\documentclass[10pt]{article}

\usepackage{fullpage}
\usepackage{setspace}
\usepackage{parskip}
\usepackage{titlesec}
\usepackage[section]{placeins}
\usepackage{xcolor}
\usepackage{breakcites}
\usepackage{lineno}
\usepackage{hyphenat}





\PassOptionsToPackage{hyphens}{url}
\usepackage[colorlinks = true,
            linkcolor = blue,
            urlcolor  = blue,
            citecolor = blue,
            anchorcolor = blue]{hyperref}
\usepackage{etoolbox}
\makeatletter
\patchcmd\@combinedblfloats{\box\@outputbox}{\unvbox\@outputbox}{}{%
  \errmessage{\noexpand\@combinedblfloats could not be patched}%
}%
\makeatother


\usepackage{natbib}




\renewenvironment{abstract}
  {{\bfseries\noindent{\abstractname}\par\nobreak}\footnotesize}
  {\bigskip}

\titlespacing{\section}{0pt}{*3}{*1}
\titlespacing{\subsection}{0pt}{*2}{*0.5}
\titlespacing{\subsubsection}{0pt}{*1.5}{0pt}


\usepackage{authblk}


\usepackage{graphicx}
\usepackage[space]{grffile}
\usepackage{latexsym}
\usepackage{textcomp}
\usepackage{longtable}
\usepackage{tabulary}
\usepackage{booktabs,array,multirow}
\usepackage{amsfonts,amsmath,amssymb}
\providecommand\citet{\cite}
\providecommand\citep{\cite}
\providecommand\citealt{\cite}
% You can conditionalize code for latexml or normal latex using this.
\newif\iflatexml\latexmlfalse
\providecommand{\tightlist}{\setlength{\itemsep}{0pt}\setlength{\parskip}{0pt}}%

\AtBeginDocument{\DeclareGraphicsExtensions{.pdf,.PDF,.eps,.EPS,.png,.PNG,.tif,.TIF,.jpg,.JPG,.jpeg,.JPEG}}

\usepackage[utf8]{inputenc}
\usepackage[english]{babel}



\usepackage{float}








\begin{document}

\title{Improving the management of cervical chyle leak following neck
dissection: A case series of management algorithm; 10 years clinical
experience with Video Assisted Thoracoscopy and Thoracic Duct Ligation}



\author[1]{Ali Al-lami}%
\author[2]{Eamon Shamil}%
\author[3]{Iain Nixon}%
\author[4]{Jean-Pierre Jeannon}%
\author[5]{Andrea Bille}%
\author[5]{Karen Harrison-Phipps}%
\author[4]{Ricard Simo}%
\affil[1]{East Kent Hospitals University NHS Foundation Trust}%
\affil[2]{Guy's and St Thomas' NHS Foundation Trust}%
\affil[3]{NHS Lothian}%
\affil[4]{Guy's and St. Thomas NHS Foundation Trust}%
\affil[5]{Guy's and Saint Thomas' NHS Foundation Trust}%


\vspace{-1em}



  
  \date{May 04, 2024}


\begingroup
\let\center\flushleft
\let\endcenter\endflushleft
\maketitle
\endgroup





\selectlanguage{english}
\begin{abstract}
Key points instead of abstract as per author guidelines: * Chyle leaks
(CLs) following neck dissection for metastatic head and neck malignancy
are infrequent but represent a serious complication, with an incidence
of 1-2.5\%. * CL is associated with significant morbidity including
metabolic imbalance, immunosuppression, dehydration, poor wound healing
and prolonged length of hospital stay. * A protocolised approach to the
management of CL post neck dissections is highlighted for expedient
patient management. * Thoracic duct (TD) ligation using video-assisted
thoracoscopic surgery (VATS) is an effective method of treating moderate
(500-1000ml/24 hours) to high-volume CL (\textgreater{}1000ml/24 hours)
not responding to medical therapy. * VATS TD ligation is a safe
procedure to treat CL. It has a low morbidity compared to other surgical
techniques (neck re-exploration or open thoracotomy).%
\end{abstract}%



\sloppy


Key points:

\begin{itemize}
\tightlist
\item
  Chyle leaks (CLs) following neck dissection for metastatic head and
  neck malignancy are infrequent but represent a serious complication,
  with an incidence of 1-2.5\%.
\item
  CL is associated with significant morbidity including metabolic
  imbalance, immunosuppression, dehydration, poor wound healing and
  prolonged length of hospital stay.
\item
  A protocolised approach to the management of CL post neck dissections
  is highlighted for expedient patient management.
\item
  Thoracic duct (TD) ligation using video-assisted thoracoscopic surgery
  (VATS) is an effective method of treating moderate (500-1000ml/24
  hours) to high-volume CL (\textgreater{}1000ml/24 hours) not
  responding to medical therapy.
\item
  VATS TD ligation is a safe procedure to treat CL. It has a low
  morbidity compared to other surgical techniques (neck re-exploration
  or open thoracotomy).
\end{itemize}

\textbf{Introduction}

Chyle leaks (CL) following neck dissection are an infrequent but can
represent a serious complication. An incidence of 1-2.5\% is reported in
patients undergoing neck dissections and is associated with thoracic
duct (TD) injury, particularly in the left side of the neck at the
terminal portion of the duct\textsuperscript{1}. The incidence rises
with metastatic lymphadenopathy in level 4 of the neck (most commonly
seen in thyroid and hypopharyngeal malignancy), bilateral neck
dissection or salvage surgery\textsuperscript{2}.

CL noted intra-operatively during neck dissection should be repaired
promptly. Recognition that diathermy and bipolar haemostasis is not
effective on dilated lymphatics due to lack of the haemoglobin protein
is mandated. Intra-operative techniques include the use of
non-absorbable suture, metallic ligaclips and fibrin sealant
utilisation. Fat-free diet is recommended to commence prophylactically
post-operatively to limit the pressure within the ligated TD in the hope
that this minimises CL post-operatively\textsuperscript{3}.

Post-operative CL noted by the presence of milky coloured fluid in the
drain should be promptly managed in a multi-disciplinary approach
involving dieticians, head and neck surgeons and thoracic surgeons.
Whilst awaiting biochemical confirmation with analysis of the drained
fluid by assessing the presence of elevated lymphocyte count,
triglycerides over 110mg/dl and chylomicron of more than
4\%\textsuperscript{4}, medical management is usually
commenced\textsuperscript{7}.

Currently there is no standardised treatment for the management of
CL\textsuperscript{5}. In 2011, we published a departmental instituted
guidelines on the management of CL based on best evidence available
(Figure 1) \textsuperscript{3}. Its aim was early identification,
risk-stratification and management of postoperative CL in order to
minimise morbidity. If surgical intervention is warranted, we advocated
Video Assisted Thoracic Surgery (VATS) procedure due to approaching the
TD in a non-operated field and thus in theory should be less morbid than
neck re-exploration.

At our institution, all CL are initially managed medically with a trial
of low-fat diet either via the oral intake route, naso-gastic feeding or
total parenteral nutrition, orlistat and octreotide. Low volume leaks
(\textless{}500ml/24h) are managed medically for 7-10 days. Moderate
volume leaks (500-1000ml/24h) are managed medically for 5-7 days. High
volume CL (\textgreater{}1000 ml/24h) are planned for early surgical
intervention whilst concurrently medical management is commenced.
Surgical intervention in the form of Video-Assisted Thoracoscopy Surgery
(VATS) thoracic duct (TD) ligation is pursued if the CL remain
unresolved despite medical management in low and moderate CL and where
the risk of medical complications such as infection and wound breakdown
is high.

The aim of this quality improvement study is to present the outcomes and
effectiveness of our management approach of CLs following the
implementation of the departmental standard operational protocol.

\textbf{Method}

The revised Standards for Quality Improvement Reporting Excellence
(SQUIRE 2.0) reporting methodology was adopted. A retrospective case
series review was conducted of all patients who developed clinically \&
biochemically confirmed CL following neck dissection for malignant head
and neck and thyroid disease between 2010 and 2019 at a tertiary head
and neck unit. Patients were managed as per the aforementioned unit
guidelines. In the multi-disciplinary management of patients, dietary
modifications were managed by dieticians and the VATS TD ligation
procedure were performed by the thoracic surgeons.

Medical management consisted of fat-free diet, orlistat and octreotide.
Surgical management via TD ligations by VATS procedure was carried out
when indicated.

During the VATS TD ligation, detection of the TD is achieved by using a
right-sided lateral approach to the thorax. The TD is subsequently
occluded by mass ligation of the tissue superior to the
supra-diaphragmatic hiatus, which lies between the aorta and the azygos
vein (figure 2).

Cessation of CL was defined as the termination of chyle like fluid from
the neck or the neck drain with biochemical confirmation.

\textbf{Results}

Eight patients developed CL post neck surgery (on average 3-5 neck
dissections are performed in our unit \textasciitilde{}1.6\% of the
estimated number of lateral neck dissections). Patients developed CL
between 1 and 7 days post neck surgery. One patient had an
intra-operative CL noted which was addressed at the time of neck
dissection but had chyle in the drain on day 1 post-operatively. There
were 5 males and 3 females. Median age was 35 (range 24-75 years) (Table
1). All patients had left neck dissections with 7 being bilateral. 5
patients had total thyroidectomies, two had total laryngectomies and one
patient had partial glossectomy. All 8 patients had left sided level 4
neck lymph node dissections.

One patient had a low volume CL with 200mls/ 24 hours managed medically
with fat free diet, orlistat and octreotide for 22 days on outpatient
basis as the patient declined surgical intervention and the CL
eventually resolved. One patient had moderate volume CL and was managed
medically for 7 days and due to persistence of CL then underwent VATS TD
ligation. Six patients developed high volume CL from the outset and were
managed both medically and surgically with fat free diet, orlistat and
octreotide and then had TD ligation by VATS (date range 2- 9 days after
onset of CL). CL resolved within 24 hours of ligation in all patients.
There were no VATS TD ligation related complications. Length of
inpatient stay ranged from 3 to 35 days, and were dependent on non-chyle
leak related factors. Table 2 summarises the volume stratification of CL
and their management.

\textbf{Discussion}

Management of CL is challenging, however, early stratification by the
volume of CL can aid effective management. Postoperative medical
management measures, including fat-free diet, correction of metabolic
imbalances, somatostatin analogues (octreotide)\textsuperscript{5},
lipase inhibitors (Orlistat)\textsuperscript{6} and TPN (Total
parenteral nutrition) are often employed, however, if these are
ineffective, surgical interventions would be necessary. Lymphangiography
with sclerotherapy in the management of CL has also been reported in the
literature\textsuperscript{7}. The key findings from this quality
improvement project is that low and medium-volume leaks are managed
medically with a defined timeframe to consideration of surgical
intervention in the form of VATS TD ligation if the CL is not resolving.
High volume CL are commenced on medical management initially whilst
early arrangements for a surgical intervention is encouraged. The data
from this study indicates that VATS TD ligation is a safe and effective
procedure with all CL resolved by day 1 post VATS TD ligation.

\textbf{Comparison with other studies}

Failed medical therapy or surgical re-exploration of the neck may fail
and further delay definitive treatment as postoperative inflammation
makes the TD more difficult to identify\textsuperscript{3}. Delayed
therapy increases the likelihood of complications. Previously published
studies corroborate our results in that VATS ligation of the TD
expediently halts the high drain output, and avoids the surgical
morbidity associated with open thoracotomy\textsuperscript{8}.

VATS TD ligation is a low morbidity procedure and thus patients could
potentially be discharged earlier\textsuperscript{9}. The shorter
duration of CL means they are less likely to develop metabolic,
nutritional and immune complications. The resolution of CL after VATS TD
ligation promotes an enhanced recovery of head and neck patients.

VATS ligation of the TD is an effective surgical approach of treating CL
demonstrated by the 100\% success rate of this case series. It has been
shown to have high success and minimal complications rates compared to
open thoracotomy\textsuperscript{8}. Ilczyszyn et
al\textsuperscript{9}reviewed a series of case reports and concluded
that thoracoscopic ligation is effective at stemming intractable chyle
fistulas, with no added morbidity. In addition, it avoids the
significant risk of morbidity associated with major thoracic access thus
decreasing hospital stay\textsuperscript{10}.

This study adds to the body of evidence in the management of CL by
providing guidance on the timeframe for medical management and when to
consider surgical intervention. In addition, to our knowledge, it is the
largest case series reporting on outcomes of VATS TD ligation procedure
for CL management after neck dissection. Akin to the systematic review
of CL medical management\textsuperscript{5}, a systematic review and
meta-analysis of the surgical management of CL would add valuable
evidence to the management of this rare complication of neck dissection.

\textbf{Limitations of this study}

Due to the rarity of CL as a complication of neck surgery, even a
10-year retrospective case series in a major UK tertiary referral centre
yielded a low number of patients, which limits the power of the study.
Furthermore, it is a non-controlled study. Both of these limitations are
due to the rarity of CL post neck surgery. Nonetheless, this study
highlights and assesses the effectiveness of a timeframe of the medical
and surgical management of CL that head and neck teams can incorporate
into their clinical practice.

\textbf{Conclusions}

CL is a rare but potentially troublesome complication of head and neck
oncological surgery involving neck dissections. Although medical
measures are employed, non-resolving low and medium volume leaks as well
as high-volume leaks may require surgical intervention. An agreed
management protocol should be encouraged to manage patients with CL.
Early VATS ligation of the TD provides a safe and an effective method of
treating high-volume (\textgreater{}1000ml) CL refractory to medical
interventions.

\textbf{References}

1. De Gier HH, Balm AJ, Bruning PF, Gregor RT, Hilgers FJ. Systematic
approach to the treatment of chylous leakage after neck dissection. Head
Neck. 1996; 18: 347--51.

2. Lee YS, Nam KH, Chung WY, Chang HS, Park CS. Postoperative
complications of thyroid cancer in a single center experience. J Korean
Med Sci. 2010; 25: 541--5.

3. Joshi A, Nixon IJ, Harrison-Phipps K, Jeannon JP, Oakley R, Simo R.
Management of cervical chyle leaks. J ENT Masterclass. 2011; 4(1):
90-94.

4. Gregor RT. Management of chyle fistulization in association with neck
dissection. Otolaryngol Head Neck Surg. 2000; 122: 434--9.

5. Molena E, King E, Davies-Husband C. Octreotide versus oral dietary
modification for the treatment of chylous fistula following neck
dissection: a systematic review and meta-analysis. Clinical
Otolaryngoogy. 2021;46(3):474-484.

6. Belloso A, Saravanan K, De Carpentier J. The community management of
chylous fistula using a pancreatic lipase inhibitor (orlistat).
Laryngoscope. 2006;116: 1934--5.

7. Mullins JK, Pierorazio PM, Hyams ES, Mitchell SE, Allf ME.
Lymphangiography with sclerotherapy: a novel therapy for refractory
chylous ascites. Can J Urol. 2012;19(3): 6250-4.

8. Abdel-Galil K, Milton R, McCaul J. High output chyle leak after neck
surgery: the role of video-assisted thoracoscopic surgery. Br J Oral
Maxillofac Surg. 2009;47\textbf{:} 478--80.

9. Ilczyszyn A, Ridha H, Durrani AJ. Management of chyle leak post neck
dissection: a case report and literature review. J Plast Reconstr
Aesthet Surg. 2011;64\textbf{:} e223-30.

10. Wurnig PN, Hollaus PH, Ohtsuka T, Flege JB, Wolf RK. Thoracoscopic
direct clipping of the thoracic duct for chylopericardium and
chylothorax. Ann Thorac Surg. 2000;70\textbf{:} 1662--5.

\textbf{Hosted file}

\verb`Figure 1 - Clin otol .docx`  available at \url{https://authorea.com/users/477088/articles/565829-improving-the-management-of-cervical-chyle-leak-following-neck-dissection-a-case-series-of-management-algorithm-10-years-clinical-experience-with-video-assisted-thoracoscopy-and-thoracic-duct-ligation}

\textbf{Hosted file}

\verb`Figure 2 clin otol.docx`  available at \url{https://authorea.com/users/477088/articles/565829-improving-the-management-of-cervical-chyle-leak-following-neck-dissection-a-case-series-of-management-algorithm-10-years-clinical-experience-with-video-assisted-thoracoscopy-and-thoracic-duct-ligation}

\textbf{Hosted file}

\verb`Table 1 - Clin otol.docx`  available at \url{https://authorea.com/users/477088/articles/565829-improving-the-management-of-cervical-chyle-leak-following-neck-dissection-a-case-series-of-management-algorithm-10-years-clinical-experience-with-video-assisted-thoracoscopy-and-thoracic-duct-ligation}

\textbf{Hosted file}

\verb`Table 2 - Clin otol.docx`  available at \url{https://authorea.com/users/477088/articles/565829-improving-the-management-of-cervical-chyle-leak-following-neck-dissection-a-case-series-of-management-algorithm-10-years-clinical-experience-with-video-assisted-thoracoscopy-and-thoracic-duct-ligation}

\selectlanguage{english}
\FloatBarrier
\end{document}

