A right-to-left or bidirectional ductal shunt in preterm neonates: grave implication?

We delineate the natural history of a right-to-left or bidirectional (RL/BD) patent ductus arteriosus (PDA) in preterm infants and compare outcomes of an RL/BD and a left-to-right (LR) ductal shunt. We performed a retrospective chart review of preterm infants (< 32 weeks), who, between 2 and 30 days of age, had an RL/BD PDA > 1.5 mm (study group; N = 74) or an LR PDA (N = 87) on echocardiogram (ECHO). In the study group, 27% of infants who were of significantly lower gestational age and birth weight had a "prolonged" RL/BD PDA on two or more ECHOs. Infants with RL/BD PDA required significantly greater surfactant (98.6% versus 94.2%) and less PDA therapy (27% versus 92%) and had higher mortality (48.6% versus 21.8%) compared with those with LR PDA. On regression analysis, lower gestation (odds ratio [OR] 1.45; 95% confidence interval [CI]: 1.15 to 1.83) and RL/BD PDA (OR 4.74; 95% CI: 2.18 to 10.3) were significantly associated with mortality. The independent association between an RL/BD PDA shunt and mortality warrants further investigation. Insights into the etiology of pulmonary hypertension may optimize outcomes in this population.     

Increased susceptibility of spontaneously hypertensive rats to ventricular tachyarrhythmias in early hypertension

Key points

• Hypertension is a risk factor for sudden cardiac death caused by ventricular tachycardia and fibrillation.
• Whether hypertension in its early stage is associated with an increased risk of ventricular tachyarrhythmias is not known.
• Based on experiments performed at the cellular and whole heart levels, we show that, even early in chronic hypertension, the hypertrophied and fibrotic ventricles of spontaneously hypertensive rats aged 5 to 6 months have already developed increased stress‐induced arrhythmogenicity, and this increased susceptibility to ventricular arrhythmias is primarily a result of tissue remodelling rather than cellular electrophysiological changes.
• Our findings highlight the need for early hypertension treatment to minimize myocardial fibrosis, ventricular hypertrophy, and arrhythmias.

Abstract

Hypertension is a risk factor for sudden cardiac death caused by ventricular tachycardia and fibrillation (VT/VF). We hypothesized that, in early hypertension, the susceptibility to stress‐induced VT/VF increases. We compared the susceptibility of 5‐ to 6‐month‐old male spontaneously hypertensive rats (SHR) and age/sex‐matched normotensive rats (NR) to VT/VF during challenge with oxidative stress (H₂O₂; 0.15 mmol l⁻¹). We found that only SHR hearts exhibited left ventricular fibrosis and hypertrophy. H₂O₂ promoted VT in all 30 SHR but none of the NR hearts. In 33% of SHR cases, focal VT degenerated to VF within 3 s. Simultaneous voltage‐calcium optical mapping of Langendorff‐perfused SHR hearts revealed that H₂O₂‐induced VT/VF arose spontaneously from focal activations at the base and mid left ventricular epicardium. Microelectrode recording of SHR hearts showed that VT was initiated by early afterdepolarization (EAD)‐mediated triggered activity. However, despite the increased susceptibility of SHR hearts to VT/VF, patch clamped isolated SHR ventricular myocytes developed EADs and triggered activity to the same extent as NR ventricular myocytes, except with larger EAD amplitude. During the early stages of hypertension, when challenged with oxidative stress, SHR hearts showed an increased ventricular arrhythmogenicity that stems primarily from tissue remodelling (hypertrophy, fibrosis) rather than cellular electrophysiological changes. Our findings highlight the need for early hypertension treatment to minimize myocardial fibrosis, ventricular hypertrophy, and arrhythmias.

Abbreviations

AP

action potential

APD

action potential duration

APD₉₀

action potential at 90% duration

CaMKII

calcium/calmodulin‐dependent protein kinase II

CaT

calcium transient

CaTD₉₀

calcium transient at 90% duration

CI

confidence interval

DBP

diastolic blood pressure

EAD/DAD

early/delayed after‐depolarization

HR

heart rate

ICC

interclass correlation

I_Ca,L

L‐type calcium current

I_Ks

slow delayed rectifier potassium current

I_Na

sodium current

I_to

transient outward potassium current

IVS(d,s) interventricular septum thickness (during diastole

during systole)

LV

left ventricle

LVEF

left ventricular ejection fraction

LVFS

left ventricular fractional shortening

LVH

left ventricular hypertrophy

LVID(d,s) left ventricular internal diameter (during diastole

during systole)

MV

mitral valve

NR

normotensive rats

PA peak vel

pulmonary artery peak velocity

(P)CL

(pacing) cycle length

PW

posterior wall

P‐ECG

pseudo‐electrocardiogram

RV

right ventricle

RWT

relative wall thickness

SHR

spontaneously hypertensive rats

SHHF

spontaneously hypertensive heart failure

SBP

systolic blood pressure

VT/VF

ventricular tachycardia and fibrillation

     

Immunoreactivity of Entamoeba histolytica antigens with sera from amoebic patients

Immune sera from 15 patients with cured amoebic liver abscess were used to recognise the antigens of Entamoeba histolytica (HMI) by immunoblotting. The amoebic proteins most frequently recognised by sera from patients with cured amoebic liver abscess had molecular masses of 8, 13, 18, 22, 29, 38, 45, 67 and 94 kDa. Six plasma membrane-associated amoebic proteins of molecular mass 29, 38, 45–67 complex, 85 and 94 kDa were strongly recognised by such sera. Two plasma membrane-associated antigens of 108 and 129 kDa were not recognised by any sera. None of the crude or plasma membrane-associated antigens were recognised by sera from five patients of idiopathic ulcerative colitis, five patients of persistent giardiasis and five normal healthy subjects. Identifiction of such antigens, especially plasma membrane-associated antigens may pave a way to develop specific diagnostic and immunoprotective agents.     

Evaluating the influence of prostate-specific antigen kinetics on metastasis in men with PSA recurrence after partial gland therapy

Purpose

Although current Delphi Consensus guidelines do not recommend a specific definition of biochemical recurrence after partial gland therapy, these guidelines acknowledge that serial prostate-specific antigen (PSA) tests remain the best marker for monitoring disease after treatment. The purpose of this study was to determine whether PSA velocity at failure per the Phoenix (nadir + 2 ng/mL) definition is associated with metastasis and prostate cancer-specific mortality (PCSM) in a cohort of patients who experienced PSA failure after partial gland therapy.

Novel method of pancreatojejunal reconstruction after spontaneous closure of previous lateral pancreatojejunostomy

Lateral pancreatojejunostomy is a well-documented procedure for pain relief in chronic pancreatitis with a dilated main pancreatic duct. However, a number of patients develop recurrence of pain at variable intervals after a successful drainage procedure. A 40-year-old patient with tropical chronic pancreatitis developed recurrence of pain 13 years after a lateral pancreatojejunostomy. Investigation demonstrated a dilated main pancreatic duct. Re-exploration revealed a near complete closure of the previous lateral pancreatojejunostomy. A novel method of pancreatojejunal reconstruction was performed. Patient is pain-free after a follow-up of 18 months since surgery. The long-term status of lateral pancreatojejunostomy remains unclear. Our case documents, probably for the first time in published literature, a near total spontaneous closure of a previous lateral pancreatojejunostomy that was responsible for recurrence of pain. Our method of pancreatojejunal reconstruction adds to the armamentarium of the pancreatic surgeon.     

Use of continuous positive airway pressure during spinal anaesthesia in a patient with severe chronic obstructive pulmonary disease

We report the case of a patient with severe chronic obstructive pulmonary disease who underwent local resection of a carcinoma of the rectum under spinal anaesthesia. Although the patient was keen to avoid general anaesthesia and to have the operation under a spinal anaesthetic, pre-operative assessment showed that he could not lie flat. As the surgical procedure required the patient to be in the lithotomy position, ideally with a head-down tilt, it was hoped that continuous positive airway pressure with a facemask during spinal anaesthesia might help him to tolerate the position comfortably. Continuous positive airway pressure at 7.5 cmH(2)O was successfully used to facilitate breathing during surgery under spinal anaesthesia. A combination of regional anaesthesia and continuous positive airway pressure via a facemask is easy to use and may be a useful option in the management of these challenging patients.     

Re-dosing of del Nido cardioplegia in adult cardiac surgery requiring prolonged aortic cross-clamp

Open in a separate window OBJECTIVESFew data exist on the use of del Nido cardioplegia in adults, specifically during operations requiring prolonged aortic cross-clamp. In this pilot study, we evaluate outcomes of patients undergoing surgery with cross-clamp time >3 h based on re-dosing strategy, using either full dose (FD; 1:4 blood to crystalloid ratio) or dilute (4:1 blood to crystalloid ratio) solution.METHODSConsecutive adult patients (>18 years) undergoing cardiac surgery from 2012 to 2018 with cross-clamp time >3 h were reviewed. Patients were excluded if del Nido cardioplegia was not used. Patients were categorized into FD or dilute groups based on re-dosing solution. Propensity score matching was used to control for baseline differences between groups. The primary endpoint was in-hospital mortality. Other outcomes examined included: postoperative mechanical support, arrhythmia, stroke, dialysis and cardiac function.RESULTSIncluded for analysis were 173 patients (115 male) with median age of 63.8 (interquartile range 53.9–73.1). Major comorbidities included diabetes (45), cerebrovascular disease (34), hypertension (131), atrial fibrillation (52) and previous cardiac surgery (83). There were 108 patients (62%) who received FD re-dosing, while 65 (38%) received dilute. A greater proportion of patients in the dilute group received retrograde delivery, for both induction (32/108 vs 39/65, P < 0.001) and re-dose (50/108 vs 53/65, P < 0.001). After propensity score matching, in-hospital mortality was not different between groups (6/48 vs 1/48, P = 0.131). There were no differences in rates of postoperative mechanical circulatory support, stroke, left ventricular ejection fraction or right ventricle dysfunction.CONCLUSIONSDel Nido cardioplegia has been used in complex cardiac surgery requiring prolonged cross-clamp. Re-dosing can be performed with either FD or dilute del Nido solution with no statistical difference in outcomes.     

Aggressive Surgical Approach for Patients with T4 Gastric Carcinoma: Promise or Myth?

Background

Surgical outcomes of multiorgan resection (MOR) for T4 gastric carcinoma reported in the literature are widely variable. We herein report a large surgical series of T4 gastric carcinoma.

Methods

One hundred seventy-nine patients with cT4 gastric carcinoma were recruited onto the study. Patient characteristics, surgical strategy and related complications, long-term survival, and prognostic factors of T4 gastric carcinoma were analyzed.

Results

Of 179 cT4 gastric carcinoma, there were 57 cT4 (pT3) with MOR, 91 pT4 with MOR, and 31 cT4 without MOR. pT4 with MOR were more likely to be associated with nodal metastasis, cellular dedifferentiation, and lymphoperineural infiltration compared to those of pT0–3 (P < 0.01 for all). For 91 pT4 with MOR, their surgical mortality and morbidity rates were 4.4 and 28.6%, respectively; their 1-, 3-, and 5-year overall survival rates were 55.2, 22.4, and 12.2%, respectively. The long-term survival of cT4 (pT3) with MOR was superior to pT4 with MOR (P = 0.006) and cT4 without MOR (P = 0.004). There was a striking difference between pT4 with MOR, R0 and pT4 with MOR, and R1 or R2 (P = 0.007). By means of multivariate analysis, lymph node status, liver invasion, and positive surgical margin were independent prognostic factors.

Conclusions

Aggressive surgical management of pT4 gastric carcinoma should be limited to patients without adverse prognostic factors such as advanced nodal involvement and pancreatic invasion.     

The Acute Surgical Unit Model Verses the Traditional “On Call” Model: A Systematic Review and Meta-Analysis

Background

The acute surgical unit (ASU) is a novel model for the provision of emergency general surgery care. The ASU model was initially developed in New South Wales hospitals during 2005 and 2006. Several studies have analysed the effects on patient outcomes and timeliness of care for nontrauma patients presenting with acute general surgical conditions. The purpose of this study was to perform a meta-analysis to determine the efficacy of the ASU model compared with the traditional on-call model for specific conditions.

Methods

A systematic search was conducted using MEDLINE, PubMed, EMBASE, Current Contents Connect, Cochrane library, Google Scholar, Science Direct, and Web of Science. Original data were extracted from each study and used to calculate a pooled odd ratio (OR) and 95 % confidence interval (CI).

Results

The search identified 18 studies; appendectomy (n = 9), acute cholecystitis (n = 7), and small-bowel obstruction (SBO) (n = 2). In the appendectomy cohort, the proportion of appendicular perforation were similar in pre-ASU and ASU period (OR 1.02, 95 % CI 0.77–1.37, p = 0.13). The incidence of complications in the appendectomy cohort was significantly lower in the ASU group; 14.5 % pre-ASU and 10.9 % post-ASU (OR 1.649, 95 % CI 0.732–3.714, p = 0.009). The negative appendectomy rate was similar for the pre- and post-ASU groups (OR 1.07, 95 % CI 0.88–1.31, p = 0.83). Likewise the conversion rate to open surgery and total hospital stay were similar between the two groups. The proportion of night time operations reduced significantly in the ASU period (OR 1.9, 95 % CI 1.32–2.74, p = 0.001). In the acute cholecystitis cohort, the conversion rate to open surgery was significantly higher in the pre-ASU group (15.1 %) compared with the post-ASU group (7.5 %) (OR 1.879, 95 % CI 1.072–3.293, p = 0.04) The incidence of complications was higher in the pre-ASU (14 %) compared with the post-ASU (6.8 %) group (OR 2.231, 95 % CI 1.372–3.236, p = 0.03). The mean hospital stay was significantly lower in the ASU period (5.3 vs. 3.7 days, p = 0.0063). There was insufficient data available to analyse outcomes for SBO.

Conclusions

The ASU model provides a safe surgical environment for patients and is associated with a reduced complication rate for appendectomy and laparoscopic cholecystectomy for acute cholecystitis. There is a reduced conversion rate and a shorter length of stay for patients with acute cholecystitis. Overall, the ASU model has translated to better outcomes for patients presenting with acute general surgical conditions.     

Entomopthoromycosis--report of four cases

Entomopthoromycosis is a rare subcutaneous infection and manifests in two clinically distinct forms. Subcutaneous zygomycosis which manifests as a painless nodule on the trunk or the extremities and rhinofacial zygomycosis which is a locally progressive infection of the nasal cavity, paranasal sinuses and soft tissues of the face. Neither of these two forms occur in patients with underlying disease or defective immunity. Here we report four cases of entomopthoromycosis.