Muhammad Rizwan Khan
Aga Khan University
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BMC Surgery | 2011
Muhammad Rizwan Khan; Hassaan Bari; Syed Nabeel Zafar; Syed Ahsan Raza
BackgroundColorectal cancer (CRC) is a major source of morbidity and mortality in the elderly population and surgery is often the only definitive management option. The suitability of surgical candidates based on age alone has traditionally been a source of controversy. Surgical resection may be considered detrimental in the elderly solely on the basis of advanced age. Based on recent evidence suggesting that age alone is not a predictor of outcomes, Western societies are increasingly performing definitive procedures on the elderly. Such evidence is not available from our region. We aimed to determine whether age has an independent effect on complications after surgery for colorectal cancer in our population.MethodsA retrospective review of all patients who underwent surgery for pathologically confirmed colorectal cancer at Aga Khan University Hospital, Karachi between January 1999 and December 2008 was conducted. Using a cut-off of 70 years, patients were divided into two groups. Patient demographics, tumor characteristics and postoperative complications and 30-day mortality were compared. Multivariate logistic regression analysis was performed with clinically relevant variables to determine whether age had an independent and significant association with the outcome.ResultsA total of 271 files were reviewed, of which 56 belonged to elderly patients (≥ 70 years). The gender ratio was equal in both groups. Elderly patients had a significantly higher comorbidity status, Charlson score and American society of anesthesiologists (ASA) class (all p < 0.001). Upon multivariate analysis, factors associated with more complications were ASA status (95% CI = 1.30-6.25), preoperative perforation (95% CI = 1.94-48.0) and rectal tumors (95% CI = 1.21-5.34). Old age was significantly associated with systemic complications upon univariate analysis (p = 0.05), however, this association vanished upon multivariate analysis (p = 0.36).ConclusionOlder patients have more co-morbid conditions and higher ASA scores, but increasing age itself is not independently associated with complications after surgery for CRC. Therefore patient selection should focus on the clinical status and ASA class of the patient rather than age.
BMC Surgery | 2011
Syed Nabeel Zafar; Muhammad Rizwan Khan; Rushna Raza; Muhammad N Khan; Mahwash Kasi; Ammar Rafiq; Omer Jamy
BackgroundBiliary-enteric anastomosis (BEA) is a common surgical procedure performed for the management of biliary obstruction or leakage that results from a variety of benign and malignant diseases. Complications following BEA are not rare. We aimed to determine the incidence and the factors associated with early complications occurring after BEA for benign diseases.MethodsWe reviewed the medical records of all patients who underwent BEA for benign diseases at our institution between January 1988 and December 2009. The primary outcome was early post operative complication. Logistic regression analysis was done to identify factors predicting the occurrence of complications.ResultsRecords of 79 patients were reviewed. There were 34 (43%) males and 45 (57% females). Majority (53%) had choledocholithiasis with impacted stone or distal stricture, followed by traumatic injury to the biliary system (33%). Thirty-four patients (43%) underwent a hepaticojejunostomy, 19 patients (24%) underwent a choledochojejunostomy, and choledochoduodenostomy was performed in 26 patients (33%). Early complications occurred in 39 (49%) patients - 41% had local complications and 25% had systemic complications. Most frequent complications were wound infection (23%) and bile leak (10%). Four (5%) patients died. On multivariate analysis, low serum albumin level (odds ratio = 16, 95% CI = 1.14-234.6) and higher ASA levels (odds ratio = 7, 95% CI: 1.22-33.34) were the independent factors predicting the early complications following BEA.ConclusionsHalf of the patients who underwent BEA for benign diseases had complications in our population. This high incidence may be explained by the high incidence of hypoalbuminemia and the high-risk group who underwent operation.
Journal of Surgical Research | 2012
Muhammad Rizwan Khan; Rushna Raza; Syed Nabeel Zafar; Faisal Shamim; Syed Ahsan Raza; Khawaja Muhammad Inam Pal; Hasnain Zafar; Rehman Alvi; Tabish Chawla; Rizwan Azmi
BACKGROUND Intraperitoneal local anesthetics have been shown to improve postoperative pain after laparoscopic cholecystectomy (LC). However, the choice of local anesthetic agent is debatable. We compared the analgesic efficacy of intraperitoneal lignocaine (lidocaine) versus bupivacaine after elective LC. METHODS We conducted a double-blind, randomized, controlled trial. We randomized consecutive patients undergoing LC into two groups. Group L received 10 mL 2% lignocaine (lidocaine), whereas Group B received 10 mL 0.5% bupivacaine, each diluted in 10 mL normal saline. All patients underwent standard perioperative anesthesia and analgesia protocol. We assessed patients at 0, 4, 8, 12, and 24 h postoperatively for pain using the visual analogue scale and verbal rating scale, and the need for additional analgesic medications. RESULTS We analyzed a total of 206 patients: 106 in Group L and 100 in Group B. Demographic details were similar between groups (P > 0.05). Abdominal pain decreased significantly with time in both groups, with a similar mean response profile (P < 0.001). There was no statistically significant difference between groups with regard to abdominal or shoulder pain by both visual analogue scale and verbal rating scale at all five time intervals (P > 0.05). There was also no significant difference in the side effect profile of both drugs (P > 0.05). A lower proportion of patients in Group B required additional narcotic analgesia (87%) compared with Group L (94%). This difference was marginally significant (P = 0.057). CONCLUSIONS Bupivacaine and lignocaine (lidocaine) are both safe and equally effective at decreasing postoperative pain after LC.
Saudi Journal of Gastroenterology | 2010
Rajab Ali; Muhammad Rizwan Khan; Turab Pishori; Mohammad Tayeb
Background/Aim: The role of laparoscopic appendectomy is still not well defined in the literature. This study was conducted to evaluate the feasibility of laparoscopic appendectomy at a university hospital in a developing country. Patients and Methods: Patients undergoing laparoscopic appendectomy (LA) from August 2002 to August 2006 were identified. For each case, a control was selected from patients undergoing open appendectomy (OA) during the same year by systematic sampling. The groups were compared in terms of duration of surgery, requirement of narcotic analgesia, length of hospital stay, postoperative complications and the overall cost for each patient. Results: A total of 68 patients underwent laparoscopic appendectomy during the study period. Median duration of surgery was 82 minutes in LA group and 70 minutes in OA group (P < 0.001). Forty-five patients in LA group and 64 in OA group required narcotic analgesia (P < 0.001). Median length of hospital stay (P = 0.672) and postoperative complications (P = 0.779) were comparable in both groups. Median cost of hospital stay was Pakistani Rupees (PKR) 47121/in LA group and PKR 39318/in OA group, the difference being significant (P = 0.001). Conclusions: Laparoscopic appendectomy is feasible in developing countries with similar postoperative outcome and less requirement of narcotic analgesia. The duration of surgery and overall cost were significantly higher and efforts should be made to develop expertise and reduce operative time with resultant decrease in cost. Development of standardized protocols for discharge of patients from the hospital after LA may further reduce the cost and benefit patients in developing countries.
Journal of Medical Case Reports | 2010
Muhammad Rizwan Khan; Rashida Ahmed; Taimur Saleem
IntroductionMucinous cystadenoma is a type of mucocele of the appendix that is rarely encountered in clinical practice. Dogmatic consensus on the optimal surgical modus operandi of appendicular mucocele is lacking in the literature and this remains a subject of controversy. There is little agreement with regard to the best procedure (right hemicolectomy versus appendectomy) or the best surgical approach (laparoscopic versus laparotomy).Case presentationWe report the case of a 70-year-old Asian woman from Karachi who presented with pain in the right iliac fossa for 15 days. On physical examination, a mobile and firm mass was palpable in the right iliac fossa. A colonoscopy was performed which showed external compression of the cecum. A biopsy of the mucosa was normal. Computed tomography scan showed a mucocele of the appendix with minimal periappendiceal fat stranding. She underwent an initial diagnostic laparoscopy to evaluate any mucin spillage in the peritoneal cavity. Once no spillage was identified, an open appendectomy was then performed. Intra-operatively, a frozen section of the appendiceal sample was sent to ascertain the need for an extension of surgery to a right hemicolectomy. Absence of any malignancy on the frozen section obviated the need for a surgical extension. The final histopathological examination showed a mucinous cystadenoma of the appendix. The patient was symptom-free at one year after surgery.ConclusionIt is important to distinguish between mucinous cystadenomas and mucinous cystadenocarcinomas. However, this distinction remains elusive in the pre-operative setting. A simple appendectomy using an intra-operative frozen section appears to be a reasonable surgical approach for selected cases with an intact mucocele of the appendix. However, long-term follow-up is warranted in such patients to evaluate the risks of using this approach.
World Journal of Emergency Surgery | 2012
Muhammad Rizwan Khan; Sameer ur Rehman
Sigmoid volvulus is a rare surgical complication occurring in pregnancy and puerperium. Only 84 cases of sigmoid volvulus in pregnancy have been reported in the English literature so far. We have reviewed the available literature on this subject and present another case recently managed at our institution. The available literature suggests that over the years, there has been an improvement in the maternal and fetal outcome for this critical condition, but delay in presentation and a further delay in diagnosis remain a challenge for the treating physicians. Our patient was a 30-week pregnant lady, who presented late with 6 days history of abdominal pain, distension and absolute constipation. She had evidence of multi-organ dysfunction at presentation due to complicated sigmoid volvulus. She was resuscitated and surgical exploration revealed gangrenous large bowel. Bowel resection with diverting ileostomy was performed, but she succumbed to the septic shock due to late presentation. Acute surgical pathology may be overlooked in pregnant patients due to reluctance in radiological workup and a high index of suspicion is essential for enhanced outcome. There is a need to increase the awareness amongst the obstetricians and general practitioners. Early diagnosis and referral and timely surgical intervention could significantly improve the outcome of this surgical and obstetric catastrophe.
Cases Journal | 2009
Muhammad Rizwan Khan; Saad Ajmal; Taimur Saleem
Adrenal cysts are rare clinical entities that can present as acute abdomen through rupture and internal hemorrhage as well as chronic symptoms such as gastrointestinal disturbances. A 20-year-old girl presented to our hospital with a 4-years history of abdominal pain and diarrhea. Ultrasound of the abdomen revealed a cystic area measuring 10 × 10 cm between the spleen and left kidney. Computed tomography scan showed a large cystic, homogeneous mass measuring 12.8 × 9.5 × 9.4 cm in the left hypochondrium with most likely origin from the left adrenal gland. Limited work up for hormone hypersecretion was negative. The patient was then encountered in the emergency room with an acute abdomen secondary to intracystic hemorrhage. A laparotomy with left adrenalectomy was performed. Final pathology showed a benign adrenal endothelial cyst. Post-operatively, the patients long standing complaints of diarrhea and abdominal pain completely resolved. Surgical resection appears a safe and reasonable management strategy in a patient with intracystic hemorrhage of adrenal cyst.
Saudi Journal of Gastroenterology | 2008
Mohammad Tayeb; Muhammad Rizwan Khan; Nazia Riaz
Background/Aims: Although laparoscopic cholecystectomy (LC) has become the procedure of choice for cholelithiasis in the general population, many consider cirrhosis as a relative or absolute contraindication for laparoscopic surgery. The aim of this study was to confirm the safety of LC in cirrhotic patients in our set-up. Materials and Methods: This is a retrospective case series including all the patients with cirrhosis who underwent LC for gallstones from January 2000 to December 2006 at our institution. Data were analyzed for Child class, indication for surgery, hospital stay, and procedure-related morbidity and mortality. Results are given as mean ± standard deviation. Results: Thirty patients, including 21 females (median age: 42 years) underwent LC during the study period. There was no operative mortality. Twenty-four patients belonged to Child class A and 6 belonged to Child class B. Mean operative time was 80 ± 26 min. There was no incidence of bile duct injury, but two patients (6.7%) required conversion to open procedure. Mean hospital stay was 3 ± 2.7 days. Postoperative morbidity was observed in seven patients, including postoperative deterioration of liver function in 2, worsening of ascites in 2 and pneumonia, and port-site infection in 1. Two patients had significant drop in hemoglobin requiring blood transfusion. Conclusions: Cirrhosis is not a contraindication for LC and it can be performed safely in compensated cirrhotic patients with acceptable morbidity and mortality.
International Journal of Surgery | 2011
Muhammad Rizwan Khan; Syed Ahsan Raza; Zubair Ahmad; Sana Naeem; Shahid Pervez; Anwar Ali Siddiqui; Mushtaq Ahmed; Rizwan Azami
The gallbladder specimens of patients who underwent cholecystectomy for symptomatic gallstones between 2003 and 2005 were evaluated for the presence of Intestinal Metaplasia. (IM) and its risk factors. IM was positive in 39% of 293 patients tested, and in the comparative analysis of 114 metaplasia positive versus 179 negative patients, a high risk was found in patients who were 60 years or older [adjusted odds ratio (aOR) = 3.0, 95% confidence interval (CI): 1.5, 6.2]. Other factors with aOR greater than 1 were moderate to excessive use of chilies (1.8) and ethnic origin of North India (1.7). Screening method has yet to be devised for early detection of gallbladder cancer by identifying metaplastic lesions early in life. We believe that large geographic variation and lifestyle environmental factors associated with the development of gallbladder metaplasia and cancer mortality are concealed in our study that needs to be further explored.
Journal of Medical Case Reports | 2012
Muhammad Rizwan Khan; Sameer ur Rehman
IntroductionMirizzi’s syndrome is a rarely observed disorder that presents with obstructive jaundice. The condition is caused by a stone impacted in the gall bladder neck or cystic duct that impinges on the common hepatic duct, with or without a cholecystocholedochal fistula. The condition is often confused with other serious conditions such as hilar cholangiocarcinoma, which present with similar clinical and imaging findings, and a pre-operative diagnosis may be a serious challenge.Case presentationWe present the case of a 44-year-old Asian man with Mirizzi’s syndrome who was initially diagnosed as having cholangiocarcinoma based on his clinical presentation, raised cancer antigen 19–9 levels and radiological findings. Our patient was diagnosed as having Mirizzi’s syndrome intra-operatively and subsequently a cholecystectomy was performed with restoration of biliary drainage. Careful clinical assessment during surgery with the help of intra-operative frozen section helped in establishing the definitive diagnosis and altered the surgical procedure for our patient.ConclusionsPre-operative diagnosis of Mirizzi’s syndrome could be challenging as the clinical, biochemical and radiological presentation is similar to other conditions causing obstructive jaundice such as choledocholithiasis, bile duct stricture or cholangiocarcinoma. A high index of suspicion and careful surgical assessment may help in establishing a diagnosis and alter the clinical course for our patient.