<?xml version="1.0" encoding="us-ascii"?><InstanceReport xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"><Version>2.4.0.8</Version><ReportLongName>107 - Disclosure - Supplemental Cash Flow Information</ReportLongName><DisplayLabelColumn>true</DisplayLabelColumn><ShowElementNames>false</ShowElementNames><RoundingOption /><HasEmbeddedReports>false</HasEmbeddedReports><Columns><Column FlagID="0"><Id>1</Id><IsAbstractGroupTitle>false</IsAbstractGroupTitle><LabelSeparator>

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</LabelSeparator><Level>1</Level><ElementName>us-gaap_SupplementalCashFlowInformationAbstract</ElementName><ElementPrefix>us-gaap_</ElementPrefix><IsBaseElement>true</IsBaseElement><BalanceType>na</BalanceType><PeriodType>duration</PeriodType><IsReportTitle>false</IsReportTitle><IsSegmentTitle>false</IsSegmentTitle><IsCalendarTitle>false</IsCalendarTitle><IsEquityPrevioslyReportedAsRow>false</IsEquityPrevioslyReportedAsRow><IsEquityAdjustmentRow>false</IsEquityAdjustmentRow><IsBeginningBalance>false</IsBeginningBalance><IsEndingBalance>false</IsEndingBalance><IsReverseSign>false</IsReverseSign><FootnoteIndexer /><Cells><Cell FlagID="0" ContextID="" UnitID=""><Id>1</Id><IsNumeric>false</IsNumeric><IsRatio>false</IsRatio><DisplayZeroAsNone>false</DisplayZeroAsNone><NumericAmount>0</NumericAmount><RoundedNumericAmount>0</RoundedNumericAmount><NonNumbericText /><FootnoteIndexer /><CurrencyCode /><CurrencySymbol /><IsIndependantCurrency>false</IsIndependantCurrency><ShowCurrencySymbol>false</ShowCurrencySymbol><DisplayDateInUSFormat>false</DisplayDateInUSFormat></Cell></Cells><ElementDataType>xbrli:stringItemType</ElementDataType><SimpleDataType>string</SimpleDataType><IsTotalLabel>false</IsTotalLabel><UnitID>0</UnitID><Label>Supplemental Cash Flow Information [Abstract]</Label></Row><Row FlagID="0"><Id>2</Id><IsAbstractGroupTitle>false</IsAbstractGroupTitle><LabelSeparator>

</LabelSeparator><Level>2</Level><ElementName>us-gaap_CashFlowSupplementalDisclosuresTextBlock</ElementName><ElementPrefix>us-gaap_</ElementPrefix><IsBaseElement>true</IsBaseElement><BalanceType>na</BalanceType><PeriodType>duration</PeriodType><IsReportTitle>false</IsReportTitle><IsSegmentTitle>false</IsSegmentTitle><IsCalendarTitle>false</IsCalendarTitle><IsEquityPrevioslyReportedAsRow>false</IsEquityPrevioslyReportedAsRow><IsEquityAdjustmentRow>false</IsEquityAdjustmentRow><IsBeginningBalance>false</IsBeginningBalance><IsEndingBalance>false</IsEndingBalance><IsReverseSign>false</IsReverseSign><PreferredLabelRole>terseLabel</PreferredLabelRole><FootnoteIndexer /><Cells><Cell FlagID="0" ContextID="from-2013-01-01-to-2013-06-30.1153.0.0.0.0.0.0.0" UnitID=""><Id>1</Id><IsNumeric>false</IsNumeric><IsRatio>false</IsRatio><DisplayZeroAsNone>false</DisplayZeroAsNone><NumericAmount>0</NumericAmount><RoundedNumericAmount>0</RoundedNumericAmount><NonNumbericText>&lt;!--DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd" --&gt;&lt;div&gt; &lt;div&gt;&lt;!--StartFragment--&gt; &lt;p style="FONT: 10pt Times New Roman, Times, Serif; MARGIN: 0pt 0px"&gt; &lt;strong&gt;7. Supplemental Cash Flow Information&lt;/strong&gt;&lt;/p&gt; &lt;p style="FONT: 10pt Times New Roman, Times, Serif; MARGIN: 0pt 0px"&gt; &amp;nbsp;&lt;/p&gt; &lt;p style="FONT: 10pt Times New Roman, Times, Serif; MARGIN: 0pt 0px; TEXT-INDENT: 0.5in"&gt; Supplemental cash flow information for the six months ended June 30, 2013 and 2012 is approximately as follows:&lt;/p&gt; &lt;p style="FONT: 10pt Times New Roman, Times, Serif; MARGIN: 0pt 0px; TEXT-INDENT: 0.5in"&gt; &amp;nbsp;&lt;/p&gt; &lt;table style="BORDER-COLLAPSE: collapse; FONT: 10pt Times New Roman, Times, Serif; MARGIN-LEFT: 0.5in; WIDTH: 85%" cellspacing="0" cellpadding="0"&gt; &lt;tr style="VERTICAL-ALIGN: bottom"&gt; &lt;td&gt;&amp;nbsp;&lt;/td&gt; &lt;td style="FONT-WEIGHT: bold; PADDING-BOTTOM: 1pt"&gt;&amp;nbsp;&lt;/td&gt; &lt;td style="BORDER-BOTTOM: black 1pt solid; FONT-WEIGHT: bold; TEXT-ALIGN: center" colspan="2"&gt;2013&lt;/td&gt; &lt;td style="FONT-WEIGHT: bold; PADDING-BOTTOM: 1pt"&gt;&amp;nbsp;&lt;/td&gt; &lt;td style="FONT-WEIGHT: bold; PADDING-BOTTOM: 1pt"&gt;&amp;nbsp;&lt;/td&gt; &lt;td style="BORDER-BOTTOM: black 1pt solid; FONT-WEIGHT: bold; TEXT-ALIGN: center" colspan="2"&gt;2012&lt;/td&gt; &lt;td style="FONT-WEIGHT: bold; PADDING-BOTTOM: 1pt"&gt;&amp;nbsp;&lt;/td&gt; &lt;/tr&gt; &lt;tr style="VERTICAL-ALIGN: bottom"&gt; &lt;td&gt;&amp;nbsp;&lt;/td&gt; &lt;td style="FONT-WEIGHT: bold"&gt;&amp;nbsp;&lt;/td&gt; &lt;td style="FONT-WEIGHT: bold; TEXT-ALIGN: center" colspan="2"&gt; &amp;nbsp;&lt;/td&gt; &lt;td style="FONT-WEIGHT: bold"&gt;&amp;nbsp;&lt;/td&gt; &lt;td style="FONT-WEIGHT: bold"&gt;&amp;nbsp;&lt;/td&gt; &lt;td style="FONT-WEIGHT: bold; TEXT-ALIGN: center" colspan="2"&gt; &amp;nbsp;&lt;/td&gt; &lt;td style="FONT-WEIGHT: bold"&gt;&amp;nbsp;&lt;/td&gt; &lt;/tr&gt; &lt;tr style="VERTICAL-ALIGN: bottom; BACKGROUND-COLOR: rgb(204,255,204)"&gt; &lt;td style="TEXT-ALIGN: left; WIDTH: 74%"&gt;Cash paid for interest&lt;/td&gt; &lt;td style="WIDTH: 1%"&gt;&amp;nbsp;&lt;/td&gt; &lt;td style="TEXT-ALIGN: left; WIDTH: 1%"&gt;$&lt;/td&gt; &lt;td style="TEXT-ALIGN: right; WIDTH: 10%"&gt;96,000&lt;/td&gt; &lt;td style="TEXT-ALIGN: left; WIDTH: 1%"&gt;&amp;nbsp;&lt;/td&gt; &lt;td style="WIDTH: 1%"&gt;&amp;nbsp;&lt;/td&gt; &lt;td style="TEXT-ALIGN: left; WIDTH: 1%"&gt;$&lt;/td&gt; &lt;td style="TEXT-ALIGN: right; WIDTH: 10%"&gt;126,000&lt;/td&gt; &lt;td style="TEXT-ALIGN: left; WIDTH: 1%"&gt;&amp;nbsp;&lt;/td&gt; &lt;/tr&gt; &lt;tr style="VERTICAL-ALIGN: bottom; BACKGROUND-COLOR: white"&gt; &lt;td style="TEXT-ALIGN: left"&gt;&amp;nbsp;&lt;/td&gt; &lt;td&gt;&amp;nbsp;&lt;/td&gt; &lt;td style="TEXT-ALIGN: left"&gt;&amp;nbsp;&lt;/td&gt; &lt;td style="TEXT-ALIGN: right"&gt;&amp;nbsp;&lt;/td&gt; &lt;td style="TEXT-ALIGN: left"&gt;&amp;nbsp;&lt;/td&gt; &lt;td&gt;&amp;nbsp;&lt;/td&gt; &lt;td style="TEXT-ALIGN: left"&gt;&amp;nbsp;&lt;/td&gt; &lt;td style="TEXT-ALIGN: right"&gt;&amp;nbsp;&lt;/td&gt; &lt;td style="TEXT-ALIGN: left"&gt;&amp;nbsp;&lt;/td&gt; &lt;/tr&gt; &lt;tr style="VERTICAL-ALIGN: bottom; BACKGROUND-COLOR: rgb(204,255,204)"&gt; &lt;td style="TEXT-ALIGN: left; PADDING-LEFT: 0.1in; TEXT-INDENT: -0.1in"&gt; Non-cash investing and financing activities:&lt;/td&gt; &lt;td&gt;&amp;nbsp;&lt;/td&gt; &lt;td style="TEXT-ALIGN: left"&gt;&amp;nbsp;&lt;/td&gt; &lt;td style="TEXT-ALIGN: right"&gt;&amp;nbsp;&lt;/td&gt; &lt;td style="TEXT-ALIGN: left"&gt;&amp;nbsp;&lt;/td&gt; &lt;td&gt;&amp;nbsp;&lt;/td&gt; &lt;td style="TEXT-ALIGN: left"&gt;&amp;nbsp;&lt;/td&gt; &lt;td style="TEXT-ALIGN: right"&gt;&amp;nbsp;&lt;/td&gt; &lt;td style="TEXT-ALIGN: left"&gt;&amp;nbsp;&lt;/td&gt; &lt;/tr&gt; &lt;tr style="VERTICAL-ALIGN: bottom; BACKGROUND-COLOR: white"&gt; &lt;td style="TEXT-ALIGN: left; PADDING-LEFT: 16.2pt; TEXT-INDENT: -0.1in"&gt; Beneficial conversion feature issued with convertible debt&lt;/td&gt; &lt;td&gt;&amp;nbsp;&lt;/td&gt; &lt;td style="TEXT-ALIGN: left"&gt;$&lt;/td&gt; &lt;td style="TEXT-ALIGN: right"&gt;-&lt;/td&gt; &lt;td style="TEXT-ALIGN: left"&gt;&amp;nbsp;&lt;/td&gt; &lt;td&gt;&amp;nbsp;&lt;/td&gt; &lt;td style="TEXT-ALIGN: left"&gt;$&lt;/td&gt; &lt;td style="TEXT-ALIGN: right"&gt;216,000&lt;/td&gt; &lt;td style="TEXT-ALIGN: left"&gt;&amp;nbsp;&lt;/td&gt; &lt;/tr&gt; &lt;tr style="VERTICAL-ALIGN: bottom; BACKGROUND-COLOR: rgb(204,255,204)"&gt; &lt;td style="TEXT-ALIGN: left; PADDING-LEFT: 16.2pt; TEXT-INDENT: -0.1in"&gt; Conversion of debt and accrued interest to equity&lt;/td&gt; &lt;td&gt;&amp;nbsp;&lt;/td&gt; &lt;td style="TEXT-ALIGN: left"&gt;$&lt;/td&gt; &lt;td style="TEXT-ALIGN: right"&gt;-&lt;/td&gt; &lt;td style="TEXT-ALIGN: left"&gt;&amp;nbsp;&lt;/td&gt; &lt;td&gt;&amp;nbsp;&lt;/td&gt; &lt;td style="TEXT-ALIGN: left"&gt;$&lt;/td&gt; &lt;td style="TEXT-ALIGN: right"&gt;580,000&lt;/td&gt; &lt;td style="TEXT-ALIGN: left"&gt;&amp;nbsp;&lt;/td&gt; &lt;/tr&gt; &lt;tr style="VERTICAL-ALIGN: bottom; BACKGROUND-COLOR: white"&gt; &lt;td style="TEXT-ALIGN: left; PADDING-LEFT: 16.2pt; TEXT-INDENT: -0.1in"&gt; Warrant issued for prepaid consulting services&lt;/td&gt; &lt;td&gt;&amp;nbsp;&lt;/td&gt; &lt;td style="TEXT-ALIGN: left"&gt;$&lt;/td&gt; &lt;td style="TEXT-ALIGN: right"&gt;-&lt;/td&gt; &lt;td style="TEXT-ALIGN: left"&gt;&amp;nbsp;&lt;/td&gt; &lt;td&gt;&amp;nbsp;&lt;/td&gt; &lt;td style="TEXT-ALIGN: left"&gt;$&lt;/td&gt; &lt;td style="TEXT-ALIGN: right"&gt;248,000&lt;/td&gt; &lt;td style="TEXT-ALIGN: left"&gt;&amp;nbsp;&lt;/td&gt; &lt;/tr&gt; &lt;tr style="VERTICAL-ALIGN: bottom; BACKGROUND-COLOR: rgb(204,255,204)"&gt; &lt;td style="TEXT-ALIGN: left; PADDING-LEFT: 16.2pt; TEXT-INDENT: -0.1in"&gt; Gain (loss)from change in fair value of interest rate swap derivative&lt;/td&gt; &lt;td&gt;&amp;nbsp;&lt;/td&gt; &lt;td style="TEXT-ALIGN: left"&gt;$&lt;/td&gt; &lt;td style="TEXT-ALIGN: right"&gt;76,000&lt;/td&gt; &lt;td style="TEXT-ALIGN: left"&gt;&amp;nbsp;&lt;/td&gt; &lt;td&gt;&amp;nbsp;&lt;/td&gt; &lt;td style="TEXT-ALIGN: left"&gt;$&lt;/td&gt; &lt;td style="TEXT-ALIGN: right"&gt;(22,000&lt;/td&gt; &lt;td style="TEXT-ALIGN: left"&gt;)&lt;/td&gt; &lt;/tr&gt; &lt;tr style="VERTICAL-ALIGN: bottom; BACKGROUND-COLOR: white"&gt; &lt;td style="TEXT-ALIGN: left; PADDING-LEFT: 16.2pt; TEXT-INDENT: -0.1in"&gt; Warrants issued with debt&lt;/td&gt; &lt;td&gt;&amp;nbsp;&lt;/td&gt; &lt;td style="TEXT-ALIGN: left"&gt;$&lt;/td&gt; &lt;td style="TEXT-ALIGN: right"&gt;69,000&lt;/td&gt; &lt;td style="TEXT-ALIGN: left"&gt;&amp;nbsp;&lt;/td&gt; &lt;td&gt;&amp;nbsp;&lt;/td&gt; &lt;td style="TEXT-ALIGN: left"&gt;$&lt;/td&gt; &lt;td style="TEXT-ALIGN: right"&gt;-&lt;/td&gt; &lt;td style="TEXT-ALIGN: left"&gt;&amp;nbsp;&lt;/td&gt; &lt;/tr&gt; &lt;tr style="VERTICAL-ALIGN: bottom; BACKGROUND-COLOR: rgb(204,255,204)"&gt; &lt;td style="TEXT-ALIGN: left; PADDING-LEFT: 16.2pt; TEXT-INDENT: -0.1in"&gt; Accounts payable converted to debt&lt;/td&gt; &lt;td&gt;&amp;nbsp;&lt;/td&gt; &lt;td style="TEXT-ALIGN: left"&gt;$&lt;/td&gt; &lt;td style="TEXT-ALIGN: right"&gt;153,000&lt;/td&gt; &lt;td style="TEXT-ALIGN: left"&gt;&amp;nbsp;&lt;/td&gt; &lt;td&gt;&amp;nbsp;&lt;/td&gt; &lt;td style="TEXT-ALIGN: left"&gt;$&lt;/td&gt; &lt;td style="TEXT-ALIGN: right"&gt;-&lt;/td&gt; &lt;td style="TEXT-ALIGN: left"&gt;&amp;nbsp;&lt;/td&gt; &lt;/tr&gt; &lt;tr style="VERTICAL-ALIGN: bottom; BACKGROUND-COLOR: white"&gt; &lt;td style="TEXT-ALIGN: left; PADDING-LEFT: 16.2pt; TEXT-INDENT: -0.1in"&gt; Financing of equipment purchase&lt;/td&gt; &lt;td&gt;&amp;nbsp;&lt;/td&gt; &lt;td style="TEXT-ALIGN: left"&gt;$&lt;/td&gt; &lt;td style="TEXT-ALIGN: right"&gt;697,000&lt;/td&gt; &lt;td style="TEXT-ALIGN: left"&gt;&amp;nbsp;&lt;/td&gt; &lt;td&gt;&amp;nbsp;&lt;/td&gt; &lt;td style="TEXT-ALIGN: left"&gt;$&lt;/td&gt; &lt;td style="TEXT-ALIGN: right"&gt;-&lt;/td&gt; &lt;td style="TEXT-ALIGN: left"&gt;&amp;nbsp;&lt;/td&gt; &lt;/tr&gt; &lt;tr style="VERTICAL-ALIGN: bottom; BACKGROUND-COLOR: rgb(204,255,204)"&gt; &lt;td style="PADDING-LEFT: 16.2pt; TEXT-INDENT: -0.1in"&gt;Intrinsic value of beneficial conversion feature at Reaquisition&lt;/td&gt; &lt;td&gt;&amp;nbsp;&lt;/td&gt; &lt;td style="TEXT-ALIGN: left"&gt;$&lt;/td&gt; &lt;td style="TEXT-ALIGN: right"&gt;75,000&lt;/td&gt; &lt;td style="TEXT-ALIGN: left"&gt;&amp;nbsp;&lt;/td&gt; &lt;td&gt;&amp;nbsp;&lt;/td&gt; &lt;td style="TEXT-ALIGN: left"&gt;$&lt;/td&gt; &lt;td style="TEXT-ALIGN: right"&gt;-&lt;/td&gt; &lt;td style="TEXT-ALIGN: left"&gt;&amp;nbsp;&lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; &lt;p style="FONT: 10pt Times New Roman, Times, Serif; MARGIN: 0pt 0px"&gt; &lt;strong&gt;&amp;nbsp;&lt;/strong&gt;&lt;/p&gt; &lt;!--EndFragment--&gt;&lt;/div&gt; &lt;/div&gt;</NonNumbericText><FootnoteIndexer /><CurrencyCode /><CurrencySymbol /><IsIndependantCurrency>false</IsIndependantCurrency><ShowCurrencySymbol>false</ShowCurrencySymbol><DisplayDateInUSFormat>false</DisplayDateInUSFormat></Cell></Cells><ElementDataType>nonnum:textBlockItemType</ElementDataType><SimpleDataType>na</SimpleDataType><ElementDefenition>The entire disclosure for supplemental cash flow activities, including cash, noncash, and part noncash transactions, for the period. Noncash is defined as information about all investing and financing activities of an enterprise during a period that affect recognized assets or liabilities but that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.</ElementDefenition><ElementReferences>Reference 1: http://www.xbrl.org/2003/role/presentationRef

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