoperitoneum in peritoneal dialysis patients

There has been recent controversy regarding the clinical significance of pneumoperitoneum in patients undergoing peritoneal dialysis. The incidence of pneumoperitoneum has been estimated to be 21.2% to 33.7% in prior studies of peritoneal dialysis patients. Of the peritoneal dialysis patients with pneumoperitoneum, only a small percentage (5.9% to 14.3%) had documented visceral perforations. The controversy arises in that anywhere from 20% to 100% of peritoneal dialysis patients with pneumoperitoneum and peritonitis had visceral perforation, and 32.4% to 57.1% of chronic ambulatory peritoneal dialysis patients had asymptomatic pneumoperitoneum of unknown etiology. These disparate incidences made clinical interpretation of pneumoperitoneum difficult. In addition, prior study result disagreed as to the usefulness of the extent of pneumoperitoneum in predicting visceral perforation. We retrospectively reviewed 694 chest x-ray film and acute abdominal series reports from 1982 to 1993 in 75 peritoneal dialysis patients, with 9.3 +/- 1.3 (mean +/- SEM) x-ray films per patient. The reports were confirmed by reviewing 363 x-ray films (52%). Eight patients (10.7%) had 10 episodes of pneumoperitoneum. Six of these eight patients had asymptomatic pneumoperitoneum from a known etiology: four had undergone abdominal surgery for catheter placement the prior week and two had catheter manipulation immediately preceding the x-ray. One patient had three episodes of pneumoperitoneum: one after catheter placement and two not associated with a known etiology for pneumoperitoneum while on the cycler. One patient had a surgically confirmed colonic perforation with a large pneumoperitoneum and peritonitis.(ABSTRACT TRUNCATED AT 250 WORDS)