Fine catheter peritoneal cytology for the acute abdomen: a randomized, controlled trial

Peritoneal cytology for suspected acute appendicitis: an economic evaluation

Suspected acute appendicitis is a common reason for surgery. Unfortunately, diagnosis is not always simple and, in recent years, considerable attention has been devoted to developing better diagnostic techniques. Peritoneal cytology is one such technique. It is simple, minimally invasive, and has been established as clinically effective. This paper reports on an economic evaluation of peritoneal cytology, carried out at Wellington Hospital, New Zealand. The analysis is based on two trials totalling 192 patients. The perspective taken initially is that of a hospital financial manager, seeking to minimise costs. In the first trial, there was a marginal increase in overall cost per person presenting with suspected acute appendicitis, from using the test. In the second, there was a reduction. In both trials there were significant health benefits--unnecessary operations were avoided, and necessary operations done more quickly. Also, the practice developed, in the second trial, of sending patients home immediately following a negative test result. This further increased savings. We then discuss the results from a broader perspective. We conclude that the additional personal benefits--less time convalescing, and lower mortality, on average--ensure that the benefits outweigh the costs of the test.

Peritoneal aspiration cytology as a diagnostic aid in acute appendicitis

A total of 110 consecutive patients presenting to one surgical firm with suspected acute appendicitis underwent peritoneal aspiration cytology. Aspiration was successful in 108 patients and 44 were positive. Patients with a positive result underwent emergency surgery; 42 had histologically proven acute appendicitis and two peritonitis of other causes. Seven patients with a negative result underwent appendicectomy; four had acute appendicitis and three a normal appendix. Peritoneal aspiration cytology had a sensitivity for acute appendicitis of 91 per cent and a specificity of 94 per cent. The positive predictive value of the test was 95 per cent and the negative predictive value 94 per cent. The negative appendicectomy rate was 10 per cent overall and 11 per cent in women of reproductive age. Peritoneal aspiration cytology is a useful diagnostic test in the management of patients with suspected acute appendicitis.

Correlation of peritoneal aspiration cytology with acute appendicitis

Fifty-one patients in whom a clinical diagnosis of acute appendicitis had been made underwent peritoneal aspiration cytology (PAC). Thirty-six had a positive result, 11 had a negative result and aspiration failed in four cases. All patients had an appendicectomy and the histological findings were correlated with the PAC results. Thirty-five of the 36 patients with a positive PAC had histologically proven appendicitis. Seven of the 11 patients with a negative result had normal appendices. The sensitivity of PAC for acute appendicitis was 85% and the specificity was 70%. The positive predictive value was found to be 97% and the negative predictive value 60%. Peritoneal aspiration cytology is a useful aid in the diagnosis of acute appendicitis however, a negative result does not exclude this diagnosis.

Diagnosis of metastatic carcinoma of stomach using fine catheter aspiration cytology

The value of fine catheter aspiration cytology organs of the peritoneal cavity in the diagnosis of a metastatic carcinoma is illustrated by this case report. The finding of unequivocal malignant cells was quite unexpected and led to an investigation of the gastrointestinal tract which demonstrated a primary carcinoma in the stomach. This was further confirmed on a biopsy of the tumor and cell block preparations of aspirated material on which immunostaining was done and which further substantiated the light microscopic cytohistologic diagnosis. The findings presented in this article further emphasize the value of fine catheter aspiration cytology in not only identifying tumor type or predicting the source of the primary but also in managing patients admitted with abdominal pain as an emergency who may be saved from an unnecessary laparotomy which would have otherwise been done for a diagnosis.

Diagnosis of metastatic pleomorphic giant cell carcinoma of the pancreas using fine catheter aspiration cytology

The value of fine catheter aspiration cytology in the diagnosis of metastatic tumours is illustrated by a case of pleomorphic giant cell carcinoma of the pancreas which had metastasized to the peritoneal cavity. The finding of unequivocal malignant cells obviated the need for further diagnostic procedures. Electron microscopy and immunostaining further substantiated the light microscopic cytodiagnosis and identified the tumour type and source of the primary tumour. Furthermore, subsequent cell block preparation from the aspirated material demonstrated the histological features of this tumour.

Strategies for reducing inappropriate laparotomy rate in the acute abdomen

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The acute abdomen: the role of laparoscopy

The ability to improve surgical decision-making in the acute abdomen using selective laparoscopy is now established. When the decision to operate is uncertain laparoscopy not only identifies those patients who do not require laparotomy, but also reveals those who need surgery which might otherwise have been delayed. Furthermore, the high error rates in diagnosing acute appendicitis in young women provides overwhelming support to the current view that all women with suspected appendicitis should undergo laparoscopy before appendicectomy, irrespective of clinical 'certainty'. Improvements in the management of the acute abdomen can also be achieved by other techniques such as computer-assisted diagnosis (McAdam et al, 1990) and peritoneal cytology (Stewart et al, 1988), and a combination of these with selective laparotomy would be appropriate. Initial patient assessment using a structured proforma would appear to be one of the most significant factors in the improvement of diagnostic accuracy associated with the use of computers (Gunn, 1976), and their combination with a policy of selective laparoscopy has been shown to be beneficial (Paterson-Brown et al, 1989). The ability to detect which patients are likely to benefit from laparoscopy by performing peritoneal cytology first (Vipond et al, 1990) has been shown to be helpful in reducing the number of patients who undergo a 'negative laparoscopy' (Baigrie et al, 1990). It is now time for laparoscopy to return to the bosom of general surgery from where it was conceived almost a century ago. When it does, as the developments in laparoscopic cholecystectomy would predict it will, so surgeons in training must take the earliest opportunity to become as familiar and proficient with the technique as their gynaecological colleagues have done, even if this means attending the gynaecological operating lists to do so. It is only then that the undoubted benefits of laparoscopy will be spread more widely in general surgery and particularly for the patient with acute abdominal pain.

Role of fine catheter peritoneal cytology and laparoscopy in the management of acute abdominal pain

Laparoscopy and fine catheter peritoneal cytology (FCPC) have been advocated as aids in the assessment of acute abdominal pain. In all, 411 patients admitted to a district general hospital during a 10-month period were managed using a standard protocol incorporating these techniques. After initial assessment by a surgical registrar, 151 patients were excluded from further progress through the protocol (age less than 16 years, definite diagnosis made or contraindication to FCPC. The remaining 260 patients were placed in one of four management groups: (A) urgent operation (23 patients); (B) 'look and see' (40 patients); (C) 'wait and see' (59 patients); (D) urgent operation not indicated (138 patients). Eighty-eight of 99 patients (88 per cent) in groups B and C, where the need for operation was uncertain, underwent successful FCPC and 39 patients (39 per cent) underwent laparoscopy. In these patients the initial registrar management decision proved to be incorrect in 33 cases (33 per cent), but by following the protocol the number of management errors actually made was reduced to 13 (13 per cent, P less than 0.001). This would have been reduced to 8 per cent if the protocol had not been violated in five patients. This study demonstrates the effectiveness of a protocol using FCPC and laparoscopy to improve the management of patients with acute abdominal pain.

Modern aids to clinical decision-making in the acute abdomen

Acute abdominal pain continues to provide not only a large workload for the general surgeon but also many diagnostic and management problems. Many different techniques have been introduced over the past two decades to help in the management of the acute abdomen and this review considers their relative claims to become incorporated into the process of clinical decision-making. The evidence in support of formally structured patient interview pathways with or without computer-aided diagnostic programs is now overwhelming and should become routine. Both laparoscopy and peritoneal cytology have an important role to play in the management of patients in whom the decision to operate is in doubt, and a combination of the two would be complementary. Ultrasonography has become increasingly popular for investigating the acute abdomen, and results from specialist centres are impressive. However, the problems of operator variation and the difficulties in providing a 24-h service will probably prevent it from becoming a first-line investigation in most hospitals. Although plain radiography has been available for many years, its routine use in the management of the acute abdomen remains controversial. Recent studies have confirmed that contrast radiography is an important adjunct to decision-making, particularly in the management of large bowel obstruction, and there is increasing evidence to support its use in suspected small bowel obstruction, perforated peptic ulcer and acute diverticular disease.

Evaluation of fine catheter aspiration cytology of the peritoneum as an adjunct to decision making in the acute abdomen

Fine catheter aspiration cytology of the peritoneal cavity was performed successfully in 61 patients admitted with acute abdominal pain. Aspirates were examined microscopically and the percentage of neutrophils in the specimen counted. In patients in whom the clinical need for operation was certain (n = 25) all patients required surgery and the peritoneal neutrophil count was greater than 50 per cent. In patients in whom the clinical need for operation was uncertain (n = 36) 19 patients required operation: the peritoneal neutrophil count was greater than 50 per cent in 18 and in one patient with ectopic pregnancy fresh blood was aspirated. Of the 17 patients not requiring operation the peritoneal neutrophil count was less than 10 per cent in 15 and greater than 50 per cent in two patients (both had acute pelvic inflammatory disease). This study confirms peritoneal cytology as a useful adjunct to decision making in those patients with acute abdominal pain in whom the decision to operate is in doubt.