Opioid analgesia in necrotizing pancreatitis: Incidence and timing of a hidden crisis.

BACKGROUND: Rates of opioid usage during necrotizing pancreatitis (NP) disease course are unknown. We hypothesized that a significant number of NP patients were prescribed opioid analgesics chronically. METHODS: Single institution IRB-approved retrospective study of 230 NP patients treated between 2015 and 2019. RESULTS: Data were available for 198/230 (86%) patients. 166/198 (84%) were discharged from their index hospitalization with a prescription for an opioid. At the first clinic visit following hospitalization, 110/182 (60%) were using opioids. Six months after disease onset, 72/163 (44%) continued to require opioids. At disease resolution, 38/144 (26%) patients remained on opioid medications. The rate of active opioid prescriptions at six months after disease onset declined throughout the period studied from 68% in 2015 to 39% in 2019. CONCLUSIONS: Opioid prescriptions are common in NP. Despite decline over time, 1 in 4 patients remain on opioids at disease resolution. These data identify an opportunity to adjust analgesic prescription practice in NP patients.

Routine Gastric Decompression after Pancreatoduodenectomy: Treating the Surgeon?

BACKGROUND: The decision to routinely leave a nasogastric tube after pancreatoduodenectomy remains controversial. We sought to determine the impact of immediate nasogastric tube removal versus early nasogastric tube removal (<24 h) on postoperative outcomes. METHODS: A retrospective review of our institution's prospective ACS-NSQIP database identified patients that underwent pancreatoduodenectomy from 2015 to 2018. Outcomes were compared among patients with immediate nasogastric tube removal versus early nasogastric tube removal. RESULTS: A total of 365 patients were included in primary analysis (no nasogastric tube, n = 99; nasogastric tube removed <24 h, n = 266). Thirty-day mortality and infectious, renal, cardiovascular, and pulmonary morbidity were similar in comparing those with no nasogastric tube versus early nasogastric tube removal on univariable and multivariable analyses (P > 0.05). Incidence of delayed gastric emptying (11.1 versus 13.2%) was similar between groups. Patients with no nasogastric tube less frequently required nasogastric tube reinsertion (n = 4, 4%) compared to patients with NGT <24 h (n = 39, 15%) (OR = 3.83, 95% CI [1.39-10.58]; P = 0.009). CONCLUSION: Routine gastric decompression can be safely avoided after uneventful pancreaticoduodenectomy.

Optimal hepatobiliary scintigraphy for gallbladder dyskinesia.

BACKGROUND: The accuracy of hepatobiliary scintigraphy to assess gallbladder function remains controversial. National supply shortages of pharmaceutical-grade cholecystokinin led to the use of an oral fatty meal to stimulate gallbladder contraction during hepatobiliary scintigraphy. The goal of this study was to compare the predictive indices of cholecystokinin and fatty meal ingestion for stimulation of gallbladder contraction. METHODS: Patients evaluated with hepatobiliary iminodiacetic acid scan from 2014 to 2017 were reviewed and grouped based on testing stimulant (fatty meal versus cholecystokinin). Patients who later underwent cholecystectomy were selected for analysis. Hepatobiliary iminodiacetic acid results were correlated with surgical pathology and postoperative resolution of symptoms. Two-way statistical analysis was performed. RESULTS: A total of 359 patients underwent hepatobiliary iminodiacetic acid scan followed by cholecystectomy for biliary dyskinesia. Patients who received fatty meal stimulant (n = 86) were compared to those that received cholecystokinin (n = 273). Mean gallbladder ejection fraction during hepatobiliary iminodiacetic acid was 38% and 44% for the cholecystokinin and fatty meal groups, respectively, P = .073. Predictive metrics were not statistically different between groups with regard to pathology, symptomatic improvement, or accuracy. Symptomatic resolution (cholecystokinin-hepatobiliary iminodiacetic acid 78%, fatty meal-hepatobiliary iminodiacetic acid 68%; P = 0.058) and specificity (cholecystokinin-hepatobiliary iminodiacetic acid 26%, fatty meal-hepatobiliary iminodiacetic acid 44%, P = 0.417) were comparable in both testing groups. CONCLUSION: Stimulation of gallbladder contraction with a fatty meal during hepatobiliary iminodiacetic acid testing is a more affordable and reliable alternative to cholecystokinin for patients undergoing evaluation for gallbladder dysmotility.

Necrotizing Pancreatitis from Hypertriglyceridemia: More Severe Disease?

BACKGROUND: Necrotizing pancreatitis (NP) is caused by hypertriglyceridemia (HTG) in up to 10% of patients. Clinical experience suggests that HTG-NP is associated with increased clinical severity; objective evidence is limited and has not been specifically studied in NP. AIM: The aim of this study was to critically evaluate outcomes in HTG-NP. We hypothesized that patients with HTG-NP had significantly increased severity, morbidity, and mortality compared to patients with NP from other etiologies. METHODS: A case-control study of all NP patients treated at a single institution between 2005 and 2018 was performed. Diagnostic criteria of HTG-NP included a serum triglyceride level > 1000 mg/dL and the absence of another specific pancreatitis etiology. To control for differences in age, sex, and comorbidities, non-HTG and HTG patients were matched at a 4:1 ratio using propensity scores. Outcomes were compared between non-HTG and HTG patients. RESULTS: A total of 676 NP patients were treated during the study period. The incidence of HTG-NP was 5.8% (n = 39). The mean peak triglyceride level at diagnosis was 2923 mg/dL (SEM, 417 mg/dL). After propensity matching, no differences were found between non-HTG and HTG patients in CT severity index, degree of glandular necrosis, organ failure, infected necrosis, necrosis intervention, index admission LOS, readmission, total hospital LOS, or disease duration (P = NS). Mortality was similar in non-HTG-NP (7.1%) and HTG-NP (7.7%), P = 1.0. CONCLUSION: In this large, single-institution series, necrotizing pancreatitis caused by hypertriglyceridemia had similar disease severity, morbidity, and mortality as necrotizing pancreatitis caused by other etiologies.

Hepatic Steatosis After Neoadjuvant Chemotherapy for Pancreatic Cancer: Incidence and Implications for Outcomes After Pancreatoduodenectomy.

BACKGROUND: This study aimed to determine the incidence of new onset hepatic steatosis after neoadjuvant chemotherapy for pancreatic cancer and its impact on outcomes after pancreatoduodenectomy. METHODS: Retrospective review identified patients who received neoadjuvant chemotherapy for pancreatic adenocarcinoma and underwent pancreatoduodenectomy from 2013 to 2018. Preoperative computed tomography scans were evaluated for the development of hepatic steatosis after neoadjuvant chemotherapy. Hypoattenuation included liver attenuation greater than or equal to 10 Hounsfield units less than tissue density of spleen on noncontrast computed tomography and greater than or equal to 20 Hounsfield units less on contrast-enhanced computed tomography. RESULTS: One hundred forty-nine patients received neoadjuvant chemotherapy for a median of 5 cycles (interquartile range (IQR), 4-6). FOLFIRINOX was the regimen in 78% of patients. Hepatic steatosis developed in 36 (24%) patients. The median time from neoadjuvant chemotherapy completion to pancreatoduodenectomy was 40 days (IQR, 29-51). Preoperative biliary stenting was performed in 126 (86%) patients. Neoadjuvant radiotherapy was delivered to 23 (15%) patients. Female gender, obesity, and prolonged exposure to chemotherapy were identified as risk factors for chemotherapy-associated hepatic steatosis. Compared with control patients without neoadjuvant chemotherapy-associated hepatic steatosis, patients developing steatosis had similar rates of postoperative pancreatic fistula (8% (control) vs. 4%, p = 0.3), delayed gastric emptying (8% vs. 14%, p = 0.4), and major morbidity (11% vs. 15%, p = 0.6). Ninety-day mortality was similar between groups (8% vs. 2%, p = 0.08). CONCLUSION: Hepatic steatosis developed in 24% of patients who received neoadjuvant chemotherapy but was not associated with increased morbidity or mortality after pancreatoduodenectomy.

Comparison of skin closure techniques in patients undergoing open pancreaticoduodenectomy: A single center experience.

BACKGROUND: This study evaluated closure techniques and incisional surgical site complications (SSCs) and incisional surgical site infections (SSIs) after pancreaticoduodenectomy (PD). METHODS: Retrospective review of open PDs from 2015 to 2018 was performed. Outcomes were compared among closure techniques (subcuticular + topical skin adhesive (TSA); staples; subcuticular only). SSCs were defined as abscess, cellulitis, seroma, or fat necrosis. SSIs were defined according to the National Surgical Quality Improvement Program (NSQIP). RESULTS: Patients with subcuticular + TSA (n = 205) were less likely to develop an incisional SSC (9.8%) compared to staples (n = 139) (20.1%) and subcuticular (n = 74) (16.2%) on univariable analysis (P = 0.024). Multivariable analysis revealed no statistically significant difference in incisional SSC between subcuticular + TSA and subcuticular (P = 0.528); a significant difference remained between subcuticular + TSA and staples (P = 0.014). Unadjusted median length of stay (LOS) (days) was significantly longer for staples (9) vs. subcuticular (8) vs. subcuticular + TSA (7); P < 0.001. Incisional SSIs were evaluated separately according to the NSQIP definition. When comparing rates, the subcuticular + TSA group experienced lower incisional SSIs compared to the other two techniques (4.9% vs. 10.1%, 10.8%). However, this difference was not statistically significant by either univariable or multivariable analysis. CONCLUSIONS: Subcuticular suture + TSA reduces the risk of incisional SSCs when compared to staples alone after pancreaticoduodenectomy.

Two-electron spin correlations in precision placed donors in silicon.

Substitutional donor atoms in silicon are promising qubits for quantum computation with extremely long relaxation and dephasing times demonstrated. One of the critical challenges of scaling these systems is determining inter-donor distances to achieve controllable wavefunction overlap while at the same time performing high fidelity spin readout on each qubit. Here we achieve such a device by means of scanning tunnelling microscopy lithography. We measure anti-correlated spin states between two donor-based spin qubits in silicon separated by 16 ± 1 nm. By utilising an asymmetric system with two phosphorus donors at one qubit site and one on the other (2P-1P), we demonstrate that the exchange interaction can be turned on and off via electrical control of two in-plane phosphorus doped detuning gates. We determine the tunnel coupling between the 2P-1P system to be 200 MHz and provide a roadmap for the observation of two-electron coherent exchange oscillations.

Smoking and IPMN malignant progression.

BACKGROUND: Patients with intraductal papillary mucinous neoplasm (IPMN) are at risk for invasive pancreatic cancer. We aim to characterize the impact of smoking on IPMN malignant progression. METHODS: Patients undergoing pancreatic resection for IPMN (1991-2015) were retrospectively reviewed using a prospectively collected database. RESULTS: Of 422 patients identified, 324 had complete data for analysis; 55% were smokers. Smoking status did not impact IPMN malignant progression (smokers/non-smokers: 22%/18% invasive grade; p = 0.5). Smokers were younger than non-smokers at the time of IPMN diagnosis (63 versus 68 years; p = 0.001). This association also held in the invasive IPMN subgroup (65 versus 72 years, p = 0.01). Despite this observation, rate of symptoms at diagnosis, cancer stage, and median survival were the same between smokers and non-smokers. CONCLUSION: Although smoking is not associated with IPMN malignant progression, invasive IPMN is diagnosed at a younger age in smokers. These data suggest tobacco exposure may accelerate IPMN malignant progression.

High-Fidelity Single-Shot Singlet-Triplet Readout of Precision-Placed Donors in Silicon.

In this work we perform direct single-shot readout of the singlet-triplet states in exchange coupled electrons confined to precision-placed donor atoms in silicon. Our method takes advantage of the large energy splitting given by the Pauli-spin blockaded (2,0) triplet states, from which we can achieve a single-shot readout fidelity of 98.4±0.2%. We measure the triplet-minus relaxation time to be of the order 3 s at 2.5 T and observe its predicted decrease as a function of magnetic field, reaching 0.5 s at 1 T.

High-Fidelity Rapid Initialization and Read-Out of an Electron Spin via the Single Donor D(-) Charge State.

We demonstrate high-fidelity electron spin read-out of a precision placed single donor in silicon via spin selective tunneling to either the D(+) or D(-) charge state of the donor. By performing read-out at the stable two electron D(0)↔D(-) charge transition we can increase the tunnel rates to a nearby single electron transistor charge sensor by nearly 2 orders of magnitude, allowing faster qubit read-out (1 ms) with minimum loss in read-out fidelity (98.4%) compared to read-out at the D(+)↔D(0) transition (99.6%). Furthermore, we show that read-out via the D(-) charge state can be used to rapidly initialize the electron spin qubit in its ground state with a fidelity of F(I)=99.8%.

Radio frequency measurements of tunnel couplings and singlet-triplet spin states in Si:P quantum dots.

Spin states of the electrons and nuclei of phosphorus donors in silicon are strong candidates for quantum information processing applications given their excellent coherence times. Designing a scalable donor-based quantum computer will require both knowledge of the relationship between device geometry and electron tunnel couplings, and a spin readout strategy that uses minimal physical space in the device. Here we use radio frequency reflectometry to measure singlet-triplet states of a few-donor Si:P double quantum dot and demonstrate that the exchange energy can be tuned by at least two orders of magnitude, from 20 µeV to 8 meV. We measure dot-lead tunnel rates by analysis of the reflected signal and show that they change from 100 MHz to 22 GHz as the number of electrons on a quantum dot is increased from 1 to 4. These techniques present an approach for characterizing, operating and engineering scalable qubit devices based on donors in silicon.

Does preoperative cross-sectional imaging accurately predict main duct involvement in intraductal papillary mucinous neoplasm?

Main pancreatic duct (MPD) involvement is a well-demonstrated risk factor for malignancy in intraductal papillary mucinous neoplasm (IPMN). Preoperative radiographic determination of IPMN type is heavily relied upon in oncologic risk stratification. We hypothesized that radiographic assessment of MPD involvement in IPMN is an accurate predictor of pathological MPD involvement. Data regarding all patients undergoing resection for IPMN at a single academic institution between 1992 and 2012 were gathered prospectively. Retrospective analysis of imaging and pathologic data was undertaken. Preoperative classification of IPMN type was based on cross-sectional imaging (MRI/magnetic resonance cholangiopancreatography (MRCP) and/or CT). Three hundred sixty-two patients underwent resection for IPMN. Of these, 334 had complete data for analysis. Of 164 suspected branch duct (BD) IPMN, 34 (20.7%) demonstrated MPD involvement on final pathology. Of 170 patients with suspicion of MPD involvement, 50 (29.4%) demonstrated no MPD involvement. Of 34 patients with suspected BD-IPMN who were found to have MPD involvement on pathology, 10 (29.4%) had invasive carcinoma. Alternatively, 2/50 (4%) of the patients with suspected MPD involvement who ultimately had isolated BD-IPMN demonstrated invasive carcinoma. Preoperative radiographic IPMN type did not correlate with final pathology in 25% of the patients. In addition, risk of invasive carcinoma correlates with pathologic presence of MPD involvement.

Detection and measurement of spin-dependent dynamics in random telegraph signals.

A quantum point contact was used to observe single-electron fluctuations of a quantum dot in a GaAs heterostructure. The resulting random telegraph signals (RTS) contain statistical information about the electron spin state if the tunneling dynamics are spin dependent. We develop a statistical method to extract information about spin-dependent dynamics from RTS and use it to demonstrate that these dynamics can be studied in the thermal energy regime. The tunneling rates of each spin state are independently measured in a finite external magnetic field. We confirm previous findings of a decrease in overall tunneling rates for the spin excited state compared to the ground state as an external magnetic field is increased.

Pancreatic enucleation: improved outcomes compared to resection.

INTRODUCTION: Pancreatic enucleation is associated with a low operative mortality and preserved pancreatic parenchyma. However, enucleation is an uncommon operation, and good comparative data with resection are lacking. Therefore, the aim of this analysis was to compare the outcomes of pancreatic enucleation and resection. MATERIAL AND METHODS: From 1998 through 2010, 45 consecutive patients with small (mean, 2.3 cm) pancreatic lesions underwent enucleation. These patients were matched with 90 patients undergoing pancreatoduodenectomy (n = 38) or distal pancreatectomy (n = 52). Serious morbidity was defined in accordance with the American College of Surgeons-National Surgical Quality Improvement Program. Outcomes were compared with standard statistical analyses. RESULTS: Operative time was shorter (183 vs. 271 min, p < 0.01), and operative blood loss was significantly lower (160 vs. 691 ml, p < 0.01) with enucleation. Fewer patients undergoing enucleation required monitoring in an intensive care unit (20% vs. 41%, p < 0.02). Serious morbidity was less common among patients who underwent enucleation compared to those who had a resection (13% vs. 29%, p = 0.05). Pancreatic endocrine (4% vs. 17%, p = 0.05) and exocrine (2% vs. 17%, p < 0.05) insufficiency were less common with enucleation. Ten-year survival was no different between enucleation and resection. CONCLUSION: Compared to resection, pancreatic enucleation is associated with improved operative as well as short- and long-term postoperative outcomes. For small benign and premalignant pancreatic lesions, enucleation should be considered the procedure of choice when technically appropriate.

Measurement of the spin relaxation time of single electrons in a silicon metal-oxide-semiconductor-based quantum dot.

We demonstrate direct detection of individual electron spin states, together with measurement of spin relaxation time (T1), in silicon metal-oxide-semiconductor-based quantum dots (QD). Excited state spectroscopy of the QD has been performed using a charge-sensing technique. T1 of single spin excited states has been done in the time domain by a pump-and-probe method. For an odd and an even number of electrons, we found a magnetic field dependent and invariant T1, respectively.

Very high serum CA 19-9 levels: a contraindication to pancreaticoduodenectomy?

AIM: To assess the outcome of patients with resectable pancreatic adenocarcinoma (PA) associated with high serum CA 19-9 levels. METHODS: From 2000 to 2007, 344 patients underwent pancreatoduodenectomy for PA. Fifty-three patients (elevated group) had preoperatively elevated serum CA 19-9 levels (>400 IU/ml) after resolution of obstructive jaundice. Of these, 27 patients had high levels (400-899 IU/ml (HL)) and 26 patients had very high levels >or=900 IU/ml (VHL). Fifty patients with normal preoperative serum CA 19-9 levels (<37 IU/ml) comprised the control group. RESULTS: Median survival of the control group (n = 50) versus elevated group (n = 53) was 22 versus 15 months (p = 0.02) and overall 3-year survival was 32% versus 14% (p = 0.03). There was no statistical difference in the median and 3-year overall survival between patients with HL and VHL. Patients in the elevated group who normalized their CA 19-9 levels after surgery (n = 11) had a survival equivalent to patients in the control group. CONCLUSIONS: Patients who normalized their CA19-9 levels postoperatively had equivalent survival to patients with normal preoperative CA 19-9 levels. Preoperative serum CA 19-9 level by itself should not preclude surgery in patients who have undergone careful preoperative staging.

Perforated Amyand's hernia.

We report a case of acute perforated appendicitis in an incarcerated inguinal hernia, termed an Amyand's hernia. Although perforated appendicitis within an incarcerated inguinal hernia is uncommon, with a published incidence of 0.13%, its clinical presentation varies considerably, depending on the extent of periappendicular inflammation and the presence or absence of peritoneal contamination.